Biocontrol of Food Spoilage Microorganisms using Leaf extracts from Magnifera indica (Mango) and Psidium guajava (Guava).

Abstract

The shelf life of processed food is greatly reduced by spoilage microorganisms, which has resulted in great losses to food processors, wholesalers, retailers and even consumers. This study was aimed at controlling food spoilage microorganisms using leaf extracts from mango and guava. Fried meat (beef, chicken, grass-cutter, and goat meat), fried fish and fresh bread were purchased from Benin City, and left to spoil, after which spoilage organisms were isolated, identified and characterized using standard microbiological techniques. Mango and guava leaf extracts (ethanolic and aqueous), with Potassium sorbate and sodium nitrite was used. Significant highest (<0.05) (15.67±0.88 mg/ml) antibacterial activity of Mango leaf extract was recorded against Escherichia coli, and significant highest (<0.05) antifungal activity (19.67±0.33) was recorded against Penicillium oxalicum. Ethanolic leaf extracts of mango had better MICs (6.25 mg/ml) against E. coli tested than guava (25 mg/ml). In addition, ethanolic leaf extracts from Mango did not have any effect on Bacillus polymyxa. This study suggests that extracts from Mango and Guava leaves can be explored for controlling spoilage organisms; however, ethanolic extracts are more potent than aqueous extracts.