Effect of the extraction solvent polarity on the sesame seeds oil composition

Alternate solvent for soybean oil extraction based on extractability and membrane solvent recovery

Ethyl acetate, acetone, 2-propanol, 1-propanol, and ethanol were screened among the class 3 category solvents as an alternative to hexane based on operational and occupational safety and bio-renewability potential. All five solvents exhibited higher extractability (22.3 to 23.2%) than hexane (21.5%) with soybean flour. Additionally, there was no significant difference in the fatty acid and triacylglycerol (TAG) composition of the oils extracted using alternate solvents and hexane, indicating the oil quality was not affected. More importantly, ethyl acetate (2.1%) resulted in a marginally higher yield of TAG, while 2-propanol showed a nearly equal yield to hexane. Further, membrane desolventizing was attempted to mitigate the limitations of higher thermal energy requirements. One of the polydimethylsiloxane membranes exhibited good selectivity (TAG rejection 85.8%) and acceptable flux (59.3 L·m-2·h-1) with an ethyl acetate miscella system. Under plant-simulated recirculation conditions, a two-stage membrane process reduced the oil content in permeate to 2.5%. The study revealed that ethyl acetate could potentially replace hexane, considering its higher TAG extractability and suitability for the membrane-augmented solvent recycling process in the extraction plants.

The occurrence of aflatoxins and labelling compliance of locally produced za'atar mix products

Za'atar mix products are mainly composed of the dried and ground leaves and/or blossoms of wild and cultivated plant species (Origanum, Thymbra, Thymus, and Satureja) with the addition of condiments. The aim of this study was to evaluate the occurrence of aflatoxins, chemical composition (carbohydrates, fibre, fat, protein, moisture, ash, and acid contents), mineral content (Na, Ca, and K), and colour traits (L*a*b*) in relation to food label and food standards compliance. Measured and labelled fat content did not agree for approximately 91% of the samples. There was also no agreement between the measured and labelled fibre contents. The total content of aflatoxins in the tested samples ranged from 2 to 63.7 ng g-1. Eleven (69%) of the 16 analysed products had total aflatoxins higher than the maximum permitted limit of the European Commission. The KAS and LAZ products had significantly lighter colour (the highest L* values), while the ALAQ product had the darkest colour (lowest L* value). The range of sodium content in the tested products was 105.1-1425.3 mg/100 g. In conclusion, za'atar mix products that are available in local markets do not have accurate nutritional labelling information, and the occurrence of aflatoxins was very high. Further studies are needed to evaluate the reasons for these quality defects.

Lipidomics insight on differences in lipid profiles and phytosterol compositions of coconut oils extracted by classical and green solvents

Searching for green and ecofriendly solvents to replace classical solvents for industrial scale extraction of coconut oil is of great interest. To explore these possibilities, this study performed comprehensive comparative analyses of lipid profiles and phytosterol compositions in coconut oils obtained by extraction with n-hexane, absolute ethyl alcohol, deep eutectic solvent/n-hexane, dimethyl carbonate (DME) and cyclopentyl methyl ether (CPME) using a foodomics approach. Results indicated that CPME (64.23 g/100 g dry matter) and DME (65.64 g/100 g dry matter) showed comparable capacity for total lipid extraction of total lipids to classical solvents (63.5-65.66 g/100 g dry matter). Considering the phytosterol yield, CPME (644.26 mg/kg) exhibited higher selectivity than other solvents (535.64-622.13 mg/kg). No significant difference was observed in the fatty acid composition of coconut oil by the different solvents assayed. Additionally, total 468 lipid molecules were identified in the samples. For glycerolipid and sphingolipid, the five solvents showed comparable extraction capabilities. However, CPME exhibited higher extraction efficiency of polar lipids (glycerophospholipid and saccharolipid) than other solvents. Overall, these results may be a useful guide for the application of green solvents in industrial production of coconut oil.

