异叶蛇葡萄和蛇葡萄提取物抑制黄嘌呤氧化酶和脂质氧化酶的活性研究

蛇葡萄和异叶葡萄是湖北地区应用的具有抗病毒作用的药用植物,它们的抗氧化活性用酶的和非酶的体外抗氧化测定方法进行研究.实验结果显示,两种植物的提取物具有抑制黄嘌呤氧化酶和脂质氧化酶的活性;用Trolox等价抗氧化能力(TEAC)方法测定,显示两种提取物是ABTS· 自由基离子的清除剂,与葡萄种子提取物相比较,显示具有较强的抗氧化能力.     

三叶委陵菜对四氯化碳致小鼠肝损伤保护作用

目的：研究三叶委陵菜对四氯化碳（CCl4)致小鼠急性肝损伤的保护作用。方法：用三叶委陵菜给小鼠灌胃7d,观察对四氯化碳致小鼠肝损伤所引起血清谷丙转氨酶和谷草转氨酶升高,肝线粒体脂质过氧化物含量的影响。结果：三叶委陵菜能明显降低模型组的血清转氨酶、肝线粒体脂质过氧化物含量。结论：三叶委陵菜对小鼠肝脏的化学损伤有保护作用。     

Antihypercholesterolaemic and antioxidant activity assessment of some plants used as remedy in Turkish folk medicine

Ethanolic and aqueous extracts from five plant species used in Turkish traditional medicine were evaluated for in vivo hypercholesterolaemic and antioxidant activities: Agrostemma githago L., Potentilla reptans L., Thymbra spicata var. spicata L., Urtica dioica L. and Viscum album var. album L. We assayed the effects of the administration of plant extracts on serum total cholesterol, triglyceride, HDL-C, LDL-C, glucose, AST and ALT concentrations in mice fed with cholesterol-rich diet. In addition, plasma TAA, MDA and NO(x) levels in the same animals were assayed. All the aqueous plant extracts did not affect the serum cholesterol concentration. However, the ethanolic extracts of Agrostemma githago, Thymbra spicata and Viscum album decreased the serum cholesterol concentration in the mice fed with high-cholesterol diet without inducing any gastric damage. The ethanolic extracts of Thymbra spicata, Viscum album, Potentilla reptans and Urtica dioica and the aqueous extract of Agrostemma githago increased the serum HDL concentration, whereas the ethanolic extracts of Agrostemma githago, Thymbra spicata, Viscum album and Urtica dioica decreased the serum LDL-C concentration. Thymbra spicata and Viscum album were observed to decrease the serum triglyceride concentration. Among the plant extracts studied, the ethanolic extracts of Thymbra spicata significantly decreased the MDA level in mice. The ethanolic extract of Potentilla reptans increased in NO(x). None of these plants showed statistically prominent activity on plasma TAA. Results of the present study indicated that the ethanolic extracts of Agrostemma githago, Thymbra spicata and Viscum album showed potent hypocholesterolaemic activity in the mice fed with a diet containing high-cholesterol.     

Antioxidant, antimicrobial and cytotoxic activities of selected medicinal plants from Yemen

Ninety crude extracts, including dichloromethane, methanol and aqueous extracts from 30 medicinal plants used in the Yemeni ethnomedicine to treat common infections, were screened in vitro for antimicrobial activities against three Gram-positive bacteria and two Gram-negative bacteria, Candida maltosa and five opportunistic human fungal pathogens (two yeasts, three hyphomycetes). Most of the plants showed antibacterial activities. Extracts from Tamarindus indica flowers and Ficus vasta fruits have been the most active. Of the 30 plants tested, 13 showed antifungal activity (40%) against one ore more human pathogenic fungi. The strongest inhibition was exhibited by Azima tetracantha (fruits), Sansevieria ehrenbergii (fruits) and Solanum incanum (fruits). Ten methanol extracts, especially those of Acacia asak barks and Solanum nigrum fruits, showed effective free radical scavenging activities in the DPPH assay. Remarkable cytotoxic activity against FL-cells was shown only for five plants, among them Plicosepalus curviflorus (stems).     

Antioxidant activity of Porcelainberry (Ampelopsis brevipedunculata (Maxim.) Trautv.)

