Structural diversity and prebiotic potential of short chain β-manno-oligosaccharides generated from guar gum by endo-β-mannanase (ManB-1601)

• Published in: Carbohydrate research Vol. 486; p. 107822
• Main Authors: Mary, Priyanka Rose, Prashanth, K.V. Harish, Vasu, Prasanna, Kapoor, Mukesh
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.12.2019
• Subjects: Bacteria - metabolism; beta-Mannosidase - metabolism; Endo-mannanase; Enteropathogens; Fermentation; Galactans - chemistry; Guar gum; Hydrolysis; Lactobacillus sp; Mannans - chemistry; Mannose - chemistry; Oligosaccharides - biosynthesis; Oligosaccharides - chemistry; Plant Gums - chemistry; Prebiotics - microbiology; β-manno-oligosaccharides; Lactobacillus sp; Enteropathogens; Endo-mannanase; β-manno-oligosaccharides; Guar gum
• ISSN: 0008-6215; 1873-426X
• DOI: 10.1016/j.carres.2019.107822

Size exclusion chromatography of short chain β-manno-oligosaccharides (GG-β-MOS) produced after endo-mannanase (ManB-1601) hydrolysis of guar gum resulted in seven (P1–P7) peaks. Electron spray ionization mass-spectrometry (ESI-MS) revealed P3, P4, P5 and P6 peaks as pentasaccharide (DP5), tetrasaccharide (DP4), trisaccharide (DP3) and disaccharide (DP2), respectively. DP2 and DP3 GG-β-MOS were structurally characterized by NMR (1H and 13C), FTIR and XRD. DP2 GG-β-MOS was composed of two species (A) mannopyranose β-1,4 mannopyranose and (B) α-1,6-galactosyl-mannopyranose while, DP3 oligosaccharide showed presence of three species i.e. (A) α-d-galactosyl-β-d-mannobiose (galactosyl residue at reducing end), (B) α-d-galactosyl-β-d-mannobiose (galactosyl residue at non-reducing end) and (C) mannopyranose β-1,4 mannose β-1,4 mannopyranose. In batch fermentation, DP2 GG-β-MOS was preferred over DP3 by all Lactobacillus sp. except Lactobacillus casei var rhamnosus. DP2/DP3 and GG-β-MOS mixture inhibited the growth of enteropathogens in monoculture and co-culture fermentations, respectively. Fermentation of GG-β-MOS mixture by Lactobacillus sp. produced short chain fatty acids. [Display omitted] •Structural (ESI-MS, NMR, FTIR, XRD) characterization of purified GG-β-MOS.•DP2 and DP3 GG-β-MOS were composed of two and three species, respectively.•DP2 GG-β-MOS is preferred over DP3 by Lactobacillus sp.•DP2 and DP3 GG-β-MOS inhibit the growth of enteropathogens.•GG-β-MOS mixture inhibit the growth of Salmonella typhi in co-culture fermentation.