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Eliminating turbidity in drinking water using the mucilage of a common cactus

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Eliminating turbidity in drinking water using the mucilage of a common cactus

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Abstract

Diced Nopal cladodes (pads) have been used for the treatment of turbid natural spring waters in Latin America. To investigate this phenomenon, the mucilage derived from the species Opuntia ficusindica was investigated. Comparison against the commonly used synthetic flocculent, aluminium sulfate (Al-2(SO4)(3)) demonstrated the high efficiency of the cactus to eliminate turbidity. The mucilage extract increased particulate settling rates 330% compared with aluminium sulfate, at dosage concentrations of 3 mg L-1, while its performance was equivalent at doses 0.3% of the required Al-2(SO4)(3) concentration. The cactus mucilage, which consists of complex carbohydrates and sugars, has unique surface activity characteristics that make it an ideal candidate for enhancing dispersion properties, creating emulsifications, and for reducing the surface tension of high polarity liquids. These results indicated that the Nopal cactus mucilage has the potential to be the basis for a new 'green' technology, which is environmentally benign and cost-effective.

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... Coagulation is a critical step in water treatment processes, not only because it removes particles but because it also removes the microorganisms that are often attached to the particles (Miller et al. 2008;Zand et al. 2011). Under conditions normally encountered in settling basins, effluent removal of particles less than (50 lm) in diameter cannot be expected without coagulation (Peavy et al. 1986). ...
... Opuntia spp., commonly called ''nopal'' in Mexico, prickly pear or cactus leaf in USA, grows readily in Mexico, Texas, and other arid and semiarid regions. It is commonly eaten and is used for medicinal purposes (Mondragon-Jacobo et al. 2001;Nobel 2002;Miller et al. 2008;Torres et al. 2012;Pichler et al. 2012). It also grows abundantly in Iraq where this research has been conducted. ...
... As shown in Fig. 2, it is clear that particles with a size of B50 lm or B0.05 mm represent 72 % of the raw water turbidity sample so that as described in Introduction, these particles required coagulation before passing to the settling basin (Peavy et al. 1986). ...
Article
A comparative study was performed between cactus (Opuntia spp.) and alum as coagulants. Monthly samples of raw water, delivered from (Al-Mashroo Canal), were studied and analyzed for turbidity removal during the period from August 29, 2014, to July 23, 2015. The analysis was conducted to decide the optimum dose, optimum velocity gradient, and optimum flocculation time for both coagulants. The results of the study indicate the efficiency of alum over cactus and that the optimum dose of alum was larger than that of cactus. The pH level of raw water was in the range of 7.734–8.203, while the temperature of raw water was in the range of 13–35 °C during the period of the study. The reliable velocity gradient for both coagulants was 25 1/s, and the reliable flocculation time for both coagulants was 20 min. The residual turbidity for cactus was in the range of 0.0–296 NTU, while that of alum was in the range of 0.0–5.81 NTU.
... Historiquement, coagulants naturels et bio-flocculants à base de plantes ont été utilisés dans le traitement des eaux potables et des eaux usées avant l'avènement des produits chimiques synthétiques (Pichler et al., 2012). Mais leur utilisation a été déconseillée dans les pays développés sous prétexte qu'ils n'ont jamais été soumis à une évaluation scientifique rigoureuse (Pichler et al., 2012 ;Theodoro et al., 2013). ...
... Historiquement, coagulants naturels et bio-flocculants à base de plantes ont été utilisés dans le traitement des eaux potables et des eaux usées avant l'avènement des produits chimiques synthétiques (Pichler et al., 2012). Mais leur utilisation a été déconseillée dans les pays développés sous prétexte qu'ils n'ont jamais été soumis à une évaluation scientifique rigoureuse (Pichler et al., 2012 ;Theodoro et al., 2013). Récemment, il y a eu plus d'intérêt pour les produits naturels. ...
... L'eau séparée de la boue par décantation constitue l'eau épurée. (Vijayaraghavan et al., 2011 ;Pichler et al., 2012 ;Kazi et Virupakshi, 2013 ;Belbahloul et al., 2014 ;Al-Saati et al., 2016 ;Rebah et Siddeeg, 2017;Bouaouine et al., 2017). Des rabattements de la turbidité, des MES, de la demande chimique en oxygène (DCO) et des éléments métalliques, etc. ont été observés au cours de ces études (Figs. ...
Thesis
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Contamination des sols et des sédiments de surface par les éléments traces métalliques et leurs traitements dans les effluents domestiques et industriels par l’usage des bio-floculants dans la région de Gafsa-Métlaoui
... Aloe vera merupakan tanaman yang termasuk golongan Liliaceae (Pichler et al., 2012). Biasanya, Aloe vera digunakan sebagai penyubur rambut, penyembuh luka, perawatan kulit, serta bahan makanan dan minuman kesehatan. ...
... Biasanya, Aloe vera digunakan sebagai penyubur rambut, penyembuh luka, perawatan kulit, serta bahan makanan dan minuman kesehatan. Kemampuan Aloe vera sebagai koagulan karena mengandung karbohidrat kompleks dan gula yang dapat mengikat partikel-partikel di dalam air (Maharani et al., 2020;Musriyah, 2016), juga mengandung mucilage atau gel seperti pada tumbuhan kaktus yang dapat digunakan sebagai penjernih air (Mujariah et al., 2016;Permatasari, 2013;Pichler et al., 2012;Pranata et al., 2019;Puspitasari et al., 2013). ...
... Hasil penelitian ini mengonfirmasi penelitian (Mujariah et al., 2016) yang menyatakan bahwa Aloe vera dapat digunakan sebagai koagulan alami. Aloe vera termasuk dalam golongan Liliaceae (Pichler et al., 2012). Biasanya, Aloe vera digunakan sebagai penyubur rambut, penyembuh luka, perawatan kulit, serta bahan makanan dan minuman kesehatan. ...
Article
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Dug wells are the most widely used clean water facilities in the community, but they often have high turbidity levels. So that processing must be done using a coagulant material. Aloe vera is a natural ingredient that contains complex carbohydrates, sugars, and mucilages which can bind particles in water. This study aims to determine the effect of variations in Aloe vera doses on reducing water turbidity. This study used a completely randomized design (CRD) with three dose variations (0.1 ml, 0.2 ml, and 0.3 ml) and six repetitions. A total of 500 ml of raw water from resident wells was used for each treatment. The results showed that at a dose of 0.1 ml, the turbidity decreased by 3.7%, from 41.1 NTU to 39.6 NTU (SD = 0.54). The dose was 0.2 ml, decreased by 6.8% (38.3 NTU; SD = 1.54), and the dose was 0.3 ml decreased by 13.9% (35.4 NTU; SD = 1.02). Statistically, it showed a significant difference in turbidity in each treatment group (p-value <0.05). Research has shown that Aloe vera can be used as a natural coagulant, but further research is needed to determine the correct dosage.
... Mucilage is a complex polymeric substance composed mainly of carbohydrates with highly branched structures, which include l-arabinose, d-galactose, l-rhamnose, dxylose, and galacturonic acid in various proportions [8]. It also contains glycoproteins [9] and other substances such as tannins, alkaloids, and steroids [1]. The mucilage composition differs among the various Opuntia spp. ...
... In addition to the aforementioned medicinal activities for these cacti, which are associated with this complex material, the ability of mucilage to form molecular networks and retain large amounts of water makes it a potential source of hydrocolloids for the chemical and cosmetics industries. Several studies have evaluated its uses in water purification/filtration [2,9], as an adhesive lime [Ca(OH) 2 ] [3], emulsifying agent [10], or flocculant [11], and as an enhancer of water infiltration in soils, due to its physical properties (viscosity, elasticity, texture, and emulsifier) [12]. Other mucilage applications include its use in foods as a stabilizer, flavoring agent, fat substitute [2], and edible coating to extend the useful life of fruit [13]. ...
... Mucilage has the potential to be used in the clarification of water due to its ability to retain different types of particles that are dispersed therein [9]. Additionally, as a negatively charged polyelectrolytic molecule due mainly to its sugar composition, mucilage has the ability to attract or retain certain types of positively charged substances. ...
Article
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The aim of this study was to extract mucilage from O. cochenillifera (L.) cacti and determine its functional and physicochemical properties. The best mucilage yield (31%) was obtained by nonthermal extraction with hydration. The mucilage has appreciable carbohydrate and protein contents. The phytochemical analysis shown the presence of alkaloids and terpenes/steroids. The Fourier transformed infrared (FT-IR) spectrum of the mucilage exhibits typical bands for carbohydrates as O–H, C–H, and –COO ⁻ . The mucilage demonstrated water- and oil-holding capacities of 2.78 g water/g dry mucilage and 1.80 g oil/g dry mucilage, respectively, these properties can have a positive effect on the texture of the products when used as a stabilizer. The mildly acidic pH (4.8–5) contributes to its emulsifying capacity. The presence of electrolytes in the mucilage can be of great value in flocculation processes. The mucilage forms low viscosity solutions in the same manner as gum Arabic. Finally, its potential for use as a textile dye remover was evaluated, achieving a 70% removal rate from aqueous solutions. The prepared mucilage exhibits properties that recommend it as a natural material that can be used as an additive in the chemical, food, pharmaceuticals and cosmetics industries, as well as in decontamination processes.
... El nopal tunero (Opuntia spp.) es una planta xerófita cultivada en regiones áridas y semi-áridas marginales de México y en agro-ecosistemas similares del mundo. Esta planta ha sido usada para solucionar problemas de erosión del suelo, como alimento para ganado en épocas de sequía hídrica, usos industriales y para consumo humano como hortaliza y fruta (Barros y Buenrostro, 1998;Nobel, 1998;Nefzaoui y Ben Salem, 2002;Pichler et al., 2012). Como fruto, al igual que en otros cultivos frutales, el nopal tunero requiere de prácticas agrícolas para optimizar tanto la producción como mejorar la calidad del fruto. ...
... The prickly pear (Opuntia spp.) is a xerophytic plant cultivated on marginal arid and semi-arid regions of Mexico and similar agro-ecosystems in the world. This plant has been used to solve problems of soil erosion, livestock feed in times of drought, industrial use and human consumption as a vegetable and fruit (Barros and Buenrostro, 1998;Nobel, 1998;Nefzaoui and Ben Salem, 2002;Pichler et al., 2012). As a result, as in other fruit crops, prickly pear farming practices required to optimize both production and improve fruit quality. ...
Article
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Irrigation in the quality and shelf-life of tuna has not been documented so far. The objective of this research was to study the influence of irrigation on quality, shelf-life and packaging of tuna 'Cristalina' and 'Amarilla Olorosa' after a cooling period. The fruits were harvested from the following irrigation treatments: no irrigation (NI) as control, supplementary irrigation (SI) and full irrigation (FI). Three batches of 72 fruit (24 fruits per treatment), each made to evaluate its quality at harvest and after storage at room temperature (SRT) and cooling over seven days in room conditioning (R+RT). At harvest, the fruit weight (FW) of 'Cristalina' was lower in NI plants than SI or FI. The firmness (F), the concentration of total soluble solids (CSS) and fruit dry matter (DM) were similar between the treatments. After SRT or R+RT, the FI held high the FW and F, but reduced the DM. In both storage systems, loss of fruit weight was lower in the FI or SI. The tuna 'Amarilla Olorosa' behaved like 'Cristalina' and had no damage by fungi or cold. Compared to the FI, SI induced similar responses in both types of tuna and saved ≈56% of irrigation water; therefore, this irrigation strategy could be suggested for this and similar agro-ecological areas.
... It is a succulent climbing shrub with red flesh and red peels, growing on long, thin, vining cactuses. Hylocereus species are known to have coagulant characteristics as their peels have already been proven to be efficient in removing dyes and toxic metal ions from water (Mallampati, Xuanjun, Adin, & Valiyaveetil, 2015), the mucilage in their stem demonstrated high efficiency in reducing turbidity (Pichler, Young, & Alcantar, 2012), and their foliage have also been studied as a plant-based coagulant for treatment of palm oil mill effluent, wherein it proved to be effective at removal of the percentage of chemical oxygen demand, suspended solids, and turbidity of the said effluent (Som & Wahab, 2018). ...
... Mucilage and complex carbohydrate content in Hylocereus species stem and its associated water retention capacity is also said to be behind its coagulant properties (Saenz, Sepulveda, & Matsuhiro, 2004). This mucilage even demonstrated high efficiency in reducing turbidity as compared to aluminum sulfate [Al 2 (SO 4 ) 3 ], a standard water coagulant (Pichler, Young, & Alcantar, 2012). Hylocereus species foliage have also been studied as a plant-based coagulant for treatment of palm oil mill effluent, a pollutant waste from the palm oil industry, wherein it proved to be effective at removal of the percentage of chemical oxygen demand, suspended solids, and turbidity of the said effluent (Som & Wahab, 2018). ...
