Antimicrobial efficacy of liposomes containing d-Limonene and Its effects on shelf life of blueberry

Abstract. Investigation of antimicrobial activity of unilamellar nano vesicles (liposome) containing d-Limonene against selected fruit rotting fungi (Botrytis cinerea and Penicillium) and food borne illness causing bacteria (Escherichia coli and Listeria monocytogenes) was the purpose of this study. Furthermore, the research evaluated the extended the shelf life and enhanced food safety of the blueberry by d- limonene and liposomes. Liposomal nanoparticles were created by thin lipid film hydration followed by sonication. Mean liposome radius was 100.2 ±3.1nm. The antibacterial activity against E. coli showed 0.99 and 1.6 log 10 CFU/ml of reduction at 10I¼M and 50I¼M concentration respectively within 48 hours. The log 10 reduction was 1.6 at 10 I¼M and 3.4 at 50 I¼M concentration for L. monocytogenes. Germination of B. cinerea conidia was completely suppressed within 48 hours by 50 I¼M concentration of limonene. Liposomes exhibited 2.2 and 2.8 log 10 reduction of P. chrysogenum whereas 3.7 and 4.6 log 10 reduction were observed in B. cinerea for 10 and 50 I¼M limonene respectively in both fungus. The in vivo study of liposome coating on blueberries revealed protection against microbial growth even after 9 weeks of storage at 4°C. Liposomes reduced the blueberry storage loss by 50% at the end of 5 weeks. The result of this study can be used for enhancing food safety and extending shelf life of blueberries in produce industry and its application on a commercial scale.