Facile and efficient chemical synthesis of gluco-oligosaccharides (GlcOS) with diverse glycosidic linkages as potential prebiotics to promote the growth of probiotic bacteria. (March 2023)

• Record Type: Journal Article
• Authors: Zeng, Meijun; Li, Ning; Astmann, Theresa; Oh, Jee-Hwan; van Pijkeren, Jan-Peter; Pan, Xuejun
• Is Part Of: Food research international. Volume 165(2023)
• Publication Date: 2023-03
• Subjects: Non-digestible oligosaccharides -- Dehydration condensation -- Glycosylation -- In vitro fermentation -- Isomalto-oligosaccharides; GlcOS gluco-oligosaccharides -- IMOs isomalto-oligosaccharides -- HPAEC-PAD high-performance anion-exchange chromatography with pulsed amperometric detection -- TLC thin-layer chromatography -- MALDI-TOF MS matrix-assisted laser desorption/ionization-time of flight mass spectrometry -- DP degree of polymerization -- NMR nuclear magnetic resonance; Food -- Analysis -- Periodicals; Food industry and trade -- Periodicals; Food industry and trade -- Canada -- Periodicals; Food Technology -- Periodicals; Food -- Periodicals; Food-Processing Industry -- Periodicals; Aliments -- Industrie et commerce -- Périodiques; Aliments -- Industrie et commerce -- Canada -- Périodiques; Aliments -- Recherche -- Périodiques; Food industry and trade; Canada; Periodicals; Electronic journals; 664.005
• DOI: 10.1016/j.foodres.2022.112436
• Languages: English
• ISSNs: 0963-9969

Abstract

Graphical abstract: Highlights: A facile method was developed to synthesize gluco-oligosaccharides (GlcOS) Low-cost and abundant H2 SO4 solution was used as a medium for GlcOS synthesis. The GlcOS synthesis was conducted under mild conditions with a high yield of 83% The synthesized GlcOS had a DP of 2–9 with diverse glycosidic linkages. The prebiotic activity of GlcOS was verified by select probiotic bacteria in vitro. Abstract: Glucose-based short-chain oligosaccharides (gluco-oligosaccharides, GlcOS) have been established as functional food ingredients with health-promoting properties. Currently, GlcOS (e.g., isomalto-oligosaccharides, IMOs) are commercially produced via enzymatic processes, which face the challenges of low yield and high cost. Therefore, developing efficient technologies for large-scale production of prebiotic GlcOS is highly desirable. Herein, a facile chemical process was developed to synthesize GlcOS as potential prebiotics via enhanced dehydration condensation of glucose in concentrated sulfuric acid (60–92 %). The maximum GlcOS yield of 83 % was achieved under the optimal condition of 50 % initial glucose loading, 76 % H2 SO4, 70 °C, and 20 min. Structural analysis revealed that the synthesized GlcOS are mainly short-chain oligomers with a degree of polymerization (DP) between 2 and 4 (46 % DP 2, 22 % DP 3, 12 % DP 4) and a small percentage of larger oligosaccharides (DP 5–9), which are linked by predominantly α- and β-(1→6) linkages along with (1→4), (1→ 3), (1→2), and (1↔1) linkages. In vitro fermentation experiments by probiotic Bifidobacterium bifidum ATCC 29521, Bifidobacterium animalis subsp. lactis DSM 10140, and Limosilactobacillus reuteri ATCC 6475 indicated that the GlcOS can be utilized as a carbon source for bacterial growth, and their promotion effect was overall comparable to three commercial prebiotic IMOs. GlcOS were also successfully synthesized from maltose and cellobiose with similar yield and structures to those from glucose, implying the possibility of synthesizing the prebiotic GlcOS directly from inexpensive starch and cellulose.