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Fish and fish waste-based fertilizers in organic farming – With status in Norway: A review
Abstract
This paper reviews relevant knowledge about the production and uses of fertilizers from fish and fish waste (FW) that may be applicable for certified organic farming, with a focus on crop and horticultural plants. Fish industries generate a substantial amount of FW. Depending on the level of processing or type of fish, 30–70% of the original fish is FW. Circular economy and organic farming concepts were used to evaluate the potential of production of fertilizers from captured fish. Fertilizers produced from captured fish promote the recycling of nutrients from the sea and back to terrestrial environments. Nutritional composition of FW is assessed to determine the potential to supply plant nutrients such as nitrogen, or a combination of nitrogen and phosphorous, or to enrich a compost. Methods used in processing of FW to produce fish- emulsion, fish hydrolysate/fish silage, fish-compost and digestate from anaerobic digestion/co-digestion are presented. Using information about commercially available fish-based fertilizers listed by the Organic Materials Review Institute (OMRI), we present a scenario for establishing fish/FW-based fertilizers industry and research in Europe. With Norway’s 9th position among top ten global capture producers and focus in Norway on developing organic farming, we brief how FW is currently utilized and regulated, and discuss its availability for possible production of FW-based organic fertilizers. The amount of FW available in Norway for production of fertilizers may facilitate the establishment of an industrial product that can replace the currently common use of dried poultry manure from conventional farming in organic farming.
... At present, such fertilizers and composts are bearing great significance for organic farming practice. Fish fertilizer contains well-balanced nutrients for growth of crops [140] (Table 5). ...
... Based on processing methods, several terms are used to mean fish fertilizer products such as hydrolyzed waste/fish hydrolysate, fish silage, fish solubles/fish emulsion, fish meal, fish powder, and fish soluble nutrients [140]. According to the type of material, the processing steps vary. ...
... Fish silage can be modified into fishbone meal, fish meal or fish powder through further drying and used as fertilizers, or to make compost which can be mixed with other materials [140]. Fishbone meal or fish meal can be incorporated in liquid and solid fertilizer products [145]. ...
From ancient times fish has always been considered as an important human food item. The purpose of this article is to introduce the perception that beside consumption, fish can also be used as a raw material for the industrial production of different products. In this article such 19 products have been described. Among them, the conventional fish products described herein include isinglass, pituitary gland, chitin, chitosan, pearl essence, fish skin leather, fish protein hydrolysates and concentrates, fish meal and scrap, fish oil, collagen, gelatin, glue, fish silage, pet food and wet feed from fish, fish fertilizer and compost. These products have important applications in aquaculture, agriculture, food, cosmetics and other industries. Different non-conventional hi-tech fish products has been reported such as novel antimicrobial proteins from skin mucus, enzymes, insulin, protamine, blood proteins, salcotonin, antifreeze proteins, hydroxyapatite, burn treatment bandage, albumins, fishbone calcium powder, biochar, biopolymer, bioplastics, fish industry derived rinse water recovery. These products have many significant applications in chemical, biomedical and pharmaceutical industries. Economical, logistic, environmental and technological considerations from fish waste valorization perspectives has also been presented to evaluate feasibility of industrial-scale production of these products.
... The term "fish waste" (FW) refers to the whole fish when it is damaged. It includes heads (9-12%), bones (9-15%), viscera (12-18%), muscle trimmings (15-20%), skin and fins (1-3%) and scales [160,161] (Figure 5). Traditionally, FW is used in animal feed and fertilizer or is discarded in landfills, causing environmental problems, damage to the marine ecosystem and the generation of unpleasant odors [162][163][164]. ...
... Fish parts that are considered waste[158,160,161][158,160,161]. ...
... Fish parts that are considered waste[158,160,161][158,160,161]. ...
Waste generated from the agro-food industry represents a concerning environmental, social and economic issue. The Food and Agriculture Organization of the United Nations defines food waste as all food that decreases in quantity or quality to the extent that it is thrown out by food service providers and consumers. The FAO reports that 17% of worldwide food production may be wasted. Food waste may include fresh products, food close to the expiration date discarded by retailers and food products from household kitchens and eating establishments. However, food waste offers different possibilities to extract functional ingredients from different sources, such as dairy, cereals, fruits, vegetables, fibers, oils, dye and bioactive compounds. The optimization of agro-food waste as an ingredient will help in the development and innovation of food products to generate functional food and beverages to prevent and treat several diseases in consumers.
... The use of Lactobacilli starter culture and the addition of fermentable carbohydrates produce stable fish silage. Fish improves carbon/nitrogen ratio to 20 or 30 for better composting outcome (Ahuja et al. 2020) new specific microorganisms may emerge after undergoing these processes, which will be discussed in the following sections. ...
... Moreover, it safeguards essential decomposer microorganisms and increasing crop yields by 15% to 25% (Kefalew and Lami 2021) to their buffering capabilities. This unique feature allows for higher organic loading rates, which, in turn, improves microbial communities and facilitates the biodegradation of complex materials such as volatile fatty acids (Xu et al. 2018, Ahuja et al. 2020). Moreover, co-digestion can address the deficiency of essential micronutrients in FW that are crucial for microbial health, such as Ni, Co, Mo, Fe, and Se, which are typically low in FW. ...
A growing world population means greater pressure on earth’s resources. Currently, 30% of food is wasted, which poses a significant risk to both humans and the environment. One way to offset the growth in food waste (FW) is through the process of microbial bioconversion, whereby FW is transformed into a range of nutrient-dense biofertilisers. This approach not only promotes a highly desirable circular economy, but it can also reduce the use of inorganic fertilisers, which adversely impact the environment through increased greenhouse gases, changes in soil and water characteristics, and loss of biodiversity. The bioconversion of FW to biofertiliser relies on the processes of aerobic (composting) and anaerobic digestion. Recently, alternative decomposition techniques included growing specific beneficial microbes, such as effective microorganisms, to speed up the breakdown process. Microorganisms can act as biostimulants and biodecomposers, possessing nutrient-fixing abilities and providing protection from biotic and abiotic stresses, thus enhancing plant growth and overall health. The potential uses of FW are complex and diverse, but research is actively done to effectively utilise this resource for biofertiliser applications.
... Due to inappropriate postharvest handling practices, marketing concerns, and problems with the cold supply chain, perishable goods are wasted at various stages during the height of the growing season (Gogo et al., 2017;Pohlmann et al., 2020). Fruits, fish, and vegetables that decay fast must be delivered to consumers fresh, which may have an impact on their price and the postharvest average of various product variates (Ahuja et al., 2020;Tepe & Taştekin, 2022). In the USA, perishable product losses at the farm level are estimated to range from an average of 2 to 23% depending on the type of the product (Singh et al., 2018). ...
... Fish producers occasionally grade low-quality fish that cannot be consumed fresh, but prefer to grade higher-quality fish that may have a higher average of greater flavour (Redlingshofer et al., 2017). Due to the lower quality standards set by processed fish over nutrient-rich consumption, farmers choose to sell all of their products at lower prices than the expectation (Ahuja et al., 2020). This lowers the average number of unacceptable fishes and reduces the quantity lost in comparison with fresh fish. ...
Postharvest and supply chain losses are the main global challenges. The security of future food demand requires certain availability of natural resources and useful application of limited means. This study is based on maximizing the productive use of baren fish farms to meet future food demand. In this work, the simulation optimisation model was used to determine the estimated findings. We developed the life cycle measurement technique to examine the percentage loss occurred during postharvest and supply chain process and the assessment of its economic, environmental and social influences. Results demonstrate the variate average change of postharvest loss and supply chain loss of a farmer, processors, trader, wholesalers and retailers are, respectively, 7.06%, 8.89%, 6.23%, 9.10% and 13.05% regarding sample fish-form as compared to same capacity healthy land fish-form with a productive supply chain operation. The total healthy mud of land and quality water consumed to produce this lost food accumulated 60 thousand hectares and 255 million cubic meters apart from other producing inputs. It is estimated cost $380 million annually 7.8 million tons of growth. The study reveals the significance of better prevention approaches of life cycle waste to reduce the environmental, economic and social impacts. Additionally, it helps to diminish the postharvest loss percentage to decrease the perishability of products throughout the supply chain of aquaculture field and the mechanisms that protect the products until these are sold out to consumers. In order to reduce postharvest losses, the study suggests that farmers be included as supplier actors and measured twice, first at the production stage and then at the supply chain stage. With the use of well-organized techniques, the farmer’s education is a key component in reducing postharvest losses of perishable goods and boosting aquaculture sectors. Therefore, sustainable economic growth requires from farmers to supplier and productive coordination in reducing environmental impacts. This could improve their learning, skills and practices towards sustainable growth achievement in perishable products for meaningful use of natural resources.
... Fish waste undergoes various utilisation methods, including its conversion into fishmeal or fertilisers, as well as its direct incorporation as raw material for aquaculture feed [16,17] Regarding human food applications, fish discards can also be valorised through surimi production [18]. For instance, surimi refers to deboned, minced, and washed fish meat, serving as a range of seafood's key ingredients [19]. ...
... Nominal catches by species in the Azores[13][14][15][16]. Cont. ...
In response to the exponential growth in world population, there has been a striking surge in the volume of discarded fish worldwide. This surge is particularly evident in the fish processing industry, where a substantial amount of waste is generated, posing significant environmental concerns. Consequently, the repurposing and utilisation of these waste materials have emerged as pivotal processes for the preservation of marine resources. By employing innovative strategies, valuable products can be extracted from these fish by-products, offering not only economic advantages but also contributing to mitigating environmental impacts. This comprehensive literature review focuses on exploring diverse avenues for using fish waste and extracting high-value materials such as bioactive peptides, collagen, and enzymes, elucidating their potential applications across various industries. The literature review also demonstrates the possibility of extracting various bio-compounds from highly diverse fish waste. It has been observed that there is a need for optimisation of extraction protocols, as the variation in extraction methods and respective conditions significantly affects the extraction yields of the products. Moreover, considering our specific interest in the fish species endemic to The Azores, a meticulous characterisation will be conducted, as there is limited knowledge about waste utilisation processes specific to this archipelago.
... Os resíduos de peixes podem ser processados para produzir fertilizantes para a agricultura orgânica, avançando no manejo sustentável, sendo aplicado mais frequentemente para fornecer N e P às culturas (AHUJA et al., 2020). A compostagem é uma forma tradicional de transformar resíduos em compostos orgânicos e pode ser realizada com resíduos de diferentes origens, a exemplo dos domésticos, das indústrias alimentícias e das atividades de pesca. ...
... A reciclagem, o processamento dos resíduos oriundos da atividade pesqueira e sua consequente valorização, dependem das condições locais e de estrutura industrial (AHUJA et al., 2020;KORKMAZ et al., 2021) sendo necessário analisar aspectos de investimento econômico para desenvolver uma gestão sustentável na Colônia Z3. ...
A pesca é uma atividade socioeconômica que, no Brasil, movimenta aproximadamente cinco bilhões de reais por ano e emprega 3,5 milhões de pessoas. Contudo, essa atividade e as atividades de transformação de produtos pesqueiros, apresentam potencial para a geração de impactos ambientais, tanto por sua extensividade, como pelo volume de resíduos gerados, os quais podem representar até 70% do peso dos animais capturados. Com base nessas características, esse trabalho teve como objetivo analisar a relação entre os resíduos pesqueiros e a sustentabilidade na Colônia de Pescadores Z3 e apresentar alternativas de transformação de resíduos de pescado em produtos com valor econômico. Para viabilizar essa proposta, foi realizada pesquisa qualitativa, descritiva, com auxílio das técnicas de pesquisas bibliográficas, entrevistas informais, entrevistas formais, visitas a localidade e observação direta. Como resultados, a análise das relações entre a atividade pesqueira e a sustentabilidade na Colônia de Pescadores Z3 permitiu concluir que essa atividade é importante para a promoção de empregos, renda e da cultura local. Entretanto, contribui para a geração de impactos negativos ao desenvolvimento local, principalmente, devido adestinação inadequada dos resíduos pesqueiros ao longo das décadas. Dessa forma, foram apresentadas cinco alternativas de transformação de resíduos da pesca em outros produtos, quais foram: fonte de proteína por hidrólise e farinha de peixe, silagem de pescados, compostagem de peixe, quitina e biocombustíveis, todos com potencial para gerar renda complementar à população que sobrevive da atividade pesqueira.
... Consequently, bioaccumulation and eutrophication, among other environmental causes, will impact other beings in the food web, such as humans and animals that feed on fish [24]. This impacts the world economy with the lower availability of fishing areas, directly affecting the fishing industry, food, and the environment [40]. In addition, humans are affected by consuming contaminated water or food and working directly with these products as farmers. ...
