Efficient new method for extraction and isolation of three flavonoids from Patrinia villosa Juss. by supercritical fluid extraction and high-speed counter-current chromatography

Supercritical fluid extraction (SFE) of orotinin, orotinin-5-methyl ether and licoagrochalcone B from Patrinia villosa was performed. The optimization of parameters including pressure, temperature, modifier and sample particle size on yield was carried out using an analytical-scale SFE system. The process was then scaled up by 100 times using a preparative SFE system under the optimized conditions of 25 MPa, 45 degrees C, a sample particle size 40-60 mesh and modified CO2 with 20% methanol. The yield of the preparative SFE was 2.82% (crude extract I) and the combined yield of orotinin, orotinin-5-methyl ether and licoagrochalcone B was 0.82 mg/g of dry sample mass. Then the crude extract I was re-dissolved in methanol and methanol soluble fraction (crude extract II, 0.17%) was obtained, which was successfully isolated and separated by a preparative high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (5:6:6:6, v/v/v/v) by increasing the flow-rate of the mobile phase stepwise from 1.0 to 2.0 ml/min after 3 h. The target compounds isolated and purified by HSCCC were analyzed by high performance liquid chromatography. The separation produced total of 38.2 mg of orotinin at 99.2% purity, 19.8 mg of orotinin-5-methyl ether at 98.5% purity and 21.5 mg of licoagrochalcone B at 97.6% purity from 400 mg of the crude extract in a one-step separation. The recoveries of orotinin, orotinin-5-methyl ether and licoagrochalcone B were 91.1, 91.6 and 90.3%, respectively, and the chemical structure identification was carried out by UV, IR, MS, 1H NMR and 13C NMR.     

Supercritical fluid extraction of cynaropicrin and 20-hydroxyecdysone from Leuzea carthamoides DC

Leuzea carthamoides is an adaptogenic plant containing biologically active compounds as ecdysteroids and guaianolide-type sesquiterpene lactones, conventionally extracted from the plant with ethanol. It may be a potential source of the mentioned natural compounds. Ethanol-modified near-critical CO(2) was used as selective solvent with the aim to increase the level of 20-hydroxyecdysone in the extract from L. carthamoides roots and to remove selectively cynaropicrin, a sesquiterpene lactone of bitter taste, from the leaves. The extraction conditions were varied (pressure 20-28 MPa, temperature 40-60 degrees C, ethanol concentration in the solvent 0-7.1%) and the extraction yield and extract composition were compared with the results of ethanolic extraction. The supercritical fluid extraction (SFE) from finely powdered plant was controlled by phase equilibrium. Cynaropicrin was quantitatively removed from the leaves where 89% of 20-hydroxyecdysone was retained. The extraction yield of 20-hydroxyecdysone from roots with ethanol-modified CO(2 )was lower by 30% than with ethanol but its concentration in the extract was higher by 67%.     

高温煤焦油的超临界萃取分馏研究

采用正戊烷溶剂,在超临界状态下,于220℃和5MPa~15MPa循序升压条件下,将高温煤焦油萃取分馏为10个液相窄馏分和1个固相沥青产物;切割深度达78.36%,萃余沥青收率为21.64%,明显低于常规蒸馏沥青收率。研究发现,所用高温煤焦油的初馏分萃取收率最高,随着萃取压力的增加,较低压力段一次萃取液相馏分的收率迅速减少;压力达到10 MPa,液相馏分总收率趋于峰值。元素分析和色质联用分析数据表明,随着萃取压力的增加,一次萃取获得窄馏分的碳氢原子比逐渐增加,平均环数和相对分子质量均逐渐增大,萃取馏分逐渐变重。     

Preparation and characterization of fragrance by extracting the essential oils from different raw materials

The extraction is a simple process and it is widely used to extract the fragrances in fragrance industries from essential oils. There are number of compounds (i.e. flowers, oils, leaves etc.) from which we can prepare the fragrance by extracting the essential oils from them. In this work, we have prepared the fragrance from the essential oils by the liquid-liquid extraction process, where the essential oil presented as the concentrated hydrophobic liquid containing volatile aroma compounds. We used the combination of Gas chromatography and Mass spectrometry (GC/MS) characterization techniques to make our product more useful, convenient and compitative with the other fragrance available in the market. This study would be helpful to understand the preparation of the fragrance from the concentrated hydrophobic liquid type essential oils which contains volatile aroma compounds by using a significant liquid-liquid extraction process.     

