Extraction of phytosterols and tocopherols from rapeseed oil waste by supercritical CO2 plus co-solvent: A comparison with conventional solvent extraction

Optimizing ethanol-modified supercritical CO₂ extraction for enhanced bioactive compound recovery in hemp seed oil

This work aimed to extract hemp seed oil using modified supercritical CO2 with ethanol, while optimizing the overall process through response surface methodology. The effects of extraction temperature (30-60 °C), pressure (10-20 MPa), and time (120-300 min) on oil yield, total phenols (TPC), total tocopherols, oxidative stability index (OSI), total chlorophylls, total carotenoids, quality indices, and color were assessed. For a maximum yield of 28.83 g/100 g of fresh seeds, the oil was extracted at 50 °C and 20 MPa for 244 min. In addition, CO2 modified with different proportions of ethanol (2.5-20%) under the optimized SFE conditions was also tested for enhancing phenolic compound extractability in hemp seed oil. The best proportion was 10% ethanol, which significantly increased the oil yield to 30.13%, TPC to 294.15 GAE mg/kg, total tocopherols to 484.38 mg/kg, and OSI to 28.01 h, without affecting the quality parameters and the fatty acid profile. Furthermore, the phenolic compounds in the extracted oils were analyzed via HPLC-DAD/ESI-MS2. These findings indicated that CO2 modified with ethanol enhanced the extraction of phenolic compounds, 26 of which were identified. Among these, the most abundant compounds were N-trans-caffeoyltyramine, and cannabisins A and B, with concentrations of 50.32, 13.72, and 16.11 mg/kg oil, respectively. The oil obtained by SFE with SC-CO2 + ethanol could be valorized by evaluating its biological activities and its anti-aging, dermato-protective and antimicrobial properties for use in the cosmetics, pharmaceutical and food applications.

A comparative study of extraction methods for recovery of bioactive components from brown algae Sargassum serratifolium

Species of Sargassum genus are known to be rich sources of bioactive compounds. However, there is a lack of studies comparing extraction methods for these bioactive components. This study aimed to compare the total phenolic contents, total antioxidant capacity, tyrosinase inhibitory effect, sargahydroquinoic acid (SHQA) and sargachromenol (SCM), two algal meroterpenoids, of Sargassum serratifolium extracts acquired by different extraction methods. The methods employed in this study included conventional solid-liquid extraction using methanol (SME), supercritical fluid extraction using CO2 with ethanol as a co-solvent (SC-CO2 + ethanol), and pressurized liquid extraction (PLE) at two temperatures (25 and 100 °C). PLE at 100 °C (PLE100) exhibited the highest total yield, total phenolic content, total antioxidant capacity and tyrosinase inhibitory activity. Notably, SME resulted in the highest recovery of both SHQA and SCM. Compared to SME, PLE100 exhibited a two-fold increase in antioxidant capacity but a minimal increase in phenolic content.

Supercritical CO2 Extraction vs. Hexane Extraction and Cold Pressing: Comparative Analysis of Seed Oils from Six Plant Species

Supercritical fluid extraction using carbon dioxide (SFE-CO2) brings a convincing advance in the production of plant oils used in cosmetics, in fortified foods and dietary supplements, and in pharmaceuticals and medicine. The SFE-CO2-extracted, hexane-extracted, and cold-pressed plant oils of pumpkin (Cucurbita pepo L.), flax (Linum usitatissimum L.), linden (Tilia sp.), poppy (Papaver somniferum L.), apricot (Prunus armeniaca L.), and marigold (Calendula officinalis L.) seeds were investigated in terms of oil yield, fatty acid composition, unsaponifiable matter yield and composition, and the antioxidant activity of unsaponifiable matter. SFE-CO2 proved to be the preferred extraction method for four out of six plant materials, especially for seeds with lower oil content. However, for seeds with higher oil content, such as apricots, cold pressing is a viable alternative. A comparison of fatty acid composition did not reveal significant differences between extraction techniques. SFE-CO2 extraction improved the total phytosterol content of oils, especially pumpkin seed oil. A high variability in the antioxidant potential of the unsaponifiable matter studied was determined, with pumpkin seed oil showing the highest antioxidant activity. A correlation analysis was performed between unsaponifiable composition and antioxidant activity, and showed statistically significant correlations with squalene, cycloartenol, and an unidentified compound. This is the first comparison of the phytosterol compositions of linseed, apricot, linden, and marigold. Through continued optimization, SFE-CO2 has the potential to revolutionize the production of plant oils and provide a sustainable and efficient alternative.

