Date of Award
12-5-2018
Document Type
Thesis
Degree Name
Biology, MS
First Advisor
Brett Savary
Committee Members
Fabricio Medina-Bolivar; Jianfeng (Jay) Xu
Call Number
LD 251 .A566t 2018 T35
Abstract
Increased consumption of soluble cereal arabinoxylan (AX), and feruloylated arabinoxylan oligosaccharides (FAXOs) generated from it, may promote healthful gastro-intestinal functioning through modulating the gut microbiota and tuning innate immune response function at the gut epithelium. FAXO compositions isolated from rice bran fiber were characterized for their oligosaccharide mass profiles (MALDI-TOF MS) and monosaccharide compositions (GC-FID). Results indicated gluco-oligosaccharides were covalently associated with the FAXOs. I tested the hypothesis that the association represents a novel intermolecular crosslink between mixed linkage β-glucan and AX in rice caryopsis cell walls. The structural characteristics of gluco-oligosaccharides were analyzed to determine glycosidic linkages (GC-MS) and anomeric configuration (anomer-specific glucosidase digestion). Results confirmed glucan structures are covalently coupled to feruloylated arabinose but are composed of linear (1α →4) linkages. This unexpected result indicates the gluco-oligosaccharides are derived from starch. We propose such α-glucan crosslinks formed through an enzymatic transglycosylation reaction that occurred during bran fiber preparation.
Rights Management
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Takahashi, Kan, "Structural characterization of feruloylated arabinoxylan oligosaccharides isolated from rice bran fiber" (2018). Student Theses and Dissertations. 465.
https://arch.astate.edu/all-etd/465
