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1.
In this work, screening of Lauraceae species for their antifungal activity against Collectotrichum tamarilloi was carried out and the ethanol extract derived from the bark of Endlicheria arenosa was found to be the best candidate. From the ethanolic extract of the bark of E. arenosa, the hexane and chloroform fractions were found to be active, from these five fatty acids were identified and two lactones were isolated. The most active fatty acid was the dodecanoic acid with a minimal inhibitory concentration (MIC) of 78.0 μM. The butyrolactone 3R,4R-licunolide A, it has not previously reported, and licunolide B show both the lowest MIC (55.3 μM). This is the first report of compounds of natural origin as growth inhibitors of C. tamarilloi.  相似文献   

2.
The present work describes the fractionation of the crude hexane extract (EBHEX) from Calophyllum brasiliense (Clusiaceae) stem bark. Derivatization of DCM(2-9) fraction with diazomethane afforded the chromanones inophylloidic acid, isobrasiliensic acid, as well as, a mixture containing isobrasiliensic and brasiliensic acids, in the form of their more stable O-methoxy-methyl esters derivatives 1, 2, and 3, respectively. The isolation of 1 from C. brasiliense is described for the first time herein. The use of two-dimensional NMR methods ((1)H-COSY, HMQC, and HMBC) allowed the precise determination of (13)C and (1)H chemical shifts of compounds 1, 2, and 3.  相似文献   

3.
石榴籽中脂肪酸成分分析   总被引:12,自引:0,他引:12  
采用两种方法对石榴籽中的脂肪酸进行了甲酯化,所得脂肪酸甲酯经GC-MS分析.方法一共检测出14种脂肪酸,主成分为油酸、亚油酸、山嵛酸、棕榈酸、硬脂酸和二十碳烯酸;方法二共检测出24种脂肪酸,主成分为棕榈酸、硬脂酸、花生酸、山嵛酸、油酸、亚油酸、二十碳烯酸等.其中的山嵛酸等多种饱和脂肪酸均为首次从石榴籽中鉴定出.  相似文献   

4.
The chemical investigation of the hexane extract of the stem bark of Gordonia ceylanica afforded 3beta-acetoxy-11alpha(2',3'-epoxyferulyloxy)-olean-13(18)-ene as a new natural product and alpha-spinasterol for the first time from Gordonia.  相似文献   

5.
The occurrence of chromanone derivatives has been noticed as a distinctive feature of the genus Calophyllum (Calophyllaceae). Previous studies have demonstrated that the extract of the stem bark of Calophyllum brasiliense and its chromanone-rich fractions show anti-ulcer activity in murine gastric ulcer models. In this work, brasiliensic and isobrasiliensic acids, the two main compounds of the n-hexane extract of the stem bark extract of C. brasiliense, were isolated by flash chromatography using silica gel impregnated with silver nitrate and their structures were elucidated by NMR techniques and mass spectrometry. 13C NMR data is available for the first time for both compounds. Brasiliensic and isobrasiliensic acids showed good in vitro bacteriostatic activity against Helicobacter pylori, and are responsible, at least in part, for the bacteriostatic anti-H. pylori activity of the n-hexane extract of the stem bark of C. brasiliense.  相似文献   

6.
Four new isoflavonoids from the stem bark of Erythrina variegata   总被引:1,自引:0,他引:1  
Bioassay-directed fractionation of the stem bark extract of Erythrina variegata L. has resulted in the isolation of three new isoflavones: 5,4'-dihydroxy-8-(3,3-dimethylallyl)-2'-methoxyisopropylfurano[4,5:6,7]isoflavone (1), 5,7,4'-trihydroxy-6-(3,3-dimethylallyloxiranylmethyl)isoflavone (2), 5,4'-dihydroxy-8-(3,3-dimethylallyl)-2'-hydroxymethyl-2'-methylpyrano[5,6:6,7]isoflavone (3) and a new isoflavanone, 5,4'-dihydroxy-2'-methoxy-8-(3,3-dimethylallyl)-2',2'-dimethylpyrano[5,6:6,7]isoflavanone (4) together with seven known compounds, euchrenone b10 (5), isoerysenegalensein E (6), wighteone (7), laburnetin (8), lupiwighteone (9), erythrodiol (10), and oleanolic acid (11). The structures were determined on the basis of spectroscopic analyses and chemical evidence. The effect of these compounds on the proliferation of rat osteogenic sarcoma (UMR106) is also reported.  相似文献   

