Abstract
We proposed pharmacognostical studies in the prime of molecular biology, citing the systematic studies of Panax drugs and Curcuma drugs. Each study was composed of three approaches, phylogenetic analysis of plants based on nuclear 18S rRNA and chloroplast trnK gene sequences, molecular authentication of herbal drugs, and quality evaluation on bioactive chemical constituents or pharmacological effect. Parsimony analysis of the combined trnK-18S rRNA gene sequence data yielded a well-resolved phylogeny within genus Panax. Based on species-specific sequences of the 2 genes, all the Panax drugs could be identified, furthermore, multiplex amplification refractory mutation system assay was developed for the authentication of 5 important drugs. Quantitative analysis on 11 saponins revealed that each taxon possessed its own characteristic pattern. The trnK/18S rRNA gene sequences could be used not only for an ultimate authentication but also for a speculation of the chemical constituent pattern that affects pharmacological effects. By the same molecular analysis as genus Panax, the potential method for identification of Chinese and Japanese Curcuma species was developed, making it possible to identify Curcuma drugs unambiguously. Using 5 drugs, we examined the effects on vasomotion in rat aortic rings as one index against "Oketsu." All methanol extracts exhibited intense NO-independent relaxation effects. All water extracts showed relaxation effects as the sum of the methanol-soluble compounds-induced relaxation and polysaccharides-induced contraction. Only the water extract of C. zedoaria showed NO-dependent relaxation besides NO-independent relaxation which is common to the other drugs, suggesting the drug derived from C. zedoaria has the potential to cure Oketsu with its various acting points. Such a series of studies will become necessary for standardization of herbal drugs and for their efficient uses.
