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Amylopectin
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Jay-lin Jane – One of the best experts on this subject based on the ideXlab platform.
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chemical and physical properties of kiwifruit actinidia deliciosa starch
Starch-starke, 2006Co-Authors: David G Stevenson, Jay-lin Jane, Scott R Johnson, George E. InglettAbstract:Chemical and physical properties of kiwifruit (Actinidia deliciosa var. ‘Hayward’) starch were studied. Kiwifruit starch granules were compound, irregular or dome-shaped with diameters predominantly 4-5 μm or 7-9 μm. Kiwifruit starch exhibited B-type X-ray diffraction pattern, an apparent amylose content of 43.1% and absolute amylose content of 18.8%. Kiwifruit Amylopectins, relative to other starches, had low weight-average molecular weight (7.4 × 10 7 ), and gyration radius (200 nm). Average Amylopectin branch chain-length was long (DP 28.6). Onset and peak gelatinization temperatures were 68.9°C and 73.0°C, respectively, and gelatinization enthalpy was high (18.5 J/g). Amylose-lipid thermal transition was observed. Starch retrograded for 7 d at 4°C had a very high peak melting temperature (60.7°C). Peak (250 RVU), final (238 RVU) and setback (94 RVU) viscosity of 8% kiwifruit starch paste was high relative to other starches and pasting temperature (69.7°C) was marginally higher than onset gelatinization temperature. High paste viscosities and low pasting temperature could give kiwifruit starch some advantages over many cereal starches.
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structural and physicochemical characteristics of winter squash cucurbita maxima d fruit starches at harvest
Carbohydrate Polymers, 2005Co-Authors: David G Stevenson, Paul L Hurst, Jay-lin JaneAbstract:Abstract Structures and physicochemical properties of starch isolated from fruit (pepo) of seven winter squash cultivars ( Cucurbita maxima D.) were studied. Squash starches exhibited the B-type X-ray diffraction pattern and had most granules with diameters of 1.5–2.5, 6–8, and 11–13 μm. Squash Amylopectin had more long branch chains (25.4–29.3% DP≥37), and squash starch had relatively small absolute amylose contents (12.9–18.2%). Squash starch Amylopectins had weight-average molecular weights ranging from 2.03 to 3.22×10 8 g/mol, gyration radii of 294–337 nm, and unusually low polydispersity (1.21–1.81). Isoamylase-debranched Amylopectins showed average chain-length varied from DP 26.5 to 28.1. Squash starches had onset gelatinization temperature ranging from 60.6 to 63.5 °C and enthalpy changes (Δ H ) from 15.9 to 17.4 J/g. Retrogradation rate for squash starches ranged from 41 to 55% after 7 days at 4 °C. Squash starch pastes, measured by using a Rapid Visco-Analyzer, had peak viscosity of 174–233 RVU, final viscosity of 193–244 RVU, and setback of 79–100 RVU, with pasting temperature of 65.6–68.8 °C.
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Structures and Properties of Amylopectin and Phytoglycogen in the Endosperm of sugary-1 Mutants of Rice
Journal of Cereal Science, 2003Co-Authors: Kit-sum Wong, Jay-lin Jane, Akiko Kubo, Kyuya Harada, Hikaru Satoh, Yasunori NakamuraAbstract:Starch debranching enzyme (DBE)-deficient, sugary-1 mutations of rice caused the biosynthesis of more highly branched α-glucan in the form of phytoglycogen and sugary –Amylopectin rather than wild-type Amylopectin. Phytoglycogen and sugary –Amylopectin are located in the inner and outer regions of the rice endosperm, respectively. Detailed analyses of these glucans from a variety of allelic mutants with different severity of sugary phenotype revealed that sugary –Amylopectins consisted of more short chains of DP
Yasunori Nakamura – One of the best experts on this subject based on the ideXlab platform.