... For example, women who have had direct or indirect exposure to agrochemicals are more likely to develop breast cancer [45], and pregnant women have about a 30% chance of having children who develop childhood brain cancer [46] and a greater chance of having children with leukemia [47]. In addition, the fetus may present cardiac and neuronal problems and morphological alterations in the lower and upper limbs [40]. Men may have a 40% risk of developing prostate cancer compared to men who have not had contact with agrochemicals [48]. ...
Healthy eating habits are one of the requirements for the health of society. In particular, in natura foods are increasingly encouraged, since they have a high concentration of nutrients. However, these foods are often grown in the presence of agrochemicals, such as fertilizers and pesticides. To increase crop productivity and achieve high vigor standards in less time, farmers make excessive use of agrochemicals that generate various economic, environmental, and clinical problems. In this way, bionanotechnology appears as an ally in developing technologies to improve planting conditions, ranging from the health of farmers and consumers to the production of new foods and functional foods. All these improvements are based on the better use of land use in synergy with the lowest generation of environmental impacts and the health of living beings, with a view to the study and production of technologies that take into account the concept of One Health in its processes and products. In this review article, we will address how caring for agriculture can directly influence the quality of the most desired foods in contemporary society, and how new alternatives based on nanotechnology can point to efficient and safe solutions for living beings on our planet.
... Examples of higher-value alternatives for by-product use include the production of hydrolysates for human consumption, fish mince, fish smoked sausages, fish patties (Erasmus et al., 2021), and aquafeeds (Saleh et al., 2020). The use of by-products for the production of fertilisers and biostimulants has also received attention over the years as a means to increase the economic and ecological sustainability of the fishing industry (Ahuja et al., 2020), by finding avenues to derive value from bones, heads (Kim et al., 2010), viscera (Kim, 2011), and even the wastewater from processing and effluent from aquaculture farms (Ching and Redzwan, 2017;Hayes and Gallagher, 2019). ...
... The resulting biorefined products are widely used as feed ingredients in aquaculture for different aquaculture species. During silage processing, endogenous enzymes hydrolyse proteins and transform them into more soluble forms of nitrogen, this helps contribute to their widespread use (Ahuja et al., 2020;Herpandi et al., 2011;Mousavi et al., 2013). ...
There is a growing concern among societies and consumers over food security and the sustainability of food production systems. For seafood, it has been highly advocated as a healthy food source and its sustainability credentials. However, the increasing global demand for seafood and the need to supply the quantities are creating sustainability issues, e.g., the importation of plant and marine proteins for aquafeed production. Consequently, there is a necessary need to analyse the supply chain and life cycle of these systems to determine their sustainability merits and how to enhance them. The circular economy (CE) aims to reduce processing by-product underutilisation, increase the rate of reuse, and reduce pressure on natural resources and systems. For seafood, there are large quantities of biomass that are being lost through bycatch/discards, waste from aquaculture (e.g., sludge and wastewater), and by-products generated through processing (e.g., trimmings and offal). These can all be valorised for the generation of feeds, value-added products, or further food production. This review will focus on seafood by-products generated during the processing into consumer products, and the current methods that could be used to manage or treat these waste streams. The review presents a stepwise framework that outlines valorisation opportunities for seafood by-products. This framework can enable producers, operators, regulators, and investors to integrate with the principles of the CE with the consideration of achieving economic viability. The challenges of seafood loss due to climate change and emerging recycling strategies will also need to be considered and integrated into the valorisation pathways. Communication, education, and engagement with stakeholders are key to transitioning to a circular economy. Where increase awareness and acceptance will create drivers and demand for seafood by-product valorisation. Overall, the impact of such a circular production system will potentially lead to higher production efficiency, reduce demand for natural resources, and greater seafood production. All of which addresses many of the United Nation's Sustainable Development Goals by contributing towards future food security and sustainability.
... Factors such as pH, moisture, bulk density, and the carbonto-nitrogen (C/N) ratio need to be monitored to achieve successful composting (Ahuja et al., 2020). Special conditions of moisture and aeration are needed to produce thermophilic temperatures (Haug, 2018). ...
... This C/N ratio is often much higher than that of seafood wastes, owing their high nitrogen concentrations. To solve this, seafood wastes can be mixed with bulking agents, such as woodchips, sawdust, wood shavings, bark, crop residues, rice hulls, leaves, crushed grass, wheat bran, and straw (Ahuja et al., 2020). This helps to improve composting performance, not only by adjusting the C/N ratio, but also by absorbing odor and improving the porosity and aeration conditions (Laos et al., 2002;Ros, García, & Hernández, 2006). ...
... Factors such as pH, moisture, bulk density, and the carbonto-nitrogen (C/N) ratio need to be monitored to achieve successful composting (Ahuja et al., 2020). Special conditions of moisture and aeration are needed to produce thermophilic temperatures (Haug, 2018). ...
... This C/N ratio is often much higher than that of seafood wastes, owing their high nitrogen concentrations. To solve this, seafood wastes can be mixed with bulking agents, such as woodchips, sawdust, wood shavings, bark, crop residues, rice hulls, leaves, crushed grass, wheat bran, and straw (Ahuja et al., 2020). This helps to improve composting performance, not only by adjusting the C/N ratio, but also by absorbing odor and improving the porosity and aeration conditions (Laos et al., 2002;Ros, García, & Hernández, 2006). ...
... On the other hand, fish waste-based fertilizers have become a premium product in some Western European countries, having developed their niche in the organic farming supplies market. 24 Some of those products also enjoy premium price among Czech hobbyists and gardeners. For example, these liquid fertilizers are priced between 8 and 14 € L À1 . ...
... Slaughterhouse offal can contribute to fish fertilizers, even creating a niche industry. For example, the potential of fish and fish waste-based fertilizers in EU organic farming; provides a much-needed substitute for poultry manure (reviewed in Ahuja et al. 24 ). ...
Biomass losses and circularity of aquaculture farm-to-fork are reviewed in this article, taking the example of an economically developed but land-locked territory in Central Europe. We found that some waste valorization channels of locally farmed and slaughtered fish biomass are already functioning in the region (mostly for pet food, hunting bait). There is neither control nor information on how much local aquaculture farm-to-fork losses are upcycled to the local human food chain. Despite most of them qualify in ‘category-3’ animal by-products (useable for aquafeed) or preventable losses. Factors to improve farm-to-fork resource use efficiency ‘locally’ include: (a) ‘at farm’ (supplementary feeding, captive culture conditions, fat content, breed, rested harvest techniques, harvesting season); (b) ‘towards fork’ (purging duration, acclimatization before slaughtering, stunning efficacy, bleeding and filleting relative to rigour mortis, additive-based cleaning, pre-cooling, boned or deboned, grinding or baadering); (c) ‘at fork’ (coating- or GRAS additives-based preservation, packaging, modern hurdle systems, freezing rate, interferences of freezing apparatus or packaging on freezing, storage temperature). From farm-to-fork, it is essential to understand that most fish processing by-products can be made edible or valuable by other means. Better utilization strategies exist via low-cost value-added fish products, innovative dishes or utility products (e.g., feedstuff, fertilizers, industrial products, luxury items). Although upcycling to human food chain is priority, technological hurdles (prone to spoilage, bones in product, taste, safety) are associated with edible products but are solvable. More difficult things to overcome are at the fork (culinary industry, communication with society, future generations). Those are reviewed.
... 2. Treatment 3 which was 50% fish scale and 50% fish water waste had the highest mean in height, girth, and length of leaves of corn plants. 3. Treatment 4 which was commercialized fertilizer had obtained the same mean on the number of leaves with treatment 3. 4. Treatment 1 versus among other treatments was highly significant. ...
This study was conducted to determine the effects of fish waste water and fish scale as soil enhancer for the growth of sweet corn. The Experimental Research design with different treatments such as treatment 1 for 100% fish scale, treatment 2 for 100% fish waste water, treatment 3 for 50% fish scale and 50% fish water waste, and treatment 4 for commercialized fertilizer were employed for the growth of corn plants in terms of height, girth of stem, number of leaves and length of leaves. Mean and Post hoc analysis were used for the data analysis. It was found out that treatment 3 which was 50% fish scale and 50% fish water waste and treatment 4 which was commercialized fertilizer had the highest average growth of corn plants in all parameters. However, 100% fish scale and 100% fish water waste had the lowest average growth of corn plants in all parameters. Meanwhile, it was found out also that there was a highly significant difference in the effect of treatment 1 as contrasted among the other treatments of fertilizer. The same with treatment 2 as contrasted with treatment 3 and 4. However, the analysis found no significant difference on the effect of treatment 3 and 4 on the growth response of corn plants in all parameters.
... The lowest value on the ecological dimension was Y1.5 of 6.91% on the role of the farmer group members in contributing to the utilization of livestock manure. Based on the field condition, it was found that most of farmer group members who were the One Thousand Cattle Village Program recipients knew the benefits of livestock manure into biogas and organic fertilizer (Ahuja et al., 2020;Feng and Zhao, 2020). However, due to the lack of assistance, they did not know how to operate the biogas installations that had been built, so they became neglected (Aivazidou and Tsolakis, 2021;Arb et al., 2020). ...
... Companies like Bioretur AS process fish sludge from fish farms for production into a dry product that can be applied, for example, as a fertilizer [53]. However, standards for "certified organic" farming often prohibit the use of fish sludge as a fertilizer, which can also limit export potential to other european countries [61] [62]. According to their website, Bioretur also provides the farms with reports on the contents of the sludge (i.e. ...
Negative emissions have been highlighted as a key component of achieving the net-zero ambition. However, ground-up approaches are necessary to better understand the realistic potential of negative emissions technologies at the national or continental level. Such an approach was applied in the present study to bioenergy with carbon capture and storage in Norway, starting from mapping and quantification of biomass until the derivation of a window of negative emission potential. The results indicate that bioenergy with carbon capture and storage could enable between 1 and 13 MtCO2/y of negative emissions, with a more probable range between 2 and 8 MtCO2/y at least in the coming decades. These values are drastically higher than the potential identified in previous studies thus highlighting the importance of bottom-up approaches, like the one adopted here, to better estimate the potential negative emissions from bioenergy with carbon capture and storage. In terms of biomass, the strongest potential comes from the integration of forestry resources and activities with bioenergy with carbon capture and storage. This potential can be significantly increased if a "bioenergy with carbon capture and storage"-driven expansion of forestry biomass harvesting takes place. However, it is important to ensure that it takes place in a sustainable way and does not result in a decrease in the standing volume of the Norwegian forest for multiple reasons. Integrating waste with bioenergy with carbon capture and storage also represents a significant potential, especially as a substantial fraction is already integrated with energy production Finally, biomasses from agriculture and seaweed farming are expected to have a limited potential, although seaweed farming could take a more significant role toward the second half of the century, depending on the development of this sector.
... On the flip side, the generation of fruits and vegetables has increased exponentially in recent years because human society has begun to consume healthier food, resulting in an economic boost for agro-industrial companies that export these products [8]. However, this increase in production has also generated large amounts of organic waste (agro-industrial waste), which has become a problem for governments because they do not have an organized method of collecting and managing this type of waste [9,10]. It has been reported that municipal waste in 2017 in Europe was 58 million tons, of which 46% was organic waste, which is estimated to increase by 32% by 2030 [11]. ...
This research used tomato waste as a substrate (fuel) in Single Chamber-Microbial Fuel Cells (scMFC) on a small scale. The electrochemical properties were monitored, the functional groups of the substrate were analyzed by Fourier Transform Infrared Spectrophotometry (FTIR) and a microbiological analysis was performed on the electrodes in order to identify the microorganisms responsible for the electrochemical process. The results show voltage peaks and an electrical current of 3.647 ± 0.157 mA and 0.957 ± 0.246 V. A pH of 5.32 ± 0.26 was measured in the substrate with an electrical current conductivity of 148,701 ± 5849 mS/cm and an internal resistance (Rint) of 77. 517 ± 8.541 Ω. The maximum power density (PD) displayed was 264.72 ± 3.54 mW/cm2 at a current density (CD) of 4.388 A/cm2. On the other hand, the FTIR spectrum showed a more intense decrease in its peaks, with the compound belonging to the phenolic groups being the most affected at 3361 cm−1. The micrographs show the formation of a porous biofilm where molecular identification allowed the identification of two bacteria (Proteus vulgaris and Proteus vulgaris) and a yeast (Yarrowia lipolytica) with 100% identity. The data found show the potential of this waste as a source of fuel for the generation of an electric current in a sustainable and environmentally friendly way, generating in the near future a mechanism for the reuse of waste in a beneficial way for farmers, communities and agro-industrial companies.
... In some types of fish, for every ton taken, about the same quantity of waste is wasted either by ocean dumping or land disposal (Illera-Vives et al., 2015). Furthermore, the use and subsequent fish processing waste are determined by local conditions and industrial structure (Ahuja et al., 2020). Fish waste can also be converted into proteins, amino acids, peptides, collagen, oil, minerals, enzymes, flavors, and other substances used in food, feed, and medicinal applications (Ghaly et al., 2013;Eilertsen et al., 2017). ...