Preprint
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This study is focused on the effectiveness of Hylocereus polyzhirus peels, foliage, and flesh as natural coagulants on polluted river water. Coagulants are a vital process of water treatment whereas it is used to remove the turbidity in raw water. The experiment conducted standard jar tests with the extracted phytochemicals from the H. polyzhirus and the river water while using a magnetic stirrer. The three parts of the said fruit, namely the peels, foliage, and flesh are extracted independently of their phytochemicals. Three sets of three beakers of 100 mL river water are added with the phytochemical extracted respectively from each part. The amount of dosage for the water treatment is set uniform at 50 mg/L. In determining the results of the treatment, the water is tested in three water parameters which is through the measurement of turbidity in water transparency and total suspended solids, measurement of pH level, and measurement of conductivity.
... Due to the existence of water band interference in conventional infrared spectroscopy, Pichler et al. (2012) used Raman Spectroscopy to characterize the OFI mucilage. The mucilage's Raman spectrum had a broad peak in the 3600e3200 cm À1 due to OH, 1730, 1630 and 1610, 1414 cm À1 due to C]O, HeOeH, C]C and eCH 2 vibrations respectively with peaks in the 800 cm À1 suggesting liberation mode of residual water molecules. ...
... In a similar study, Pichler et al. (2012) investigated the possibility of eliminating turbidity in drinking water using the gelling extract (GE), non-gelling extract (NE) and the combined extract CE (GE þ NE) from OFI in comparison to alum, Al 2 (SO 4 ) 3 . Standard cylinder tests performed with 5 g/L of neutral kaolin slurries exposed to flocculant dosages of 3 mg/L showed that GE had far pleasing floc settling rate of 2.2 cm/min compared to those of Alum (0.67 cm/min), NE (À0.7 cm/min) and CE (À1.1 cm/min). ...
... Mucilage is a complex polymeric substance composed mainly of carbohydrates with highly branched structures, which include L-arabinose, Dgalactose, L-rhamnose, D-xylose and galacturonic acid in various proportions [3]. It also contains glycoproteins [4] and other substances such as tannins, alkaloids and steroids [5]. Parkia biglobosa (Mimosoideae -Leguminosae) commonly called the African locust bean tree has long been widely recognized as an important indigenous fruit tree in anglophone and francophone West Africa. ...
... The powder was then dispersed in 8.5 mL of distilled water and the volume made up to10 mL with more water. After 24 h of standing, the volume of the sediment, V2, was estimated and the swelling capacity was computed using Equation 4. ...
Article
Full-text available
Parkia biglobosa gum and mucilage are versatile plant products which are mostly used in food as well as in pharmaceutical industries and can easily be carboxymethylated to modify their physicochemical characteristics. This work aimed to evaluate the physiochemical and rheological properties of the mucilage from Parkia biglobosa seeds. The mucilage was extracted from Parkia biglobosa seeds and modified by carboxymethylation via the Williamson´s synthesis using monochloroacetic acid as the etherifying agent. Physico-chemical characeterization was carried out on the modified mucilage via viscosity and swelling capacity investigation and for its degree of substitution via titrimetric, Fourier transform infra-red spectroscopy (FT-IR) and differential scanning calorimetry (DSC) techniques. Hydration capacity, moisture sorption, scanning electron microscopy, rheological and flow properties were used to characterize the mucilage. Both mucilages had desirable pleasant odours and bland taste. The extracted mucilage produced a derivative with higher hydration and moisture sorption capacity, a marked decrease in viscosity, and improved flow properties. Also, changes attributable to modification were observed from the FT-IR spectra and DSC thermograms. Both the extracted and modified mucilage possessed fundamental characteristics that would make them suitable as pharmaceutical excipients in the formulation of solid and liquid dosage forms.
... In general, mucilage is a complex polymeric substance composed mainly of carbohydrates [4]. It also contains glycoproteins [5] and other substances such as tannins, alkaloids, and steroids [6]. Mucilages have rheological properties that are of great interest for a wide range of thickening agents for the food and pharmaceutical industries [7], [8], [9]. ...
... The ability of mucilage to form molecular networks and retain large amounts of water makes it a potential source of hydrocolloids for the chemical and cosmetics industries. Several studies have evaluated its uses in water purification/filtration [5], [16], as an adhesive lime [Ca(OH) 2 ] [17], emulsifying agent [18], or flocculent [19], and as an enhancer of water infiltration in soils, due to its physical properties (viscosity, elasticity, texture, and emulsifier) [20]. Other mucilage applications include its use in foods as a stabilizer, flavoring agent, fat substitute [16]. ...
Article
Full-text available
Cereus triangularis is a cactus belonging to the sub-family of Cactoideae. Its cladodes are used in food decoction as a traditional medicine in Madagascar. The chemical structure of polysaccharide extracted from its cladodes is a type I arabinogalactan with a high molecular weight.In this study we have investigated its physicochemical properties, the rheological properties and prebiotic property of the oligo-or polysaccharides cladodes of Cereus triangularis. The rheological properties of this galactan are characteristic of a pseudoplastic fluid with a weak gel behavior. Storage modulus (G′) and loss modulus (G″) of the polysaccharide in 0.5 M NaCl and KCl 0.5 M revealed the viscoelastic properties.Its enzymatic degradation using a fungal galactanase led to the production of oligomers and low molecular weight polysaccharides which have been successfully tested as prebiotics.
... Its flocculation capacity was such that water with a turbidity of 12 NTU required 3.5 ml to bring it to a clarity level of 4.36 NTU in less than 30 min. This value is within the recommended level by the WHO (Pichler et al. 2012). ...
Article
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This is a report on comprehensive characterization of cadmium (Cd)-exposed root proteomes in tomato using label-free quantitative proteomic approach. Two genotypes differing in Cd tolerance, Pusa Ruby (Cd-tolerant) and Calabash Rouge (Cd-sensitive), were exposed during 4 days to assess the Cd-induced effects on root proteome. The overall changes in both genotypes in terms of differentially accumulated proteins (DAPs) were mainly associated to cell wall, redox, and stress responses. The proteome of the sensitive genotype was more responsive to Cd excess, once it presented higher number of DAPs. Contrasting protein accumulation in cellular component was observed: Cd-sensitive enhanced intracellular components, while the Cd-tolerant increased proteins of extracellular and envelope regions. Protective and regulatory mechanisms were different between genotypes, once the tolerant showed alterations of various protein groups that lead to a more efficient system to cope with Cd challenge. These findings could shed some light on the molecular basis underlying the Cd stress response in tomato, providing fundamental insights for the development of Cd-safe cultivars. Graphical abstract
... Con este estudio, se reafirma las bondades del mucílago de las plantas Cactaceae como agente coagulante en el proceso de clarificación de agua, tal como lo sugieren otros investigadores [16][17][18][19][20][21]. ...
Article
Full-text available
En la clarificación del agua potable se utilizan productos químicos como el sulfato de aluminio para remover materia coloidal y sustancias orgánicas, mejorando la calidad del agua. Elevadas concentraciones de aluminio residual en el agua potable tienen implicaciones en la salud humana, siendo necesario el desarrollo de coagulantes alternativos, ambientalmente aceptables para reemplazarlos. En esta investigación se evaluaron las propiedades que tiene la tuna opuntia ficus-indica y el alumbre en la clarificación de las aguas del río Magdalena en Magangué, Departamento de Bolívar (Colombia); como coagulante. Finalmente, se demostró la eficiencia que tiene el mucilago extraído de la tuna opuntia ficus-indica como coagulante natural. En aguas poco turbias como ésta, la velocidad de agitación tiene incidencia en la acción del clarificante, ya que este logra llegar hasta las partículas más dispersas aumentando la eficiencia del proceso de clarificación.
... Other natural materials were also appraised by many researchers to evaluate their potentials in water treatment. These include chitosan (Bina et al., 2009), wood ash (Jahn and Dirar, 1979; Jahn, 1988), nirmali and okra (Samawi and Shokralla, 1996), Azadirachta indica (neem) and Luffa cylindarica (Bhattarai et al., 2009), neem oil (Templeton et al., 2009), Cactus latifera (Alcantar et al., 2012), powdered roasted grains of maize (Rao, 2005), etc. The potentials of these natural materials in water purification were evaluated and documented, and found to be good coagulants, coagulant aids and/or disinfectants; some were even found to be very useful in hard water softening like M. oleifera (Muyibi and Okuofu, 1996). ...
Article
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Plant-based coagulants are potential alternatives to chemical coagulants used in drinking water treatment. This paper examined the turbidity removal efficiency of Tamarindus indica fruit crude pulp extract (CPE) towards evaluating a low-cost option for drinking-water treatment. Laboratory analysis was carried out on high turbidity raw water samples (i.e. 478 NTU) using T. indica CPE of concentrations ranging from 500 to 3000 mg/L as natural coagulant, using jar tests. Results obtained showed turbidity removal efficiency of the coagulant ranging from 64 to 99%. An optimum dose of 3000 mg/L resulted in highest turbidity removal efficiency of 99%. However, the treated water samples were observed to be of high acidity with pH values lower than 3.0, suggesting the need for pH adjustment. Nevertheless, this study demonstrated the potentials of T. indica CPE in coagulating high turbidity surface water. Keywords: Coagulation; crude pulp extract, pH, turbidity removal, T. indica
... Mucilage at high concentration could interacts with flocs formed after EC-EF process, which gave evidence that final larger flocs descend more rapidly depending on their size, enhancing thereby the effectiveness of the settling, due to high density difference [52]. These settling profiles are similar to those observed by Pichler et al. [53], different Opuntia spp. mucilage extracts were used to clarify kaolin turbid water by jar tests in comparison to the commercial flocculant; aluminum sulfate (Al 2 (SO 4 ) 3 ). ...
Article
Electrocoagulation-electroflotation (EC-EF) process assisted with the mucilage of Opuntia ficus indica (OFI) plant was investigated in order to enhance copper removal efficiency. EC-EF tests with aluminum electrodes were conducted for the treatment of a synthetic copper solution of 100 mg/L, to estimate the influence of the mucilage on removal of copper metal ions, aluminum and hydrogen Faradaic yields, settling process and specific electrical energy consumption. It was mainly found that: (i) copper removal efficiency reached 100% in < 5 min with 30 mg/L OFI mucilage at pH 7.8; (ii) OFI mucilage affected aluminum and hydrogen Faradaic yields at high removal efficiencies; (iii) copper sludge settling rate rises with increasing mucilage concentrations, and was enhanced by 15%; (iv) OFI mucilage reduced specific energy consumption at a fixed current density along with removal efficiency increase. Furthermore, the formed flocs, in the presence or not of mucilage, were identified by scanning electron microscope analysis (SEM). This work promotes the use of OFI mucilage as an active natural coagulant aid for the removal of copper species from water, by suggesting the substitution of chemical coagulants that are often added to the EC-EF technique.
... Opuntia spp. has been used earlier as natural coagulant for drinking water treatment [10][11] and treatment of industrial streams such as paint effluents [12]. However, as per our knowledge goes, it has never been tested for the treatment of TPW. ...
Article
In this study, the mucilage of Opuntia ficus-indica, a type of cactus was used as a bio-coagulant to treat tailings pond water (TPW) from the oil sands process industry. The performance of Opuntia ficus-indica was compared with conventional coagulants such as alum and ferric chloride for the removal of turbidity and dissolved organic carbon (DOC). Albeit at a higher dose of 900 mg/L, compared to that of alum (190 mg/L) and ferric chloride (104 mg/L), Opuntia ficus-indica could remove 98% of the turbidity of tailings pond water. The DOC removal was low for all coagulants and ranged from 15 to 28%, but acidification of TPW effluent improved DOC removal significantly. FTIR analysis showed the presence of oxidized napthenic acids and carboxylic groups on the surface of the TPW solids and flocs. The settling velocity of the flocs was 6.28 cm/min, 4.54 cm/min, and 3.01 cm/min generated by Opuntia ficus-indica, alum, and ferric chloride, respectively. Of several heavy metals present in TPW, Opuntia ficus-indica showed higher arsenic removal (64%) compared to alum and ferric chloride, while alum and ferric chloride showed significantly higher phosphorous removal compared to Opuntia ficus-indica. Activated carbon was used as the final treatment step for removal of residual organics; Opuntia ficus-indica treated TPW showed about 1.8 times greater adsorption capacity for activated carbon than that treated with alum.