The stem and root of Porcelainberry (Ampelopsis brevipedunculata (Maxim.) Trautv.) (AB) was traditionally used as an anti-inflammatory, diuretic and anti-hepatotoxic agent in folk medicine. In this study, cell-free and cell culture systems were employed to investigate the antioxidant activity of the methanol extract of AB (MEAB). The cell-free system showed that the MEAB exhibited dose-dependent antioxidant activities against linoleic acid peroxidation and plasmid DNA oxidation. We also demonstrated that the MEAB possessed strong reducing power and scavenging effects of hydroxyl radicals and DPPH free radicals. The harmful effects of reactive oxygen metabolites on HepG2 cells and the possible antioxidant effects of the MEAB were also investigated. Pretreatment or cotreatment of HepG2 cells with the MEAB could significantly protect cells from H2O2-induced oxidative stress. This implies that the antioxidant effects in cell culture may result from the direct interaction between the MEAB and exogenous oxidant sources, as these occur in cell free systems, as well as from the induction of cellular stress gene expression. The antioxidant activity of the MEAB may partially explain its anti-inflammatory and anti-hepatotoxic effects.     

卷柏属药用植物的HPLC指纹特征研究

目的：建立卷柏属10种药用植物的HPLC指纹特征分析方法,对各个种的区别及这些种的相似性从所含化学成分的角度进行综合评价,为这10种药用植物的鉴定、品质分析及亲缘关系评价提供依据。方法：采用HPLC获得的色谱数据转化为HPLC指纹谱,据此对各样品进行鉴定与分析。结果：卷柏属10种药用植物均显示了它们明显的共性和各自的指纹特征；部分种在不同采收期、不同生境及不同产地的样品在指纹谱上存在一定差异。结论：该属10种药用植物具有2个重要的共有峰,5个峰的指纹数据可以作为主要的指纹特征数据,这些数据对于判断各种间亲缘关系的疏密,评价药材品质具有重要的参考价值。     

Antioxidant and anticancer activities of organic extracts from Platycodon grandiflorum A. De Candolle roots

This study examined the antioxidant and anticancer activities of the petroleum ether extracts from the roots of Platycodon grandiflorum A. DC, which is a plant used as both a herbal medicine and food in Asia. Extracts from Platycodon grandiflorum in petroleum ether were fractionated (fractions I-V) by silica gel column chromatography using gradient solvents (petroleum ether: ethyl ether, 9:1-5:5, v/v). The antioxidant activities of the fractions were evaluated in terms of their inhibition of lipid peroxidation as well as their free radical scavenging activity. Fraction II, which was extracted at an 8:2 mixture of petroleum ether and ethyl ether, exhibited the greatest antioxidant activity among the fractions. On the other hand, the cytotoxicity of each fraction, which was evaluated by the MTT assay using human cancer cell lines (HT-29, HRT-18 and HepG2), was greatest in fraction III, which was extracted with a 7:3 petroleum ether and ethyl ether mixture. Both fractions, II and III, were sub-fractionated by thin layer chromatography, and the sub-fractions each were screened for their antioxidant and anticancer activities. In addition, the antioxidant activity was closely related to the content of phenolic compounds, and the anticancer active fraction exhibited a typical UV absorbance spectrum of polyacetylene.     

Identification of trans-tiliroside as active principle with anti-hyperglycemic, anti-hyperlipidemic and antioxidant effects from Potentilla chinesis

Aim of the study

The present study was carried out to isolate and identify trans-tiliroside as principal compound with anti-hyperglycemic, anti-hyperlipidemic and antioxidant effects from Potentilla chinesis.

Materials and methods

A bioactive compound, trans-tiliroside was isolated from the ethanol extract of Potentilla chinesis and its administration dose was optimized and patented. The normal, alloxan-induced diabetic mice and streptozotocin-induced diabetic rats were used to evaluate the anti-hyperglycemic, anti-hyperlipidemic and antioxidant effects of trans-tiliroside from Potentilla chinesis. Biochemical parameters were assayed in blood samples of different groups of alloxan-induced diabetic mice and streptozotocin-induced diabetic rats.