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the structure of starch can be manipulated by changing the expression levels of starch branching enzyme iib in rice endosperm
Plant Biotechnology Journal, 2004Co-Authors: Naoki Tanaka, Hikaru Satoh, Naoko Fujita, Aiko Nishi, Yuko Hosaka, Masashi Ugaki, Shinji Kawasaki, Yasunori NakamuraAbstract:Summary
When the starch branching enzyme IIb (BEIIb) gene was introduced into a BEIIb-defective mutant, the resulting transgenic rice plants showed a wide range of BEIIb activity and the fine structure of their Amylopectins showed considerable variation despite having the two other BE isoforms, BEI and BEIIa, in their endosperm at the same levels as in the wild-type. The properties of the starch granules, such as their gelatinization behaviour, morphology and X-ray diffraction pattern, also changed dramatically depending on the level of BEIIb activity, even when this was either slightly lower or higher than that of the wild-type. The over-expression of BEIIb resulted in the accumulation of excessive branched, water-soluble polysaccharides instead of Amylopectin. These results imply that the manipulation of BEIIb activity is an effective strategy for the generation of novel starches for use in foodstuffs and industrial applications. -
Structures and Properties of Amylopectin and Phytoglycogen in the Endosperm of sugary-1 Mutants of Rice
Journal of Cereal Science, 2003Co-Authors: Kit-sum Wong, Jay-lin Jane, Akiko Kubo, Kyuya Harada, Hikaru Satoh, Yasunori NakamuraAbstract:Starch debranching enzyme (DBE)-deficient, sugary-1 mutations of rice caused the biosynthesis of more highly branched α-glucan in the form of phytoglycogen and sugary –Amylopectin rather than wild-type Amylopectin. Phytoglycogen and sugary –Amylopectin are located in the inner and outer regions of the rice endosperm, respectively. Detailed analyses of these glucans from a variety of allelic mutants with different severity of sugary phenotype revealed that sugary –Amylopectins consisted of more short chains of DP
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structures and properties of Amylopectin and phytoglycogen in the endosperm of sugary 1 mutants of rice
Journal of Cereal Science, 2003Co-Authors: Kit-sum Wong, Jay-lin Jane, Akiko Kubo, Kyuya Harada, Hikaru Satoh, Yasunori NakamuraAbstract:Starch debranching enzyme (DBE)-deficient, sugary-1 mutations of rice caused the biosynthesis of more highly branched α-glucan in the form of phytoglycogen and sugary –Amylopectin rather than wild-type Amylopectin. Phytoglycogen and sugary –Amylopectin are located in the inner and outer regions of the rice endosperm, respectively. Detailed analyses of these glucans from a variety of allelic mutants with different severity of sugary phenotype revealed that sugary –Amylopectins consisted of more short chains of DP<12 but fewer chains of DP13–24 than did wild-type Amylopectin, and the alterations reflected on lower molecular weights, smaller gyration radii, and denser molecules. These changes resulted in lower onset gelatinization temperature, lower peak viscosity, lesser degree of crystallinity, and smaller and cracked granules with rough surface of sugary starch granules as compared with that of the wild-type. These results indicate that changes in the fine structure of Amylopectin induced by lesion of DBE greatly influence the morphological and physicochemical properties of starch. Phytoglycogens from sugary-1 mutants were composed of multiple components of smaller molecular weights and gyration radii than sugary –Amylopectin and Amylopectin. The highly branched phytoglycogens were more tightly packed molecules exhibiting greater dispersed densities than sugary –Amylopectin and Amylopectin. These results suggest that the levels of DBE in rice endosperm control the biosynthetic pathway of branched α-glucans and produce Amylopectin, sugary –Amylopectin and phytoglycogen.
Paul Colonna – One of the best experts on this subject based on the ideXlab platform.
