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Extraction and purification of d-limonene from orange peel wastes: Recent advances

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Abstract

Orange peel wastes, with an estimated global annual production of 25 million tonnes, are problematic to dispose of but can be used to obtain a range of valuable products, among them the main constituent of orange essential oil, d-limonene (DL). This review aims to layout recent advances in the field of DL extraction and purification. Besides substitution of the conventional solvent hexane with certain bio-based solvents, a range of techniques are presented. These include enhanced solvent extraction processes through temperature and pressure intensification or ultrasound, improved distillation most commonly using different microwave-based techniques but also enzymes, and supercritical CO2 extraction. Even though purification has been found to be the most energy-intensive and environmentally impacting step, most studies did not improve on existing centrifugation, decantation, or fractional distillation methods. Chromatography has been proven effective at obtaining high DL purities; however, it still has to be improved because of its high costs and low productivity.

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... The use of limonene as solvent offers the benefit of lower toxicity, flammability, and environmental risk as compared to conventional solvents, such as n-hexane (Bertouche et al., 2013;. The high hydrophobicity makes it very suitable to be used as a solvent in lipids extraction (Siddiqui et al., 2022) and, its use can provide higher vegetable oil yields in extraction processes over hexane, due to its slightly polar nature and greater ability to dissolve triacylglycerols, since it is necessary to use higher extraction temperature to boil it, giving the extract a lower viscosity and providing a higher rate of oil diffusion in the matrix (Liu and Mamidipally, 2005;Mamidipally and Liu, 2004). ...
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Chapter
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BACKGROUND D‐limonene, a high‐value added molecule found in the flavedo of orange peels (about 0.7% w/w), is used in the nutritional, pharmaceutical and cosmetic fields. An accelerated moderate temperature extraction was investigated in order to recover D‐limonene. Furthermore, the residue from the extraction was used for energy recovery through the pyrolysis process. RESULTS The proposed extractive process was able to recover D‐limonene up to 0.48 ± 0.002% w/w (on a wet basis) from orange peels at the highest investigated temperature (130 °C for 60 min). The residual matrix was then subjected to a dehydration step, which was carried out at room temperature for 10 days, in order to decrease the moisture from the porous surface, and then to a pyrolysis process. The average chemical energy recovery efficiency (91% ± 0.04) suggested that the thermochemical process is suitable for biofuel production. CONCLUSION Orange peels can be exploited for the recovery of an important bio‐product and the residue can be used as feedstock for biofuels. This work has confirmed that accelerated extraction is more efficient than Soxhlet extraction (more than 68% w/w against 37% w/w of total D‐limonene, respectively), and that a pyrolysis process can be successfully performed on the residue. © 2016 Society of Chemical Industry
Article
The citrus peels and residue of fruit juices production are rich in d-limonene, a cyclic terpene characterized by antimicrobial activity, which could hamper energy valorization bioprocess. Considering that limonene is used in nutritional, pharmaceutical and cosmetic fields, citrus by-products processing appear to be a suitable feedstock either for high value product recovery or energy bio-processes. This waste stream, more than 10MTon at 2013 in European Union (AIJN, 2014), can be considered appealing, from the view point of conducting a key study on limonene recovery, as its content of about 1%w/w of high value-added molecule. Different processes are currently being studied to recover or remove limonene from citrus peel to both prevent pollution and energy resources recovery. The present review is aimed to highlight pros and contras of different approaches suggesting an energy sustainability criterion to select the most effective one for materials and energy valorization.
Article
The objective of this study was to analyze the anaerobic digestion process inhibition by limonene, the main component of citrus essential oils (CEO) present in citrus peel. The biochemical methane potential (BMP) values of the citrus waste tested (orange peel, mandarin peel, mandarin pulp and rotten fruit) were 354-398LCH4kgVS-1. Grinding the orange peel (2.5glimoneneL-1) did not influence the BMP values, but slowed the kinetics, due to the increased availability of CEO caused by the grinding. The effect of (R)-limonene (0-3000mgL-1) on the batch anaerobic digestion of microcrystalline cellulose was also assessed. The half maximal inhibitory concentration, IC50, was 423mgkg-1 in an initial run and 669mgkg-1 in a second run of batch experiments. The methane course and IC50 values indicate that there are reversible inhibition and biomass activity recovery during the anaerobic digestion process, despite the non-reversible antimicrobial mechanism described in the literature for limonene to date.