... Con este estudio, se reafirma las bondades del mucílago de las plantas Cactaceae como agente coagulante en el proceso de clarificación de agua, tal como lo sugieren otros investigadores [16][17][18][19][20][21]. ...
Article
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In the clarification of the potable water chemicals like aluminum sulphate is use to remove coloidal matter and organic substances, improving the quality of the water. High residual aluminum concentrations in the potable water have implications in the human health, being necessary the alternative coagulants development, environmentally aceptable to replace them. In this investigation the properties that have the cactus Opuntia ficus-indica and alum in the water clarification of the Magdalena River in Magangué, Bolivar province (Colombia), as coagulant were evaluated. Finally, the efficiency that has mucilage extracted of the cactus Opuntia ficus-indica as natural coagulant was shown. In low-turbidity wáter like this, the agitation speed has an impact on the action clearer because this achieves reach the more dispersed particles increasing the efficiency of the clarification process.
... The Opuntia species in the cacti family had been known for its large production of mucilage, a complex used by the cactus to store water. The mucilage from the Opuntia ficusindica had been previously studied as a natural flocculants [25,42,47]. Mucilaginous cells containing mucilage were identified to exist in both the peel and pulp of the cathodes, ...
Conference Paper
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Reusing wastewater by effective treatment can contribute to counter the water scarcity. Conventional metal based coagulant treatment methods may prove inadequate to apply in aspects such as non-biodegradability and altered pH in post-treatment. There has been an extensive research on the use of biological plant material such as agricultural waste, Chitosan, Moringa Oleifera, Eichhornia crassipes, bark of acacia, Surjana seed, Maize seed, Tannin and Cicer aretinum etc. as a coagulant. In this study, the effectiveness of cactus as bio-coagulant for turbidity removal from municipal wastewater effluent has been studied. Effect of treatment on parameters such as pH, COD, and Suspended solids was also studied. The amount of dosage of cactus added was correlated with turbidity of wastewater. Depending upon turbidity of wastewater turbidity removal varies fro m 70 to 90% for dosage 30 to 100 mg/L. From this study, high turbidity removal indicates that cactus has the potential for wastewater treatment application.
... Con este estudio, se reafirma las bondades del mucílago de las plantas Cactaceae como agente coagulante en el proceso de clarificación de agua, tal como lo sugieren otros investigadores [16][17][18][19][20][21]. ...
Research
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In this investigation the properties that have the cactus Opuntia ficus-indica and alum in the wáter clarification of the Magdalena River in Magangué, Bolivar province (Colombia), as coagulant were evaluated. Finally, the efficiency that has mucilage extracted of the cactus Opuntia ficus-indica as natural coagulant was shown. In low-turbidity water like this, the agitation speed has an impact on the action clearer because this achieves reach the more dispersed particles increasing the efficiency of the clarification process.
... The cladodes are known to have medicinal value, used in the production of jellies, jams, natural food colorants and cosmetics (Hernandez-Perez et al. 2009). Attempts have been made to use cactus fruits and cladodes (succulent leaves) also for engineering applications such as for reduction of turbidity (Pichler et al. 2012, Saenz et al. 2004) and arsenic contamination (Young et al. 2005) in drinking water, reduction of hardness in spring waters (Young 2006), steel corrosion inhibition (Torres-Acosta 2007, Torres-Acosta et al. 2012), aluminum corrosion inhibition (El-Etre 2003), use as additive to reduce the permeability of mortar (Chandra et al. 1998), use as a viscosityenhancing admixture for cement mortar and concrete (Leon-Martinez et al. 2014) and for use as performance enhancement of lime-based mortar (Cardenas et al. 1998). Cactus cladodes, having the shape of a racket, serve as succulent leaves that store water for cactus plant. ...
Article
This research provides insight on the laboratory investigation of the engineering properties of a lateritic soil modified with the mucilage of Opuntia ficus-indica cladodes (MOFIC), which has a history of being used as an earthen plaster. The soil is classified, according to AASHTO classification system, as A-2-6(1). The Atterberg limits, compaction, permeability, California bearing ratio (CBR) and unconfined compressive strength of the soil were determined for each of 0, 4, 8 and 12% addition of the MOFIC, by dry weight of the soil. The plasticity index, optimum moisture content, swell potential, unconfined compressive strength and permeability decreased while the soaked and unsoaked CBR increased, with increasing MOFIC contents. The engineering properties of the natural soil, which only satisfies standard requirements for use as subgrade material, became improved by the application of MOFIC such that it meets the standard requirements for use as sub-base material for road construction. The effects of MOFIC on the engineering properties of the soil resulted from bioclogging and biocementation processes. MOFIC is recommended for use as a modifier of the engineering properties of soils, especially those with similar characteristics to that of the soil used in this study, to be used as a pavement layer material. It is more economical and environment-friendly than conventional soil stabilizers or modifiers.
... Los coagulantes naturales de origen vegetal como Moringa oleífera (Rodiño et al., 2015;Asrafuzzaman, Fakhuruddin, & Alamgir, 2011;Pritchard, Mkandawire, Edmondson, O'neill & Kululanga, 2010), cactus lefaria (Pichler, Young & Alcantar, 2012;Parra et al., 2011;Nirmala & Jadhav, 2012) almidón de yuca (Rodríguez et al. 2007;Hamidi & Koffly, 1998) y algas marinas (Prado et al. 2011;Kawuamura, 1991); resultan ser biodegradables, económicos, seguros por su compatibilidad con el medio ambiente (Poumaye et al., 2012;Pritchard et al., 2010); gracias a la presencia de proteínas solubles que actúa en el proceso como un polielectrolito catiónico natural (Barth et al., 1982;Jahn, 1988), capacidad que se incrementada cuando se emplean sales inorgánicas como pre-tratamiento (Okuda et al., 1999); No inciden significativamente en los cambios de pH y conductividad del agua después de su tratamiento (Ndabigengesere y Narasiah, 1998) y reducen la presencia de microorganismos (Huda et al., 2012, Ghebremichael et al., 2005. ...
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Introduction. Surface water is most important as a source for supply, but not all of it is suitable for consumption. It is necessary to treat it by combining physical and chemical processes that require the use of coagulants such as the aluminum sulfate, a substance that is efficient but it is also harmful for health, as human beings bio-accumulate it. Objective. Evalúate the efficiency of the natural coagulants: Moringa Oleífera, Opuntia cactus, seaweed and starch, to clarify human consumption water, as a substitute of the aluminum sulfate in batch and continuous systems. Materials and methods. Water samples from the Cesar river were analyzed during sunny and rainy periods, representing low and high turbidity. The biomasses were analyzed with and without chemical pre-treatments (Ca(OH)2, CaCL2, NaOH y NaCl). Tests were performed by means of two systems that simulated the coagulation and flocculation stages, with several doses. The control variables were color, turbidity, OD, ST, conductivity, COD and pH. Results. The highest removal efficiencies were found with pre-treatments, except with the cactus, finding 88.26% for moringa using Ca(OH)2, 79.73% for starch with NaOH; 81.14% for algae with CaCL2 and 98.41% for cactus, which is the most efficient. An efficient behavior was obtained from the continuous system with similar conditions to those obtained from the batch system. Conclusions. The optimal conditions of the natural coagulants were determined, demonstrating their efficiency, safety and economy for water treating, with less mud generation, thanks to the adsorption and load neutralization mechanisms.
... This method does not affect these parameters. [8] By comparing these results with others obtained by several bioflocculant ,we find that this result is better than those obtained by different researchers who worked on mucilage and cactus powders and with biopolymers where we were able to have very high reduction rates at very low volumes. [ 9;10;11]. ...
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This present study deals with the preparation and application of a new biodegradable, non-polluting and economical bioflocculant based on available natural cactus cladodes (Opuntia Ficus Indica) for water clarification. The main objective of this work is to replace conventional commercial products such as chemical coagulants (FeCl3, Al2(SO4)3), synthetic organic polymers(anionic, cationic or non-ionic) proving inadequate, unsuccessful or expensive to apply and to be able to meet increasingly stringent standards. The use of this new generation of biomaterials should reduce the cost of water treatment in health, environmental and sustainable development context. The efficiency of this new gelled product is evaluated through several Jar Test tests, both for synthetic and real water samples, by examining some parameters deemed useful in eliminating turbidity. These parameters are turbidity, pH, bioflocculant concentration and conductivity of water. The present results showed overall and clearly that the maximum reduction in the turbidity of synthetic water is obtained for a very low volumetric ratio (gelled flocculant/water sample). Throughout all the pH range studied, very high reduction rates were obtained with a residual turbidity meeting the standards and without affecting the pH and conductivity of treated samples. The application of this biomaterial towards some surface water samples from the river of Hammam Melouan (Oued El Harrach) has given encouraging results where the obtained turbidity abatement rate seems to be important for all the pH range studied. The Flocculation studies proved the cactus gel to be the most effective flocculating agent when compared to conventional commercial products and other bioflocculants. According to the results obtained this Ecofriendly biomaterial can be attributed as an alternative solution to problems associated with the environmental performance of chemical coagulants.
... Regardless the origin of these green extracts and their active agent content, plant-based coagulants/flocculants have been prepared as follows ( Fig. 1): (i) Plant parts were firstly cut, sliced or peeled, then oven or sun-dried and grinded to obtain a readily usable fine powder. (ii) For further usage, the dried powder can be either dissolved in water, in salt solutions (NaCl, KCl, MgCl 2 , etc.) (Okuda et al. 2001) or in organic solvents (acetone, alcohol) (Pichler et al. 2012) to form a mucilaginous filtrate. From the ecological standpoint and environmental benefits, extraction using only water or salt solutions should be recommended over the use of organic solvents to minimize environmental burdens. ...
Article
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Abstract Plant based coagulants/flocculants are foreseen to be a major progress in waters treatment technology owing to their safety, biodegradability and availability, unlike synthetic chemicals water refiners such as Al, Fe salts, and organic polymers claimed to cause threats to our ecosystem either via their residues in the treated waters or due to their toxic generated sludge. Further, the increasing global awareness about environmental issues is acting as the driving force behind the interest toward the use of green resources as valuable products for waters treatment. Substitution of synthetic coagulants/flocculants by such natural materials can not only minimize ecosystem damages and threats, but would also foster the way towards an era of clean technology and a sustainable environment. The present paper reviews works on the most efficient model plant based coagulants/flocculants; Moringa seeds, Cactus pads, Okra seed pods and Mango kernels; via highlighting their effectiveness in treating a variety of waters. This review focus also on the extracting processes used for their preparation, on the type of their active compounds as well as on waters pollutants removal mechanisms. Among the four known coagulation-flocculation phenomenon, both polymer bridging and charge neutralization were assumed to be the main predominant mechanisms of bio-coagulants/bio-flocculants towards water contaminants removal. Further, the paper sheds light on where future works should head with the aim of stressing the exploitation of green materials in water remediation. We believe that this review can provide an immediate platform for scientists to intensify their research on more efficient natural products to be used in water processing for the sake of a safer environment. Keywords: plant based coagulant/flocculants; waters treatment; bio-flocculants; coagulation-flocculation; clean technology.
... (Bayar et al., 2017;Peña-Valdivia & Sánchez-Urdaneta, 2006), and these complex polysaccharides have been shown to possess hydrophilic and gelling properties with a number of practical applications (Bayar et al., 2016). Mucilage, in particular, has been shown to flocculate and precipitate sediment particles in aqueous solutions (Pichler et al., 2012), indicating an increase in particle density. Because particle density is a major factor affecting rumen outflow of feed particles (Kennedy, 2005), it may be argued that an increase in particle density induced by mucilage could contribute to faster passage of rumen digesta when CC are included in cows' diets. ...
