4.16. Antimycobacterial Activity
In a study carried out to determine the antimycobacterial activity of several medicinal plants, including RZZ, used as self-medication by AIDS patients in Thailand, 38 crude chloroform, methanol and water extracts of 12 plants were tested against Mycobacterium tuberculosis using the microplate Alamar blue assay [56]. All plants’ extracts tested at the initial concentration of 1000 μg/mL inhibited the growth of M. tuberculosis H37Ra. Active extracts were retested at lower concentrations to determine their MICs. Of all RZZ extracts, only the CEZZ and MEZZ were found to produce MICs at 125 and 1000 μg/mL, respectively. However, of all plants tested only the chloroform extract of A. galanga and P. chaba was considered to have a strong antimycobacterial activity indicated by their MIC value that was