Antimicrobial, anti-inflammatory and genotoxicity activity of Alepidea amatymbica and Alepidea natalensis (Apiaceae)

Antibacterial, antifungal, anti-inflammatory and genotoxicity tests were carried out on petroleum ether (PE), dichloromethane (DCM), 80% ethanol (EtOH) and water extracts of two Alepidea species, A. natalensis Wood & Evans and A. amatymbica Eckl. & Zeyh. Water extracts of A. natalensis rhizomes exhibited high activity against four bacterial strains; Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus with MIC values of 0.78 mg/ml. High activity was also observed in the PE and DCM leaf extract of the same plant against the Gram-positive bacteria. The PE and DCM extracts of A. amatymbica rhizomes exhibited the best activity (MIC values of 0.39 mg/ml) against B. subtilis. The rest of the extracts showed low activity (MIC values > 1 mg/ml). All the extracts showed activity against Candida albicans, with A. natalensis leaf extracts exhibiting the highest antifungal activity with MIC values of 0.88, 0.2 and 0.78 mg/ml for PE, DCM and EtOH respectively. The PE and DCM extracts had high COX-1 activity with percentage inhibitions above 70%. Ethanol extracts had inhibition less than 40% for both A. natalensis and A. amatymbica. All the PE extracts showed higher COX-2 inhibitory activity than for COX-1. There were no significant differences in the activity exhibited by DCM extracts in COX-1 and COX-2. PE and DCM extracts both had percentage inhibitions above 70% for both COX-1 and COX-2 inhibition. The Ames test for genotoxicity revealed that none of the plant extracts significantly increased the number of His+ revertants with respect to the level observed in the negative control plates.