Structural and chemical characterization of rice and potato starch granules using microscopy and spectroscopy

Abstract In maize plant breeding aimed at producing a hybrid, it is necessary to characterize the parents and hybrids by their agronomic aspects and grain quality so that the processing industry may offer consumers a quality product and also improve its efficiency. This study evaluated the viscoelastic parameters of masa and the chemical and texture properties of tortillas obtained from parent lines (M-54, M55, and CML-242), two single crosses (M54xM55 and M55xM54), and one hybrid (H-70). The morphology of the maize grains and tortillas was analyzed using scanning electron microscopy. The firmness of masa obtained from CML-242 and H-70 maize was higher than that from the other maize genotypes. M-54 tortillas showed the lowest crude fiber content. Otherwise, tortillas obtained from the M55xM54 hard grain had the lowest fat content and extensibility, while H-70 tortillas showed an intermediate breaking point and extensibility. M-54 and M54xM55 tortillas were softer due to their more swollen starch granules. In contrast, rigid tortillas were obtained from CML-242 and H-70. Grain hardness causes different morphology in starch and tortilla of maize genotypes. However, grain hardness did not influence the characteristics of texture in tortillas.

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Molecular and physico-chemical characterization of de-structured waxy potato starch

Food Hydrocolloids ◽

10.1016/j.foodhyd.2021.106667 ◽

2021 ◽

Vol 117 ◽

pp. 106667

Author(s):

Cai Ling Ang ◽

Lara Matia-Merino ◽

Kaiyang Lim ◽

Kelvin Kim Tha Goh

Keyword(s):

Potato Starch ◽

Chemical Characterization ◽

Physico Chemical

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Degradation of Granular Starch by the Bacterium Microbacterium aurum Strain B8.A Involves a Modular α-Amylase Enzyme System with FNIII and CBM25 Domains

Applied and Environmental Microbiology ◽

10.1128/aem.01029-15 ◽

2015 ◽

Vol 81 (19) ◽

pp. 6610-6620 ◽

Cited By ~ 18

Author(s):

Vincent Valk ◽

Wieger Eeuwema ◽

Fean D. Sarian ◽

Rachel M. van der Kaaij ◽

Lubbert Dijkhuizen

Keyword(s):

Enzyme System ◽

Recombinant Expression ◽

Potato Starch ◽

Carbohydrate Binding ◽

Starch Granules ◽

Catalytic Core ◽

Content Type ◽

C Terminus ◽

Carbohydrate Binding Modules

ABSTRACTThe bacteriumMicrobacterium aurumstrain B8.A, originally isolated from a potato plant wastewater facility, is able to degrade different types of starch granules. Here we report the characterization of an unusually large, multidomainM. aurumB8.A α-amylase enzyme (MaAmyA). MaAmyA is a 1,417-amino-acid (aa) protein with a predicted molecular mass of 148 kDa. Sequence analysis of MaAmyA showed that its catalytic core is a family GH13_32 α-amylase with the typical ABC domain structure, followed by a fibronectin (FNIII) domain, two carbohydrate binding modules (CBM25), and another three FNIII domains. Recombinant expression and purification yielded an enzyme with the ability to degrade wheat and potato starch granules by introducing pores. Characterization of various truncated mutants of MaAmyA revealed a direct relationship between the presence of CBM25 domains and the ability of MaAmyA to form pores in starch granules, while the FNIII domains most likely function as stable linkers. At the C terminus, MaAmyA carries a 300-aa domain which is uniquely associated with large multidomain amylases; its function remains to be elucidated. We concluded thatM. aurumB8.A employs a multidomain enzyme system to initiate degradation of starch granules via pore formation.

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Chemical Characterization of Bromine Oxidized Potato Starch

Starch - Stärke ◽

10.1002/star.19900421102 ◽

1990 ◽

Vol 42 (11) ◽

pp. 413-417 ◽

Cited By ~ 26

Author(s):

Liz J. Torneport ◽

B. Ann Christine Salomonsson ◽

Olof Theander

Keyword(s):

Potato Starch ◽

Chemical Characterization

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Intra-Sample Heterogeneity of Potato Starch Reveals Fluctuation of Starch-Binding Proteins According to Granule Morphology

Plants ◽

10.3390/plants8090324 ◽

2019 ◽

Vol 8 (9) ◽

pp. 324

Author(s):

Stanislas Helle ◽

Fabrice Bray ◽

Jean-Luc Putaux ◽

Jérémy Verbeke ◽

Stéphanie Flament ◽

...