Essential Components from Plant Source Oils: A Review on Extraction, Detection, Identification, and Quantification

Oils derived from plant sources, mainly fixed oils from seeds and essential oil from other parts of the plant, are gaining interest as they are the rich source of beneficial compounds that possess potential applications in different industries due to their preventive and therapeutic actions. The essential oils are used in food, medicine, cosmetics, and agriculture industries as they possess antimicrobial, anticarcinogenic, anti-inflammatory and immunomodulatory properties. Plant based oils contain polyphenols, phytochemicals, and bioactive compounds which show high antioxidant activity. The extractions of these oils are a crucial step in terms of the yield and quality attributes of plant oils. This review paper outlines the different modern extraction techniques used for the extraction of different seed oils, including microwave-assisted extraction (MAE), pressurized liquid extraction (PLE), cold-pressed extraction (CPE), ultrasound-assisted extraction (UAE), supercritical-fluid extraction (SFE), enzyme-assisted extraction (EAE), and pulsed electric field-assisted extraction (PEF). For the identification and quantification of essential and bioactive compounds present in seed oils, different modern techniques-such as high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared spectroscopy (FTIR), gas chromatography-infrared spectroscopy (GC-IR), atomic fluorescence spectroscopy (AFS), and electron microscopy (EM)-are highlighted in this review along with the beneficial effects of these essential components in different in vivo and in vitro studies and in different applications. The primary goal of this research article is to pique the attention of researchers towards the different sources, potential uses and applications of oils in different industries.

Value-added processing of seeds from tomato sauce industry and comparison of extraction solvents on the chemical properties

BACKGROUND

Tomato seed oil (TSO) was obtained using a combined method of pre-keeping in solvent and Soxhlet extraction. A considerable oil yield could not be obtained using samples without drying or grinding, with dried or non-dried seeds, which were not kept in solvent (<2%). For this purpose, oil yield, physicochemical properties, oxidation values, spectrophotometric indices and fatty acid composition of the samples extracted with acetone, ethyl acetate, chloroform and petroleum ether were determined.

RESULTS

Oils obtained by the extraction of petroleum ether (20.36 meq g O₂ kg^-1 ) and ethyl acetate (11.16 meq g O₂ kg^-1 ) were found to have very high peroxide values. Besides, a high-quality edible oil should have an anisidine value (p-AnV) of less than 10. Samples extracted with chloroform alone had a p-AnV of 8.86, while slightly higher values were found for other samples (P < 0.05). Chloroform (20.50) and acetone (23.06) both gave the best results and met the expected value, with total oxidation value below 30. Finally, the highest levels of primary fatty acids observed were linoleic acid (32.77-41.95%), palmitic acid (23.75-32.27%), oleic acid (16.17-24.52%), and stearic acid (7.76-12.82%).

CONCLUSION

This process is applicable to recycling tomato sauce waste and essential oil. The research proved that the seed-drying process and pre-keeping in solvent have an important effect on oil yield, quality and fatty acid composition. © 2023 Society of Chemical Industry.

Lesser mealworm (Alphitobius diaperinus L.) larvae oils extracted by pure and binary mixed organic solvents: Physicochemical and antioxidant properties, fatty acid composition, and lipid quality indices

Insect oil is one of the most sustainable lipid sources with remarkable health effects. Herein, the type of organic solvents (i.e., n-hexane, ethanol, and isopropanol) and their binary mixtures was evaluated based on the quantity (e.g., yield extraction) and quality (e.g., bioactive compounds, thermal stability, DPPH scavenging rate, fatty acid profile, and nutritional indices) of lesser mealworm oils. The oils extracted by ethanol/isopropanol and ethanol/n-hexane significantly showed the highest extraction yield and efficiency, lightness, accelerated thermal stability, phenolics, tocopherols, vitamin D, campesterol, β-sitosterol, phosphatidylinositol and phosphatic acid, linoleic acid, and hypocholesterolemic/hypercholesterolemic ratio, while these organic mixtures meaningfully extracted lipids with the lowest peroxide value, free fatty acid, and atherogenicity and thrombogenicity indices. These solvents compared to pure ones could dissolve membrane and internal lipids with the complete disintegration of external structures. The ethanol/isopropanol mixture would be a promising solvent for n-hexane substitution to extract this oil on an industrial scale.

