Supercritical Fluid Carbon Dioxide Extraction Research Articles

A generalized neural network model for the VLE of supercritical carbon dioxide fluid extraction of fatty oils

In the present work, a neural network (NN) model was developed for the precise prediction of the phase behavior of supercritical carbon dioxide (SC-CO2) and fatty oils. A total of 678 SC-CO2 + fatty oils vapor–liquid equilibrium datasets for fatty acids, methyl and ethyl esters plus 120 data points for further accuracy examinations were used. The Cascade-Forward scheme was used as the basic architecture for the NN model calculations and predictions. Comparison between the values of the average absolute deviation of the NN model and the most important existing models showed that the NN model outperforms the other alternatives. The overall AAD for CO2 mole fractions in liquid and vapor phases were obtained to be 1.516 and 0.312%, respectively.

Supercritical fluid extraction of imidazole drugs from cosmetic and pharmaceutical products

An effective method for isolating common imidazole drugs clotrimazole (CT) and ketoconazole (KCZ) from cosmetic and pharmaceutical products based on supercritical fluid extraction (SFE) was developed. Creams, tablets and cosmetic shampoos underwent supercritical carbon dioxide fluid extraction and CT and KCZ were determined by reverse-phase high performance liquid chromatography. All supercritical fluid extractions were performed with a 10-min static step, followed by a 15 min dynamic step using acetonitrile as the modifier. After extraction by SFE, KCZ and CT were separated on a C18 column using an isocratic mobile phase that consisted of methanol/water/diethylamine/glacial acetic acid (80:20:0.3:0.2, v/v, pH 7.0) at a flow rate of 1.0 mL/min. The eluates from column were monitored by absorbance at 224 nm using a diode array detector. This developed approach was validated by assaying commercial pharmaceuticals for the routine quantification of CT and KCZ in various formulations. The calibration curves for CT and KCZ were linear over the ranges of 50-250 μg/mL and 25-250 μg/mL, respectively. The detection limits of CT and KCZ were 2.31 μg/mL and 0.42 μg/mL, respectively, and the limits of quantitation were 7.70 μg/mL and 1.40 μg/mL, respectively. These drugs contents were found to be in good agreement with the label claim values. Satisfactory extraction recoveries ranging from 90.8% to 97.2% were obtained from five replicate extractions.

Determination of antioxidative properties of Morinda citrifolia using near supercritical fluid extraction

Limited knowledge is available regarding the hydrophobic antioxidants present in the Morinda citrifolia L (Noni). Moreover, supercritical fluid carbon dioxide (SF-CO2) extraction technique is well known with many superior extraction properties. The purpose of this study was to investigate the antioxidative properties of crude extracts from the leaves, green and brown stems, and fruit of Noni plant obtained by near SF-CO2 extraction. Extracts from brown stems by near SF-CO2 extraction under high pressure and low temperature conditions afforded the highest total phenolic content (23.14 ± 1.83 mg/g) and the best reducing power (59.82 ± 6.28 ascorbic acid equivalents mg/g). It also possessed the greatest antioxidative capacities, including Trolox equivalent antioxidant capacity assay (564.52 ± 41.58 μmol/g), scavenging of 2,2-diphenyl-1-picrylhydrazyl (effective concentration : EC50 = 6.87 ± 0.14 mg/L), and superoxide radical scavenging activity (505.12 ± 26.68 SOD unit/g), which indicated that the antioxidative activity is not only due to phenolic compounds but also due to non-polar antioxidants. Extracts from the brown stems of M. citrifolia could be a significant source of antioxidants when isolated by near SF-CO2 extraction.

Direct extraction of uranium from yellow cake and ore matrices using supercritical carbon dioxide

Abstract The study demonstrates the accomplishment of single step, direct supercritical fluid carbon dioxide (SC CO2) dissolution and extraction of uranium from crude matrices viz. yellow cakes (>90%) and rock phosphate ores (70%) employing adducts of trialkyl phosphates and nitric acid, thus avoiding free acid usage and eliminating number of process steps. Rock phosphate ore was made amenable for supercritical fluid extraction (SFE) system by unique strategy of pyrohydrolytic removal of fluorine. Pressure and temperature conditions, which were found to influence uranium extraction efficiency, were optimized at 150 atm. and 323 K. Two milliliter of adduct amount was found to be adequate. Adducts of branched alkyl phosphate, tri-isoamyl phosphate and tri-ethyl hexyl phosphate (TEHP), yield better purity in comparision to straight chain tri-butyl phosphate (TBP).

