Synthesis of fucosylated oligosaccharides using crude enzyme extracts from Bifidobacterium longum subsp. longum RD 47

Abstract

Human milk oligosaccharides (HMOs) are mostly fucosylated at their non-reducing termini. It has been proposed that HMOs function as a prebiotic for bifidobacteria. Through the screening procedure, crude enzyme extracts from Bifidobacterium longum subsp. longum RD 47 were newly found to produce fucosylated oligosaccharides. The synthesized oligosaccharides were further purified from reaction mixture and identified to be as fucosylated galacto-oligosaccharides and galacto-oligosaccharides by thin layer chromatography. The analysis of fucosylated oligosaccharides by mass spectrometry showed that degree of polymerization ranged from 2 to 7. To improve the yield of the production of fucosylated oligosaccharides, the effect of the medium composition on the production of crude enzyme extracts from B.longum RD47 was evaluated and the oligosaccharides synthesis reaction conditions were optimized. The addition of raffinose in culture medium resulted in increased galactosidase activities in crude enzyme extracts from B. longum RD 47.The synthesized fucosylated oligosaccharides may provide a new constituent for the HMOs and novel prebiotic food ingredients.