Preparation Of Amylose Research Articles

Isolation and Characterisation of Single Chain Amylose

Abstract Five amylose preparations of different origins (cassava, potato, smooth seeded pea, wheat and maize), obtained from native starch granules by thymol complexation, were ultracentrifuged as the final decontamination step to remove a high molecular weight population contaminating the amylose solutions. The efficiency of this ultracentrifugation procedure was assessed by dynamic light scattering (DLS): decreases in apparent hydrodynamic radii, R? H , from 46·1–72·6 nm before ultracentrifugation to 16·1–29·3 nm after were observed. Amylose solutions were then characterised by size exclusion chromatography coupled on-line to multi-angle laser light scattering (SEC–MALLS). Under these conditions M? w of cassava, potato, smooth seeded pea, wheat and maize amyloses were, respectively, 1·05×10 6 , 7×10 5 , 6·2×10 5 , 5·1×10 5 and 3·4×10 5 g/mol. Using a specific optimisation algorithm, experimental molecular weight distributions (MWD) were fitted by two mathematical models of ‘Most Probable’ distribution and ‘log-normal’ distribution. The best fit was obtained for the second model, but fitted M? w were higher than experimental M? w . When a ‘Most Probable’ model was used, the fitted M? w were consistent with experimental M? w but with a lower quality of fit. Exponents c in the power law R G = KM c were between 0·6 and 0·7, indicating an extended linear random coil in the range of MW analysed (3×10 5 –9×10 6 g/mol). This procedure was also applied to the characterisation of different commercial amylose products.

On the Susceptibility of the Crystalline and Retrograded Forms of Amylose of Different Molecular Weights toward Black-koji Amylase System

The crystalline and retrograded amylose preparations were digested by black-koji amylase system in the heterogeneous state such as in the case of raw starch digestion. It was found that the usual retrograded amylose should be fractionated into two parts—one easily digestible and the other resistant toward black-koji amylase system. The latter part, when recrystallized by n-butanol, however, turned highly susceptible toward the enzyme action. Its molecular weight, as determined by the light scattering method, was found to be 32,000, a value much smaller than that of the original amylose (140,000).

On the Susceptibility of the Crystalline and Retrograded Forms of Amylose of Different Molecular Weights toward Black-koji Amylase System

The crystalline and retrograded amylose preparations were digested by black-koji amylase system in the heterogeneous state such as in the case of raw starch digestion. It was found that the usual retrograded amylose should be fractionated into two parts—one easily digestible and the other resistant toward black-koji amylase system. The latter part, when recrystallized by n-butanol, however, turned highly susceptible toward the enzyme action. Its molecular weight, as determined by the light scattering method, was found to be 32,000, a value much smaller than that of the original amylose (140,000).

Determination ok amylase activity in biological fluids

A rapid method for the colorimetric determination of amylase activity in serum and urine is described. This method uses amylose as substrate; it is very simple to perform, uses only 0.4 ml of serum, and can be completed in approximately 25 minutes. Preparation of amylose and a criterion of purity of the product are given. The influence of various pertinent factors has been examined and is discussed. Application of the method to 100 cases and a working ·normal” range are given.

Streaming Birefringence Behavior of Some Subfractionated Amylose Preparations.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStreaming Birefringence Behavior of Some Subfractionated Amylose Preparations.Joseph F. Foster and Donald ZuckerCite this: J. Phys. Chem. 1952, 56, 2, 174–178Publication Date (Print):February 1, 1952Publication History Published online1 May 2002Published inissue 1 February 1952https://doi.org/10.1021/j150494a005RIGHTS & PERMISSIONSArticle Views16Altmetric-Citations3LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (604 KB) Get e-Alerts