Comparative study on quality characteristics of Bischofia polycarpa seed oil by different solvents: Lipid composition, phytochemicals, and antioxidant activity

Bischofia polycarpa seed oil is rich in nutrition and positively affects on human health. We analyzed and compared the chemical compositions, antioxidant activities, and quality characteristics of Bischofia polycarpa seed oils using different solvents and cold-pressing. Hx: Iso (n-hexane/isopropanol, 3:2 v/v) had the highest lipid yield (35.13 %), while Folch (chloroform/methanol, 2:1 v/v) had the highest linolenic acid (50.79 %), LnLnLn (43.42 %), and LnLnL (23.43 %). Tocopherols (2108.99 mg/kg) were extracted most efficiently with Folch, whereas phytosterols (3852.97 mg/kg) and squalene (55.21 mg/kg) were extracted most efficiently with petroleum ether. Although the lower phytosterol was obtained using isopropanol, the polyphenol content (271.34 mg GAE/kg) was significantly higher than other solvents, showing the best antioxidant ability. Additionally, polyphenols were observed to be the most significant factor predicting antioxidant activity from the correlation analysis. The above information can provide a useful reference for manufacturers to obtain satisfactory Bischofia polycarpa seed oil.

Optimization of Oil Extraction from Rice Bran with Mixed Solvent Using Response Surface Methodology

In order to improve the extraction ratio of rice bran oil, a single-factor experiment and response surface methodology with a central composite design were used to determine a new mixed solvent and the optimal extraction conditions of the mixed solvent. The effects of solid-liquid ratio, extraction time, extraction temperature, and oscillation speed on the extraction ratio were investigated. The regression equation was established, and the optimal extraction conditions were determined as follows: a solid-liquid ratio of 5.5:1, extraction temperature of 45 °C, extraction time of 12 min, and extraction ratio of rice bran oil of 85.8%. Compared with traditional solvent extraction, the peroxide value, acid value, iodine value, and fatty acid composition content of rice bran oil extracted using the new mixed solvent were close to those of n-hexane and significantly lower than those of solvent No. 6, while the content of oryzanol and total sterol increased to 2.7% and 5.1%. This study can be useful in exploring the possibility of new mixed solvents and provide theoretical guidance and data support for the production practice of new mixed solvents.

Effect of Different Solvents on the Extraction of Oil from Peony Seeds (Paeonia suffruticosa Andr.): Oil Yield, Fatty Acids Composition, Minor Components, and Antioxidant Capacity

Peony seed oil is full of nutrition and exert positive effects on human's health. The influences of seven solvents (isopropanol, acetone, Hx:Iso (n-hexane/isopropanol, 3:2 v/v), Chf:Me (chloroform/methanol, 1:1 v/v), ethyl acetate, n-hexane, and petroleum ether) on the oil yields, lipid composition, minor components and antioxidant capacity of peony seed oil were compared in this study. Results indicated that the highest oil yield (35.63%) was obtained using Hx:Iso, while Chf:Me showed the best extraction efficiency for linolenic acid (43.68%), trilinolenoyl-glycerol (15.00%), and dilinolenoyl-linoleoyl-glycerol (18.01%). For minor components, Chf:Me presented a significant advantage in the extraction of tocopherol (601.49 mg/kg), and the peony seed oil extracted with petroleum ether had the highest sterols (4089.82 mg/kg) and squalene contents (66.26 mg/kg). Although the use of isopropanol led to a lower sterol content, its extracts showed a significant higher polyphenol content (68.88 mg GAE/kg) than other solvents and exhibited the strongest antioxidant capacity. Additionally, correlation analysis revealed that polyphenols were the most important minor component for predicting the antioxidant capacity of peony seed oil. The above information is valuable for manufacturers to select suitable solvents to produce peony seed oil with the required levels of fatty acids and minor components for targeted end-use.

Alternative Methods of Bioactive Compounds and Oils Extraction from Berry Fruit By-Products—A Review

Berry fruit by-products are a source of polyphenol compounds and highly nutritious oils and can be reused to fulfill the requirements of the circular economy model. One of the methods of obtaining polyphenol-rich extracts or oils is extraction. Applying conventional solvent extraction techniques may be insufficient to reach high polyphenol or lipid fraction yields and selectivity of specific compounds. Alternative extraction methods, mainly ultrasound-assisted extraction, pulsed electric field-assisted extraction, microwave-assisted extraction and supercritical fluid extraction, are ways to improve the efficiency of the isolation of bioactive compounds or oils from berry fruit by-products. Additionally, non-conventional techniques are considered as green extraction methods, as they consume less energy, solvent volume and time. The aim of this review is to summarize the studies on alternative extraction methods and their relationship to the composition of extracts or oils obtained from berry waste products.