Keyword(s):

Starch Granule ◽

Potato Starch ◽

Granule Size ◽

Starch Granules ◽

Label Free ◽

Granule Morphology ◽

Sample Heterogeneity ◽

Amylopectin Structure ◽

Unimodal Pattern

Starch granule morphology is highly variable depending on the botanical origin. Moreover, all investigated plant species display intra-tissular variability of granule size. In potato tubers, the size distribution of starch granules follows a unimodal pattern with diameters ranging from 5 to 100 µm. Several evidences indicate that granule morphology in plants is related to the complex starch metabolic pathway. However, the intra-sample variability of starch-binding metabolic proteins remains unknown. Here, we report on the molecular characterization of size-fractionated potato starch granules with average diameters of 14.2 ± 3.7 µm, 24.5 ± 6.5 µm, 47.7 ± 12.8 µm, and 61.8 ± 17.4 µm. In addition to changes in the phosphate contents as well as small differences in the amylopectin structure, we found that the starch-binding protein stoichiometry varies significantly according to granule size. Label-free quantitative proteomics of each granule fraction revealed that individual proteins can be grouped according to four distinct abundance patterns. This study corroborates that the starch proteome may influence starch granule growth and architecture and opens up new perspectives in understanding the dynamics of starch biosynthesis.

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Chemical characterization of dextrins obtained from potato starch by treatment with Bacillus macerans enzyme

Journal of Fermentation and Bioengineering ◽

10.1016/0922-338x(89)90207-9 ◽

1989 ◽

Vol 68 (1) ◽

pp. 14-18 ◽

Cited By ~ 1

Author(s):

Yoji Kato ◽

Junko Nomura ◽

Katsuhiko Mikuni ◽

Kozo Hara ◽

Hitoshi Hashimoto ◽

...

Keyword(s):

Potato Starch ◽

Chemical Characterization ◽

Bacillus Macerans

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An Electron Diffraction Study on Litnerized Potato Starch

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010018166x ◽

1990 ◽

Vol 48 (1) ◽

pp. 580-581

Author(s):

Jean-Claude Jésior ◽

Roger Vuong ◽

Henri Chanzy

Keyword(s):

Electron Microscope ◽

Electron Diffraction ◽

Signal To Noise Ratio ◽

Potato Starch ◽

Image Intensifier ◽

Electron Diffraction Study ◽

Starch Granules ◽

X Ray ◽

Individual Grains ◽

Diamond Knife

Starch is arranged in a crystalline manner within its storage granules and should thus give sharp X-ray diagrams. Unfortunately most of the common starch granules have sizes between 1 and 100μm, making them too small for an X-ray study on individual grains. There is only one instance where an oriented X-ray diagram could be obtained on one sector of an individual giant starch granule. Despite their small size, starch granules are still too thick to be studied by electron diffraction with a transmission electron microscope. The only reported study on starch ultrastructure using electron diffraction on frozen hydrated material was made on small fragments. The present study has been realized on thin sectioned granules previously litnerized to improve the signal to noise ratio.Potato starch was hydrolyzed for 10 days in 2.2N HCl at 35°C, dialyzed against water until neutrality and embedded in Nanoplast. Sectioning was achieved with a commercially available low-angle “35°” diamond knife (Diatome) after a very carefull trimming and a pre-sectioning with a classical “45°” diamond knife. Sections obtained at a final sectioning angle of 42.2° (compared with the usual 55-60°) and at a nominal thickness of 900Å were collected on a Formvar-carbon coated grid. The exact location of the starch granules in their sections was recorded by optical microscopy on a Zeiss Universal polarizing microscope (Fig. 1a). After rehydration at a relative humidity of 95% for 24 hours they were mounted on a Philips cryoholder and quench frozen in liquid nitrogen before being inserted under frozen conditions in a Philips EM 400T electron microscope equipped with a Gatan anticontaminator and a Lhesa image intensifier.

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