环草石斛野生植株与组培苗总生物碱和多糖含量的比较

对贵州产野生环草石斛植株和组培苗中有效成分(总生物碱和多糖)的含量进行了测定和比较分析。结果表明:不同来源的环草石斛中总生物碱含量顺序为:组培苗>野生样品>市售样品;多糖的含量顺序为:野生样品≥组培苗>市售样品。环草石斛组培苗具备直接提取原药成分的可能性。该研究结果为环草石斛次生代谢产物的工业化生产开辟了新途径并提供了基础数据。     

(-)-Veranigrine, a new steroidal alkaloid from Veratrum nigrum L

A new steroidal alkaloid, (-)-veranigrine (1) was isolated from the roots and rhizomes of Veratrum nigrum L. By means of spectroscopic methods its structure was established as (20S, 25S)-iminocholesta-5,22(N)-diene-1beta,3beta-diol.     

不同培养条件对环草石斛愈伤组织中次生代谢产物的影响

[目的]探索环草石斛生长与其主要的次生代谢产物——石斛碱和石斛多糖积累之间的关系。[方法]用苯酚-浓硫酸法和溴甲酚绿酸性染料比色法测定了不同培养条件对环草石斛愈伤组织中的多糖和总生物碱含量的影响。[结果]环草石斛悬浮培养的愈伤组织生长曲线呈"S"型。在光照条件下,环草石斛悬浮培养的愈伤组织中总生物碱和多糖含量的积累与其生长基本同步,光照有利于悬浮培养愈伤组织的生长和多糖的积累;在暗培养条件下,愈伤组织生长缓慢,多糖的积累不与其生长同步,但暗培养却可以提高愈伤组织中总生物碱的含量。[结论]环草石斛生长与其主要的次生代谢产物——总生物碱和石斛多糖积累之间有着密切的关系,不同培养条件对环草石斛中次生代谢产物具有一定的影响。     

不同土壤类型烟叶组织结构及化学成分的差异比较

为探寻广东南雄紫色土、沙泥田、牛肝土田3种土壤类型上所种烤烟香气风格差异的原因,以粤烟98的中部叶为试验材料,对烟叶生长发育过程中的组织结构、烤后烟叶主要生物碱及常规化合物等化学成分进行了对比分析。结果表明,紫色土上所种烤烟栅栏组织开始快速增厚的时期较早,沙泥田上所种烤烟栅栏组织前期增厚较快而后期较慢,牛肝土田烟叶栅栏组织、海绵组织和叶片厚度均最大,但在前期生长较慢。烟叶烤后（C3F）总糖、还原糖的含量均以沙泥田最高,牛肝土田次之,紫色土最低;而糖碱比则相反。沙泥田上所种烟叶烤后新烟碱含量最高,假木贼碱含量最低;牛肝土田上所得烤烟降烟碱含量最高,新烟碱含量最低;紫色土上烤烟的降烟碱含量最低,而假木贼碱和烟碱含量最高,适于生产优良浓香型香烟。     

小檗属植物中生物碱成分及药理活性研究概述

本文对小檗属植物的生物碱成分及药理活性等方面的研究进行了概述。研究结果表明,小檗属植物主要含有效成分为生物碱类物质,常见类型为原小檗碱型及双苄基异喹啉型生物碱;在药理活性方面,小檗属植物具消炎抗菌、降血压、降血糖、抗心律失常、抗癌等作用。     

Subereamolline A as a Potent Breast Cancer Migration, Invasion and Proliferation Inhibitor and Bioactive Dibrominated Alkaloids from the Red Sea Sponge Pseudoceratina arabica

