Evaluation of antioxidant, phytochemicals and antibacterial potential of Mormordica charantia (Linn) against pathogenic bacteria isolated from ready to eat food sold in Akure Metropolis, Nigeria

Abstract

Abstract Background Food hygiene and safety is of utmost importance for public health, as it helps to protect the health of consumers from foodborne illnesses. Although, hundreds of plant species have been screened and tested for antimicrobial properties, the vast majority of these plants have not been adequately screened and evaluated. Considering the vast potentiality of plants as sources for antimicrobial drugs, the present research aimed to evaluate antioxidant, phytochemicals and determine the antibacterial activity of M. charantia (Linn) on pathogenic organism from Ready-to-eat food sold in Akure metropolis. Results Bacteria isolated from RTE food studied belong to the following genera; Staphylococcus, Streptococcus, Citrobacter, Pectobacterium, Klebsiella, Bacillus, Kocuria, Kluyveria, Serratia, Pantoea, Enterobacter and Salmonella. The antibiotic susceptibility pattern revealed that the Gram negative organisms were more susceptible to Gentamycin (30 µg) while Streptomycin (30 µg) was found to be more potent on Gram positive organisms. Water and ethanol extracts showed significant to moderate antibacterial activity toward all tested isolates except; Escherichia vulneris and Kluyveria intermedia which are both resistant to the aqueous extracts of M. charantia and the latter which was resistant to the ethanoic extract. The highest inhibitory activity was observed for Bacillus cereus with zone of inhibition of diameters 28 ± 0.29l (mm), followed by Escherichia vulneris 25 ± 0.29l (mm). DDPH% Inhibition has higher value in the water extract (69.21 ± 0.882a) while lower value was recorded in the ethanol extract (67.89 ± 0.155b). % Iron chelation has higher value in the ethanol extract (121.87 ± 0.882a) while lower value was recorded in the water extract (97.28 ± 0.155b). In all the concentration, vitamin C was higher in the ethanol extract than in the water extract. Conclusions The study revealed that all the Ready-to-eat food had a total bacterial count that are below potentially hazardous count although the presence of some microorganisms that are of health significance were observed. The study also confirmed that M. charantia (Linn) extracts had antibacterial effect against tested isolates from Ready-to-eat food sold in Akure metropolis. Based on the findings of this great research work, Mormordica charantia (Linn) possesses antioxidant activity that could prevent oxidative stress and degenerative diseases.

Keywords

• Antibacterial
• Mormordica charantia (Linn)
• Pathogenic bacterial
• Read-to-eat food