Antimicrobial activity of South African Podocarpus species

Ethnopharmacological relevance: Several species of Podocarpus (Podocarpaceae) are utilized in treating ailments across the world. In Africa, four species are used traditionally in both animal and human health. Aim of the study: To investigate the antimicrobial activity of Podocarpus species against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Candida albicans. Materials and methods: Six solvents of varying polarity were used for extraction. Antibacterial activity was assessed using the microdilution bioassay and for antifungal activity, the microdilution bioassay and (M27-P) broth dilution were used. Results: All species exhibited antimicrobial activity with MIC values of less than 1 mg/ml. Inhibition against Gram-positive bacteria was stronger with an MIC value of 98 mu g/ml while for Gram-negative bacteria, the highest inhibition was against Klebsiella pneumoniae with an MIC value of 0.33 mg/ml. All species exhibited strong antifungal activity with the best MIC being 30 mu g/ml after 48 h. Conclusions: All four species exhibited strong inhibition against all tested microbials, based on Aligiannis et al. [Aligiannis, N., Kalpotzakis, E., Mitaku, S., Chinou, I.B., 2001. Composition and antimicrobial activity of the essential oils of two Origanum species. journal of Agricultural and Food Chemistry 40, 4168-4170] classification they can be classified as strong inhibitors. (C) 2008 Elsevier Ireland Ltd. All rights reserved.