Results

The level of fasting serum glucose levels, triglycerides (TG) and total cholesterol (TC) in alloxan-induced diabetic mice were significantly decrease after daily oral administration of trans-tiliroside in normal and diabetic mice at doses of 0.4, 0.8 and 1.6 mg/kg/day, for 15 days. Blood glucose level was significant decrease in STZ induced diabetic rats by trans-tiliroside (1.2 and 0.3 mg/kg body weight for 10 weeks). The content of TC, low density lipoprotein (LDL-C) and TG levels were decreased and high density lipoprotein (HDL-C) content was increased, so lipid metabolism was improved. Moreover, trans-tiliroside revealed antioxidant activity as shown by increased activities of superoxide dismutase (SOD), decreased level of malondialdehyde (MDA) in diabetic rats. Histological morphology examination showed that the trans-tiliroside restored the damage of pancreas tissues in rats with diabetes mellitus.

Conclusion

Trans-tiliroside, a constituent from Potentilla chinesis, revealed significant anti-hyperglycemic, anti-hyperlipidemic and antioxidant activities.     

显齿蛇葡萄叶总黄酮对苯并芘染毒小鼠血清和肝脏抗氧化酶的影响

目的:探讨显齿蛇葡萄叶总黄酮对苯并芘染毒小鼠血清和肝脏抗氧化酶的影响.方法:用显齿蛇葡萄叶总黄酮给小鼠灌服2周后,一次性灌胃苯并芘染毒,取血和肝脏测定超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、过氧化氢酶(CAT)、r-谷氨酰转肽酶(r-GT)活性和丙二醛(MDA)含量.结果:显齿蛇葡萄叶总黄酮能明显提高小鼠血清和肝脏中SOD、GSH-PX、CAT的活性,降低r-GT 活性及MDA 含量.结论:显齿蛇葡萄叶总黄酮具有抗氧化作用,可能是显齿蛇葡萄叶总黄酮的抗致癌物作用机制之一.     

Investigation of in vitro antioxidant activity of dihydromyricetin and flavonoids rich extract from vine tea(Ampelopsis grossedentata)

Background:Vine tea from fermented Ampelopsis grossedentata leaves has been used as a herbal tea and folk medicine in the southern region of China for hundreds of years.The aim of this investigation was to analyze the total flavonoids found in vine tea,including three bioactive flavonoids,and the total phenolic contents in the aqueous methanol extracts of 10 vine tea samples.In addition,this study also aimed to examine the antioxidant activity of dihydromyricetin and vine tea’s flavonoid-rich extract.Methods:The total flavonoids and total phenolic content assay of extracts from vine tea were performed by ultraviolet-visible spectroscopy and epoch microplate spectrophotometer,respectively.Three bioactive flavonoids were quantified simultaneously using high performance liquid chromatography.The antioxidant activity of dihydromyricetin and vine tea’s flavonoid-rich extract was evaluated in vitro using six different methods.Results:Vine tea contained a large number of flavonoids,with dihydromyricetin as its main constituent.The flavonoid-rich extract exhibited a significant scavenging effect on superoxide anion radicals,and on 3-ethylbenzthiazoline-6-sulphonic acid and 1,1-diphenyl-2-picrylhydrazyl radicals.It also possessed definite activity in lipid peroxidation inhibition,ferric reduction,and the moderation of Fe2+ion chelation ability.There was a significant negative correlation between dihydromyricetin content and antioxidant activity in the vine tea samples,including superoxide anion radical scavenging activity(P=−0.754,P<0.05),lipid peroxidation inhibition activity(P=−0.759,P<0.05),ferric-reducing antioxidant power(P=−0.843,P<0.01),respectively.Dihydromyricetin played a dominant role in the antioxidant activities of the flavonoid-rich extract.Conclusion:Vine tea’s flavonoid-rich extract could be used as a new antioxidant source to safeguard against oxidative stress.     

Evaluation of antioxidant and nitric oxide inhibitory activities of selected Malaysian medicinal plants

Methanol extracts of seven Malaysian medicinal plants were screened for antioxidant and nitric oxide inhibitory activities. Antioxidant activity was measured by using FTC, TBA and DPPH free radical scavenging methods and Griess assay was used for the measurement of nitric oxide inhibition in lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma)-treated RAW 264.7 cells. All the extracts showed strong antioxidant activity comparable to or higher than that of alpha-tocopherol, BHT and quercetin in FTC and TBA methods. The extracts from Leea indica and Spermacoce articularis showed strong DPPH free radical scavenging activity comparable with quercetin, BHT and Vit C. Spermacoce exilis showed only moderate activity but other species were weak as compared to the standards. In the Griess assay Lasianthus oblongus, Chasalia chartacea, Hedyotis verticillata, Spermacoce articularis and Leea indica showed strong inhibitory activity on nitric oxide production in LPS and IFN-gamma-induced RAW 264.7 cells. Extracts from Psychotria rostrata and Spermacoce exilis also inhibited NO production but this was due to their cytotoxic effects upon cells during culture.     

