499-39-8

Upstream product

• 83921-77-1 benzyl O-(2,3,4,6-tetra-O-benzyl-β-D-glucopyranosyl)-(1<*>6)-O-(2,3,4-tri-O-benzyl-α-D-glucopyranosyl)-(1<*>6)-2,3,4-tri-O-benzyl-α-D-glucopyranoside 
• 536-11-8 D-melibiose 
• 57-50-1 Sucrose 
• 7493-95-0 4-nitrophenyl α-D-galactoside 
• 470-55-3 stachyose 

Relevant academic research and scientific papers

Study of influential factors on oligosaccharide formation by fructosyltransferase activity during stachyose hydrolysis by pectinex ultra SP-L

The influence of reaction conditions for oligosaccharide synthesis from stachyose using a commercial enzymatic preparation from Aspergillus aculeatus (Pectinex Ultra SP-L) was studied. Oligosaccharides were analyzed by gas chromatography with flame ionization detection (GC-FID) and matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS). Galactosyl-melibiose (DP3) was synthesized as a result of fructosidase activity, whereas fructosyl-stachyose (DP5) and difructosyl-stachyose (DP6) were formed as a consequence of the fructosyltransferase activity of Pectinex Ultra SP-L. The optimal reaction conditions for the synthesis of penta-and hexasaccharides were 60 °C, pH 5.5, 600 mg/mL stachyose, and 34 U/mL enzyme. Reaction time played an important role in oligosaccharide mixture composition constituted by 20% DP5, 0.7% DP6, 55% stachyose, 21% galactosyl-melibiose, and 1% monosaccharides after 1 h and 16% DP5, 4% DP6, 27% stachyose, 44% galactosyl-melibiose, and 2% monosaccharides after 3 h. In conclusion, stachyose could be used as a substrate for the enzymatic synthesis of new oligosaccharides that may open new opportunities in the development of future prebiotics.

Mode of action of a β-(1→6)-glucanase from Penicillium multicolor

β-(1→6)-Glucanase from the culture filtrate of Penicillium multicolor LAM7153 was purified by ammonium sulfate precipitation, followed by cation-exchange and affinity chromatography using gentiotetraose (Gen 4) as ligand. The hydrolytic mode of action of the purified protein on β-(1→6)-glucan (pustulan) was elucidated in real time during the reaction by HPAEC-PAD analysis. Gentiooligosaccharides (DP 2-9, Gen 2-9), methyl β-gentiooligosides (DP 2-6, Gen2-6 β-OMe), and p-nitrophenyl β-gentiooligosides (DP 2-6, Gen 2-6 β-pNP) were used as substrates to provide analytical insight into how the cleavage of pustulan (DP? 320) is actually achieved by the enzyme. The enzyme was shown to completely hydrolyze pustulan in three steps as follows. In the initial stage, the enzyme quickly cleaved the glucan with a pattern resembling an endo-hydrolase to produce a short-chain glucan (DP? 45) as an intermediate. In the midterm stage, the resulting short-chain glucan was further cleaved into two fractions corresponding to DP 15-7 and DP 2-4 with great regularity. In the final stage, the lower oligomers corresponding to DP 3 and DP 4 were very slowly hydrolyzed into glucose and gentiobiose (Gen 2). As a result, the hydrolytic cooperation of both an endo-type and saccharifying-type reaction by a single enzyme, which plays a bifunctional role, led to complete hydrolysis of the glucan. Thus, β-(1→6)-glucanase varies its mode of action depending on the chain length derived from the glucan.

