Hydrolytic action of alpha-amylase on high-amylose starch of low molecular mass.
Hydrolytic action of alpha-amylase on high-amylose starch of low molecular mass.
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发表时间：
2000
影响因子：
2.8
通讯作者：
J. A. Rendleman
中科院分区：
文献类型：
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作者：
J. A. Rendleman
低平均聚合度的高直链淀粉（d-p 61-71）通过浸软芽孢杆菌环糊精葡聚糖转移酶与α-环糊精（CD）在2-70 ℃下相互作用形成为细颗粒，其高度不溶于水并且在正常烹饪条件（100 ℃）下不可胶凝。CD衍生的淀粉样品，无论是煮过的还是未煮过的，都在37 ℃下在选择的类似于人肠腔中的条件下通过人唾液α-淀粉酶进行体外水解。释放的低分子量淀粉进行了定量测定，并与天然淀粉的类似研究的结果进行了比较。在生淀粉中，CD衍生的淀粉显示出对α-淀粉酶的非常低的反应性，沿着马铃薯淀粉和高直链淀粉混合玉米淀粉（64%直链淀粉）。蒸煮大大提高了天然淀粉的反应活性，但仅适度增加了CD衍生淀粉的反应活性。蒸煮淀粉对水解的敏感性以以下一般顺序增加：CD衍生淀粉（约100%直链淀粉）<100%玉米直链淀粉（通过丁-1-醇方法分离）<杂交高直链淀粉玉米淀粉（64-66%直链淀粉）<蜡质玉米淀粉（99- 100%支链淀粉）约普通玉米淀粉（约25%直链淀粉）<马铃薯淀粉（约25%直链淀粉）。
High-amylose starches of low average degree of polymerization (d-p 61-71), formed as fine granules by interaction of Bacillus macerans cyclodextrin glucanotransferase with alpha-cyclodextrin (CD) at 2-70 degrees C, are highly insoluble in water and not gelatinizable under normal cooking conditions (100 degrees C). Samples of CD-derived starches, both cooked and uncooked, were subjected to hydrolysis in vitro by human salivary alpha-amylase at 37 degrees C under conditions chosen to resemble those in the human intestinal lumen. Released low-molecular-mass saccharides were determined quantitatively by HPLC and the results compared with those from similar studies with natural starches. Among uncooked starches, CD-derived starch showed very low reactivity towards alpha-amylase, along with potato starch and a high-amylose hybrid corn starch(64% amylose). Cooking greatly enhanced reactivity of natural starches, but only moderately increased reactivity of CD-derived starches. Susceptibility to hydrolysis of cooked starches increased in the following general order: CD-derived starch (approximately 100% amylose)<100%corn amylose (isolated by the butan-1-ol method)<hybrid high-amylose corn starch (64-66% amylose)<waxy maize starch (99-100%amylopectin) approximately ordinary corn starch ( approximately 25% amylose)<potato starch (approximately 25% amylose).