Architecture of outer shell and inner blocklets of rice starch granule is related to starch granule-associated proteins. (June 2022)

• Record Type: Journal Article
• Authors: Ma, Mengting; Xu, Zekun; Chen, Xiaojing; Zhang, Chuangchuang; Liu, Ziyi; Cantre, Dennis; Li, Haitao; Sui, Zhongquan; Corke, Harold
• Is Part Of: Food hydrocolloids. Volume 127(2022)
• Publication Date: 2022-06
• Subjects: Rice starch -- Outer shell -- Inner blocklets -- Amylopectin -- Starch granule-associated proteins -- Starch synthesis enzymes; SGAPs Starch granule-associated proteins -- WRS Waxy rice starch -- LARS Low-amylose rice starch -- HARS High-amylose rice starch -- WRS-I Inner blocklets of waxy rice starch -- LARS-I Inner blocklets of low-amylose rice starch -- HARS-I Inner blocklets of high-amylose rice starch -- WRS-O Outer shell of waxy rice starch -- LARS-O Outer shell of low-amylose rice starch -- HARS-O Outer shell of high-amylose rice starch -- SEM Scanning electron microscopy -- CLSM Confocal laser scanning microscopy -- APTS 8-aminopyrene-1, 3, 6, trisulfonic acid -- SDS-PAGE Sodium dodecyl sulfate polyacrylamide gel electrophoresis -- SS Starch synthase -- SSS Soluble starch synthase -- GBSS Granule-bound starch synthase -- SBE Starch branching enzymes -- DBE Starch debranching enzymes -- AGPase ADP-glucose pyrophosphorylase; Hydrocolloids -- Periodicals; Food additives -- Periodicals; Colloïdes -- Périodiques; Aliments -- Additifs -- Périodiques; Colloids; Food additives; Periodicals; Electronic journals; 664.06
• DOI: 10.1016/j.foodhyd.2022.107551
• Languages: English
• ISSNs: 0268-005X

Abstract

Abstract: Waxy, low-amylose and high-amylose rice starches were chosen to separate inner blocklets and outer shell from their granules under incomplete gelatinization. Isolated outer shells and swollen or merged inner blocklets, based on morphological structure of broken granules, were used as a probe to study the mechanism of differences between outer and inner blocklets formation, through molecular characteristics and starch granule-associated proteins (SGAPs) analyses. On the basis of molecular composition, it was concluded that shorter branched-chain amylopectin and some amylose chains were involved in the formation of inner blocklets (shells). While the stronger interaction occurred among outer blocklets (shell), those are composed of longer branched-chains amylopectin and few amylose molecules. SGAPs types and content of inner shells (blocklets) were higher than outer shell (blocklets). SGAPs not only interacted with amylose chains but also with amylopectin chains. The enzymatic machinery for biosynthesis, such as starch branching enzyme, plays a critical role in blocklet architecture. Graphical abstract: Image 1 Highlights: Inner blocklets and outer shell were successfully separated from rice starch granules. Inner blocklets are mainly composed of shorter amylopectin and some amylose chains. Longer amylopectin and few amylose chains are involved in formation of outer shell. SGAP types and content of inner blocklets were higher than for outer shell. Starch synthesis enzymes play a critical role in blocklet architecture.