Weissella cibaria DA2 cell-free supernatant improves the quality of sweet corn kernels during post-harvest storage

Sweet corn is susceptible to deteriorate for the high moisture and soluble sugar content. Lactic acid bacteria have good preservation effects on agricultural products, however, their application in preservation of sweet corns has been rare. In this study, the effect of Weissella cibaria DA2 cell-free supernatant (W. cibaria DA2 CFS) on the quality of sweet corns was investigated by morphological observation, quality indexes and metabolomics. Results showed that W. cibaria DA2 CFS could reduce malondialdehyde content, increase the soluble protein, soluble sugar and vitamin C content, and improve the activities of catalase, glutathione reductase and ascorbate peroxidase. Besides, phenylalanine metabolic pathway and biosynthesis of keratin, corky alkaloids and waxes might enhance the resistance of sweet corns. In conclusion, W. cibaria DA2 CFS could delay the quality deterioration of sweet corns. This research provided a theoretical basis for the application of W. cibaria DA2 CFS in the preservation of sweet corns.