Oligosaccharides enzymatic hydrolysis

Among the best known and most versatile hosts are the various cydodextrins [1,2] of which a-, P- and y-cyclodextrins are the most available. These are cyclic oligosaccharides built up of six, seven, or eight glucopyranose units, respectively. These compounds can be prepared by enzymatic hydrolysis of starch. The undoubtedly most important member of the cyclodextrin family is P-cyclodextrin (P-CD) which has become a cheap and easily available chemical, suitable for large scale applications. Schemes... 

Table IV. Enzymatic Hydrolysis of the High-Molecular Fraction of Steamed Birchwood Xylan. The substrate was fractionated by ultrafiltration prior to hydrolysis to remove impurities and the 1-5 DP oligosaccharides. Substrate concentration 10 gl— 1, initial pH 5, temperature 45°C, hydrolysis time 24 h...

Engfer, M. B., Stahl, B., Finke, B., Sawatzki, G., and Daniel, H. (2000). Human milk oligosaccharides are resistant to enzymatic hydrolysis in the upper gastrointestinal tract. Am. ]. Clin. Nutr. 71,1589-1596. 

The structures of oligosaccharides and polysaccharides are usually determined by a combination of methods specific enzymatic hydrolysis to determine stereochemistry and produce smaller fragments for further analysis methylation analysis to locate glycosidic bonds and stepwise degradation to determine sequence and configuration of anomeric carbons. 

Takahashi, R., Mizumoto, K., Tajika, K., and Takano, R., Production of oligosaccharides from hemicellulose of woody biomass by enzymatic-hydrolysis. 1. A simple method for isolating beta-D-mannanase-producing microorganisms. Mokuzai Gakkaishi 1992, 38 (12), 1126-1135. 

Later on, several studies were devoted to verification and correction of the primary signal assignments in the 13C NMR spectra of galactans and their fragments. Oligosaccharides obtained after enzymatic hydrolysis of galactans were commonly used as model compounds. Different papers contain spectral information concerning... 

Maltitol solution is prepared by the hydrogenation of a high-maltose syrup that is obtained from starch by enzymatic hydrolysis. The maltitol solution produced from this process consists of the hydrogenated homologs of the oligosaccharides contained in the original syrup. 

Enzymatic hydrolysis of polysaccharides (cellulose, starch) or oligosaccharides (maltose, saccharose, lactose) for the synthesis of food products is another class of processes MBR have been applied to. Paolucci-Jeanjean et al [4.56] have recently reported, for example, the production of low molecular weight hydrolysates from the reaction of cassava starch over a-amylase. In this case the UF membrane separates the enzyme and substrate from the reaction products for recycle. Good productivity without noticeable enzyme losses was obtained. Houng et al [4.57] had similar good success with maltose hydrolysis using the same type of MBR,... 

When the experiment was completed, the container was removed from the RF chamber and cooled at room temperature. The treated slurry was filtered through a Whatman no. 4 filter paper in a Buchner funnel. The filtered cakes were washed by deionized water to neutralize the pH to 7.0 and stored for enzymatic hydrolysis. The liquid fraction after pretreatment contained oligosaccharides, which could not be easily quantified thus, an extra step was performed to convert those oligosaccharides into monosaccharides before monosaccharide measurement. National Renewable Enei f Laboratory (NREL) procedure (LAP 002) was used for this conversion [16]. 

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