76867-26-0Relevant academic research and scientific papers
Enzymatic fructosylation of aromatic and aliphatic alcohols by Bacillus subtilis levansucrase: Reactivity of acceptors
Mena-Arizmendi, Arlette,Alderete, Joel,Aguila, Sergio,Marty, Alain,Miranda-Molina, Alfonso,Lopez-Munguia, Agustin,Castillo, Edmundo
experimental part, p. 41 - 48 (2012/02/03)
Levansucrases from Bacillus subtilis (BS-LVS) and Leuconostoc mesenteroides ssp. mesenteroides ATCC 8293 (LevC), inulosucrase from Leuconostoc citreum (IslA) and an invertase from Saccharomyces cerevisiae (Inv) were evaluated in acceptor reactions with non-sugar acceptors. Among them, BS-LVS was selected for the fructosylation of aromatic or aliphatic alcohols due to its high activity and stability. The effects of acceptor concentration, enzyme concentration and the presence of a co-solvent in the fructosylation efficiency of hydroquinone were evaluated. It was demonstrated that this reaction is kinetically controlled, producing the best yields of phenolic fructosides when 500 mM of acceptor and 5 U mL-1 of enzyme were employed. Higher enzyme loads resulted in the rapid hydrolysis of the products. Increased amounts of organic co-solvent up to 50% (v/v) reduced fructoside yield due to a concomitant decrease in the thermodynamic activity of the acceptor, as confirmed by theoretical calculations using COSMO-RS; moreover, increased fructose transfer to levan and reduced hydrolysis were observed. It was found that BS-LVS preferentially fructosylates aromatic over aliphatic alcohols. A maximum fructoside production (19-35 mM) was obtained with dihydroxybenzene acceptors such as hydroquinone, whereas reactions with primary alcohols, such as benzyl alcohol resulted in lower fructosylation efficiency. This selectivity was also demonstrated by the fact that 4-hydroxybenzylalcohol, a bifunctional acceptor, was fructosylated at a rate ten times faster on its aromatic hydroxyl group. BS-LVS selectivity over phenol fructosylation was inversely correlated with the acceptor pKa value.
FORMATION AND EQUILIBRATION OF D-FRUCTOSIDES AND 2-THIO-D-FRUCTOSIDES IN ACIDIFIED DIMETHYL SULFOXYDE: SYNTHETIC AND MECHANISTIC ASPECTS
Moody, Wayne,Richards, Geoffrey N.
, p. 201 - 214 (2007/10/02)
A kinetic study of the reaction of ketoses and ketosides under catalysis with very dilute acid to produce the ketosyl carbonium ion is reported, and the subsequent reaction of this ion with alcohol and thiol nucleophiles has been studied.The relative reactivity of D-fructoses and 2-thio-fructosides is discussed, and some tentative conclusions have been reached on the mechanism of their furanoside-pyranoside equilibration.The change in ring size in such systems probably proceeds via an anhydro-D-fructose intermediate, rather than an acyclic intermediate.The synthetic applications of the system have been explored, and it has been shown that both D-fructosides and 2-thio-D-fructosides may be synthesized in good yield.The D-fructofuranosides are best obtained from sucrose as the starting material, whereas the pyranosides are obtained from any readily available D-fructopyranoside (e.g., methyl β) by use of the desired alcohol or thiol, only the β anomers being obtained.Three new 2-thio-D-fructosides are reported.
THERMOLYSIS OF SUCROSE IN THE PRESENCE OF ALCOHOLS. A NOVEL METHOD FOR THE SYNTHESIS OF D-FRUCTOFURANOSIDES
Moody, Wayne,Richards, Geoffrey N.
, p. 247 - 256 (2007/10/02)
When sucrose is thermolyzed in the presence of alcohols, either neat or in dimethyl sulfoxide solution, the products are mainly D-glucose and the appropriate alkyl D-fructofuranosides.Conditions have been investigated for optimizing the yields of the latter products, with a view to utilization of the reaction as a synthetic method.Such sterically hindered alcohols as 2-methyl-2-propanol and three sterols did not readily take part in the reaction.Phenols appear to undergo the reaction, but the phenyl D-fructofuranosides are probably degraded subsequently, to give increased yields of 2,6-anhydro-D-fructofuranose.
THERMOLYSIS OF SUCROSE IN DIMETHYL SULPHOXIDE SOLUTION
Poncini, Laurence,Richards, Geoffrey N.
, p. 209 - 218 (2007/10/02)
The kinetics of thermolysis of sucrose in solution in anhydrous dimethyl sulphoxide have been studied.The reaction appears to be facilitated by intramolecular hydrogen-bonding and is inhibited by intermolecular hydrogen-bonding to water or alcohols.The thermolysis yields α-D-glucopyranose (which then anomerises) and the fructofuranosyl carbonium ion which can react with benzyl alcohol to yield benzyl α- and β-D-fructofuranosides.This fructosyl cation is probably also the precursor for the formation of 2,6-anhydrofructofuranose in the thermolysis of sucrose.
