کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1388797 982818 2009 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The molecular structure of waxy maize starch nanocrystals
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
The molecular structure of waxy maize starch nanocrystals
چکیده انگلیسی

The insoluble residues obtained by submitting amylopectin-rich native starch granules from waxy maize to a mild acid hydrolysis consist of polydisperse platelet nanocrystals that have retained the allomorphic type of the parent granules. The present investigation is a detailed characterization of their molecular composition. Two major groups of dextrins were found in the nanocrystals and were isolated. Each group was then structurally characterized using β-amylase and debranching enzymes (isoamylase and pullulanase) in combination with anion-exchange chromatography. The chain lengths of the dextrins in both groups corresponded with the thickness of the crystalline lamellae in the starch granules. Only ∼62 mol % of the group of smaller dextrins with an average degree of polymerization (DP¯) 12.2 was linear, whereas the rest consisted of branched dextrins. The group of larger dextrins (DP¯ 31.7) apparently only consisted of branched dextrins, several of which were multiply branched molecules. It was shown that many of the branch linkages were resistant to the action of the debranching enzymes. The distribution of branched molecules in the two populations of dextrins suggested that the nanocrystals possessed a regular and principally homogeneous molecular structure.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Carbohydrate Research - Volume 344, Issue 12, 17 August 2009, Pages 1558–1566
نویسندگان
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