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1.
Blood coagulation consists of a series of zymogens that can be converted by limited proteolysis to active enzymes leading to the generation of thrombin. Fresh plasma and human thrombin was incubated with extracts from berries of Aronia melanocarpa or seeds of Vitis vinifera (0.5; 5; 50 μg/ml). The in vitro experiments showed that both extracts prolonged clotting time and decreased the maximal velocity of fibrin polymerization in human plasma. Moreover thrombin incubation with both extracts results in the inhibition of amidolytic activity of this enzyme. It gives hopes for development of diet supplements, which may be preventing thrombosis in pathological states.  相似文献   

2.
Prasad D 《Fitoterapia》2000,71(3):245-253
Two A-type proanthocyanidins, ent-epiafzelechin-(4alpha-->8, 2alpha-->O-->7)-(-)-epicatechin and its isomer, ent-epiafzelechin-(4alpha-->8', 2alpha-->O-->7')-catechin, together with other known compounds, have been isolated from the roots of Prunus armeniaca. The concerted use of one- and two-dimensional NMR methods (1H-(1)H COSY, HMQC, HMBC and NOESY) allowed the identification of these compounds.  相似文献   

3.
Flavanol values, molecular weight distributions, polyphenolic patterns, and tyrosinase inhibitions of proanthocyanidins (PACs) from karamatsu (Larix sp.) bark, acacia Morishima (Acacia mearnsii) bark, and commercial quebracho (Schinopsis lorentzii) extracts were examined to investigate the relation between the structures of PACs from woody plants and tyrosinase inhibitory activities. Aqueous acetone (70%) extracts of acacia showed high flavanol contents and strong tyrosinase inhibition. On the other hand, the quebracho extracts inhibited tyrosinase activity slightly despite its high flavanol content. Phenyl nucleus analysis by the nucleus exchange reaction provided information that karamatsu, quebracho, and acacia extracts consist of procyanidin, profisetinidin, and prorobinetinidin, respectively. The relation between the phenolic hydroxylation pattern and tyrosinase inhibition suggested that the PACs with a 5,7-dihydroxyphenyl structure in the A-ring and a 3,4,5-trihydroxyphenyl structure in the B-ring have potent tyrosinase inhibitory activity.Part of this paper was presented at the 49th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1999  相似文献   

4.
We investigated the effect of stratification on the proteinase activity involved in mobilization of the major soluble approximately 45 kDa storage protein during germination of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seeds. Complete hydrolysis of the approximately 45 kDa protein was observed approximately 7 days after exposure of stratified seeds to germination conditions. Coincident with the onset of mobilization, proteinase activity was detected primarily in microsomal extracts from stratified seeds. Microsomal-associated proteinase activity was most active at pH 8.0 and had a molecular mass > 175 kDa as determined by gelatin SDS-PAGE gels. In vitro digestion of soluble protein extracts indicated that, following stratification, there was a significant increase in proteinase activity and hydrolysis of the approximately 45 kDa storage protein. Whether this increase was a result of activation of preexisting proteinase(s) or de novo synthesis remains unknown. In vitro digestion of soluble protein extracts in the presence of various proteinase inhibitors showed that digestion of the approximately 45 kDa storage protein is mediated primarily by a metalloproteinase and to a lesser degree by a serine proteinase. The accumulation of approximately 25 kDa protein products following in vitro digestion suggests that mobilization of the approximately 45 kDa soluble storage protein is mediated by a multi-step process involving the action of different classes of proteinases.  相似文献   

5.
Akgul YY  Anil H 《Fitoterapia》2003,74(7-8):743-745
A new benzofuran was isolated from seeds of Styrax officinalis and has been identified as 5-[3"-(2-methylbutanoyloxy) propyl]-7-methoxy-2-(3',4'-dimethoxyphenyl) benzofuran (1) by means of spectroscopic analysis.  相似文献   

6.
响应面法优化野生毛葡萄中原花青素醇提工艺的试验   总被引:3,自引:0,他引:3  
依据响应面试验设计法,选取乙醇浓度(A)、料液比(B)、反应温度(C)为考察因素,对野生毛葡萄籽中原花青素醇提工艺进行优化试验。经对各因素的显著性和交互作用的分析,得出野生毛葡萄籽中原花青素醇提的最佳工艺条件为:乙醇浓度为64%、料液比为1∶7、提取温度为35℃。建立的原花青素醇提数学模型为:Y=0.61-0.058A+0.029B-0.12C+0.025AC-0.013BC-0.091A2-0.095B2-0.17C2,原花青素得率的预测值为86.95 mg.g-1、验证值为85.54 mg.g-1。证明此模型是合理可靠的,可用于实际预测。  相似文献   

7.
An investigation of the triterpenoid fraction of zucchini seeds afforded two novel multiflorane p-aminobenzoates, identified as 7-epi zucchini factor A and debenzoyl zucchini factor B. Multiflorane p-aminobenzoates could not be detected in zucchini sprouts, which contained bryonolic acid as the only multiflorane constituent. No compound of this type could be obtained from adult plant parts (roots, stems, leaves).  相似文献   

8.
Psoralidin, bakuchicin, psoralin and angelicin, isolated from the seeds of Psoralea corylifolia, showed significant antibacterial activities against a number of Gram (+) and Gram (-) bacteria.  相似文献   

9.
The isolation and NMR spectra of 2-exo,3-endo-camphanediol (1) and 2-pinene-4,10-diol (2) from the seeds of Heracleum candolleanum are reported.  相似文献   

