Effect of drought stress on the morphological and physicochemical properties of starches from Trimezia juncifolia

Viviane O Almeida; Karla A Batista; Maria C B Di-Medeiros; Moemy G Moraes; Kátia F Fernandes

doi:10.1016/j.carbpol.2019.02.015

Effect of drought stress on the morphological and physicochemical properties of starches from Trimezia juncifolia

Carbohydr Polym. 2019 May 15:212:304-311. doi: 10.1016/j.carbpol.2019.02.015. Epub 2019 Feb 6.

Authors

Viviane O Almeida¹, Karla A Batista², Maria C B Di-Medeiros¹, Moemy G Moraes³, Kátia F Fernandes⁴

Affiliations

¹ Laboratório de Química de Polímeros, Instituto de Ciências Biológicas, ICB 2, Universidade Federal de Goiás, Goiânia, GO, Brazil.
² Laboratório de Química de Polímeros, Instituto de Ciências Biológicas, ICB 2, Universidade Federal de Goiás, Goiânia, GO, Brazil; Departamento de Áreas Acadêmicas, Instituto Federal de Educação, Ciência e Tecnologia de Goiás, Campus Goiânia Oeste, Goiânia, GO, Brazil.
³ Laboratório de Fisiologia Vegetal, Instituto de Ciências Biológicas, ICB 1, Universidade Federal de Goiás, Goiânia, GO, Brazil.
⁴ Laboratório de Química de Polímeros, Instituto de Ciências Biológicas, ICB 2, Universidade Federal de Goiás, Goiânia, GO, Brazil. Electronic address: kfernandes.lqp@gmail.com.

PMID: 30832862
DOI: 10.1016/j.carbpol.2019.02.015

Abstract

In this study corms from Trimezia juncifolia were collected in the wet (WSS) and dry (DSS) seasons and used for extraction of starch. Results evidenced that drought stress interfered with the yield, morphological and physicochemical properties of the starches. In addition, it was observed a higher content of amylose for DSS (44%) when compared with WSS (41%). Drought stress did not interfere with the degree of polymerization (DP) of amylopectin, whereas decreased the amylose DP for DSS. Also, starch granules changed from A-type polymorph in the DSS to a C_C-type in WSS. Drought stress reduced the starch crystallinity from 27% in WSS to 25.9% in DSS. In addition, the endothermic transition temperatures and enthalpy change of transition were also affected by drought stress. Finally, results clearly demonstrate that changes in the morphological and physicochemical properties of the starch granules figure as adaptive strategies of T. junciolia to drought stress.

Keywords: Amylopectin; Amylose; Cataphylls; Drought stress.