外源过氧化氢处理对采后荔枝褐变及活性氧代谢的影响  

Effects of exogenous hydrogen peroxide treatment on browning and reactive oxygen metabolism of postharvest litchi

作　　者：潘家丽 覃子倚 李静 Khoo Hock Eng 董新红 PAN Jia-li;QIN Zi-yi;LI Jing;Khoo Hock Eng;DONG Xin-hong(College of Chemistry and Bioengineering,Guilin University of Technology/Guangxi Key Laboratory of Electrochemical and Magneto-chemical Functional Materials,Guilin,Guangxi 541004,China)

机构地区：[1]桂林理工大学化学与生物工程学院/广西电磁化学功能物质重点实验室,广西桂林541004

出　　处：《南方农业学报》2022年第5期1227-1234,共8页Journal of Southern Agriculture

基　　金：国家自然科学基金项目(31760472);广西电磁化学功能物质重点实验室研究基金项目(EMFM20211108)。

摘　　要：【目的】研究外源过氧化氢(H_(2)O_(2))处理对采后荔枝褐变及活性氧代谢的影响,为荔枝采后保鲜提供途径,以期提高果实的贮藏品质。【方法】以清水处理为对照(CK),采用不同浓度(1、5和10 mmol/L)的外源H_(2)O_(2)浸泡荔枝3 min,在4℃下冷藏放置,每隔3 d取样一次,进行失重率、褐变指数、丙二醛(MDA)含量、细胞膜透性、内源H_(2)O_(2)含量、超氧阴离子(O_(2)-)产生速率、多酚氧化酶(PPO)活性和超氧化物歧化酶(SOD)活性等生理指标的测定。【结果】不同浓度的外源H_(2)O_(2)处理对采后荔枝会产生不同的贮藏效果。以5 mmol/L外源H_(2)O_(2)处理保鲜效果最佳,明显降低果皮中MDA含量、内源H_(2)O_(2)含量和PPO活性,并提高SOD活性,减缓O_(2)-产生速率。至贮藏末期(12 d),经5 mmol/L外源H_(2)O_(2)处理的采后荔枝SOD活性较CK显著提高31.41%(P<0.05,下同),MDA含量、PPO活性、O_(2)-产生速率和内源H_(2)O_(2)含量较CK分别降低44.72%、38.72%、22.63%和13.75%,其失重率、褐变指数和相对电导率最低。1 mmol/L外源H_(2)O_(2)处理效果稍逊于5 mmol/L外源H_(2)O_(2)处理,而经10 mmol/L外源H_(2)O_(2)处理显著提高采后荔枝的MDA和内源H_(2)O_(2)含量,加速采后果实衰老。【结论】采用5 mmol/L外源H_(2)O_(2)处理可调节采后荔枝的活性氧代谢而延缓其衰老进程,为H_(2)O_(2)应用于采后荔枝保鲜提供理论支撑。【Objective】To explore the effects of exogenous hydrogen peroxide(H_(2)O_(2)) treatment on browning and reac-tive oxygen metabolism of postharvest litchi,so as to provide a method to keep litchi fresh after harvest and improve the storage quality of litchi.【Method】Litchi was used as material,in contrast to clean water(CK),and soaked with different concentrations(1,5,10 mmol/L)of exogenous H_(2)O_(2)for 3 min,and then placed under 4℃,measured once every 3 d,weight loss rate,browning index,malondialdehyde(MDA)content,cell membrane permeability,endogenous H_(2)O_(2)con-tent,superoxide anion(O_(2)-)production rate,polyphenol oxidase(PPO)activity,superoxide dismutase(SOD)activity and other physiological indicators were determined.【Result】Different concentrations of exogenous H_(2)O_(2) treatment could pro-duce different storage effects on postharvest litchi.5 mmol/L exogenous H_(2)O_(2) treatment had the best preservation effect,and it could decrease MDA content,endogenous H_(2)O_(2) content and PPO activity in fruit peel,increase SOD activity,and slow down the production rate of O_(2)-.At the end of storage(12 d),SOD activity of postharvest litchi treated with 5 mmol/L exogenous H_(2)O_(2) treatment significantly increased by 31.41%(P<0.05,the same below)compared with CK.Compared with CK,MDA content,PPO activity,O_(2)-production rate and endogenous H_(2)O_(2) content were decreased by 44.72%,38.72%,22.63%and 13.75%,respectively,and weight loss rate,browning index and relative conductivity of postharvest lit-chi were the lowest.The effect of 1 mmol/L exogenous H_(2)O_(2)treatment was slightly inferior to that of 5 mmol/L exogenous H_(2)O_(2)treatment,while 10 mmol/L exogenous H_(2)O_(2)treatment significantly increased MDA content and endogenous H_(2)O_(2)content in postharvest litchi,and accelerated the senescence of post-harvest fruits.【Conclusion】5 mmol/L exogenous H_(2)O_(2)treatment can delay the senescence process of litchi by regulating the metabolism of reactive oxygen species,which will provi

关 键 词：过氧化氢(H_(2)O_(2)) 荔枝 褐变 活性氧代谢 

分 类 号：S667.109.3[农业科学—果树学]