scholarly journals V-type crystal formation in starch by aqueous ethanol treatment: The effect of amylose degree of polymerization

2016 ◽  
Vol 61 ◽  
pp. 649-661 ◽  
Author(s):  
D.M. Dries ◽  
S.V. Gomand ◽  
J.A. Delcour ◽  
B. Goderis
Keyword(s):  
Aqueous Ethanol ◽  
Degree Of Polymerization ◽  
Crystal Formation ◽  
Ethanol Treatment ◽  
Type Crystal

scholarly journals Hierarchical Structure, Gelatinization, and Digestion Characteristics of Starch from Longan (Dimocarpus longan Lour.) Seeds

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3262
Author(s):  
Ziman Hu ◽  
Lei Zhao ◽  
Zhuoyan Hu ◽  
Kai Wang
Keyword(s):  
Amylose Content ◽  
Level Structure ◽  
Degree Of Polymerization ◽  
Raw Starch ◽  
Relative Crystallinity ◽  
Digestion Process ◽  
Gelatinized Starch ◽  
Multi Level ◽  
Longan Seed ◽  
Type Crystal

Starch was isolated from longan seeds of three widely distributed cultivars (Chuliang, Shixia, and Caopu) in China. Comparisons of the multi-level structure of the starch of longan seeds among various cultivars were made, and the relations between these structural and property characteristics are discussed. The isolated starch, accounting for 44.9–49.5% (w/w) in longan seeds, had an oval or an irregular polygonal shape with a smooth surface. Their chain-length distributions (CLDs) varied with longan cultivar; Chuliang showed a larger proportion of longer amylopectin chains with a degree of polymerization (DP) 30~100. This is attributed to the slightly higher relative crystallinity of Chuliang longan seed starch. Apparent differences were also detected in amylose structure. Caopu showed a higher amylose content than Chuliang and Shixia, resulting in its lower gelatinization temperatures and enthalpy change. All longan seed starch had a typical A-type crystal structure with relative crystallinity ranging 28.6–28.9%. For raw starch, Caopu showed the lowest digestion rate, followed by Chuliang; Shixia showed the highest. This is because Caopu had the highest amylose content. Chuliang had a more intact structure than Shixia, as suggested by its higher crystallinity, although they had similar amylose content. After being fully gelatinized, all starch showed a similar digestion process, indicating that the digestibility of gelatinized starch does not differ with starch source or structure.

scholarly journals Linear Dextrin as Potential Insulin Delivery System: Effect of Degree of Polymerization on the Physicochemical Properties of Linear Dextrin–Insulin Inclusion Complexes

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4187
Author(s):  
Huifang Xie ◽  
Xin Ma ◽  
Wenbin Lin ◽  
Shiting Dong ◽  
Qiang Liu ◽  
...  
Keyword(s):  
Inclusion Complexes ◽  
Aqueous Ethanol ◽  
Potato Starch ◽  
Degree Of Polymerization ◽  
X Ray Diffraction ◽  
System Effect ◽  
X Ray ◽  
Ft Ir ◽  
Ir Analysis ◽  
Differential Solubility

In the current study, linear dextrin (LD) was prepared using waxy potato starch debranched with pullulanase, which has attracted immense interest in the food, pharmaceutical, and cosmetic industries as a versatile ingredient. Various LDs were separated on the basis of their differential solubility in aqueous/ethanol solutions of different volumetric ratios. Three LD products—LD Fabrications with 40% ethanol (F-40); LD Fabrications with 50% ethanol (F-50); and LD Fabrications with 60%, 70%, and 80% ethanol (F-M)—were obtained with an average degree of polymerization (DP) values of 31.44, 21.84, and 16.10, respectively. The results of Fourier transform infrared spectroscopy (FT-IR) analysis revealed that the reaction mainly involved hydrogen bonding and a hydrophobic interaction between LD and insulin in the process of inclusion complex formation. X-ray diffraction (XRD) results indicated that insulin was encapsulated in LD. The results of circular dichroism (CD) showed that the changes in the secondary structure of insulin were negligible during the release from the inclusion complexes. The order of encapsulation capacity is as follows: the complex composed of F-M and insulin (F-M-INS) > the complex composed of LD and insulin (LD-INS) > the complex composed of F-50 and insulin (F-50-INS) > and the complex composed of F-40 and insulin (F-40-INS). F-M-INS inclusion complexes showed a better effect on reducing the release of insulin in gastric juice and promoting the release of insulin in intestinal juice and blood plasma than LD-INS.