Channa striata is a freshwater fish commonly found in Asia. Recently, the number of catches and aquaculture products has increased along with their uses. This fish is widely used for food and traditional medicinal products in Indonesia, and its high usage has resulted in a large amount of waste. Therefore, this study aims to determine the potential fatty acids nutrition of snakehead fish waste. Gas Chromatography Flame Ionization Detector (GC-FID) was used to analyze the fish's head, intestine, skin, bone, fins, and tail according to their fatty acid profiles. Additionally, the moisture, protein, ash, and lipid contents were also conducted. The results showed that the proximate content of channa waste still contains 17.09-19.02% protein, 2.45-4.26% lipid, 7.05-16.42% moisture, and 1.30-30.18% ash. Furthermore, the total amount of EPA and DHA detected was 0.19% and 7.97% in the head, 3.93% and 6.84% in the innards, 0.1% and 9.41% in the bones, 0.1% and 9.83% in the fins and tail. In conclusion, the fatty acid profile of snakehead fish waste shows that it can be used for feeding purposes by both humans and animals.
... Fish waste silage has been proven to serve as a biofertilizer and animal feed through lactic acid fermentation. This process effectively minimizes the fishy odor and harmful bacteria in fish waste, thus presenting a sustainable alternative for agriculture and animal husbandry [118]. Sustainable seaweed biorefineries have been investigated. ...
The management of biowaste and agricultural solid waste is gaining attention due to rising landfill disposal costs and the need for locally available agricultural feedstocks. The biorefinery concept aims to achieve zero waste through valorizing residues as fertilizers. Despite containing NPK macronutrients, residues may not promote plant growth due to limited nutrient availability and phytotoxic compounds. The production of valuable organic, mineral-organic, or mineral fertilizers with confirmed agronomic properties as marketable biorefinery products remains understudied. This comprehensive review broadens our understanding of fertilizer production in biorefineries, which complements the energy (thermal, biogas, biodiesel) and chemical compounds (e.g., succinic acid, propanediol, protein concentrates) that are also generated within biorefineries. It is among the first reviews to investigate the importance of valorizing biorefinery residues as fertilizers, emphasizing methods leading to commercial products and the rationale behind this process. The findings confirm that directly applying unprocessed residues to the soil does not fully exploit their value as by-products. This study contributes to the practical analysis of barriers (legal, chemical, biological, technological) and opportunities (rising prices and reduced global availability of mineral fertilizers) related to fertilizer production in the biorefining process.
... "The seafood processing plant and capture fisheries produce huge amount of solid waste. The waste from fishes are viscera, offal, skin, scales, shells and other body parts are rich in variety of plant nutritive elements and devoid of hazardous contaminants and pathogens" [5]. "Disposal of solid waste generated from seafood processing plant has always been a problem for seafood processors. ...
Seafood is gaining in popularity because of its health benefits. At the same time, large amounts of fish waste are being generated, mostly from the industrial processing of fish. These large quantities of fish waste have not been utilized efficiently, and the disposal of fish waste can have large negative impacts on local environments. Unutilized fish waste is often disposed of by land fill or incineration, or by dumping into the sea. Therefore, there is an urgent need to find ecologically acceptable means for reutilization of fish waste. In this study, fish waste samples are collected and characterised. The fish waste was acidic in pH (6.1) with EC of 3.8 dSm-1. The total N, P, K of the fish waste was 10.17, 0.20 and 0.74 % respectively. It also had an appreciable amount of organic carbon content 46.22%. Fish waste was mixed with saw dust (2:1) and Rock Phosphate - Phosphorus (RP-P) at the rate of 0, 2.5, 5, 7.5 and 10 % for enrichment of compost The results showed that the application of different levels of (RP-P) reduce the pH, slightly increased the EC, N,P,K and Organic carbon content. Thus, rock phosphate enriched fish waste compost could be an alternative and viable technology to manage the solid waste generated from the seafood industries as well as crop production.
... Enormous quantities of waste is generated from fish processing industries and fish markets (24-27% of head, 12% bones, 3% skin, 12% visceral organs including eggs, blood, and scales), constituting about 30-70% of the original weight of the fish which is unhealthy for human consumption but has other potential uses [1][2][3][4][5][6][7][8][9]. Since such kinds of waste if not handled aptly, get spoiled, thus contributing to environmental contamination [3,4,6,10,11]. ...
Fish silage is a liquefied product resulting from tissue hydrolysis and the richness of the silage is characterized by its nutritional profile comprising of proteins, amino acids, and fats. For the production of fish silage of high nutritional value, a precise assessment of the degree of hydrolysis, particularly proteolysis becomes a paramount importance. The goal of this study is to assess the changes in protein content in fish silage prepared from the Indian mackerel (Rastrelliger kanagurta) waste using 10% (v/w) sugarcane molasses, during 8 days of fermentation (DoF). The resultant ensiled product was evaluated for changes in titratable acidity, nutrients, total protein, total carbohydrate, total lipids content, and amino acid composition. Altogether, 17 types of amino acids were identified. Concentrations of total amino acids (TAAs, 15.627 ± 0.03 mg/g) and free amino acids (5.556 ± 0.08 mg/g) peaked at the end of 6 DoF with the predominance of histidine, arginine, alanine, asparagine, aspartic acid, and glutamic acid. Results of the non-metric multidimensional scaling (nMDS) plots and one-way analysis of similarities (ANOSIM) test indicated significant differences in the composition of TAAs at different DoF were discernible (nMDS, stress 0.03162, one-way ANOSIM R = 1; p < 0.0001). Similarity percentage (SIMPER) analysis indicated that the maximum content of amino acids (TAA and FAA) were released in silage during 4–6 DoF. A significant difference was observed in concentrations of most amino acids except cysteine, serine, and tryptophan (ANOVA, p < 0.05) at 2, 4, 6 and 8 DoF. Considering the vital role played by amino acids in providing resistance to plant pathogens as well as contributing to animal nutritional supplements, the results of the present study are highly noteworthy.
Graphical Abstract
... From a biological function perspective, they are considered to exhibit antioxidant, antimicrobial, anti-hypertensive, antiproliferative, and immunomodulatory activities [3][4][5][6]. Although several fish side streams have been reported to contain relevant amounts of minerals over the last years [7][8][9], these elements are not usually analyzed in fish protein hydrolysates and related products. For instance, Liaset and Espe reported high levels of potassium in protein hydrolysates from salmon and saithe side streams [10]. ...
Information on the bioaccessibility of minerals is essential to consider a food ingredient as a potential mineral fortifier. In this study, the mineral bioaccessibility of protein hydrolysates from salmon (Salmo salar) and mackerel (Scomber scombrus) backbones and heads was evaluated. For this purpose, the hydrolysates were submitted to simulated gastrointestinal digestion (INFOGEST method), and the mineral content was analyzed before and after the digestive process. Ca, Mg, P, Fe, Zn, and Se were then determined using an inductively coupled plasma spectrometer mass detector (ICP-MS). The highest bioaccessibility of minerals was found in salmon and mackerel head hydrolysates for Fe (≥100%), followed by Se in salmon backbone hydrolysates (95%). The antioxidant capacity of all protein hydrolysate samples, which was measured by Trolox Equivalent Antioxidant Capacity (TEAC), increased (10–46%) after in vitro digestion. The heavy metals As, Hg, Cd, and Pb were determined (ICP-MS) in the raw hydrolysates to confirm the harmlessness of these products. Except for Cd in mackerel hydrolysates, all toxic elements were below the legislation levels for fish commodities. These results suggest the possibility of using protein hydrolysates from salmon and mackerel backbones and heads for food mineral fortification, as well as the need to verify their safety.
... Likewise, it is estimated that the waste from agro-industries reaches between 5 and 10% per year, and these wastes in developing countries are dumped into the environment without an adequate protocol, generating pollution in the environment and harmful effects on human health [7][8][9]. For this reason, large research centers have made proposals on the potential uses that can be given to these types of waste, with the production of biogas, compost, nutritional supplements, biomaterials, and bioelectricity being the most researched [10,11]. ...
This research aimed to use kiwi waste as fuel to generate bioelectricity through microbial fuel cells. It was possible to generate an electrical current and voltage peaks of 3.807 ± 0.102 mA and 0.993 ± 0.061 V on day 11, showing an electrical conductivity of 189.82 ± 3.029 mS/cm and an optimum operating pH of 5.966 ± 0.121. The internal resistance of the cells was calculated using Ohm’s Law, resulting in a value of 14.957 ± 0.394 Ω, while the maximum power density was 212.68 ± 26.84 mW/m2 at a current density of 4.506 A/cm2. Through the analysis of the FTIR spectra carried out on the substrate, a decrease in the characteristic organic peaks was observed due to their decomposition during the electricity-generation process. In addition, it was possible to molecularly identify the bacteria Comamonas testosteroni, Sphingobacterium sp., and Stenotropho-monas maltophila adhered to the anodized biofilm. Finally, the capacity of this residue to generate bioelectricity was demonstrated by lighting an LED bulb with a voltage of 2.85 V.
... Most of the approaches for fish waste utilization include the recovery of protein and other essential biomolecules, and as aquaculture and agricultural fertilizers. A review on fish-waste-based fertilizers used in organic farming revealed that fish and fish waste are useful raw materials for developing good-quality solid and liquid fertilizers, and digestates [30]. On the other hand, fish waste is also utilized as an ingredient in food supplements, and recent updates on the sustainable recovery of omega-3 fatty acids in fish waste revealed several extraction methods. ...
Bioactive peptides derived from fish the byproduct protein hydrolysate have wide potential as functional food ingredients. The preparation of bioactive peptides is commonly achieved via enzymatic hydrolysis; this is the most preferred method because it has high specificity, fewer residual organic solvents in the product, and it is usually carried out in mild conditions. The use of various enzymes such as proteases is widely practiced in the industry, yet there are various limitations as it is of high cost and there is a limited availability of food-grade enzymes in the market. Moreover, high-throughput purification and the identification analysis of these peptides are currently being studied to further understand the functionality and characterization of the bioactive peptides. This review mainly focuses on the novel bioactive peptides derived from fish protein hydrolysates from various fish wastes and byproducts. The hydrolysis conditions, source of hydrolysate, and amino acid sequence of these novel peptides are presented, along with their corresponding methods of analysis in purification and identification. The use of various enzymes yields novel peptides with potent bioactivities, such as antiproliferative, antimicrobial, antihypertensive, antiglycemic, antitumor, and antioxidative biological functions. The increasing interest in proteomics in marine and aquatic waste utilization continues due to these products’ bioactivity and sustainability.
... Marine residual materials from the fish and seaweed industry, which are currently underutilized, should be considered for the development of organic fertilizers. Fish residues, which are rich in nitrogen (N), phosphorus (P), and calcium (Ca), can be very valuable as fertilizers [25][26][27]. Rosadi and Catharina [27] reported that a liquid organic fertilizer prepared from Skipjack tuna residue, which was applied at a concentration of 3.5 mL/L water, enhanced the vegetative growth of strawberry plants. Macroalgae contain N, P, Ca, potassium (K), sodium (Na), magnesium (Mg), and sulfur (S), and they are also rich in micronutrients needed by plants, especially iron (Fe), manganese (Mn), and zinc (Zn) [18]. ...
An outdoor experiment was performed for six months to evaluate the effects of organic fertilizers obtained from marine residual materials on strawberry plants. Three types of organic fertilizers were used, i.e., cod (Gadus morhua) bone powder, common ling (Molva molva) bone powder, and pellets obtained by mixing small cod bone powder and rockweed (Ascophyllum nodosum) residues. A tabletop system for strawberry cultivation was designed, in which two bare-root strawberry plants of cultivar ‘Albion’ were planted in a peat substrate in each pot. Five treatments were applied, i.e., cod bone powder (F1), common ling bone powder (F2), small cod bone powder and rockweed residue pellets (FA), chemical fertilizer (E), and a control (C). The number of leaves and their nutrient content, fruit yield and quality characteristics of the strawberries grown using the organic fertilizers were similar or better than those corresponding to treatments E and C. Organic fertilizers derived from the residues of fish and macroalgae could be a promising alternative to chemical fertilizers in strawberry production.
... Kriteria dasar untuk memutuskan pemilihan sumber protein alternatif meliputi kandungan gizi, tingkat kecernaan, ketersediaan, dan harga (He et al., 2022). Sementara itu, ketersediaan limbah ikan yang melimpah telah diteliti dapat menjadi pengganti pakan ikan karena kaya protein (Ahuja et al., 2020;Mo et al., 2018;Wang, 2021). Limbah ikan adalah kondisi kehilangan ikan pasca-tangkap dan menjadi konstituen terbesar dari limbah padat yang berasal dari lautan (Tugiyono et al., 2020). ...