10.
《Fitoterapia》1999,70(4):446-448
The isolation and 13C-NMR spectra of Δ14-vincanol, O-methyl-16-epi-Δ14-vincanol, Δ14-vincamone from the seeds of Voacanga africana are reported.  相似文献   

11.
Activity-guided fractionation of seeds of Solanum indicum for anti-HBV activity led to the isolation of two novel coumarinolignoid alkaloids (indicumines A–B, 12) and two new coumarinolignoids (indicumines C–D, 34), together with four known coumarins (58). Their structures were established on the basis of spectroscopic data. The two novel coumarinolignoid alkaloids shows anti-HBV activities through specifically inhibiting the secretion of HBsAg in HepG2.2.15.  相似文献   

12.
The influence of proanthocyanidin (PA) structures contained in bark on color development in the vanillin-hydrochloric acid (V-HCl) method used widely as a quantitative method for measuring PA were examined. The maximal absorption wavelength was different in terms of the bark from which the PA was obtained. Phenyl nucleus (resorcinol, phloroglucinol) constituting the A-ring of PA reacts with vanillin to produce the color. The maximal absorption wavelengths of the solutions from synthesized procyanidin and profisetinidin were 500 and 540 nm, respectively, indicating that the color tone differs in the V-HCl method based on the hydroxylation patterns of the A-ring. The colored solution of (+)-catechin with vanillin was dialyzed, and the resulting product (C-VC) was analyzed by gel permeation chromatography and 1H nuclear magnetic resonance. It was found that C-VC was a polymer complex consisting of 9mol (+)-catechin moieties and 10mol vanillin moieties. It was presumed that the cationized vanillin molecules that do not combine with (+)-catechin play an important role on color development in the presence of C-VC.This study was presented at the 44th and 45th Annual Meetings of The Japan Wood Research Society, Nara and Tokyo, April 1994 and April 1995  相似文献   

13.
Yadava RN  Rathore K 《Fitoterapia》2001,72(3):310-312
A new cardenolide, cannogenol 3-O-beta-D-galactopyranosyl-(1-->4)-O-alpha-L-rhamnopyranoside (1), was isolated form the seeds of Teminalia bellerica.  相似文献   

14.
The diterpenoids 16alpha-hydroxy-cleroda-3,13 (14)-Z-diene-15,16-olide (1) and 16-oxo-cleroda-3, 13(14)-E-diene-15-oic acid (2), isolated from the hexane extract of the seeds of Polyalthia longifolia, demonstrated significant antibacterial and antifungal activities.  相似文献   

15.
E Attard  H Attard 《Fitoterapia》2008,79(3):226-228
The antitrypsin activity of extracts obtained from two different seed types of Ecballium elaterium, was tested in vitro. The presence of trypsin inhibitors in three chromatographed samples for each extract, showed a strong and specific antitrypsin activity.  相似文献   

16.
Low molecular weight globulins, which are abundant proteins in the Pinus pinaster Ait. megagametophyte, were purified and characterized. They showed a dimeric structure formed of one large and one small subunit linked by disulfide bridges. They were characterized by a high Arg and Glx content and by a relatively high Cys content. A comparison of their characteristics with those of angiosperm 2S proteins suggests that there is homology between them.  相似文献   

17.
Tang W  Xu H  Zeng D  Yu L 《Fitoterapia》2012,83(3):513-517
Three new phenolic constituents, itolide A (1), itolide B (2), itoside P (3), and 1D-3-deoxy-3-hydroxymethyl-myo-inositol (4), which is described herein for the first time as a natural product, were isolated along with four other known compounds (5 to 8) from the methanol extract of the seeds of Itoa orientalis Hemsl by the activity-guided fractionation. Their structures were determined by spectroscopic means. Compounds 1 to 8 exhibited antifungal activities against Sclerotium rolfsii with IC50 values ranging from 60.12 to 240.00 μM and against Rhizoctonia solani with IC50 values ranging from 45.34 to 233.14 μM, respectively, and compounds 1, 2, 5 exhibited cytotoxic activity against Tn5B1-4 insect cell line with EC50 values of 203.68, 93.41 and 40.37 μM, respectively.  相似文献   

18.
A new pyrrole alkaloid from seeds of Castanea sativa   总被引:1,自引:0,他引:1  
A new pyrrole alkaloid, methyl-(5-formyl-1H-pyrrole-2-yl)-4-hydroxybutyrate (1), was isolated from sweet chestnut seeds and its structure elucidated on the basis of data from NMR spectroscopy and by comparison with synthetic analogues.  相似文献   

19.
《Fitoterapia》1999,70(3):284-286
A new cardenolide, 3β,14β-dihydroxy-5β-card-20(22)-enolide 3 -O-β-d-glucopyranosyl-(1(4)-α-l-rhamnopyranoside (1) has been isolated from the seeds of Prosopis spicigera.  相似文献   

20.
沙棘籽原花青素提取单因素实验研究   总被引:1,自引:0,他引:1  
金海英 《沙棘》2005,18(4):29-32
以沙棘籽为原料,考察了脱脂方式、提取温度、提取时间、乙醇浓度、料液比、提取次数等6个因素对原花青素提取率的影响。结果表明,超临界CO2萃取沙棘籽油后籽渣中原花青素含量要高于溶剂脱脂;从30℃至70℃原花青素提取率随温度升高而降低,但降低幅度不大,从70℃-90℃,提取率又略有升高;原花青素提取率随提取时间、提取次数、料液比的增加而增加,当提取时间、提取次数、料液比增加到一定程度后,原花青素提取率增加的不多或者基本不再增加;乙醇浓度以70%的乙醇溶液提取效果最好。  相似文献   

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