CAJ | 학술논문

多酚氧化酶(PPO)是蔬果酶促褐变的关键酶,抑制该酶活性是防止蔬果褐变的有效措施.在实验中发现NaHSO_3对马铃薯PPO具有显著的抑制作用及在马铃薯切片护色中具有防褐变功能.实验结果表明:马铃薯PPO催化 L -多巴形成的褐变物质在475 nm波长处有特征性的吸收峰,并且该吸收峰随着NaHSO_3浓度的增加明显降低.NaHSO_3的抑制作用表现为不可逆效应,既可以延长酶促反应的迟滞时间,也降低了稳态的酶活力.当NaHSO_3浓度增至0.12 mmol/L时,酶促反应的迟滞时间从0延长至56 s,稳态的酶活力下降了35.5%.在马铃薯切片保鲜实验中,对照组在第3天褐变指数达到2,第6天已经完全褐变,而50 mmol/L NaHSO_3处理的实验组在第6天褐变指数仅为0.6,有效遏制了马铃薯切片的酶促褐变,实验显示,NaHSO_3通过抑制马铃薯PPO活力实现防褐变的效应.
다분양화매(PPO)시소과매촉갈변적관건매,억제해매활성시방지소과갈변적유효조시.재실험중발현NaHSO_3대마령서PPO구유현저적억제작용급재마령서절편호색중구유방갈변공능.실험결과표명:마령서PPO최화 L -다파형성적갈변물질재475 nm파장처유특정성적흡수봉,병차해흡수봉수착NaHSO_3농도적증가명현강저.NaHSO_3적억제작용표현위불가역효응,기가이연장매촉반응적지체시간,야강저료은태적매활력.당NaHSO_3농도증지0.12 mmol/L시,매촉반응적지체시간종0연장지56 s,은태적매활력하강료35.5%.재마령서절편보선실험중,대조조재제3천갈변지수체도2,제6천이경완전갈변,이50 mmol/L NaHSO_3처리적실험조재제6천갈변지수부위0.6,유효알제료마령서절편적매촉갈변,실험현시,NaHSO_3통과억제마령서PPO활력실현방갈변적효응.
Polyphenoloxidase(PPO)is key enzyme of enzymatic browning during vegetables and fruits storage.It is an essential and effective way to inhibit the polyphenol oxidase activity in the fresh-keeping of vegetables and fruits.In this paper,the inhibitory effects on potato PPO and color-preservation effects on potato slice of sodium bisulfite have been studied.The results show that the inhibition of sodium bisulfite on PPO is an irreversible reaction and that sodium bisulfite can result in prolonging the lag time of the enzyme reaction,and decreaseing the steady-state rate of the enzyme activity.When the concentration of sodium bisulfite reached to 0.12 mmol/L,the enzyme activity lost about 35.5% and the lag time increased from 0 to 56 s.The potato slice of the control group was half browned after 3 days,and entirely browned after 6 days.While treated by 50 mmol/L of sodium bisulfite,the browning index of the test group was only 0.6,indicating that sodium bisulfite could stop the enzymatic browning of potato slice efficaciously by inhibiting the potato polyphenol oxidase activity.