Impact of Hydro-Alcoholic Solvents on the Oil and Phenolics Extraction from Walnut (Juglans regia L.) Press-Cake and the Self-Emulsification of Extracts

The objective was to evaluate the performance of four hydro-alcoholic solvents to simultaneously extract oil and more polar molecules as phenolics, among others, to produce complex extracts that eventually could self-emulsify after solvent removal. Walnut press-cake was selected as the sourcing material. Extractions were performed as a semi-continuous operation up to a solvent-to-solid ratio of 28, with a fractional collection of the effluent. Among the solvents, labelled by their alcohol content EtOH 58, EtOH 86, iPro 60 and iPro 90 for ethanol (EtOH) and isopropanol (iPro), iPro 90 allowed to reach an oil extraction efficiency of 97% while the recovery for the other solvents was in the range of 30–40%. For both alcohols, the increase of the solvent hydration negatively influenced the oil extraction but positively increased the recovery of phenolics that reached 17.6 mg GAE/g_cake when EtOH 58 was used. Several fractions contained enough surface-active material and oil to self-assemble as emulsions. IPro 90 and EtOH 86 showed better performances in the sense that most extracts were able to emulsify, though extraction kinetics pointed out differences. The most hydrated solvents behaved equally, with extraction yields in the same range and a similar but limited emulsifying capacity of only few fractions.

A machine learning approach for predicting the empirical polarity of organic solvents

A neural network architecture was found to efficiently predict the empirical polarity parameter ET(30) using simple to compute and interpretable six quantum mechanical, topological and categorical descriptors.

Quantitative Polyunsaturated Fatty Acid Analysis of Chia Seed Oil by High-Performance Liquid Chromatography

Alpha-linolenic acid (ALA) and linoleic acid (LA), abundant in chia seed oil, are useful polyunsaturated fatty acids (PUFA) with numerous health benefits. The objectives of the present study were to explore the optimum extraction condition of chia seed oil and the possibilities of direct analysis of ALA and LA in chia seed oil by reversed-phase high-performance liquid chromatography with ultraviolet detection (RP-HPLC-UV). The optimized chia seed oil extraction condition was set by the usage of Soxhlet extrator with hexane as a solvent, with the solvent to solid ratio of 8 and the extraction time of 8 h. Prior to HPLC-UV analysis, the oil was saponified in order to get the free fatty acids for detection. The results showed that the proposed HPLC-UV method allowed the quantification of ALA and LA in chia seed oil. The method was simple, rapid (within 18 min) and sensitive (limit of detection 0.006 mg/mL for ALA and 0.02 mg/mL for LA) and precise (RSD ≤ 2%). Thus, the proposed experimental designs were shown to offer considerable advantages over traditional derivatization approaches in the ALA and LA analyses.

Chemical and Fatty Acid Compositions of Crude and Purified Extracts Obtained from Datura innoxia Seeds Extracted with Different Solvents

Oils play a key role as raw materials in a variety of industries. The aim of this study was to evaluate the potential of Datura innoxia seed oil cultivated in Saudi Arabia for industrial purpose and to study the effects of hexane, chloroform, and isopropanol as extraction solvents on the compositions of the extracts. The results showed that the hexane and chloroform extracts were mainly neutral oils which were rich in linoleic (≈46%) and oleic (≈31%) acids. However, the isopropanol extract contained large amount of neutral oil and organic acids. Neutral oil contained mainly palmitic acid (40.2%) and some important and valuable epoxy (15.4%) and cyclopropane (13.2%) fatty acids. Analysis of the sterol and tocopherol levels of the crude and purified oil extracted revealed that they were significantly affected by the extraction solvent used.

