薄层扫描法测定垂阴茶糖浆中岩白菜素的含量

目的:建立垂阴茶糖浆岩白菜素的测定方法,方法:λs=275 nm,λR=320nm,用薄层色谱法测定岩白菜素的含量.结果:岩白菜素在0.505～3.030μg范围内线性关系良好(r=0.999 9),平均回收率为96.52%.RSD=0.44%.结论:该法灵敏度高,重现性好,可用于该制剂中岩白菜素的含量测定及质量控制.     

Chlorination diversifies Cimicifuga racemosa triterpene glycosides

Extracts from the roots and rhizomes of black cohosh (Cimicifuga racemosa) are widely used as dietary supplements to alleviate menopausal symptoms. State-of-the-art quality control measures involve phytochemical fingerprinting of the triterpene glycosides for species identification and chemical standardization by HPLC. In the course of developing materials and methods for standardization procedures, the major C. racemosa triterpene glycoside (1) was isolated and initially thought to be cimicifugoside (2). Detailed HR-LC-MS and 1D and 2D NMR analysis of 1 and 2 unambiguously revealed that 1 is the chlorine-containing derivative of 2, namely, 25-chlorodeoxycimigenol-3-O-beta-d-xyloside. Accordingly, HPLC profiles of black cohosh preparations require revision of the assignments of the chlorinated (1) and nonchlorinated (2) pair. Besides explaining the substantial shift in polarity (DeltatR[RP-18] ca. 20 min), 25-deoxychlorination opens a new pathway of structural diversification in triterpene glycoside chemistry. As chemical conversion of 2 into 1 could be demonstrated, deoxychlorination may be interpreted as artifact formation. Simultaneously, however, it is a potentially significant pathway for the gastric in vivo conversion ("nature's prodrug") of the relatively polar triterpene glycosides into significantly less polar chlorinated derivatives with altered pharmacological properties.     

青蒿挥发油成分的GC-MS分析与化学计量学解析法

目的:分析青蒿挥发油的化学成分.方法:用水蒸气蒸馏法从青蒿中提取挥发油成分,采用气相色谱-质谱(GC-MS)联用技术,结合化学计量学解析法(CRM)对重叠色谱峰进行分辨解析,并利用程序升温保留指数辅助定性.结果:共分辨出73个色谱峰,鉴定了其中66个组分,占青蒿挥发油总含量的95.25%,其主要化学成分为:丁子香烯、丁子香烯环氧化物、稚槛蓝(树)油烯、α-甜没药萜醇等.结论:使用CRM解析色谱峰,比单独使用GC-MS法能更真实、全面地反映其挥发油化学成分.     

诸子蜂起 百家争鸣(二)——英国中医药的现状与展望

中医药面临着"诸子蜂起,百家争鸣"的国际医药保健时代,处于有机会又有曲折的局面.故从1)中医药在国外的发展.2)中医药在英国的现状.3)英国推动中医教育的经验.4)英国偶尔发生的中医事故影响中医界整体形象.5)英国中医的立法过程与国际影响.6)建立中医药企业文化和品牌标准--英国的经验.7)中医药发展展望.8)中医药的宣传和外交等方面论述.指出在"诸子蜂起,百家争鸣"的新"全球医学"时代,中医界人士需团结一致,既往开来,为把中医真正纳入世界主流医学,并能恩泽于全人类而全心全力、努力不懈!     

Mechanisms of the dilator action of the Erigerontis Herba on rat aorta

Ethnopharmacological relevance

Erigerontis Herba is widely used as a traditional Chinese medicine and is commonly used for neuroprotection and vascular protection.

Aim of study

In this study, the vasodilator effects of Erigerontis Herba (DZXX) were investigated using rat isolated aorta rings.

Material and method

The involvement of endothelium in the vasorelaxation was studied by comparing response of endothelium-intact and endothelium-denuded aorta rings which precontracted with U46619. The involvement of K⁺ channels was studied by pretreatment of the aorta rings with various K⁺ channel inhibitors. The involvement of Ca²⁺ channel was studied by incubating aorta rings with Ca²⁺-free solution, primed with U46619 prior to elicit contraction by addition of Ca²⁺ solution.

