【摘要】 本文以葡萄、草莓、菠菜、芹菜和萝卜等果蔬为试材,通过利用DPPH光度分析法测定了果蔬在贮藏过程中体内总抗氧化能力的变化情况来反映果蔬体内防御能力的变化趋势。结果表明,果蔬在贮藏初期受到的环境胁迫较轻微,所产生的自由基被机体内较完善的防御系统清除,并且当自由基的产生超过体内防御系统的清除能力时,可诱导体内新的抗氧化防御系统的产生;但随着衰老的不断进行,自由基不断累积,果蔬体内新的抗氧化物质的合成能力下降,抗氧化能力也因不断耗竭而下降,当自由基的累积超过某一“阈值”后,就会加速果蔬的衰老与死亡。更多还原

【Abstract】 The research takes grape,strawberry,spinach,celery and radish as the experimental materials,and studies the changesof total TAA which is measured according to the spectrophotometric method using DPPH as free radical generator. We concludethat in initial storage period,the fruits and vegetables suffer slight stress,and free radicals can be scavenged by internal antioxidantivedefence system,and new isoforms are synthesized when free radicals level exceeds the activity of endogenous antioxidants.Alongwith the senescence and the accumulation of free radicals,the ability of synthesis of new isoforms and antioxidant activity willdecrease . Free radicals will accelerate the aging and death of fruits and vegetables after the level of free radicals increases to certaindegree.更多还原