Author/Authors :
Khan, Muhammad Naseem Ocean University of China - College of Food Science and Engineering - Food Safety Laboratory, China , Khan, Muhammad Naseem Pakistan Council of Scientific and Industrial Research Laboratories Complex - Food and Marine Resources Research Centre (FMRRC), Microbiological Analytical Centre, Pakistan , Mirani, Zulfiqar Ali Pakistan Council of Scientific and Industrial Research Laboratories Complex - Food and Marine Resources Research Centre (FMRRC), Microbiological Analytical Centre, Pakistan , Wang, Jingxue Ocean University of China - College of Food Science and Engineering - Food Safety Laboratory, China , Lin, Hong Ocean University of China - College of Food Science and Engineering - Food Safety Laboratory, China , Khan, Seema Ismat Pakistan Council of Scientific and Industrial Research Laboratories Complex - Food and Marine Resources Research Centre (FMRRC), Microbiological Analytical Centre, Pakistan
Abstract :
Aims: This study investigated the effect of food preservatives on biofilm formation by food pathogens Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Methodology and results: Foodborne pathogens isolated from spices mix were analyzed for their resistance and biofilm formation in presence of certain traditional food preservatives. Sensitivity of pathogens against traditional preservative were tested by agar well diffusion method and agar dilution method. Biofilms growth were measured by crystal violet staining and distaining followed by absorbance at 563 nm. Biofilms were observed under electron microscope. P. aeruginosa was found to grow in Brain Heart Infusion broth supplemented with 7% ginger; similarly, E. coli and S. aureus also exhibited resistance to high level of garlic and sodium chloride, respectively. Although these pathogens belong to different classes e.g. S. aureus is a Gram-positive whereas E. coli and P. aeruginosa are Gram-negative. However, they employed similar strategy to nullify the toxic effect of food preservatives. During survival, these pathogens were found to change their living pattern from planktonic to biofilm mode of growth. Conclusion, significance and impact study: This study revealed that presence of resistant pathogens in food could nullify the impact of traditional food preservatives. The biofilm formation by pathogens could be potential hazard in traditionally preserved foods.
