Phenyllactic acid maintains the storage quality of 'Zaosu' pears by regulating respiration and energy metabolism.

Respiration and energy metabolism are intricately linked to the quality and senescence of fruit after harvest. This investigation was carried out to examine alternations in quality parameters, respiration, and energy metabolism of 'Zaosu' pears subsequent to phenyllactic acid immersion. Results demonstrated that phenyllactic acid treatment led to a reduction in L * , a * , b * values, ΔE, and mass loss. Additionally, it maintained ascorbic acid, reducing sugar, soluble sugar, soluble solids, and chlorophyll contents; delayed the decrease in flesh firmness and titratable acidity of pears. The activities and gene expressions of glucose-6-phosphate dehydrogenase, glucose phosphate isomerase, hexokinase, nicotinamide adenine dinucleotide kinase, cytochrome C oxidase, and succinate dehydrogenasepears in pears were enhanced by phenyllactic acid. Moreover, phenyllactic acid promoted PbPK , PbAOX , PbH + -ATPase , and PbCa 2+ -ATPase expressions, while inhibiting malate dehydrogenase activity and the expressions of PbPFK and PbMDH in pears. Phenyllactic acid also led to a decrease in the levels of nicotinamide adenine dinucleotide hydrogen and nicotinamide adenine dinucleotide, while causing an increase in the levels of nicotinamide adenine dinucleotide phosphate hydrogen and nicotinamide adenine dinucleotide phosphate within the fruit. Collectively, postharvest phenyllactic acid treatment can effectively preserve the storage quality of 'Zaosu' pears by regulating the activity and gene expression of the key enzymes involved in respiration and energy metabolism. [Display omitted] • Phenyllactic acid maintained the storage quality of Zaosu pears. • Phenyllactic acid activated EMP, PPP and AP in pear fruit. • Phenyllactic acid enhanced key genes expressions in TCA cycle and energy metabolism. • Phenyllactic acid regulated pyridine nucleotides content and ensured energy supply. [ABSTRACT FROM AUTHOR]