Influence of cultural conditions on hydrogen peroxide production by lactic acid bacteria isolated from some Nigerian traditional fermented foods

In this study, influence of cultural conditions on hydrogen peroxide production by lactic acid bacteria was investigated. Leuconostoc mesenteroides produced the highest quantity (0.024 L) of hydrogen peroxide while Lactobacillus plantarum produced the lowest amount (0.016 g/L) in normal MRS. The effect of temperature on hydrogen peroxide production was determined and the result showed that Leuc. mesenteroides produced the highest quantity (0.024 g/L) at 30 degrees C while L. brevis produced the lowest amount (0.012 g/L) of hydrogen peroxide at 45 degrees C. Leuc. mesenteroides produced the highest amount of hydrogen peroxide (0.032 g/L) when mannitol was used as the carbon source while Lactobacillus delbrueckii and Lactobacillus fermentum produced the lowest amount (0.020 g/L) when glucose was used as the carbon source. Furthermore, Leuc. mesenteroides produced the highest amount of hydrogen peroxide (0.033 g/L) when potassium nitrate was used as the nitrogen source while L. fermentum and L. delbrueckii produced the lowest amount (0.020 g/L) when yeast extract was used as the nitrogen source. Hydrogen peroxide produced by Leuc. mesenteroides has the highest zone of inhibition against Pseudomonas aeruginosa while hydrogen peroxide produced by L. plantarum had the lowest zone of inhibition against Staphylococcus aureus.