Article
Based on low 18:0 contents observed in milk fat of cows fed cactus cladodes (CC), we hypothesized that including Opuntia stricta c ladodes i n a s oybean o il ( SO)- supplemented diet would promote incomplete rumen biohydrogenation of supplemental PUFA, leading to increased trans-11 18:1 and cis-9, trans-11 CLA contents in milk. Twelve Holstein cows were used in a two-period study: (a) Baseline: all cows received a total mixed ration (TMR) composed of sorghum silage (SS) and a concentrate containing no SO for 14 days; (b) Treatment: cows received one of the following SO-supplemented diets for 21 days: (1) SS-TMR: a TMR composed of SS and a SO-enriched concentrate, (2) CC-TMR: a TMR containing CC as a partial substitute for SS plus the SO-enriched concentrate, and (3) CC-PMR: same diet as in treatment 2, but CC were mixed with the SO-enriched concentrate and fed as a partial mixed ration (PMR). Both CC diets increased relative abundances of trans-11 18:1, cis-9, trans-11 CLA, and 18:2 n-6 in milk fat, whereas opposite effects were observed on 18:0 and cis-9 18:1. Proportion of 18:2 n-6 increased, and cis-9, trans-11 CLA tended to increase with CC-PMR as compared to CC-TMR, whereas 18:3 n-3 was higher with CC-PMR than with SS-TMR. Proportions of several odd- and branched-chain fatty acids, certain 18:1 isomers, and trans-9, cis-11 CLA changed with CC diets, notably with CC-PMR. Milk yield and intake of most nutrients (except fibre) increased or tended to increase with the CC diets, whereas gross milk composition was unaltered. Stearoyl-CoA desaturase-1 index for C18 (SCD18) was higher with CC-PMR than with SS-TMR, and milk n-6:n-3 FA ratio and apparent transfer of 18:2 n-6 to milk increased with CC diets. These results indicate that Opuntia stricta cladodes can be a valuable feed ingredient for improving the nutraceutical value of milk fat.
... (Bayar et al., 2017;Peña-Valdivia & Sánchez-Urdaneta, 2006), and these complex polysaccharides have been shown to possess hydrophilic and gelling properties with a number of practical applications (Bayar et al., 2016). Mucilage, in particular, has been shown to flocculate and precipitate sediment particles in aqueous solutions (Pichler et al., 2012), indicating an increase in particle density. Because particle density is a major factor affecting rumen outflow of feed particles (Kennedy, 2005), it may be argued that an increase in particle density induced by mucilage could contribute to faster passage of rumen digesta when CC are included in cows' diets. ...
Article
Based on low 18:0 contents observed in milk fat of cows fed cactus cladodes (CC), we hypothesized that including Opuntia stricta cladodes in a soybean oil (SO)- supplemented diet would promote incomplete rumen biohydrogenation of supplemental PUFA, leading to increased trans-11 18:1 and cis-9, trans-11 CLA contents in milk. Twelve Holstein cows were used in a two-period study: (a) Baseline: all cows received a total mixed ration (TMR) composed of sorghum silage (SS) and a concentrate containing no SO for 14 days; (b) Treatment: cows received one of the following SO-supplemented diets for 21 days: (1) SS-TMR: a TMR composed of SS and a SO-enriched concentrate, (2) CC-TMR: a TMR containing CC as a partial substitute for SS plus the SO-enriched concentrate, and (3) CC-PMR: same diet as in treatment 2, but CC were mixed with the SO-enriched concentrate and fed as a partial mixed ration (PMR). Both CC diets increased relative abundances of trans-11 18:1, cis-9, trans-11 CLA, and 18:2 n-6 in milk fat, whereas opposite effects were observed on 18:0 and cis-9 18:1. Proportion of 18:2 n-6 increased, and cis-9, trans-11 CLA tended to increase with CC-PMR as compared to CC-TMR, whereas 18:3 n-3 was higher with CC-PMR than with SS-TMR. Proportions of several odd- and branched-chain fatty acids, certain 18:1 isomers, and trans-9, cis-11 CLA changed with CC diets, notably with CC-PMR. Milk yield and intake of most nutrients (except fibre) increased or tended to increase with the CC diets, whereas gross milk composition was unaltered. Stearoyl-CoA desaturase-1 index for C18 (SCD18) was higher with CC-PMR than with SS-TMR, and milk n-6:n-3 FA ratio and apparent transfer of 18:2 n-6 to milk increased with CC diets. These results indicate that Opuntia stricta cladodes can be a valuable feed ingredient for improving the nutraceutical value of milk fat.
... Dikenli incir, ayrıca hayvan yemi, atık suların arıtılması [24,25], erozyon kontrolü ve arazi ıslahı gibi pek çok alanda da değerlendirilmektedir [26,27,28]. ...
Article
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Dikenli incir (Opuntia Ficus-İndica L.) Amerika ve Avrupa’da üretilen ve tüketilen bir meyve olmasına karşın ülkemizde sadece kıyı bölgelerdeki şehirlerde yetiştirilmektedir. Tüketiciler tarafından yerel pazarlara çıkış zamanları yoğun olarak takip edilen bir meyvedir. Bu çalışmada, dikenli incir üretim olanaklarının artırılması; ticari anlamda da üretilmesi ve işlenmesi amacı ile bitki tohumlarına ait bazı fiziksel özellikler belirlenmiştir. Çalışma 2018-2019 yılları arasında yürütülmüştür. Akdeniz bölgesinden toplanan on dört farklı genotipe sahip dikenli incir meyvelerinden elde edilen tohumların bazı fiziksel özellikleri (şekil-boyut, yüzey alan, ortalama aritmetik-geometrik çap, küresellik, bin dane ağırlığı) belirlenmiştir. Elde edilen veriler p<0.05 önemlilik düzeyinde istatistiki olarak da incelenmiştir. Dikenli incir tohumlarının genel olarak 2.255-2.524 mm arasında değişen uzunluğa ve 1.666-2.044mm genişliğe sahip olduğu belirlenmiştir. Tohumların kısa ve oval bir yapıya sahip olduğu; 4.097-6.250 g bin dane ağırlığına sahip olduğu belirlenmiştir. Bu çalışma ile dikenli incir üretim ve yetiştirilmesi yanında özellikle ürün işleme basamağında tohumların meyveden ayrılarak değerlendirilmesi, uygun alet-makine tasarım ve üretimine katkı sağlaması amaçlanmıştır.
... Sedimentation method by coagulants to remove turbidity water is the best and least expensive comparison to other methods and it is recommended for primary water treatment for drinking water treatment (Pichler et al., 2012). ...
Article
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Turbid water has a significant harmful effect on water pollution which is included suspended solids and colloidal materials such as clay, silt and its contents of organic, inorganic materials and microorganism. Sedimentation method by coagulants is the best and least expensive process comparison to other methods, it is recommended for primary water treatment. Inorganic compounds such as aluminum sulfate (alum) are widely used as a coagulant, but it has caused many problems for human's health .Therefore many studies attempt to find eco-friendly natural coagulant as an alternative of chemical material for water treatment. This study comprised using cactus mucilage extract as a mainly coagulant as well as used a coagulant aid with alum by jar test apparatus to treat three levels of turbid water 53,100 and200 NTU at pH ranging between 4-10,varoius temperatures and several intervals of settle were examined in study. Results indicated that the optimum dosages of natural coagulant were 5,10 and30 ppm at pH 7 and the best period of sedimentation was 2 and 5 hours with significant turbidity removal 79.3%, 78.7%, 82% and 84.7%, 86.6%, 87.9% for two time and three levels of turbid water respectively, while there is non-significant difference between various temperatures in treatment. This study shows integrated natural coagulant with alum obtained maximum turbidity removal at ratio (0.5:0.5) (coagulant aid: alum) that were 74.1%, 84.7% and 89.8% for three levels of turbid water respectively.
... Pichler et al. [60], studied the natural coagulants through a comparison model, using mucilage from Opuntia ficusindica obtained from Tucson, Arizona against aluminum sulfate (Al 2 (SO 4 ) 3 ), the commonly used synthetic flocculant. After performing experiments tests, the results demonstrated high efficiency of the cactus mucilage in eliminating turbidity. ...
Article
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In Morocco, the increasing production of municipal solid waste (MSW) and its by-products, in particular leachate, is a major concern. MSW leachate is a very complex effluent, loaded with organic and inorganic pollutants; it poses a serious threat to human health and the environment. In Agadir city, the leachate generated is stored in seven tanks in the Tamellast landfill. The daily flow of this effluent accelerates the saturation of the storage tanks. Overflowing leachate presents a potential environmental hazard, and proper treatment of the leachate has inevitably become a requirement. Therefore, this study aims to find a simple, inexpensive and efficient leachate treatment system. Two techniques using local natural materials have been combined to achieve significant results: coagulation and infiltration-percolation. Cactus powder and cactus mucilage have been selected to treat leachate by coagulation and titaniferous sand as a filter material for the infiltration-percolation process. Laboratory scale experiments show very interesting results. Due to its effectiveness at a dose of 20 mg / l at pH 11, the effluent treated with cactus mucilage was chosen to undergo secondary treatment (86.54% for turbidity and 14.60% for electrical conductivity). The elimination of turbidity and electrical conductivity achieved after infiltration-percolation is, respectively, 97% and 39%. Graphic abstract
... They have medicinal attributes such us wound, burn, and ulcer healing, as well as antidiabetic and antiglycation effects [3,4]. Other mucilage applications include its use in foods as a stabilizer, flavoring agent, fat substitute [5], and edible coating to extend the useful life of fruit [6], among others [7,8]. ...
Article
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Cactaceae and Asphodelaceae are native desert plants known for their high mucilage content, which is a polysaccharide of growing interest in the food, cosmetic, and pharmaceutical industries. In this study, powdered mucilage was obtained from cladodes of Opuntia ficus-indica (OFI) and aloe vera (AV) leaves, and their molecular, morphological, and thermal properties were investigated and compared. Additionally, their dietary fiber content was determined. Three-dimensional molecular models were calculated for both mucilages using ab initio methods. Vibrational spectra (FTIR and Raman) revealed intramolecular interactions and functional groups that were specified with the help of theoretical ab initio and semi-empirical calculations. SEM micrographs measured at magnifications of 500� and 2000� demonstrated significantly different superficial and internal morphologies between these two mucilages. Thermal analysis using DSC/TGA demonstrated superior thermal stability for the OFI mucilage. The dietary fiber content in OFI mucilage was more than double that of AV mucilage. Our results show that both dehydrated mucilages present adequate thermal and nutritional properties to be used as functional ingredients in industrial formulations; however, OFI mucilage exhibited better physicochemical and functional characteristics than AV mucilage as a raw material.
... The turbidity parameter is an indication of the presence of suspended particles and organic matter in wastewater (Pichler et al., 2012). In the present work, the turbidity value was lower in relation to the others, except for Huang et al. (2019). ...
Article
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Laundry wastewater has a high amount of dirt from the washed items and chemical additives used in washing process. Aiming the primary treatment of this type of wastewater, three different natural coagulants (Tanfloc POP, Tanfloc SL, and Tanfloc SG) were evaluated in the removal of color and turbidity by the coagulation/flocculation/sedimentation process (C/F/S). The results showed that the time between 5 and 10 min was sufficient for the sedimentation of the flakes, with a time of 10 min being adopted for further studies. The statistical analysis and the cost of acquiring the coagulant were decisive in the selection of the best natural coagulant. The maximum values of color (88.7%) and turbidity (92.8%) removal efficiency occurred at a concentration of 120 mg L−1 (concentration determined by the Fischer LSD test) and the lowest cost (0.75$) obtained for the Tanfloc POP coagulant. The volume of sludge generated was higher in the treated effluent sample compared to the control sample, which proves the removal of total solids present in the effluent. The Tanfloc POP coagulant showed a high performance in removing color and turbidity from industrial laundry wastewater; it has been as a promising coagulant in the primary treatment of wastewater in this service sector.
... These are primarily used for animal feed, left between orchard rows, or incorporated into the soil. This annual pruning waste provides an excellent opportunity for adding value to this crop by extracting mucilage from the pads for industrial purposes (Sepúlveda et al., 2007;Iturriaga et al., 2009;Pichler et al., 2012). Another mucilage application is production of edible films and coatings for highly perishable fruits such as guava (Psidium guajava L.). ...
Article
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Annual pruning of cactus pear cladodes provides an opportunity for adding value to this crop by extracting mucilage from which to create edible films and coatings for perishable fruits such as guavas (Psidium guajava L.). The objective of this research was to create mucilage films and assess their effects on quality and shelf life of guava cultivar 'Media China'. Cactus pear cladodes were peeled, cubed, and homogenized in distilled water. Mucilage was precipitated using ethanol, then dried and ground. The experimental films tested were: no films as control (C), mucilage plus glycerol (T 1), and mucilage plus glycerol and polyethylene glycol (T 2). Two experiments were conducted with two different concentrations of mucilage, glycerol, and polyethylene glycol. Guavas were harvested from local farmers and treated with a fungicide before coating. The treated fruit was stored for eight or six days at room temperature (28°C and 20% RH or 27°C and 20% RH, respectively). In the first trial, the T 2 film increased fruit weight loss more than C and TI film. Both films delayed fruit skin colour and maintained higher firmness (F), total soluble solids concentration (TSSC), and dry matter concentration (DMC) than C fruit. In the second trial, T 1 and T 2 films reduced fruit weight loss and delayed fruit skin colour more than C fruit. Firmness, TSSC, and DMC of fruit were similar among treatments. Overall, the experimental mucilage films showed a tendency to prolong shelf life and maintain some quality attributes of guava. Further research is needed to understand the mucilage potential as an edible film at cold room conditions.