Essential oil composition of Nepeta satureioides from Iran

The essential oil of Nepeta satureioides Boiss. from Iran was isolated by hydrodistillation in yield of 0.06% (w/w). The chemical composition of the essential oil was analyzed by GC and GC-MS. Forty-five compounds accounting for 97.4% of the total oil were identified. The major components were linalool (23.8%), (Z,E)-farnesol (14.7%), linalyl acetate (11.1%), β-caryophyllene (6.6%), lavandulol acetate (6.6%), caryophyllene oxide (6.4%), and (Z)-β-farnesene (3.4%). Oxygenated terpenoids were the main group of compounds. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 144–145, March–April, 2006.     

Supercritical Carbon Dioxide Extraction of Four Medicinal Mediterranean Plants: Investigation of Chemical Composition and Antioxidant Activity

With everyday advances in the field of pharmaceuticals, medicinal plants have high priority regarding the introduction of novel synthetic compounds by the usage of environmentally friendly extraction technologies. Herein, a supercritical CO₂ extraction method was implemented in the analysis of four plants (chamomile, St. John’s wort, yarrow, and curry plant) after which the non-targeted analysis of the chemical composition, phenolic content, and antioxidant activity was evaluated. The extraction yield was the highest for the chamomile (5%), while moderate yields were obtained for the other three plants. The chemical composition analyzed by gas chromatography-high-resolution mass spectrometry (GC-HRMS) and liquid chromatography-high-resolution mass spectrometry (LC-HRMS) demonstrated extraction of diverse compounds including terpenes and terpenoids, fatty acids, flavonoids and coumarins, functionalized phytosterols, and polyphenols. Voltammetry of microfilm immobilized on a glassy carbon electrode using square-wave voltammetry (SWV) was applied in the analysis of extracts. It was found that antioxidant activity obtained by SWV correlates well to 1,1-diphenyl-2-picrylhidrazine (DPPH) radical assay (R² = 0.818) and ferric reducing antioxidant power (FRAP) assay (R² = 0.640), but not to the total phenolic content (R² = 0.092). Effective results were obtained in terms of activity showing the potential usage of supercritical CO2 extraction to acquire bioactive compounds of interest.     

Extraction of atrazine and its metabolites using supercritical fluids and enhanced-fluidity liquids

Supercritical fluid and enhanced-fluidity liquid extractions are performed on spiked sediment samples containing atrazine (ATRA) and five of its metabolites including desisopropyldesethylatrazine, desethylhydroxyatrazine (DEHA), desisopropylatrazine, desethylatrazine, and hydroxyatrazine (HA). The hydroxylated metabolites are of particular interest because of their increased water solubility and the fact that their high polarity makes them difficult to analyze. Soxhlet extractions using methanol are conducted for the purpose of comparison. Results of the extractions show that the hydroxy-containing metabolites of ATRA are not effectively extracted with supercritical CO2 alone. The solvating or desorbing power of carbon dioxide appears too low to extract HA and DEHA. The extraction recoveries of the hydroxylated metabolites increase when enhanced-fluidity liquid mixtures of methanol/CO2 are used, and these rates increase with the methanol concentration. Enhanced-fluidity ternary liquid mixtures of H2O/methanol/CO2 yield the best recoveries for these compounds. ATRA recoveries are equally effective when using supercritical CO2 or enhanced-fluidity mixtures. The other nonhydroxy-containing metabolites require the increased solvent strength of either large percentages of methanol in CO2 or ternary mixtures of H2O, methanol, and CO2 for high recoveries. Recoveries with enhanced-fluidity liquid ternary mixtures are better than the recoveries from Soxhlet for all the compounds in the study.     

