Mitochondrial energy homeostasis-mediated respiration suppression: A novel mechanism for combating wilting of Hericium erinaceus via electron beam generated X-ray irradiation

Abstract

This study explored the mechanism of Hericium erinaceus wilting delayed by 1.0 kGy electron-beam generated X-ray (EBGX) irradiation from modulating respiratory pathways and energy homeostasis perspectives. Results indicated that 1.0 kGy treatment enhanced the reducing power of nicotinamide adenine dinucleotide phosphate oxidized state by 12.1 % relative to the control group after storage. Moreover, the activities and transcript levels (HeCCO, HeSDH, HePDH) of cytochrome C oxidase, succinate dehydrogenase, 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase in H. erinaceus were significantly elevated in 1.0 kGy irradiation, whereas phosphoglucose isomerase activity and gene expression (HePGI) were diminished. Additionally, irradiation retained high mitochondrial function and energy status, as proved by higher levels of adenosine triphosphate (39.1 %), adenosine diphosphate (50.3 %), energy charge (29.3 %), and upregulated ATPase gene (HeATP1, HeATP2) expression on day 9. These findings suggested that EBGX irradiation retarded postharvest mushrooms wilting by enhancing the pentose phosphate and cytochrome pathways, optimizing energy homeostasis, and reducing mitochondrial dysfunction. Consequently, the positive synergistic regulation effect of fruiting body withered induced by respiratory and energy metabolism disorders was reflected in irradiation treatment, which may be a promising preservation strategy to mitigate the quality loss of edible fungi.