Demand for fish pond cultivation is rising, but the cost of fish feed is also increasing. A modified double-edged blade chopper machine was developed to make fish feed from abundant fish waste. An experiment was conducted to assess its efficiency and feasibility. An experimental investigation was carried out to assess the efficiency and techno-economic feasibility of the modified double-edged blade chopper machine at Margo Mulyo Abadi SME, which has abundant fish waste and extensive pond fish farming. Efficiency research data collection was conducted for 4-5 replications using dry and wet fish waste. The production cost of the double-edged blade chopper machine was calculated to determine its affordability. The research results showed that the speed of making fish feed from wet fish waste was slower than that of dry fish waste, whether using manual or double-edged blade chopper machine cutting. The machine is faster than manual cutting, with a capacity of up to 210 kg/h. Its production cost is affordable. The double-edged blade chopper machine was measured and obtained a REBA score of 3, while manual cutting had a REBA score of 8. The machine is recommended due to its high efficiency, low production cost, and safety. Abstrak Permintaan ikan budidaya tambak semakin meningkat dan bervariasi, tetapi mahalnya pakan ikan untuk pemenuhan nutrisi ikan budidaya tambak semakin meningkat. Modifikasi mesin pencacah ganda dikembangkan dan diteliti untuk meningkatkan produktivitas pembuatan pakan ikan dari limbah ikan yang melimpah. Investigasi eksperimental dilakukan dengan mengombinasikan analisis efisiensi dan tekno-ekonomi modifikasi mesin pencacah ganda di UMKM Margo Mulyo Abadi. Pengambilan data penelitian efisiensi dilakukan sebanyak 4-5 replikasi dengan menggunakan limbah ikan kering dan limbah ikan basah pada pemotongan manual dan mesin pencacah ganda sebagai perbandingan. Biaya produksi mesin pencacah ganda diperhitungkan untuk menentukan keterjangkauan mesin yang diusulkan. Hasil penelitian menunjukan bahwa kecepatan pembuatan pakan ikan dari limbah ikan basah lebih lama dibanding limbah ikan kering baik menggunakan pemotongan manual maupun mesin pencacah ganda. Mesin pencacah ganda jauh lebih cepat daripada pemotongan manual dalam membuat pakan ikan dari limbah ikan basah dan kering. Kapasitas yang dihasilkan menggunakan mesin pencacah ganda adalah 210 kg/jam dibandingkan hanya 15 kg/jam dengan pemotongan manual. Mesin pencacah ganda diukur dan didapatkan skor REBA 3 berisiko rendah sedangkan pemotongan manual mempunyai skor REBA 8 berisiko tinggi. Kelayakan penggunaan dan ekonomi mesin ini direkomendasikan karena rendah biaya produksi dan aman dalam penggunaannya. Kata Kunci: pakan ikan, limbah ikan, mesin cacah, efisiensi, tekno-ekonomi PENDAHULUAN Sektor perikanan laut dan tawar memberikan peran signifikan secara kuantitas sebagai sumber nutrisi penting kesehatan manusia karena tinggi protein, vitamin esensial, mineral, asam lemak, dan kandungan lainnya (Banna et al., 2022). Selain itu, pemenuhan kebutuhan sektor perikananan menjadi semakin bervariasi dan penting bagi konsumen (Sangirova et al., 2020). Hal tersebut diperkuat dengan laporan terbaru dari Food and Agriculture Organization (FAO, 2022), total produksi perikanan di dunia relevan dengan peningkatan kebutuhannya yaitu mencapai 214
... Viscera, gills, and scales make up a large portion of the fish waste obtained from wet markets in Metro Manila and rural areas (Fig. 4). The responses of the respondents match the same categories that indicate parts of a dead fish that have little to no commercial value (Ahuja et al. 2020) and are generally classified as "fish waste" in the fisheries industry. Majority of fish vendors produced fish waste every day (96.4%). ...
Improper management of fish waste is one of the factors that makes Philippine fisheries unsustainable. A considerable portion of fish waste is produced in wet markets where bulk of fish products are sold. A comparison of existing practices in different municipalities can indicate the best points of intervention and identify existing traditional practices that can be promoted. This study interviewed stakeholders of the fisheries industry and collected information at the market level to determine existing fish waste management systems. From the responses gathered, the average daily production of fish waste in Philippine wet markets was 70.3 + 0.93 kg, with no significant differences across locations (p = 0.2501). Of the fish waste produced, 32.3 + 1.33 kg per wet market were disposed of, 18.9 + 0.81 kg were sold, and 19.1 + 1.15 kg were given away to stakeholders who re-use the fish waste. A significantly greater proportion of fish waste in rural areas were re-used compared to Metro Manila (p = 0.0311). Incentivizing innovations that maximize the use of derived fish waste at the municipal level, and promoting existing traditional practices, can prove effective in contributing to the Philippine circular economy while providing alternative sources of income for the stakeholders of the fisheries industry.
... Las plantas requieren al menos 14 elementos minerales para su nutrición: los macronutrientes nitrógeno (N), fósforo (P), potasio (K), calcio (Ca), magnesio (Mg) y azufre (S) y los micronutrientes cloro (Cl), boro (B), hierro (Fe), manganeso (Mn), cobre (Cu), zinc (Zn), níquel (Ni) y molibdeno (Mo) (While y Brown, 2010). El fertilizante líquido de pescado es una buena fuente de nitrógeno, fósforo y proteína, que son nutrientes esenciales en las plantas (Suartini et al., 2018;Ahuja et al., 2020). De acuerdo con Palacin (2017) este fertilizante tiene un contenido de 7,112 g/L de N, 0,517 g/L de P y 1,945 g/L de K, mientras que para Pereira et al. (2020a) el contenido es de 10,7 g/L de N, 14,0 g/L de P y 1,3 g/L de K, con adecuadas cantidades de macro y micronutrientes que son fácilmente disponibles y asimilados por las plantas. ...
El fertilizante líquido de pescado es buena fuente de nitrógeno, fósforo y proteína que son nutrientes esenciales en las plantas, el hydropriming implica remojar las semillas en agua y secarlas, para mejorar su germinación. Un porcentaje de las semillas de quinua y cañahua del Banco de Germoplasma de Granos Andinos, tienen baja germinación, en ese sentido, el objetivo de la investigación es evaluar el efecto del Hydropriming y fertilizante líquido de trucha en el incremento de la germinación y crecimiento radicular en semillas de quinua y cañahua. La investigación se desarrolló en el laboratorio Banco de Germoplasma de Granos Andinos (Bolivia). Se tomó una muestra de 100 semillas de tres accesiones de quinua y cañahua, se evaluaron cuatro tratamientos: testigo (100%:0%), tratamiento 1 (99,90%; 0,10%), tratamiento 2 (99,75%;0,25%), tratamiento 3 (99,50%;0,50%) y tratamiento 4 (99,25%;0,75%) con tres repeticiones, el tiempo de remojo fue 12 horas a temperatura ambiente, después fueron secadas y dispuestas en cajas Petri, luego se introdujeron a la cámara germinadora durante siete días a una temperatura de 17°C, la longitud de la radícula (mm) fue determinada mediante un vernier electrónico. La combinación de 99,50% de agua destilada con 0,25% de fertilizante líquido de trucha es el óptimo para alcanzar mayor porcentaje de germinación y longitud radicular en semillas de quinua y cañahua. La combinación de 99,25% de agua destilada con 0,75% de fertilizante líquido de trucha reflejó disminución en ambas variables, que según investigaciones similares es debido al incremento del pH y disminución de la CE.
... Pemanfaatan air dari budidaya ikan nila untuk penyiraman tanaman merupakan upaya dalam rangka meningkatkan kesuburan tanah. Hal ini dikarenakan air budidaya ikan mengandung bahan organik yang berasal dari kotoran ikan (Ahuja et al., 2020). Selain itu penerapan model pertanian berkelanjutan yang dijalankan adalah pemanfaatan perbedaan tekanan sehingga penyiraman air tidak menggunakan energi listrik. ...
Desa Sukanagalih terletak di Kecamatan Pacet Kabupaten Cianjur Jawa Barat. Pekerjaan sebagian besar penduduknya adalah petani yang menghasilkan beberapa komoditas unggulan seperti wortel, daun bawang, tomat, kol, kembang kol, brokoli dan pakcoy. Pembangunan wisata Taman Bunga Nusantara tahun 1995 merubah sebagian mata pencaharian penduduknya yang awalnya sebagai petani beralih menjadi pelayanan di bidang jasa pariwisata. Pandemi Covid-19 pada tahun 2020 hingga 2022 kembali memberikan dampak terhadap sosial ekonomi masyarakat desa Sukanagalih karena terjadi penurunan aktifitas industri pariwisata. Akibatnya sebagian masyarakat yang berusaha di bidang jasa pariwisata kembali beralih menjadi petani. Akan tetapi usaha di bidang pertanian menghadapi tantangan yaitu penurunan produktifitas hasil pertanian yang disebabkan berkurangnya kesuburan tanah akibat perubahan iklim. Tujuan pengabdian masyarakat yang dilakukan oleh UAI adalah untuk meningkatkan kompetensi pemahaman ketua kelompok tani mengenai model pertanian berkelanjutan dalam meningkatkan produktifitas hasil pertanian dan pemasaran di era digital. Metode yang digunakan adalah sosialisasi dalam bentuk workshop dan demonstrasi kepada 30 orang ketua kelompok tani. Materi yang disampaikan adalah model pertanian berkelanjutan termasuk cara pembuatan pupuk organik cair (POC) serta pemasaran digital hasil pertanian. Tanaman sayuran yang dijadikan contoh adalah Brassica rapa L. (Pakcoy). Hasil pengabdian masyarakat menunjukkan peningkatan kompetensi pemahaman ketua kelompok tani mengenai model pertanian berkelanjutan dan pemasaran digital hasil pertanian. Persentase ketua kelompok tani yang memahami model pertanian berkelanjutan dan pemasaran digital sebelum dilaksanakan pengabdian kepada masyarakat adalah 27,77 dan meningkat setelahnya menjadi 65,22. Walaupun terdapat peningkatan pemahaman ketua kelompok tani namun sosialisasi dalam bentuk workshop dan demonstrasi masih perlu diberikan secara berkelanjutan
... Fish wastes have the potential of supplying a combination of nitrogen and phosphorous for horticulture plants. Ahuja et al. (2020) have certified that the anaerobic digestion of fish waste was applicable for organic farming. Simultaneously, 250 g of sliced raw papaya and jaggery pieces were added and mixed well. ...
Use of liquid organic fertilizers is popular among container gardeners in urban areas. The impact of five organic liquid fertilizers (banana waste, weeds, Gliricidia leaves, fish waste, and cow dung) Albert's solution (control) on growth and yield of three test crops of Abelmoschus esculentus, Raphanus sativus and Amaranthusspp were studied in the present study. Three separate experiments were laid out as randomized complete block designs with six replicates. The effect of treatments on plant growth and yield of Abelmoschus esculentus was significant. Treatment 1, 2 and 3 recorded the greatest fresh weight of pods in okra (p < 0.0001). Treatments used in the study significantly influenced the average plant height, fresh weight of leaves, diameter, length and weight of the tuberous root of Raphanus sativus. Albert's solution and cow dung liquid fertilizer treated plants produced the tuberous roots with the greatest diameter (p < 0.0001) and length (P=0.015) while the plants that received Gliricidia leaves liquid fertilizers recorded the least values. Furthermore, the highest and lowest tuberous root fresh was reported by cow dung liquid fertilizer and Gliricidia leaves liquid fertilizer, respectively. There was a significant difference between treatments for the average plant height (p < 0.0001), number of leaves (p =0.0006), leaf length (p =0.03), leaf width (p < 0.0001), stem girth (p < 0.0001) and root length (p =0.0001) of Amaranthus spp. Nevertheless, the volume of the roots per plant was not significantly different among treatments. As per the results of the present study, it could be concluded that the banana and weeds liquid fertilizer could be used as same as Albert's solution for Abelmoschus esculentus while cow dung liquid fertilizer influenced the growth and yield of Raphanus sativus in container gardening. Vegetative growth and economic yield of Amaranthus spp. can be achieved by applying Albert's solution, banana, weed and fish liquid fertilizers. Selected types of organic liquid fertilizers could be used to replace Albert's solution for short-term vegetable crops. However, the performance of the liquid fertilizer might be affected by the size, shape and colour of the containers used for gardening as well as the quality of the potting mixture.
... Nutrien komponen pupuk organik pada limbah ikan seperti nitrogen (N), fosfor (P), dan kalium (K) masih tinggi (Hapsari & Welasih, 2011;Toppe & Penarubia, 2018;Ahuja et al., 2020). Residu hasil pengolahan minyak ikan teri mengandung karbon 40%, nitrogen 12%, kalium 5,5 mg/g, kalsium 35,2 mg/g, dan fosfat 5,6 mg/g (Muscolo et al., 2022). ...