Comparing the effect of sub-critical water extraction with conventional extraction methods on the chemical composition of Lavandula stoechas

The volatile extract composition of Lavandula stoechas flowers obtained by hydrodistillation (HD), subcrtical water extraction (SbCWE) and organic solvent extraction under ultrasonic irradiation (USE) were estimated by gas chromatography-mass spectrometry (GC-MS). One hundred and twenty four components were detected in SbCWE extracts while 94 and 65 signals were gained from HD and USE extracts, respectively. Most of the constituents were identified. The major compounds in all three extracts were fenchon, camphor, myrtenyl acetate, myrtenol and 1,8-cineol, but they differ in quantitatively. The total monoterpene hydrocarbons are higher in HD and USE extracts than those of SbCWE extract. However, SbCWE extract had higher concentration of light oxygenated compounds which contributes to the fragrance of the oil in a major extension. Heavy-oxygenated compounds was also in higher abundance in SbCWE extract (9.90%) than those of HD and USE extracts (3.19 and 4.78%, respectively). Effect of temperature on the extraction yield of SbCWE was investigated and while oil yield was increasing with an increase in temperature, a decrease in the extraction ability of sub-critical water toward the more polar compounds such as, 1,8-cineol, camphor and fenchon, was observed. Kinetic studies shown that SbCWE is clearly quicker than conventional alternatives. Most of components of volatile compounds were extracted at 15min.     

Analysis of xanthohumol and isoxanthohumol in different hop products by liquid chromatography-diode array detection-electrospray ionization tandem mass spectrometry

An analytical methodology based on the sample extraction with methanol/formic acid by ultra-sonication and subsequent analysis by high-performance liquid chromatography with diode array detection is proposed for the determination of xanthohumol (XN) and isoxanthohumol (IXN) in different hop products. The identity of the compounds was confirmed by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry in positive ion mode. The performance of the method was assessed by the evaluation of parameters such as absolute recovery, repeatability, linearity and limits of detection and quantitation. This methodology was applied to investigate the impact of the extraction process of the hop products on the amount of xanthohumol and isoxanthohumol. The ethanolic extract revealed to be the hop product richest in xanthohumol (3.75+/-0.05 g/100 g) relatively to the pellets (0.62+/-0.01 g/100 g) and supercritical CO2 extract (0.089+/-0.001 g/100 g).     

Thermolysis of 1-(1-aryl-1-bromomethyl)cyclopropyl bromides: a reinvestigation

Two compounds, the (Z)- and (E)-isomers of 2,4-dibromo-1-p-tolyl-1-butene 2a and 3a, respectively, were isolated in 65% total yield when 1-(1-bromo-1-p-tolylmethyl)cyclopropyl bromide (1a) was heated at 150 degrees C for 1 h. 1,1-Dibromo-2-p-tolylcyclobutane (4a), previously reported to be the only product in this reaction, was not detected. The phenyl analogue of 1a reacted similarly and gave the (Z)- and (E)-isomers of 2,4-dibromo-1-phenyl-1-butene 2b and 3b, respectively, in 60% yield. A rationale for the reaction is presented.     

褐煤在离子液体1-丁基-3-甲基咪唑氯盐中热溶及热溶产物的分离与分析

基于离子液体对煤的高效解聚性能,对先锋褐煤(XL)、锡林郭勒褐煤(XLGL)和胜利褐煤(SL)在离子液体1-丁基-3-甲基咪唑氯盐([Bmim]Cl)中的热溶性能进行了研究.同时,对XL在离子液体[Bmim]Cl中的热溶产物进行了分离,并对分离所得各组分进行了分析表征来研究褐煤的结构信息.研究发现,在相同条件下离子液体[Bmim]Cl对不同褐煤的萃取性能显著不同,其顺序为XL>SL>XLGL.先锋褐煤离子液体热溶物可分离为丙酮可溶物、吡啶可溶物和吡啶不溶物,其中,丙酮可溶物(AS)为15.9%、吡啶可溶物(PS)为56.0%、吡啶不溶物(PI) 为28.1%.分析表明,丙酮可溶物中含有长链的脂肪化合物及部分三环、四环等芳香化合物,吡啶可溶物和吡啶不溶物中大多以三环及五环芳香化合物的形式存在.     

