Antioxidative responses to different altitudes in leaves of alpine plant Polygonum viviparum in summer

Mountain environmental stresses result in increased formation of hydrogen peroxide (H₂O₂) and accumulation of malondialdehyde (MDA) in leaves of Polygonum viviparum. The activities of several antioxidative system enzymes such as superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), peroxidase (POD, EC 1.11.1.7), glutathione reductase (GR, EC 1.6.4.2), dehydroascorbate reductase (DHAR, EC 1.8.5.1) and the contents of several non-enzymatic antioxidants such as reduced form of ascorbate (ASC), dehydroascorbate (DHA), reduced glutathione (GSH), and oxidized glutathione (GSSG) were investigated in leaves of P. viviparum, which were collected from three altitudes (2,200, 3,200, and 3,900 m) of Tianshan Mountain in China. The activities of these four antioxidative enzymes were accompanied by increases of H₂O₂ levels from 2,200 to 3,200 m. However, the activities of CAT and POD were decreased, whereas the activities of SOD and GR continually increased at 3,900 m. Analyses of isoforms of SOD, CAT, POD, and GR showed that the leaves of P. viviparum exposed different altitude conditions are capable of differentially altering the intensity. Additionally, two new isoforms of SOD were detected at 3900 m. A continual increase in the ASC, ASC to DHA ratio, GSH and GSH/[GSH + GSSG] ratio, and the activity of DHAR were observed in leaves of P. viviparum with the elevation of altitude. These results suggest that the higher contents of ASC, GSH as well as an increase in reduced redox state may be essential to antioxidation processes in the leaves of P. viviparum, whereas antioxidant enzymes system is a cofactor in the processes.     

酶解法提取纯化虎杖提取物中自藜芦醇的工艺研究

本文对虎杖提取物中虎杖苷的酶解条件及苷元白藜芦醇的提取纯化工艺进行研究,以样品中自藜芦醇的含量为指标,对纤维素酶、β-葡萄糖苷酶、复合酶进行筛选,结果表明以复合酶的水解效率最高:采用正交实验对影响复合酶酶解的因素:加酶量、温度、酶解时间进行考察;并对酶解后提取物中自藜芦醇的提取纯化工艺进行研究.得出如下较理想的酶解条件和提取纯化工艺:虎杖提取物,加水(pH 5)10倍,加20%的复合酶,于50℃保温24 h;酶解后的提取物经水、乙醇-水、碱溶液分步溶解沉淀,得白藜芦醇粗品,含量可达65%,工艺稳定可行.     

7种蓼属植物繁育系统的初步研究

观测了7种蓼属植物的花部形态特征,并运用花粉-胚珠比和杂交系数的方法对其繁育系统进行了初步研究。结果表明这7种蓼属植物的繁育系统应为自交和异交并存的混合交配型。P/O比与花序长度和花朵直径有明显的正相关关系,异型花的P/O比要明显高于同型花的P/O值。     

二苯乙烯苷抗动脉粥样硬化的作用和机制

二苯乙烯苷是中药何首乌中主要的水溶性生物活性成分。大量研究表明,二苯乙烯苷能够通过调脂、抗氧化、抗炎、舒张血管及增强免疫力等作用而抑制动脉粥样硬化的发生和发展,作为抗动脉粥样硬化的一种有效成分极具研究价值。但目前对其抗动脉粥样硬化的潜在作用机制还不完全清楚,本文就二苯乙烯苷在调节脂质、抗氧化、降低炎性反应等方面作用和机制作一综述。     

圆瓣姜花根茎挥发油的化学成分

利用水蒸汽蒸馏法提取圆瓣姜花根茎挥发油,运用毛细管气相色谱-质谱联用法对挥发油进行了分析,分离出60个峰,鉴定了其中的51种成分,所鉴定成分占挥发油总量的97.32%,其主要化学成分为单萜及倍半萜类化合物。     

东方蓼的染色体核型分析

目的:对药用植物东方蓼的染色体数目、核型、体积等进行了研究。方法:采用常规制片方法,结合显微摄影对染色体的数目进行统计分析。结果:东方蓼体细胞染色体数目2n=22,相对长度组成2n=22=10M2+12M1;核型公式为K(2n)=2X=22=20m+2M;全体染色体总长19.16μm,长臂总长10.93μm,核型不对称系数(AS.K%)为57.00%,属于"1A"型,全体染色体总体积为20.30μm3。结论:东方蓼体细胞染色体的数目、核型、体积等清晰准确。     

Antimicrobial activity and phytochemical analyses of Polygonum aviculare L. (Polygonaceae), naturally growing in Egypt

