DEVELOPING A NEW ANTIMICROBIAL EDIBLE COATING FORMULATION BASED ON CARBOXYMETHYL CELLULOSE-SILVER NANOPARTICLES FOR TROPICAL FRUITS AND AN IN VITRO EVALUATION OF ITS ANTIMICROBIAL PROPERTIES

Tropical fruits including papaya are highly perishable especially during agents as an alternative packaging method have been employed widely in fruits to provide additional protection against postharvest diseases and prolong their shelf life. Silver nanoparticles (SNPs) have attracted intensive research interest due to their high antimicrobial properties. In the present study, antibacterial properties of edible surface coating based on sodium carboxymethyl cellulose (Na-CMC) incorporated with SNPs were investigated against Escherichia coli and Staphylococcus aureus. Results obtained indicated that the minimum bactericidal concentration of SNPs was 60 ppm. In vitro evaluation of antifungal properties of edible coating comprising of Na-CMC (1.32% w/w) – Na-caseinate (0.40% w/w ) – glycerol (0.86% w/w) – SNPs (60 ppm) against Colletotrichum musae, indicated that this coating formulation significantly (p<0.05) inhibited the growth of this fungus as compared to the same coating formulation without SNPs. Thus, these results indicated that Na-CMC-based coating formulation conjugated with SNPs can be employed as a new antimicrobial coating for tropical fruits to control diseases caused by microorganisms.