Evaluation of the Antifungal properties of Picralima Nitida seed extracts

Abstract

The antifungal properties of Picralima nitida seed extract used in this study were determined by percentage growth inhibition (GI) and minimum inhibitory concentration (MIC). Methanol, ethanol and hot water were used for the extraction. Methanol extract exhibited more antifungal action than ethanol and water extracts although ethanol compared favorably with methanol. The antifungal action of the extracts was in the order of methanol > ethanol > hot water. Complete inhibition of growth (100%) was achieved on Aspergillus niger, A. oryzae and Rhizopus stolonifer at 250 mg/ml concentration of Picralima nitida seed methanol and ethanol extracts. Complete inhibition of growth was observed on A. niger and R. stolonifer with methanol extract and R. stolonifer with ethanol extract at 125 mg/ml concentration. Hot water extract achieved 50, 26.67 and 70% inhibition against A. niger, A. oryzae and R. stolonifer, respectively. As concentration reduced, percentage inhibition reduced up to minimum inhibition concentration. Phytochemical screening of Picralima nitida seed extracts showed the presence of hydrogen cyanide (200 ppm), tannin, alkaloid, steroid and oxalate (3.96 ppm) as well as flavonoid and carbohydrate. Since these extracts at appropriate doses inhibited and eventually killed the test fungi, they could successfully be used to control plant pathogens and in food preservation.

Keywords: Picralima nitida seed, growth inhibition, fungus, plant pathogens, food preservation

International Journal of Natural and Applied Sciences, 7(1): 41 - 46, 2011