Publication Details (including relevant citation information):
Mária Matulová , Slavomíra Husárová , Peter Capek , Martine Sancelme and Anne–Marie Delort
Carbohydr. Res. DOI 10.1016/j.carres.2010.12.012
Bacillus sp. 3B6, bacterium isolated from cloud water, was incubated on sucrose for exopolysaccharide production. Dialysis of obtained mixture (MWCO 500) afforded dialyzate (DIM) and retentate (RIM). Both were separated by size exclusion chromatography. RIM afforded eight fractions: levan exopolysaccharide (EPS), fructooligosaccharides (FOSs) of levan and inulin types with different degree of polymerization (dp 2-6) and monosaccharides fructose: glucose = 9:1. Levan was composed of two components with molecular mass ~ 3500 and ~ 100kDa in the ratio 2.3:1. Disaccharide fraction contained difructose anhydride DFA IV. 1–Kestose, 6–kestose and neokestose were identified as trisaccharides in the ratio 2:1:3. Fractions with dp 4-7 were mixtures of FOSs of levan (2,6–βFruf) and inulin (1,2–βFruf) type. DIM separation afforded two dominant fractions: monosaccharides with fructose: glucose ratio 1:3; disaccharide fraction contained sucrose only. DIM trisaccharide fraction contained 1–kestose, 6–kestose and neokestose in the ratio1.5:1:2, penta and hexasaccharide fractions contained FOSs of levan type (2,6-βFruf) containing α-glucose. In the pentasaccharide fraction also the presence of a homopentasaccharide composed of 2,6-linked βFruf units only was identified. Nystose, inulin (1,2–βFruf) type, was identified as DIM tetrasaccharide. Identification of levan 2,6–βFruf and inulin 1,2–βFruf type oligosaccharides in the incubation medium suggests both levansucrase and inulosucrase enzymes activity in Bacillus sp. 3B6.