Evaluation of Antibacterial Properties of Leaves and Barks of Rhizophora stylosa against Gram-Positive and Gram- Negative Organisms

Abstract

The number of multi-drug resistant microbial strains and the appearance of strains with reduced susceptibility to antibiotics are continuously increasing and it has been attributed to indiscriminate use of broad spectrum antibiotics. It is common sense that the scarcely explored extensive Malaysian biodiversity would yield countless opportunities to find plant species potentially secreting metabolites, exhibiting antimicrobial activity, among other medicinal properties. In this study leaves and barks of Rhizophora stylosa were collected and extracted using various organic solvents such as petroleum ether, chloroform and methanol. These crude extracts were further evaluated for antimicrobial properties by different methods against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aueroginosa. The bark extracts were more potent than leaf extracts of R. stylosa. The chloroform extracts were found to have the highest antimicrobial activity with an MIC of 0.1 mg/ml and MBC of 6.3 mg/ml.

Keywords

• leaves
• bark
• antimicrobial properties