Plant-Based Phenolic Molecules as Natural Preservatives in Comminuted Meats: A Review

Comminuted meat products are highly susceptible to safety and quality degradation partly because of their large interfacial area in the emulsion. The food industry extensively uses synthetic chemical preservatives to delay that degradation which is caused by microbial growth, enzyme activities and oxidation reactions. However, due to the potential health damage (e.g., cardiovascular diseases, neurodegenerative diseases, cancers among others) synthetic preservatives in meat may cause, consumers are becoming skeptical to buy meat products containing such additives. In the meat industry, the interest of finding natural food preservatives is intensifying. Polyphenolic-rich plants used as natural food preservatives offer the best alternative for a partial or a complete replacement of their synthetic counterparts. They can be extracted from natural sources such as olives, fruits, grapes, vegetables, spices, herbs, and algae, and among others. The common feature of these phenolic compounds is that they have one or more aromatic rings with one or more -OH group which are essential for their antimicrobial and antioxidant properties. This review article is intended to provide an overview of the plant-based phenolic molecules used as natural food preservative, their antimicrobial and antioxidant mechanism of action, and their potential application in comminuted meat.

The bioactive compounds and cellular antioxidant activity of Herbaceous peony (Paeonia lactiflora Pall) seed oil from China

Herbaceous peony (HP) seed oil has been consumed in some regions of China, yet little information is available on its bioactive composition and antioxidant activity. This study aimed to evaluate the fatty acid compositions, micronutrients contents, and cellular antioxidant activity (CAA) of HP seed oil from five varieties. Results indicated that this oil had high percentages of monounsaturated (32.15 to 45.92%) and polyunsaturated fatty acids (58.65 to 61.95%), and the α-linolenic acid C18:3 was the highest in Fushao seed oil. Additionally, the high concentrations of tocopherol and phytosterol were found in all seed oils, and 10 individual polyphenols have been evaluated. Fushao seed oil had the highest polyphenols levels and showed higher CAA values. Both hierarchical cluster analysis and principal component analysis have been used to distinguish HP seed oil from different varieties. This information is valuable for the nutritional value and industrial interest of HP seed oil in China. PRACTICAL APPLICATION: This research showed that Herbaceous peony seed oil had higher levels of minor components and polyunsaturated fatty acids, especially, α-linolenic acid, and our results could also provide the theoretical foundation for the health benefits of Herbaceous peony seed oil as the vegetable oils. However, the variety of Herbaceous should be considered when extracting oil from Herbaceous peony seeds in the industry.

Effect of Microwave Pretreatment of Seeds on the Quality and Antioxidant Capacity of Pomegranate Seed Oil

Microwave pretreatment of oilseeds is a novel technique used to enhance oil nutraceutical properties. In this study, the effect of microwave pretreatment of seeds was investigated on pomegranate seed oil quality attributes including oil yield, yellowness index, refractive index, peroxide value, ρ-anisidine value, total oxidation value, conjugated dienes, total phenolic content, total carotenoids content, phytosterol composition, fatty acid composition, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, and ferric reducing antioxidant power (FRAP). The seeds of three different pomegranate cultivars ('Acco', 'Herskawitz', and 'Wonderful') were microwave heated at 261 W for 102 s. Pomegranate seeds microwave pretreatment enhanced oil yield, yellowness index, total carotenoids content, total phenolic content, FRAP and DPPH radical scavenging capacity, despite an increase in conjugated dienes, and peroxide value. Palmitic acid, oleic acid, linoleic acid, saturated, and monosaturated fatty acids were increased after pomegranate seeds microwave pretreatment, whilst the levels of punicic acid and β-sitosterol were reduced. Nevertheless, the refractive index, the ratio of unsaturated to saturated fatty acid of the extracted oil were not significantly (p > 0.05) affected by pomegranate seeds microwave pretreatment. Principal component analysis and agglomerative hierarchical clustering established that 'Acco' and 'Wonderful' oil extracts from microwave pretreated PS exhibited better oil yield, whilst 'Herskawitz' oil extracts showed higher total carotenoids content, total phenolic content, and antioxidant capacity.

