采后H2O2和茶多酚处理对草莓果实活性氧代谢和衰老的影响

摘要

[目的]探讨活性氧对草莓果实衰老的影响.[方法]试验以‘红颜’草莓果实为试材,采用H2O2和茶多酚处理采后草莓果实,研究促进和清除活性氧对草莓果实活性氧代谢和衰老的影响.[结果]在草莓果实采后衰老过程中,H2 O2处理、茶多酚处理和对照的果实腐烂指数和腐烂率均持续上升,H2 O2处理的腐烂指数和腐烂率始终高于对照,茶多酚处理的两者始终低于对照.H2 O2处理、茶多酚处理和对照的脂氧合酶(LOX)活性、过氧化氢(H2O2)含量、超氧阴离子(O2·-)产生速率、丙二醛(MDA)含量均上升.在果实衰老过程中,H2 O2处理的O2·-产生速率、MDA含量均高于对照,CAT活性和APX活性基本均低于对照;茶多酚处理后O2·-产生速率、MDA含量均低于对照,CAT活性和APX活性基本均高于对照.[结论]促进活性氧使果实保护酶活性下降,加剧了活性氧的上升积累,从而加速了草莓果实衰老;清除活性氧则提高了保护酶活性,缓减了活性氧的上升积累,从而延缓了果实衰老.%[Purpose] The study was to discuss the effect of reactive oxygen on senescence of strawberry fruit.[Method] The effects of soaking fruit with hydrogen peroxide (H2O2) and tea polyphenol (TP) on reactive oxygen metabolism and ageing were studied in postharvest ‘ Hongyan’ strawberry fruit.[Results] In ageing process,rot index and rotting rate of H2O2 trcatment,TP treatment and CK all continued to increase,rot index and rotting rate of H2O2 treatment were all higher than those of CK all the time,while rot index and rotting rate of TP treatment were all lower than those of CK all the time.In ageing process,lipoxygenase (LOX) activity,H2O2 content,superoxide anion radical (O2 ·-) production rates,malondialdehyde (MDA) content of H2O2 treatment,TP treatment and CK all increased.Furthermore,in whole ageing process,O2·-production rates,MDA content of H2O2 treatment were all higher than those of CK,while activities of CAT and APX were all lower than those of CK.O2 ·-production rates,MDA content of TP treatment were all lower than those of CK,while activities of CAT and APX were all higher than those of CK.[Conclusions] Promoting reactive oxygen lead to the decline of protective enzyme activities and intensified the accumulation of reactive oxygen,consequently accelerated fruit aging.However,eliminating reactive oxygen enhanced protective enzyme activities and relieved the accumulation of reactive oxygen,and postponed fruit aging.