... The genus Opuntia, similarly to other cacti, is known by the capacity to produce and store mucilage (Peña-Valdivia et al., 2012), a complex carbohydrate formed by arabinose, galactose, rhamnose, xylose, and uronic acids (Matsuhiro et al., 2006), which can imbibe large quantities of water (Saenz et al., 2004), and this is an important factor in the adaptation of the plant to warm and dry environments (Cardenas et al., 1997). The mucilage has found application in effluent treatments (Miller et al., 2008), in water purification for human consumption (Pichler et al., 2012), and in pharmaceutical to favor suspending, thickening, binding, emulsifying, and stabilizing of suspensions (Malviya et al., 2011). Further, the characterization of mucilage of cactus stems has been carried out to evaluate its use as a nourishing additive, either as a viscosity-increasing agent or together with other gums to obtain a synergistic effect with such polymers (Yahia, 2012). ...
Article
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Mucilage from stems of cactus (Opuntia ficus-indica) ‘Milpa Alta’ (Mm) and ‘Toluca’ (Mt), in a single ingredient conditon and in mixture with gelatin and beswax, was used to prepare biopolymeric films, which were asesed in terms of microscopic morphology, thicknes, transparency, tensile strength, and permeabilty to water vapor, O2, and CO2. Films based on Mm were thiner, with higher transparency, and higher tensile strength than those of Mt, but they had similar barier properties to water vapor, O2, and CO2. The aditon of gelatin did not afect thicknes and transparency of such films, but caused modifcation of the microscopic morphology, the mechanical strength, and the barier properties to gases and water vapor. Furthermore, the aditon of beeswax promoted the formation of agregates in the microscopic morphology of films and these acquired smaler thicknes, higher tensile strength, and higher barier properties to O2, CO2, and water vapor, which may give them beter potential to be used in the postharvest conservation area of horticultural products, although they were les transparent.
... In addition to its medicinal properties, mucilage obtained from pads is a potential source of hydrocolloids, which are useful in cosmetic applications [12]. Some studies have reported its use in water purification or filtration [16]. Opuntia spp. ...
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The current study was aimed at developing BC-Cactus (BCC) composite hydrogels with impressive mechanical features for their potential applications in medical and environmental sectors. BCC composites hydrogels were developed through cactus gel coating on a never dried BC matrix. The FE-SEM micrographs confirmed the saturation of BC fibrils with cactus gel. Additionally, the presence of various functional groups and alteration in crystalline behavior was confirmed through FTIR and XRD analysis. Mechanical testing illustrated a three-times increase in the strain failure and an increase of 1.6 times in the tensile strength of BCC composite. Absorption capabilities of BCC were much higher than pure BC and it retained water for a longer period of time. Additionally, the rewetting and absorption potentials of composites were also higher than pure BC. The composite efficiently adsorbed Pb, Zn, Cu, and Co metals. Biocompatibility studies against human HaCat cell line indicated much better cell adhesion and proliferation of BCC compared to BC. These findings advocate that the BCC composite could find applications in medical, pharmaceutical and environmental fields.
... In the study conducted and reported in [20], different investigations have used cactus fruits and cladodes (succulent leaves) industrially, such as in limiting turbidity in H 2 O, removal of arsenic contamination in consumable water, decrease in the hardness of spring H 2 O [21,22], prevention and inhibition of steel corrosion [23,24], and aluminum corrosion [25]. MOFIC has been reported to contain arabinose, carbohydrates, galactose, xylose, rhamnose, galacturonic acid, Ca 2+ and K + [26]. ...
Article
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This study investigates the effects of mucilage from Opuntia ficus-indica cladode (MOFIC), a bio-modifier, on Lime-stabilized Lateritic soil's durability and index features. Specifically, this research assessed the alterations to the Atterberg limits, compaction characteristics, California bearing ratio (CBR), index values and the unconfined compressive strength (UCS) properties of the soil samples and the stabilised samples through laboratory experiments. Lime + MOFIC was added to the soil at 0%, 2%, 4%, 8%, 12% and 16% wt (%) of soil. The result confirms alteration in the index and strength characteristics of the soil upon the addition of MOFIC to the Lime-treated Lateritic soil. The geotechnical characteristics of the soil improved from a subgrade soil to a subbase material upon the addition of 2% of LIME + MOFIC; with the presence of Lime + MOFIC at 2–4%, the bearing capacity of the soil improved from a subgrade material to a subbase material according to the Nigerian General Specification. The highest CBR value in Lime-stabilised was 56%, while the CBR value of Lime + MOFIC-stabilised soil was 70%. This represents a 20% increment in CBR. The presence of polysaccharides in MOFIC enhanced the soil binding attributes of the Lime and hence accelerated the strength properties of the soil. The promotion of green construction and reduction in environmental impacts of using Lime motivates the use of MOFIC in the study. Based on the result of the experimental research, MOFIC is thereby recommended as an eco-friendly alternative for enhancing engineering properties of pavements interlayers. The addition of MOFIC improved the index and strength properties of pavement interlayer material in road construction.
Conference Paper
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This study investigated the effect of coagulation process on wastewater from latex concentrate industry. The coagulation performances of dragon fruit's foliage which was a newly invented plant based coagulant and commercial coagulants such as alum, ferric chloride, polyaluminium chloride, magnesium chloride, ferrous sulfate, ferric sulfate and calcium hydroxide were studied using a jar test. The study also compared different dosages and pH values of the coagulation processes. The analysis of dragon fruit's foliage was also studied. The results revealed that the percentage removals in terms of COD, SS and turbidity of commercial coagulants (alum, ferrous sulfate, calcium hydroxide, PAC, ferric chloride and ferric sulfate) have been found to be around 97-99%, 94-97% and 99% respectively, whereas the newly invented plant-based coagulant at the same dosage of 300 - 600 mg/L demonstrates the same performances as any commercial coagulants. All the coagulants used give high percentage of BOD removal which is from 1327 mg/1 before treatment to below 100 mg/1 after treatment except for dragon fruit coagulants which gives 173.67 mg/L. However, others parameters such as sulfate, NH3-N and several heavy metals are in compliance with standard B set by Department of Environment, Malaysia. The study has proven the existence of alum compound in the dragon fruit's foliage under the XRay Diffractometer (X-RD) analysis and therefore the dragon fruit's foliage can be used as a coagulant and has a great potential as a new plant-based coagulant in latex concentrated wastewater treatment.
Chapter
Water is the most abundant and essential resource in India. At present, the quality of water resources is one of the most critical environmental challenges from the national perspective. Increasing population coupled with rapid urbanization, industrialization, and agricultural growth has resulted in the deterioration of water quality in the country. The available water resources in many parts of the country are becoming polluted because of the discharge of untreated sewage, industrial effluents, etc. This pressing situation demands a solution to improve the quality of water resources in the country through water quality management strategies.
Conference Paper
Micro to nano-scaled structures are progressively being integrated into semiconductor architecture and will have a global impact on filtration, biosensing, and energy storage. These structures include micro and nano sized fiber membranes for electrodes, nanolaminates for trenched capacitors, or nanofiber membranes for sensing and actuating. For integrated circuit innovations, the ultimate thrust is to provide superior functionality and structural durability without adversely impacting the environment. As micro to nano-scaled structures rapidly progress toward scalable manufacturing, it is critical and timely to conduct fundamental investigations on assessing material composition impacts on functional failures and environmental sustainability. This research uses a failure and life cycle assessment (FLCA) process to understand material composition influence on micro and nano structure 1) properties, 2) performance limiting defects (failure), and 3) environmental impacts The FLCA integrates multiple characterization stages, performance testing, and environmental assessments of fiber membranes. This work will have a long-term impact on the integration of nanoscaled structures into emerging electronic materials per the International Technology Roadmap for Semiconductors (ITRS) and identifying a transferable process for a FLCA to evaluate polymer nanofiber technology for ICs.
Article
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The peels obtained as a byproduct from the processing of fruits (prickly pears) of the Cactaceae family are a rich source of mucilage, a hydrocolloid biopolymer that may have potential application in water/wastewater treatment as a natural coagulant. In this study, the structural (UPLC-QTOF-MS, FTIR, Raman, NMR, XRD, and zeta potential), morphological (SEM), and thermal (DSC/TGA) characterizations of the mucilage extracted from the peels of Opuntia ficus-indica (OFI) fruits were carried out. UPLC-QTOF-MS results revealed the presence of a branched polymer with an average molecular weight of 0.44 KDa for this mucilage in aqua media. The NMR spectra of mucilage in DMSO-d6 indicated that it seemed well-suited as a coagulant with its typical oligosaccharide structure. FTIR studies confirmed the presence of hydroxyl and carboxyl functional groups in the mucilage, indicating its polyelectrolyte nature that could provide coagulating properties through binding and adsorption mechanisms. Likewise, the zeta potential of −23.63 ± 0.55 mV showed an anionic nature of the mucilage. Power XRD technique evidenced the presence of crystalline poly(glycine-β-alanine), glutamic acid, and syn-whewellite. SEM images revealed an irregular and amorphous morphology with cracks, which are suitable characteristics for adsorption mechanisms. The mucilage exhibited two endothermic transitions, with a decomposition temperature in uronic acid of 423.10 ◦C. These findings revealed that mucilage obtained from OFI fruit peels has molecular and physicochemical characteristics that are suited to its possible application as a natural coagulant in water/wastewater treatments.
Research
Summary This dissertation deals with two research themes: technologies dedicated to wastewater treatment and reuse as well as the occupational exposure to organic solvents via investigating on their quantification in working environment and their effect on human health. Research on these 2 themes started in 2003 in the Laboratory of Water Energy and Environment at ENIS. Different technologies devoted to wastewater treatment were developed and tested for their efficiency with the cooperation of some industries in the region of Sfax. Either the fundamental or the applied aspects were addressed. Among the investigated technologies, ozonation, electrochemical treatment and coagulation-flocculation processes are the most evaluated ones along this research work. Each technology has its advantages and disadvantages depending in the wastewater quality and the objective of its faith after the treatment. It was recommended that advanced oxidation process using ozone and H2O2 could be efficiently used as a preliminary treatment for a biological process with the aim of persistent and emerging pollutants biodegrability enhancement and cost treatment reduction in the case of textile wastewater. As to electrochemical processes, there were found suitable for the treatment of wastewater bearing recalcitrant compounds such as textile and olive mill wastewaters. Treatment extend was monitored using uncommon analytical tools seldom exploited in the field of wastewater treatment, for instance NMR, CG/MS and Cyclic voltametry. On another hand, for the time being, due to the current extensive treatment using the flocculation-coagulation process resulting in an abundant use of chemicals reagent threatening thus our environment, a plant-based flocculent was introduced and tested for its efficacy in this above mentioned process. Obtained results are promising in term of pollutant removal and could lead also to a valorization of one of our Tunisian neglected bioressources, the plant cactus. In overall, it was thought that this work should contribute to the improvement of the efficacy of the applied wastewaters treatment techniques from the technical and ecological standpoints. Valorization of some types of the treated wastewater in the irrigation field was also addressed using a plant model. As to the second theme, it deals with organic solvents detection and occupational exposure assessment. To do so, chromatographic methods, such as HPLC-UV and GC-FID were validated and exploited in a routine way to detect organic solvents used in working environment of some industrial activities as well as to quantify their metabolites in urines samples of workers exposed to such chemicals. Obtained results were compared to the international guidelines and were found in most cases by far exceeding the occupational exposure limits values. Metabolites of some organic solvents showed correlation with solvents concentration in the air working places. Moreover, although benzene is prohibited from any industrial use, its metabolite is still found in urines workers samples. Shoes making factories workers were the most touched persons by this solvents exposure among the studied populations. As to the best of our knowledge, this is the first investigation on exposure to organic solvents in the adhesive, shoes making and washer and dry cleaning enterprises in Tunisia. We believe that it can help decision-makers to set Tunisian Guidelines for solvents exposure and improve work conditions in such industries.