Article
Citrus fruit peels and leaves have always been the imperative attention of different researchers in pharmaceutical and cosmeceutical field. Moreover, the aroma of essential oil gains good reputation in aromatherapy. The volatile oil from leaves and rind of the citrus fruit has been reported by Hydrodistillation and expression methods several times. At this time, in present study, extraction of volatile oil forms the leaves and peels of fruit from citrus plants were obtained by hydrodistillation. Total seven Citrus plants Citrus lemon, Citrus medica, Citrus aurantium, Citrus pseudolemon, Citrus sinensis, Citrus reticulate and Citrus maxima were selected here for extraction. The percentage yield so obtained was compared.
Chapter
This chapter presents a complete picture of current knowledge on a ­useful and green biosolvent “d-limonene” obtained from citrus peels through a steam ­distillation procedure followed by a deterpenation process. Limonene is a substitute for petroleum solvents such as dichloromethane, toluene, or hexane for the extraction of natural products. This chapter provides the necessary theoretical background and some details about extraction using limonene, the techniques, the mechanism, some applications, and environmental impacts. The main benefits are decreases in extraction times, the amount of energy used, solvents recycled, and CO2 emissions.
Article
In this study, non-polar and polar compounds from coriander (Coriandrum sativum L.) seeds (CS) were fractionated using modern extraction techniques. CS were fractionated on non-polar fraction using supercritical fluid extraction (SFE) and influence of mean particle size on yield and chemical profile was investigated. Results were compared with conventional techniques used in essential oil isolation. It has been shown that SFE has certain advantages comparing to traditional techniques in terms of extraction yield and selectivity, since it provided highest linalool content (877.07 mg/100 g CS). Raffinate exhausted by SFE could be suitable for further processing, and it was subjected to ultrasound-assisted extraction (UAE) of moderately polar and polar fraction of polyphenolic compounds. Results showed that ethanolic extracts had higher antioxidant activity than water extracts for all CS mean particle sizes. The highest content of hydroxicinammic acids was observed in ethanolic extracts obtained from exhausted CS with lowest mean particle size. Therefore, coriander seeds, which have been known for its rich essential oil content, could be used for sequential production of polyphenolic-rich extracts with high antioxidant activity.
Article
(+)-Limonene is a renewable chemical with numerous and growing applications. Traditional uses such as flavor, fragrance and green solvent are rapidly expanding to include its utilization as a platform chemical, extraction solvent for natural products and active agent for functionalized products. Said constant demand expansion will feed back into rising production and use of this relevant natural product, especially for advanced applications.
Article
Second cooling was added to the oil collectors of an improved Clevenger type apparatus (ICT) to investigate the thermal reaction of essential oils from orange peel comparing to traditional Clevenger type apparatus (CT). The results demonstrated the yield rate of essential oil from ICT was significantly higher (p < 0.05) than that from CT. The major components of the essential oils consisted of monoterpenes, such as d-limonene, β-myrcene, β-pinene,γ-terpinene, α-pinene, and etc. Interestingly, we found that ICT prevented the thermal reaction-the transformation of β-myrcene to β-thujene and, reduced the oxidation on α-pinene and β-pinene of the essential oil in comparison to CT. In addition, the yield rate of γ-terpinene can also be improved via ICT comparing to CT. Thus, ICT is an effective improvement to traditional CT.
Article
A certain combination of natural products in the solid state becomes liquid, so called natural deep eutectic solvents (NADES). Recently, they have been considered promising new green solvents for foods, cosmetics and pharmaceuticals due to their unique solvent power which can dissolve many non-water-soluble compounds and their low toxicity. However, in addition to the features as solvents, the stabilisation ability of NADES for compounds is important for their further applications. In the study, the stability analysis demonstrates that natural pigments from safflower are more stable in sugar-based NADES than in water or 40% ethanol solution. Notably, the stabilisation capacity of NADES can be adjusted by reducing water content with increasing viscosity. The strong stabilisation ability is due to the formation of strong hydrogen bonding interactions between solutes and NADES molecules. The stabilising ability of NADES for phenolic compounds shows great promise for their applications in food, cosmetic and pharmaceutical industries.
Article
Citrus by-products are the processing wastes generated after citrus juice extraction and constitute about 50 % of fresh fruit weight. This solid residue comprised of peel (flavedo and albedo), pulp (juice sac residue), rag (membranes and cores) and seeds. The disposal of the fresh peels is becoming a major problem to many factories. Usually, citrus juice industries dry the residue and it is either sold as raw material for pectin extraction or pelletized for animal feeding, though none of these processes is very profitable. This residual material is a poor animal feed supplement because of its extremely low protein content and high amount of sugar. The application of agroindustrial by-products in bioprocesses offers a wide range of alternative substrates, thus helping solve pollution problems related to their disposal. This article reviews attempts that have been made to use citrus by-products to generate several value-added products, such as essential oils, pectin, enzymes, single cell protein, natural antioxidants, ethanol, organic acids, and prebiotics.
