Bacterial Quorum Sensing: Challenges and Prospects in Food Microbiology

Communication has long been considered as a unique activity of humans. But now it is found that communicative behaviour is present in all living systems including non-multicellular organisms and food fermentations. QS is a microbial communication method which depends on cell number that can control many activities in bacteria such as virulence, biofilm formation, competence and bioluminescence. For QS continuous secretion and observation of hormone-like molecules called auto-inducers or QS molecules is required. QS was first noticed in Gram-negative bacteria V. fischeri and termed as autoinduction (AI). After that it came to know that QS is present in many ecological niches. Unlike other environments in food matrix, QS molecules are produced but do not have regular distribution. External environment exerts its importance in varying sensing signals. In fact, physical factors, viz. pH, temperature, water and oxygen availability, are now known to influence the sensing processes. Spoilage of food may be defined as a process that makes food unattractive or deplorable for eating and outcome of microbial activity that ultimately dominates according to widespread ecological determinants. The present chapter will provide an outlook on (i) role of QS in food fermentation and food spoilage, (ii) factors that affect the activity of QS in various types of foods and inhibitors that can be used as biopreservatives, (iii) future perspectives that necessitated to understand how microbial behaviour in foods affects QS and (iv) utilization of QS in food preservation and food security.