Article
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The cactus tree, species Opuntia ficus-indica, is a primary material of many products in various domains such as cosmetics, medicine and nutrition. In the present work, we assess its potential as a flocculant. We tried a technique which adopts three sequential treatments that used coagulation, flocculation and sedimentation processes under certain operating conditions. For this purpose, we used the aluminum sulfate (AS) as coagulant and fresh cladodes juice (FCJ) as bioflocculant. All tests were carried out on high turbid urban wastewater collected from the Metlaoui's Wastewater Treatment Plant (MWTP) (in Gafsa in southwest Tunisia). Experiments with this couple AS/FCJ show very interesting results: a high-removal of turbidity (TUR), suspended solids (SS) and chemical oxygen demand (COD). The percentages of abatement of these parameters are respectively 93.65%, 82.75% and 64.30%. The experimental results of the present study prove that the turbidity, SS and COD removal efficiency of new technique is superior to that of conventional process (with only AS). By this technique, we save 50% in AS dose. Moreover, flocs formed by the treatment using AS/FCJ are coarse and readily settleable.
Article
Pollution caused by wastewater is a serious problem in Algeria. This pollution has certainly harmful effects on the environment. In order to reduce the bad effects of these pollutants, many wastewater treatment processes, mainly physico chemical are implemented, In this case, the method most used is the physical-chemical coagulation-flocculation process. The procedure is based on the use of aluminium and iron salts alone or in combination with the use of two flocculants; the first one is a biodegradable natural bioflocculant Opuntia cactus juice, and the second is the synthetic hydroxyapatite; to treat waste water collected at the entrance of the treatment plant, in the town of Saida. The flocculants were characterized using Fourier transform infrared spectroscopy, The influence of various experimental parameters, such as the amounts of coagulants and flocculants used, pH, turbidity, COD and BOD5, was investigated. The coagulation—flocculation jar tests of wastewater reveal that ferric chloride, containing a mass of 0.3 g hydroxyapatite is the most effective adjuvant in clarifying the wastewater, with turbidity equal to 98.16%. In the presence of the two bioflocculants, Opuntia cactus juice and aluminum sulphate, with a dose of 0.2 g, flocculation is good, with turbidity equal to 95.61%. The examination of the main parameters studied during the flocculation tests shows that the degree of pollution decreases, this is confirmed by the COD and the turbidity values. Analysis of these results suggests the use of these flocculants in wastewater treatment.
Chapter
In recent years, increased industrial and agricultural activities and the correlated population growth led to overexploitation of natural resources and the increased generation of various types of pollutants. For these reasons, the hazardous pollution of wastewater is one of the most important environmental problems worldwide. A wide range of wastewater treatment technologies are available; however, some disadvantages are often reported. Hence, there is a constant need to search for an efficient, low-cost and alternative wastewater treatment. Recently, several biosolids have been considered for pollutant removal from wastewaters, including Opuntia ficus-indica. This chapter focuses on wastewater treatment strategies involving material parts in sewage containing high levels of chemical oxygen demand and turbidity, heavy metals and pesticides.
Preprint
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Reusing wastewater by effective treatment can contribute to counter the water scarcity. Conventional metal based coagulant treatment methods may prove inadequate to apply in aspects such as non-biodegradability and altered pH in post-treatment. There has been an extensive research on the use of biological plant material such as Agricultural waste, Chitosan, Moringa Oleifera, Eichhornia crassipes, Bark of acacia, Surjana seed, Maize seed, Tannin, Cicer aretinum, Cactus plant etc. as a coagulant. The present paper review to explore the use of cactus species in the bio-coagulation process and also it aims about investigation on effectiveness of cactus species Opuntia Ficus Indica as bio-coagulant which involve pH implication in post-treatment. In addition, the cactus had no significant effect on pH of treated water. This review highlights about optimum dosage and optimum pH at which turbidity removal is maximum. Some studies show the effectiveness of cactus in removing chemical oxygen demand (COD) and coloration in wastewater. Plant-based coagulants have the potential are effective in wastewater treatment which is sustainable and environmentally appropriate. The bio-coagulant proved to be efficient in turbidity and colour removal.
Article
Laundries use in their washing process various chemical inputs, which give to their effluents alkalinity, organic load, color, suspended solids and surfactants, and these effluents cause damage to aquatic ecosystems if discarded without treatment. Hence, the effluent from this type of activity requires adequate treatment. Therefore, the aim of this work was to treat the effluent from an industrial laundry by a sequential process of coagulation/flocculation/sedimentation-adsorption-microfiltration (C/F/S-ADS-MF) and evaluate the final treated water quality. In the C/F/S stage, the statistical analysis (ANOVA, p-value<0.05; Fisher’s test, p-value > 0.05) indicated that 140 mg L⁻¹ was the best natural coagulant concentration. To surfactants adsorption by activated carbon, the contact time required to establish the system equilibrium was 10 h, and the kinetic model of pseudo-second-order best represented the experimental data. The MF presented a permeate flux of 60.51 L h⁻¹ m⁻². The water quality parameters were improved with sequential process application, resulting in global removal efficiency of 99.9% for color, 80% for chemical oxygen demand, 92.9% for surfactants and 99.4% for turbidity. Therefore, the proposed sequential process showed to be a promising technique for industrial laundry wastewater treatment.
Article
A natural surfactant was studied to simulate the dispersion process of crude oil in water. The interfacial phenomena of this natural dispersant was compared with a commercially-available chemical dispersant, COREXIT® EC9500A. This functional surfactant was extracted from the mucilage of the Opuntia ficus-indica cactus species. The evaluation to determine the efficacy to disperse crude oil of the cactus-based mucilage extract (non-gelling extract, NE) was based on characterizing surface and interfacial tension, dispersion efficiency, mixing effects, salinity effects, stability, and droplets size distributions. We found that surface tension values follow a linear relationship with respect to the natural logarithm of the concentrations of NE. The application of NE in the water phase led to decreasing oil-water interfacial tensions. Surface tension tests were also used to quantify the effect of oil-in-water (O/W) emulsion ratios once either natural or commercialized dispersants were added. A key finding of our work is that the surface tension between typical 6% and 3% v/v O/W emulsions was significantly reduced with the addition of discrete amounts of NE. This result indicated that the dynamic balance between O/W and water-in-oil (W/O) emulsions was thermodynamically more stable toward O/W emulsion states with NE. We also found that O/W emulsions with higher dispersion effectiveness were formed for both 10 and 35 Practical Salinity Units, as the dispersant to oil ratios increased, with a significant correlation to the mixing energy. We observed that the O/W emulsions with natural dispersants had a significantly smaller weighted average diameter compared to those with COREXIT® EC9500A. Such phenomenon can be explained by understanding intermolecular interactions due to the structure and type of dispersant. In conclusion, cactus-based mucilage extracts could be used as environmentally-benign dispersants and, therefore, reduce negative social perceptions of the application of dispersants to clean up spilled oil.
Article
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This study was planned to explore the locally available natural sources of gum hydrocolloids as a natural modifier of different starch properties. Corn (CS), sweet potato (SPS), and Turkish bean (TBS) starches were mixed with locally extracted native or acetylated cactus (CG) and acacia (AG) gums at 2 and 5% replacement levels. The binary mixtures (starch–gums) were prepared in water, freeze dried, ground to powder, and stored airtight. A rapid viscoanalyzer (RVA), differential scanning calorimeter (DSC), texture analyzer, and dynamic rheometer were used to explore their pasting, thermal, textural, and rheological properties. The presence of acetylated AG or CG increased the final viscosity (FV) in all three starches when compared to starch pastes containing native gums. Plain SPS dispersion had a higher pasting temperature (PT) than CS and TBS. The addition of AG or CG increased the PT of CS, SPS, and TBS. The thermograms revealed the overall enthalpy change of the starch and gum blends: TBS > SPS > CS. The peak temperature (Tp) of starches increased with increasing gum concentration from 2 to 5% for both AG and CG native and modified gums. When compared to the control gels, the addition of 2% CG, either native or modified, reduced the syneresis of starch gels. However, further addition (5% CG) increased the gels’ syneresis. Furthermore, the syneresis for the first cycle on the fourth day was higher than the second cycle on the eighth day for all starches. The addition of native and acetylated CG reduced the hardness of starch gels at all concentrations tested. All of the starch dispersions had higher G′ than G″ values, indicating that they were more elastic and less viscous with or without the gums. The apparent viscosity of all starch gels decreased as shear was increased, with profiles indicating time-dependent thixotropic behavior. All of the starch gels, with or without gums, showed a non-Newtonian shear thinning trend in the shear stress vs. shear rate graphs. The addition of acetylated CG gum to CS resulted in a higher activation energy (Ea) than the native counterparts and the control. More specifically, starch gels with a higher gum concentration (5%) provided greater Ea than their native counterparts.
Article
BACKGROUND: Natural coagulants are used as much as possible to reduce synthetic materials that produce side effects in their use. The use of natural coagulants will be cheaper than synthetic coagulants, which are commonly used for water purification. Chinese tea seeds (Cassia angustifolia) can reduce turbidity, because they contain complex carbohydrates and sugars that can bind particles in the water. Cassia angustifolia plant may also be used as a coagulation agent for conventional drinking water treatment. AIM: This study aims to determine the optimization of coagulants from Chinese teak seed powder (Cassia angustifolia as a natural coagulant in reducing the turbidity of wells water. METHODS: This study used Cassia angustifolia coagulant for the water treatment coagulation process with turbidity and pH parameters. This was a quasi-experimental study. The Completely Randomized Design (RAL) method was used. The study location was carried out at the Laboratory of the Environmental Health Department, Poltekkes, Ministry of Health, Banda Aceh. The doses used were 10 ppm, 30 ppm, 50 ppm, 70 ppm, and 100 ppm. The data were analyzed by one-way analysis of variance (ANOVA). RESULTS: There is a difference in turbidity reduction in dug healthy water when Cassia angustifolia is added at doses of 10 ppm, 30 ppm, 50 ppm, 70 ppm, or 100 ppm. CONCLUSION: Cassia angustifolia coagulant can be used at low turbidity levels with low doses, but it is necessary to investigate the active compound content and its biocoagulant properties.
Article
Most industries in the world treat their wastewaters with a conventional coagulation-flocculation process using alum as coagulant, polyacrylamide (PAM) as flocculant and lime as coagulant aid. To reduce the use of chemical products in the process, experiments were conducted to substitute the PAM with cactus juice (CJ) as flocculant. From the obtained data, it was concluded that the substitution of PAM with CJ in the coagulation-flocculation process was very effective, compared with PAM. Depending on the wastewater's origin, the bioflocculant showed removal efficiencies of 83.3-88.7% for suspended solids (SS) and 59.1-69.1% for chemical oxygen demand (COD). Lime addition enhanced the coagulation-flocculation process in the presence of CJ similarly to the PAM with efficiencies greater than 90% for both SS and COD. The CJ powder's infrared (IR) spectrum showed the main functional groups present in PAM. It was concluded that CJ as a flocculant fits well with the definition of sustainability and it is appropriate for countries that have regions where cactuses grow naturally.
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This document is not issued to the general public and all rights are reserved by the World Health Organization. The document may not be reviewed, abstracted, quoted, reproduced or translated, in part or in whole, without the prior written permission of WHO. No part of this document may be stored in a retrieval system or transmitted in any form or by any means -electronic, mechanical or other without the prior written permission of WHO. The views expressed in documents by named authors are solely the responsibility of those authors. Foreword Around 2.2 million die of basic hygiene related diseases, like diarrhoea, every year. The great majority are children in developing countries. Interventions in hygiene, sanitation and water supply make proven contributors to controlling this disease burden. For decades, universal access to safe water and sanitation has been promoted as an essential step in reducing this preventable disease burden. Nevertheless the target of "universal access" to improved water sources and basic sanitation remains elusive. The "Millenium Declaration" established the lesser but still ambitious goal of halving the proportion of people without access to safe water by 2015. Achieving "universal access" is an important long-term goal. How to accelerate health gains against this long-term backdrop and especially amongst the most affected populations is an important challenge.
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In Mexico, the preparation of lime mortar may include the addition of nopal juice. The lime mortar prepared in this way has been used for centuries for restoring and protecting historical buildings because of an improved performance against water penetration and cracking. To date, no scientific explanation has been offered to explain the use of cactus juice in lime mortar. The objective of this study was to provide a preliminary experimental account of the use of nopal juice as an impermeabilization agent. Calcium hydroxide and commercial slaked-lime pastes were prepared and mixed with varying concentrations of nopal juice at ratios of 0.65%, 1% and 1.95% of cactus juice to Ca(OH)2 or commercial slaked lime. The dry pastes thus obtained were evaluated by a penetration-breaking test with a TA-XT2 texture analyzer. Increasing amounts of cactus juice in the formulation resulted in a drastic reduction of the maximum stress and deformation values of the pastes as compared to those of the control sample. In the control sample, a more mechanically homogeneous Ca(OH)2 structure was formed. In the sample with the lower cactus juice ratio, the mucilage had a reduction effect upon the continuity of the network. The amorphous soft filler, forming a discontinuous phase, makes the hydroxide network weaker. As the ratio increased, mechanical properties also increased due to the formation of a homogeneous network of nopal mucilage interpenetrated into the hydroxide base. Results indicate the formation of an interpenetrated network of nopal mucilage with no structural modification involved.