Utilisation of Design of Experiments Approach to Optimise Supercritical Fluid Extraction of Medicinal Cannabis

Carbon dioxide supercritical fluid extraction (CO2 SFE) is a clean and cost-effective method of extracting cannabinoids from cannabis. Using design of experiment methodologies an optimised protocol for extraction of medicinal cannabis bud material (population of mixed plants, combined THC:CBD approximately 1:1.5) was developed at a scale of one kg per extraction. Key variables investigated were CO2 flow rate, extraction time and extraction pressure. A total of 15 batches were analysed for process development using a two-level, full factorial design of experiments for three variable factors over eleven batches. The initial eleven batches demonstrated that CO2 flow rate has the most influence on the overall yield and recovery of the key cannabinoids, particularly CBD. The additional four batches were conducted as replicated runs at high flow rates to determine reproducibility. The highest extraction weight of 71 g (7.1%) was obtained under high flow rate (150 g/min), with long extraction time (600 min) at high pressure (320 bar). This method also gave the best recoveries of THC and CBD. This is the first study to report the repeated extraction of large amounts of cannabis (total 15 kg) to optimise the CO2 SFE extraction process for a pharmaceutical product.

Determination of Polyphenols and Vitamins in Wine-Making by-Products by Supercritical Fluid Extraction (SFE)

Fruits, vegetables, cereals and their derivatives are associated with the prevention or delay of chronic degenerative diseases, being a source of important constituents able to reduce oxidative cellular stress. Vitaceae (e.g., Vitis vinifera L.) are very rich in polyphenols, sterols and vitamins that are partially transferred to wine by-products during winemaking practices. As a result, the solid waste generated by the wine industry may represent a valuable source of these active biological compounds. In this paper, in order to ennoble grape waste, high-value extracts were obtained from pomace, skins and seeds employing a simple, green and inexpensive protocol involving carbon dioxide supercritical fluid extraction (SFE). The comparison with a conventional approach based on a solid-liquid extraction, in terms of the extract antioxidant capacity and total polyphenol content, as well as extraction yield of trans-resveratrol, β-sitosterol, α-tocopherol and ascorbic acid, was carried out.

Inhibition of melanin production and promotion of collagen production by the extract of Kuji amber.

Kuji amber is fossilized tree resin of the Late Cretaceous in Japan. In this study, new biological activities of ethanol extract of Kuji amber (EtOH ext.) and supercritical carbon dioxide fluid extract of Kuji amber (scCO2 ext.) were examined. Both EtOH ext. and scCO2 ext. inhibited melanin production in B16 mouse melanoma cells and promoted collagen production in human skin fibroblast SF-TY cells. The scCO2 ext. had more potent activity than that of EtOH ext. and may depend on the efficiency of the extraction. The main new biologically active compound in Kuji amber, kujigamberol had no activities against melanin production, however, it promoted collagen production at low concentrations. A biologically active compound having a different structure, spirolactone norditerpenoid, showed both the inhibition activity against melanin production and the promotion activity of collagen production in a dose dependent manner. EtOH ext. and scCO2 ext., which include both kujigamberol and spirolactone norditerpenoid, have not only anti-allergy activity, but also inhibit melanin production and promote collagen production.

Depigmented Centella asiatica Extraction by Pretreated with Supercritical Carbon Dioxide Fluid for Wound Healing Application