Anti-inflammatory and antioxidant activity of functional lipids extracted through sustainable technologies from Mexican Opuntia ficus-indica seeds

Opuntia ficus-indica (OFI) seeds are a rich source of functional lipids, yet research on Mexican cultivars remains limited. This study evaluated the antioxidant and anti-inflammatory properties of lipids extracted through subcritical fluid and supercritical fluid extraction with carbon dioxide (SCE-CO₂ and SFE-CO₂) from Mexican OFI Villanueva and Rojo Vigor seeds with and without enzymatic pretreatment. SCE OFI Villanueva oil showed higher extraction efficiency of linoleic (45.86 mg/g), and oleic (9.86 mg/g) acids purified more than 5.47 and 1.18 times, respectively. Additionally, SCE oils exhibited the highest antioxidant potential (68 %) and anti-inflammatory activity (45 %) at the evaluated doses. In conclusion, SCE-CO₂ enhanced the extraction efficiency of unsaturated fatty acids, improving their potential biological effects, while enzymatic pretreatment did not positively impact on results, suggesting reduced extraction efficiency and bioactivity. These findings suggest that OFI seeds can serve as a valuable source of functional ingredients for the development of value-added food products.

High Pressure Extraction as a Green Alternative to the Conventional Sunflower Oil (Helianthus annuus) Production Process - Extraction with Pressurized Ethanol in an Intermittent Process and with Supercritical Fluid

This research explores green-technology alternatives to extract vegetable oils as alternatives to hexane, a non-renewable solvent, focussing on sunflower oil. It compares pressurized liquid extraction (PLE) with ethanol and supercritical fluid extraction (SFE) with CO2. Both processes aim to maximize oil yield, tocopherol content (α, β, γ, and δ), fatty acid profile (FA), and triacylglycerol (TAG) composition. Results show that SFE at 32 MPa achieves an 87.58% oil recovery, while PLE at 84 °C achieves 93.93%. PLE with ethanol extracts polar minority compounds along with the oil due to its higher temperature, favoring extraction. The total tocopherol content is 91.17 mg/100 g of oil in optimized SFE conditions, with α-tocopherol extraction influenced by temperature, γ and δ-tocopherol by pressure. PLE yields 83.16 mg/100 g of oil in tocopherols influenced less by process variables. The fatty acid (FA) profile do not vary in the oils obtained from different processes or based on the variables within each process, with linoleic and oleic acids being the most abundant. Similarly, triacylglycerols (TAGs) C54:5 and C54:6 are predominant. The optimization of SFE and PLE processes indicates a strong potential for using green solvents in the extraction of tocopherol-rich sunflower oil.

Review of available "extraction + purification" methods of natural ceramides and their feasibility for sewage sludge analysis