Biological activity and phytochemical analysis of three Indonesian medicinal plants, Murraya koenigii, Syzygium polyanthum and Zingiber purpurea

Extracts of Indonesian medicinal plants, Murraya koenigii, Syzygium polyanthum, and Zingiber purpurea were investigated for their biological activity. The presence of phytochemicals, cytotoxicity, and antimicrobial and antioxidant activities were investigated. Parts of M. koenigii, S. polyanthum, and Z. purpurea were extracted with ethanol. The extracts were evaluated for antimicrobial activity using the disc diffusion method, while antioxidant activity was determined with a 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay. Cytotoxicity was investigated using the brine shrimp lethality test, and phytochemical screening was performed using a standard method. M. koenigii leaf extract exhibited the most activity in the test microorganism activity index (AI), 0.38-1.25, when compared with standard drugs. S. polyanthum ripened fruit displayed significant antioxidant activity (90%) in comparison to ascorbic acid (95%). Z. purpurea rhizome extract possessed the highest cytotoxic effect with a LC(50) of 52 μg/mL. Phytochemical analysis revealed that carbohydrate, tannin, alkaloid, steroid, triterpenoid, and flavonoid were present in the extracts of M. koenigii leaves and twigs, S. polyanthum leaves and ripened and unripe fruits, and Z. purpurea rhizome, while saponin was only present in the S. polyanthum ripened fruit extract. Our work revealed that the M. koenigii leaves, S. polyanthum ripened fruit, and Z. purpurea rhizome extracts have potential as sources of new antimicrobial, antioxidant, and cytotoxic compounds, respectively.     

Antioxidant activities of coumarins from Korean medicinal plants and their structure–activity relationships

The aim of this work was to study the structure–activity relationships of the antioxidant activity of natural coumarins isolated from four Korean medicinal plants (1–17) and four purchased coumarins (18–21). The free radical scavenging and lipid peroxidation assays revealed that five phenolic coumarins, scopoletin (1), aesculetin (2), fraxetin (3), umbelliferone (18) and daphnetin (19), possessed considerable antioxidant activities. The coumarins having a catechol group, 2, 3 and 19, showed significant free radical scavenging activity and inhibitory effects on lipid peroxidation, indicating that the catechol group significantly contributed to the antioxidant activities of coumarins. In contrast, the sugar moiety markedly reduced the activities of coumarin glycosides. The results also demonstrate that the α‐pyrone ring of coumarins significantly enhanced the capacity of inhibiting oxidative reactions of coumarins. Copyright © 2009 John Wiley & Sons, Ltd.     

Screening of Malian medicinal plants for antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities

A total of 78 different extracts from 20 medicinal plants belonging to 14 plant families from Mali were tested for their antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities. Dichloromethane, methanol, water and ethanol extracts were used. TLC autobiography for antifungal activity was run with Cladosporium cucumerinum and Candida albicans. Extracts were also tested on the larvae of the mosquitoes Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus. Molluscicidal activities were established with the snails Biomphalaria glabrata, Biomphalaria pfeifferi and Bulinus truncatus. β‐Carotene and DPPH solutions sprayed on TLC plates were used for antioxidant and radical scavenging assays. Of the extracts investigated, 20% were antioxidant and radical scavengers, 19% fungicidal, 30% were larvicidal and 11% were molluscicidal. Three of the plant extracts, from Cussonia barteri (Araliaceae), Glinus oppositifolius (Aïzoaceae) and Lannea velutina (Anacardiaceae) gave positive responses in all four tests. Copyright © 2001 John Wiley & Sons, Ltd.     