Centella asiatica has been included in Thai traditional medicinal plants and recipes, as a well-established historical use as a vegetable and tonic. However, when applied in modern formulations, the progressive degradation of the plant pigments occurs, causing color-fading and color variation in the products. Depigmentation of the comminuted sample using supercritical carbon dioxide (scCO2) fluid extraction with a cosolvent was introduced as a pretreatment to solve the color-fading problem. The contents of compounds with known biological activities and the wound healing activities (antioxidant screening by DPPH and ABTS+ scavenging activities; cell migration assay; matrix metallopeptidase [MMP]-2 inhibition on human skin fibroblast; endothelial cell tube formation assay) of the C. asiatica leaf extracts obtained by conventional ethanolic extraction (CV) and pretreatment using scCO2 extraction, were determined. Total triterpenoids (madecassoside, asiaticoside B, asiaticoside, madecassic acid, terminolic acid and asiatic acid) and total triterpenoid glucosides (madecassoside, asiaticoside B and asiaticoside) were notably more abundant in the extract that had been pretreated using scCO2 than the extract obtained by CV. Moreover, the scCO2 pretreatment not only caused greater relative MMP-2 inhibition (58.48 ± 7.50% of the control), but also exhibited a higher cell migration (59.83 ± 1.85% of the initial) and number of vessels (18.25 ± 4.58) of angiogenesis in the wound healing process. Additionally, positive correlations were observed between the DPPH antioxidant activity and madecassoside content (r = 0.914, p < 0.01), as well as between the cell migration activity and asiaticoside content (r = 0.854, p < 0.05). It can be concluded that the scCO2 pretreatment of C. asiatica can eliminate color pigments from the extract and improve its in vitro wound healing activity.

Cytotoxicity of Triterpene Seco-Acids from Betula pubescens Buds.

The present study investigated the magnitude and mechanism of the cytotoxic effect on selected cancer cell lines of 3,4-seco-urs-4(23),20(30)-dien-3-oic acid (1), 3,4-seco-olean-4(24)-en-19-oxo-3-oic acid (2), and 3,4-seco-urs-4(23),20(30)-dien-19-ol-3-oic acid (3) isolated from downy birch (Betula pubescens) buds by carbon dioxide supercritical fluid extraction and gradient column chromatography. Cell viability in six human cancer lines exposed to these compounds was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was quantified by annexin V/propidium iodide staining of gastric cancer AGS and colorectal cancer DLD-1 cells. To evaluate the mechanism of apoptosis, the expression of apoptosis-related proteins was analyzed by Western blot. Compound 1 exhibited non-specific toxicity, while compounds 2 and 3 were specifically toxic to colon and stomach cancer cells. The toxicity of compounds 2 and 3 against these two cell lines was greater than for compound 1. Cleavage of caspase-8, -9, and -3 was found in AGS and DLD-1 cells treated with all three seco-acids, indicating the induction of apoptosis via extrinsic and intrinsic pathways. Therefore, triterpene seco-acids (1–3) decreased cell viability by apoptosis induction. AGS and DLD-1 cells were more susceptible to seco-acids with an oxidized C19 than normal fibroblasts. Hence, it made them a new group of triterpenes with potential anticancer activity.

Sequential Green Extraction of Caffeine and Catechins from Green Tea

Separation of caffeine and catechins from tea extracts usually requires conventional liquid-liquid extraction employing chloroform. This work was planned to improve a green extraction technique to distunguish these important chemicals from green tea. Extraction of caffeine and catechins from Turkish green tea firstly employing MAE, and then to separate these compounds from each other using a SFE method were purpose of this study. Microwave assisted extraction was applied to extract tea components from green tea then i) conventional liquid-liquid extraction or ii) supercritical carbon dioxide fluid extraction (SFE) method was charged with the effective separation of caffeine and catechins. Initially, an ethanol: water mixture was used in a close microwave system under the particuler extraction situations of green tea samples (fresh, frozen or dried) picked up in three collection periods (first, second and third collection periods). MAE of tea samples was exerted under a controlled 600 W microwave power for 4 min irradiation time at 80 oC temperature. Then MAE crude aqueous extract was divided in to two portions. The first portion was fractionated first with chloroform to distunguish caffeine then ethyl acetate for catechins. Caffeine and catechins were successfully separated. Second portion was freeze-dried and obtained lyophilized solid was used for SFE. Caffeine (3.68% extract yield) was successfully separated from catechins with SFE at 250 bar and 60°C for 180 min. Constituents of the extracts were determined (caffeine and four catechins namely EGC, EC, C, EGCG) by HPLC to evaluate the effectiveness of the separation.

Selective Extraction of ω-3 Fatty Acids from Nannochloropsis sp. Using Supercritical CO2 Extraction.