Natural ceramide, a biologically active compound present in plants, has been used widely in food, cosmetics, and pharmaceutical industries. Abundant ceramide has been detected in sewage sludge, which has inspired the idea to recycle ceramide from it. Therefore, the methods of extracting, purifying, and detecting ceramides from plants were reviewed, with the aim to establish methods to get condensed ceramide from sludge. Ceramide extraction methods include traditional methods (maceration, reflux, and Soxhlet extraction) and green technologies (ultrasound-assisted, microwave-assisted, and supercritical fluid extraction). In the past two decades, more than 70% of the articles have used traditional methods. However, green extraction methods are gradually improved and showed high extraction efficiency with lower solvent consumed. The preferred technique for ceramide purification is chromatography. Common solvent systems include chloroform-methanol, n-hexane-ethyl acetate, petroleum ether-ethyl acetate, and petroleum ether-acetone. For structural determination of ceramide, infrared spectroscopy, nuclear magnetic resonance spectroscopy, and mass spectrometry are used in combination. Among quantitative analysis methods for ceramide, liquid chromatography-mass spectrometry was the most accurate. This review concludes that with our prilemenary experiment results it is feasible to apply the plant "extraction + purification" process of ceramide to sludge, but more optimization need to be performed to get better results.

Pachira aquatica (Malvaceae): An unconventional food plant with food, technological, and nutritional potential to be explored

Pachira aquatica (Malvaceae) is an unconventional food plant (UFP) native to Mexico and found all over Brazil, where it is commonly known as monguba. It has an arboreal shape, exotic flowers, and a fruit similar to cocoa with several seeds. Although its main application is in urban ornamentation and folk medicine, monguba's fruit has a great potential for use in the food, pharmacology, cosmetic, and bioenergy industry, mainly due to its oil's characteristics. This review aims to compile the nutritional composition, bioactive and antioxidant activities, and technological and nutritional potential of monguba's seed, leaf, and fruit pericarp. It reviews studies of different databases between January 2018 and October 2021. Monguba seeds are rich in lipids, proteins, and minerals; the bark is rich in fiber; and all parts of the fruit have bioactive compounds. Discussing the use of UFP is a way of finding new alternative food sources, usually discarded, offering products with high nutritional value allied to technological and consumption potential, such as the monguba fruit.

Major Phytochemicals: Recent Advances in Health Benefits and Extraction Method

Recent scientific studies have established a relationship between the consumption of phytochemicals such as carotenoids, polyphenols, isoprenoids, phytosterols, saponins, dietary fibers, polysaccharides, etc., with health benefits such as prevention of diabetes, obesity, cancer, cardiovascular diseases, etc. This has led to the popularization of phytochemicals. Nowadays, foods containing phytochemicals as a constituent (functional foods) and the concentrated form of phytochemicals (nutraceuticals) are used as a preventive measure or cure for many diseases. The health benefits of these phytochemicals depend on their purity and structural stability. The yield, purity, and structural stability of extracted phytochemicals depend on the matrix in which the phytochemical is present, the method of extraction, the solvent used, the temperature, and the time of extraction.

Polyphenolic compounds from rapeseeds (Brassica napus L.): The major types, biofunctional roles, bioavailability, and the influences of rapeseed oil processing technologies on the content

The rapeseed (Brassica napus L.) are the important oil bearing material worldwide, which contain wide variety of bioactive components with polyphenolic compounds considered the most typical. The rapeseed polyphenols encompass different structural variants, and have been considered to have many bioactive functions, which are beneficial for the human health. Whereas, the rapeseed oil processing technologies affect their content and the biofunctional activities. The present review of the literature highlighted the major types of the rapeseed polyphenols, and summarized their biofunctional roles. The influences of rapeseed oil processing technologies on these polyphenols were also elucidated. Furthermore, the directions of the future studies for producing nutritional rapeseed oils preserved higher level of polyphenols were prospected. The rapeseed polyphenols are divided into the phenolic acids and polyphenolic tannins, both of which contained different subtypes. They are reported to have multiple biofunctional roles, thus showing outstanding health improvement effects. The rapeseed oil processing technologies have significant effects on both of the polyphenol content and activity. Some novel processing technologies, such as aqueous enzymatic extraction (AEE), subcritical or supercritical extraction showed advantages for producing rapeseed oil with higher level of polyphenols. The oil refining process involved heat or strong acid and alkali conditions affected their stability and activity, leading to the loss of polyphenols of the final products. Future efforts are encouraged to provide more clinic evidence for the practical applications of the rapeseed polyphenols, as well as optimizing the processing technologies for the green manufacturing of rapeseed oils.