金鸡钠碱催化烯胺的不对称C-亚磺酰化反应

以金鸡钠碱催化烯胺的不对称C-亚磺酰化反应,产物(E,Z)-N-苄氧羰基-2-苯亚磺酰基-1-苯基丙烯胺[(E,Z)-4],收率71%,立体选择性E:Z=3:2,其中(E)-4和(Z)-4的对映选择性分别为75%ee和93%ee。     

Pressurized liquid extraction of ginger (Zingiber officinale Roscoe) with bioethanol: an efficient and sustainable approach

To develop an efficient green extraction approach for recovery of bioactive compounds from natural plants, we examined the potential of pressurized liquid extraction (PLE) of ginger (Zingiber officinale Roscoe) with bioethanol/water as solvents. The advantages of PLE over other extraction approaches, in addition to reduced time/solvent cost, the extract of PLE showed a distinct constituent profile from that of Soxhlet extraction, with significantly improved recovery of diarylheptanoids, etc. Among the pure solvents tested for PLE, bioethanol yield the highest efficiency for recovering most constituents of gingerol-related compounds; while for a broad concentration spectrum of ethanol aqueous solutions, 70% ethanol gave the best performance in terms of yield of total extract, complete constituent profile and recovery of most gingerol-related components. PLE with 70% bioethanol operated at 1500 psi and 100 °C for 20 min (static extraction time: 5 min) is recommended as optimized extraction conditions, achieving 106.8%, 109.3% and 108.0% yield of [6]-, [8]- and [10]-gingerol relative to the yield of corresponding constituent obtained by 8h Soxhlet extraction (absolute ethanol as extraction solvent).     

SFE-CO2 extract from Typhonium giganteum Engl. tubers, induces apoptosis in human hepatoma SMMC-7721 cells involvement of a ROS-mediated mitochondrial pathway

Typhonium giganteum Engl. (BaiFuzi) is one of the herbs commonly used in traditional Chinese medicine against cancer. In our previous studies, 37 compounds were identified the SFE-CO(2) (supercritical fluid extraction with CO(2)) extract by GC-MS, including the four major components [β-sitosterol (40.22%), campesterol (18.45%), n-hexadecanoic acid (9.52%) and (Z,Z)-9,12-octadecadienoic acid (8.15%)]. The anti-cancer mechanisms of the SFE-CO(2 )extract from T. giganteum Engl. tubers have not been reported as yet. In this paper, the molecular mechanisms of the SFE-CO(2) extract-mediated apoptosis in SMMC-7721 cells were further examined. SFE-CO(2) extract inhibited the growth of SMMC-7721 cells in a time- and dose-dependent manner, arrested the cell cycle in the S phase and G2/M phase, and induced apoptosis. In addition, reactive oxygen species (ROS) increase, reduction of mitochondrial membrane potential, a rise in intracellular calcium levels were found in SMMC-7721 cells after treated with the extract. Western blot analysis showed that the extract caused down-regulation of Bcl-2 expression, and up-regulation of Bax expression. Moreover, caspase-3 and caspase-9 protease activity significantly increased in a dose-dependent manner. Collectively, our results showed that the SFE-CO(2) extract from T. giganteum Engl. tubers induces apoptosis in SMMC-7721 cells involving a ROS-mediated mitochondrial signalling pathway.     

