甘薯块茎中β-淀粉酶同工酶特性及其在萌芽过程中的组织分布  

The Distribution of β-amylase and its Characteristics of Isoenzyme in Germinating Sweet Potato

作　　者：张原箕[1] 张华[1] 赵力[1] 张巧兰[1] 詹昌玲[1] 张亚利[1] 

机构地区：[1]合肥工业大学生物与食品工程学院,合肥230009

出　　处：《农产品加工（下）》2006年第10期53-56,共4页Farm Products Processing

基　　金：合肥工业大学大学生创新计划项目资助(XS0637)

摘　　要：采用聚丙烯酰胺凝胶活性电泳方法,以常用的甘薯品种“北京553”为研究材料,对甘薯块根中β-淀粉酶的部分生化特性进行了相关研究。发现甘薯块根中β-淀粉酶的最适温度为40℃,其温度稳定性范围为0～60℃,最适pH值为5.2～6.5,而pH值为3.0～8.0时酶具有较强的稳定性;考查金属离子对甘薯块根中β-淀粉酶的影响时发现,Ca2+与Zn2+对β-淀粉酶的活性及其同工酶谱带的变化不产生任何影响,Cu2+对β-淀粉酶同工酶的活性表现出了轻微的抑制效应,Pb2+对β-淀粉酶同工酶活性的抑制作用相对较大,Hg2+几乎抑制了β-淀粉酶各同工酶的全部活性。对萌芽过程中甘薯不同部位的β-淀粉酶进行了进一步分析,发现甘薯块根中β-淀粉酶的活性最高,幼芽中活性较低,而须根中几乎检测不到β-淀粉酶的活性。In this paper, characterization of β-amylase isozymes in the germinating ＂Beijng 553＂ sweet potato was studied using the method of native PAGE. The optimum temperature of amylase in sweet potatoes was 40 ℃, and they were stable in the temperature range 0-60 ℃ ; The optimum pH of these amylases was found to be 5.2-6.5, and they were stable in the pH range 3.0-8.0. It also showed that Cu^2＋ and Zn^2＋ had no apparent effects on these enzymes, while Cu^2＋ reduced the activities slightly and Pb2. inhibited the activities of the isozymes by 90% or more. Furthermore, Hg^2＋ inhibited the activities of the isozymes even at low concentration. To further investigate the distribution in different culture of the germinating sweet potato, the stem, root and shoot of sweet potato germinated for 7 d were utilized. The results showed that the activity of β -amylase was higher in stems than that of in roots and shoots.

关 键 词：甘薯 Β-淀粉酶 组织分布 

分 类 号：TS215[轻工技术与工程—粮食、油脂及植物蛋白工程]