Structural characterization of a novel mannogalactoglucan from Fortunella margarita and its simulated digestion in vitro

• Published in: Food and chemical toxicology 2019-11, Vol.133, p.110778-110778, Article 110778
• Main Authors: Chen, Peilin, Lin, Yan, Chen, Yueyu, Chang, Qing, Zheng, Baodong, Zhang, Yi, Hu, Xiaoke, Zeng, Hongliang
• Format: Article
• Language: English
• Subjects: Carbohydrate Sequence; Digestion; Fortunella margarita; Galactans - chemistry; Gastric Juice - chemistry; Glucans - chemistry; Hydrolysis; Intestinal Secretions - chemistry; Mannogalactoglucan; Mannose - chemistry; Molecular Weight; Polysaccharide fraction; Rutaceae - chemistry; Saliva - chemistry; Simulated digestion; Structural characterization
• ISSN: 0278-6915; 1873-6351
• DOI: 10.1016/j.fct.2019.110778

This study was to investigate the structure of a polysaccharide fraction from the Fortunella margarita and the relationship between its digestibility and structure. A novel polysaccharide fraction extracted by graded precipitation at ethanol concentrations of 20% from F. margarita (named FP20) comprised mainly glucose, galactose, and mannose. The unit composition was →4)-β-Glcp-(1 → 2)-α-Glcp-(1 → 2)-α-Galp-(1 → 4)-α-Galp-(1→ bone, and in →2)-α-Galp-(1→) with a branching point at C6 of β-Manp. FP20 was identified as a mannogalactoglucan with a different monosaccharide composition ratio and side-chain sugar residues compared with other plant polysaccharides. Moreover, FP20 had a spherical aggregations by atomic force microscope test. FP20 had an island-shaped structures with a smooth surface revealed by field emission scanning electron microscopy. Furthermore, in vitro digestive test, FP20 was resistance to a digestion system of saliva-gastric-small intestinal. The digestibility of FP20 was related to its backbone unit, structure and tight, uniform, and spherical chain conformation in aqueous. [Display omitted] •FP20 was a novel mannogalactoglucan.•FP20 had special monosaccharide composition ratios and side-chains.•FP20 resisted to saliva-gastric and saliva-gastric-small intestinal digestion.•The digestibility of FP20 was related to its special structure.