Preservation of microbial spoilage of food by biosurfactant-based coating

Objectives: Microbial spoilage of food is one of the leading causes of food scarcity worldwide, which could have devastating effect on the socioeconomic of any country. Along with classical food preservation methods, various innovative approaches can significantly increase the food safety. Biosurfactants are the amphiphilic microbial metabolites, while many of them have potential antimicrobial properties and therefore can be used for food preservation. Methods: During this study, three biosurfactants obtained from Bacillus subtilis (two of them) and Pseudomonas sp. (rhamnolipid) were screened for their antifungal activity against Aspergillus oryzae (MTCC 1846), Fusarium solani (MTCC 350), and Curvularia sp. by various in vitro and in vivo methods. Results: During this study, among three surfactants only Pseudomonas sp. biosurfactant (rhamnolipid) exhibited significant antifungal activity against A. oryzae, F. solani, and Curvularia sp. Further, the rhamnolipid coating (1 mg/ml) on lemon, potato and tomato protected them from fungal spoilage up to 15 days at room temperature in contrast to untreated samples which started spoiling in 6–7 days. Discussion: Above findings emphasis on the potential use of biosurfactants for the preservation of food items, however, a detailed study to ensure the safety of biosurfactant is of prerequisite.