α-淀粉酶对小麦糊化特性的影响  

The impact of α-amylase of normal mature wheat grain on starch pasting properties of wheat flour

作　　者：刘晓丹 潘志芬[1] 琚亮亮 李俏[1] 邓晓青[1] 代小梅 邓光兵[1] 龙海[1] 余懋群[1] 

机构地区：[1]中国科学院成都生物研究所,成都610041 [2]中国科学院大学,北京100049

出　　处：《应用与环境生物学报》2017年第6期1052-1058,共7页Chinese Journal of Applied and Environmental Biology

基　　金：国家重点基础研究发展计划(973计划)项目(2014CB138100)资助~~

摘　　要：淀粉糊化特性是反映淀粉品质的重要指标,与谷物的营养及加工性能有很强的相关性,而谷物中α-淀粉酶活性是影响淀粉糊化特性的重要因素,为了解我国正常成熟小麦的糊化特性受α-淀粉酶活性的影响,筛选了30份α-淀粉酶活性差异较大的小麦材料,进行降落值、总α-淀粉酶活性测定、α-淀粉酶蛋白电泳分离及糊化特性差异分析.结果显示:供试材料的降落值和总α-淀粉酶活性(OD值)差异很大,分别为62-524 s和0.12-2.87.根据降落值和总α-淀粉酶活性可将供试材料分为3类,I、Ⅱ、Ⅲ类的降落值分别为122.40(±20.25)s、373.67(±13.81)s、452.00(±3.39)s;总α-淀粉酶活性(OD值)分别为2.35(±0.21)、0.74(±0.06)、0.22(±0.00),这3类材料的总α-淀粉酶活性呈现显著差异且具有浓度差异明显的α-淀粉酶电泳条带;供试材料的糊化特性差异主要受基因型差异控制,受环境影响较小;迟熟α-淀粉酶显著降低小麦粉的峰值粘度、低谷粘度、最终粘度等多项糊化参数,并扩大材料间糊化特性差异.相关性分析表明,小麦籽粒α-淀粉酶活性与降落值极显著负相关(r=-0.97,P<0.01),与峰值粘度差值极显著正相关(r=0.84,P<0.01),降落值和峰值粘度差值都能较好地预测材料间α-淀粉酶活性的差异.本研究表明α-淀粉酶活性对淀粉糊化特性有显著降低的影响,在选择小麦育种或加工材料时应对材料的α-淀粉酶活性进行评估.Starch pasting, one of important starch properties, has a strong correlation with nutritional and processing properties of cereal grains. α-Amylase activity is one of the most important factors that affect the pasting properties of starch. However, there are few studies on the effect of α-amylase activity on the pasting properties of normal mature wheat grains in China. In this study, a total of 30 wheat cultivars were used for the determination of the falling number （FN）, total α-amylase activity, pasting properties of wheat flour with and without AgNO3, and SDS-PAGE separation of α-amylase protein. The analyzed wheat accessions showed wide variation in the total α-amylase activity （OD value） and FN, with a range of 0.12–2.87 and 62–524 s, respectively. According to the FN and total α-amylase activity, these accessions could be subdivided into three categories： FN was 122.40 （± 20.25） s, 373.67 （± 13.81） s, and 452.00 （ ± 3.39） s for categories I, II, and III, and the total α-amylase activity （OD value） was 2.35 （± 0.21）, 0.74 （± 0.06）, and 0.22 （± 0.00） for I, II, and III, respectively, each of them showed significant variations in the total α-amylase activity and had obvious differences in the intensity of SDS-PAGE α-amylase bands. The differences in starch pasting properties among the wheat accessions were mainly controlled by genotypes. Late maturity α-amylase significantly decreased pasting parameters of wheat flour, including peak viscosity, trough viscosity, and final viscosity, and enlarged the pasting differences among the wheat accessions. The total α-amylase activity in wheat significantly negatively correlated with FN （r = -0.97, P 〈 0.01） and with ΔPV （difference between peak viscosities with and without AgNO3） （r = 0.84, P 〈 0.01）. both FN and ΔPV predicted the difference in the total α-amylase activity among the wheat accessions. The wheat accessions under study showed significant variation in the total α-amylase activi

关 键 词：淀粉 Α-淀粉酶 糊化特性 SDS-PAGE 小麦品质 降落值 

分 类 号：TS201.25[轻工技术与工程—食品科学]