ANTIBACTERIAL POTENTIAL OF PARTIALLY PURIFIED FRACTIONS OF LEAF EXTRACT OF SPONDIAS MOMBIN

This study was conducted to investigate the antibacterial activity and rate of kill of the various partially purified fractions of Spondias mombin’s leaf extract on selected pathogenic bacteria. Fresh leaves of Spondias mombin were air-dried and then ground into fine powder. The powdered leaves of Spondias mombin were extracted using ethanol-water in the ratio 1:1 (v/v). The crude extract was fractionated by partial purification using various solvents such as n-hexane, chloroform, ethyl-acetate, and n-butanol. The fractions were concentrated in vacuo and lyophilized. Afterward, the different fractions were tested for antibacterial activities against selected pathogenic bacteria using the agar well diffusion method. The minimum inhibitory and minimum bactericidal concentrations were determined using the standard microbiological method. The rate of kill of the test isolates by the active fractions (n-butanol, ethyl acetate, and n-hexane fractions) was also determined. The zones of inhibition shown by the active fractions at 15 mg/mL on the isolates ranged between 11.7 mm and 15.7 mm while the minimum inhibitory and minimum bactericidal concentrations of the active fractions on the bacterial isolates were 15.00 mg/mL. The killing/death rate of the active fractions was observed to increase with increased concentration of the active fractions and increased contact time. This study established that the fractions of Spondias mombin leaf extract investigated had considerable antibacterial activity and were bactericidal in action with a broad spectrum of activity against both Gram-negative and Gram-positive bacteria used in this study.