作 者：
胡妍芸;李霁昕;王雨;王博;张国祥;张瑞君;蒋玉梅
单 位：
甘肃省兰州市红古区食品药品检验检测中心;甘肃农业大学食品科学与工程学院甘肃省葡萄与葡萄酒工程学重点实验室甘肃省葡萄酒产业技术研发中心
关键词：
苯并噻重氮;厚皮甜瓜;磷脂代谢;磷脂酶;基因表达;脂肪酸
摘 要：
磷脂是细胞膜的重要组分,磷脂代谢直接影响细胞膜的稳定性,进而影响植物的生长、衰老和次生产物代谢。诱抗剂苯并噻重氮(benzothiadiazole,BTH)可提高甜瓜(Cucumis melo L.)采后抗病性、延缓果实衰老、影响果实次生代谢产物香气物质的释放。本研究以‘玉金香’甜瓜为实验材料,于采后贮藏期间分析样品果实中磷脂酰胆碱(phosphatidyl cholines,PC)、磷脂酰肌醇(phosphatidylinositol,PI)和磷脂酸(phosphatidic acid,PA)含量以及磷脂酶A2(phospholipase A2,PLA2)、磷脂酶C(phospholipase C,PLC)和磷脂酶D(phospholipase D,PLD)活力和相关基因表达水平,探讨采后BTH处理调控厚皮甜瓜磷脂代谢的机理。结果表明:BTH处理可抑制厚皮甜瓜采后贮藏期间磷脂酶基因的表达和活力,果皮样磷脂酶活力峰值分别较CK组低7.11%(PLA2)、10.24%(PLC)和7.20%(PLD);BTH处理组膜磷脂组分PC、PI的积累量较CK组增加,贮藏结束时果皮样峰值比CK组高5.24%(PC)和2.08%(PI),BTH处理组磷脂代谢产物PA的含量较CK组、CC组降低,贮藏结束时,BTH处理组比CK组低20.72%(果皮)和8.51%(果肉);BTH对不饱和脂肪酸的抑制率低于饱和脂肪酸。可见,采后BTH处理可通过抑制PLC、PLD基因相对表达降低其活力,进而减少产物脂肪酸生成,改变脂肪酸不饱和度,然后影响细胞膜代谢过程中的信号传导和次生代谢产物生成,降低甜瓜果实的采后病害。
译 名：
Effect of Postharvest Benzothiadiazole Treatment on Membrane Phospholipid Metabolism of Thick-Skinned Muskmelon
作 者：
HU Yanyun;LI Jixin;WANG Yu;WANG Bo;ZHANG Guoxiang;ZHANG Ruijun;JIANG Yumei;Gansu Key Laboratory of Viticulture and Enology, Research and Development Center of Wine Industry of Gansu Province,College of Food Science and Engineering, Gansu Agricultural University;Lanzhou Honggu District Food and Drug Inspection Center of Gansu Province;
单 位：
HU Yanyun%LI Jixin%WANG Yu%WANG Bo%ZHANG Guoxiang%ZHANG Ruijun%JIANG Yumei%Gansu Key Laboratory of Viticulture and Enology, Research and Development Center of Wine Industry of Gansu Province,College of Food Science and Engineering, Gansu Agricultural University%Lanzhou Honggu District Food and Drug Inspection Center of Gansu Province
关键词：
benzothiadiazole;;thick-skinned muskmelon;;phospholipid metabolism;;phospholipase;;gene expression;;fatty acid
摘 要：
Phospholipids are one of the major constituents of cell membranes. Cell membrane stability is affected by phospholipid metabolism, in turn affecting plant growth, senescence and secondary metabolism. The plant resistance inducer benzothiadiazole(BTH) can improve disease resistance in muskmelon(Cucumis melo L.) after harvest, delay fruit senescence, and affect the production of aroma-active secondary metabolites. In the present work, we studied the changes in the contents of phosphatidyl cholines(PC), phosphatidylinositol(PI) and phosphatidic acid(PA) and the activities and gene expression levels of phospholipase A_2(PLA_2), phospholipase C(PLC) and phospholipase D(PLD) during the postharvest storage of muskmelon(Cucumis melo L. cv. Yujinxiang), and furthermore, we explored the mechanism of action of BTH in regulating phospholipid metabolism. The results showed that the activity and gene expression of phospholipase in pericarp were inhibited by BTH treatment during postharvest storage, and the activity peaks of PLA_2, PLC and PLD in pericarp were reduced by 7.11%, 10.24% and 7.20%, respectively, as compared to the control. BTH treatment augmented the accumulation of PC and PI over the control; the peak values at the end of storage increased by 5.24% and 2.08%, respectively. BTH treatment decreased PA level in comparison to the control and distilled water treatment; PA levels in pericarp and flesh of BTH treated fruits were 20.72% and 8.51% lower than those in the control. BTH treatment inhibited unsaturated fatty acids less than saturated fatty acids. Accordingly, BTH treatment can control postharvest diseases in muskmelon by inhibitingthe relative expression levels of PLC and PLD genes and reducing the enzyme activities and therefore decreasing fatty acid production and altering the degree of unsaturation of fatty acids, besides affecting the signal transduction pathways involved in cell membrane metabolism and the generation of secondary metabolites.