Extraction, Isolation of Bioactive Compounds and Therapeutic Potential of Rapeseed (Brassica napus L.)

Rapeseed (Brassica napus L.) is a herbaceous annual plant of the Cruciferous family, the Cabbage genus. This oilseed crop is widely used in many areas of industry and agriculture. High-quality oil obtained from rapeseed can be found in many industrial food products. To date, extracts with a high content of biologically active substances are obtained from rapeseed using modern extraction methods. Brassica napus L. seeds contain polyunsaturated and monounsaturated fatty acids, carotenoids, phytosterols, flavonoids, vitamins, glucosinolates and microelements. The data in this review show that rapeseed biocompounds have therapeutic effects in the treatment of various types of diseases. Some studies indicate that rapeseed can be used as an anti-inflammatory, antioxidant, antiviral, hypoglycemic and anticancer agent. In the pharmaceutical industry, using rapeseed as an active ingredient may help to develop new forms drugs with wide range of therapeutic effects. This review focuses on aspects of the extraction of biocompounds from rapeseed and the study of its pharmacological properties.

Ganodiesel: A New Biodiesel Feedstock from Biomass of the Mushroom Ganoderma lucidum

There is a pressing demand for new sustainable eco-friendly approaches to producing green energy worldwide. This study represents the novel production of biodiesel feedstock from the medicinal mushroom Ganoderma lucidum QRS 5120 using state-of-the-art biotechnology tools. Response surface methodology (RSM) was used to enhance G. lucidum production in a repeated-batch fermentation strategy. By referring to the broth replacement ratio (BRR) and broth replacement time point (BRTP), RSM that was formulated using a central composite design (CCD) resulted in a significant model for all tested variables, which are exopolysaccharide (EPS), endopolysaccharide (ENS) and biomass, with BRR (%) of 60, 75 and 90, and BRTP (days) of 11, 13 and 15. The model was validated using the optimised conditions, and the results showed 4.21 g/L of EPS (BRR 77.46% and BRTP 12 days), 2.44 g/L of ENS (BRR 60% and BRTP 12.85 days), and 34.32 g/L of biomass (BRR 89.52% and BRTP 10.96 days) were produced. Biomass produced from the G. lucidum was subsequently used as feedstock for biodiesel production. Approximately 20.36% of lipid was successfully extracted from the dried G. lucidum biomass via a solvent extraction and subsequently converted to Ganodiesel through a transesterification process. The Ganodiesel produced fulfilled most of the international standards, i.e., US (ASTM D6751-08) and EU (EN 14214). Overall, this study demonstrates the optimised G. lucidum production and its lipid production as a new biodiesel feedstock.

Nutraceutical and Pharmaceutical Behavior of Bioactive Compounds of Miracle Oilseeds: An Overview

India plays an important role in the production of oilseeds, which are mainly cultivated for future extraction of their oil. In addition to the energic and nutritional contribution of these seeds, oilseeds are rich sources of bioactive compounds (e.g., phenolic compounds, proteins, minerals). A regular and moderate dietary supplementation of oilseeds promotes health, prevents the appearance of certain diseases (e.g., cardiovascular diseases (CVDs), cancers) and delays the aging process. Due to their relevant content in nutraceutical molecules, oilseeds and some of their associated processing wastes have raised interest in food and pharmaceutical industries searching for innovative products whose application provides health benefits to consumers. Furthermore, a circular economy approach could be considered regarding the re-use of oilseeds’ processing waste. The present article highlights the different oilseed types, the oilseeds-derived bioactive compounds as well as the health benefits associated with their consumption. In addition, the different types of extractive techniques that can be used to obtain vegetable oils rich from oilseeds, such as microwave-assisted extraction (MAE), ultrasonic-assisted extraction (UAE) and supercritical fluid extraction (SFE), are reported. We conclude that the development and improvement of oilseed markets and their byproducts could offer even more health benefits in the future, when added to other foods.

