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1.
《Comptes Rendus Chimie》2014,17(3):242-251
This present study was designed to evaluate the performances of five alternative solvents (alcohols: ethanol, isopropanol and terpenes: d-limonene, α-pinene, p-cymene) compared to n-hexane in rapeseed oil extraction. The extracted oils were quantitatively and qualitatively analyzed to compare the solvents’ performances in terms of kinetics, fatty acid compositions, lipid yields, and classes. Moreover, micronutrients in extracted oils were also respectively quantified by high-performance liquid chromatography (HPLC) and gas chromatography (GC). In addition, the interactions between alternative solvents and rapeseed oil have been theoretically studied with the Hansen solubility methodology to get a better comprehension of dissolving mechanisms. The results indicated that p-cymene could be the most promising solvent for n-hexane substitution with higher lipid yield and good selectivity, despite the micronutrient contents were relatively low.  相似文献   

2.
Keladi tikus (Typhonium flagelliforme (Lodd) Blume is a plant that has many benefits in - health such as anticancer, anti-inflammatory, analgesic and antihepatotoxic. This study aims to determine the antibacterial and antioxidant activity of different extracts of leaves T. flagelliforme. The agar diffusion method used in the antibacterial activity; DPPH, the FTC and the TBA method used in the antioxidant activity. The results showed the ethyl acetate, n-butanol and water fraction had antibacterial activity against Bacillus subtilis and Pseudomonas aeruginosa, while the n-hexane fraction had no activity against bacteria tested. The results of antioxidant activity by DPPH method, the FTC and the TBA showed ethyl acetate fraction was the most active (IC50 = 56.32 ppm) fraction among others.  相似文献   

3.
Toddalia asiatica (L.) Lam. (Rutaceae) has shown a broad spectrum of biological properties, such as anti-inflammatory, antioxidant, antimicrobial, anti-HIV, and anticancer properties. The present study is concerned with the separation of the main components with broad partition coefficients (KD values) from T. asiatica, using linear gradient high-speed counter-current chromatography (LGCCC) combined with an off-line two-dimensional (2D) mode. Similar to the binary gradient HPLC, the LGCCC mode is operated by the adjustment of the proportion between the mobile phase of 5:5:1:9 (v/v) (pump A) and 5:5:4.5:5.5 (v/v) (pump B) in an n-hexane/ethyl acetate/methanol/water solvent system. The off-line 2D-CCC mode was used in this study for the secondary separation of two similar KD value compounds with n-hexane/ethyl acetate/methanol/water (5:5:4:6, v/v). Notably, six coumarins, namely, tomentin (1), toddalolactone (2), 5,7,8-trimethoxycoumarin (3), mexoticin (4), isopimpinellin (5), and toddanone (6), were efficiently separated. The structures of the pure compounds were elucidated by spectral techniques and compared with the literature.  相似文献   

4.
The solubility of phthalic anhydride was measured at 283–313 K under atmospheric pressure in ethyl acetate, n-propyl acetate, methyl acetate, acetone, 1,4-dioxane, n-hexane, n-butyl acetate, cyclohexane, and dichloromethane. The solubility of phthalic anhydride in all solvents increased with the increasing temperature. The Van’t Hoff equation, modified Apelblat equation, λh equation, and Wilson model were used to correlate the experimental solubility data. The standard dissolution enthalpy, the standard entropy, and the standard Gibbs energy were evaluated based on the Van’t Hoff analysis. The experimental data and model parameters would be useful for optimizing of the separation processes involving phthalic anhydride.  相似文献   

5.
For the first time, CO2-expanded bio-based liquids were reported as novel and sustainable solvents for biocatalysis. Herein, it was found that by expansion with CO2, 2-methyltetrahydrofuran (MeTHF), and other bio-based liquids, which were not favorable solvents for immobilized Candida antarctica lipase B (Novozym 435) catalyzed transesterification, were tuned into excellent reaction media. Especially, for the kinetic resolution of challenging bulky secondary substrates such as rac-1-adamantylethanol, the lipase displayed very high activity with excellent enantioselectivity (E value > 200) in CO2-expanded MeTHF (MeTHF concentration 10% v/v, 6 MPa), whereas there was almost no activity observed in conventional organic solvents.  相似文献   