7.
Saponifiable and unsaponifiable fractions of Ficus microcarpa leaves hexane extract have been phytochemically studied and evaluated for its hypolipidaemic and antioxidant effects in hypercholesterolemic rats. The effect of the extract on the lipid profile was assessed by measuring the levels of total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides, phospho and total lipids. Lipid peroxides, glutathione and superoxide dismutase were measured as antioxidants. The work was extended to evaluate liver function indices as well as the histopathological picture of the liver after treatment. Treatment with leaves extract (500 mg kg?1 body weight) 5 times/week for 9 weeks at the same time of cholesterol administration (30 mg/0.3 mL 0.7% tween/animal) recorded an improvement of lipid profile, antioxidants, liver function enzymes and the liver histopathological picture. The lipoidal matters of the unsaponifiable fraction of the hexane extract by GC/MS led to the identification of 22 compounds, while saponifiable fraction by (MS/MS) technique led to identification of 13 unsaturated and saturated fatty acid methyl ester derivatives. It can be concluded that the hexane extract of F. microcarpa L has been proved to have hypolipidaemic and antioxidant effects in hypercholesterolemic rats through its role in counteracting LDL oxidation, enhancement of HDL synthesis and inhibition of lipid peroxidation.  相似文献   

8.
Ten phenolic compounds, isofraxidin (1), (+)-syringaresinol-di-O-beta-D-glucoside (2), syringin (3), chlorogenic acid (4), isofraxidin-7-O-beta-D-glucoside (5), 2,6-dimethoxy-p-benzoquinone (6), (+)-pinoresinol-O-beta-D-glucoside (7), (7), (+)-syringaresinol-O-beta-D-glucoside (8), (+)-pinoresinol-di-O-beta-D-glucoside (9) and (+)-medioresinol-di-O-beta-D-glucoside (10), were isolated from the stem bark of Acanthopanax senticosus Harms and identified, respectively. The aqueous extract of the stem bark exhibited a prolonging effect on the exercise time to exhaustion in chronic swimming stressed rats. The effect on the exercise time in the chronic swimming stressed rats was respectively tested for compounds 2 and 4, which are major constituents of the stem bark. As a result, it was indicated that compound 2 is the compound responsible for part of the pharmacological effect which the aqueous extract of the stem bark showed.  相似文献   

9.
Grasses (family Poaceae) are economically important plants; they are used as crops and animal foods. Stipagrostis plumosa (L.) Munro ex T. Anderson is a member of this family and subjected to chemical and biological studies. The chromatographic techniques,  LC–ESI–MS and GC/MS were used for identification of polar and non-polar compounds in its extract. Ten compounds, including one new flavone glycoside; tricin 7-O-galactoside, three known flavones, three C-glycosyl flavones and three phenolic acids, were isolated from S. plumosa for the first time except tricin. Their structures were elucidated on the basis of extensive spectroscopic interpretation. In addition to the isolated compounds, eleven compounds were tentatively identified using LC–ESI–MS, five of them were detected for the first time from this species. 29 non polar compounds were identified using GC–MS analysis, representing 83.13% of S. plumosa diethyl ether extract. In addition to the DPPH activity evaluation, the crude extract and the isolated compounds were investigated against five human carcinoma cell lines; A549, HCT-116, HepG2, MCF-7 and PC3 at a concentration of 100 μg/ml. From the isolated compounds tricin and luteolin 6,8-di-C-glucoside could be considered as natural-free radical scavenging agents.  相似文献   

10.
Essential oil and neutral lipids from the cone berries ofJuniperus seravschanica Kom. have been characterized for the first time. Fifty six components comprising 96.5% of the essential oil were identified; a-pinene (29.0%), -myrcene (17.9%), germacrene B (5.9%), and cedrol (3.1%) dominated; 5 classes of neutral lipids were found with a high content of the fatty acids 22:2 (10,13), 22:1 (13), and 18:2 (9,12).Published in Khimiya Prirodnykh Soedinenii, No. 4, 445–448, July–August, 1999.  相似文献   

