Antibacterial Activity of Indian Borage (Plectranthus amboinicus Benth) Leaf Extracts in Food Systems and Against Natural Microflora in Chicken Meat.

The ability of acetone and ethyl acetate extracts of the leaves of a traditional Indian
medicinal plant, Indian borage (Plectranthus amboinicus Benth) to prevent spoilage of artifi -
cially inoculated model food systems (cabbage and papaya) and natural microfl ora of
chicken meat was evaluated. These extracts were able to reduce the bacterial counts in all
food systems; however, the eff ective concentration varied with the complexity of the system
(cabbage<papaya<chicken). A probable mode of action of extracts was investigated by
analyzing the changes they cause in bacterial cell wall and leakage of nucleic acid from
bacterial cells. Both acetone and ethyl acetate extracts at their respective minimum inhibitory
concentrations resulted in leakage of cell constituents to an extent of 40 to 80 and 60 to
95 %, respectively, compared to the control, and fi nally leading to disintegration of cell
walls. These fi ndings indicate the potential use of ethyl acetate and acetone extracts of Indian
borage leaves in food preservation.