Rapid Determination of Aristolochic Acids I and II in Some Medicinal Plants by High-Performance Liquid Chromatography

Aristolochic acids (AA) are toxic components of Aristolochia plants which result in diseases of the kidney such as urothelial cancer. It is, therefore, essential to monitor the amount of aristolochic acid in herbal medicines. In this study a reversed-phase high-performance liquid-chromatographic (HPLC) method has been developed for rapid determination of aristolochic acids I and II. Baseline separation was achieved within five minutes by use of an ODS C₁₈ column with methanol–water, 60:40, as mobile phase. Two kinds of aristolochic acid were successfully determined in 31 herbal samples of Aristolochia fangchi Wu and Caulis Aristolochiae Manshuriensis. The results indicated that in most samples the aristolochic acid I content is much higher than that of aristolochic acid II. The two kinds of aristolochic acid were not detected in Aristolochia fangchi from the Guangdong region, so Aristolochia fangchi from this region is recommended for use in herbal remedies.     

Quantification of four active ingredients and fingerprint analysis of Licorice (Glycyrrhiza uralensis Fisch.) after spaceflight by HPLC–DAD

The rhizomes growing from Licorice (Glycyrrhiza uralensis Fisch.) seeds carried by the Chinese recoverable satellite named ??Shen Zhou?? and from the parallel ground-based seeds were selected as the samples. Seeds were flown under the space condition for 18?days. Average radiation dose in the flight recovery module was 0.102?mGy/day and the distance from flight apogee to earth was 350?km and the gravity was 10^?6?g. After returning to earth, the seeds carried by the satellite and the parallel ground control were cultivated to maturity under the same condition. In this paper, fingerprint was obtained and contents of the four main ingredients of the samples were investigated on a high performance liquid chromatography with diode-array detection. The differentiation between the 12 samples induced by cosmic factors was observed. Contents of the detected four components of space flight group were much higher than that of the control group. Areas of the 26 common peaks of the 12 samples were analyzed by principal component analysis and three components were extracted. The results demonstrated that extraterrestrial environment could affect the amount of its secondary metabolites. This report provided the scientific data for spaceflight breeding of a medicinal plant and indicated that extraterrestrial orbit is a possible way in accelerating the rate of breeding and select eximious germplasm resources.     

Total synthesis and biological evaluation of dracaenins A and B

The first total synthesis of dracaenins A and B is achieved in four steps. The synthesis features the convergent coupling of three readily available fragments with minimized use of protecting groups. The chemical synthesis enables the discovery of their activity in stimulating platelet aggregation, and thus, sheds light on the possible origin of the hemostatic effect of dragon’s blood.     

Two new glycosides from the genus of Cassia

Two new glycosides were isolated and characterized by spectral analysis from the seeds of Cassia obtusifolia and the leaves of Cassia angustifolia.The structure was elucidated as 1-hydroxyl-2-acetyl-3,8-dimethoxynaphthalene-6-O-β-D-apiofuranosyl- (1→2)-β-D-glucopyranoside and 2-acetyl-3-methyl-8-methoxyl-1,4-naphthoquinone-6-O-β-D-glucopyranoside.     

Two new triterpenes from the seeds of Trichosanthes cucumeroides

Two new triterpenes named 7-oxodihydrokarounitriol (1) and 7,11-dioxodihydrokarounidiol (2), and one known triterpene, 7-oxodihydrokarounidiol (3), were isolated from the unsaponifiable matter of the seeds of Trichosanthes cucumeroides. The structures of 1 and 2 were elucidated as (3alpha, 11beta, 13alpha, 14beta, 20alpha)-3,11,29-trihydroxy-13-methyl-26-norolean-8-ene-7-one, and (3alpha,13alpha,14beta,20alpha)-3,29-dihydroxy-13-methyl-26-norolean-8-ene-7,11-dione on the basis of extensive NMR (1H, 13C, 1H-1H COSY, DEPT, HMQC, HMBC and NOESY) and MS studies.     

A new trimeric furanocoumarin from Heracleum rapula

A new trimeric linear-type furanocoumarin,rapultririn A(1),was isolated from the underground part ofHeracleum rapula.The structure of this new compound was elucidated by NMR,MS spectroscopic methods.     

Estimation of the antioxidant activities of flavonoids from their oxidation potentials.

A simple electrochemical method for estimating the antioxidant activity (AA) of flavonoids has been developed. The proposed method is based on a measurement of the half-wave potential (E1/2) of the first oxidation wave of flavonoids by using flow-through column electrolysis. At the same time, the lipid peroxidation (LPO) inhibiting effects of these flavonoids were determined. A quantitative structure-activity relationship was obtained to describe the AA of flavonoids: IC50(microM) = 30.36 + 151.50 E1/2 (V) -12.63 log P (r = 0.852), where IC50 represents the concentration for 50% inhibition of LPO, and P represents the octanol/water partition coefficient. This method is expected to be useful for the quick screening of flavonoid antioxidants, and evaluating the AA of flavonoid-containing foods and medicinal plants.     

基于化学荧光测定的板蓝根抗病毒效价检测方法的建立

荧光测定法在化学分析和生物检测中已广泛应用,将该法引用到中药的生物效价检测中则是一种新的尝试。而生物效价检测与药效直接相关联,是研究中药质量控制与品质评价方法的新趋势。为了建立与抗病毒药效相关的板蓝根质量控制和评价方法,采用化学荧光测定法考察了板蓝根提取物对流感病毒神经氨酸酶(NA)的体外抑制活性,分析了其药理作用的量效曲线变化趋势和作用规律。在此基础上并根据生物检定的统计学原理,以“质反应平行线”法设计和优化检测条件,建立了板蓝根抗病毒生物效价荧光检测方法。实际测试结果能够灵敏、定量表征样品间的品质差异,方法的可靠性和可重复性较好。以此作为板蓝根质量生物控制和评价方法,能够体现中药药效特点。