Glucosides enzymatic

Synthesis of naturally occurring (J-D-glucopyranosides based on enzymatic P-glucosidation using -glucosidase from almond... 

The authors conducted preliminary biological investigation on these complexes, studying their stability toward enzymatic hydrolysis. Interestingly, the glucoside residue was not released from the complexes under the action almond /j-glucosidase,... 

The effectiveness of proteolytic, amylolytic, and lipolytic detergent enzymes is based on enzymatic hydrolysis of peptide, glucosidic, or ester linkages. The mainstay of the market has been the protease types. 

Cascade catalysis without recovery of intermediate products may require more than two steps, involving enzymatic, homogeneous, and heterogeneous catalysis. Several examples of this approach have been given [72, 73] one of the most representative consists of a four-step conversion of glucoside into aminodeoxysugar without intermediate product recovery. 

Table 7.3 Repeated alkyl fS-D-glucoside use 7.3 Facile Synthesis of Alkyl P-o-Glucopyranosides 237 ofP. dulcis kernel meal in the enzymatic synthesis of ... 

S. Veibel, Enzymatic and acid hydrolysis of glucosides, Kent. Maanedsblad, 20 (1939) 253-258. 

It therefore appeared that a general mechanism for enzymatic esterification of phenolic acids with glucose was operative, whereas the reaction with other alcoholic moieties proceeded via carboxyl-activated acyl derivatives. [In this context it should be emphasized that glucose esters must not be confused with glucosides different enzymes are involved in the biosynthesis of these two types of phenolic glucose derivatives (36)]. 

Figure 1. Postulated pathway for the enzymatic synthesis of polymethylated flavonol glucosides in Chrysosplenium americanum GT, O-glucosyl-transferase OH, hydroxylase OMT, O-methyl transferase.

In 2002, Do et al. [85] proposed a pathway for the enzymatic synthesis of (-)-menthyl a-maltoside and a-maltooligosides from (-)-menthyl a-glucoside using cyclodextrin glucanotransferase obtained from Bacillus macerans. The reaction can be performed in a reactor containing (-)-menthyl a-glucoside, the enzyme and soluble starch the yield was about 80% 15% (-)-menthyl a-malto-side and 65% (-)-menthyl a-maltooligosides, respectively. Treatment of the starch with a-amylase can raise the proportion of (-)-menthyl a-maltoside. 

Other attempts make use of the better CNS penetration of kynurenine which is converted enzymatically within the brain to kynurenic acid by kynurenine aminotransferase (Hokari et al., 1996) or the design of pro-drugs which enter the CNS more easily and are hydrolyzed within the brain e g. glucosidic-linked 7-chlorokynurenic acid (Bonina et al., 2000). 

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