Interference Prevention in Size-Exclusion Chromatographic Analysis of Debranched Starch Glucans by Aqueous System

Lin, Amy Hui‐Mei; Chang, Yung‐Ho; Chou, Wen-Bin; Lu, Ting‐Jang

doi:10.1021/jf104393q

Cited by 12 publications

(2 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This in turn requires the value of the variation of refractive index with polymer concentration in the eluent, dn/dc. While a good MALLS signal is hard to obtain at low molecular weights, recent advances in MALLS detectors make this possible in systems in which the value of dn/dc is not too low, such as aqueous eluents [25] (note however that the value of dn/dc used in this reference was found with an amylodextrin of low DP obtained by degrading starch with HCl; this is a branched molecule, and because the value of dn/dc depends on the branching structure, the value is incorrect for the analyte, which is unbranched).…”

Section: Techniques and Assumptionsmentioning

confidence: 99%

Characterization Methods for Starch-Based Materials: State of the Art and Perspectives

Witt

Gilbert

2013

Aust. J. Chem.

View full text Add to dashboard Cite

Improving starch-containing materials, whether food, animal feed, high-tech biomaterials, or engineering plastics, is best done by understanding how biosynthetic processes and any subsequent processing control starch structure, and how this structure controls functional properties. Starch structural characterization is central to this. This review examines how information on the three basic levels of the complex multi-scale structure of starch -individual chains, the branching structure of isolated molecules, and the way these molecules form various crystalline and amorphous arrangements -can be obtained from experiment. The techniques include fluorophore-assisted carbohydrate electrophoresis, multipledetector size-exclusion chromatography, and various scattering techniques (light, X-ray, and neutron). Some examples are also given to show how these data provide mechanistic insight into how biosynthetic processes control the structure and how the various structural levels control functional properties.

show abstract

Section: Techniques and Assumptionsmentioning

confidence: 99%

Characterization Methods for Starch-Based Materials: State of the Art and Perspectives

Witt

Gilbert

2013

Aust. J. Chem.

View full text Add to dashboard Cite

show abstract

“…This in turn requires the value of the variation of refractive index with polymer concentration in the eluent, dn/dc. While a good MALLS signal is hard to obtain at low molecular weights, recent advances in MALLS detectors make this possible in systems in which the value of dn/dc is not too low, such as aqueous eluents [88] (note however that the value of dn/dc used in this reference was found with an amylodextrin of low DP obtained by degrading starch with HCl; this is a branched molecule, and because the value of dn/dc depends on the branching structure, the value is incorrect for the analyte, which is unbranched).…”

Section: Techniques and Assumptions For Starch Cld Experimental Analysismentioning

confidence: 99%

Theory of starch biosynthesis and their structures for the rational design of starches: a mathematical modelling approach

Wu¹

View full text Add to dashboard Cite

Starch is stored transiently in leaves during the day and degraded during the night to fuel respiration and continual growth. In seeds, starch is reserved for seed germination. We rely on starch as the main source of food energy and, in addition, it has a wide range of industrial applications. Rational design of starches for improved quality and quantity has significant global implications.This thesis describes an approach to study starch biosynthesis-structure relation through mathematical model developments. The structure of interest is the starch chain-length distribution (CLD). First, this thesis optimized procedures for obtaining accurate starch CLDs using sizeexclusion chromatography (SEC) and fluorophore-assisted carbohydrate electrophoresis (FACE) and found that the commonly used alkali dissolution method causes degradation in the long amylopectin chains and amylose chains. A milder dissolution procedure using dimethyl sulfoxide at 80°C was found to be effective at minimizing artifactual results. Mathematical models for both transient and reserve starch biosynthesis are presented in this thesis which involve linear algebra and differential equations. Analytical solutions and considerable insight is obtained by expressing the solutions in terms of eigenanalysis. Numerical solutions of the models were computed by FORTRAN programs developed in this thesis. These models provide a means by which a small number of key parameters defining the core enzymatic activities can be used to parameterize starch CLDs, providing the basis for focusing studies on the rational design of starch structure. The reserve-starch biosynthesis model predicts defined restrictions on particular ratios of enzymatic activities apply. The model independently proved the absolute requirement of debranching enzymes for the synthesis of starch previously inferred by genetic and biochemistry studies. The model provides a mechanistic basis for understanding how successive arrays of crystalline lamellae are formed, based on the identification of two independent types of long amylopectin chains, one type remaining in the amorphous lamella, while the other propagates into, and is integral to the formation of, an adjacent crystalline lamella. The defined restrictions on ratios of enzymatic activities predicted by the reserve-starch biosynthesis model imply that starch CLD cannot be dramatically altered if the plant is to be viable. However, the model suggests that altering the specificity of branching enzymes so that different chain lengths are transferred during branching is a workable option for producing starch with altered CLD. This prediction is tested in a collaborative work by mutating the conserved amino acids in the catalytic domain of maize branching enzyme IIa (mSBEIIa). One of the so produced mSBEIIa mutant (R436K) was capable of transferring chains with a degree of polymerization (DP) of 7 like the wild-type mSBEIIa. The reserve-starch biosynthesis model predicts that a higher branching enzyme activities causes a lower amo...

show abstract

In Vitro Digestibility and Predicted Glycemic Index of Chemically Modified Rice Starch by One‐Step Reactive Extrusion

Cai

Tian

et al. 2019

Starch Stärke

View full text Add to dashboard Cite

The in vitro digestibility of chemically modified rice starch by one‐step reactive extrusion (REX) via esterification, acetylation, hydroxypropylation, and cross‐linking or dual‐modification (hydroxypropylation‐cross‐linking and acetylation‐cross‐linking) is investigated. After REX processing, pasting viscosity is decreased, while the viscosity of esterification samples is lower than that of cross‐linking samples. Molecular structure analysis suggests that the degradation of starch molecules is retarded by esterification whereas enhanced by cross‐linking. Dual modification (hydroxypropylation and phosphorylation, hydroxypropylation‐cross‐linking (HP‐CL) sample) involving hydroxypropylation and phosphorylation (HP‐CL sample) is more conducive to preventing enzyme hydrolysis than the other modifications. HP‐CL sample achieves the lowest predicted glycemic index (pGI) value (88.1) and the highest RS content (15.3%). Thus, the one‐step REX is a useful method for reducing rice starch digestibility or pGI value.

show abstract

Interference Prevention in Size-Exclusion Chromatographic Analysis of Debranched Starch Glucans by Aqueous System

Cited by 12 publications

References 53 publications

Characterization Methods for Starch-Based Materials: State of the Art and Perspectives

Characterization Methods for Starch-Based Materials: State of the Art and Perspectives

Theory of starch biosynthesis and their structures for the rational design of starches: a mathematical modelling approach

In Vitro Digestibility and Predicted Glycemic Index of Chemically Modified Rice Starch by One‐Step Reactive Extrusion

Contact Info

Product

Resources

About