Controlling molecular conformation of regenerated wild silk fibroin by aqueous ethanol treatment

2003 ◽  
Vol 14 (10) ◽  
pp. 694-698 ◽  
Author(s):  
Mingzhong Li ◽  
Wei Tao ◽  
Shigenori Kuga ◽  
Yoshiharu Nishiyama
Keyword(s):  
Silk Fibroin ◽  
Molecular Conformation ◽  
Aqueous Ethanol ◽  
Ethanol Treatment

scholarly journals Enhanced cellulose degradation of wheat straw during aqueous ethanol organosolv treatment

BioResources ◽  
2017 ◽  
Vol 12 (4) ◽  
pp. 9407-9419
Author(s):  
Martin Lindemann ◽  
Anton Friedl ◽  
Ewald Srebotnik
Keyword(s):  
Wheat Straw ◽  
High Performance ◽  
Aqueous Ethanol ◽  
Cellulose Degradation ◽  
Fiber Quality ◽  
Degree Of Polymerization ◽  
Size Exclusion ◽  
Free Form ◽  
Cellulose Pulp ◽  
Water Ratio

The degradation of cellulose in wheat straw during aqueous ethanol organosolv (AEO) treatment under different pulping conditions was investigated. For this purpose, molecular weight distribution (MWD) and degree of polymerization (DP) of the resulting cellulose pulp were determined using high performance size exclusion chromatography (HPSEC). The most pronounced effects regarding cellulose degradation were observed when varying the ethanol-to-water ratio. UV detection in HPSEC indicated that residual lignin in wheat straw fibers from organosolv treatments does not occur in free form, but rather is associated with hemicellulose (xylan) and to a minor extent also with cellulose. The established method was suitable for relative comparisons of MWD of variously treated wheat straw fibers and hence for obtaining information regarding the severity of organosolv treatment in terms of cellulose degradation. In summary, AEO treatment at a low ethanol-to-water ratio favours the efficient delignification and removal of xylan from wheat straw, but this occurs at the price of a greatly reduced fiber quality in terms of DP.

The Critical Point Drying Method Applied to Scanning Electron Microscopy of L-929 Cells

1970 ◽  
Vol 28 ◽  
pp. 278-279
Author(s):  
Charles TurnbiLL ◽  
Delbert E. Philpott
Keyword(s):  
Electron Microscopy ◽  
Carbon Dioxide ◽  
Surface Tension ◽  
Critical Point ◽  
Freeze Drying ◽  
Attractive Alternative ◽  
Crystal Formation ◽  
Critical Point Drying ◽  
Time Required ◽  
Scanning Electron

The advent of the scanning electron microscope (SCEM) has renewed interest in preparing specimens by avoiding the forces of surface tension. The present method of freeze drying by Boyde and Barger (1969) and Small and Marszalek (1969) does prevent surface tension but ice crystal formation and time required for pumping out the specimen to dryness has discouraged us. We believe an attractive alternative to freeze drying is the critical point method originated by Anderson (1951; for electron microscopy. He avoided surface tension effects during drying by first exchanging the specimen water with alcohol, amy L acetate and then with carbon dioxide. He then selected a specific temperature (36.5°C) and pressure (72 Atm.) at which carbon dioxide would pass from the liquid to the gaseous phase without the effect of surface tension This combination of temperature and, pressure is known as the "critical point" of the Liquid.

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