Syntheses of highly unsaturated isocyanides via organometallic pathways

The carbon carbon coupling reaction by nucleophilic attack of (CO)(5)Cr(CN-CF=CF(2)) 1 by lithium or Grignard compounds 2a-i yields the isocyanide complexes (CO)(5)Cr(CN-CF=CF-R) 3a-i (a R = CH=CH(2), b R = CH=CF(2), c R = C≡CH, d R = C≡C-SiMe(3), e R = C≡C-Ph, f R = C≡C-C(6)F(4)OMe, g R = C≡C-C(6)H(3)(CF(3))(2), h R = C(6)F(5), i R = C(6)H(3)(CF(3))(2)) as mixtures of E and Z isomers. The dinuclear complexes 5a-c are obtained from the reaction of 1 with the dilithio or dimagnesium compound 4a-c as the Z,Z-, E,Z- and E,E-isomers, respectively. (CO)(5)Cr(CN-CF=CF-C≡C-C≡C-CF=CF-NC)Cr(CO)(5)7 is obtained as a mixture of Z,Z-, Z,E- and E,E-isomers from (CO)(5)Cr(CN-CF=CF-C≡C-H 3d by Eglington-Glaser coupling. (CO)(5)Cr(CN-CF=CF-C≡C-CF=CF-NC)Cr(CO)(5)6 and (CO)(5)Cr(CN-CF=CF-C=C-C≡C-CF=CF-NC)Cr(CO)(5)7 react with octacarbonyldicobalt forming the cluster compounds Z,Z-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-CF=CF-NC)Cr(CO)(5)}Co(2)(CO)(6)] Z,Z-8, E,Z-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-CF=CF-NC)Cr(CO)(5)}Co(2)(CO)(6)] E,Z-8 and E,E-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-CF=CF-NC)Cr(CO)(5)}Co(2)(CO)(6)] E,E-8 and Z,Z-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-C≡C-CF=CF-NC)Cr(CO)(5)}{Co(2)(CO)(6)}(2)] Z,Z-9, E,Z-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-C≡C-CF=CF-NC)Cr(CO)(5)}{Co(2)(CO)(6)}(2)] E,Z-9 and E,E-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-C≡C-CF=CF-NC)Cr(CO)(5)}{Co(2)(CO)(6)}(2)] Z,Z-9, respectively. The crystal and molecular structures of E-3d, Z-3h, Z,Z-8, E,Z-8 and Z,Z-9 were elucidated by single-crystal X-ray crystallography.     

正戊烷异构化催化剂的研究

20世纪80年代以来,由于环保的要求,C5/C6烷烃异构化工艺在国外得到迅速发展,并已成为生产高辛烷值汽油组分的重要工艺[1,2]。我国目前尚无轻烃异构化装置,但国内许多部门进行了C5/C6异构化催化剂的研究[3～5]。为了尽快发展我国轻烃异构化工艺,研究轻烃异构化催化剂具有重要的意义。以铂为活性组分的烷烃异构化催化剂具有活性高、选择性好、反应条件温和等优点。本文选用铂为金属活性组分、丝光沸石为载体制备了Pt/HM异构化催化剂。研究残钠、金属Pt、助催化剂锆含量,制备方法及反应条件对正戊烷异构化反应性能的影响。1　实　验1 1…     

P(RNCH(2)CH(2))(3)N-catalyzed 1,2-addition reactions of activated allylic synthons.

Activated allylic compounds of the type RCH:CHCH(2)Z (Z = CN, CO(2)Me) react efficiently with aromatic aldehydes in the presence of 20-40 mol % of P(R'NCH(2)CH(2))(3)N at -94 to -63 degrees C. Both R = H and R = Me lead exclusively to alpha-addition products. When R = H and Z = CN, an allylic transposition occurs to afford a Baylis-Hillman product as the only product.     

