Inhibitory Pattern of Seafood-borne Bacteria in Mackerel against Nisapline

Indian mackerel (Rastrelliger kanagurta) procured from various outlets of Mysore market in different days were analyzed for coliforms and total plate count. Seafood-borne spoilage bacteria and pathogens such as Staphylococcus aureus, Bacillus cereus, Vibrio parahaemolyticus, Listeria monocytogenes and Pseudomonas spp were also isolated from the spoiled mackerels and their growth patterns were studied against nisin by "Well diffusion method". The results showed that nisin inhibited most of the Gram-positive bacteria. Selected seafood-borne spoilage bacteria such as S. aureus, B.cereus, L. monocytogenes and Gram-negative bacteria such as Pseudomonas spp were coated individually on the cooked disintegrated mackerel meat at 1 and 5% levels and incubated for three days at 37 °C. The growth patterns of these bacteria were studied against nisin. All the Gram-positive bacteria coated were inhibited by nisin but among Gram-negative bacteria, inhibition was observed only on Pseudomonas spp in "Well diffusion Method".