Antimicrobial activity of Hermannia incana

Abstract

Hermannia incana Cav. (Sterculiaceae) is a prostrate herb used to treat stomachache and diarrhea, and as an emetic by the people of Eastern Cape Province, South Africa. Acetone, methanol, and water extracts from the leaves and roots of the plant were investigated for antibacterial and antimycotic activities. The methanol extracts of the plant showed appreciable activity against Gram-positive and Gram-negative bacteria at concentrations ranging from 0.5 to 7 mg/mL. The acetone and water extracts of both the leaves and the roots showed moderate activity against Gram-positive bacteria and less activity against Gram-negative bacteria. All the extracts inhibited the growth of the fungi Aspergillus flavus, Aspergillus niger, and Mucor hiemalis with growth inhibition based on MIC ranging from 54% to 96% at 0.1- 10 mg/mL. None of the extracts suppressed the growth of Candida albicans at the maximum concentration (10 mg/mL) tested. This study has pointed to the potential application of Hermannia incana as a bacteriocide and fungicide.