6.
The ATP-binding cassette is the major class of transporters responsible for the efflux of chemotherapeutic agents from cancer cells, resulting in treatment failures of cancer’s patients. Suaeda vermiculata Forssk. ex. J. F. Gmel. is traditionally known for its liver protective activity. The LC-MS based chemical profilings of the sequentially partitioned sub-extracts obtained from the alcoholic extract of S. vermiculata using n-hexane, chloroform, ethyl acetate, and n-butanol as fractionating solvents, identified a total of thirty six compounds. These sub-extracts were evaluated for their anti-hepatocarcinoma activity against the sensitive HepG2 and doxorubicin (DOX)-resistant, HepG-2/ADR cell lines. A mixture of doxorubicin and sub-extracts at 20 μg/ml doses were also tested for their anti-hepatocarcinoma activity. The exhibited IC50 values for the chloroform, ethyl acetate, n-hexane, and n-butanol sub-extracts, and the doxorubicin against HepG2, and HepG-2/ADR cell lines were found at 64.5, 66.8, 81.25, 125, 1.3 μg/ml, and 110.1, 91.82, 138.2, 265.7, 4.77 μg/ml levels, respectively. However, the treatment of resistant cells with 20 μg/ml of different sub-extracts in combination with the doxorubicin showed significant improvements in the doxorubicin activity against the resistant cells, and the IC50 values for DOX + chloroform, DOX + ethyl acetate, DOX + n-hexane, and DOX + n-butanol against resistant cells, were at 1.77, 2.05, 2.66, and 2.71 μg/ml levels, respectively. The IC50 values exhibited 2.69x, 2.33x, 1.79x and 1.76x-folds reversal of the sensitivity in the resistant cancer cell lines. The molecular docking studies of the compounds identified in the LC-MS chemical profilings, against three ATP-binding cassette proteins i.e., ABCB1, ABCC1, and ABCG2, showed that flavonoids as the major class of compounds responsible for reversal of the resistant cells sensitivities. The predicted binding affinity for the flavonoids against the above mentioned three ATP-binding cassette proteins’ are in the ranges of ~?8 to ?11 kcal/mol. Our results clearly indicate that the presence of flavonoids, as the major class of compounds in the S. vermiculata is responsible for the chemosensitization of the resistant HCC-cell lines. Moreover, the structures, 21 (5‐O‐methyl visamminol), 22 (N-trans-feruloyl tyramine), 27 (atractylenolide-III), and 32 (ginsenoside-Rh2) were also identified among the potential ATP-binding cassette’s modulators during the current study. These observations put the S. vermiculata in perspective with the traditionally claimed liver protective efficacy of the plant.  相似文献   

7.
Ovatodiolide (Ova), found in the plant Anisomeles indica (AI), has been reported to have an anti-proliferation effect in various cancer cells. However, little information is available regarding the anti-cancer effect of Ova in human gastric cancer cells. In this study, we investigated the inhibitory effects and the mechanisms of action responsible for these effects on human AGS cell lines from a newly developed purification technique for Ova from AI extract. Extract obtained at the optimum condition of 95% ethanol extraction of AI was sequentially partitioned by using different polarity solvents. Enriched content of Ova (35.9% purity) from the n-hexane fraction was then applied to the purification by using centrifugal partition chromatography (CPC) in a two-phase solvent system consisting of n-hexane:ethyl acetate:methanol:water (1.0:1.0:1.0:1.0, v/v/v/v) to reach purity over >95.0%. In evaluation of the anti-proliferation effect on AGS cells, Ova induced cell apoptosis with IC50 values of 13.02 and 6.18 μM at 24 and 48 h, respectively, and arrested the cells at the G2/M phase. Quantification of Bax/Bcl2 mRNA expressions using qPCR showed a 2.5-fold increase in the Ova (5 μM)-treated cells at 48 h than in the control group. Specific protein expression data warrant further research to further confirm the proposed Ova-induced apoptotic pathway in AGS cells.  相似文献   

8.
The coupled reaction of methyl acetate and n-hexane was carried out over a HZSM-5 catalyst. In addition to a thermal coupling effect, systematic variations in the product distribution were also observed in the coupled system. The bezene-toluene-xylene (BTX) selectivity was remarkably improved while the H2, CO, and CO2 selectivity decreased. Rapid deactivation of the catalyst was observed, caused by the extremely high reactivity of methyl acetate, which was alleviated after adding n-hexane. These results indicated that a coupling effect exists in this system. A detailed pathway for the coupled system is suggested based on the analysis of the surface species, carbonaceous species deposited on the catalyst, as well as the product selectivity changes. The good match between the “hydrogen deficiency” of methyl acetate and the “hydrogen richness” of n-hexane is consistent with the observed coupling effect.  相似文献   