11.
Candidate kairomones of ornithophilic mosquito species are reported from GC/MS analysis of compounds from the skin on the back, the feet, and feathers from the back of White Leghorn chickens (Gallus gallus domesticus). Hexane and ether extracts of chicken feathers differ significantly in attractiveness of Culex spp. mosquitoes. The active (hexane) extracts contained an abundance of alcohols, ketones, and diones. The inactive (ether) extracts contained aldehydes, which also were in the hexane extracts. Analysis of hexane extracts from chicken feet, skin, and feathers demonstrated the qualitative similarity in the compounds collected with subtle differences observed in the quantitative amounts of these compounds. Aldehydes and carboxylic acids were detected in a concentrated ether extract of feathers in quantitatively similar ratios within each compound class for the corresponding series of C(6)-C(9 )aldehydes and acids.  相似文献   

12.
Capillary supercritical fluid chromatography (SFC) with carbon dioxide as the mobile phase has been used to separate a mixture of limonoid standards. Chromatographic conditions were optimized to enable analysis of plant extracts. The seed of Aphanamixis polystacha (Meliaceae) and the stem bark of Harpephyllum caffrum (Anacardiaceae) were extracted with hexane and the extracts were analyzed by SFC to demonstrate the potential of the technique as a screening tool. SFC analysis indicated the presence of limonoids in the hexane extract of the bark of Entandrophragma delevoyii (Meliaceae). One limonoid and two protolimonoids isolated from the extract were separated by SFC.  相似文献   

13.
Considering medicinal plants as an inexhaustible source of active ingredients that may be easily isolated using simple and inexpensive techniques, phytotherapy is becoming increasingly popular. Various experimental approaches and analytical methods have been used to demonstrate that the genus Calendula (Asteraceae) has a particular richness in active ingredients, especially phenolic compounds, which justifies the growing interest in scientific studies on this genus’ species. From a chemical and biological viewpoint, Calendula aegyptiaca is a little-studied plant. For the first time, high-performance liquid chromatography combined with negative electrospray ionization mass spectrometry (HPLC-HESI-MS) was used to analyze methanolic extracts of Calendula aegyptiaca (C. aegyptiaca) fruits. Thirty-five molecules were identified. Flavonoids (47.87%), phenolic acids (5.18%), and saponins (6.47%) formed the majority of these chemicals. Rutin, caffeic acid hexoside, and Soyasaponin βg’ were the most abundant molecules in the fruit methanolic extract, accounting for 17.49% of total flavonoids, 2.32 % of total phenolic acids, and 0.95% of total saponins, respectively. The antioxidant activity of the fruit extracts of C. aegyptiaca was investigated using FRAP, TAC, and DPPH as well as flavonoids and total phenols content. Because the phenolic components were more extractable using polar solvents, the antioxidant activity of the methanolic extract was found to be higher than that of the dichloromethane and hexane extracts. The IC50 value for DPPH of methanolic extract was found to be 0.041 mg·mL−1. Our findings showed that C. aegyptiaca is an important source of physiologically active compounds.  相似文献   

14.
Chemistry of Natural Compounds - A new seco-abietanoid, 12-hydroxy-6,7-seco-abieta-8,11,13-triene-6,7-dioic acid (1), was isolated from the methanol extract of the bark of Cryptomeria japonica. The...  相似文献   

15.
Two crystalline compounds from the bark of Taiwania cryptomerioides Hayata were isolated. One of them was identified as 6,7-dehydroroyleanone and the other was shown to be a new derivative of royleanone having a structure of 6β-acetoxy-7α-hydroxyroyleanone.  相似文献   

