title: Postharvest temperature influences volatile lactone production via regulation of acyl-CoA oxidases in peach fruit.
abstract: The biosynthesis of volatile compounds in plants is affected by environmental conditions. Lactones are considered to be peach-like aroma volatiles; however, no enzymes or genes associated with their biosynthesis have been characterized. White-fleshed (cv. Hujingmilu) and yellow-fleshed (cv. Jinxiu) melting peach (Prunus persica L. Batsch) fruit were used as materials in two successive seasons and responses measured to four different temperature treatments. Five major lactones accumulated during postharvest peach fruit ripening at 20 °C. Peach fruit at 5 °C, which induces chilling injury (CI), had the lowest lactone content during subsequent shelf life after removal, while 0 °C and a low-temperature conditioning (LTC) treatment alleviated development of CI and maintained significantly higher lactone contents. Expression of PpACX1 and activity of acyl-CoA oxidase (ACX) with C16-CoA tended to increase during postharvest ripening both at 20 °C and during shelf life after removal from cold storage when no CI was developed. There was a positive correlation between ACX and lactones in peach fruit postharvest. Changes in lactone production in response to temperatures are suggested to be a consequence of altered expression of PpACX1 and long-chain ACX activity.
authors.affiliation: Laboratory of Fruit Quality Biology/The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Zijingang Campus, Hangzhou, Zhejiang, China.
authors.forename: Wan-Peng
authors.initials: WP
authors.lastname: Xi
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Liang
authors.forename: Ji-Yuan
authors.initials: JY
authors.lastname: Shen
authors.forename: Wen-Wen
authors.initials: WW
authors.lastname: Wei
authors.forename: Chang-Jie
authors.initials: CJ
authors.lastname: Xu
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Allan
authors.forename: Ian B
authors.initials: IB
authors.lastname: Ferguson
authors.forename: Kun-Song
authors.initials: KS
authors.lastname: Chen
mesh_terms: D042962:Acyl-CoA Oxidase / Q000235:genetics / Q000378:metabolism*; D018744:DNA, Plant / Q000235:genetics; D061353:Food Storage; D005638:Fruit / Q000201:enzymology / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D007783:Lactones / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D027861:Prunus / Q000201:enzymology* / Q000235:genetics; D017422:Sequence Analysis, DNA; D013696:Temperature; D055549:Volatile Organic Compounds / Q000378:metabolism*
chemical_list: D018744:DNA, Plant; D007783:Lactones; D010940:Plant Proteins; D055549:Volatile Organic Compounds; D042962:Acyl-CoA Oxidase