Polygonum aviculare (Polygonaceae) is an herb commonly distributed in Mediterranean coastal regions in Egypt and used in folkloric medicine. Organic and aqueous solvent extracts and fractions of P. aviculare were investigated for antimicrobial activities on several microorganisms including bacteria and fungi. Phytochemical constituents of air-dried powered plant parts were extracted using aqueous and organic solvents (acetone, ethanol, chloroform and water). Antimicrobial activity of the concentrated extracts was evaluated by determination of the diameter of inhibition zone against both Gram-negative and Gram-positive bacteria and fungi using paper disc diffusion method.Results of the phytochemical studies revealed the presence of tannins, saponins, flavonoids, alkaloids and sesquiterpenes and the extracts were active against both Gram-negative and Gram-positive bacteria. Chloroform extract gave very good and excellent antimicrobial activity against all tested bacteria and good activity against all tested fungi except Candida albicans. Structural spectroscopic analysis that was carried out on the active substances in the chloroform extract led to the identification of panicudine (6-hydroxy-11-deoxy-13 dehydrohetisane).Evaluation of the antimicrobial activity of panicudine indicated significant activity against all tested Gram-negative and Gram-positive organisms. Panicudine displayed considerable activity against the tested fungi with the exception of C. albicans. Antimicrobial activity of the extracts was unaffected after exposure to different heat treatments, but was reduced at alkaline pH. Studies of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of panicudine on the tested organisms showed that the lowest MIC and the MBC were demonstrated against Salmonella paratyphi, Bacillus subtilis and Salmonella typhi and the highest MIC and MBC were against Staphylococcus aureus.     

不同地理来源头花蓼的遗传多样性与没食子酸含量相关性分析

应用ISSR-PCR和HPLC方法研究了头花蓼的遗传多样性与没食子酸之间的关系。ISSR结果显示居群总的遗传变异较大(Ht=0.2746),居群内的遗传变异较小(Hs=0.0804),居群间的遗传分化大于居群内的遗传分化。没食子酸含量经SPSS17.0分析显示,各居群间和居群内个体的没食子酸含量差异较大,居群间没食子酸含量范围在0.1738%～0.3306%,其中云南腾冲县,贵州台江县、纳雍县、余庆县、晴隆和毕节县居群间没食子酸含量差异均达到显著水平。通过对头花蓼48个地理居群的遗传多样性与没食子酸含量的相关分析,表明云南腾冲,贵州台江、毕节市亮岩镇、晴隆、盘县居群的遗传多样性指数、没食子酸含量较高,不仅可以作为人工育种的选育材料,而且对于头花蓼种植适生地区划研究具有很好的参考价值。     

蓼属头状蓼组rDNA-ITS的序列扩增及分析

以贵州境内蓼属头状蓼组6种(含1变种)植物为材料,对其rDNA的内转录间隔区(ITS)序列进行PCR扩增,得到6种植物的ITS序列,分别为:赤胫散2个居群(Polygonum runcinatum var.sinense,GenBank登录号FJ606887、FJ648802),平卧蓼(P.strindbergii,GenBank登录号FJ648803 ),尼泊尔蓼(P.nepalense,GenBank登录号FJ648804),羽叶蓼(P.runcinatum,GenBank登录号FJ648805),火炭母(P.chinense,GenBank登录号FJ648806)和头花蓼(P.capitatum,GenBank登录号FJ648807).其中赤胫散与平卧蓼的ITS序列为首次报道.序列分析结果表明,蓼属头状蓼组6种植物ITS序列总长度为661～666 bp,ITS1区序列长度为243～246 bp,5.8 S rDNA区序列长度165 bp,ITS2区序列长度253～258 bp,6种植物的差异主要集中在ITS1和ITS2区.聚类分析显示,6种头状蓼组植物具有共同起源,结果支持赤胫散从羽叶蓼变种上升为独立物种.     

Assessment of genetic diversity of native species in Izu Islands for a discriminate choice of source populations: Implications for revegetation of volcanically devastated sites

In using native species for revegetation, it is necessary choose source populations carefully to reduce the risk of planting suboptimal germplasm. To make preliminary recommendations for native species to use in the revegetation of a volcanically devastated area on Miyake Is., Japan, we investigated the genetic variation of Alnus sieboldiana, Miscanthus sinensis ssp. condensatus, and Polygonum cuspidatum var. terminalis in the Izu Islands and on the Izu Peninsula based on chloroplast DNA (cpDNA) sequence variations and amplified fragment length polymorphisms (AFLPs). The amount and pattern of differentiation differ between organelle and nuclear markers, suggesting the necessity of evaluation based on both types of markers. Within-population diversity did not vary among populations, suggesting that it does not need to be considered in the choice of a source population. The pattern and degree of differentiation varied among species, and geographical proximity did not necessarily accord with genetic similarity, suggesting that the site of an appropriate source population varies among species and should be determined empirically rather than by assuming that close proximity predicts genetic similarity. The Izu Peninsula populations deviated from the island populations in all species. Comparison of cpDNA sequences with those of related species indicates the possibility of hybridization with related species on the Izu Peninsula, suggesting that seeds collected from populations where related species live sympatrically should not be used for revegetation. These findings indicate the need to assess the genetic diversity empirically by using organelle and nuclear markers to avoid unintended consequences of genetic mixing associated with revegetation.