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1.
The effect of the methanol extract from aerial parts of Bupleurum fruticescens on the release of eicosanoids and hydrolytic enzymes was determined on in vitro cell systems. The extract had a significant effect on 5-lipoxygenase (5-LOX) activity, inhibiting both LTB4 and 5(S)-HETE production with IC50 values of 112 microg/ml and 95 microg/ml, respectively. At concentrations of 200 microg/ml, the extract also inhibited cyclooxygenase-1 (90%) and elastase activities (54%). The 12-LOX activity in intact platelets was not affected; a fact, which suggests that phospholipase A2 (PLA2) activity, is not modified by the extract.  相似文献   

2.
The antiinflammatory effect of the aqueous leaf extract of Byrsocarpus coccineus was evaluated using the carrageenan and egg albumin induced rat paw edema, xylene induced mouse ear edema and formaldehyde induced arthritis inflammation tests. The extract administered orally at doses of 50, 100, 200 and 400 mg/kg b.w produced a significant (P<0.05) dose dependent inhibition of edema formation in all four methods used. The results obtained suggest that the aqueous leaf extract of B. coccineus is endowed with effective antiinflammatory activity mediated via either inhibition of phospholipase A(2) (PLA(2)) activity or cyclooxygenase cascade and by blocking the release of vasoactive substances (histamine, serotonin and kinins). These findings seem to justify the use of the plant in traditional African medicine in the treatment of inflammation, including arthritic conditions.  相似文献   

3.
通过对秤锤树种子甲醇浸提液的生物测定研究,探讨了秤锤树种子休眠与种子内源抑制物的关系。研究结果表明:秤锤树种子不同浓度的甲醇浸提液(25%、50%、75%、100%)对白菜籽发芽率、苗高和根长的生长均有一定的抑制作用。而且,浓度越高,抑制作用越明显,其中用25%、50%、75%和100%的浸提液处理白菜籽,其发芽率分别为82%、77%、68%和58%,根长分别比对照大约降低了27%、47%、67%和%74%,苗高分别比对照大约降低了20%、40%、60%和80%。表明秤锤树种子中存在某些抑制种子萌发的物质成分,这也是导致秤锤树种子深休眠的主要原因之一。  相似文献   

4.
Choi EM  Hwang JK 《Fitoterapia》2005,76(2):194-203
Traditional Indonesian medicinal plants were screened for their inhibitory effects on the nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and for the antioxidant activity through the evaluation of free radical scavenging effect and reducing power. The results of screening indicated that 50 methanolic extracts inhibited (>50%) lipopolysaccharides (LPS)-induced NO release from RAW264.7 cells at 50 microg/ml, with 18 having greater than 100% inhibition. At 200 microg/ml, 61 methanol extracts exhibited inhibitory activity (>50%), with 45 showing greater than 100% inhibition. In addition, the free radical scavenging effects of 6 methanolic extracts were found to be more than 50% for extract concentration of 0.5 mug/ml. The results indicate that the extracts contain active compounds that inhibit NO release and scavenge free radical.  相似文献   

5.
桉叶抗氧化物的提取与抗氧化性质研究   总被引:4,自引:0,他引:4  
以广林9号桉叶粉为材料,通过单因素和正交实验,确定最佳提取条件为50%乙醇、料液比1:20、50℃提取1h;抗氧化稳定性研究表明:光照、空气和温度对提取物抗氧化活性均有较大的影响,而pH值对其影响较小;对酚类物质的含量进行测定,表明提取物中酚类物质的含量与抗氧化效果成正相关;以有机溶剂对上述提取物进行萃取,抗氧化效果为正丁醇萃取物〉乙酸乙酯萃取物〉水萃取物〉石油醚萃取物;然后比较了不同浓度乙醇作为洗脱剂对正丁醇萃取物分离的影响,以50%和70%乙醇洗脱成分活性最强。  相似文献   