... Global scenario in the realms of both culture and capture fisheries holds great promise in boosting the economy along with livelihood generation, especially in several developing countries of the world (Ahuja et al., 2020;Garlock et al., 2020;Kazemi et al., 2017). The entire world had viewed an enormous fish production of 178.5 million tons in the year 2018, which had accounted a surplus of 2%-4% over last decade (Aster, 2018;FAO, 2020). ...
This chapter provides comprehensive information on organic waste pathogen reduction using insect larvae, mechanisms of pathogen suppression during entomocomposting, and the contribution of insect frass fertilizer to improving soil fertility and crop productivity in an environmentally sound, socially just, climate-resilient, and cost-effective manner. Finally, we provide concluding remarks and key recommendations on sustainable utilization of entomocomposting for waste management and fertilizer production. This knowledge will guide investors, entrepreneurs, and farmers who wish to use insects for waste recycling, environmental cleanup, and fertilizer generation to achieve sustainable development goals.
... Regarding the fish wastes, scales are waste material with no important competitive use. Fish wastes are partially used to produce fertilizers and fish oil with low profitability or as raw material for direct feeding in aquaculture [36][37][38][39] and partly thrown away [40]. To overcome the environmental issues and for the full use of biomass for the purposes of high-commercial value, fish wastes were also investigated as a potential resource to produce value-adding products (i.e., proteins, peptides, collagen, enzymes, and oils) [40]. ...
In the present study, the biosorptive potential of Cyprinus carpio scales for the removal of Fe, Mn, and Zn ions from real acidic mine drainage (AMD) generated at the Rosia Montana gold mine (Romania) was explored for the first time. The collected AMD solution is very acidic, and the concentrations of Fe, Mn, and Zn ions exceed more than 34 to 56 times the disposal standards imposed by legislation. Batch adsorption experiments were carried out to study the effect of the sorbent dosage, sorbent particle size, pH, and contact time on the adsorption performance of the fish scales. Before and after the adsorption process, the biosorbent was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, and energy-dispersive X-ray spectroscopy (SEM-EDX). In the investigated experimental conditions, about 100%, 87.1%, and 100% of Fe, Mn, and Zn ions were removed from the AMD after 240 min of contact with the finest-grained Cyprinus carpio scale samples using a solid:liquid ratio of 20:1 (g:L). The adsorption data were analyzed using the pseudo-first order, pseudo-second order, intraparticle diffusion rate, and Elovich equations. The adsorption process was found to follow the pseudo-second-order kinetic model. The maximum adsorption capacities of the fish scales were about 2.46 mg/g for Mn and 0.85 mg/g for Zn ions, respectively. Aside from their significant efficiency in the removal of metals from AMD, Cyprinus carpio scales also have the potential to neutralize the acidic wastewater. Thus, the removal process of metal ions from AMD is ruled by a complex mechanism, including adsorption and iron precipitation. The recycled scales are still able to remove the metal ions from AMD with a better performance during the first regeneration cycle. Based on the obtained results, it might be assessed that the low-cost biowaste of Cyprinus carpio scales have great potential and could be effectively used for the remediation of real acidic mine drainage from a sustainable perspective.
... Fish silage can be used in large-scale production because it is inexpensive and simple and has the main advantage of removing the smell and drainage problems of the industry. The disadvantages of fish silage include consumption at the same production place and high product volumes [152]. Fish silage and fish protein hydrolysates are commonly produced from the digestive organs of fish as well as the spleen and gonads [153]. ...
The global population has rapidly expanded in the last few decades and is continuing to increase at a rapid pace. To meet this growing food demand fish is considered a balanced food source due to their high nutritious value and low cost. Fish are rich in well-balanced nutrients, a good source of polyunsaturated fatty acids and impose various health benefits. Furthermore, the most commonly used preservation technologies including cooling, freezing, super-chilling and chemical preservatives are discussed, which could prolong the shelf life. Non-thermal technologies such as pulsed electric field (PEF), fluorescence spectroscopy, hyperspectral imaging technique (HSI) and high-pressure processing (HPP) are used over thermal techniques in marine food industries for processing of most economical fish products in such a way as to meet consumer demands with minimal quality damage. Many by-products are produced as a result of processing techniques, which have caused serious environmental pollution. Therefore, highly advanced technologies to utilize these by-products for high-value-added product preparation for various applications are required. This review provides updated information on the nutritional value of fish, focusing on their preservation technologies to inhibit spoilage, improve shelf life, retard microbial and oxidative degradation while extending the new applications of non-thermal technologies, as well as reconsidering the values of by-products to obtain bioactive compounds that can be used as functional ingredients in pharmaceutical, cosmetics and food processing industries.
... FPW can also be used to produce fish feed due to the inner high concentration of proteins (Mo et al. 2018); in China, it was estimated that up to 0.65 million tons of fish feed could be produced from FPW annually, accounting for approximately 50% of the total fish feeds demand in 2015 (Cao et al. 2015). Kannan et al. (2018) optimized the conventional hydrothermal carbonization for hydrochar production from FPW. Aquaculture solid waste can be liquified by adding formic acid, endogenous enzymes, or fermenting agents to produce fish silage (Ahuja et al. 2020). Fish scales treated by thermal hydrolysis along with acid have been shown to act as biosorbents to achieve immobilization of heavy metals, alleviating the sediment toxicity in the aquatic systems (Pal and Maiti 2020). ...
Due to the serious environmental pollution and waste of resources resulting from aquaculture solid waste, its treatment and disposal have attracted wide attention in recent years. Aquaculture solid waste mainly consists of aquaculture sludge (AS) and fish processing waste (FPW). This paper reviews the characteristic and environmental impact of AS and FPW, respectively. The conventional and novel technologies for aquaculture solid waste management are analyzed and summarized. Discharged, constructed wetland, aerobic composting, anaerobic treatment, enzymatic or chemical hydrolysis, and aquaponics are conventional and well-known technologies used in aquaculture waste reduction, valorization, and recycling. Novel technologies are mainly applied to recycle resources or produce valuable by-products, including biodiesel, fish silage, biosorbent, hydrochar, lactic acid, hydrogen, and Hermetia illucens larvae growth from FPW, as well as phytoremediation and biofloc technology for AS treatment. Finally, future directions of aquaculture solid waste management are proposed.
... Fish waste and by-products include different materials from fish, such as intestines, fish trimmings, tails, fins, scales, bones, skins, heads and damaged fish bodies [120]. Fish waste and by-products were processed into liquid or solid forms of fertilizers, such as fish soluble fertilizer, fish hydrolysates, fish meal, fish emulsion and fish powder. ...
Sustainable crop production can be achieved by integrating the concept of modern agriculture with hydroponics for plant production and organic agriculture with the use of organic fertilizer as an alternative to the chemical-based nutrient solution. Organic fertilizers contain a significant amount of essential nutrients needed by the plant for growth and development. Various approaches have been studied to test the viability of organic fertilizer as a nutrient source in hydroponics, such as replacing inorganic substrates with organic substrates, partial replacement, and full replacement of chemical-based nutrient solutions with organic fertilizers. Full replacement of nutrient solutions with organic fertilizers is deemed to be the most sustainable approach. However, unlike nutrient solution, which has an established optimum operation parameter, organic fertilizer as a nutrient solution in hydroponics faces several challenges, such as variability of the quality of organic fertilizers, nutrient management and optimization of the operating parameters. This review provides a general overview of the various approaches to utilize organic fertilizer as a plant nutrient source in hydroponics. In addition, this review provides a synthesis of hydroponics and its applicability to sustainable production, nutrient content of commonly used organic fertilizers and chemical-based nutrient solutions, a comparison of the plant growth and quality using organic fertilizer and chemical-based nutrient solutions and important operating parameters on utilizing organic fertilizers in hydroponics.
Brown algae and fish waste contain high-value compounds with potentially beneficial effects on plant growth. Several commercial fertilizer products are currently available, but the characteristics of the materials are usually not well-described. Fish and seaweed residues originating from the Norwegian coast are available, after industrial processing, which may be combined into complete fertilizers exerting additional effects on crop plants (biostimulants). In this study, raw samples of fish and seaweed residues were investigated using ecofriendly technologies (drying, leaching), targeting search and isolation of potential biostimulants, followed by physicochemical characterization (elemental analysis, UV–visible, FT-IR, ICP-MS, ICP-OES, electrical conductivity, pH, etc.). Organic solvent extractions were employed to determine the available mineral content, micro- and macro-nutrients, antioxidant compounds, and amino acid content by chemical hydrolysis. The in vitro biotoxicity profile (cell viability, morphology, migration) of the generated extracts was also perused, employing Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli) along with sensitive neuronal eukaryotic cell lines N2a58 and SH-SY5Y, to assess their time- and concentration-dependent efficacy as antimicrobials and agents counteracting oxidative stress. The analytical composition of all raw materials showed that they contain important nutrients (K, P, Ca, N) as well as organic compounds and amino acids (Gly, Asp, Glu, Leu, Phe) capable of acting as plant biostimulants. Concurrently, the inherently high conductivity values and salt content necessitated leaching processes, which result in Na+ and K+ decreasing by more than ~60% and justifying further their use in soil treatment formulations. The aforementioned results and assertions, combined with physical measurements (pH, electrical conductivity, etc.) on naturally occurring and dried samples as well as green solvent extracts, formulated a physicochemical profile reflecting well-defined inorganic–organic species that might function as biostimulants. The collective physicochemical and biological properties support the notion that appropriate mixtures of marine organism residues may be efficient fertilizers for crop plants and concurrently possess biostimulant characteristics.
Yellowfin tuna (Thunnus albacares) and Asian sea bass (Lates calcarifer) are highly demanded export fish species in Sri Lanka. The objective of the present study was to prepare leather from the skin of T. albacares and L. calcarifer using tanning media prepared with black tea (Camellia sinensis) powder and table salt (NaCl). Black tea powder and table salt concentrations were increased by 10 grams (initial weight; 10 gL-1) and 1 gram (initial weight; 1 gL-1), respectively each day for 12 d. Skins were dipped in each concentration for 24 hrs. After additional water was removed, vegetable oil-applied skins were stretched and air-dried at room temperature. The percentage of ash, fat, protein, and tensile strength of the leather prepared from L. calcarifer skin was significantly highe (P<0.05) compared to leather prepared from T. albacares skin. The percentage of moisture, average thickness, and tear strength of the leather prepared from the T. albacares skin were significantly higher (P<0.05) than the leather prepared from L. calcarifer skin. According to the ΔL*, Δa*, and Δb* values, leather prepared from T. albacares skin has lighter, greener, bluer and L. calcarifer skin has darker, greener, yellower colours respectively. There are no significant colour differences between
prepared leathers (P>0.05). Sensory evaluation results indicated that, finishing, appearance, handling, and overall acceptability, of leather wallet prepared from T. albacares has higher consumer acceptance. The study demonstrated the effectiveness of this novel method for preparation of leather from T. albacares and L. calcarifer skin. In conclusion, T. albacares skin is more suitable
for fish leather preparation using the above described tanning method.
Keywords: Fish leather, Thunnus albacares, Lates calcarifer, Non-Chromium salt tannin, Value
added product
Over 1 million MT of surimi is produced globally, which theoretically would generate approximate 2 million MT of solid by-products and more than 1 million MT of wash water. Utilization of the by-products has increasingly become interested based on their nutritional, economical, and environmental issues. Surimi by-products represent an important source of valuable compounds such as functional protein, collagen, gelatin, fish oil, peptides, minerals, and enzymes. Better utilization of the by-products would make the surimi industry sustainable and profitable. This review paper characterizes sources and composition of the solid by-products and wash water generated from the surimi production as well as factors related to extraction and processing techniques. In addition, the potential food applications are explored including specialty foods and snacks, flavor ingredients, bioactive ingredients, and functional ingredients. Moreover, an outlook summarizing the challenges and prospects on the utilization of surimi by-products is provided.
This study contributes to the fish reverse supply chain due to lack of social-economic and environmental impacts. This study aims to develop a mathematical model for fish reverse supply chain with multi-echelons, multi-products, and multi-periods considering the social-economic (job opportunities and profit) and environmental (carbon emissions) impacts through mixed-integer linear programming (MILP). The proposed model provides social-economic insight for governments to understand the increasing of job opportunities if fish gelatin and powder industries can process fish waste (fish bones and skin). The managerial insight for fish processing industries to increase profit and reduce carbon emission in production, transportation, and warehouse. A sensitivity analysis is illustrated to show that the supply of raw fish, selling prices, and purchasing costs are sensitive to total profit, carbon emissions, and job opportunities. The results show that the total profit for five months is IDR 21,779,378,445 and the largest contribution to the total cost is the costs of purchasing, emission costs, and production costs, which are 44.04%; 23.7%; and 18.2%, respectively.