Synergistic effects of ultrasound and extraction solvent on the bioactive compound in kenaf seed oil

Kenaf seed oil was extracted with 3 different solvents, i.e. hexane, ethanol and aqueous enzymatic medium with or without ultrasonic assistance. The synergistic effects of ultrasound and extraction solvent on the content of bioactive compound in kenaf seed oil was investigated. Results show that ultrasound-assisted extraction with hexane obtained the highest yield (84.71%), while yield with aqueous enzymatic medium was the lowest (51.12%). Two endothermic peaks exhibited on the melting curve of kenaf seed oil at the temperature range - 37 to - 25 °C and - 12 to - 2 °C, respectively. Linoleic, oleic and palmitic acid are the major fatty acids, accounting for above 96% of the total fatty acids. The content of vitamin E, phosphatide, total phenols and sterol are 92.38-105.01 mg/100 g oil, 0.38-22.28 g/kg, 0.51-71.02 mg GAE/100 g and 161.79-533.12 mg/100 g, respectively. The solvent employed has significant effect (p < 0.05) on the thermal property, fatty acid composition and bioactive constituents of the extracted kenaf seed oil. The oil extracted with ethanol contained more nervonic acid and bioactive components such as β-carotene, phosphatide, total phenols and sterols. The introduction of ultrasound reduced the extraction time remarkably. The results demonstrate that extraction with ethanol combined with ultrasound is an effective method to extract kenaf seed oil, as more reasonable fatty acid composition and higher content of bioactive components can be achieved.

Effect of Blanching Pomegranate Seeds on Physicochemical Attributes, Bioactive Compounds and Antioxidant Activity of Extracted Oil

This study investigated the effect of blanching pomegranate seeds (PS) on oil yield, refractive index (RI), yellowness index (YI), conjugated dienes (K232), conjugated trienes (K270), total carotenoid content (TCC), total phenolic compounds (TPC) and DPPH radical scavenging of the extracted oil. Furthermore, phytosterol and fatty acid compositions of the oil extracted under optimum blanching conditions were compared with those from the oil extracted from unblanched PS. Three different blanching temperature levels (80, 90, and 100 °C) were studied at a constant blanching time of 3 min. The blanching time was then increased to 5 min at the established optimum blanching temperature (90 °C). Blanching PS increased oil yield, K232, K270, stigmasterol, punicic acid, TPC and DPPH radical scavenging, whereas YI, β-sitosterol, palmitic acid and linoleic acid were decreased. The RI, TCC, brassicasterol, stearic acid, oleic acid and arachidic acid of the extracted oil were not significantly (p > 0.05) affected by blanching. Blanching PS at 90 °C for 3 to 5 min was associated with oil yield, TPC and DPPH. Blanching PS at 90 °C for 3 to 5 min will not only increase oil yield but could also improve functional properties such as antioxidant activity, which are desirable in the cosmetic, pharmaceutical, nutraceutical and food industries.

Physico-Chemical Properties and Oxidative Stability of Fixed Oil from Plum Seeds (Prunus domestica Linn.)

Storage of a great amount of plum kernel waste becomes a challenge for food industry. In this work, the plum seed was used as a source of fixed oil that can be an ingredient of commercial products. Soxhlet extraction was carried out using the different solvents, such as n-hexane, n-heptane, ethyl acetate, acetone, or chloroform:methanol mixture (2:1 v/v). The highest yield of oil (about 30%) was obtained using n-heptane and n-hexane, while the lowest yield was obtained using ethyl acetate. The analysis of physico-chemical parameters indicated that all samples of plum seed oil have an exceptional quality. Schaal oven test indicated that the fixed oil of plum seed exhibited satisfactory oxidative stability at moderate storage temperatures (up to 65 °C). The composition of phenolic compounds in the oil samples was determined using HPLC method. The most abundant compound of seven identified and quantified phenolic compounds was vanillic acid. The highest content of β-carotene (1.67 mg 100 g⁻¹ fixed oil) spectrophotometrically determined was in the oil extracted with n-hexane. The lowest content of β-carotene (1.26 mg 100 g⁻¹ fixed oil) was determined in the oil extracted with a mixture of chloroform:methanol (2:1 v/v). This oil had the highest antioxidant activity (IC₅₀ value of 4.35 mg mL⁻¹) compared to other oil samples. The antioxidant activity was probably caused by the presence of phenolic compounds. The investigated physico-chemical properties demonstrated that the plum seed oil has a potential for application in the food, cosmetics, and pharmaceutical industry.