9.
Leaves and aerial parts of Malva neglecta Wallr. have been traditionally used in Anatolia for the treatment of pain, inflammation, hemorrhoids, renal stones, constipation, and infertility. This study investigated the effects of M. neglecta leaves in a rat endometriosis model. The dried plant material was extracted with n-hexane, ethyl acetate, and methanol, successively. Experimental endometriosis was surgically induced in six-week-old female, non-pregnant, Wistar albino rats by autotransplant of endometrial tissue to the abdominal wall. After twenty-eight days, rats were evaluated for a second laparotomy. Endometrial foci areas were assessed, and intraabdominal adhesions were scored. Rats were divided into five groups as control, n-hexane, ethyl acetate, methanol, and aqueous extracts, as well as reference. At the end of the treatment, all rats were sacrificed and endometriotic foci areas and intraabdominal adhesions were re-evaluated and compared with the previous findings. Moreover, peritoneal fluid was collected to detect tumor necrosis factor- α (TNF-α), vascular endothelial growth factor (VEGF), and interleukin-6 (IL-6) levels, and cDNA synthesis, and a quantitative real-time polymerase chain reaction (PCR) test was done. The phytochemical content of the most active extract was determined using High-Performance Liquid Chromatography (HPLC). Both endometrial volume and adhesion score decreased significantly in the group treated with methanol extract. In addition, significant decreases were observed in TNF-α, VEGF, and IL-6 levels in animals administered methanol extract. HPLC results showed that the activity caused by the methanol extract of M. neglecta was due to the polyphenols. Taken together, these novel findings indicate that M. neglecta may be a promising alternative for the treatment of endometriosis.  相似文献   

10.
An economical method for isolation of dioscin from Dioscorea nipponica Makino by high-speed counter-current chromatography (HSCCC) was successfully developed by using a UNIFAC mathematical model coupled with computer-aided counter-current chromatography solvent-selection software (CCC-SSS) for separate preparation of the components of the solvent system (i.e., the stationary and mobile phases). The solvent system n-hexane–ethyl acetate–ethanol–water 2:5:2:5 (v/v) was selected to demonstrate the feasibility of the approach. A comparative study was also carried out on different methods for preparation of the solvent system, namely conventional preparation of the mobile and stationary phases together in the same vessel and the method developed for separate preparation of the phases. The results indicated that purity and recovery of dioscin were no different when solvent systems prepared by the different methods were used for HSCCC separation. Much less n-hexane, ethyl acetate, and ethanol was used when the mobile and stationary phases were prepared separately, however. This was not only environmentally sensible, but also enabled conservation of resources. Use of the UNIFAC mathematical model combined with the CCC-SSS technique for separate preparation of the components of the solvent system in HSCCC is reported and explained. It is a simple and economical means of isolating pure dioscin from Dioscorea nipponica Makino.  相似文献   

11.
Background: Ponciri Fructus, a crude drug consisting of the dried immature fruits of Poncirus trifoliata (L.) Raf., is a popular folk medicine used for the treatment of allergy and gastrointestinal disorders in Korea and China. In this study, the anti-adipogenic activity of extracts and isolated compounds were evaluated using 3T3-L1 preadipocytes. Methods: Dried immature fruits were extracted and fractionated into n-hexane, ethyl acetate (EtOAc), n-butanol and water-soluble fractions. The ethanol extract and fractions were tested for anti-adipogenic activity in the 3T3-L1 cell line. The active fractions (n-hexane and EtOAc fractions) were further subjected to chromatographic techniques to isolate and identify active compounds. Furthermore, the isolated compounds were evaluated for their anti-adipogenic activity. Results: Altogether, seven compounds, including two flavonoids, one phytosteroid and four coumarin derivatives, were isolated. Ethanol extract, n-hexane fraction, EtOAc fraction and three isolated compounds (phellopterin, oxypeucedanin and poncirin) showed significant anti-adipogenic activity as observed by reduced lipid deposition in differentiated 3T3-L1 cells. Further, oxypeucedanin downregulated the key adipogenic markers, such as peroxisome proliferator-activated receptors proteins γ (PPAR-γ), sterol response element binding proteins-1 (SREBP-1), CCAAT/enhancer binding proteins-α (C/EBP-α), adipocyte-specific lipid binding proteins (FABP-4), adipocyte fatty acid binding proteins (aP2), lipoprotein lipase (LPL) and leptin. Conclusion: This study indicated that the ethanol extract, hexane fraction and ethyl acetate fraction of P. trifoliata fruits possess strong anti-adipogenic activity, containing the active compounds such as phellopterin, oxypeucedanin and poncirin. Further research is recommended to explore their efficacy and safety in animal and clinical models.  相似文献   

