Cytotoxic sesquiterpenes from Magnolia kachirachirai

Bioassay-guided fractionation of the root wood of Magnolia kachirachirai (Kanehira & Yamamoto) Dandy (Magnoliaceae) led to the isolation of three new compounds, kachiraterpenol (1), (E)-2,3-bis(4-hydroxy-3-methoxyphenyl)prop-2-enal (15), and kachiranol (19), together with 27 known compounds, of which 4,4'-dihydroxy-3,3'-dimethoxybenzophenone (16) was isolated for the first time from a natural source. Their structures were elucidated by spectroscopic analysis. Two of these isolates, costunolide (2) and dehydrosaussurea lactone (4), showed cytotoxic properties against MCF-7, NCI-H460, and SF-268 cancer cell lines in vitro.     

华中五味子ISSR-PCR反应体系优化及引物筛选

系统研究了华中五味子ISSR PCR反应体系中的主要影响因子,确立华中五味子ISSR-PCR最适反应体系,并筛选出12条有效引物。单因子实验结果显示,华中五味子ISSR-PCR反应体系中各主要成分的适宜浓度范围为,Mg²⁺ 1.50~3.50 mmol·L^-1,dNTPs 0.10~0.35 mmol·L^-1,引物0.25~0.60 μmol·L^-1,Taq酶0.50~1.50 U。4因子3水平正交实验确立了最适反应体系,即20 μL体系中包含2.50 mmol·L^-1 Mg²⁺、0.20 mmol·L^-1 dNTPs、0.25 μmol·L^-1引物、1.50 U Taq酶、60 ng DNA模板、2.50 μL 10×PCR Buffer。本研究为华中五味子种质资源的评估及遗传多样性分析奠定基础。     

不同种源厚朴苗期性状变异及主成分分析

基于厚朴（Magnolia officinalis）作为一种传统中药植物及分布区域广、环境异质化程度明显的现象,采用田间种源实验,对分布在中国7个省的14个种源厚朴苗期的生长性状进行了观测分析。结果表明,不同种源厚朴的苗期生长性状差异显著。种源遗传力分析表明,苗高和单株叶面积两个性状的遗传力较高,分别为0.93、0.79,可认为以苗高和单株叶面积为主的种源多性状综合选择改良潜力巨大。相关性分析表明各性状间遗传相关、表型相关、环境相关均存在一定的相关关系,单株叶面积和地上部生长性状的遗传相关程度高于地下部生长性状,表型显著相关的性状组合数量和程度低于遗传相关。厚朴苗期种源选择的首选因子为各生物量及单数叶面积性状,辅助因子为苗高和地径。通过系统聚类分析,初步选定景宁、武夷山、龙胜、开县、城固、宁强及洋县的种源为优良厚朴种源。     

山茱萸不同栽培品种的 rDNA ITS 序列分析

为测定山茱萸（Cornus officinalis Sieb.et.Zucc.）核糖体DNA的ITS序列,对山茱萸不同栽培品种进行了ITS序列分析。通过实验筛选出一对引物,进行PCR扩增,对扩增产物提取纯化,双脱氧链终止法DNA测序。然后,利用DNAssist Version 2.0软件加手工校正确定ITS1-5.8S-ITS2序列,并进行ITS序列分析。获得了山茱萸的ITS1-5.8S-ITS2完全序列,ITS1为253bp,5.8S为156bp,ITS2为273bp,总共682bp。7种果型的山茱萸其5.8S基因序列显示高度的一致性,圆柱形果型、长梨形果型、椭圆形果型和纺锤形果型的ITS区序列完全一致,短圆柱形果型在ITS1区3′端及ITS2区5′端各有1个变异位点;短梨形果型在ITS1区5′端有3个变异位点;长圆柱形果型在ITS1区有5个变异位点。结果表明,ITS序列在山茱萸种内比较保守,有的栽培品种之间有较小的差异,此研究为中药山茱萸分子鉴定提供了科学依据。     

Population differentiation and gene flow within a metapopulation of a threatened tree, Magnolia stellata (Magnoliaceae)

We examined genetic differentiation among eight local populations of a metapopulation of Magnolia stellata using 10 nuclear and three chloroplast microsatellite (nSSR and cpSSR) markers and evaluated the influence of historical gene flow on population differentiation. The coefficient of genetic differentiation among populations for nSSR (F(ST) = 0.053) was less than half that for cpSSR (0.137). An isolation-by-distance pattern was detected for nSSRs, but not cpSSRs. These results suggest that pollen flow, as well as seed dispersal, has significantly reduced genetic differentiation among populations. We also examined patterns of contemporary pollen flow by paternity analysis of seeds from nine seed parents in one of the populations using the nSSR markers and found it to be greatly restricted by the distance between parents. Although most pollen flow occurred within the population, pollen flow from outside the population accounted for 2.5% of the total. When historical and contemporary pollen flows among populations were compared, the levels of pollen flow seem to have declined recently. We conclude that to conserve M. stellata, it is important to preserve the whole population by maintaining its metapopulation structure and the gene flow among its populations.     

