Antibacterial and larvicidal activities of Sri Lankan endemic plant, Vateria copallifera

Abstract

Crude acetone extracts of leaf, bark, pericarp and seeds of Sri Lankan endemic plant, Vateria copallifera were evaluated for antibacterial and larvicidal activities against ten clinically important pathogenic microorganisms and 3rd instar mosquito larvae of Culex quinquefasciatus and Aedes aegypti. The highest antibacterial activity with zone of inhibition 19.66 ± 0.65 mm was reported from the seeds against Methicilin resistant staphylococcus aureus (MRSA) as evident from minimum inhibitory concentration (MIC) > 0.01526 mg/ml and minimum bactericidal concentration (MBC) > 0.125 mg/ml. The lowest antibacterial activity was reported from the pericarp against Methicilin resistant staphylococcus aureus with MIC > 0.125 mg/ml and MBC > 4 mg/ml. Seed extract which reported the highest antibacterial activity was subjected to bioassay guided fractionation and obtained five fractions. (F1, F2, F3, F4, F5). From five fractions of seed extract, F2 reported the highest antibacterial activity. Commercially available antibiotic discs sulphamethoxazole trimethoprim (25 μg), ampicilin (10 μg), erythromycin (15 μg) were used as positive controls. absolute ethanol was the negative control with zone of inhibition 0 ± 0. Larvicidal activity was reported only from seed extract with Lc50 and Lc90 values 465.3mg/ml, 915.8mg.ml for Culex quinquefasciatus and 661.3mg/ml and 1105.9mg/ml for Aedes aegypti respectively.