Metatranscriptomic analysis of chitosan-coated fruit reveals dynamics in active microbiomes during banana ripening
摘要
Food-grade coatings, such as chitosan, can be used to delay ripening in fast-ripening fruits, such as bananas. However, most studies on chitosan coatings have focused on the fruit itself rather than on how the coating influences the microbial physiology around the fruit. Thus, this metatranscriptomics study was conducted to reveal the physiological dynamics of the active microbiome during banana ripening. In this study, RNA-seq metatranscriptomic analysis was performed on chitosan-coated and uncoated Cavendish bananas (Musa acuminata, group AAA) that live in banana fruits, and the data was analyzed. According to this study, the most abundant phyla in both groups were Proteobacteria, Firmicutes, and Actinobacteria (Pseudomonadota, Bacillota, and Actinobacteriota in the new taxonomic naming). In comparison to the control and time points of day 1 and day 7, the chitosan coating had a significant impact on both population diversity (tested using the Duncan post hoc test) and overall gene expression. Additionally, chitosan suppressed the expression of certain genes in specific microorganisms, particularly some aerobic microbes involved in specific metabolic processes, such as carbohydrate metabolism (B. aryabhattai, Ch. chaponense, and L. lactis), glutathione metabolism (So. canadensis and Pe. oryzae), and bacterial ethylene production (P. syringae). In conclusion, the chitosan coating on banana fruits seemed to alter the microbial community and physiology in comparison to the control samples, potentially influencing the banana ripening process both internally and externally through the microbiomes.