Aspergillus nidulans α-galactosidase of glycoside hydrolase family 36 catalyses the formation of α-galacto-oligosaccharides by transglycosylation

The α-galactosidase from Aspergillus nidulans (AglC) belongs to a phylogenetic cluster containing eukaryotic α-galactosidases and -galacto-oligosaccharide synthases of glycoside hydrolase family 36 (GH36). The recombinant AglC, produced in high yield (0.65 g·L-1 culture) as His-tag fusion in Escherichia coli, catalysed efficient transglycosylation with α-(1→6) regioselectivity from 40 mm 4-nitrophenol -d-galactopyranoside, melibiose or raffinose, resulting in a 37-74% yield of 4-nitrophenol α-d-Galp-(1→6) α-d-Galp, α-d-Galp- (1→6) α- d-Galp-(1→6) α-d-Glcp and α-d-Galp- (1→6) α- d-Galp-(1→6) α-d-Glcp-(1→2) α-d-Fruf (stachyose), respectively. Furthermore, among 10 monosaccharide acceptor candidates (400 mm) and the donor 4-nitrophenol -d-galactopyranoside (40 mm), -(1→6) linked galactodisaccharides were also obtained with galactose, glucose and mannose in high yields of 39-58%. AglC did not transglycosylate monosaccharides without the 6-hydroxymethyl group, i.e. xylose, l-arabinose, l-fucose and l-rhamnose, or with axial 3-OH, i.e. gulose, allose, altrose and l-rhamnose. Structural modelling using Thermotoga maritima GH36 -galactosidase as the template and superimposition of melibiose from the complex with human GH27 α-galactosidase supported that recognition at subsite +1 in AglC presumably requires a hydrogen bond between 3-OH and Trp358 and a hydrophobic environment around the C-6 hydroxymethyl group. In addition, successful transglycosylation of eight of 10 disaccharides (400 mm), except xylobiose and arabinobiose, indicated broad specificity for interaction with the +2 subsite. AglC thus transferred -galactosyl to 6-OH of the terminal residue in the -linked melibiose, maltose, trehalose, sucrose and turanose in 6-46% yield and the -linked lactose, lactulose and cellobiose in 28-38% yield. The product structures were identified using NMR and ESI-MS and five of the 13 identified products were novel, i.e. α-d-Galp-(1→6) α-d-Manp; α-d-Galp-(1→6) α- d-Glcp-(1→4) α-d-Glcp; α-d-Galp-(1→6) α- d-Galp-(1→4) α-d-Fruf; α-d-Galp-(1→6) α-d-Glcp-(1→1) α-d-Glcp; and α-d-Galp-(1→6) α- d-Glcp-(1→3) α-d-Fruf.

Rapid oligosaccharide synthesis on a fluorous support

The novel fluorous support Hfb (hexakisfluorous chain-type butanoyl) was easily prepared. The Hfb group was readily introduced into the anomeric hydroxyl group of a carbohydrate, and was recyclable after cleavage. The use of the Hfb group was applicable for the rapid oligosaccharide synthesis in which the synthetic intermediates could be purified using fluorous and normal organic solvents. Each synthetic intermediate could be monitored by TLC, NMR and mass spectrometry. Graphical Abstract

Dehydrative Glycosylation Using Heptabenzyl Derivatives of Glucobioses and Lactose

Dehydrative glycosylations of the 2-, 3-, 4-, and 6-OH groups of D-glucopyranose with hepta-O-benzyl derivatives of glucobioses (O-D-glucopyranosyl-(1->n)-D-glucopyranose; n = 2, 3, 4, or 6) and lactose, in the presence of a ternary mixture of p-nitrobenzenesulfonyl chloride, silver trifluoromethanesulfonate, and triethylamine in dichloromethane showed that the selectivity of the reaction depended on the anomeric configuration and the linking position to the reducing tribenzylglucose moiety of the nonreducing tetrabenzylglucosyl residue and on the class of the OH group to be glycosylated.The use of a quaternary mixture of p-nitrobenzenesulfonyl chloride, silver trifluoromethanesulfonate, N,N-dimethylacetamide, and triethylamine made all but the β(1->2)-linked biosyl donor undergo α-condensation.Several new linear trisaccharides were obtained via debenzylation of the condensates.