In Vitro Antioxidant and Anti-Mycobacterial Activities of Roselle (Hibiscus sabdariffa L.) Calyx Extract against Clinical Isolate of Multidrug Resistant Mycobacterium tuberculosis

Hibiscus sabdariffa L. or roselle calyx has been known to have biological activities including antioxidant and antibacterial. In this research, we examine the antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) as scavenging agent and the anti-mycobacterial activity towards clinical isolate of multidrug-resistant Mycobacterium tuberculosis (MDR-TB). Roselle calyces were dried and extracted through infusion methods using distilled water, and maceration methods using 50% ethanol, within the ratio of sample (1): solvent (10), followed by spray-drying using maltodextrin as diluting agent. The total phenolic content (TPC) was analyzed using Folin-Ciocalteu method calculated as gallic acid equivalent (GAE), antioxidant activity was analyzed using DPPH method, and anti-mycobacterial activity was assay using Microscopic Observation Drug Susceptibility (MODS) method. As the results, TPC of infusion extract and ethanolic extract were 17.70+0.7 mg GAE/g and 13.15+0.3 mg GAE/g, respectively and IC50 toward DPPH were 0.88 mg/ml for infusion extract and 3.78 mg/ml for ethanolic extract, respectively. Anti-mycobacterial activity of both extracts expressed as Minimum Inhibitory Concentration (MIC) were 10 mg/ml toward clinical isolate of MDR-TB.