12.
Using natural products as antioxidant agents has been beneficial to replace synthetic products. Efforts have been made to profile the antioxidant capacities of natural resources, such as medicinal plants. The polyphenol content of Himalayan rhubarb, Rheum emodi wall, was measured and the antioxidant activity was determined using DPPH and ABTS+ assay, and the oxidative stress was assessed using SOD enzymatic assay. Five different solvent fractions, n-hexane, n-butanol, ethyl acetate, dichloromethane, and water, were used for screening the antioxidant capacity in effort to determine the optimum extraction solvent. The total phenolic contents for R. emodi fractions ranged from 27.76 to 209.21 mg of gallic acid equivalents (GAE)/g of dry weight. DPPH and ABTS+ assay results are presented into IC50 values, ranged from 21.52 to 2448.79 μg/mL and 90.25 to 1718.05 μg/mL, respectively. The ethyl acetate fraction had the highest antioxidant activity among other fractions. Also, n-butanol and water fractions showed significantly lower IC50 values than the positive control in DPPH radical scavenging activity. The IC50 values of SOD assay of fractions ranged from 2.31 to 64.78 μg/mL. A similar result was observed with ethyl acetate fraction showing the highest SOD radical scavenging activity. The study suggests that the ethyl acetate fraction of R. emodi possess the strongest antioxidant activity, thus the most efficient in extracting antioxidant contents. Moreover, a highly significant correlation was shown between total polyphenol content and antioxidant activity screening assays. The compounds related to the antioxidant activity of R. emodi were identified to myricitrin, myricetin 3-galloyl rhamnoside, and myricetin, which have not been reported in studies about R. emodi before.  相似文献   

13.
The solubility of coenzyme Q10 in ethyl acetate, n-hexane, 1-butanol, 1-propanol, 2-propanol and ethanol in the temperature range 270.15–320.15 K, under atmospheric pressure, was measured by a gravimetric method and compared with the data predicted using the conductor like screening model for realistic solvation (COSMO-RS) method. The results show that the solubilities of coenzyme Q10 in the above solvents increase with temperature. The temperature dependences of predicted solubilities were consistent with the experimental data. The experimental data were correlated with the Apelblat equation. At the same temperature, the order of increasing solubility is ethyl acetate > n-hexane > 1-butanol > 1-propanol > 2-propanol > ethanol.  相似文献   

14.
The usefulness of biphasic aqueous-organic solvent systems for pepsin-catalyzed synthesis of model peptidesZ-X-Phe-Phe-OMe (X=Ala, Gln, Leu) has been demonstrated by coupling the correspondingZ-X-Phe-OH with H-Phe-OMe. The influence of various organic solvents on pepsin activity was examined. Some examples are given for the influence of nucleophile and enzyme concentration, bufferpH and organic solvent portion on product yield. Tetrachloromethane and mixtures of ethyl acetate/n-hexane proved to be especially useful allowing syntheses in good yields and within comparatively short reaction times of 2–6 hours.  相似文献   

15.
Pulicaria jaubertii is a medicinal herb that alleviates inflammations and fever. Chromatographic separation, phytochemical characterization, and in vitro biological activities of the plant n-hexane extract were conducted for the first time in this study. Six compounds were isolated for the first time from the n-hexane fraction of Pulicaria jaubertii aerial parts and were identified on the bases of NMR and MS analyses as pseudo-taraxaterol (1), pseudo-taraxasterol acetate (2), 3β-acetoxytaraxaster-20-en-30-aldehyde (3), calenduladiol-3-O-palmitate (4), stigmasterol (5), and α-tocospiro B (6). Compound (6) was a rare tocopherol-related compound and was isolated for the first time from family Asteraceae, while compound (3) was isolated for the first time from genus Pulicaria. The total alcoholic extract and n-hexane fraction were tested for their anti-inflammatory, antidiabetic, and cytotoxic activities. The n-hexane fraction has dose dependent red blood cells (RBCs) membrane stabilization and inhibition of histamine release activities with IC50: 60.8 and 72.9 µg/mL, respectively. As antidiabetic activity, the alcoholic extract exerted the most inhibition on the activity of yeast α-glucosidase, with an IC50: 76.8 µg/mL. The n-hexane fraction showed cytotoxic activity against hepatocarcinoma (HepG-2), breast carcinoma (MCF-7), and prostate carcinoma (PC-3) cell lines with IC50: 51.8, 90.8 and 62.2 µg/mL, respectively. In conclusion, the anti-inflammatory effect of Pulicaria jaubertii might be attributed to the triterpenoid constituents of the n-hexane extract of the plant.  相似文献   