6.
Han L  Fu Y  Cole AJ  Liu J  Wang J 《Fitoterapia》2012,83(4):721-731
It is difficult to develop injectable sustained delivery systems for herbal medicines because of their composition complexity. Encapsulating various compounds with different physiochemical properties and achieving their synchronized and sustained release seem too hard to realize. In this paper, an injectable nanoparticulate system based on an mPEG-PLGA-mPEG (PELGE) platform was prepared for co-encapsulation and sustained release of four active components (ginkgolides A, B, C and bilobalide) in Ginkgo biloba extract. Different carriers were screened by macrophage uptake experiment for their ability to be long-circulation. Drug loaded nanoparticles were prepared with 10% PEG(2000) modified PLGA by a co-precipitation method. The encapsulation efficiency of the total ginkgo terpenes (GT) in the optimal formulation was 78.84±2.06% with a loading dose of 11.90±0.31mg/150mg PELGE. The particles exhibited a spherical shape with a mean diameter of 123.3±44.0nm and zeta potential of -30.86±2.49mV. Sustained and synchronized release of the four components from PELGE nanoparticles was observed both in vitro and in vivo, which was mainly contributed to the long circulation of PEGylated nanoparticles and the slow degradation of PLGA. The half-life time of the four terpenoid compounds were also significantly improved by incorporation into PELGE nanoparticles. The results indicate that a PELGE nanoparticle is a promising carrier system for sustained and synchronized release of herbal medicines containing multiple components.  相似文献   

7.
The Euphorbia hirta ethanolic extract (EH A001) was found to possess a prominent anti-anaphylactic activity. A preventive effect of EH-A001 given by oral route at dose from 100 to 1000 mg/kg was observed against compound 48/80-induced systemic anaphylaxis. At the same range of dose, EH-A001 inhibited passive cutaneous anaphylaxis (PCA) in rat and active paw anaphylaxis in mice. A suppressive effect of EH-A001 was observed on the release of TNF-alpha and IL-6 from anti-DNP-HSA activated rat peritoneal mast cells.  相似文献   

8.
Chen BQ  Cui XY  Zhao X  Zhang YH  Piao HS  Kim JH  Lee BC  Pyo HB  Yun YP 《Fitoterapia》2006,77(4):262-267
The present study was undertaken to investigate the antioxidative and antiinflammatory activities of the ethanolic extract of seeds of Torreya grandis (EST). Exposure of human dermal fibroblasts to the extract at 50 and 250 microg/ml showed significant protective effect against hydrogen peroxide (300 microM). EST not only protected cell survival from H(2)O(2)-induced toxicity, but also inhibited the H(2)O(2)-induced LDH release significantly. It was also found that EST at 100 and 1000 microg/ml showed scavenging activities of radicals and reactive oxygen species with 29.8% and 100.0% of inhibition against DPPH radical and 41.2% and 98.4% against superoxide radicals in the xanthine/xanthine oxidase system, respectively. Topically applied EST dose-dependently inhibited arachidonic acid (AA)- and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema in mice.  相似文献   

9.
为了解夹竹桃叶提取液对红蜡蚧若虫的防治效果,以无氯清水和95%乙醇为溶剂,提取得到夹竹桃叶水提液和夹竹桃叶醇提液,对红蜡蚧初孵若虫涌散期的防治效果进行初步研究。结果表明:夹竹桃叶提取液对红蜡蚧初孵若虫有较好的防治效果,随着提取液浓度的增加,防治效果增强;随着处理时间的延长,死亡率上升。夹竹桃叶水提液1∶10、夹竹桃叶醇提液1∶10浓度配比的防治效果最好。  相似文献   

10.
Liu H  Yang X  Ren T  Feng Y  Xu H 《Fitoterapia》2005,76(7-8):666-670
Antioxidant activity of the ethanol extract of Erigeron breviscapus (EEEB) were studied by using neuron oxidative injury model induced by superoxide radical. EEEB at the dose of 10-140 mug/ml reduced significantly the lipid peroxidation levels and lactic dehydrogenase (LDH) release from neuron exposed to superoxide radical (generated by xanthine and xanthine oxidase). These results suggest that neuroprotective actions of EEEB may be due to its antioxidant or radical scavenging activity.  相似文献   

11.
The aqueous extract of Viscum album leaves showed a significant coronary vasodilator activity on the Langendorff's isolated and perfused heart model. The data obtained suggest that the aqueous extract of V. album contains some biologically active principles that may act as inducers of the nitric oxide/soluble guanylate cyclase pathway.  相似文献   

