Production and antimicrobial activity of sophorolipid against Clostridium perfringens and Campylobacter jejuni and their additive interaction with lactic acid

Abstract

Abstract The poultry industry experiences enormous economic losses due to microbial contamination, leading to searches for natural antimicrobials. Sophorolipid is a glycolipid produced by Starmerella bombicola, that acts as an emulsifier and antimicrobial agent. The aim of this research was to produce, characterize and apply sophorolipid from S. bombicola against the chicken pathogens Clostridium perfringens and Campylobacter jejuni, which are responsible for diseases that cause great damage to the poultry industry. The application of sophorolipid against these microorganisms has not yet been reported and to aggregate value to the product, sophorolipid was associated with lactic acid, a nontoxic molecule already utilized in the food industry. Sophorolipid production reached 69.83 g.L−1 with a productivity of 0.24 g.L−1.h−1 and a yield of 46.41% at 288 h in a bioreactor. The structural characterization analyses confirmed the predominance of the lactonic form. Sophorolipid demonstrated antimicrobial activity against the tested bacteria and the combined treatment of sophorolipid and lactic acid represented an additive interaction. Therefore, this combination could be an alternative to use as a new natural sanitizer in the poultry industry, reducing the microbial contamination of these main pathogens.