16.
The distribution function of the energy of adsorption (heterogeneity function, χ) was studied for porous polymers using inverse gas chromatography. The heterogeneity functions to-wards n-hexane, n-butanol, and ethyl acetate probes were obtained for four porous polymers prepared by polymerization of styrene and divinylbenzene. The value of c for the polar surface depends on the choice of the test sorbate. The possibility of comparing surface heterogeneity of various porous polymers using the parameter χ was shown.  相似文献   

17.
The distribution ratios of TTA and its scandium chelate between aqueous perchlorate solutions (μ=0.1) and 15 ester solvents including ethyl acetate were determined at 25°. A good correlation was found between the distribution coefficients of TTA and the “solubility parameter” of the ester solvents. The relationship between the distribution coefficients of the scandium chelate (PM) and those of TTA (PHA) was shown to be, log PM=n log PHA+ const. The distribution of this chelate into another ester can thus be predicted.  相似文献   

18.
Aphis craccivora Koch is a polyphagous and major pest of leguminous crops causing significant damage by reducing the yield. Repeated application of synthetic insecticides for the control of aphids has led to development of resistance. Therefore, the present study aimed to screen the insecticidal activity of root/stem extracts/fractions, and pure molecules from Cissampelos pareira Linnaeus against A. craccivora for identification of lead(s). Among root extract/fractions, the n-hexane fraction was found most effective (LC50 = 1828.19 mg/L) against A. craccivora, followed by parent extract (LC50 = 2211.54 mg/L). Among stem extract/fractions, the n-hexane fraction (LC50 = 1246.92 mg/L) was more effective than the water and n-butanol fractions. Based on GC and GC-MS analysis, among different compounds identified in the n-hexane fraction of root and stem, ethyl palmitate (known to possess insecticidal activity) was present in the highest concentration (24.94 to 52.95%) in both the fractions. Among pure molecules, pareirarineformate was found most effective (LC50 = 1491.93 mg/L) against A. craccivora, followed by cissamine (LC50 = 1556.31 mg/L). Parent extract and fractions of C. pareira possess promising activity against aphid. Further, field bio-efficacy studies are necessary to validate the current findings for the development of botanical formulation.  相似文献   

19.
《Tetrahedron: Asymmetry》1999,10(19):3759-3767
Resolutions of (RS)-4-cyano-4-(3,4-dimethoxyphenyl)-4-isopropyl-1-butanol 1 using various enzymes were performed. Among them, Pseudomonas fluorescens resolved it with moderate stereoselectivity (E=13) and reacted faster with the (S)-enantiomer. To optimize enzyme-catalysed reaction conditions for the resolution, the effect of solvents and additives was studied. In n-hexane:ethyl acetate (9:1), both reaction rate and selectivity were high. When pyridine, potassium carbonate and molecular sieves were used as additives, the enantiomeric excess of the (R)-enantiomer was 99, 99 and 98% at 52–60% conversion, respectively. However, in diisopropyl ether, the enantiomeric excess of unreacted alcohol (R)-1 was up to 99% at 70% conversion without additives.  相似文献   

20.
Corradini  D.  Grego  S.  Liburdi  K.  Marinari  S.  Tonci  M. 《Chromatographia》2006,63(13):S11-S16

This paper reports the results of a study carried out to evaluate the potentiality of combining selective solvent extraction and linear gradient elution reversed-phase high performance liquid chromatography (RP-HPLC) for characterizing soil organic matter on the basis of polarity of its constituting organic compounds. Such approach comprises the sequential extraction of soil organic matter with organic solvents of increasing polarity in a Soxhlet extractor and the subsequent separation of each extract by RP-HPLC. Accordingly, each soil sample has been subjected to cycles of sequential extraction with n-hexane, dichloromethane, ethyl acetate, and methanol. Each sample extracted by one of the four solvents have been dried in a rotary evaporator device at 40°C and then dissolved again in the proper volume of extraction solvent to obtaining sample solutions of concentration ranging from 5.0 to 15 mg ml−1. These sample solutions have been subjected to RP-HPLC separation using a Supelcosil LC-ABZ column that has been eluted by a linear acetonitrile gradient in water, having the same profile for all samples. The study has evidenced the possibility of producing highly repeatable chromatographic profiles, which are correlated to the polarity of organic solvents employed for extracting the organic matter in the Soxhlet extractor.

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