The effects of storage on the biological activity of medicinal plants from Nepal

The in vitro biological activity of 19 medicinal plants from Nepal was re-assessed after 6 years of storage. Methanol extracts from the plants were assayed for activity against six strains of bacteria and three strains of fungi. The extracts were tested with and without exposure to UV light in order to identify photoactivity. Out of the 19 plants tested, three lost all activity, six retained all activity, and ten had partial activity. The results will be of interest to traditional healers in Nepal, and may impact the sustainable harvesting of these medicinal plants.