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bioRxiv · 10.1101/2023.03.10.532015

Unusual starch grains from the Euphorbia caducifolia Haines

KUSUMA, V.·Kottapalli, S.
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Abstract

Nature has chosen the starch as a universal form for storing carbohydrate. In granule form, it is semi-crystalline, water-insoluble, dense and a ubiquitous constituent. Structure of the starch granules depends on their biological source and varies from part to part of the sources. In sequence to that, starch granules from the latex of Euphorbia caducifolia was isolated and characterized under different conditions to reveal its uniqueness in the structure. A flat dumbbell-shaped starch was notified with distinctive "maltese cross" under various microscopes. These starches are found to be high amylose contents, which resist water solubility, swelling index, and turbidity of the starches. X-Ray Diffraction studies states the presence C type pattern of crystallinity whereas typical polysaccharide spectrum was observed with ATR studies. Gelatinization of the starches remarked them as highly thermal stable and retrogradation studies failed to detect realignment of the heat disrupted amylose and amylopectin. Lintnerization of starch granules reveals the high complexity of the structure. Thus, latex starch granules from the E caducifolia are considered to be unusual because of their highly complex structure, shape and properties.

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KUSUMA, V., Kottapalli, S.. 2023-03-11. Unusual starch grains from the Euphorbia caducifolia Haines. https://doi.org/10.1101/2023.03.10.532015

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