A new collection of several Red Sea sponges was investigated for the discovery of potential breast cancer migration inhibitors. Extracts of the Verongid sponges Pseudoceratina arabica and Suberea mollis were selected. Bioassay-directed fractionation of both sponges, using the wound-healing assay, resulted into the isolation of several new and known brominated alkaloids. Active fractions of the sponge Pseudoceratina arabica afforded five new alkaloids, ceratinines A–E (2–6), together with the known alkaloids moloka’iamine (1), hydroxymoloka’iamine (7) and moloka’iakitamide (8). The active fraction of the sponge Suberea mollis afforded the three known alkaloids subereamolline A (9), aerothionin (10) and homoaerothionin (11). Ceratinine B (3) possesses an unprecedented 5,7-dibrominated dihydroindole moiety with an epoxy ring on the side chain of a fully substituted aromatic moiety. Ceratinines D (5) and E (6) possess a terminal formamide moiety at the ethylamine side chain. Subereamolline A (9) potently inhibited the migration and invasion of the highly metastatic human breast cancer cells MDA-MB-231 at the nanomolar doses. Subereamolline A and related brominated alkaloids are novel scaffolds appropriate for further future use for the control of metastatic breast cancer.     

均匀设计法提取附子总生物碱的工艺研究

[目的]筛选附子中总生物碱的最佳提取工艺寻找适合工业化生产的操作程序。[方法]采用均匀设计法对中药附子中总生物碱进行提取,以样品总生物碱量为评价指标探讨乙醇提取的浓度、用量和提取时间对总提取量的影响,将优选出的最佳提取工艺条件,与其他文献中所使用的方法进行比较,判断是否适合工业化生产。即用TS-NS系列提取浓缩机组对附子进行提取浓缩,冷冻干燥后溶解并用滴定法测定测定附子中总生物碱的含量。[结果]最佳工艺条件为：提取剂乙醇浓度为85%,附子粒径60目,乙醇用量为药材量的9倍（1∶9,g∶m l）,提取时间为2 h。在此条件下,总生物碱得率为0.312%。[结论]该方法提取效果较好,可用于工业化生产。     

Actions of quinolizidine alkaloids on Periplaneta americana nicotinic acetylcholine receptors

BACKGROUND: Botanical insecticides do not play a major role as crop protectants, but they are beneficial in some applications. The authors investigated the actions of naturally occurring alkaloids on insect nicotinic acetylcholine (ACh) receptors (nAChRs) by evaluating their abilities to inhibit specific binding of [³H]imidacloprid (IMI) to nerve‐cord membranes from Periplaneta americana L. Two alkaloids were also tested for their actions on nAChRs expressed by cockroach neurons using patch‐clamp electrophysiology. RESULTS: Four natural quinolizidine alkaloids (matrine, sophocarpine, cytisine and aloperine) exhibited more than 50% inhibition of [³H]IMI binding at 10 µM , although other compounds were found to have no or low inhibitory activity. The rank order of potency based on concentration–inhibition curves was cytisine > sophocarpine ≥ aloperine ≥ matrine. Patch‐clamp analysis indicated that sophocarpine and aloperine were not agonists of nAChRs expressed in P. americana neurons, yet, at 10 µM , aloperine, but not sophocarpine, suppressed ACh‐induced inward currents significantly. CONCLUSION: Three of the four natural alkaloids tested possess structural moieties that are necessary for interaction with P. americana nAChRs. Aloperine, which possesses a unique structure and showed a distinctive dose–response curve, was found to act as an antagonist. Appropriate modifications of these alkaloids might result in novel insecticidal nAChR ligands. Copyright © 2008 Society of Chemical Industry     

超声法提取骆驼蒿总生物碱的工艺研究

为优化骆驼蒿地上部分总生物碱的提取工艺,在单因素试验的基础上,选取乙醇浓度、提取温度、提取时间3个因素进行正交试验。结果表明:超声提取的影响因素排序为乙醇浓度>提取温度>提取时间;最佳提取条件为10倍量的80%乙醇提取3次,每次50 min,提取温度50℃,总生物碱提取量为1.960 mg.g-1。     

茶树等植物中嘌呤生物碱代谢研究进展

咖啡碱等嘌呤生物碱分布于自然界多种植物中,由于过量摄入咖啡碱会对人体产生副作用,因此对嘌呤碱代谢进行调控,培育低咖啡碱植物品种具有重要的意义。本文综述了嘌呤生物碱在不同属种植物中的分布、生物合成与降解的主要路径及非主要路径、参与嘌呤碱代谢的酶及相应编码基因克隆的研究进展,并对培育低咖啡碱茶树品种中存在的问题与今后的努力方向进行了讨论和展望。