Optimization of Isomaltooligosaccharide Size Distribution by Acceptor Reaction of Weissella confusa Dextransucrase and Characterization of Novel α-(1→2)-Branched Isomaltooligosaccharides

Abstract

Long-chain isomaltooligosaccharides (IMOs) are promising prebiotics. IMOs were produced by a Weissella confusa dextransucrase via maltose acceptor reaction. The inputs of substrates (i.e., sucrose and maltose, 0.15-1 M) and dextransucrase (1-10 U/g sucrose) were used to control IMO yield and profile. According to response surface modeling, 1 M sucrose and 0.5 M maltose were optimal for the synthesis of longer IMOs, whereas the dextransucrase dosage showed no significant effect. In addition to the principal linear IMOs, a homologous series of minor IMOs were also produced from maltose. As identified by MS(n) and NMR spectroscopy, the minor trisaccharide contained an α-(1→2)-linked glucosyl residue on the reducing residue of maltose and thus was α-d-glucopyranosyl-(1→2)-[α-d-glucopyranosyl-(1→4)]-d-glucopyranose (centose). The higher members of the series were probably formed by the attachment of a single unit branch to linear IMOs. This is the first report of such α-(1→2)-branched IMOs produced from maltose by a dextransucrase.

Site Directed Mutagenesis of Dextransucrase DsrM from Weissella cibaria: Transformation to a Reuteransucrase

“…Isomalto-oligosaccharides structure and DP are depending on glucansucrase specificity and substrate concentration. Different ratio of sucrose and maltose concentration altered the acceptor reaction of isomalto-oligosaccharides production toward higher or lower DP values . DsrM-S693N:E694N:V695S did not produce high DP panose-series oligosaccharides in the acceptor reaction with maltose formation, matching previous observations with the analogous mutant GtfA-S1135N:A1137S .…”

“…Lactic acid bacteria in the genera of Lactobacillus , Weissella , Leuconostoc , and Streptococcus produce glucans and gluco-oligosaccharides from sucrose by extracellular glucansucrases . Gluco-oligosaccharides, such as isomalto-oligosaccharides, are commercially applied as prebiotics. , Polymeric glucans, such as dextran, are used as food hydrocolloids. , Beneficial technological or functional effects of glucans relate to their linkage type and molecular weight. , …”

“…4,5 Beneficial technological or functional effects of glucans relate to their linkage type and molecular weight. 3,6 Glucans are categorized based on their linkage type: predominantly α-(1→6) linked dextran is synthesized by dextransucrases from Leuconostoc, Streptococcus, and Weissella; α-(1→3) and α-(1→6) linked alternan are synthesized by some strains of Leuconostoc and Streptococcus; predominantly α-(1→ 3) linked mutan is synthesized by Streptococcus; and predominantly α-(1→4) linked reuteran is synthesized by reuteransucrases from L. reuteri. 1 Glucansucrases are GH70 family enzymes in the α-amylase superfamily and contain an amylase-type catalytic (α/β) 8 -barrel.…”

A Survey of Commercially Available Isomaltooligosaccharide‐Based Food Ingredients

“…Type 3 are linear chains of either the type 1 or type 2, but are also branched to glucose via α‐1,2, α‐1,3, or α‐1,4 linkages. These side chains may extend beyond a single residue, usually via α‐1,6 linkages, or the novel centose‐type (Shi and others ), originally proposed by Goffin and others ().…”

Heterologous Expression of a Thermostable α-Glucosidase from Geobacillus sp. Strain HTA-462 by Escherichia coli and Its Potential Application for Isomaltose–Oligosaccharide Synthesis

“…Isomalto–oligosaccharides (IMOs) are a group of functional oligosaccharides with a degree of polymerization (DP) ranging 2–10, which consist of glucosyl saccharide units linked by α-1, 6-glycosidic linkages [1]. Isomaltose, panose, isomaltotriose and tetrasaccharides are defined as the main functional components of IMOs [2]. As functional oligosaccharides, which are non-digestible in nature, IMOs have the function of regulating intestinal flora by promoting the proliferation of Bifidobacterium and Lactobacillus in the human intestinal tract [3], and also have the additional properties of: low caloric value [4], the promotion of gastrointestinal peristalsis, and the improvement of constipation and lipid metabolism [5,6].…”