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1.
The structural modification of ursolic acid by an endophytic fungus Pestalotiopsis microspora, isolated from medicinal plant Huperzia serrata was reported for the first time. The structure diversity was very important for the SAR study of ursolic acid and its derivatives. Incubation of ursolic acid 1 with P. microspora afforded four metabolites: 3-oxo-15α, 30-dihydroxy-urs-12-en-28-oic acid (2), 3β, 15α-dihydroxy-urs-12-en-28-oic acid (3), 3β, 15α, 30- trihydroxy-urs-12-en-28-oic acid (4) and 3,4-seco-ursan-4,30-dihydroxy-12-en-3,28-dioic acid (5). All products were new compounds and their structures elucidation was mainly based on the spectroscopic data.  相似文献   

2.
Lu W  Zou J  Chen J  Zhu Y  Ya Q  Zhao W 《Fitoterapia》2007,78(7-8):614-616
Two new compounds, 4-ethoxycarbonyloxy-3,3',4'-trimethoxy-ellagic acid (1) and 4-E-propenyl-phenol-1-O-beta-D-rutinoside (2), together with four known compounds, 3,3',4'-trimethoxy-ellagic acid (3), 3,3'-dimethoxy-ellagic acid (4), 3,3',4'-trimethoxy-ellagic acid-4-O-beta-D-glucopyranoside (5) and 3'-methoxy-ellagic acid-4-O-alpha-L-rhamnopyranoside (6), were isolated from the whole plant of Cleidion brevipetiolatum. Their structures were elucidated from spectral evidences.  相似文献   

3.
A new stearoyl glucoside of ursolic acid, urs-12-en-3β-ol-28-oic acid 3β-d-glucopyranosyl-4′-octadecanoate and other compounds were isolated from the leaves of Lantana camara L. The structure of this new glycoside was elucidated and established by standard spectroscopic methods. In streptozotocin-induced diabetic rats it showed significant reduction in blood glucose level.  相似文献   

4.
Constituents from Lonicera japonica   总被引:4,自引:0,他引:4  
Peng LY  Mei SX  Jiang B  Zhou H  Sun HD 《Fitoterapia》2000,71(6):1356-715
Five caffeoylquinic acids and esters (1-5), including a new compound, 3,5-dicaffeoylquinic acid butyl ester (5), were isolated from the flowers and buds of Lonicera japonica and their structures were determined by NMR spectral analysis.  相似文献   

5.
Two new clerodane diterpenoids 2β-methoxy-cleroda-3,13-dien-18-carboxy-15,16-olide (1) and 15ξ-methoxy-cleroda-3,12-dien-18-carboxy-15,16-olide (2) and one new nitrogen-containing clerodane diterpenoid 15-oxo-echinophyllin A (3), along with six known compounds, namely, echinophyllin A, (−)-patagonic acid, tyrosol, oplopanone, 4-hydroxy-4-methyl-2-[(1R)-1-(1-methylethyl)-4-oxopentyl]-2-cyclohexen-1-one and 1β,6α-dihydroxy-eudesman-4(15)-ene were isolated from the leaves of Casearia sylvestris. Their structures were determined by extensive NMR techniques.  相似文献   

6.
Antihyperglycemic activity of the aqueous extract of Urtica dioica   总被引:5,自引:0,他引:5  
When administered 30 min before glucose loading, the aqueous extract of Urtica dioica (nettle) (250 mg/kg) showed a strong glucose lowering effect. The decrease of glycemia has reached to 33+/-3.4% of the control value 1 h after glucose loading. This effect was persistent during 3 h. In contrast, nettle did not show hypoglycemic effect in alloxan-induced diabetic rats. The amount of glucose absorbed in a segment jejunum in situ was 8.05+/-0.68 mg in presence of nettle extract vs. 11.11+/-0.75 mg in control rats during 2 h (P<0.05). The results indicate that nettle has a significant antihyperglycemic effect in OGTT model. This effect may be caused in part by the reduction of intestinal glucose absorption. LD(50) is 3.5 g/kg (i.p.).  相似文献   

