Pharmacognosical Studies On Hypericum Spp.

There are more than 400 species in genus Hypericum Linn, in the world, which exhibit a diversity of habit forms ranging from slender herbs to large shrubs, small trees and distribute extensively in Europe, Asia, North of Africa and North of America. There are 55 species and 8 varietas in China, which almost distribute all over the country but mainly in Southwest. Most species of the genus have the effects of clearing away the heat and toxins, restoring menstruation and promoting blood circulation, arresting bleeding and promoting tissue regeneration, relieving swells and alleviating pains. In folk, it is often used to treat irregular menstruation, traumatism and etc.. In recent years Hypericum perforation L. was proved to have the activity of antidepressant and anti-HIV, the genus has aroused the pharmacists' great attention.This dissertation deals with a systematic Pharmacognosical studies on 16 species of Hypericum including survey on the resources, histological identification, physiochemical identification, quality assessing of main medicinal species and their antidepressant activities.On the basis of survey on the resources, the geographical distribution of five species include Hypericum perforatum, Hypericum ascyron, Hypericum sampsonii, Hypericum wightiaum and Hypericum faberi in China had been drawn separately. 21 wild species of this genus had been collected and identified, of which 15 species are pharmaceutical plants.Based on microscopic survey, Hypericum subsessile and Hypericum acmosepalurn were found that their young stem present hexagon wheras others quadrilateral, and their vascular bundles forming quadrilateral but not closed ring. Secretory canals are present generally in the pholem. They are found in the pith of Hypericum ascyron and in the primary cortex of Hypericum lancasteri, which can be a key to the identification of the two species from others.TLC analysis gave a result that similarities and differences in chemical constituents of 21 species in Hypericum exist, it was also presented that most of herbs contains pseudohypericin as well as hypericin and the fluorescent intensity of hypericin or pseudohypericin are far more stronger than that of shrubs, the result means the contents of those two constituents in herbs are more higher than that in shrubs. We can also identify different species by NIRDRS (near infrared diffuse reflectance spectroscopy) and DTA (differential thermal analysis) tests.In order to evaluate the qualities of different species, RP-HPLC method was employed to establish HPLC-Fingerprintings of 11 main pharmaceutical species, and the contents of six active components including rutin, hyperoside, quercetin, hyperforin, hypericin and pseudohypericin were determined. The contents of those components were found higher separately in Hypericum perforation than other species, but the content of hyperforin, which was considered the most posssible antidepressant active component, was found the highest in Hypericum lancasteri among these 11 species.Forced swimming test (FST) and reserpine reversal test (RRT) were used to study the antidepressant activity of 4 species including Hypericum perforatum, Hypericum lancasteri, HZQM and Hypericum faberi, the results showed the ethanol total extracts of these 4 species can reduce the immobile time in FST and antagonize rat falling temperature induced by reserpine in RRT in different extent, of which Hypericum lancasteri and HZQM had better effects than Hypericum perforaturn and Hypericum faberi. different dosage of HZQM were employed in RRT and the result present dose-response-relationship. HZQM exhibit better antidepressant activity than other species, its mechanism will be studied in further experiments.