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The use of natural environmentally benign agents in the treatment of drinking water is rapidly gaining interest due to their inherently renewable character and low toxicity. We show that the common Mexican cactus produces a gum-like substance, cactus mucilage, which shows excellent flocculating abilities and is an economically viable alternative for low-income communities. Cactus mucilage is a neutral mixture of approximately 55 high-molecular weight sugar residues composed basically of arabinose, galactose, rhamnose, xylose, and galacturonic acid. We show how this natural product was characterized for its use as a flocculating agent. Our results show the mucilage efficiency for reducing arsenic and particulates from drinking water as determined by light scattering, Atomic Absorption and Hydride Generation-Atomic Fluorescence Spectroscopy. Flocculation studies proved the mucilage to be a much faster flocculating agent when compared to Al2(SO4)3 with the efficiency increasing with mucilage concentration. Jar tests revealed that lower concentrations of mucilage provided the optimal effectiveness for supernatant clarity, an important factor in determining the potability of water. Initial filter results with the mucilage embedded in a silica matrix prove the feasibility of applying this technology as a method for heavy metal removal. This project provides fundamental, quantitative insights into the necessary and minimum requirements for natural flocculating agents that are innovative, environmentally benign, and cost-effective.
Article
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Two distinctive water-soluble high-molecular-weight pectic polysaccharide materials that occur in Opuntia cladodes and fruits have been extracted and studied in their chemical and rheological properties in our laboratory, namely, the well-known mucilage and a calcium-sensitive gelling fraction. Mucilage is present in the characteristic slimy fluid secreted by cladodes and fruits and it does not gel in the presence of calcium. Pectin of low degree of methoxyl occurs in the cell wall and can be extracted using a mild alkali process aided with a chelating agent. It shows remarkably good gelling properties in the presence of CaCl 2 by a cooperative Ca 2+ "egg-box" binding mechanism. Although both materials share similarities in the composition profile of their neutral constituent sugar residues, pectin has a significantly greater amount of linear polygalacturonic acid. This difference causes very different physicochemical and functional properties underlying the potential applications of these polysaccharides in a wide variety of fields (e.g., foods, biotechnology, medicine).
Article
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The rheological properties of aqueous solutions of the mucilage isolated from Opuntia ficus indica have been examined. Steady-shear viscosities in a range of shear rate from 1 to 300 s−1 were observed as a function of mucilage concentration, temperature, pH and ionic strength. A non-Newtonian shear-thinning behavior was observed. A quite important increase in pseudoplasticity (or shear thinning) due to increase in the mucilage concentration, in the range from 1 to 10% (w/w) was showed. In the range of shear rates examined, viscosity values of a mucilage solution at 10% are similar to those shown by a xanthan 3% aqueous solution, both at 25°C. The Ostwald–de Waele or power law model successfully correlated the viscosity–shear rate data. The viscosity was dependent on ionic strength, as in the case of polyelectrolytes, and decreased with ionic strength. This behavior was more pronounced when using divalent cations. A marked dependence of viscosity on pH was also observed, as pH was increased from acidic to alkaline conditions, the viscosity increased.
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To investigate the association between drinking water quality and gastrointestinal illness in the elderly of Philadelphia. Within the general population, children and the elderly are at highest risk for gastrointestinal disease. This study investigates the potential association between daily fluctuations in drinking water turbidity and subsequent hospital admissions for gastrointestinal illness of elderly persons, controlling for time trends, seasonal patterns, and temperature using Poisson regression analysis. All residents of Philadelphia aged 65 and older in 1992-1993 were studied through their MEDICARE records. For Philadelphia's population aged 65 and older, we found water quality 9 to 11 days before the visit was associated with hospital admissions for gastrointestinal illness, with an interquartile range increase in turbidity being associated with a 9% increase (95% CI 5.3%, 12.7%). In the Belmont service area, there was also an association evident at a lag of 4 to 6 days (9.1% increase, 95% CI 5.2, 13.3). Both associations were stronger in those over 75 than in the population aged 65-74. This association occurred in a filtered water supply in compliance with US standards. Elderly residents of Philadelphia remain at risk of waterborne gastrointestinal illness under current water treatment practices. Hospitalisations represent a very small percentage of total morbidity.
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Excessive levels of arsenic in drinking water is a vast health problem in Southeast Asia. Several viable approaches to mitigation could drastically reduce arsenic exposure, but they all require periodic testing.
Article
Analytical methods were developed to accurately determine the levels of the most prevalent trace metal contaminants in a variety of alum feedstocks used in the coagulation process of drinking water treatment, A combination of chelation ion chromatography, chelation extraction-atomic absorption spectrometry, and hydride generation atomic fluorescence allowed for the selective isolation of trace metals from the alum matrix with a high degree of precision and sensitivity. Trace levels of arsenic, cadmium, chromium, copper, manganese, nickel, lead, and zinc were found in the range of 20-330 mug/g aluminum (Al); iron, recognized as a co-contaminant in the raw material, was present at 20 mg/g Al. By extrapolating these measured levels to an upper yet realistic applied dosage of alum in drinking water treatment, the authors could predict the contaminants' concentrations (under a worst-case scenario) in both the finished water and alum sludge. For finished water even if it was assumed that none of the trace metals was removed during coagulation, the contaminants' concentrations did not exceed drinking water standards, and their contribution reached only a small fraction of the permitted maximum contaminant level. in a scenario in which the trace metals were assumed to be removed during the coagulation process, levels that would accumulate in the alum sludge would not be significant enough to heavily influence decisions to apply alum sludge to land for agricultural uses.
Article
Two different concentrations (aprox. 6 and 12%) and two presentations (raw and cooked) of dehidrated nopal were fed to laboratory rats and growth and serum total cholesterol, lipoprotein profile and glucose determined. Samples of raw and cooked nopal were chemically characterized for moisture, protein, ash, crude fiber, ether extract, total dietary fiber, reducing sugars, amino acids, minerals and gross energy. Cooking slightly affected some of the nutrients analyzed. After one month feeding, blood was withdrawn via intracardiac puncture and serum glucose, total cholesterol, HDL, LDL, and VLDL were determined. Rats fed 12% nopal had lower weight gains (P<0.05) when compared with counterparts fed 6% nopal or the control diet. Consumption of nopal did not affect (P>0.05) glucose, total cholesterol and HDL cholesterol levels. However, rats fed raw nopal at the 12% concentration level had a 34% reduction in LDL cholesterol levels; thus, it was concluded that raw nopal had a potentially beneficial effect for hypercholesterolemic individuals.
Article
The mucilage extracted from the cladodes (modified stems) of Opuntia ficus-indica contains residues of d-galactose, d-xylose, l-arabinose, l-rhamnose, and d-galacturonic acid. Seasonal variation in the sugar composition of the mucilage has been investigated. Fractionation studies indicate that the mucilage is essentially homogeneous. The rate of release of the constituent sugars and the change in optical rotation on mild hydrolysis coupled with the results of chromic acid oxidation suggest that the mucilage contains α-arabinofuranosyl, β-xylopyranosyl, β-rhamnopyranosyl, β-galactopyranosyl, and α-galactopyranosyluronic acid residues. The results also suggest a core containing galacturonic acid, rhamnose, and galactose, to which xylose and arabinose are attached in peripheral positions.
Article
Performing jar tests often requires carrying out a time consuming iteration procedure to find out the right amount of chemical for coagulation–flocculation process in water treatment plants. Applying the response surface method (RSM) in jar tests as an alternative to the conventional methods was investigated in this study. The purpose is finding out the optimum combination of coagulant dose and pH with respect to the highest removal efficiency of turbidity and dissolved organic carbon (DOC). The results achieved using poly-aluminum chloride (PACl) were compared to those achieved using conventional coagulant such as alum. The quadratic models developed for the two responses (turbidity removal and DOC removal) indicated that the optimum conditions to be PACl concentration of 0.11mM at pH 7.4 and alum concentration of 0.15mM at pH 6.6. Compromising to simultaneously optimize the two responses resulted in 91.4% turbidity removal and 31.2% DOC removal using PACl whereas 86.3% turbidity and 34.3% DOC were removed using alum. Confirmation of experimental results was found to be close to the prediction derived from the models. This demonstrates the benefits of the approach based on the RSM in achieving good predictions while minimizing the number of required experiments.
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This report was prepared by the Working Group on Waterborne Cryptosporidiosis (Technical Task Force E, Developmental Status of Environmental Sampling, Water Testing, and Surrogate Indicators). Methods for detecting Cryptosporidium oocysts in water have centered around microscopic examination of fluorescent antibody-stained concentrates from large-volume water samples. The limitations of these antibody-based methods include the need for experienced analysts, lengthy analytical time, expense, lack of specificity, erratic efficiency, low precision, and difficulty in determining viability. A number of methods, assays, and procedures that have the potential for ameliorating some of these limitations are currently being evaluated. How successful such processes will be remains to be demonstrated by the scientific community.
Article
Hydrocolloids are water-soluble biopolymers consisting of high molecular weight polysaccharides. For generations, these biopolymers were also termed gums or stabilizers imparting viscosity, gelification and long-term stability to food systems.Some hydrocolloids were also considered as emulsifying agents, since they help to form and stabilize oil-in-water emulsions. Only in the last two decades questions have been raised as to the mode of their action in low viscosity and low concentrations dispersed systems consisting of oil and water.Gum Arabic is the only gum in use in dilute emulsion systems which was proved to be a good emulsifier - adsorbing onto oil-water interfaces and imparting steric stabilization.However, other gums have been known to reduce surface and interfacial tensions, to adsorb onto solid surfaces and to improve stability of oil-in-water emulsions. Only recently attention has been paid to the structure-surface activity relationship between the gums and their emulsification abilities. Galactomannans, xanthans, pectins, etc. are being considered as emulsifying agents, and correlation between their internal composition and activity are being studied.This review will discuss the drawbacks and prospects of hydrocolloids as food emulsifying agents, as native hydrocolloids and as modified (chemically, enzymatically) macrobiopolymeric amphiphiles.
Article
The water soluble fraction of peeled prickly pear nopals called native sample (NS) has been characterised mainly by SEC/MALLS analysis. Two main components have been identified: one with high average molar mass (Mw of 13×106gmol−1) called the high weight sample (HWS), the other being a low Mw fraction (LWS). After extensive ultra filtration of NS, isolated HWS and LWS are obtained. From sugar composition analysis, HWS has been found to be a pure polysaccharide, without protein of the pectin family. Moreover, HWS contains a low amount of charged sugar. The conformation of HWS has been discussed using molar masses, gyration radii and viscometry results and LWS has been evidenced as a protein. Rheological behaviour is reported to give an initial understanding of the system's behaviour. The effect of the degree and purification and added monovalent and divalent salts were investigated, The low charge density of the polymer backbone resulted in interesting viscosity stability even in the presence of salts.
Article
The use of fenugreek mucilage, a natural polysaccharide and a direct food additive, as a flocculating agent for removal of suspended and dissolved solids from sewage effluent has been reported. A flocculation study has been done by the standard jar test method. The percent removal of suspended solid (SS) and dissolved solid (TDS) was determined by varying the polymer dose, pH and contact time. X-ray diffraction patterns of the solid waste material of mucilage and flocs (so obtained after treatment) were used to suggest the incorporation of the crystalline waste material in the mucilage. The optimal mucilage concentration was found to be 0.16 mg/l. The suitable pH range for maximum solid removal (SS and TDS) was alkaline and the time required for treatment was 1-3 h.
Article
The city of Durham, N.C., performed full-scale testing of alum recovery from alum sludge generated in a 22-mgd water treatment plant. Purposes of the tests were to determine the technical feasibility of mechanical dewatering of acidified alum solids and to develop design data. Three mechanical dewatering devices - a belt press, a centrifuge and a diaphragm filter press - were screened in bench-scale tests. The belt press did not warrant further testing. Manufacturers of the centrifuge and the filter press then conducted dewatering tests at the treatment plant. Tests showed that with proper chemical conditioning, both devices could be successfully used to dewater acidified solids to 30 percent or more. Recovered alum is proposed for two uses in Durham: as a coagulant in the water plant and as a phosphorus-removal chemical in one of the city's wastewater treatment plants. Recovering and recycling alum can significantly lower final sludge disposal costs, which are increasing as more restrictive solid waste regulations take effect.