Results

DZXX (0.2–2 mg/ml) induced a concentration-dependent relaxation on U44619-precontracted aorta rings with EC₅₀ of 0.354±0.036 mg/ml. Removal of endothelium or pretreatment with a BK_Ca inhibitor iberiotoxin, K_IR inhibitor barium chloride or K_v inhibitor 4-aminopyridine produced no effect on the DZXX-induced vasorelaxation. However, pretreatment with a K_ATP inhibitor glibenclamide or a non-selective K⁺ channel inhibitor tetraethylammonium produced significant inhibition on the DZXX-induced vasorelaxation by 29.9% and 21.3%, respectively. Pretreatment with DZXX (0.4, 1.2 and 2 mg/ml) produced a concentration-dependent inhibition on Ca²⁺-induced vasoconstriction.

Conclusions

These results suggest that the vasodilator effect of DZXX was endothelium-independent, mediated by decreasing the influx of Ca²⁺ by calcium channel inhibition and increasing the influx of K⁺ by opening of a K_ATP channel.     

千层塔中三萜成分的研究

前曾报道自千层塔[Huperzia serrata Thunb.(Trev)=Lycopodium serratum Thunb(Trev.)]中分得具有胆碱酯酶抑制活性的新生物碱——石杉碱甲、石杉碱乙、甲基石杉碱乙及已知生物碱8-deoxyserratinine,serratinine,lycodoline及lycoclavine。为进一步阐明该植物的化学成分,我们对其三萜成分进行了研究。从浙江安吉产的千层塔植物中分到六个石松三萜,其中一个为新化合物,经下述方法推定为serratenediol-21-acetate(Ⅰ)。另五     

国产麻黄的形态组织学研究——Ⅱ.西南主产种及其它种

本文报道我国西南产麻黄——丽江麻黄Ephedra likiangensis Florin、匍枝丽江麻黄E.likiangensis f.mairei(Florin)C.Y.Cheng、藏麻黄E.saxatilis Royle ex Florin、山岭麻黄E.gerardiana Wall、垫状山岭麻黄E.gerardiana Var.congesta C.Y.Cheng、矮麻黄E.minuta Florin和异株矮麻黄E.minuta var.dioeca C.Y.Cheng,以及形态组织特征较特殊的宁夏产斑子麻黄E.lepidosperma C.Y.Cheng、新疆产窄膜麻黄E.lomatolepis Schrenk,西藏产西藏中麻黄E.intermedia var.tibetica Stapf的生药形态组织学研究结果。并根据对国产麻黄的生药形态组织学的系统研究结果,分别编写了各种国产麻黄(包括13种3变种1变型)的生药性状和生药显微特征检索表。     

蜜环菌菌丝体化学成分的研究——Ⅴ.蜜环菌辛素和蜜环菌壬素的分离与鉴定

从人工液体发酵培养的蜜环菌[Armillaria mellea(Vahl.ex Fr.)Quel.]菌丝体的石油醚提取物中,经硅胶柱层析,低压柱层析和制备性薄层层析分离得到两个新的原伊鲁烷型倍半萜芳香酸酯类化合物。命名为蜜环菌辛素(armillarilin)和蜜环菌壬素(armillarinia),根据光谱(UV,IR,~1HNMR,~(13)CNMR和MS)分析,推定它们的化学结构分别为Ⅰ和Ⅱ。     

固相法合成心肌兴奋肽及其类似物

用Boc-和Tos-基团分别保护氨基和侧链胍基,以1%交联度聚苯乙烯二苯甲氨基树脂为载体,用DCC固相法合成肽,HF断裂肽树脂键和去除侧链保护基团,粗产物经高效液相层析纯化,合成了心肌兴奋肽Phe-Met-Arg-Phe-NH_2及其类似物Phe-Pro-Arg-Phe-NH_2,并观察了此二种肽对大鼠血压和心率的影响。