Interior of Amylopectin and Nano-Sized Amylopectin Fragments Probed by Viscometry, Dynamic Light Scattering, and Pyrene Excimer Fluorescence

Nano-sized amylopectin fragments (NAFs), prepared by extrusion of waxy corn starch, were investigated by viscometry, dynamic light scattering (DLS), and pyrene excimer fluorescence (PEF). NAF57, with a hydrodynamic diameter of 57 nm, was treated with nitric acid to yield three degraded NAFs, which appeared to share the same interior and structural features as amylopectin based on their measured intrinsic viscosity and hydrodynamic diameter. This conclusion was further supported by comparing the efficiency of forming excimer between an excited and a ground-state pyrenyl label covalently attached to the NAFs (Py-NAFs) using their IE/IM ratio of the fluorescence intensity of the excimer (IE) to that of the monomer (IM). The overlapping trends obtained for all Py-NAFs and the pyrene-labeled amylopectin samples by plotting the IE/IM ratio as a function of pyrene content provided further evidence that the interior of NAFs and amylopectin shared the same structural features and contained a similar amount of free volume as predicted by the Solution-Cluster (Sol-CL) model. The presence of free volume was validated by adding linear poly(ethylene glycol) (PEG) chains that could not penetrate the interior of Py-NAFs, thus subjecting the Py-NAFs to increased osmotic pressure, which induced their compression and resulted in an increase in IE/IM.

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Structural Features and Digestibility of Corn Starch With Different Amylose Content

Frontiers in Nutrition ◽

10.3389/fnut.2021.692673 ◽

2021 ◽

Vol 8 ◽

Author(s):

Xinxin Lv ◽

Yan Hong ◽

Qiwei Zhou ◽

Chengchen Jiang

Keyword(s):

Crystalline Structure ◽

Corn Starch ◽

Amylose Content ◽

Structural Features ◽

Particle Structure ◽

Scanning Calorimetry ◽

Short Branch ◽

Waxy Corn Starch ◽

Waxy Corn

In this study, the in vitro digestibility of corn starch with different amylose content was determined. The results showed that waxy corn starch (WCS) and corn starch (CS) have the highest digestibility, while high amylose corn starch (HACS) has a higher content of resistant starch (RS). Besides being related to amylose content, RS content is also closely related to particle shape, debranched fine structure, molecular structure, and semi-crystalline structure. HACS can maintain a complete particle structure after gelatinization and enzymolysis; differential scanning calorimetry showed a positive correlation between gelatinization enthalpy and RS content. As the amylose content increased, the content of fa (DP 6–12) decreased, while the content of fb2 (DP 25–36) and fb3 (DP ≥ 37) increased, which in-turn decreased the cluster polymer formed by short branch chains, and the formation of more hydrogen bonds between long chain branches improved starch stability. D, which characterizes the compactness of starch semi-crystalline structure, increased with the increase of RS content. HACS 60 with the highest RS content had a unique surface fractal structure between 7.41 < d (2π/q) < 10.58 nm, indicating that the dense structure is effective in maintaining the RS content.

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Characterization of Normal and Waxy Corn Starch for Bioethanol Production

Journal of Agricultural and Food Chemistry ◽

10.1021/jf305100n ◽

2013 ◽

Vol 61 (2) ◽

pp. 379-386 ◽

Cited By ~ 25

Author(s):

Hanyu Yangcheng ◽

Hongxin Jiang ◽

Michael Blanco ◽

Jay-lin Jane

Keyword(s):

Corn Starch ◽

Bioethanol Production ◽

Waxy Corn Starch ◽

Waxy Corn

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A simple and sensitive sensor for silver ions based on unmodified gold nanoparticles by using dynamic light scattering techniques

Canadian Journal of Chemistry ◽

10.1139/cjc-2017-0241 ◽

2017 ◽

Vol 95 (12) ◽

pp. 1267-1272 ◽

Cited By ~ 3

Author(s):

Zhiyou Xiao ◽

Anjiang Tang ◽

Hongsheng Huang ◽

Ze Wang

Keyword(s):

Gold Nanoparticles ◽

Light Scattering ◽

Dynamic Light Scattering ◽

High Sensitivity ◽

Silver Ions ◽

Hydrodynamic Diameter ◽

Optimum Conditions ◽

Sensitivity And Selectivity ◽

Sensitive Sensor ◽

Average Hydrodynamic Diameter

A simple and sensitive assay for Ag+ was developed with unmodified gold nanoparticles (AuNPs) by using dynamic light scattering techniques. Ag+ could induce the oligonucleotide (5′-ATC ACT ATA TCA TAT ACT CAT-3′) to change from a single-stranded structure to a double-stranded structure and desorb from the surface of AuNPs, which triggered the aggregation of AuNPs in the salt solution. The average hydrodynamic diameter of aggregated AuNPs could be detected by using dynamic light scattering techniques. Under the optimum conditions, the average hydrodynamic diameter of AuNPs is proportional to the concentration of Ag+ within the range of 13.3–100.0 nmol/L, with a detection limit of 3.2 nmol/L. The method is easy to operate and has low sample consumption, high sensitivity and selectivity.

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Effect of multi-mode dual-frequency ultrasound irradiation on the degradation of waxy corn starch in a gelatinized state

Food Hydrocolloids ◽

10.1016/j.foodhyd.2020.106440 ◽

2020 ◽

pp. 106440

Author(s):

Baoguo Xu ◽

Aiqing Ren ◽

Jianan Chen ◽

Hongyan Li ◽

Benxi Wei ◽

...

Keyword(s):

Corn Starch ◽

Ultrasound Irradiation ◽

Dual Frequency ◽

Waxy Corn Starch ◽

Waxy Corn ◽

Multi Mode ◽

Frequency Ultrasound

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COMPLEXATION OF POLYETHYLENE-GLYCOL WITH THE SODIUM SALTS OF CITRIC AND SUCCINIC ACIDS IN THE AQUEOUS SOLUTIONS. STUDIES BY DYNAMIC LIGHT SCATTERING AND UV/VIS SPECTROPHOTOMETRY

JOURNAL OF ADVANCES IN CHEMISTRY ◽

10.24297/jac.v11i8.2192 ◽

2015 ◽

Vol 11 (8) ◽

pp. 3866-3872

Author(s):

E.A. Masimov ◽

Etibar Hummat Ismailov ◽

S.Y. Odzhaqverdiyeva

Keyword(s):

Molecular Weight ◽

Light Scattering ◽

Dynamic Light Scattering ◽

Aqueous Solutions ◽

Polyethylene Glycols ◽

Hydrodynamic Diameter ◽

Absorption Bands ◽

Sodium Salts ◽

And Diffusion ◽

Formation Of Complexes

Dynamic light scattering (DLS) method in combination with the UV/VIS spectrophotometry is used to study the interaction of polyethylene- glycols with a molecular weight 6000 ( PEG6000 ) with sodium salts of citric and succinic acids in aqueous solutions. The values of density, viscosity, refractive and diffusion indexes, the values of the hydrodynamic diameter, wavelength electronic absorption bands for PEG6000 aqueous solutions, their mixtures with succinic and citric acids are determined. It was shown that depending on the composition of the solutions the values of hydrodynamic diameter for aqueous solutions containing 1-5 wt.% PEG6000 and their mixtures with succinic and citric acids (~ 1 wt%) ranges from 3.6 to 5.2 nm. It is assumed that the formation of complexes with the sizes that are within the above range is due to the features of interaction and the structure of the complexes formed in solution.

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