Cold plasma treatment maintains apricot fruit quality by regulating respiration and energy metabolism

Apricots rapidly ripen and senesce during storage, seriously impacting its commercialization. This work aimed to elucidate the function of cold plasma (CP) treatment on apricot fruit respiration and energy metabolism, and its relationship with fruit senescence. CP treatment significantly inhibited fruit decay, with a 54.8 % lower decay incidence than control (CK) on day 42. Compared with CK fruit, the activities of alternative oxidase (AOX), cytochrome c oxidase (CCO), succinate dehydrogenase (SDH), phosphoglucose isomerase (PGI), and hexokinase (HK), as well as their corresponding gene expression levels, were decreased in CP-treated fruit. Conversely, NAD kinase (NADK), glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH) activities and genes expression were increased. Additionally, CP-treated apricot showed lower nicotinamide adenine dinucleotide (NAD) and reduced nicotinamide adenine dinucleotide (NADH) contents and higher nicotinamide adenine dinucleotide phosphate (NADP) and reduced nicotinamide adenine dinucleotide phosphate (NADPH) contents. As regards energy metabolism, adenosine triphosphate (ATP), adenosine diphosphate (ADP) contents, energy charge (EC), and total adenosine triphosphatase (ATPase) activity in apricot were enhanced by CP treatment, while AMP content was decreased. In conclusion, CP treatment inhibited apricot fruit respiratory metabolism by downregulating the Embden–Meyerhof–Parnas pathway (EMP–TCA) cycle, the cytochrome pathway (CCP), the alternative oxidation pathway (AP), and upregulating the pentose phosphate pathway (PPP). This sustained a higher level of energy status and membrane structural integrity, and improved the preservation quality of apricot fruit • Cold plasma (CP) modified membrane permeability to decrease apricot’s respiratory rate • CP reduced cellular lipid oxidation by modulating pyridine nucleotide homeostasis • CP reduced apricot’s respiratory rate by regulating respiratory metabolic pathways • CP activated total ATPase activity to improve the energy status • CP was an effective technology for extending the shelf life of apricot fruit