Effects of HMW-GS Dx2 absence on the protein aggregation characteristics and thermal stability of wheat flour during maturation  

作　　者：Liye Zhao Lijun Song Liqun Li Xuejun Li 

机构地区：[1]StateKey Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy,Northwest A&F University,Yangling,China [2]Biotechnology Branch,Xinjiang Agricultural Vocational Technical College,Changji,China [3]College of Horticulture,State Key Laboratory of North China Crop Improvement and Regulation,Hebei Agricultural University,Baoding,China

出　　处：《Food Quality and Safety》2023年第2期338-347,共10页食品品质与安全研究（英文版）

基　　金：supported by the Key Science and Technology Project of Shaanxi Agricultural Collaborative Innovation and Extension Alliance(No.LMZD202104);the Introduction of Talents for Scientific Research of State Key Laboratory of North China Crop Improvement and Regulation(No.NCCIR2020RC-11).

摘　　要：Background:Wheat flour maturation affects the aggregation and structural stability of proteins.The number of high-molecular-weight glutenin subunits(HMW-GSs)differs in various wheat varieties.The effects of Dx2 absence on the protein aggregation characteristics and thermal sta-bility of flour were investigated during 120 d of maturation using near-isogenic lines(NILs).Results:The absence of Dx2 delayed and decreased the protein aggregation of flours during maturation,i.e.the maturation-induced increases were later and smaller for glutenin,glutenin macropolymer(GMP),glutenin/gliadin ratio,β-sheets,andβ-sheet/a-helix ratio in HMW-D1a without Dx2 than in HMW-D1p with Dx2;these differences were ascribed to the weaker interactions between the sulfhydryl(-SH)groups,disulfide bonds(-S-S-),and hydrophobicity in the flours without Dx2.Flour maturation caused the dough microstructures to be more compact and denser,thereby increasing the flour thermal stability as observed by a higher denaturation peak temperature(Tp),enthalpy of thermal transition(△H),and degradation temperature(Td),These changes led to better dough properties such as dough development time,dough stability time,and protein weakening,but the optimal stage in HMW-D1a without Dx2was reached later.Conclusion:These findings deepen the understanding of how HMW-GS Dx2 modifies protein structures during flour maturation.

关 键 词：Dx2 absence disulfide bond glutenin macropolymer secondary and micro structures thermal stability wheat flour maturation 

分 类 号：TS210.1[轻工技术与工程—粮食、油脂及植物蛋白工程]