High-Pressure Technologies for the Recovery of Bioactive Molecules from Agro-Industrial Waste

Large amounts of food waste are produced each year. These residues require appropriate management to reduce their environmental impact and, at the same time, economic loss. However, this waste is still rich in compounds (e.g., colorants, antioxidants, polyphenols, fatty acids, vitamins, and proteins) that can find potential applications in food, pharmaceutical, and cosmetic industries. Conventional extraction techniques suffer some drawbacks when applied to the exploitation of food residues, including large amounts of polluting solvents, increased time of extraction, possible degradation of the active molecules during extraction, low yields, and reduced extraction selectivity. For these reasons, advanced extraction techniques have emerged in order to obtain efficient residue exploitation using more sustainable processes. In particular, performing extraction under high-pressure conditions, such as supercritical fluids and pressurized liquid extraction, offers several advantages for the extraction of bioactive molecules. These include the reduced use of toxic solvents, reduced extraction time, high selectivity, and the possibility of being applied in combination in a cascade of progressive extractions. In this review, an overview of high-pressure extraction techniques related to the recovery of high added value compounds from waste generated in food industries is presented and a critical discussion of the advantages and disadvantages of each process is reported. Furthermore, the possibility of combined multi-stage extractions, as well as economic and environmental aspects, are discussed in order to provide a complete overview of the topic.

Determination of free fatty acids in crude vegetable oil samples obtained by high-pressure processes

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Free fatty acid profile in vegetable oils was determined.

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The extraction process may influence the free fatty acid profile.

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Linoleic and oleic acids were present in higher proportions.

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The methodology applied was satisfactory for qualitative analysis.

This study determined the total acidity, fatty acids profile (TFAs), and free fatty acids (FFAs) present in sunflower and soybean oils obtained by green processes (supercritical carbon dioxide-scCO₂ and pressurized liquid extraction-PLE). The determination of the primary fatty acids responsible for product acidity can provide a higher quality product. Sunflower (scCO₂/PLE-ethanol) and soybean (PLE-ethanol/PLE-hexane) samples were evaluated. The TFAs profile was determined by gas chromatography - mass spectrometry. The total FFAs content was determined by titrimetric method. For the qualitative determination of the FFAs present in the oils, a new technique capable of repeatably identifying the main FFAs was applied, using GC/MS. The primary fatty acids (palmitic, stearic, oleic, linoleic, eicosenoic, and linolenic) were present in all samples, both as TFAs and FFAs. However, fatty acids of lesser intensity showed variations. The applied methodology provided relevant data on the FAs that cause acidity in vegetable oils obtained by green processes.

Evaluation of antioxidant capacity, fatty acid profile, and bioactive compounds from buritirana (Mauritiella armata Mart.) oil: A little-explored native Brazilian fruit

Buritirana (Mauritiella armata Mart.) is a fruit species native to the Amazon and Cerrado region, belonging to the Arecaceae family. It has high nutritional and functional potential, yet little explored. In this study, we evaluated for the first time the overall yield, behavior of total carotenoids in the extraction kinetics, fatty acid profile, bioactive compounds, and the antioxidant capacity of the oil from buritirana fractions obtained by supercritical CO₂. The highest extraction yield was found in the pulp and whole without seed at 60 °C (18.06 ± 0.40 and 14.55 ± 1.10 g 100 g^-1 of the freeze-dried sample (fdw), respectively), and in the peel at 40 °C (8.31 ± 0.73 g 100 g^-1 fdw). During the extraction kinetics, the pulp had the highest yields of oil (41.57%) and total carotenoids (8.34 mg g^-1) after 61 min at 40 °C. The antioxidant potential, fatty acid profile, and α-tocopherol content were dependent on both fraction and temperature, with oleic acid being the main fatty acid. The oil from the whole fraction without seed had the largest number (20) of identified phenolic compounds. The extraction at 60 °C reduced the relative intensity of most compounds in the whole without seed and pulp. Moreover, it increased the intensity of the compounds in the peel. These results suggest that buritirana is a good oil source with great bioactive potential to produce new products with functional claims.

