Evaluation of Indonesian medicinal plants for their anti-mycobacterial activity by resazurin reduction assay

Abstract

Sari M, Kusharyoto W. 2016. Evaluation of Indonesian medicinal plants for their anti-mycobacterial activity by resazurin reduction assay. Pros Sem Nas Masy Biodiv Indon 2: 138-142. Tuberculosis (TB) is one of the most important infectious diseases caused by a single pathogen bacteria. Tuberculosis infects both healthy and immunocompromised individuals. Natural products derived from microbes and medicinal plants were an important source of TB therapeutics. The microplate resazurin assay (MRA) is commonly used to evaluate natural products and synthetic compounds for anti-mycobacterial activity. This research used MRA method and aimed to evaluate the anti-mycobacterial activity of phytochemical extracts to Mycobacterium smegmatis and M. bovis BCG and compared them to the anti-mycobacterial drug of Rifampicin. MRA was optimized by utilizing 2% DMSO solvent and an indicator solution of 62.5 μg/mL resazurin in 5% tween 80 for 96 hours incubation. The methanolic phytochemical extracts were obtained from various Indonesian medicinal plants that been known empirically to have anti-mycobacterial activity, including Baeckea frutescens (Myrtaceae), Caesalpinia sappan (Fabaceae), Centella asiatica (Apiaceae), Ficus deltoidea (Moraceae), Merremia mammosa (Convolvulaceae), Pluchea indica (Asteraceae), Sida rhombifolia (Malvaceae), Tinospora crispa (Menispermaceae), Usnea barbata (Parmeliaceae) and Zingiber aromaticum (Zingiberaceae). The results showed that S. rhombifolia and L. lavandufolia extracts have a potential as an antimycobacterial activity against M. smegmatis, also F. deltoidea and B. frustecens extracts have an activity against M. bovis, and Z. aromaticum extract has a potency as anti-mycobacterium for both of them (M. smegmatis - M. bovis). The application of MRA using M. smegmatis or M. bovis BCG as anti-mycobacterial targets had several advantages such as low-cost, rapid testing and safe screening for anti-mycobacterial activity in a high-throughput format.