In this article, microalgae Nannochloropsis sp. was used for fatty acid (FA) extraction, using a supercritical fluid-carbon dioxide (SF-CO2) extraction method. This study investigated the influence of different pre-treatment conditions by varying the grinding speed (200–600 rpm), pre-treatment time (2.5–10 min), and mixing ratio of diatomaceous earth (DE) and Nannochloropsis sp. biomass (0.5–2.0 DE/biomass) on FAs extraction. In addition, the effect of different operating conditions, such as pressure (100–550 bar), temperature (50–75 °C), and CO2 flow rate (7.24 and 14.48 g/min) on eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) recovery, was analyzed. Experimental data evidenced that, keeping constant the extraction conditions, the pre-treatment step enhanced the FAs extraction yield up to 3.4 fold, thereby the maximum extracted amount of FAs (61.19 mg/g) was attained with the pre-treatment with a ratio of DE/biomass of 1 at 600 rpm for 5 min. Moreover, by increasing both SF-CO2 pressure and temperature, the selectivity towards EPA was enhanced, while intermediate pressure and lower pressure promoted DHA recovery. The highest amount of extracted EPA, i.e., 5.69 mg/g, corresponding to 15.59%, was obtained at 75 °C and 550 bar with a CO2 flow rate of 14.48 g/min, while the maximum amount of extracted DHA, i.e., ~0.12 mg/g, equal to 79.63%, was registered at 50 °C and 400 bar with a CO2 flow rate of 14.48 g/min. Moreover, the increased CO2 flow rate from 7.24 to 14.48 g/min enhanced both EPA and DHA recovery.

Ameliorative effect of supercritical fluid extract of Chrysanthemum indicum Linnén against D-galactose induced brain and liver injury in senescent mice via suppression of oxidative stress, inflammation and apoptosis

Ethnopharmacological relevanceChrysanthemum indicum Linne (C. indicum), a healthy food and folk medicine in China for thousands of years, has been reported to exert heat-clearing and detoxifying effects and extensively applied to treat various symptoms such as inflammation diseases, hepatitis and headache. Aim of this studyThe purpose of the present study was to investigate the protective effect of the supercritical carbon dioxide fluid extract from flowers and buds of C. indicum (CISCFE) on D-galactose-induced brain and liver damage during aging process and to illuminate the underlying mechanisms. Materials and methodsMice were orally administrated with CISCFE (100, 150 and 300 mg/kg) after injection with D-galactose. 24 h after the last administration, the blood samples, whole brain and liver tissues were collected for biochemical analysis, histological examination and western blot analysis. The body weight, spleen and thymus indexes, alanine transaminase (ALT), aspartate transaminase (AST), total antioxidant capacity (T-AOC), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), malondialdehyde (MDA) in brain and liver, interleukin-1β (IL-1β), interleukin-6 (IL-6), and necrosis factor-α (TNF-α) were detected. Besides, the expressions of Bax, Bcl-2 and cleaved caspase-3 were determined by western blot assay. ResultsThe results indicated that CISCFE effectively increased the suppressed body weight, attenuated the decline of thymus and spleen indexes, and reduced the elevated levels of ALT and AST induced by D-gal. Furthermore, CISCFE might notably alleviate D-gal-induced abnormal alterations in structure and function of brain and liver dose-dependently via renewing normal antioxidant enzymes activities (SOD, CAT, GSH-Px), reducing MDA accumulation, decreasing inflammatory cytokines productions (IL-1β, IL-6, TNF-α), as well as attenuating the increase of Bax/Bcl-2 ratio and cleaved caspase-3 activation in the liver and brain. ConclusionsTaken together, our present results suggested that CISCFE treatment could effectively mitigate the D-gal-induced hepatic and cerebral injury, and the underlying mechanism might be tightly related to the decreased oxidative stress, inflammation and apoptosis, indicating CISCFE might be an alternative and promising agent for the treatment of aging and age-associated brain and liver diseases.

Suppressive effects of the supercritical-carbon dioxide fluid extract of Chrysanthemum indicum on chronic unpredictable mild stress-induced depressive-like behavior in mice.

