Search

The aim of this study was to provide insights into parameters that affect the oil extraction from an industrially valuable raw material (milk thistle) using green solvent supercritical CO 2. The effect of plant origin, cultivation year, and seeds storage on extraction yield has been explored. Furthermore, the effects of high-pressure unit design and initial plant material amount have been examined. Pressure (200–450 bar) and temperature (40–80 °C) have been tested to improve the recovery of essential fatty acids and phenolic compounds. Moreover, solid residues after the material pretreatment and supercritical CO 2 extraction served as the substrates for waste valorization. The characterization of obtained high-value extracts has been carried out by chromatographic (using gas chromatographs combined with mass spectrometer and flame ionization detection) and spectrophotometric assays (for total phenolic and flavonoid compounds as well as a radical scavenging ability). It was shown that the tested supercritical CO 2 extraction process parameters determined extraction kinetics and allowed the extract separation from raw milk thistle seeds and waste material (3–32 mass %) rich in linoleic acid (up to 515 mg/g) and total phenolic compounds (up to 30 mg GAE/g). [Display omitted] • Milk thistle origin, cultivation year and seeds storage determined extraction kinetic. • High-pressure unit design and amount of plant material used had an effect on the SFE process. • Variation in pressure and temperature allowed separation of up to 32 g oil / 100 g seeds. • Raw and waste seeds of milk thistle are valuable source of bioactive compounds. • Oils are rich in the essential fatty acid (linoleic acid up to 515 mg/g extract). [ABSTRACT FROM AUTHOR]

Lavandula angustifolia is one of the most widely cultivated non-food crops used in the production of essential oil; it is used in perfumery, aromatherapy, pharmaceutical preparations, and food ingredients. In this study, supercritical fluid extraction (SFE) and molecular distillation (MD) were combined, primarily to enrich scCO2 extracts with lavender oxygenated monoterpenes, avoiding thermal degradation, hydrolysis, and solvent contamination, and maintaining the natural characteristics of the obtained oils. Molecular distillation was developed for the first time for the extraction of crucial lavender fragrance ingredients, i.e., from two scCO2 extracts obtained from dry flower stems of lavender cultivated in Poland and Bulgaria. The best results for high-quality distillates were obtained at 85 °C (EVT) and confirmed that linalyl acetate content increased from 51.54 mg/g (initial Bulgarian lavender extract, L-Bg-E) and 89.53 mg/g (initial Polish lavender extract, L-Pl-E) to 118.41 and 185.42 mg/g, respectively, corresponding to increases of 2.3 and 2.1 times in both distillate streams, respectively. The distillates, light oils, and extracts from lavender were also evaluated for their antimicrobial properties by determining the minimum inhibitory concentration (MIC) by the broth microdilution method. Generally, Gram-positive bacteria and Candida spp. were more sensitive to all distilled fractions and extracts than Escherichia coli (Gram-negative bacteria). [ABSTRACT FROM AUTHOR]

In this study, potential antifungal properties of a brown alga Fucus vesiculosus were evaluated. The algal extract was obtained with the use of supercritical fluid extraction (scCO2) at a temperature of 50 °C under a pressure of 300 bar. The aqueous solution of the extract at the concentration of 0.05%, 0.2%, 0.5% and 1.0% was studied against pathogenic fungi on a liquid RB medium. This study is the first report on antifungal properties of the brown algae F. vesiculosus scCO2 extract against Fusarium culmorum and Fusarium oxysporum phytopathogens. The concentrations of the studied extract (0.5% and 1.0%) were demonstrated to have an ability to inhibit 100% growth of macroconidia within 144 h, as well as an ability to cause their total degradation. As a result of the study, the antifungal effect of fucosterol against F.culmorum was also indicated. The total macroconidia growth was inhibited by 1.0% fucosterol. Moreover, at lower concentrations (0.05–0.2%) of fucosterol, macroconidia were characterized by shorter length and structural degradation was observed. The mycelial growth of Fusarium oxysporum (Fo38) by 1% scCO2F. vesiculosus extract was analyzed at the level of 48% after 168 h of incubation, whereas 100% extract was found to be effective in F. culmorum (CBS122) and F. oxysporum (Fo38) growth inhibition by 72% and 75%, respectively after 168 h of incubation. [ABSTRACT FROM AUTHOR]

Due to their numerous health benefits associated with various diseases and anti-oxidation properties, the phenolic compounds collectively referred to as phytochemicals have attracted a lot of interest, however, a single extraction method for polyphenols has not been developed yet. Supercritical fluid extraction, a green extraction method, provides the final product without organic solvent residues. In this work the extraction of lavender was performed using supercritical carbon dioxide. A statistical experimental design based on the Box-Behnken (B-B) method was planned, and the extraction yields and total phenolic contents were measured for three different variables: pressure, temperature and extraction time. The ranges were 200–300 bar, 40–60 °C and 15–45 min. The extracts yields from scCO2 extraction were in the range of 4.3–9.2 wt.%. The highest yield (9.2 wt.%) was achieved at a temperature of 60 °C under the pressure of 250 bar after 45 min. It also corresponded to the highest total phenolic content (10.17 mg GAE/g extract). Based on the study, the statistically generated optimal extraction conditions to obtain the highest total phenolic compounds concentration from flowers of Lavandula angustifolia were a temperature of 54.5 °C, pressure of 297.9 bar, and the time of 45 min. Based on the scavenging activity percentage (AA%) of scCO2 extracts, it is concluded that the increase of extraction pressure had a positive influence on the increase of AA% values. [ABSTRACT FROM AUTHOR]

