Author(s):
A Sangeetha, P Senthil Kumar, S Balakrishnan, K Manimaran, M Dhanalakshmi and T Sivakumar
Abstract:
The antimicrobial activity of ethanol extract of leaves of
Madhuca indica and Cassia fistula was tested against food-borne pathogens including two species of Gram-negative
bacteria
(
E. coli O157:H7 and
Salmonella enteriditis) and two species of Gram-positive bacteria
(
Listeria monocytogenes and methicillin–resistant Staphylococcus aureus) using disc diffusion method. In addition, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of plant extracts were determined. In the disc diffusion method, both the plants extracts were effective in reducing the bacterial growth of tested food-pathogens. The zone inhibition of ranged from 16 to 19 mm for
Madhuca and 12 to 13 mm for
Cassia plant extracts.
Madhuca indica extracts were effective in reducing bacteria growth compared to
Cassia fistula extracts (
p<0.05). The MIC of
Madhuca and
Cassia plant extracts ranged from 0.6 to 0.8% and 0.9 to 1.1%, respectively whereas MBC of
Madhuca and
Cassia plant extracts ranged from 1.5 to 1.7% and 2.5 to 2.6%, respectively. The results of the study suggest that the extracts from leaves of both
Cassia fistula and
Madhuca indica plants could be potentially used as natural food preservatives to control and prevent food-borne pathogens. However, further studies on the toxicities and organoleptic properties of food containing plant extracts are needed before recommending their usage.