Combining molecular weight distribution (MWD) data for linear chains of debranched starch from capillary electrophoresis and from size exclusion chromatography (SEC) with detection by differential refractive index and by multi-angle laser light scattering has enabled Mark-Houwink parameters to be determined for linear starch chains. For accurate results, it was found to be important to take SEC band broadening into account, and a methodology for implementing this is presented. This deconvolution technique can be used to reveal features such as maxima or shoulders in the MWD which have qualitative as well as quantitative significance. Remarkably, these data show that the empirical Mark-Houwink relation between molecular weight and hydrodynamic volume is, for linear debranched starch, valid for much lower molecular weights than synthetic polymers. This implies that these Mark-Houwink parameters can be used with "universal calibration" to enable SEC to be used with relative ease to provide MWDs for debranched starch for essentially any degree of polymerization.
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http://dx.doi.org/10.1021/bm050041t | DOI Listing |
Plant Physiol
January 2025
Institute of Molecular Plant Biology, ETH Zurich, 8092 Zurich, Switzerland.
Plant chloroplasts store starch during the day, which acts as a source of carbohydrates and energy at night. Starch granule initiation relies on the elongation of malto-oligosaccharide primers. In Arabidopsis thaliana, PROTEIN TARGETING TO STARCH 2 (PTST2) and STARCH SYNTHASE 4 (SS4) are essential for the selective binding and elongation of malto-oligosaccharide primers, respectively, and very few granules are initiated in their absence.
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December 2024
Key Laboratory of Grain and Oil Processing and Food Safety of Sichuan Province, College of Food and Bioengineering, Xihua University, Chengdu 610039, China.
The processing properties of resistant starch (RS) and its digestion remain unclear, despite the widespread use of autoclaving combined with debranching in its preparation. In this study, the physicochemical, rheological and digestibility properties of autoclaving modified starch (ACB), autoclaving-pullulanase modified starch (ACPB) and native black Tartary buckwheat starch (NB) were compared and investigated. The molecular weight and polydispersity index of modified starch was in the range of 0.
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December 2024
College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an 710062, China.
Starches with different degrees of debranching (DBS30, DBS60, and DBS90) and sodium alginate were used as the wall material for encapsulating particles of GG (LGG). The structural characteristics of these encapsulated particles were examined, along with the impact of varying levels of debranching on the encapsulation efficiency, the in vitro release of LGG under the simulated gastrointestinal environment, and the storage stability of the encapsulated particles. The results revealed a transformation in the crystalline polymorph from C- to B+V-type following debranching and retrogradation.
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December 2024
College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian, PR China; Fujian Provincial Key Laboratory of Quality Science and Processing Technology in Special Starch, Fuzhou, Fujian, PR China. Electronic address:
Lotus seeds represent a significant economic crop and are abundant in starch. To further enhance their application value, this study investigates the structural characteristics of lotus seed starch (LS) under the combined influence of pullulanase and high hydrostatic pressure (HHP). Pullulanase increased amylose content from 39.
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December 2024
College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province 266109, China; Qingdao Special Food Research Institute, Qingdao 266109, China. Electronic address:
A novel strategy was developed to embed retrograded short-chain amylose (RSCA) into calcium alginate (CA) at varying concentrations (0.25 %, 0.5 %, 0.
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