Antibacterial and cytotoxic evaluation of sequential extract of Moringa oleifera leaves

Abstract

Moringa Oleifera is an interesting plant used in Asian traditional medicine. In this study, in vitro antibacterial and cytotoxic evaluation of sequential extracts (aqueous, ethanol, and chloroform) of Moringa Oleifera was carried out. The antibacterial analysis was estimated with minimum inhibitory concentration (MIC) by micro dilution of Moringa Oleifera against common poultry pathogens Clostridium perfringens type A and Escherichia coli, while cytotoxic evaluation was estimated by the reduction in cell viability due to apoptosis or necrosis by metabolic events in the presence and absence of crude extracts or tested component. The aqueous extract shows the highest percentage yield (45/50gm) succeeded by ethanol extract (5.5gm/50gm) and chloroform extract (0.2gm/50gm). In our study, the zone of inhibition of sequential extracts of Moringa Oleifera against Haemophilus species are highest for chloroform (17mm), intermediate for ethanol (13mm), and lowest for aqueous extract (12.3mm). For chloroform extract the CSP was calculated at 10 different concentrations, 2000 µg/ml, 1000µg/ml, 500µg/ml, 250µg/ml, 125µg/ml, 62.5µg/ml, 31.25µg/ml, 15.63µg/ml, 7.81µg/ml and 3.91µg/ml .The results for cell survival percentage (CSP) in the present research are 26%, 46%, 58%, 55%, 60%, 63%, 62%, 59%, 68% and 82% respectively. The CSP results of chloroform extract indicated that it is toxic for cells at ≥1000µg/ml. At 1000µg/ml concentration CSP was 46% which is > 50% and therefore it is cytotoxic. At higher concentrations, chloroform is more cytotoxic than hexane because at > 1000µg/ml the cell survival percentage was recorded to be < 50%. For ethanol extract CSP was calculated at 10 concentrations, 6000µg/ml, 3000µg/ml, 1500µg/ml, 750µg/ml, 375µg/ml, 187.5µg/ml, 93.75µg/ml, 46.85µg/ml, 23.43µg/ml and 11.71µg/ml. The CSP values are 18%, 48%, 60%, 58%, 69%, 56%, 59%, 74%, 57% and 78% respectively which indicate that at concentrations ≥3000µg/ml the chloroform extract is toxic for cells. At a concentration less than 3000µg/ml, the CSP is more than 50%. So, as compared to hexane and chloroform, ethanol extract is less toxic at higher concentrations. Cytotoxicity of aqueous extract was calculated at 10 concentrations, 5000µg/ml, 2500µg/ml, 1250µg/ml, 625µg/ml, 312.5µg/ml, 156.25µg/ml, 78.125µg/ml, 39.06µg/ml, 19.53µg/ml and 9.76µg/ml. The CSP values are 8%, 18%, 42%, 56%, 54%, 59%, 55%, 62% 59% and 66% respectively. At a concentration ≥625µg/ml, the aqueous extract is toxic for cells. The CSP at 625µg/ml is 42%, hence toxic for cells. The cell survival percentage is more than 50% at a concentration > 625µg/ml, indicating that aqueous extract is more toxic to the cell than the rest of the three (Hexane, Chloroform, Ethanol extracts) at higher concentrations.