The aim of the present study was to explore whether the supercritical-carbon dioxide fluid extract from flowers and buds of Chrysanthemum indicum (SEC) exhibits antidepressant-like effects in a chronic unpredictable mild stress (CUMS)-induced mice model. Firstly, SEC was found to reverse a CUMS-induced decrease in the body weight gain in mice. Next, SEC was found to alleviate CUMS-induced depressive-like behavior, evidenced by the reversal of the decrease in the sucrose consumption in the sucrose preference test (SPT), the increase in the locomotor activity in the open field test (OPF), and the alleviation of immobility duration in both the forced swimming test (FST), and tail-suspension test (TST). SEC also attenuated CUMS-induced hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis by decreasing the levels of serum corticosterone and (CORT) and adrenocorticotropic hormone (ACTH), and hypothalamus corticotrophin-releasing hormone (CRH). In addition, SEC was found to suppress the expression of pro-inflammatory cytokines, including the tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in the hippocampal of CUMS mice. Interestingly, further investigations demonstrated that SEC inhibited CUMS-induced activation of the nuclear factor kappa B (NF-κB) and NOD-like receptor protein 3 (NLRP3) inflammasomes pathways but upregulated brain-derived neurotrophic factor (BDNF) expression and promoted phosphorylation of extracellular signal-regulated kinase (ERK) and cAMP-response element-binding protein (CREB) in hippocampal. In summary, SEC was able to alleviate depressive-like behavior in a CUMS-induced mice model, accompanied by inhibitory roles in the hyperactivity of the HPA axis and pro-inflammatory cytokine expression. Modulating the NF-κB/NLRP3 and BDNF/CREB/ERK pathways contributed to SEC-mediated antidepressant-like effects.

Extraction of Oil from High‐Moisture Tuna Livers by Subcritical Dimethyl Ether: A Comparison with Different Extraction Methods

Tuna livers, which are currently discarded in the fish industry, are a valuable source of marine oil rich in n‐3 polyunsaturated fatty acids (PUFAs), vitamin A, and vitamin D. In this study, subcritical dimethyl ether extraction (SDEE) is applied in the extraction of oil from high‐moisture tuna livers. Furthermore, other different extraction methods including wet reduction (WR), enzymatic extraction (EE), and supercritical carbon dioxide fluid extraction (SFE‐CO2) are used for comparisons, to assess the effect of different extraction methods on yield, oil quality, flavor (volatile compounds and sensory assessing), vitamin contents, and fatty acids composition. Compared with traditional methods, the high‐quality liver oil can be obtained with excellent yields by SDEE and SFE‐CO2, because they can prevent the oxidation of lipids, and, reduce the damage of PUFAs and vitamins effectively. Furthermore, only minor differences in volatile compounds and vitamins contents are observed between SDEE‐oil and SFE‐CO2‐oil, which is attributed to the differences in solubility to the solvents used. The oil with higher contents of vitamin A and α‐vitamin E can be obtained by SDEE. The main limitations of SFE‐CO2 are energy‐consuming due to high pressure used and the necessary pre‐treatment of freeze‐drying. However, these drawbacks could be overcome in SDEE because the pressure employed in SDEE is quite low (0.8 MPa) and the freeze‐drying is unnecessary. Therefore, SDEE would be a simple, effective, and promising technique to obtain the high quality oil rich in n‐3 PUFAs and vitamins in the fish oil industry.Practical Applications: Subcritical dimethyl ether extraction (SDEE) is a rising technology in oil extraction. It can extract oil from the high‐moisture materials without freeze‐drying under relatively low pressure. As is known, freeze‐drying is a necessary pre‐processing step in ordinary sub‐ and super‐critical fluid extraction. The high quality of oil can be obtained by SDEE, similar with the quality of the oil obtained by supercritical fluid extraction, with dramatically declined operational costs.Subcritical dimethyl ether extraction (SDEE) can extract oil from the high moisture tuna livers without freeze‐drying under relatively low pressure. Furthermore, the quality of SDEE‐oil is similar to the quality of oil obtained by supercritical carbon dioxide extraction, but substantially better than the oil obtained by wet reduction and enzymatic extraction.

