硅钨酸质量法测定延胡索总生物碱质量分数

建立延胡索总生物碱质量分数检测方法.运用硅钨酸质量法,将延胡索总生物碱中生物碱物质转化为可以准确称量的形式,计算延胡索总生物碱质量分数.三批样品质量分数平均值为57.12%,符合中药五类新药技术研究要求.所建立的方法操作简便、准确、可靠,适用于延胡索总生物碱的质量控制.     

You are what you eat: native versus exotic Crotalaria species (Fabaceae) as host plants of the Ornate Bella Moth,Utetheisa ornatrix (Lepidoptera: Erebidae: Arctiinae)

Crotalaria plants and Utetheisa ornatrix are closely linked to each other: the larvae destroy the seeds, while the moth depends on hostplants for alkaloids. To better understand the ongoing co-evolution, the present study examines how native hostplants compare to exotic ones. Leaf-feeding on Crotalaria pumila, C. rotundifolia, and C. incana, native to the moth’s range, led to faster larval development than on the exotic C. lanceolata, C. spectabilis, and C. pallida. Seed-feeding on all species of Crotalaria led to accelerated larval development and a resultant larger adult moth, and correlates with a higher nitrogen content in the plant tissues. These results add a novel dimension to the previous studies of reproductive biology of this model organism. In controlled settings, mature larvae showed preference for leaves of C. spectabilis over those of other species, perhaps due to the higher alkaloid content. Differences in morphology and phenology of Crotalaria determine the ecology of U. ornatrix populations in Florida. The introduction of novel hostplants, on which U. ornatrix can have a significant negative effect and which are of concern to humans as invasive toxic weeds, has greatly expanded the niche occupied by this moth. Possible co-evolution of Utetheisa sensu lato and plant defences in the genus Crotalaria is discussed.     

金钗石斛中生物碱提取的动力学分析

将金钗石斛用氨水浸润后,以氯仿为溶剂,在不同液固比、不同提取时间和不同提取温度下提取生物碱,以Fick第二定律为依据,以提取生物碱质量浓度为检测指标,求解提取动力学的表观传质速率方程、速率常数k、相对萃余率和表观活化能Ea等数值,建立金钗石斛生物碱提取过程的动力学模型.结果显示:在液固比为60,提取温度为60℃,提取时间为90 min时,所提取的生物碱质量浓度较高,金钗石斛生物碱提取过程的动力学基本符合一级动力学方程,在不同影响因素下,表观传质速率ln[C_∞/(C_∞-C_0)]、相对萃余率与时间t均有比较好的线性关系,提取动力学方程的活化能Ea为55.075 k J/mol.由此知金钗石斛生物碱提取过程的关键控制步骤为溶质的内扩散步骤.     

An important functional group,benzo[1,3]dioxole,of alkaloids induces the formation of the human telomeric DNA G-quadruplex

Over the past few decades, numerous molecules have been discovered or designed to interact efficiently and selectively with a peculiar DNA structure named G-quadruplex. Some of these molecules have been developed as anticancer agents. To aid the design of anticancer agents, the ability of alkaloids possessing Protoberberine and Benzophenanthridine groups to induce the formation of G-quadruplexes were studied using CD spectroscopy. By careful examination of their structures, we found that a benzo[1,3]dioxole group plays an important role in influencing their inductive properties. The more functional groups the alkaloids have, the stronger their G-quadruplex inductive ability.     

从苦豆子中分离纯化苦参碱和槐定碱的工艺研究

运用稀酸水法从苦豆子种子中提取生物碱,最佳提取条件为料液比1∶30,pH 1.5,提取时间5h。使用大孔树脂吸附法对提取的生物碱进行纯化,考察了SP850、SP825、SP700、SP207、AB-8等5种树脂的吸附效果,其中SP850型树脂吸附量和解析量均最大,分别为27.4mg/mL和20.4mg/mL。测定了体积分数为50%、60%、70%的乙醇洗脱效果,确定了60%乙醇为最佳洗脱浓度,洗脱体积为6倍柱体积。经氯仿萃取和旋转蒸发,得到纯度达83.5%的生物碱粗产品。运用硅胶柱层析技术从生物碱粗品中分离生物碱单体,考察了氯仿-甲醇-氨水系统,正己烷-乙醇-氨水系统,丙酮-甲醇-氨水系统在硅胶薄层色谱上对生物碱的分离效果,确定以V_正己烷∶V_乙醇∶V_氨水=8∶2∶0.1作为流动相。收集洗脱液,经过结晶和重结晶,得到苦参碱和槐定碱晶体。经检测,苦参碱纯度为98.3%,槐定碱纯度达96.8%。     

蝙蝠葛酚性碱对胃癌细胞SGC-7901 COX-2表达的影响

为探讨蝙蝠葛酚性碱(PAMD)抗胃癌的作用机理,通过实时定量PCR观察PAMD对胃癌细胞株SGC-7901 COX-2 mRNA表达的影响.结果表明,PAMD各剂量组均能下调COX-2 mRNA的表达,其中PAMD(20)剂量组下调COX-2的作用有统计学差异,且优于阳性对照组.PAMD抗胃癌的作用机理可能与其抑制COX-2基因表达有关.     

不同采收期金钗石斛总生物碱及多糖质量分数的变化

采用紫外-可见分光光度法测定不同采收期金钗石斛药材中总生物碱和总多糖的质量分数,并对其总生物碱和多糖成分的质量分数变化进行比较.结果表明:在每年的3,9,10,11,12月份采收的金钗石斛中总生物碱的质量分数较高;总多糖的质量分数在每年的10,11月份相对较高.     

二萜类生物碱的药理作用及构效关系研究概况

二萜类生物碱是一类生物活性较强的植物成分，具有多种药理作用，但其往往又表现出不同程度的毒性，它们的结构和活性之间有着密切的关系，总结了二萜类生物碱的药理作用，并概述了其构效关系。     

组培川贝母质量标准研究

参照2010年版《中国药典》相关方法,建立组培川贝母总灰分、酸不溶性灰分、浸出物、薄层色谱等项目的检查方法并规定限度,采用紫外分光光度法建立组培川贝母的总生物碱含量测定方法并规定限度,以此对组培川贝母进行质量标准研究.结果表明：组培川贝母的总灰分不应超过2%,酸不溶性灰分不应超过1%,浸出物不得少于20%,总生物碱含量应在0.2%-0.3%之间;本研究建立的质量标准可以控制组培川贝母的质量.     

石蒜科植物中生物碱的药理作用研究

阐述了石蒜科(Amaryllidaceae)植物的主要药用种属和其所含生物碱的多种药理作用.石蒜科植物含有多种独特的生物活性或药理活性的生物碱类化合物,最新研究表明其具有抗肿瘤、抗白血病、抗菌抗病毒以及对心血管系统、中枢神经系统的作用等药理活性.通过对其生物碱药理作用的归纳,为石蒜科植物进一步的开发利用提供参考.