Biorefineries aim to maximise resource recovery from organic sources that have been traditionally considered wastes. In this respect, leftovers from mollusc and seafood processing industries can be a source of multiple bioproducts such as protein hydrolysates (PH), calcium carbonate and co-composted biochar (COMBI). This study aims to evaluate different scenarios of biorefineries fed by mollusc (MW) and fish wastes (FW) to understand which is the most convenient to maximise their profitability. Results showed that the FW-based biorefinery obtained the highest revenues with respect to the amounts of waste treated, i.e., 955.1 €·t-1 and payback period (2.9 years). However, including MW in the biorefinery showed to increase total income as a higher amount of feedstock could be supplied to the system. The profitability of the biorefineries was mainly dependent on the selling price of hydrolysates (considered as 2 €·kg-1 in this study). However, it also entailed the highest operating costs (72.5-83.8% of total OPEX). This highlights the importance of producing high-quality PH in economic and sustainable way to increase the feasibility of the biorefinery.
Liquid fish fertilizer is a good source of nitrogen, phosphorus and protein, which are essential plant nutrients. hydropriming involves soaking the seeds in water and drying them to improve germination. A percentage of quinoa and cañahua seeds from the Andean Grains Germplasm Bank have low germination, so the objective of the research is to evaluate the effect of hydropriming and liquid trout fertilizer in increasing germination and root growth in quinoa and cañahua seeds. The research was carried out in the laboratory of the Banco de Germoplasma de Granos Andinos, La Paz (Bolivia). A sample of 100 seeds was taken from three accessions of quinoa and cañahua, four treatments were evaluated: control (100%:0%), treatment 1 (99.90%; 0.10%), treatment 2 (99.75%;0.25%), treatment 3 (99.50%;0.50%) and treatment 4 (99.25%;0. 75%) with three replicates, the soaking time was 12 hours at room temperature, then they were dried and arranged in Petri boxes, then introduced into the germination chamber for seven days at a temperature of 17°C, the length of the radicle (mm) was determined by an electronic vernier. The combination of 99.50% distilled water with 0.50% liquid trout fertilizer is the optimum to achieve higher germination percentage and root length in quinoa and cañahua seeds that have low initial germination percentages. The combination of 99.25% distilled water with 0.75% liquid trout fertilizer showed a decrease in both variables, which according to similar research is due to an increase in pH and a decrease in EC. This method can be considered as a strategy to recover seed that registers low germination percentages, besides being economically viable and easily applicable with inputs that are accessible to germplasm banks that have difficulties in periodically refreshing the accessions under their custody.
Expanding sustainable agriculture approaches is critical to increase crop growth and productivity. This farming system should involve organic fertilization and not neglect the recycle of organic waste. One of the organic wastes that can be used as compost is Indigofera tinctoria natural dye waste. The research objective was to examine the vegetative growth response of corn plants to Indigofera tinctoria compost. The design used was a complete randomized block design with one factor of fertilization doses with 3 six levels namely 2.91; 5.83; 8.75; 11.67; 14.58 tons/ha, and chemical fertilizers as controls. Indigofera tinctoria compost meets the standards as organic fertilizer according to the Ministry of Agriculture with characteristics of 18.2% water content, 52.48% organic C, 90.48% organic matter, 2.84% total nitrogen, 1.54% total phosphate, total potassium 2.44%, 1.30% available nitrogen, 0.92% available phosphate, 1.52% available potassium and 60 cmol/kg cation exchange capacity. The dose of compost significantly affected on plant height of 2-4 WAP, stem diameter of 2 WAP , and root biomass of 2 WAP. The compost dose of 5.83 tons/ha has increased root growth and plant height.
Considering the petroleum and fuel prices in India for the past ten years, it can be concluded that there is a huge need for alternative sources of energy. The fuels that are currently used are obtained from fossil fuels, which is on the verge of depletion because of its continuous exploitation. In addition, these fossil fuels emit toxic elements, polluting the atmosphere and causes health ailments, affecting both land and living beings. Production of eco-friendly sources of energy has increasingly gained importance because of the problems involving fossil fuels (nonrenewable sources), such as cost, global warming, and energy crises. Every year, almost millions of tons of lipid-rich fish wastes are dumped by the domestic markets. A part of these wastes is used in the production of animal feed and fertilizers, whereas a majority is discarded in the environment, causing pollution. Recently, research has found out that fish discards are promising alternatives for the production of biogas and biodiesel. This review focusses on the potential benefits of using fish waste in the manufacture of biofuels, as well as the advantages over other methods. In addition, other key factors that play a major role, such as the quality of fish waste that is being dumped, biofuel preparation method, and its utilization, will also be reviewed. Thus, this present study is useful for those who work in industries that process fish, manage fishery waste, and produce biofuel, making it beneficial for them to utilize these high organic wastes in an efficient manner, thereby introducing an alternate renewable biodiesel feedstock.
Biochar made from biomass and biosolids can be used in substrates suitable for urban green infrastructure, especially green roofs, green parking lots, and green walls. The properties of biochar depend on the feedstock and pyrolysis conditions. Biochar made from different feedstocks, e.g., sludges, biomass, food waste, wood, and plant residues, has different physicochemical properties that affect the availability of nutrients, absorption of pollutants and harmful gases, carbon sequestration, and improvement of pH of amended soil. This paper reviews and summarizes various feedstocks for biochar production, pyrolysis technology and conditions, and physicochemical properties of selected types of biochar. Since biochar has a positive influence on plant growth, fertilizer efficiency, and rainwater capture, showing its use as a stable organic component of the substrate is the main objective of this research paper. Conclusion of the review considers the usage of biochar as a substrate for green infrastructure in pursuance of its characteristics, limiting pollutants concentration, potential benefits and risks for the environment, water sources and occurring climate change. The review is based on the analysis of selected papers on existing research and case studies related to the use of biochar and the evaluation of the impact of biochar on the characteristics of growing medium.
With the rise in global population and increased urbanization, the consumption of fish and fish-based by-products gained importance owing to its better and easily digestible protein constituents. Such conditions led to the generation of large amounts of fish waste and pose a detrimental effect to environment. Therefore, the concept of valorization has been introduced in the sector of fish waste management has been introduced which will maintain a cleaner production as well as lead to the production of several value-added products for human well-being. The present research study has pinpointedly discussed several valorization methods like hydrolysis, fermentation, anaerobic treatment, etc. for proper utilization of fish wastes in the manufacturing of fish-based products by pharmaceuticals, nutraceuticals-based industries. Furthermore, for the increase of coastal economy, unprecedented use of different fish growth stimulators and antibiotics are used which unknowingly release antibiotic resistance genes (ARGs) to the environment. Such ARGs lead to the development of ‘resistome’ which will impose a serious threat in the foreseeable future to environmental health. Thus, the concept of waste valorization along with environmental contaminants like ARG will open up a new vista towards proper utilization of fish wastes alongside encouraging entrepreneurs and different government organizations to develop strategies for controlling fish wastes under the circular economy model.
Keywords: Fish waste management; Valorization; Circular bioeconomy; Fish hydrolysate; ARG
India's oldest documented manure, most commonly referred to as Kunapajala, has a long history of over 1,000 years in crop cultivation. Kunapajala is primarily an in-situ decomposition technology of animal waste and can potentially provide an eco-friendly pipeline for recycling bio-waste into essential plant nutrients. This traditional animal manure, in addition, also contains dairy excreta (e.g., feces and urine), dairy products (e.g., milk and ghee), natural resources (e.g., honey), broken seeds or grains, and their non-edible by-product waste. Here, we aimed to assess the waste recycling and plant biostimulant potential of Kunapajala prepared from livestock (e.g., Black Bengal goats) or fish (e.g., Bombay duck) post-processed wastes over different decomposition periods, e.g., (0, 30, 60, and 90-days). In this study, an in-situ quantification of livestock- (lKPJ) and fish-based Kunapajala (fKPJ) reveals a dynamic landscape of essential plant primary nutrients, e.g., (0.70 > NH4-N < 3.40 g•L−1), (100.00 > P2O5 < 620.00 mg•L−1), and (175.00 > K2O < 340.00 mg•L−1), including other physico-chemical attributes of Kunapajala. Using correlation statistics, we find that the plant-available nutrient content of Kunapajala depicts a significant (p < 0.0001) transformation over decomposition along with microbial dynamics, abundance, and diversities, delineating a microbial interface to animal waste decomposition and plant growth promotion. Importantly, this study also reports the indole 3-acetic acid (IAA) content (40.00 > IAA < 135.00 mg•L−1) in Kunapajala. Furthermore, the bacterial screening based on plant growth-promoting traits and their functional analyses elucidate the mechanism of the plant biostimulant potential of Kunapajala. This assay finally reports two best-performing plant growth-promoting bacteria (e.g., Pseudomonas chlororaphis and Bacillus subtilis) by the 16S ribotyping method. In support, in-planta experiments have demonstrated, in detail, the bio-stimulative effects of Kunapajala, including these two bacterial isolates alone or in combination, on seed germination, root-shoot length, and other important agronomic, physio-biochemical traits in rice. Together, our findings establish that Kunapajala can be recommended as a source of plant biostimulant to improve crop quality traits in rice. Overall, this work highlights Kunapajala, for the first time, as a promising low-cost microbial technology that can serve a dual function of animal waste recycling and plant nutrient recovery to promote sustainable intensification in agroecosystems.
Las aguas residuales que provienen de las industrias del enlatado o de las reductoras de pescados, son una fuente rica en una gran variedad de compuestos químicos de interés industrial y de otros altamente perjudiciales para el medio ambiente. Con el fin de reducir el impacto negativo de estos efluentes en los ecosistemas marinos, se han desarrollado diversas técnicas para establecer procedimientos de remoción de los sólidos y recuperación de los nutrientes, como las proteínas para aplicaciones en la industria alimentaria, agroquímica y farmacéutica. Estas proteínas son concentradas mediante una variedad de métodos, siendo el más utilizado la ultrafiltración. Sin embargo, son varias las técnicas de recuperación y modificación de los productos pesqueros que mejoran las cualidades nutricionales, funcionales y biológicas de los concentrados de proteínas en las aguas residuales. En esta revisión, se examinan y se discuten las técnicas no sólo para el tratamiento de los sólidos de las aguas residuales de la industria del enlatado y de la reductora de pescado, sino también de los compuestos químicos presentes y de otros fluidos resultado del procesamiento de los productos de la pesca, con especial mención del uso de la ultrafiltración para la obtención de las proteínas destinadas a las industrias citadas al inicio.
The market demand for marine-based cosmetics has shown a tremendous growth rate in the last decade. Marine resources represent a promising source of novel bioactive compounds for new cosmetic ingredient development. However, concern about sustainability also becomes an issue that should be considered in developing cosmetic ingredients. The fisheries industry (e.g., fishing, farming, and processing) generates large amounts of leftovers containing valuable substances, which are potent sources of cosmeceutical ingredients. Several bioactive substances could be extracted from the marine by-product that can be utilized as a potent ingredient to develop cosmetics products. Those bioactive substances (e.g., collagen from fish waste and chitin from crustacean waste) could be utilized as anti-photoaging, anti-wrinkle, skin barrier, and hair care products. From this perspective, this review aims to approach the potential active ingredients derived from marine by-products for cosmetics and discuss the possible activity of those active ingredients in promoting human beauty. In addition, this review also covers the prospect and challenge of using marine by-products toward the emerging concept of sustainable blue cosmetics.
Fish processing industries generate a large volume of discards. In order to fulfil with the principles of a sustainable circular economy, it is necessary to maintain aquaculture by-products in the food chain through the production of high-value biomolecules that can be used as novel ingredients. In this study, we try to give value to the gilthead sea bream by-products, evaluating the composition and the nutritional value of the muscle and six discards commonly obtained from the fish processing industry (fishbone, gills, guts, heads, liver, and skin), which represent ≈ 61% of the whole fish. Significant differences were detected among muscle and by-products for fatty acid and amino acid profile, as well as mineral content. The discards studied were rich in protein (10%-25%), showing skin and fishbone to have the highest contents. The amino acid profile reflected the high quality of its protein, with 41%-49% being essential amino acids-lysine, leucine, and arginine were the most abundant amino acids. Guts, liver, and skin were the fattiest by-products (25%-35%). High contents of polyunsaturated fatty acids (PUFAs) (31%-34%), n-3 fatty acids (12%-14%), and eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) (6%-8%) characterized these discards. The head displayed by far the highest ash content (9.14%), which was reflected in the mineral content, especially in calcium and phosphorous. These results revealed that gilthead sea bream by-products can be used as source of value-added products such as protein, oils, and mineral supplements.
Increased recycling of nutrient-rich organic waste to meet crop nutrient needs is an essential component of a more sustainable food system. However, agricultural specialization continues to pose a significant challenge to balancing crop nutrient needs and the nutrient supply from animal manure and human excreta locally. For Sweden, this study found that recycling all excreta (in 2007) could meet up to 75% of crop nitrogen and 81% of phosphorus needs, but that this would exceed crop potassium needs by 51%. Recycling excreta within municipalities could meet 63% of crop P nutrient needs, but large regional differences and imbalances need to be corrected to avoid over or under fertilizing. Over 50% of the total nitrogen and phosphorus in excreta is contained in just 40% of municipalities, and those have a surplus of excreta nutrients compared to crop needs. Reallocation of surpluses (nationally optimized for phosphorus) towards deficit municipalities, would cost 192 million USD (for 24 079 km of truck travel). This is 3.7 times more than the total NPK fertilizer value being transported. These results indicate that Sweden could reduce its dependence on synthetic fertilizers through investments in excreta recycling, but this would likely require valuing also other recycling benefits.
