1‐Butanol‐Hydrochloric Acid Hydrolysis of High‐Amylose Maize Starch. (14th March 2018)

• Record Type: Journal Article
• Authors: Hu, Xiuting; Wang, Yu; Liu, Chengmei; Jin, Zhengyu; Tian, Yaoqi
• Is Part Of: Stärke. Volume 70:Number 5/6(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-03-14
• Subjects: 1‐butanol‐HCl hydrolysis -- amylomaize V -- crystallinity -- granules -- molecular weight; Starch -- Periodicals; 572.566
• DOI: 10.1002/star.201700359
• Languages: English
• ISSNs: 0038-9056

Abstract

Abstract : The 1‐butanol‐hydrochloric acid (1‐butanol‐HCl) degradation mechanism of high‐amylose maize starch, represented by amylomaize V, is investigated using different methods. More pores are formed in the amylomaize V granules during 1‐butanol‐HCl hydrolysis and these pores become larger and change into cracks. Correspondingly, the average granule size slightly decreases from 13.49 to 10.87 µm after 1‐butanol‐HCl hydrolysis for 7 d. The crystalline areas of amylomaize V are hydrolyzed by 1‐butanol‐HCl and the amylose‐1‐butanol complex might form. In addition, the weight‐average molecular weight of amylomaize V dramatically decreases from 1.25 × 10 7 to 3.57 × 10 5 Da after hydrolysis for 4 h, then slowly decreases, and stabilizes at about 2.00 × 10 4 Da after hydrolysis for 4 d, which is in accordance with the result of iodine staining analysis. High‐performance anion‐exchange chromatography analysis indicates that 1‐butanol‐HCl can hydrolyze the starch like hydrolysis patterns of both the endo‐enzyme and the exo‐enzyme. These results suggests that HCl in 1‐butanol quickly diffuses into the whole amylomazie V granule and simultaneously attacks the crystalline and disorder areas, while the compact periphery of amylomaize V keeps the granules from disintegrating. Abstract : This work characterizes granule, crystallinity and molecular structure of native and 1‐butanol‐HCl hydrolysis amylomaize V. 1‐Butanol‐HCl degrades the starch molecules quickly, but the starch kept the granule and crystallinity well. Therefore, it was inferred that 1‐butanol‐HCl primarily hydrolyzes the amorphous part of amylomaize V and the compact periphery keeps amylomaize V from disintegration.