7.
陈建白 《热带农业科技》2004,27(2):16-20,25
概述了ω-3膳食对人体健康的研究动态,介绍了橡胶种子、油梨、澳洲坚果等富含ω-3脂肪酸与油酸的热带作物油料,是人们摄取ω-3脂肪酸及大量油酸的新资源。  相似文献   

8.
Ti H  Wu P  Lin L  Wei X 《Fitoterapia》2011,82(4):662-665
The first stilbene possessing a γ-aminobutyric acid lactam function, artocarpene (1), and a new flavanone, 2-hydroxynaringenin 4′-O-β-d-glucopyranoside (2), were isolated from the stems of Artocarpus nitidus subsp. lingnanensis along with four known compounds, 2-hydroxynaringenin (3), oxyresveratrol (4), 3,4′,5-trihydroxy-3′-prenylstilbene (5) and norartocarpetin (6). Their structures were elucidated on the basis of spectroscopic data. Compounds 1 exhibited weak antioxidant activity and 2 displayed weak cytotoxicity against human lung cancer A549 cell line.  相似文献   

9.
A new arylnaphthalene lignan, named furfuracin (1), was isolated from the leaves of Knema furfuracea (Myristicaceae), whereas 7 known compounds including (+)-trans-1,2-dihydrodehydroguaiaretic acid, fragransin A2, biochanin A, gingkolic acid, anarcardic acid, 2-hydroxy-6-(12-phenyldodecyl)-benzoic acid and 2-hydroxy-6-(12-phenyldodecen-8′Z-yl)-benzoic acid were obtained from its stems. The structure of the new lignan was established by analysis of spectroscopic data (UV, IR, MS and NMR).  相似文献   

10.
Wang R  Wei Wang  Wang L  Liu R  Yi Ding  Du L 《Fitoterapia》2006,77(7-8):534-537
A new polyphenol compound named pomegranatate (1), together with, ellagic acid, 3,3',4'-tri-O-methylellagic acid, ethyl brevifolincarboxylate, urolic and maslinic acids, and daucosterol were isolated from the ethanolic extract of the flowers of Punica granatum. The structure of compound 1 was determined by spectroscopic analysis. Maslinic acid exhibited antioxidant activity, evaluated by measurement of LDL susceptibility to oxidation.  相似文献   

11.
The total amounts of endogenous indole-3-acetic acid (IAA), cytokinins, and abscisic acid (ABA) were quantified by gas chromatography-selected ion monitoring-mass spectrometry (GC-SIM-MS) in cambial regions of the main stems ofLarix kaempferi during the spring season. During the sampling period, cambium in the dormant state entered the active meristematic state. The total amount of IAA did not change at the onset of cambial reactivation but increased when the active division of cambial cells became apparent. Four cytokinins —trans- andcis-ribosylzeatin (RZ),N 6-isopentenyladenine (iP),N 6-isopentenyladenosine (iPA) — were quantified, but no zeatin (Z) was detected. The total amount of the four cytokinins together and the total amount of isopentenyl-type cytokinins (iP and iPA) varied during the sampling period but did not appear to be specifically associated with cambial activity. The total amounts oftrans- andcis-RZ remained relatively constant during the sampling period, as did the total amount of ABA. The results suggest that there is little correlation between total amounts of endogenous plant hormones in the cambial region and reactivation of the cambium during the spring.  相似文献   

12.
Cuttage propagation of Aesculus indica was tested by treatments with different concentrations of indole-3-acetic acid (IAA) @ 2000, 4000 (ppm), indolebutyric acid (IBA) @ 2000, 4000 (ppm) and naphthlcetic acid (NAA) @ 2000, 4000 (ppm) in dry formulation in the Forest Nursery, Faculty of Forestry, SKUAST-K, Shalimar. The cuttings treated with IBA @ 4000 ppm and IBA @ 2000 ppm had a sprouting rate of 75% and 50%, respectively, which was significantly higher than that of control and other treatments. The highest rooting rate (50%) was recorded in the cuttings with the application of IBA @ 4000 ppm. The cuttings treated with IBA @ 2000 ppm had 25% rooting rate. All other treatments along with control (talc powder) failed to induce rooting. It was concluded that IBA @ 4000 ppm was a better-applied concentration for vegetative propagation of A. indica under Kashmir conditions. Biography: Mumtaz Majeed (1980– ), male, post graduate in Faculty of Forestry, Sher-e-Kashmir University of Agricultural Science & Technology, Shalimar, Srinagar - 191 121, J&K, India.  相似文献   