Extraction of carotenoid-rich palm pressed fiber oil using mixtures of hydrocarbons and short chain alcohols

Solvent extraction is the most efficient method for recovering residual oil from palm pressed fiber (PPFO), which may contain up to eight times the carotenoid content of that found in crude palm oil. The objective of the present study is the use of binary mixtures of hydrocarbons (HC), hexane (Hex), cyclohexane (CHex) or heptane (Hep), and alcohols (ALC), ethanol (Eth) or isopropanol (IPA), in order to promote the highest recovery of a carotenoid-rich PPFO, in which the compositions of the mixtures are defined based on the calculation of solute-solvent distance (Ra) considering β-carotene as the solute. The extraction experiments were conducted in batch, at 60 ± 2 °C, or in a fixed-bed packed column, at 55 ± 3 °C. Hex and Hep:IPA provided 80% of batch PPFO extraction yield, while in column, the highest yields were obtained with Eth and Hex:IPA (66%). The total carotenoid content obtained was the same independent of the solvent and extraction configuration (from 1790 ± 230 up to 2539 ± 78 mg β-carotene/kg PPFO). In terms of the carotenoid profile, β-carotene was mostly extracted by Hex, Hex:Eth stood out in the extraction of α-carotene, and Eth extracted the highest content of lycopene. It is possible to infer that mixtures of HC and ALC with compositions defined based on Hansen Solubility Parameters (HSPs) demonstrated good ability to extract carotenoid-rich PPFO, maintaining their relatively stable fatty acids composition and free acidity, showing that partial substitution of HC by ALC is technically possible.

The Effect of Different Solvent Types and Extraction Methods on Oil Yields and Fatty Acid Composition of Safflower Seed

The aim of this study was to determine the effect of different extraction solvents (petroleum benzene, hexane, diethyl ether and acetone) and extraction methods (hot and cold) on oil yield of safflower seeds and its fatty acid compositions. Oil contents of safflower seeds extracted by hot extraction system were changed between 37.40% (acetone) and 39.53% (petroleum benzene), while that of cold extraction was varied between 39.96% (petroleum benzene) and 39.40% (diethyl ether). Regarding the extraction solvents, the highest oil yield (39.53%) was obtained with petroleum benzene, while the minimum value (37.40%) was found with acetone under hot extraction condition. The main fatty acids observed in all extracted oil samples were linoleic, oleic and palmitic acids. Oleic acid contents of safflower oils extracted by hot extraction system was ranged between 41.20% (acetone) and 42.54% (hexane), its content in oils obtained by cold extraction method was varied between 40.58% (acetone) and 42.10% (hexane and diethyl ether). Linoleic content of safflower oil extracted by hot extraction system was found between 48.23% (acetone) and 49.62% (hexane), while that oil extracted by cold method range from 48.07 (hexane) to 49.09% (acetone). The fatty acid composition of safflower seeds oil showed significant (p < 0.05) differences depending on solvent type and extraction method. The results of this study provide relevant information that can be used to improve organic solvent extraction processes of vegetable oil.

Optimization of lipid extraction from the oleaginous yeasts Rhodotorula glutinis and Lipomyces kononenkoae

The constant growing demand for vegetable oil for biodiesel and food is raising many environmental concerns about the sustainability of its production based on crops. Oleaginous yeasts show great potential to end with those concerns due to their high lipid productivity in small areas. To evaluate their productivity in lipids, an efficient and reproducible extraction process should be used. As no standard extraction process is available for the extraction of yeast lipids, an optimized extraction process is presented. In this work, the lipids extraction process for the yeasts Rhodotorula glutinis and Lipomyces kononenkoae is optimized using bead beating for cell rupture and introducing adaptations of the two most used extraction methods (Bligh and Dyer and Folch). For Rhodotorula g. the optimum extraction conditions are obtained by the Bligh and Dyer method applying 4.8 cycles of 47 s with 0.7 g of glass beads. For Lipomyces k. the optimum extraction conditions make use of the Folch method applying seven cycles of 42 s with 0.54 g of glass beads. These results reinforce the idea that, for each yeast, different extraction processes may be needed to correctly determine the lipid yield. The extraction procedure was further evaluated with less harmful solvents. Toluene was tested as a possible substitute of chloroform, and ethanol as a possible substitute of methanol. With the optimized extraction process, better results for Lipomyces k. were obtained using toluene and ethanol, while for Rhodotorula g. toluene proved to be a valid substitute of chloroform but ethanol is far less effective than methanol.