Phosphorus (P) is an essential macronutrient in agriculture; however, lack of reporting makes its supply chain a black box. By using literature synthesis on the P challenge, we identify four areas where the reporting process is problematic: P reserves and resources; P losses along the supply chain; P externalities; and access to data. We find that in these areas, the reporting system is inconsistent, inaccurate, incomplete, fragmented and non-transparent. We use systems analysis to discuss implications of reporting on the sustainability of the P supply chain. We find that reporting is essential for the achievement of global P governance and the human right to adequate food. It can also inform decision makers and other impacted stakeholders on policies on agriculture, food security, pollution and international conflict. An improved P reporting process also allows a better evaluation of global sustainability commitments such as the United Nations Sustainable Development Goals.
The aim of this study was to analyze a variety of environmental organic contaminants of emerging concern (CEC) and their metabolites in representative digestate samples from Norwegian biogas production plants. Biogas digestates can be a valuable source for soil amendments and/or fertilizers in commercial agriculture. It is important to assess whether the digestates contain harmful contaminants in order to avoid unintended exposure of human consumers. In total 19 biogas digestates from 12 biogas production plants in Norway were collected and analyzed. Furthermore, process related parameters such as pretreatment of substrates, additives, flocculation and temperature conditions were considered for interpretation of the results. The CEC levels found in the digestates were shown to be dependent on the original composition of the substrate, dry-matter content, and conditioning of the substrate. The sunscreen octocrylene (147 μg L-1) and acetaminophen (paracetamol; 58.6 μg L-1) were found at the highest concentrations in liquid digestates, whereas octocrylene (>600 ng g-1, on a wet weight basis = ww) and the flame retardant TCPP (tris(1-chloro-2-propyl) phosphate, >500 ng g-1 ww) were found at the highest levels in solid digestates, exceeding even the upper limit of quantification (uLOQ) threshold. The highest levels of total CECs were measured in solid digestates (1411 ng g-1 ww) compared to liquid digestates (354 μg L-1 equals 354 ng g-1). The occurrence of CECs in digestate samples, even after extensive and optimized anaerobic digestion, indicates that the operational conditions of the treatment process should be adjusted in order to minimize CEC contamination.
Minimising outputs of waste and pollution by recycling and efficient utilisation of renewable resources is of common interest for organic agriculture and the concepts of circular and bioeconomy. However, in practice, many efforts to increase recycling of various biological materials in organic agriculture are hampered because standards for certified organic production and processing tend to prefer natural products while avoiding processing and especially chemical processes. This creates several dilemmas and weakens the position of organic agriculture as a spear head in the development of a better resource utilisation which will reduce environmental impacts from food production. Based on practical examples derived from projects aimed at better utilisation of residual materials in various food chains, this paper presents some of these dilemmas. Our aim is to initiate a discussion among organic agriculture stakeholders about the regulations for organic production, how they restrict recycling and a better utilisation of valuable resources, and how this can be overcome.
The processing of fish leads to a significant removal of parts of the fish, such as heads, bones, guts, etc., these parts can represent between 30-70% of the fish. The fish silage process transforms fish waste into a liquid mix of hydrolysed proteins, lipids, minerals and other nutrients, easily digestible by both terrestrial and aquatic animals. It can also serve as an excellent fertilizer. Fish silage could make a difference in terms of; i) environmental impact -by reducing levels of waste, ii) animalhealth -by providing nutrients and bioactive components, iii) economic gains -as waste is converted into a valuable product that can replace expensive feed ingredients, or be used as a fertilizer. This manual will provide technical guidance and explain each step and main principles of production and utilization of fish silage.
Anaerobic digestion (AD) from organic waste has gained worldwide attention in reducing greenhouse gas emissions, lowering fossil fuel combustion, and facilitating a sustainable renewable energy supply. Biogas mainly consists of methane (CH4) (50–75%), carbon dioxide (CO2) (25–50%), hydrogen sulphides (H2S), hydrogen (H2), ammonia (NH3) (1–2%) and traces of other gases such as oxygen (O2) and nitrogen (N2). Methane can replace fossil fuels in various applications such as heat and power generation and the transportation sector. The degradation of organic waste through an AD process offers many advantages, such as the decrease of pathogens and prevention of odour release. The digestate from anaerobic fermentation is a valuable fertilizer, however, the amount of organic materials currently available for biogas production is still limited. New substrates, as well as more effective conversion technologies, are needed to grow this industry globally. This paper reviewed the latest trends and progress in biogas production technologies including potential feedstock. Recycling of waste has recently become an important topic and has been explored in this paper.
Os resíduos de peixes em sua maior parte são descartes sem nenhum tratamento prévio, desta forma gerando um sério problema ambiental. Um dos meios de tratamento e aproveitamento desses resíduos seria o método da compostagem, que, por meio da biodegradação, tem como função transformar o resíduo em adubo orgânico. Neste contexto, o presente estudo teve como objetivo avaliar e caracterizar o processo de compostagem de resíduos de peixes oriundos de feiras livres, utilizando como fonte de carbono, maravalha, aparo de grama e poda de árvores. Os parâmetros avaliados foram: temperatura, umidade, potencial hidrogeniônico (pH), cinzas, matéria orgânica total, carbono orgânico total, nitrogênio total, relação C/N e índice de mineralização. Os dados foram submetidos à análise de variância ANOVA e as variáveis que não apresentarão distribuição normal foram analisadas por ANOVA de Kruskall-Wallis e as médias foram comparadas pelo teste de Tukey a 5% significância. Os resultados dos parâmetros físicos- químicos avaliados ao final do processo de compostagem servem para avaliar a eficácia do processo. Assim, observando que o método de compostagem é uma alternativa viável para o aproveitamento de resíduos de peixe, mesmo os resultados do presente estudo tenham apresentado valores para umidade e relação C/N superiores aos recomendados pela legislação brasileira para o uso de fertilizantes orgânicos para ambas os compostos, desta forma, sugerindo o uso de uma maior fonte nitrogênio para a elaboração de compostos orgânicos nas condições experimentais do presente estudo.
Rising environmental concerns on climate changes are causing an increasing attention on reducing wastes dumped to the landfills. As Indonesia's marine fishery industry is in developing stage in its capacity and production systems which consequently increases generation of wastes. Approximately 25-35% of fish production will ultimately become residue or waste due to the unsophisticated technology of fish storage and processing facilities. Most of their wastes dumped in landfills which subsequently impact the environment. Waste minimization program like upcycling waste into the more useful product can be an option for not only dumping wastes dumped into the landfill but also subsequently reducing greenhouse gas emissions such as CO2 and methane. This study evaluated the biological and chemical processes of fish silage production using various additives, including molasses as a carbon source and formic acid. Experiments were conducted in five anaerobic reactors containing 10 kg of fish waste each; the observation period was 40 days. The results indicated that adding molasses (10%, 15%, and 20% in volume) and Lactobacillus plantarum to fish waste significantly influenced pH and water/ash content. On average, the silage process reduced around 38% of fish wastes dumped in a landfill.
In the present study biological method with 15 % molasses and 10% curd were used for preparation of fish silage. The important findings are summarised as: the chemical analysis of fish market waste was observed on wet basis to be moisture 77.09 ± 0.14 %, crude protein 15.20 ± 0.15 %, lipid 4.03 ± 0.07 % and ash 3.30± 0.11 %. Rice bran was used as co-drying material for drying liquid silage. The proximate composition of rice bran contained moisture, crude protein, fat and ash as 9.45 ± 0.19 %, 16.05 ± 0.08 %, 13.42 ± 0.15 % and 10.44 ± 0.14 % respectively on dry weight basis. Powder fish silage was prepared by mixed liquid silage with different quantity of rice bran. For neutralizing the liquid fish silage 1.5% sodium carbonate was added and measured pH value was 6.45. Mixtures were dried within 2-3 days in solar tunnel drier. The proximate composition of powder fish silage made with different quantity of rice bran 10, 20, 30, 40 and 50% contained moisture content as 13.74 ± 0.12, 12.54 ± 0.30, 10.91 ± 0.13, 10.18 ± 0.05, 9.18 ± 0.02 % respectively; crude protein content as 29.50 ± 0.22, 28.56 ± 0.12, 27.66 ± 0.10, 26.53 ± 0.18, 25.73 ± 0.08 % respectively; fat content as 16.28 ± 0.11, 15.71 ± 0.14, 14.45 ± 0.11, 13.73 ± 0.17, 12.60 ± 0.10% respectively; ash content 14.21 ± 0.12, 14.55 ± 0.11, 15.27 ± 0.13, 15.65 ± 0.15, 15.99 ± 0.12 % respectively. Considering all the limitation, powder fish silage with 30 % rice bran was found to be better and carried for further storage study. During storage, moisture content of powder silage was increased in the range from 10.91 ± 0.14 to 11.15 ± 0.10 ,whereas the protein content was decreased in the range from 27.66 ± 0.10 to 27.04 ± 0.06 %, fat content decreased in the range from 14.45 ± 0.11 to 13.42 ± 0.10 %, ash content decreased in the range from 15.27 ± 0.11 to 14.60 ± 0.09 %, Fiber content decreased in the range from 9.89 ± 0.06 to 9.64 ± 0.07 %, Carbohydrate content increased in the range from 21.82 ± 0.07 to 23.14 ± 0.11 %, pH increased in the range from 6.45 ± 0.05 to 6.59 ± 0.14 and TPC increased in the range from 2.10×10 4 to 2.36 ×10 4 cfu/g during the storage period from 0 to 90 days. From above study it can be concluded that fish market waste is suitable for preparation of fish silage powder. At room temperature powder fish silage could be stored up to more than 3 months without loss of major nutrient components.
The manuscript presents results of the evaluation of compost from fish waste (FW) as a fertilizer for agricultural use. A pot experiment was conducted to compare the effects of compost from FW on the yield and macro and microelemental composition of ice lettuce (Lactuca sativa L.). In addition, the phytotoxicity degree of the compost and compost effects on seed germination and primary root growth were determined with white mustard (Sinapis alba L.). Compost used in the study consisted of FW and pine bark. Results of the evaluation enable concluding that the compost from FW is non-phytotoxic, mature, stable, and suitable for use in agriculture. Its addition to soil caused an increase in fresh and dry matter yield of leaves of ice lettuce (L. sativa L.). Fertilization had a significant effect on increased contents of nitrogen, phosphorus, potassium, sodium, calcium, and magnesium in leaves of the test plant. The average accumulation of microelements in ice lettuce (L. sativa L.) grown in the soil fertilized with compost from FW followed the descending order Fe > Cu > Ni > Zn > Mn, respectively. Soil fertilization with compost from FW improved the K:(Mg + Ca), K:Mg and K:Ca ratios but, simultaneously, deteriorated the Ca:P ratio.
Graphical Abstract
This trial evaluated the composting for valuation of marine fish waste. The study was carried out in a composting cell (1.10m length, 1.50m width, 1.20m height, and 2.50m headroom), which received a mixture of marine fish waste (skin and fin) and reused wood shavings at a 7:3 proportion. The efficiency of the composting process was evaluated through analysis of biomass temperature, moisture, pH, ash, compost mineralization index, carbon/nitrogen ratio, total organic matter, total organic carbon and total nitrogen. Data were tested by analysis of variance and polynomial regression, and the means compared by Tukey's test at 5%. The results showed that composting is an efficient alternative for the valuation of fish residues. The compost complies with the Brazilian Standards (Normative Instruction 25/2009 of the Brazilian Ministry of Agriculture, Livestock and Food Supply). The C/N ratio lower than 15/1 combined with the high moisture content of the substrates inhibit the increase in the biomass temperature. The wood shavings reused for three consecutive times provide nitrogen. The addition of water to the composting process should be suppressed when using the proportion of 7kg fish waste and 3kg reused wood shavings.
