[Identification of Chinese drugs by fluorescence spectrum].

Cortex Fraxini, Radix et Rhizoma Rhei, Semen Astragali Complanati, Semen Lini, Bulbus Fritillariae Cirrhosae, Bulbus Fritillariae Thunbergii and their confused medicinal materials have been identified by the fluorescence spectrum. This is a referential method for the identification of Chinese drugs.

[312 cases of gastric and duodenal ulcer bleeding treated with 3 kinds of alcoholic extract rhubarb tablets].

The alcoholic extracted tablets of rhubarb have been studied medically in this hospital for 10 years. They were divided into three groups, namely, Rheum officinale Baill, Rheum palmatum L, and Rheum tanguticum Maxim ex Balf. By using double-blind measurement of effect, the efficiencies of the groups appeared to be 90.7%, 93.7%, and 92.8% respectively. The time taken for the stool occult blood changing from positive into negative was 57.1, 53.4, and 56 hours respectively (P greater than 0.05). The medical difference is not significant. This shows that they are efficient in curing the upper digestive tract bleeding.

[Extra-weak chemiluminescence of drugs. X. Extra-weak chemiluminescence quenching component of rhubarb].

Active components contained in rhubarb (Rhei Rhizoma) that show a quenching effect of extra-week chemiluminescence (CL) arising from Maillard reaction, had been studied. As the result of fractionation and purification of rhubarb, CL quenching activity was found to exist mainly in the fraction of quinone derivatives as emodin, aloe-emodin or rhein. The authentic samples of these quinones showed high CL quenching activities.

Rapid and simple determination of sennoside A and B in rhei rhizoma by ion-pair high-performance liquid chromatography.

A simple and precise ion-pair high-performance liquid chromatographic method was developed for the determination of sennoside A and B in Rhei Rhizoma. A reversed-phase chromatographic system consisting of a chemically bonded ODS silica gel column with an acetate buffer (pH 5.0)-acetonitrile (68:32), containing 5 mM tetra-n-heptylammonium bromide, as the mobile phase was used. Sennoside A and B in this crude drug were separated and determined within 20 min after direct injection of the solution extracted with 70% methanol. The results for various samples are presented.

Anti-Bacteroides fragilis substance from rhubarb.

Extracts of 178 Chinese herbs were screened for their antibacterial activity against Bacteroides fragilis a major anaerobic microorganism in the intestinal flora of humans. Only rhubarb root (Rheum officinale) was found to have significant activity and the purified active substance was identified as rhein.

Ethnopharmacologic study of Chinese rhubarb.

This paper deals with an interdisciplinary study covering historic, botanical, phytochemical, pharmacological and clinical aspects of rhubarb and related species, to lay stress on the correlation between plant phylogeny, chemical constituents and purgative activity. It was found that the official rhubarbs were exclusively restricted in the Sect. Palmata, e.g. Rheum palmatum, R. palmatum var. tanguticum, R. officinale; the following criteria may serve as their standard, viz., the presence of sennoside derivatives and rhein, the occurrence of the reduced form of rhein and aloe-emodin, the leaves with any kind of palmate incision. Comprehensive multivariate analyses showed that there is a very close relationship between the leaf incision, existence of sennosides or rhein and purgative activity.