13.
Leandra lacunosa, popularly known as "erva-do-jabuti", is used in Brazilian folkloric medicine for the treatment of diabetes mellitus. Based on this traditional indication, the aim of this work was to evaluate the hypoglycemic activity of the hydroalcoholic extract of L. lacunosa aerial parts (LLH) in normal and alloxan-induced diabetic rats. Chromatographic fractionation of LLH was also carried out by several techniques, affording isolation of the following major compounds: ursolic acid (1), kaempferol (2), luteolin (3), and quercetin (4). The oral administration of LLH (500 mg/kg) in normal rats caused a significant reduction of 24.7% (P<0.05) in the blood glucose levels after 2 h of treatment, while the administration of chlorpropamide (20 mg/kg, p.o.) led to a reduction of 40.2% (P<0.01). After oral administration of glucose (10 g/kg, p.o.), LLH (500 mg/kg, p.o.) significantly inhibited the increase in blood glucose levels compared with the negative control group. The oral treatment with LLH (500 mg/kg) in alloxan-induced diabetic rats significantly reduced the blood glucose levels in 47.8% after 4 h of treatment, while chlorpropamide resulted in a significant reduction of 71.7% in the 4th hour. Our results showed that LLH, displays hypoglycemic activity, which may be related to the effect of the major compounds identified in the crude extract. This study seems to provide biological evidence for the folkloric use of L. lacunosa in the treatment of diabetes mellitus.  相似文献   

14.
Baker JR  Kim JS  Park SY 《Fitoterapia》2008,79(5):345-350
Phellinus linteus is a mushroom which has been prized in Korea for its medicinal properties since ancient times. A glycan preparation from this source has shown promise in experimental anti-tumour and metastasis studies, but the glycan has not been well characterized. In the present work, the glycan fraction of a hot water extract from P. linteus (Keumsa Sangwhang Mushroom, Korea) has been isolated following ammonium sulfate precipitation, dialysis/concentration and anion exchange chromatographic steps. Analyses for monosaccharide composition showed glucose and mannose to be the major constituents. Digestion of the glycan fraction with specific glycosidases and by linkage analysis allowed us to propose a core beta(1-3) linked glucan heavily substituted via (1-6) links with beta(1-3) linked mannose chains. Significant levels of galactose and xylose, present in the glycan fraction, may be associated with this glucomannan or not. These findings are consistent with the view that a core beta(1-3)-linked glucan chain with beta(1-6) branch points is a common feature of mushroom glycans possessing anti-tumour activity.  相似文献   

15.
Fractions of methanol and ethanol extracts from the heartwood of white cypress pine (Callitris glaucophylla Thompson et Johnson) were investigated for their repellent activity against subterranean termite Coptotermes formosanus Shiraki worker using a two-choice semicircular filter paper test at 0.5% (w/w) concentration. Fraction CY-E2 composed of (−)-citronellic acid, guaiol, α-, β-, and γ-eudesmol isomers as well as an unknown compound, showed the highest statistically significant repellency (97.8% ± 2.2 SEM) of all fractions tested. Bioactivity-guided fractionations using high-performance liquid chromatography led to the isolation of two, oxygenated eudesmane-type sesquiterpenes with α-methylene moieties, both termite-repellent compounds. These compounds were subsequently identified as ilicic acid methyl ester (IAME) and costic acid by means of spectroscopic analyses, electron impact mass spectrometry, and nuclear magnetic resonance spectroscopy. We report the isolation of both IAME and costic acid from C. glaucophylla heartwood for the first time. Part of this paper was presented at the 47th Symposium on the Chemistry of Terpenes, Essential Oils, and Aromatics, Tokyo, November 2003  相似文献   

