Altitudinal variation in pharmacologically active compounds of wild and cultivated populations of Epimedium elatum

Epimedium is a well known genus of Chinese pharmacopoeia, possessing various medicinal properties such as aphrodisiac, antioxidant, immunomodulatory, vasodilatory, hepatoprotective, cardioprotective, antidepressant, anticancerous and antiosteoporosis activities. The active principle has been found to be its flavonoid glycosides, especially Icariin and Icariside-II. In the present study, Epimedium elatum, the only species of this genus growing in Indian subcontinent and endemic to Kashmir Himalayas, has been studied for its active principle content at different habitats. The plants were collected from wild populations (W-I W-II &W-III) growing at three different sites of different altitudes and cultivated at low altitudes of Central Kashmir. After two years, the plants from wild populations as well as cultivated populations were collected, shade dried, grinded and prepared for HPLC analysis. The results showed that the content of active principles in leaves vary significantly between plants growing at different habitats. The Icariin and Icariside-II yield (per plant) of wild populations significantly increased with a decrease in altitude of habitat. Cultivated population growing at higher altitude had significantly more yield than all other populations, except the W-III. The content of active principles as a percentage of leaf dry mass increased with increase in altitude. However, the harvest index of wild populations showed a decreasing trend with increasing altitude. The content of active principles as a percentage of dry mass of whole plant was comparable in all the habitats, including the cultivated populations. The present study suggests that Epimedium plants cultivated at lower altitudes are equally or more productive in terms of Icariin and Icariside-II content than that of wild plants growing at higher altitudes.