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molecular and supra molecular structure of waxy starches developed from cassava manihot esculenta crantz
Carbohydrate Polymers, 2013Co-Authors: Agnes Rollandsabate, Paul Colonna, Dominique Dufour, Teresa Sanchez, Alain Buleon, Hernan Ceballos, Shanshan Zhao, Peng ZhangAbstract:Abstract The aim of this work was to characterize the Amylopectin of low amylose content cassava starches obtained from transgenesis comparatively with a natural waxy cassava starch (WXN) discovered recently in CIAT (International Center for Tropical Agriculture). Macromolecular features, starch granule morphology, crystallinity and thermal properties of these starches were determined. M ¯ w of Amylopectin from the transgenic varieties are lower than WXN. Branched and debranched chain distributions analyses revealed slight differences in the branching degree and structure of these Amylopectins, principally on DP 6–9 and DP > 37. For the first time, a deep structural characterization of a series of transgenic lines of waxy cassava was carried out and the link between structural features and the mutated gene expression approached. The transgenesis allows to silenced partially or totally the GBSSI, without changing deeply the starch granule ultrastructure and allows to produce clones with similar Amylopectin as parental cassava clone.
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Molecular and supra-molecular structure of waxy starches developed from cassava (Manihot esculenta Crantz)
Carbohydrate Polymers, 2013Co-Authors: Agnes Sabate, Paul Colonna, Teresa Sanchez, Alain Buleon, Hernan Ceballos, Shanshan Zhao, Peng Zhang, Dominique DufourAbstract:The aim of this work was to characterize the Amylopectin of low amylose content cassava starches obtained from transgenesis comparatively with a natural waxy cassava starch (WXN) discovered recently in CIAT (International Center for Tropical Agriculture). Macromolecular features, starch granule morphology, crystallinity and thermal properties of these starches were determined. (M) over bar (w) of Amylopectin from the transgenic varieties are lower than WXN. Branched and debranched chain distributions analyses revealed slight differences in the branching degree and structure of these Amylopectins, principally on DP 6-9 and DP > 37. For the first time, a deep structural characterization of a series of transgenic lines of waxy cassava was carried out and the link between structural features and the mutated gene expression approached. The transgenesis allows to silenced partially or totally the GBSSI, without changing deeply the starch granule ultrastructure and allows to produce clones with similar Amylopectin as parental cassava clone. (C) 2012 Elsevier Ltd. All rights reserved.
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molecular size and mass distributions of native starches using complementary separation methods asymmetrical flow field flow fractionation a4f and hydrodynamic and size exclusion chromatography hdc sec
Analytical and Bioanalytical Chemistry, 2011Co-Authors: Agnes Rollandsabate, Sophie Guilois, Benoit Jaillais, Paul ColonnaAbstract:Starch consists of a mixture of two α-glucans built mainly upon α-(1,4) linkages: amylose, an essentially linear polymer, and Amylopectin, a branched polymer containing 5–6% of α-(1,6) linkages. The aim of the present work was to analyze the structural properties of native starches displaying different amylose-to-Amylopectin ratios and arising from different botanical sources, using asymmetrical flow field flow fractionation (A4F) and a combination of hydrodynamic and size-exclusion chromatography (HDC-SEC) coupled with multiangle laser light scattering, online quasi-elastic light scattering, and differential refractive index techniques. The procedure, based upon dimethyl sulfoxide pretreatment and then solubilization in water, generates a representative injected sample without altering the initial degree of polymerization. The Amylopectin weight-average molar masses and radii of gyration were around 1.0 × 108–4.8 × 108 g mol-1 and 110–267 nm, respectively. For each starch sample, the hydrodynamic radius (RH) distributions and the molar mass distributions obtained from the two fractionation systems coupled with light scattering techniques were analyzed. The size determination scales were extended by means of RH calibration curves. HDC-SEC and A4F data could be matched. However, A4F enabled a better separation of Amylopectins and therefore an enhanced structural characterization of the starches. The two advantages of this experimental approach are (1) it can directly obtain distributions as a function of both molar mass and size, while taking account of sample heterogeneity, and (2) it is possible to compare the results obtained using the different techniques through the direct application of RH distributions.