Abstract:
Present study would be significant in the sustenance of quality characters for postharvest storage of Capsicum fruit with
CO2-sensitization in biocompatible manner. The present experiment describes effects of CO2 sensitization on delaying
postharvest ripening through physiological attributes in Capsicum fruit. The experiment was conducted with acidified
bicarbonate-derived CO2 exposure for 2 h on Capsicum fruit, kept under white light at 25 °C through 7 days postharvest
storage. Initially, fruits responded well to CO2 as recorded sustenance of greenness and integrity of fruit coat resolved
through scanning electron micrograph. Loss of water and accumulation of total soluble solids were marginally increased
on CO2-sensitized fruit as compared to non-sensitized (control) fruit. The ethylene metabolism biosynthetic genes like
CaACC synthase, CaACC oxidase were downregulated on CO2-sensitization. Accompanying ethylene metabolism cellular
respiration was downregulated on CO2 induction as compared to control through 7 days of storage. Fruit coat photosynthesis
decarboxylating reaction by NADP malic enzyme was upregulated to maintain the reduced carbon accumulation as recorded
on 7 days of storage under the same condition. CO2-sensitization effectively reduced the lipid peroxides as oxidative stress
products on ripening throughout the storage. Anti-oxidation reaction essentially downregulates the ROS-induced damages
of biomolecules that otherwise are highly required for food preservation during postharvest storage. Thus, the major finding
is that CO2-sensitization maintains a higher ratio of unsaturated to saturated fatty acids in fruit coat during storage. Tissuespecific downregulation of ROS also maintained the nuclear stability under CO2 exposure. These findings provide basic as
well as applied insights for sustaining Capsicum fruit quality with CO2 exposure under postharvest storage.