Article
Graft copolymers of starch, amylose, and amylopectin with polyacrylamide have been synthesized using a ceric-ion-initiated solution polymerization technique. In the case of amylopectin-g-polyacrylamide (Ap-g-PAM), four graft copolymers have been synthesized with variation in the number and length of grafted polyacrylamide chains. The flocculation behavior has been studied in a 0.25% kaolin suspension. It has been found that among the three graft copolymers of the starch family, Ap-g-PAM is the best flocculating agent compared to starch-g-polyacrylamide (St-g-PAM) and amylose-g-polyacrylamide (Am-g-PAM). Among the series of Ap-g-PAM, the one with fewer but longer polyacrylamide chains has been found to be the most effective flocculant. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1721–1729, 1997
Article
The consumption of high levels of fibres can induce a decrease in both food digestibility and nutrient availability. Prickly pear is a pectin-rich fruit and it is possible to use it to decrease plasma cholesterol levels. Its effect on food digestibility deserves attention. This effect was determined by using a mixture of a constant quantity of casein and an increasing quantity (10, 20, 25% of the casein) of prickly pear pulp, skin and seed. In parallel, the effect of similar mixtures of carrageenan, gum arabic, locust bean gum, alginic acid and citrus pectin with casein was also studied. The flow behaviour of the different mixtures was determined and their digestibilities were measured using an in vitro digestion cell device. The apparent viscosities of the mixtures with prickly pear components and gum arabic were similar. The nature and level of fibres in the diet modified nitrogen release in the in vitro digestion cell model. The pulp of the prickly pear decreased the digestibility of the casein-based diet to a greater extent than the other soluble fibres, whatever the percentage used. The results suggest that the decrease in N release in the digestion cell model is due to the interaction of the fibres with the enzymes or casein rather than to the apparent viscosity of the mixtures.© 2000 Society of Chemical Industry
Article
Water is a scare commodity now. Recycling of municipal wastewater, industrial and mineral processing effluents require treatment with the inorganic or organic flocculants. Inorganic flocculants are used in large quantities, leave large amount of sludge and are very much affected by pH changes. Other polymeric flocculants are used in a very minute quantity, form large cohesive floc and are inert to pH changes. Both natural and synthetic polymers are used as flocculants. Natural polymers are biodegradable and are effective at very large dosages but are very shear stable. The synthetic polymers are highly effective flocculants at very small dosages and have high tailorability, but have poor shear stability. In the authors laboratory, a new class of flocculants has been developed by grafting polyacrylamide branches onto polysaccharide such as guargum, hydroxypropyl guargum, starch, amylopectin and sodium alginate. These grafted polysaccharides exhibit synergistic flocculation characteristics, shear stability and controlled biodegradability. Out of all the grafted polysaccharides, amylopectin grafted polysaccharides out performs most of the commercially available flocculants. The polacrylamide branches grafted on high molecular weight branched amylopectin have larger approachability to contaminants in the industrial effluents [1, 2].
Article
Opuntia genus is widely known for its mucilage production. Mucilage, a complex carbohydrate with a great capacity to absorb water, should be considered a potential source of industrial hydrocolloid. Mucilage contains varying proportions of l-arabinose, d-galactose, l-rhamnose, and d-xylose, as well as galacturonic acid. The mucilage content found in the cactus cladodes is influenced not only by the management of the crop but is also dependent on the temperature, irrigation and the rain.In some countries, small farmers use cactus mucilage to purify drinking water. Another traditional use is for improving house paint. Recently, a cactus cladode extract was tested to improve water infiltration in soils.Other properties of cactus mucilage, particularity culinary uses, have also been mentioned.
Article
The mucilage isolated from Opuntia is shown to contain arabinose, galactose, galacturonic acid, rhamnose and xylose. It has a uronic acid content of ca 10% and a MW of 4.3 × 106. It equilibrates to 175% of its dry wt at 100% relative humidity. Its possible role in the physiology of the plant is discussed.
Article
Fully de-esterified pectin with excellent gelling properties was isolated in the sodium-salt form from fresh ‘nopal’ cactus (Opuntia ficus indica) pads (0.6% w/w yield of fresh weight) using an alkaline extraction medium in the presence of a sequestering agent. Sugars composition of the cactus pectin alkaline extract (CPAE) was: 85.4% uronic acids, 7.0% galactose, 6.0% arabinose and minor quantities of rhamnose and xylose. Features of the Fourier-transformed infrared spectrum were nearly identical to those of commercial citrus pectin as well as to homogalacturan-rich pectin isolated from prickly pear, lime peel, and sugar beet pulp. The gelling behavior of this material was studied as a function of amount of Ca2+ added and temperature by dynamic oscillatory rheology. Addition of Ca2+ at 85 °C was adjusted at varying stoichiometric ratios, R (=2 [Ca2+]/[COO−]), namely 0.07, 0.21, 0.35 and 0.42 and fixed pectin concentration (16 g/L), and a temperature dependent behavior of the system on cooling was imposed. Evolution of the viscoelastic storage (G′) and loss (G′′ moduli on cooling revealed unequivocal set up of a gel network under a highly cooperative sol-gel transition at R ⩽ 0.21. At greater R values, the Ca2+-mediated dimeric association of pectin chains led to formation of a gel network even at 85 °C. On heating, pectin gels melted partially at temperatures notably greater than those at which they were formed. Thermal hysteresis observed between the cooling and heating temperature traces is explained in terms of helix–helix aggregation. The gelling behavior of this system is interpreted in terms of the formation of two distinct types of junctions mediated by the stoichiometric amount of calcium (R). Namely, short ‘egg-box’ type junctions formed directly at high temperature on addition of calcium (limited zones are related to high mobility of the chains) and highly cooperative 21 helix junctions followed by aggregation formed at lower temperature under a thermal conformational transition driven by charge neutralization and lower chain mobility (related to stabilization by H-bonds).
Article
Mechanisms of coagulation have been widely investigated by many researchers. Little is understood about the critical role of rapid-mixing in water treatment. In this study, a photometric dispersion analyzer (PDA) was employed to monitor clay coagulation by alum and polymeric aluminum chloride (PACl). The effect of rapid-mixing time on particle removal was studied. A standard jar test was performed to determine the degree of destabilization of particles. Maximum ratio outputs of PDA measurements were inversely related to residual turbidities. Adequate rapid-mixing times evaluated from both PDA and mixing tests were close to each other. Studies of coagulation mechanisms at various rapid-mixing times indicated that mixing time had significant impact on charge neutralization and sweep coagulation. The difference in residual turbidity can be attributed to the characteristics of microflocs. The rise in residual turbidity in sweep coagulation suggested the breakage of microflocs.
Article
Prickly pear pectin intake decreases plasma LDL concentrations by increasing hepatic apolipoprotein B/E receptor expression in guinea pigs fed a hypercholesterolemic diet. To investigate whether prickly pear pectin has an effect on cholesterol absorption and on enzymes responsible for hepatic cholesterol homeostasis, guinea pigs were fed one of three semipurified diets, each containing 15 g lard/100 g diet: 1) the lard-basal diet with no added cholesterol or prickly pear pectin (LB diet); 2) the LB diet with 0.25 g added cholesterol/100 g diet (LC diet); or 3) the LC diet containing 2.5 g prickly pear pectin/100 g diet, added at the expense of cellulose (LC-P diet). Animals fed the LB diet had the lowest plasma LDL and hepatic cholesterol concentrations, followed by animals fed the LC-P diet (P < 0.001). Hepatic 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) reductase activity was highest in the group fed the LB diet, with similar values for animals in the other two groups. A positive correlation existed between plasma LDL cholesterol concentration and hepatic acyl CoA:cholesterol acyltransferase activity (r = 0.87, P < 0.001). Cholesterol absorption was not different among the three dietary groups. These results indicate that the decreased plasma and hepatic cholesterol concentrations of animals fed prickly pear pectin are not explained by differences in cholesterol absorption but rather are due to mechanisms that alter hepatic cholesterol homeostasis, resulting in lower plasma LDL concentrations.
Article
The proximate composition of pulp, skin and seeds of prickly pear cactus (Opuntia ficus indica) was investigated and is reported on a dry weight basis. The most abundant component of the pulp and skin was ethanol-soluble carbohydrates. Pulp contained glucose (35%) and fructose (29%) while the skin contained essentially glucose (21%). Protein content was 5.1% (pulp), 8.3% (skin) and 11.8% (seeds). Starch was found in each of the three parts of the fruit. Pulp fibers were rich in pectin (14.4%), skin and seeds were rich in cellulose (29.1 and 45.1%, respectively). Skin was remarkable for its content of calcium (2.09%) and potassium (3.4%). Prickly pear is a neglected nutritional source which should be more widely used because of its potential nutrient contribution.
Article
This article is the first one in a series dedicated to the study of hyaluronan as observed by IR spectrometry. The goal is to determine its hydration mechanism and the structural changes this mechanism implies. Hyaluronan is a natural polysaccharide that is widely used in biomedical applications and cosmetics. Its macroscopic properties are significantly dependent on its degree of hydration. In this article we record the IR spectrum of a several micron thick dried film and deduce that four or five residual H(2)O molecules remain around each disaccharide repeat unit in the dried film. We then compare the spectra of sodium hyaluronan and its acid form to assign vibrational bands linked to the carboxylate group. We proceed with a qualitative analysis of the spectral changes induced by changes of temperature and hygroscopicity, two independent parameters that act by modifying the hydrogen bond network of the sample. This enables us to assign most of the vibrational bands of the hydrophilic groups and to distinguish the bands that are due to these hydrophilic groups when they are or are not hydrogen bonded. It constitutes a prerequisite for the quantitative analysis of hydration spectra that will be described in the following articles of this series.
Article
Opuntia ficus indica cladodes are used in traditional medicine of many countries for their cicatrisant activity. The major components of cladodes are carbohydrate-containing polymers, which consist of a mixture of mucilage and pectin. In this paper we studied the cytoprotective effects of cladodes on experimental ethanol-induced ulcer in rat. The O. ficus indica cladodes administration gives rise to cytoprotection phenomena by breaking up the epithelial cells and stimulating an increase in mucus production. When O. ficus indica cladodes are administered as a preventive therapy, keep the gastric mucosa under normal condition by preventing mucus dissolution caused by ethanol and favouring mucus production. An increase of mucus production is also observed during the course of the curative treatment. The treatment with O. ficus indica cladodes provokes an increase in the number of secretory cells. Probably, the gastric fibroblasts are involved in the antiulcer activity.
Article
A bioflocculant, MBFA9, was produced from a strain of bioflocculant-producing bacteria isolated from a soil sample and identified as Bacillus mucilaginosus. MBFA9 had a good flocculating capability and could achieve a flocculating rate of 99.6% for kaolin suspension at a dosage of only 0.1 ml/l. The major component of MBFA9 was found to be polysaccharide composed mainly of uronic acid (19.1%), neutral sugar (47.4%) and amino sugar (2.7%). Infrared spectrum analysis showed the presence of carboxyl and hydroxyl groups in the bioflocculant. MBFA9 is nontoxic and can be used in food industries for suspended solids (SS) recovery. When applied to starch wastewater treatment, MBFA9 greatly accelerated the formation of flocs and the settling of organic particles in the presence of Ca(2+) salt. After 5 min of settling, the removal rate of SS and chemical oxygen demand were up to 85.5% and 68.5%, respectively, which is better than traditional chemical flocculants.
 Time requirement for rapidmixing in coagulation
  • C Kan
  • C Huang
  • J R Pan
Kan, C., Huang, C. & Pan, J. R.  Time requirement for rapidmixing in coagulation. Colloids and Surfaces A: Physiochemical and Engineering Aspects 203 (1-3), 1-9.
 Introduction to Macromolecular Science
  • P Munk
  • T M Aminabhavi
Munk, P. & Aminabhavi, T. M.  Introduction to Macromolecular Science. Wiley-Interscience, New York, pp. 609.
 Organic materials
  • R A Nyquist
  • R O Kagel
Nyquist, R. A. & Kagel, R. O.  Organic materials. In: Infrared and Raman Spectroscopy (E. G. Brame & J. G. Grasselli, eds.). Marcel Dekker, Inc., New York, pp. 442-565.