Identification and evaluation of anti-inflammatory properties of aqueous components extracted from sesame (Sesamum indicum) oil

We previously reported that sesame oil (SO) has anti-inflammatory, anti-atherosclerotic and lipid lowering properties in vivo. Our recent studies have shown that, an aqueous extract of sesame oil (SOAE) has also anti-inflammatory and anti-atherosclerotic properties but with no lipid lowering effects. The extent of reduction in atherosclerosis led us to identify components of SOAE and evaluate their anti-inflammatory properties in vitro. Liquid chromatography mass spectrometric method was used to detect and identify components of SOAE. Methoxyphenol derivatives, short and long chain carboxylic acids, dicarboxylic acids, hydroxy and oxo- carboxylic acids were detected. To our surprise, sesamol and its derivatives (lignans), were not present in the SOAE. Among the identified, a combination of methoxy phenol compounds were selected and tested their ability to reduce LPS induced inflammatory gene expression. Monocyte derived macrophages/RAW 264.7 macrophages were pre-treated with these compounds for 2 h, followed by LPS stimulation for 24 h and pro-inflammatory gene expressions were analyzed. These methoxyphenol derivatives showed potent anti-inflammatory properties. In conclusion, the anti-inflammatory molecules associated with SO may contribute the anti-inflammatory and anti-atherosclerotic properties. Also, our results shed light for the development of SOAE based non-pharmacological therapeutics, nutritional supplements and health products for various inflammatory diseases in the future.

Effect of the type and level of hydration of alcoholic solvents on the simultaneous extraction of oil and chlorogenic acids from sunflower seed press cake

BACKGROUND

The present study aimed to evaluate the replacement of hexane by alcoholic solvents in oil extraction from sunflower seed press cake. The use of ethanol and isopropanol has important advantages, including low toxicity and good operational safety. Thus, in the present study, solid-liquid extractions were performed in a single stage from 60 to 90 °C and in consecutive extractions in three stages at 90 °C.

RESULTS

Solvent hydration negatively affected the extraction of oil but favored the extraction of chlorogenic acids (CAs), especially when ethanol was used. Regarding oxidative stability, the oils extracted using ethanol presented long induction times, which could be related to the high levels of not only CAs and tocopherols, but also phospholipids.

CONCLUSION

Alcoholic solvents can be used for extraction to produce sunflower seed oil containing minor compounds that give it greater oxidative stability. In addition, the results obtained using hydrous ethanol showed that this solvent can yield defatted sunflower seed meal with a low content of CAs, enabling future use of the protein fraction. © 2017 Society of Chemical Industry.

Efficient salt-aided aqueous extraction of bitter almond oil

BACKGROUND

Salt-aided aqueous extraction (SAAE) is an inexpensive and environmentally friendly method of oil extraction that is influenced by many factors. In the present study, we investigated the effect of SAAE on bitter almond oil yield.

RESULTS

This study used sodium bicarbonate solution as extraction solvent and the optimal extraction parameters predicted by Box-Behnken design (i.e., concentration of sodium bicarbonate, 0.4 mol L^-1 ; solvent-to-sample ratio, 5:1; extraction temperature, 84 °C; extraction time, 60 min), for oil recovery of 90.9%. The physiochemical characteristics of the extracted oil suggest that the quality was similar to that of the aqueous enzymatic extracted oil. Moreover, the content of hydrocyanic acid (HCN) in bitter almond oil was found to be less than 5 mg kg^-1 , which was lower compared to that obtained by other reported methods. Results of microanalysis indicated that SAAE led to significant improvement in oil yield by allowing the release of oil and decreasing the emulsion fraction. Therefore, extraction of bitter almond oil by SAAE is feasible.

CONCLUSION

These results demonstrate that extraction of bitter almond oil by SAAE based on the salt effect is feasible on a laboratory scale. © 2017 Society of Chemical Industry.