Cyclohexadienone diazeniumdiolates from nitric oxide addition to phenolates

Sterically hindered phenols react with nitric oxide under basic condititons to give either cyclohexadienone diazeniumdiolates or oximates. Phenols with 2,6-di-tert-butyl and 4-methyl (butylated hydroxy toluene, BHT), 4-ethyl, or 4-methoxy methylene substituents yield the corresponding 2,6-di-tert-butyl-2, 5-cyclohexadienone-4-alkyl-4-diazeniumdiolate salts (4-methyl 1a, 4-ethyl 3a, 4-methoxymethylene 5a). Phenols with 2,6-di-tert-butyl and 4-methylene (2,6-di-tert-butylphenol) substituents yield 4-methoxymethylenediazeniumdiolate (5a) together with 2, 6-di-tert-butyl benzoquinone oximate (6a), while phenols with 2, 6-di-tert-butyl and 4-methylenedimethylamino or hydrogen substituents yield exclusively 2,6-di-tert-butyl benzoquinone oximate (6a). Alkylation of the silver salts of 1a, or treating the O(2)-protonated diazeniumdiolate with diazomethane, both yield mixtures of O(1)- and O(2)-methylated isomers. All the compounds exhibit exothermic thermal decomposition except the quinuclidinium (1e, 3e, 5e) and triethylenediammonium (1f) salts which decompose endothermically. Three of the compounds namely "O(2)-protonated" (Z)-1-[4-(2, 6-di-tert-butyl-4-methyl-cyclohexadienonyl)]diazen-1-ium+ ++-1, 2-diolinic acid (1b), O(2)-methyl (Z)-1-[4-(2, 6-di-tert-butyl-4-methyl-cyclohexadienonyl)]diazen-1-ium+ ++-1,2-diolate (1c), and "O(2)-protonated" (Z)-1-[4-(2, 6-di-tert-butyl-4-methoxymethylenecyclohexadienonyl)]diazen- 1-ium-1, 2-diolinic acid (5b) were characterized by single-crystal X-ray diffraction studies. The diazeniumdiolate framework in all the structures is coplanar with considerable pi-bonding delocalized over the O-N-N-O framework.     

Fast quality assessment of German chamomile (Matricaria chamomilla L.) by headspace solid-phase microextraction: influence of flower development stage

For an adequate quality evaluation of aromatic plants grown under different conditions, a rapid, simple and sensitive method for the analysis of volatile constituents is indispensable. The main objective of the present study was to compare fast screening of German chamomile (Matricaria chamomilla L.) by means of headspace solid-phase microextraction (HS-SPME) with conventional isolation of the essential oil (steam distillation-solvent extraction (SDSE)) for the differentiation of chamomile essential oil constituents. Flowers were harvested at two distinct development stages: stage I, when ligulate flowers start to develop and tubular flowers are still closed, and stage II, when tubular flowers are partially to completely opened. Dried chamomile flowers at two development stages were extracted by means of both SDSE and HS-SPME, followed by GC-MS analysis. Among 30 compounds detected, (E)-beta-farnesene (49%), artemisia ketone (10%) and germacrene D (9%) were the predominant volatile components in the HS-SPME-extract, while alpha-bisabolol oxide A (42%), chamazulene (21%) and (Z)-spiroether (8%) were the main essential oil constituents among the 13 compounds obtained by SDSE. After statistical analysis of the data, both techniques enabled the same conclusion: (E)-beta-farnesene was the only compound which showed significant differences between the two flower development stages. These results suggest that HS-SPME-GC-MS can be used as a sensitive technique for the rapid screening and quality assessment of M. chamomilla.     

Comparative analysis of the oil and supercritical CO(2) extract of Cymbopogon citratus Stapf

Dried and ground leaves of lemon grass (Cymbopogon citratus Stapf.) were used as a matrix for supercritical extraction of essential oil with CO(2). The objective of this study was to analyze the influence of pressure on the supercritical extraction. A series of experiments were carried out, for 360 min, at 50 degrees C and at different pressures: 90, 100, 110 and 120 bar. Extraction conditions were chosen to maximize citral content in the extract oil. The collected extracts were analysed by GC-MS and their composition was compared with that of the essential oil isolated by hydrodistillation and by steam distillation. At higher solvent density the extract aspect changes passing from a characteristic yellow essential oil to yellowish semi-solid mass because of the extraction of high molecular mass compounds. The optimum conditions for citral extraction were 90 bar and 50 degrees C, at these conditions citral represent more than 68% of the essential oil and the extraction yield was 0.65% while the yield obtained from hydrodistillation was 0.43% with a content of citral of 73%.