12.
Pueraria mirifica and its extracts are widely used as the ingredient(s) in many rejuvenating products. Up to now, the extract of P. mirifica roots that has been used in most studies, is the alcoholic extract. In the present study, we investigated the estrogenic activity using uterotropic and MCF-7 cell proliferation models of the dichloromethane extract as well as the water extract which was obtained from partitioning the ethanolic extract. The results indicated that among the three extracts, i.e. the ethanolic extract (PM1), the water extract (PM2) and dichloromethane extract (PM3), PM3 exhibited the most potent estrogenic activity in both models, followed by PM1. The extracts produced uterotropic activity associated with the increase of water content while uterotropic activity of 17beta-estradiol was related to the increase of muscle mass. The two isoflavonoids, genistein and daidzein, were not the major active phytoestrogens involving the estrogenic activity of these extracts.  相似文献   

13.
外来树种火炬树化感作用的研究   总被引:1,自引:1,他引:0       下载免费PDF全文
以盐肤木和黄栌为参照树种,用火炬树树叶水浸提液、林下土壤水浸提液浸种24 h,研究了浸提液对侧柏、油松、香椿、臭椿、小麦、小白菜种子萌发及幼苗生长的影响,研究了火炬树的化感作用。结果表明:火炬树完整鲜叶水浸提液处理小白菜种子,其发芽率和发芽势分别为88.0%、82.5%,与对照发芽率(94.0%)和发芽势(91.5%)无显著差异,而破碎鲜叶水浸液则极显著影响小白菜的发芽率和发芽势,分别降低为24.8%和5.0%;火炬树完整鲜叶和破碎鲜叶水浸液都能促进小白菜苗高生长,但都抑制小白菜胚根的伸长。与鲜叶相比,火炬树干叶水浸提液的化感作用明显降低。火炬树破碎鲜叶水浸提液极显著影响小麦发芽率,分别比对照的发芽率和发芽势降低11.0%和83.5%,干叶水浸提液则不影响小麦的发芽率,为95.0%,但发芽势比对照降低23.0%。与盐肤木和黄栌相比,火炬树破碎鲜叶水浸提液对小麦幼茎及胚根生长的抑制作用最强。火炬树破碎鲜叶水浸提液对4个乡土树种的种子萌发产生了不同程度的抑制作用,对香椿及臭椿发芽率的抑制作用极显著。火炬树破碎鲜叶水浸提液对4个树种的苗高以及油松苗胚根的伸长没有显著影响,但却极显著地抑制了侧柏、香椿及臭椿胚根的伸长。火炬树林下表层土壤水浸提液对小麦幼苗的生长没有抑制作用,能明极显著促进香椿的生长;处理55 d时,香椿苗平均高为8.63 cm,极其显著高于对照(5.14 cm)。  相似文献   

14.
Chronic toxicity of Gynostemma pentaphyllum   总被引:4,自引:0,他引:4  
The effect of water extract of Gynostemma pentaphyllum was evaluated on 6-month chronic toxicity in Wistar rats. Control group received orally 10 ml kg(-1) day(-1). The extract was orally given to the five treatment groups at the doses of 6, 30, 150, 750 and 750 mg kg(-1) day(-1) for 24 weeks. The last group served as the recovery group. The results showed that the extract did not produce any significant dose-related changes. Therefore, it is concluded that the extract of G. pentaphyllum at the given doses did not produce any significant toxic effect in rats during 6-month period of the treatment.  相似文献   

15.
采用Caco-2细胞模型,分析了青钱柳Cyclocarya paliurus叶水提物、醇提后的水提物、95%醇提物、乙酸乙酯萃取物和正丁醇萃取物5种不同提取物对Caco-2细胞活力的影响及对Caco-2细胞上麦芽糖酶、蔗糖酶、乳糖酶3种二糖酶活性的抑制作用。结果表明,5种不同提取物中除95%醇提物对Caco-2细胞活力产生一定影响外,其余4种提取物对Caco-2细胞基本无毒性,在200 mg·L-1浓度提取物范围内培养24~72 h后细胞仍能保持较高活力;对3种二糖酶活性抑制作用效果最好的为醇提后的水提物,尤其是对蔗糖酶和乳糖酶的抑制作用更为明显,最高的抑制率分别达到76.35%和60.13%,其次为乙酸乙酯萃取物,对乳糖酶的抑制率最高达54.41%。从青钱柳叶不同方法提取物的制备流程说明多糖类或中等极性的黄酮甙类有可能是青钱柳叶中抑制二糖酶活性的主要组成成分。  相似文献   