Cytotoxicity of white birch bud extracts: Perspectives for therapy of tumours

Birch buds (Gemmae Betulae) are widely used in Russian and Chinese traditional medicine mainly as a diuretic and diaphoretic agent but also as an antiseptic, anti-inflammatory and analgesic. Despite the long history of therapeutic use of birch buds in folk medicine, the existing information on their chemical composition and pharmacological effects is insufficient. This circumstance warrants further study of the chemistry and pharmacology of birch buds. The present study was designed to investigate (a) the chemical composition of buds from two species of white birch and (b) the in vitro cytotoxic effect of extracts from these sources on selected tumour cells. Extracts from Betula pubescens Ehrh. and Betula pendula Roth. buds were obtained using three different methods: carbon dioxide supercritical fluid extraction (SFE), washing of exudate covering whole buds, and extraction of milled buds with diethyl ether. The chemical composition of extracts was investigated by GC-MS. Cytotoxicity was determined by MTT assay, and cell proliferation was determined by [3H]thymidine uptake in cancer cells and normal skin fibroblasts. The GC-MS investigation identified a total of 150 substances of different classes. The chemical composition of B. pubescens and B. pendula buds differed, with bud extracts from the former containing a relatively high quantity of sesquiterpenoids and flavonoids, while the main components of extracts from the latter were triterpenoids. The results of the biological assay indicated that birch bud extracts demonstrated time- and concentration-dependent and differential cytotoxicity. The highest cytotoxic activity demonstrated bud exudates and SFE extracts obtained from both Betula species. The rich chemical composition of birch buds suggests the possibility of a wider spectrum of biological activity than previously thought. Birch bud extracts could be a promising source of compounds with cytotoxic activity against various cancers.

Supercritical CO2 extracts and essential oils from Teucrium polium L. growing in Algeria: chemical composition and antioxidant activity

ABSTRACTIn this work, we studied the essential oils (EOs) obtained by hydrodistillation and lipophilic fractions extrated by carbon dioxide supercritical fluid extraction (SFE-CO2) from Teucrium polium (Lamiaceae). EOs and SFE-CO2 extracts were analyzed by GC and GC-TOFMS. EOs showed qualitative differences compared with SFE-CO2 extracts, though in both products germacrene D was the most abundant component. Notably a new EO chemotype, characterzed by germacrene D, β-eudesmol, shyobunol, and δ-cadinene, was reported. EOs along with SFE-CO2 extracts, plant powder, and solid residue after SFE were evaluated for total phenolic content (TPC) and antioxdiant activity by DPPH, FRAP, and ORAC assays. The raw plant material was the most active, followed by the solid residue after SFE-CO2 extraction. On the other hand, EO and SFE-CO2 extracts displayed weak activity. These results showed that the antioxidant compounds of T. polium are of hydrophilic nature and are not extracted or retained in the plant material after SFE-CO2 extraction.

Biological activity of Boswellia serrata Roxb. oleo gum resin essential oil: effects of extraction by supercritical carbon dioxide and traditional methods

ABSTRACTThe findings of this study suggests that chemical composition, essential oil yield, antioxidant and antimicrobial activity of Boswellia serrata oleo gum resin essential oils extracted by hydro distillation, steam distillation and supercritical fluid carbon dioxide methods vary greatly from each other. The optimum essential oil yield was obtained using hydro distillation method (8.18 ± 0.15 %). The essential oils isolated through different extraction methods contained remarkable amounts of total phenolics and total flavonoids. Essential oil isolated through supercritical fluid carbon dioxide extraction exhibited better antioxidant activity with highest free radical scavenging potential (96.16 ± 1.57 %), inhibition of linoleic acid oxidation (94.18 ± 1.47 %) and hydrogen peroxide free radical scavenging potential (68.25 ± 1.02 %). Moreover, the antimicrobial activity of essential oils was performed through well diffusion, resazurin microtiter plate and micro dilution broth assay assays. The essential oil isolated through steam distillation method revealed highest antimicrobial activity with maximum inhibition zone (24.21 ± 0.34 to12.08 ± 0.30 mm) and least MIC values (35.18 ± 0.77 to 281.46 ± 7.03 µg/mL). The comparison of chemical composition of essential oils isolated at different extraction methods have shown that the concentration of α-thujene, camphene, β-pinene, myrcene, limonene, m-cymene and cis-verbenol was higher in steam distilled essential oil as compared to hydro and supercritical fluid carbon dioxide extracted essential oils. These compounds may be responsible for the higher antimicrobial activity of Boswellia serrata oleo gum resin steam distilled essential oil.