16.
The aims of the present study were to determine the antibacterial activity of bark extract of Cryptomeria japonica D. Don and to isolate potential antibacterial constituents. The results showed that the ethanolic extract of C. japonica bark possessed a good antibacterial activity. Nine compounds including seven diterpenoids (ferruginol (I), isopimaric acid (II), iguestol (III), isopimarol (IV), phyllocladan-16alpha-ol (V), sandaracopimarinol (VI) and sugiol (VII)) and two steroids (beta-sitosterol (VIII) and beta-sitostenone (IX)) were isolated from active subfractions; beta-sitostenone was isolated for the first time from this plant. Among these compounds, ferruginol possessed the strongest antibacterial activity and had MIC values ranging from 6.3 to 12.5 microg mL(-1) against all bacteria tested. Isopimaric acid was also an antibacterial natural product. Cryptomeria japonica bark extract and its diterpenoids, ferruginol and isopimaric acid, have the ability to inhibit the bacterial growth and can be used as the source for natural bactericides.  相似文献   

17.
In this paper, macroporous resin column chromatography and counter‐current chromatography (CCC) were applied for large‐scale preparative separation of three flavonoids from the flower of Daphne genkwa, a famous Chinese medicinal herb. Nine kinds of resins were investigated by adsorption and desorption tests and D101 macroporous resin was selected for the first cleaning‐up, in which 40% aqueous ethanol was used to remove the undesired constituents and 90% aqueous ethanol was used to elute the targets. The crude extract after the first step was directly subjected to the preparative CCC purification using the solvent system composed of n‐hexane–ethyl acetate–methanol–water (4:5:4:5, v/v). The compounds apigemin (823 mg), 3‐hydroxyl‐genkwanin (842 mg) and genkwanin (998 mg) with the purities of 98.79, 97.71 and 93.53%, respectively, determined by HPLC were produced from 3‐g crude extract only in one CCC run. Their chemical structures were identified by MS, UV and the standards.  相似文献   

18.
The chemical composition of the volatile extract (yield ≈ 0.13%, v/w) from the bark of Quercus leucotrichophora (Fagaceae) was analysed for the first time by GC-MS. Twenty-three constituents, amounting to 93.0% of the total detected contents of the volatile extract, were identified. The volatile extract contained approximately 86.36% monoterpenoids, 6.53% sesquiterpenoids and 0.11% aliphatic aldehydes. 1,8-Cineol (40.359%) followed by γ-terpinene (16.369%) were the major monoterpene constituents of the volatile extract. The residue of volatile extract (0.00025-250 μg mL(-1)) exhibited a potent antimicrobial activity against Streptococcus pyogenes ATCC 19615. This study concludes that residues of the volatile extract of Q. leucotrichophora could serve as an important bioresource for the extraction and isolation of monoterpenoids exhibiting antimicrobial activity, and thus has good potential for use in the pharmaceutical industry.  相似文献   

19.
气相色谱-质谱法测定蒜头果油中的脂肪酸   总被引:31,自引:1,他引:31  
周永红  李伟光  易封萍  刘雄民 《色谱》2001,19(2):147-148
 对云南产蒜头果油用硫酸 甲醇法酯化 ,以气相色谱 质谱 计算机联用仪进行了分析。共分离出 17种成分 ,鉴定了其中的 7种成分 ,分别为棕榈酸 (质量分数 (下同 ) 1.5 0 % )、油酸 (2 1.5 4% )、二十碳烯 11 酸 (7.0 4% )、芥酸(18.2 9% )、二十二烷酸 (1.33% )、二十四碳烯 15 酸 (4 0 .92 % )、二十四烷酸 (2 .14% ) ,占总质量的 92 .76 % ;未被鉴定的成分占总质量的 7.2 4%。  相似文献   

20.
The anti-allergic active fractionation of hexane extracts of the leaves and stems of Anchietia salutaris var. martiana (family Violaceae) was performed by monitoring their activities with an in vitro bioassay system measuring the inhibitory effects on induced histamine release from guinea pig lung cells. Three known pentacyclic triterpenes (friedelin, alpha-amyrin, beta-amyrin) were isolated, but these compounds were inactive. Aliphatic hydrocarbons and methyl esters of fatty acids (palmitic, oleic, linoleic, linolenic acids) were detected in active fractions. All compounds isolated were detected for the first time in this medicinal plant.  相似文献   

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