16.
[目的]确定引起天女木兰褐化现象的酚酸种类,筛选出最佳抗褐化剂及使用最适浓度。[方法]在B5培养基中分别添加各种抗褐化剂,芽外植体培养30 d后计算出褐化率,对褐化率结果进行统计分析,并比较三种抗褐化剂的抗褐化效果;另外,在组培过程中定期取样,利用HPLC测定芽外植体中咖啡酸、绿原酸和对香豆酸含量变化。[结果]表明:天女木兰芽外植体褐化过程中咖啡酸和绿原酸含量下降幅度较大,而对香豆酸含量下降幅度较小,说明咖啡酸和绿原酸容易被氧化,而对香豆酸较为稳定;三种抗褐化剂控制褐化现象发生的最佳效果排序为VCPVPCA;尽管PVP控制酚酸氧化效果不如CA,但是预防褐化效果确强于CA,其原因是由于二者抗褐化机理不同所致;VC使用的最适浓度为500 mg·L~(-1),如果超过此浓度会导致外植体褐化率增加;PVP最适浓度为1 000~1 500 mg·L~(-1),CA最适浓度为300 mg·L~(-1)。[结论]天女木兰芽外植体褐化底物是咖啡酸和绿原酸,而与对香豆酸无关;VC、PVP和CA三种抗褐化剂抗褐化机理各不相同,综合比较VC抗褐化效果最好,其次是PVP,CA排在最后。  相似文献   

17.
Two new betaine-type amphoteric surfactants — betaineN,N'-dihydroxyethyl-N-ethyl fatty acid ester and ammoniumN-(fatty acid ester) ethyl-N,N-bis (2-hydroxyethyl)-3-(2-hydroxypropyl) sulfonate — were synthesized using tall oil fatty acids as the raw materials. Processing conditions suitable for synthesizing the intermediates and final products were probed. In addition, the chemical structures of the intermediates and the final products were identified by infrared spectroscopy, hydrogen nuclear magnetic resonance spectroscopy, and elemental analysis.  相似文献   

18.
A new kaurane diterpene dimer, 15-oxozoapatlin-13alpha-yl-10'alpha,16'alpha-dihydroxy-9'alpha-methyl-20'-nor-kauran-19'-oic acid gamma-lactone-17'-oate (1), together with the known 13-hydroxy-15-oxozoapatlin (2), 10alpha,13alpha,16alpha,17-tetrahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid gamma-lactone (3), 2alpha,10alpha,13alpha,16alpha,17-pentahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid (19,10)-lactone (4), 3alpha,10alpha,13alpha,16alpha,17-pentahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid gamma-lactone (5), and 1beta,16alpha,17-trihydroxy-ent-kaurane (6) were isolated from the leaves of Parinari campestris and identified on the basis of detailed spectral analysis, including 2D NMR spectrometry and ESI-MS.  相似文献   

19.
Wu SH  Chen YW  Yang LY  Li SL  Li ZY 《Fitoterapia》2008,79(6):474-475
A new ellagic acid glycoside, 4'-O-methylellagic acid 4-O-beta-D-glucopyranoside (1), was isolated from the root cortex of Paeonia delavayi. The structure was elucidated on the basis of spectroscopic methods.  相似文献   

20.
Phytochemical investigation on Clusia burlemarxii (Clusiaceae) led to isolation and identification of nine compounds. Were isolated from leaves 3-O-α-L- rhamnopyranosylquercetin, 3-O-α-L-rhamnopyranosylkaempferol, 4-hydroxy-5,5-dimethyldihydrofuran-2-one, 2Z-δ-tocotrienoloic acid and friedelin and were isolated from trunk betulinic acid, protocatechuic acid, lyoniresinol, and a new biphenyl 2,2-dimethyl-3,5-dihydroxy-7-(4-hydroxyphenyl)chromane. The structures were determined by 1H, 13C-NMR, DEPT, HMBC, HMQC, HRESIMS. The Minimal Inhibitory Concentration against Streptococcus mutans, Staphylococcus aureus, Bacillus subtilis, Micrococcus luteus, Escherichia coli, Salmonella choleraesuis, Pseudomonas aeruginosa, Aspergillus niger and Cladosporium cladosporioides was also determined. Extracts and compounds showed significant activity against tested Gram-positive bacteria, none activity against tested Gram-negative bacteria and fungi.  相似文献   

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