16.
A major problem within forest industry is unwanted browsing on seedlings from mammalian herbivores. The aim of this study was to evaluate the effects of birch bark extracts as repellents towards fallow deer. Birch bark was extracted in a conventional way with ethanol as solvent at ambient temperature and with a new method, liquid CO2 extraction. An analysis of the ethanol-extracted birch bark showed that it contained large amounts of terpenoids, of which the most abundant was betulin. In seven different treatment trials, we used 15 individually handled fallow deer. To investigate the binary taste preferences, birch bark extract was added to food and presented in two bowls in typical two-choice tests. We found that the amount of a food type consumed during a trial and the number of shifts between food bowls were dependent on the amount of the birch extract the food contained. Concentrations of above 1 % by dry weight of birch extract acted as a repellent. In addition, such concentrations produced shorter feeding bouts by a greater willingness to change bowls. Therefore, our conclusion is that birch bark extract acts as a repellent towards fallow deer and is therefore likely to act as a repellent against other deer species. In addition, we show that birch bark extract produced by the new and more environmentally sustainable method employing liquid CO2 mixed with ethanol has the same repellent effect as the traditional ethanol extraction.  相似文献   

17.
The aqueous extracts of Datura fastuosa leaves and seeds were evaluated for the analgesic effect on acetic acid-induced writhing and hot plate reaction in mice. According to the results, D. fastuosa leaves and seeds extracts at oral doses of 400 and 800 mg/kg are effective as analgesic. The analgesic activity of leaf extract is reduced by naloxone but not that of seed extract.  相似文献   

18.
In recent years, dietary fatty acids have been extensively evaluated for nutritional as well as cosmetic benefits. Among the dietary fats, the omega-3 (ω3) and omega-6 (ω6) forms of polyunsaturated fatty acids (PUFAs) have been found to exhibit many biological functions in the skin such as prevention of transepidermal water loss, maintenance of the stratum corneum epidermal barrier, and disruption of melanogenesis in epidermal melanocytes. In this study, we examined the effect of chia seed extract, high in ω3 (linolenic acid) and ω6 (linoleic acid) PUFAs, for its capacity to affect melanogenesis. Chia seed extract was shown to inhibit melanin biosynthesis in Melan-a cells; however, linoleic and α-linolenic acids alone did not effectively reduce melanin content. Further investigation demonstrated that chia seed extract in combination with pomegranate fruit extract had a synergistic effect on the inhibition of melanin biosynthesis with no corresponding effect on tyrosinase activity. Investigation of the possible mechanism of action revealed that chia seed extract downregulated expression of melanogenesis-related genes (Tyr, Tyrp1, and Mc1r), alone and in combination with pomegranate fruit extract, suggesting that the inhibition of melanin biosynthesis by a novel combination of chia seed and pomegranate fruit extracts is possibly due to the downregulation of gene expression of key melanogenic enzymes.  相似文献   

19.
桑叶总黄酮的提取及其抑菌活性研究   总被引:2,自引:0,他引:2  
以抑菌活性为评价指标,对桑叶总黄酮的提取工艺进行了优化,并对优化条件下得到的粗提物采用不同溶剂进行分级提取和定性分析,测定了各萃取物的总黄酮含量,考察了萃取物对大肠杆菌、金黄色葡萄球菌的抑菌圈直径、最低抑菌浓度,选取抑菌效果最佳的萃取物进行了稳定性实验。结果表明,桑叶总黄酮提取的最佳条件为:温度70℃,乙醇体积分数70%,提取时间4 h,固液比1∶30(g∶mL);抑菌效果最佳的为乙酸乙酯萃取物,且乙酸乙酯部分对温度和紫外线照射的影响均具有良好的稳定性。  相似文献   

20.
几种树种水浸液对杉木叶片硝酸还原酶的效应   总被引:1,自引:0,他引:1  
采用完全随机区组设计,用马尾松(Pinusmassoniana)、木荷(Schimasuperba)、赤楠(Syzygiubuxifolium)、杉木(Cunninghamialanceolata)的枝叶1∶6浓度水浸液和清水共5个不同处理浇灌盆栽的杉木幼苗,2a后对其叶片的硝酸还原酶活性进行测定。结果表明,经过几种杉木伴生种水浸液处理2a后杉木的硝酸还原酶活性比杉木水浸液及清水处理的有较大程度的提高,其中经过马尾松水浸液处理的杉木叶片的硝酸还原酶活性最高,而经杉木枝叶水浸液处理的硝酸还原酶活性最低。  相似文献   

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