INFLUENCE OF CHAIN-LENGTH OF SHORT MONODISPERSE AMYLOSES ON THE FORMATION OF A-TYPE AND B-TYPE X-RAY-DIFFRACTION PATTERNS
INFLUENCE OF CHAIN-LENGTH OF SHORT MONODISPERSE AMYLOSES ON THE FORMATION OF A-TYPE AND B-TYPE X-RAY-DIFFRACTION PATTERNS
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DOI：
10.1016/0141-8130(87)90034-1
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发表时间：
1987-04-01
影响因子：
8.2
通讯作者：
PFANNEMULLER, B
中科院分区：
文献类型：
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作者：
PFANNEMULLER, B
通过磷酸化合成（DP 20-35）和制备g.p.c.分离得到长度均匀的直链淀粉。-生物凝胶P-4 （DP 3-20）上的直链淀粉水解消化。纯水溶液在常温或低温下形成的结晶沉淀为DP 10-12的麦芽寡聚物提供了a型x射线图，为DP 13和所有较长的链提供了b型x射线图。通过这些仔细纯化的样品，没有观察到a -和b -直链淀粉模式的混合物。比dp10短的麦芽寡聚物没有结晶。这一发现支持了最近的研究，表明支链淀粉的平均链长与各种淀粉的x射线类型密切相关。链长对晶体堆积影响的原因还有待解决。
Amyloses of uniform length were obtained by phosphorlytic synthesis (DP 20-35) and by preparative g.p.c. fractionation of an .alpha.-amylolytic digest of amylose on Bio-Gel P-4 (DP 3-20). Crystalline precipitates formed from pure aqueous solution on standing at ambient or lower temperatures gave the A-type X-ray pattern for malto-oligomers of DP 10-12 and the B-type pattern for DP 13 and all longer chains. With these carefully purified samples a mixture of the A- and B-amylose pattern was not observed. Malto-oligomers shorter than DP 10 did not crystallize. The findings support recent studies, indicating that the average chain length of amylopectin and the X-ray type of various starches are closely related. The reason for an influence of chain length on crystalline packing remains to be resolved.