Traditional medical uses of Drimia species in terms of phytochemistry,pharmacology and toxicology

Drimia genus includes plants that used from ancient time for various ailments such as dropsy, respiratory ailment, bone and joint complications,skin disorders, epilepsy and cancer. Toxic properties of some Drimia species also were noted by ancient scientists and these plants have been traditionally used for rat control. Bufadienolides have been identified as the main constituents in the genus of Drimia. Phenolics, sterols, protein and some of other phytochemicals have been also isolated from these plants. Pharmacological and clinical studies have strongly approved their effect on cardiovascular system. Extracts and compounds isolated from Drimia species showed biological activities such as antibacterial, antifungal, antiviral, antioxidant, anti-inflammatory and insecticidal effects throughseveral in vivo and in vitro studies. Moreover, cytotoxic and antitumor activities which may be related to bufadienolide content of these plants have been considered by many researchers. Traditional therapeutic values of these plants for treating respiratory and rheumatic ailments as well as skin disorders are needed to be validated through more researches. Toxic effects of these plants and isolated compounds have been investigated through several in vivo studies. Drimia plants and their isolated compounds have narrow therapeutic index, so patients should be prohibited from applying these plants without medical supervision and should be informed about the main intoxication symptoms before starting treatment. Moreover, interaction of Drimia plants with other constituents of traditional herbal mixtures as well as chemical and biological modalities for reducing toxicity of bufadienolide compounds can be subjected for future studies.     

Plant-insect interactions. I. Biological and phytochemical evaluation of selected plants.

Extracts from more than 325 different plants have been tested for their effects on larvae of Aedes aegypti, and from these initial tests, 16 plants were selected for further study. Extracts from plant parts of these 16 plants were screened using tlc and the results are tabulated along with the observed biological activity.     

黄芩脂质过氧化抑制率与有效成分含量的相关性研究

目的：对黄芩脂质过氧化抑制率与有效成分含量的相关性进行研究。方法：建立鼠肝微粒体脂质过氧化模型，以硫代巴比妥酸法评估黄芩及其主要成分黄芩素、黄芩苷和汉黄芩素不同比例组合样品在此模型中的抗脂质过氧化活性。结果：抗脂质过氧化活性以黄芩素最强，依次为黄芩苷和汉黄芩素。黄芩药材的IC₅₀在2.72～18.27 mg·L^-1。结论；黄芩的抗脂质过氧化活性除与有效成分的浓度有关外，还与其组成的比例密切相关。     

大叶蛇葡萄蛋白质组双向电泳分析

目的：利用双向电泳法研究大叶蛇葡萄活性成分蛋白表达。方法：采用Tris饱和酚提取和醋酸铵甲醇沉淀大叶蛇葡萄嫩叶中的蛋白质;运用双向电泳法分离蛋白质,并对扫描后的二维凝胶电泳图谱进行分析,得到蛋白质表征图谱。结果：根据各个样品间蛋白点灰度值的比值差异,选择了差异较大的7个蛋白点进行质谱鉴定,鉴定了其中两种蛋白,分别为Hypothetical Protein和Unnamed Protein Product。结论：双向电泳技术的应用为从分子水平研究大叶蛇葡萄活性成分蛋白表达奠定了良好的基础。     

Chemical composition analysis, antioxidant, antiglycating activities and neuroprotective effects of S. choloroleuca, S. mirzayanii and S. santolinifolia from Iran

This study was designed to examine antioxidant activities, antiglycating abilities and neuroprotective effects of methanolic extracts of Salvia choloroleuca, Salvia santolinifolia and Salvia mirzayanii from Iran. The extracts were screened for their possible antioxidant activities by several biochemical assays such as DPPH, FRAP, β-carotene bleaching and TEAC assays. HPLC analysis of these extracts led to the separation of a number of components such as catechine and rosmarinic acid. Based on our results, all these plants had antioxidant and antiglycating activities, among them S. choloroleuca seems to be the most effective one. Furthermore, these species not only showed no cytotoxic effects in neuron-like PC12 cells, but also protected them against oxidative stress-induced cell death, exerted by H(2)O(2). We further showed that these plants increase superoxide dismutase and catalase levels, reduce lipid peroxidation and up regulate hemeoxygenase-1 and glutamylcysteine synthetase proteins. This study raised the possibility of developing these plants as potential neuroprotective agents.     

灯心草抗氧化活性成分研究

采用DPPH法对两种灯心草属植物不同溶剂提取物进行抗氧化活性研究。结果表明灯心草乙酸乙酯提取物的抗氧化活性最强。评价了从该活性部位分离出的四个化合物清除DPPH自由基的活性，化合物3显示了一定的清除DPPH自由基的活性。