New finding of an anti-TB compound in the genus Marsypopetalum (Annonaceae) from a traditional herbal remedy of Laos

Abstract

Ethnopharmacological relevanceThere is widespread use of traditional herbal remedies in the Lao PDR (Laos). It is common practice to treat many diseases with local plants. This research project documented and analysed some of these traditional remedies used to treat symptoms of tuberculosis (TB). Materials and methodsThis research was executed by interviewing healers about plants used traditionally to treat the symptoms of TB. Samples of some of the plants were collected, and extracts of 77 species were submitted to various in vitro assays in order to determine the amount of growth inhibition of virulent Mycobacterium tuberculosis H37Rv (Mtb), as opposed to other microbes and mammalian Vero cells. ResultsInterviews took place with 58 contemporary healers in 5 different provinces about plants currently used, giving a list of 341 plants. Bioassay-guided fractionation was performed on Marsypopetalum modestum (Pierre) B. Xue and R.M.K. Saunders (Annonaceae), leading to the isolation of dipyrithione, an anti-mycobacterial compound isolated for the first time from the genus Marsypopetalum through this research. ConclusionsThis research has helped to increase awareness of Laos’ rich diversity of medicinal plants and will hopefully provide incentive to preserve the undeveloped forested areas that remain, which still hold a wealth of medical information for future discoveries.