Bacillus mojavensis enhances the antioxidant defense mechanism of soursop (Annona muricata L.) fruits during postharvest storage

The objective of this study aims to gain an insight into the effect of Bacillus mojavensis on the activity and gene expression of antioxidant defense enzymes in soursop fruits during postharvest storage. Our findings indicate different responses in the fruits inoculated with B. mojavensis at biochemical and molecular levels. On day one, fruits inoculated with B. mojavensis presented a mean value of 79.09 GAE/100 gFW in total phenols, and higher superoxide dismutase (SOD) and catalase (CAT) activities (1.35 and 1.78-fold higher, respectively). On the other hand, on the third day of storage, the ferric reducing/antioxidant power (FRAP) reached its highest level, including an increase in the expression of SOD, and PPO genes by 18.7-fold and 4.5-fold in fruits inoculated with B. mojavensis. Finally, on the fifth day of storage, soursop fruits inoculated with B. mojavensis had the highest mean values for 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH·), 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonate (ABTS· +), with values of 194.68 EAA/100 gFW, and 172.33 EAA/100 gFW, respectively. Indeed, higher polyphenol oxidase (PPO), and peroxidase (POD) activities (2.17-fold and 1.27-fold higher, respectively) were recorded compared to the control fruits. We show that depending on the stage of ripening, the antagonist bacteria B. mojavensis enhanced the antioxidant capacity, enzymatic activity, and gene expression of soursop fruits.PMID:36029413 | DOI:10.1007/s00203-022-03199-9
Source: Archives of Microbiology - Category: Microbiology Authors: Source Type: research