The separation of phenolic compounds by supercritical fluid extraction has been widely studied throughout the last two decades. This is evidenced by a number of publications and articles. Supercritical fluid extraction (SFE) has become thus the effective method of separating the mentioned group of compounds. On the other hand, SFE is a beneficial approach in plant waste materials utilization and reduction of environmental burdens caused by the wastes. The aim of the study is to gather and systematize available information on the phenolic compounds separation that have been reported so far as well as to evaluate whether there is one optimal supercritical fluid extraction method for the phenolic compounds. [ABSTRACT FROM AUTHOR]

Dandelion is a sustainable biomass that has occasional use in the food and pharmaceutical industry. However, commercial use of its extracts is restricted by the lack of systematic information on safety, composition, and biological activity. To broaden dandelion use, the present study brings new knowledge on extracts from dandelion seeds that could find application as safe and functional food ingredients. The employed two-step supercritical fluid extraction process, followed by the conventional extraction, enabled the separation of extracts with increased content of phenolics, tocopherols, and essential fatty acids. Those compounds were found to be the major components of dandelion extracts, reaching high values up to 799 mg GE/g, 249 mg α-TE/g, and 75%, respectively. The extracts also contained significant amounts of flavonoids (up to 20.5 mg QE/g) and pigments (chlorophyll A up to 1.0 g/kg, chlorophyll B up to 0.3 g/kg, and carotenoids up to 0.1 g/kg). This study revealed new bioproducts that express strong antioxidant (reaching IC50 values up to 132.5 μg/mL) and antimicrobial activity (with minimum inhibitory concentrations up to 80.0 μg/mL). Among the tested 23 microbial strains, the extracts exhibited the strongest activity against food-borne pathogens Micrococcus luteus and Bacillus subtilis. Furthermore, the antitumor and antiviral activity of separated dandelion biological products was evaluated. [ABSTRACT FROM AUTHOR]

The study aimed toward the development of biocompatible and biodegradable polymeric films (starch-chitosan and starch-chitosan-cyclodextrin) with biologically valuable green tea leaf extract using an environmentally friendly integrated process of supercritical fluid extraction (SFE) and supercritical solvent impregnation (SSI). The SFE-SSI process parameters were selected through the initial estimation of the SFE parameters effect (temperatures 35 and 70 °C and the addition of co-solvents ethanol, ethanol/water, and water). The present early-stage work showed that an increase in temperature increased extraction yield (from 0.9 to 4.2%) and caffeine content while it decreased polyphenolic and pigment content as well as antioxidant activity and extract loading onto films (from 7.1 to 0.1%). The addition of co-solvents to sc-CO 2 had an adverse effect on extract yield, composition, and loading. The highest recorded total phenolic, flavonoid, chlorophyll A, and caffeine content in extracts were 136.5 mg GE/g, 22.7 mg RE/g, 8.1 mg/g, and 460.0 mg/g, respectively. [Display omitted] • The SFE-SSI process for films loading with green tea leaves extracts was presented. • Starch-chitosan films with and without cyclodextrin were loaded with tea extracts. • Increase from 35 to 70 °C increased extract separation but decreased its loading. • Co-solvents had adverse effect on tea extract yield, composition, and loading. [ABSTRACT FROM AUTHOR]

The present study was focused on improving the supercritical fluid extraction process dedicated to the recovery of highly valuable extract from Silybum marianum seeds. At first, the process was tested using supercritical CO 2 at temperatures of 40 and 80 °C and pressures ranging from 100 to 300 bar. Obtained values were described using two literature models with acceptable agreement of experimental and calculated data. Further, the effect of the equipment design and process scale-up was investigated in four high-pressure units having volumes in the range from 280 mL to 40 L resulting in extraction yields up to 26 %. Based on the values of the parameters determined at the laboratory scale, the extraction process was successfully transferred to a semi-industrial scale. Finally, estimated costs for supercritical extract production in Poland for the year 2021 using a 1000 L high-pressure unit amounted to the price of 35.9 EUR per kg of extract. [Display omitted] • Kinetic of the SFE process significantly differs for four units having volumes from 0.28 to 40 L. • Three lab-scale units showed variation in extraction yield from 11.9 % to 18.0 %. • Sovova's model can be used for description the presented SFE process phenomenology. • Scale-up study showed a good agreement between laboratory and semi-industrial scale unit. • Economic evaluation indicated optimal industrial process of 3 h and extract cost of 35.9 EUR/kg. [ABSTRACT FROM AUTHOR]