Article
The application of steam explosion and enzymatic hydrolysis pretreatments on lemon (Citrus limon L.) citrus peel wastes was studied to obtain bioethanol, galacturonic acid and other co-products, such as d-limonene and citrus pulp pellets. Steam explosion pretreatment and recovery of lemon citrus essential oils was carried out at pilot plant scale. The effect of steam explosion on lignocellulosic composition of lemon peel wastes was studied by thermogravimetric analysis. The antimicrobial activity of lemon essential oil on Saccharomyces cerevisiae and its influence on ethanol production during fermentation were also studied. The steam-exploded lemon peel wastes were processed by sequential and simultaneous hydrolysis and fermentation. Concentrations of sugars, galacturonic acid and ethanol were analyzed to measure the efficiency of these processes. Significant antimicrobial activity of lemon essential oils has been observed on S. cerevisiae at concentrations above 0.025%. The steam explosion pretreatment has shown an interesting effect on lemon peel wastes processing for obtaining ethanol and galacturonic acid. This pretreatment reduces the residual content of essential oils below 0.025% and significantly decreases the hydrolytic enzyme requirements. Ethanol production in excess of 60 L/1000 kg fresh lemon peel biomass can be obtained.
Book
Perfume Engineering is a must-have reference for engineers who design any products that require fragrances, such as perfumes, cosmetics, healthcare and cleaning products. This book provides the reader with practical guidance on perfume design, performance and classification, from its beginnings as a liquid mixture to the vapour phase, by way of odorant dispersion and olfactory perception. It does this through the application of development and validation models to account for fragrance evaporation, propagation and perception.
Article
Cold-pressed fruit peel essential oils of two cultivars of sweet orange (Citrus sinensis (L.) Osbeck), Valencia and Hamlin, from Ethiopia were analyzed by capillary GC and GC–MS, without prior separation, and compared with each other. On two different GC columns, 58 components representing an average of 99.9% of the total volatile fraction were positively identified. Trans-carveol was proved for the first time as one of the components in cold-pressed orange oils. Monoterpene hydrocarbons followed by aldehydes and alcohols were the predominate quantitative composition of the volatile part in both the Valencia and Hamlin oils. Their percentage compositions, respectively, were 98.61% and 99.14% in total monoterpene hydrocarbons, 0.76% and 0.49% in aliphatic and terpenic aldehydes, and 0.47% and 0.18% in total alcohol concentration. In the cold-pressed oil of Valencia, oxygenated volatiles amounted to 1.26%, while in Hamlin amounted to only 0.70%. Compared to the same cultivars recently reported from other countries, high concentration of neral (0.09%) and geranial (0.16%) were found in Valencia orange oil. The major aliphatic aldehydes quantified in both oils are n-octanal and n-decanal, which are especially important character-impact constituents of sweet orange oils. Values for individual components like n-octanal, n-decanal and linalol were above, below or within values reported earlier. Copyright © 2000 John Wiley & Sons, Ltd.
Article
d-Limonene, a major constituent of citrus oils, is a monoterpene widely used as a flavor/fragrance additive in cosmetics, foods, and industrial solvents as it possesses a pleasant lemon-like odor. d-Limonene has been designated as a chemical with low toxicity based upon lethal dose (LD50) and repeated-dose toxicity studies when administered orally to animals. However, skin irritation or sensitizing potential was reported following widespread use of this agent in various consumer products. In experimental animals and humans, oxidation products or metabolites of d-limonene were shown to act as skin irritants. Carcinogenic effects have also been observed in male rats, but the mode of action (MOA) is considered irrelevant for humans as the protein α2u-globulin responsible for this effect in rodents is absent in humans. Thus, the liver was identified as a critical target organ following oral administration of d-limonene. Other than the adverse dermal effects noted in humans, other notable toxic effects of d-limonene have not been reported. The reference dose (RfD), the no-observed-adverse-effect level (NOAEL), and the systemic exposure dose (SED) were determined and found to be 2.5 mg/kg/d, 250 mg/kg//d, and 1.48 mg/kg/d, respectively. Consequently, the margin of exposure (MOE = NOAEL/SED) of 169 was derived based upon the data, and the hazard index (HI = SED/RfD) for d-limonene is 0.592. Taking into consideration conservative estimation, d-limonene appears to exert no serious risk for human exposure. Based on adverse effects and risk assessments, d-limonene may be regarded as a safe ingredient. However, the potential occurrence of skin irritation necessitates regulation of this chemical as an ingredient in cosmetics. In conclusion, the use of d-limonene in cosmetics is safe under the current regulatory guidelines for cosmetics.