In the present study an attempt was made for transformation of fish market waste into silage by using three different methods: Inorganic (98% sulphuric acid with weight percentage of 2.5, 3.5 and 4.5%), organic (98% formic acid with weight percentage of 2.5, 3.5 and 4.5%) and biological method (molasses with weight percentage of 5, 10, 15% and curd used as lactic acid bacteria source for fermentation). The chemical, microbiological and nutritional properties of the differently preserved fish silages were estimated during a storage period of 60 days at ambient temperature. The important findings are summarised as the rate of pH, AAN and TVB-N values were gradually increased and then get stable. In case of biological silage 10% and 15 % molasses pH was decreased below 4.5 after 72 hours. The rate of autolysis in sulphuric acid silage was slow compared to formic acid and biological silage. In case of bio-fermented silage (15% molasses) a steady supply of nutrients from molasses showed a steady increase in LAB from 2.24×106 to 3.67×109cfu/g and then decrease. TPC was decreased from 4.50×106 to 8.20×103cfu/g. In present study, sulphuric acid 2.5%, formic acid 2.5%, biological silage 5 and 10% silages were corrupted at the end of 24, 24, 12 and 30 days respectively. The appropriate amount of sulphuric acid, formic acid and molasses for preparation of fish silage were determined as 3.5%, 3.5% and 15% respectively.
Waste from the beneficiation of fish was composted with crushed grass aiming to characterize their chemical composition and investigate the possibility of the use of the final compost as source of humic acids (HA) able to stimulate the growth of lettuce. Compost presented pH value, C/N ratio, and electrical conductivity that allow its use as an organic fertilizer. The element content was present in the following order of abundance in the compost: P > Ca > N > Mg > K > Fe > Zn > Mn > Mo > Cu, and the humus composition was similar to that observed in others kind of organic residues composted. The high content of oxygen pointed out a high level of oxidation of HA, in line with the predominance of phenolic acidity in the functional groups. The ¹³C-NMR spectra showed marked resonances due to the presence of lipids and other materials resistant to degradation as methoxy substituent and N-alkyl groups. A concentration of 20 mg L⁻¹ HA increased significantly both dry and wet root matter in lettuce but the CO2 assimilation, stomatal conductance, and number of lateral roots of the plants were not affected. However, increases of 64% in the water-use efficiency was observed due to the HA addition, probably related to the root morphology alteration which resulted in 1.6-fold increase of lateral root average length and due to the higher H⁺ extrusion activity. Reuse of residues from the fish beneficiation activity by composting may represent a safe tool to increase the value of recycled organic residues and generate HA with potential use as plant growth stimulants.
Protein hydrolysates (PHs) are an important group of plant biostimulants that have received increasing attention in recent years because of their positive effects on crop performance and contribution to agroecological sustainability. The aim of the study was to determine the effects of fish-derived PHs on growth, chlorophyll content and fluorescence, and leaf gas exchange of lettuce (Lactuca sativa) grown in a growth chamber. Fish-derived PHs were drench applied (300mL of 3 mL·LL⁻¹) three times at 0, 14, and 24 days after transplanting (DAT), and lettuce were evaluated 30 DAT. Application of PHs significantly increased the lettuce leaf number per plant from 22 to 28, stem diameter from 1.37 to 1.68 cm, shoot fresh and dry weight (FW and DW) from 59 to 89 g and 5.5 to 7.7 g, and root dry weight from 0.52 to 0.80 g. It also significantly increased the leaf relative water content (RWC) from 87% to 90% and succulence from 267 to 288 g·mL⁻² water, but had no effect on specific leaf area (SLA). PHs significantly enhanced chlorophyll content, photosynthetic rate, stomatal conductance, and transpiration rate although they did not alter chlorophyll fluorescence. Our study indicated that plant biostimulants and fertilizer PHs improved plant performance and might have potential to be used for sustainable production of lettuce. © 2017, American Society for Horticultural Science. All rights reserved.
Fertilizer is a critical input for improving production and increasing crop yields. The effect of chemical fertilizer, fish offal's fertilizer and manure on marketable yield and other parameter of tomato (Lycopersicon esculentum) and Adama red onion (Allium cepa) were compared. The experiment was laid as a randomized complete block design (RCBD), with three treatments; chemical fertilizer (T 1), fish offal's fertilizer (T 2) and manure (T 3). Treatments encompassed 0.24 kg diammonium phosphate (DAP) of chemical fertilizer, 2 kg of ground fish offal's fertilizer and 10 kg of unfermented (fresh) manure for tomato. Similarly, 0.12 kg DAP of chemical fertilizer, 1 kg of ground fish offal's fertilizer and 5 kg of unfermented manure for Adama red onion. 3 × 4 m plot size was used for tomato and 2 × 3 m plot size was used for Adama red onion. The results indicated that there is significant difference (p < 0.05) in tomato height at first harvesting with the maximum height of 80.33 ± 3.97 cm from plot treated with fish offal's fertilizer. There is significant difference (p < 0.05) in onion bulb weight. The maximum bulb weight was 112.51±16.4 g recorded from plot treated with chemical fertilizer. Tomato fertilized with fish offal's fertilizer grew better than those fertilized with chemical fertilizer at later stages. Fish offal's fertilizer boosted the production at the later age and concluded that it can be used as an alternative to chemical fertilizer for tomato. The use of fish offal's fertilizer for different crops, application time and amounts should be further studied.
The idea of a circular economy (CE) has become prominent in both European and Chinese policy making. Chinese and European perspectives on a CE share a common conceptual basis and exhibit many similar concerns in seeking to enhance resource efficiency. Yet they also differ, and this article explores differences in the focus of CE policy in China and Europe. We present evidence on the differing understandings of the CE concept in Chinese and European policy discourse, drawing on qualitative and quantitative analysis of policy documents, media articles, and academic publications. We show that the Chinese perspective on the CE is broad, incorporating pollution and other issues alongside waste and resource concerns, and it is framed as a response to the environmental challenges created by rapid growth and industrialization. In contrast, Europe's conception of the CE has a narrower environmental scope, focusing more narrowly on waste and resources and opportunities for business. We then examine similarities and differences in the focus of policy activity in the two regions and in the indicators used to measure progress. We show differences in the treatment of issues of scale and place and different priorities across value chains (from design to manufacture, consumption, and waste management). We suggest some reasons for the divergent policy articulation of the CE concept and suggest lessons that each region can learn from the other.
This paper presents the possibility of producing phosphorus fertilizers through Acidithiobacillus ferrooxidans utilization in secondary raw materials solubilization. Phosphorus was obtained from the bones of poultry and fish as well as from Morocco phosphorite. Four doses of poultry bones and fish bones were used in the experiment (2, 4, 10 and 20 g/L) and two doses (2 and 4 g/L) of phosphorite were also used. The experimenters measured the final pH, which increased in proportion to the increase in the number of poultry bone doses, whereas in the case of fish bones it decreased in proportion to the increase in the number of fish bone doses. Only in the case of phosphorite, where 10 g/L were used, there was a slight increase in pH during solubilization observed. The highest phosphorus concentration of 1.9% (expressed as P2O5) was found for the solubilization performed on fish bones with the highest dose (20 g/L). The formulation obtained in this study meets the necessary requirements for use as a bio-fertilizer because of the relatively low content of P2O5 and the low content of toxic elements. The results confirm the utilization of Acidithiobacillus ferrooxidans in the biosolubilization of phosphorus renewable raw materials that can alleviate the problem of the world's depleting phosphorite deposits.
The feasibility of using enzyme activities for indicating the state of marine fish waste composting was examined in this study and the evolution of the composting process for a 60 days period was evaluated. Results indicated that stable and mature fish waste compost has been generated. During the composting process, oxidoreductase enzyme (dehydrogenase) and hydrolase enzyme (β-glucosidase and phosphatase) activities decreased with time since available organic compounds decreased. A good correlation among enzyme activities and different physiochemical parameters including oxygen uptake rate (OUR), carbon/nitrogen (C/N) ratio, and germination index (GI) led to the conclusion that both hydrolytic and dehydrogenase enzyme activities could be feasible indicators of the state and evolution of the composting process.
The soil fertility largely depends on the nature
and the quantity of trace elements. Application of chemical
fertilizers to increase the food production slowly robs the soil
nutrients, harm the soil fauna and microbes and cause side
effects to consumers. Gunapaselam is prepared from fish
waste by fermentation. The aim of the present study is to
assess the level of trace elements, microbial population and
the growth characteristics of Vigna radiata, green gram after
applying Gunapaselam. The soil was amended with either
chemical fertilizer (25kg N2: 50kg P2O5: 25kg K2O: 20kg
S/ha) or Gunapaselam (1:100 diluted) on alternative days.
The soil was analyzed for trace elements Iron (Fe), Copper
(Cu), Zinc (Zn), Manganese (Mn), Boron (B), Nickel (Ni)
before and after applying Gunapaselam. Amendment of
Gunapaselam to soil has improved the quantity of trace
elements, macro nutrients and plant growth promoting
microbial status of soil. Spearman rank correlation test
reveals positive correlation with the growth traits and
formation of number of nodules. The results suggested that
the addition of Gunapaselam may be considered as a novel
liquid biofertilizer as it promotes growth and increase
nodulation probably by enriching the soil with trace elements
and microbial community.
This study was carried out to evaluate the effect of Gunapaselam – fermented fish waste, on the growth of Solanum
melongena (Brinjal) plants. Gunapaselam was prepared by fermenting the fish wastes like head, gut, fins, bones
etc., with Jaggery. After 15 days, the fermented liquid fish waste was filtered and used as liquid manure. Brinjal
seeds were sown in different pots with only water (control), Urea (reference) and Gunapaselam (test). Application
of Gunapaselam decreased the soil pH and enhanced the exchangeable cation levels, organic matter and the
essential plant nutrients nitrogen, phosphorus and potassium. Improvement in the growth traits of brinjal plants like
leaf area, plant height, stem diameter, root length, fresh plant weight were observed when compared with water
control and urea fertilized treatment groups. These results were in synchronization with the anatomical results of
root and stem. The thickness of the conducting systems, phloem and xylem were increased which facilitates the
translocation, conductance and storage of photosynthates. The results indicated that Gunapaselam is a valuable
resource for enhancing the soil fertility and growth of plants like brinjal. This study indicated the potential for the
reclamation of fish waste as a useful liquid fertilizer for agricultural purposes.
Fish soluble nutrients (FSN) applied at weekly or biweekly intervals gave comparable growth and fruit yield of greenhouse-grown tomatoes ( Lycopersicon esculentwn mill.) as plants fertilized with full strength Hoagland’s nutrient solution. FSN fertilization stimulated vegetative growth and delayed flowering and fruit-ripening by 5-8 days depending upon concentration and frequency of application. FSN can be a useful nutrient source for crop fertilization.
Fish waste, seaweed and pine bark were composted to obtain a stable product rich in organic matter and nutrients for use in organic agriculture. The compost was assessed as an organic fertilizer for potato crops. The influence of three different compost rates (viz., C1 = 32 t ha⁻¹, C2 = 43 t ha⁻¹ and C3 = 65 t ha⁻¹) on potato production and the chemical composition of potato tuber, petiole and foliole was compared with that of a mineral fertilizer (M), a certified organic fertilizer consisting of dehydrated broiler litter (BL) and a control treatment involving no fertilizer (C). The compost exhibited a substantial fertilizing effect and even surpassed the mineral fertilizer in this respect. The C3 treatment increased total production by 53 and 30% relative to C and M, respectively, and was similar to BL in this respect; also, it considerably reduced non-commercial production (calibre <35 mm according to Spanish regulation RD 31/2009) relative to C. Only the C3 treatment altered the chemical composition of the tubers (specifically, it increased the content in reducing sugars). Therefore, the compost is useful as a fertilizer for organic potato crops.
Fish waste biomasses are locally available resources which contain nutrients. Fermentation of the biomass produces slurries used for plankton production and plant/agri-nutri use. Bio-refinery of fish waste material can be converted into value added biological products such as biofuels, industrial chemicals, animal and fish feed, human food, neutraceuticals and organic fertilizer, etc. Fish processing waste could be regarded as a promising renewable biomass resource for bio-refineries. Hydrolysis of fish waste is aimed primarily at industrial applications of the process. Low cost and simplicity of operation by reducing the cost of material, energy consumption and labour, but maintaining high productivity are some of the important attributes at the industrial application process. Fish hydrolysate generally shows a beneficial effect on growth performances and feed utilization at low inclusion levels. The performance is postulated to be due to the balance of free amino acids, peptides and proteins in digestion, absorption and utilization.
Bioactivities of bulk fish protein hydrolysates (FPH) from defatted salmon by-products obtained with eight different commercially enzymes and their combinations were tested. All FPH showed antioxidative activity in vitro. DPPH scavenging activity increased, while iron chelating ability decreased with increasing time of hydrolysis. All FPH showed ACE inhibiting effect which depended on type of enzyme and increased with time of hydrolysis. The highest effect was found for FPH produced with Trypsin. Bromelain + Papain hydrolysates reduced the uptake of radiolabelled glucose into CaCo-2 cells, a model of human enterocytes, indicating a potential antidiabetic effect of FPH. FPH obtained by Trypsin, Bromelain + Papain and Protamex showed the highest ACE inhibitory, cellular glucose transporter (GLUT/SGLT) inhibitory and in vitro antioxidative activities, respectively. Correlation was observed between the measured bioactivities, degree of hydrolysis and molecular weight profiles, supporting prolonged hydrolysis to obtain high bioactivities.