Supercritical Fluid Extraction of Usnic Acid from Lichen of Cladonia Genus

The process of carbon dioxide supercritical fluid extraction (SFE) of secondary metabolites from the lichen of Cladonia genus is studied. The yield of solid extract during SFE with carbon dioxide is significantly higher than during the extraction with acetone, ethanol, and petroleum ether on the Soxhlet apparatus. The maximum content of the target component—usnic acid (UA)—in the extract (91%, yield—2.5% of absolutely dry raw material) is obtained under pressure of 35 MPa, temperature 40°C, and duration of the process of 40 min. Introduction of cosolvents (acetone, ethanol, methylene chloride) to carbon dioxide increases the yield of the target product to 3%.

Supercritical fluid extracts of Moringa oleifera and their unsaturated fatty acid components inhibit biofilm formation by Staphylococcus aureus

Biofilm formation by Staphylococcus aureus plays a critical role in the persistence of chronic infections because of the ability of the bacterium in biofilms to tolerate antibiotics and host defenses. S. aureus produces hemolysin, which has been implicated in the pathogenesis of sepsis and pneumonia. Hence, the inhibitions of biofilm formation and/or toxin production by S. aureus are viewed as alternative means of addressing infections. In the present study, the antibiofilm activities of Moringa oleifera extracts were examined. Of the various solvent extraction methods examined, the supercritical carbon dioxide extracts of the leaves and seeds of M. oleifera were found to efficiently inhibit biofilm formation by S. aureus. Analyses of the extracts by GC-MS revealed the presences of palmitoleic acid, oleic acid, linoleic acid, linolenic acid, cis-11-eicosenoic acid, and cis-11,14-eicosadienoic acid at concentrations of 0.01% significantly inhibited S. aureus biofilm formation. In addition, supercritical fluid extract of the leaves of M. oleifera and its major component cis-11-eicosenoic acid significantly decreased the hemolysis of human red blood cells by S. aureus. These findings suggest supercritical carbon dioxide fluid extract of M. oleifera and its unsaturated fatty acids are potentially useful for controlling biofilm formation by and the virulence of S. aureus.

Supercritical-Carbon Dioxide Fluid Extract from Chrysanthemum indicum Enhances Anti-Tumor Effect and Reduces Toxicity of Bleomycin in Tumor-Bearing Mice.

Bleomycin (BLM), a family of anti-tumor drugs, was reported to exhibit severe side effects limiting its usage in clinical treatment. Therefore, finding adjuvants that enhance the anti-tumor effect and reduce the detrimental effect of BLM is a prerequisite. Chrysanthemum indicum, an edible flower, possesses abundant bioactivities; the supercritical-carbon dioxide fluid extract from flowers and buds of C. indicum (CISCFE) have strong anti-inflammatory, anti-oxidant, and lung protective effects. However, the role of CISCFE combined with BLM treatment on tumor-bearing mice remains unclear. The present study aimed to investigate the potential synergistic effect and the underlying mechanism of CISCFE combined with BLM in the treatment of hepatoma 22 (H22) tumor-bearing mice. The results suggested that the oral administration of CISCFE combined with BLM could markedly prolong the life span, attenuate the BLM-induced pulmonary fibrosis, suppress the production of pro-inflammatory cytokines (interleukin-6), tumor necrosis factor-α, activities of myeloperoxidase, and malondiadehyde. Moreover, CISCFE combined with BLM promoted the ascites cell apoptosis, the activities of caspases 3 and 8, and up-regulated the protein expression of p53 and down-regulated the transforming growth factor-β1 by activating the gene expression of miR-29b. Taken together, these results indicated that CISCFE could enhance the anti-cancer activity of BLM and reduce the BLM-induced pulmonary injury in H22 tumor-bearing mice, rendering it as a potential adjuvant drug with chemotherapy after further investigation in the future.