Article
The physicochemical indices and the qualitative and quantitative composition of the volatile fraction and the oxygenated heterocyclic fraction of cold-pressed Key lime oil (types A and B) and Persian lime oil are reported. The volatile fraction of Persian lime oil is characterized by a higher content of limonene, γ-terpinene, esters, and monoterpene aldehydes and a lower content of β-pinene + sabinene, sesquiterpenes, and aliphatic aldehydes than Key lime oils. Oxypeucedanin was not detected in Key lime oil type A, while it is present in Key lime oil type B and Persian lime oil. This is probably due to the extraction technology used for Key lime oil type A, which allows the essential oil to come into contact with the juice. Under these conditions, the epoxy ring of oxypeucedanin is opened by hydrolysis to form oxypeucedanin hydrate. Keywords: Citrus aurantifolia Swingle; cold-pressed Key lime oil; type A; type B; Citrus latifolia Tanaka; cold-pressed Persian lime oil; volatile fraction; limonene; γ-terpinene; β-pinene + sabinene; coumarins; psoralens; oxypeucedanin
Article
BACKGROUND: Because of its extreme toxicity for microorganisms, the limonene content of citrus wastes (CWs) has been a major obstacle to the conversion of CWs to biofuels. The main objective of this study was to develop a new process for the utilization of CWs that can be economically feasible when the supply of CW is low.RESULTS: Steam explosion pre-treatment was applied to improve the anaerobic digestibility of CWs, resulting in a decrease of initial limonene concentration by 94.3%. A methane potential of 0.537 ± 0.001 m3 kg−1 VS (volatile solids) was obtained during the following batch digestion of treated CWs, corresponding to an increase of 426% compared with that of the untreated samples. Long-term effects of the treatment were further investigated by a semi-continuous co-digestion process. A methane production of 0.555 ± 0.0159 m3 CH4 kg−1 VS day−1 was achieved when treated CWs (corresponding to 30% of the VS load) were co-digested with municipal solid waste.CONCLUSION: The process developed can easily be applied to an existing biogas plant. The equipment cost for this process is estimated to be one million USD when utilizing 10 000 tons CWs year−1. 8.4 L limonene and 107.4 m3 methane can be produced per ton of fresh citrus wastes in this manner. Copyright © 2011 Society of Chemical Industry
Article
Production of ethanol, biogas, pectin and limonene from citrus wastes (CWs) by an integrated process was investigated. CWs were hydrolyzed by dilute-acid process in a pilot plant reactor equipped with an explosive drainage. Hydrolysis variables including temperature and residence time were optimized by applying a central composite rotatable experimental design (CCRD). The best sugar yield (0.41 g/g of the total dry CWs) was obtained by dilute-acid hydrolysis at 150 °C and 6 min residence time. At this condition, high solubilization of pectin present in the CWs was obtained, and 77.6% of total pectin content of CWs could be recovered by solvent recovery. Degree of esterification and ash content of produced pectin were 63.7% and 4.23%, respectively. In addition, the limonene of the CWs was effectively removed through flashing of the hydrolyzates into an expansion tank. The sugars present in the hydrolyzates were converted to ethanol using baker’s yeast, while an ethanol yield of 0.43 g/g of the fermentable sugars was obtained. Then, the stillage and the remaining solid materials of the hydrolyzed CWs were anaerobically digested to obtain biogas. In summary, one ton of CWs with 20% dry weight resulted in 39.64 l ethanol, 45 m3 methane, 8.9 l limonene, and 38.8 kg pectin.
Article
Traditional hydrodistillation (HD), cold pressing (CP) and innovative microwave ‘dry’ distillation or microwave-accelerated distillation (MAD) methods have been compared and evaluated for their effectiveness in the isolation of essential oil from fresh Citrus peels. The microwave method offers important advantages over traditional alternatives, viz. shorter extraction times (30 min vs. 3 h for hydrodistillation and 1 h for cold pressing); better yields (0.24% vs. 0.21% for HD and 0.05% for CP); environmental impact (energy cost is appreciably higher for performing HD and for mechanical motors (CP) than that required for rapid MAD extraction); cleaner features (as no residue generation and no water or solvent used); increases antimicrobial activities; and provides a more valuable essential oil (with high amounts of oxygenated compounds). It also offers the possibility for better reproduction of the natural aroma of the essential oil from Citrus fruit compared with CP, but more than the HD essential oil. Further, the microwave procedure yields essential oils that can be analysed or used directly without any clean-up, solvent exchange or centrifugation steps. Scanning electron microscopy provides more evidence of the cleanness of microwave extraction, in contrast to the huge perforations on the external surface of the Citrus fruit peel in the case of conventional hydrodistillation. Finally, a mechanism of microwave ‘dry’ distillation is proposed and discussed. Copyright © 2007 John Wiley & Sons, Ltd.