Allelopathic potential of two sesquiterpene lactones from Magnolia grandiflora L.

The allelopathic effects of the two sesquiterpene lactones, costunolide and parthenolide, isolated from the leaves of Magnolia grandiflora L. were evaluated on the wheat (Triticum aestivum L.), lettuce (Lactuca sativa L.), radish (Raphanus sativus L.) and onion (Allium cepa L.). Seed germination of the test species was significantly reduced at 500 μg/ml by both compounds. Both sesquiterpenes showed pronounced inhibition of root length of the test species and the inhibitory effect was concentration-dependent. In addition, shoot growth of the four species was significantly inhibited at all the concentrations tested (10–500 μg/ml). Parthenolide reduced germination and inhibited seedling growth more than costunolide. Inhibition of root growth was generally greater than that of shoot growth. The results encourage the use of these sesquiterpenes as models for development of new herbicides.     

华中五味子干燥材料DNA提取方法的研究

目的：建立一套适合从华中五味子硅胶干燥的幼芽中提取高质量DNA的方法,为进一步开展分子生物学研究奠定基础。方法：比较SDS法、SIX-CTAB法、SDS-CTAB法以及经过作者改进的CTAB法,运用紫外光谱和电泳分析方法测定所得DNA样品的纯度与完整性。结果：四种方法中改进CTAB法所得DNA纯度最高,完整性好,其A260/A280值为1．81,A260/A230值为2．13,经稳定性试验证明该方法稳定。结论：改进CTAB法是一套适合从华中五味子硅胶干燥的幼芽中提取高质量DNA的方法。     

Identification of two markers linked to the sex locus in dioecious <Emphasis Type="Italic">Asparagus officinalis</Emphasis> plants

One hundred decamer primers of random-amplified polymorphic DNA were tested on dioecious Asparagus officinalis plants to identify sex-linked molecular markers. One primer (S368) produced two markers (S368-928 and S368-1178) in female plants. These two DNA markers were identified in 30 male and female plants, respectively, and a S368-928 marker was proved to be linked to the female sex locus. The female-linked S368-928 marker was sequenced and specific primers were synthesized to generate a 928 bp marker of sequence characterized amplified regions (SCAR) in female plants, SCAR₉₂₈. SCAR₉₂₈ could be used to correctly screen homozygous mm female plants of A. officinalis. However, results of Southern blot analysis suggest that the hybridization pattern of S368-928 was presented in both sex plants. This text was submitted by the authors in English.     

Effect of honokiol on activity of GAD65 and GAD67 in the cortex and hippocampus of mice

Honokiol, an active agent extracted from magnolia bark, has been reported that induces anxiolytic action in a mouse elevated plus-maze test. However, the mechanism of anxiolytic action induced by honokiol remains unclear. This study was to investigate the change in two forms of glutamic acid decarboxylase (GABA synthesized enzymes) GAD₆₅ and GAD₆₇ in the cortex and hippocampus areas while the anxiolytic actions induced by chronic administration of honokiol in mice. Mice treated with 7 daily injection of honokiol (1 mg/kg, p.o.) caused anxiolytic action which was similar to that was induced by 7 daily injection of diazepam (2 mg/kg, p.o.) in the elevated plus-maze test. In addition, the activity of hippocampal GAD₆₅ of honokiol treated mice was significantly increased than that of the vehicle or diazepam treated groups. These data suggest that honokiol causes diazepam-like anxiolytic action, which may be mediated by altering the synthesis of GABA in the brain of mice.     

Simultaneous analysis of diosgenin and sarsasapogenin in Asparagus officinalis byproduct by thin‐layer chromatography

Introduction – Asparagus officinalis L. has several biological activities including antifungal, antiviral and antitumoral activities due to the steroidal saponins. Normally diosgenin and sarsasapogenin are analysed separately by thin‐layer chromatography or high‐performance liquid chromatography (HPLC‐UV or HPLC‐ELSD), which is time‐consuming and expensive, so we need to find a rapid solution to this problem. Objective – To develop a sensitive, rapid and validated TLC method for simultaneous detection and quantification of diosgenin and sarsasapogenin. Methodology – Samples were prepared by extraction of A. officinalis with 70% aqueous ethanol to get steroidal saponins, and then hydrolysed using 36 mL 2 m hydrochloric acid for 3 h. The hydrolysis product was extracted with chloroform, and then analysed by TLC, the results of which were verified by HPLC and HPLC‐MS. Results – The retention factor (R_f) of diosgenin and sarsasapogenin on TLC plate were 0.49 and 0.6, respectively. After calculation from the regression equation of the standard curve, the contents of diosgenin and sarsasapogenin in the A. officinalis extract were 0.27–0.46 and 0.11–0.32%, respectively. Conclusion – The study showed that thin‐layer chromatography can be applied for the determination of diosgenin and sarsasapogenin in the oldest tissue of A. officinalis, and also can be conducted for screening of sapogenin in other plant or extracts. Copyright © 2010 John Wiley & Sons, Ltd.