Highly Efficient Deacidification Process for Camelina sativa Crude Oil by Molecular Distillation

Recovery and reuse of high-acidity vegetable oil waste (higher content of free fatty acids) is a major concern for reducing their effect on the environment. Moreover, the conventional deacidification processes are known to show drawbacks, such as oil losses or higher costs of wastewater treatment, for which it requires great attention, especially at the industrial scale. This work presents the design of a highly efficient and sustainable process for Camelina sativa oil deacidification by using an ecofriendly method, namely molecular distillation. Experimental studies were performed to identify operating conditions for removing of free fatty acids (FFA) by molecular distillation which involves the oil evaporation in high vacuum conditions. The experimental studies were supported by statistical analysis and technical-economic analysis. Response surface methodology (RSM) was employed to formulate and validate second-order models to predict deacidification efficiency, FFA concentration, and triacylglyceride (TAG) concentration in deodorized oil based on three parameters effects, validated by statistical p-value < 0.05. For a desirability function value of 0.9826, the optimal parameters of evaporator temperature at 173.5 °C, wiper speed at 350 rpm, and feed flowrate at 2 mL/min were selected. The results for process design at optimal conditions (using conventional and molecular distillation methods) showed an efficiency over 92%, a significant reduction in FFA (up to 1%), and an increase in TAG (up to 93%) in refined oil for both methods. From an economical point of view, the deacidification by molecular distillation of Camelina sativa oil is a sustainable process: no wastewater generation, no solvents and water consumption, and lower production costs, obtaining a valuable by-product (FFA).

Chemical Composition and in vitro Anti-inflammatory Activity of Wheat Germ Oil Depending on the Extraction Procedure

This study aimed to examine the chemical composition of wheat germ oil extracted by three different methods, and to evaluate its inhibitory effect on the cyclooxygenase and proteinase activities. The results showed that the contents of policosanols, tocopherols and phytosterols were affected by the extraction procedure. However, the fatty acid composition of the different oil extracts was nearly the same. Among the tested oils samples, cold pressed oil exhibited the strongest inhibitory activity against proteinase (93.4%, IC₅₀ =195.7 µg/mL) and cyclooxygenase 1 (80.5%, IC₅₀ =58.6 µg/mL). Furthermore, the cold pressed oil had the highest content of octacosanol, β-sitosterol and α-linolenic acid, suggesting that those bioactive compounds could be essential for the potent ani-cyclooxygenase activity. The present data revealed that wheat germ oil contained cyclooxygenase and trypsin inhibitors, which are the promising therapeutic target for the treatment of various inflammatory diseases. Thus, wheat germ oil might be used to develop functional foods and pharmaceutic products for the human health.

Valorization of Tropical Biomass Waste by Supercritical Fluid Extraction Technology

The inception of sustainable and cleaner extraction technology has paved the way for the innovative development of nonconventional extractions, such as supercritical fluid extraction, apart from conventional extraction counterparts. The concept of biomass waste-to-wealth for the conversion of biomass waste or by-products into value-added products for diversified applications had piqued the prominent interest of researchers and industry players, especially with the abundance of biomass resources readily available in tropical regions that have yet to be tapped into to reach their full potential. In this paper, a critical review of the developments of supercritical fluid technology from its initial inception up to commercialized scalability, including its limitations, extraction of potential tropical biomass wastes for various types of applications, such as biopesticides, bio-repellents, phenolics, and lipids for biofuel, and its role in circular bioeconomy and sustainable development approaches, are discussed in detail.