Surface activities, biodegradability and antimicrobial properties of n‐alkyl glucosides, mannosides and galactosides

Abstract

n-Alkyl a-and fl-glucopyranosides, a-D-mannopyranosides and fi-D-galactopyranosides with alkyl chains having from 8 to 12 carbon atoms were synthesized and their surface properties--such as static surface tension (7), critical micelle concentration (CMC), occu, pation area of molecule, dynamic surface tension and foaming properties, biodegradability and antimicrobial activities -were evaluated. Alkyl glycosides containing C8 to C 12 carbon chains showed surface activities and critical micelle concentrations. D-Glucoside, Dmannoside and D-galactoside having the same alkyl chain showed similar surface tension lowering at CMC (Ycmc) and occupation area of the molecule at the surface. Among the alkyl glucosides, a-anomers were less hydrophilic than fl-anomers. All alkyl glycosides tested in this study were readily biodegraded by activated sludge of a municipal sewage plant compared to those of ethoxylated nonionic alcohols. The difference of the hydrophilic glycopyranoside group in biodegradability was not seen clearly, n-Alkyl glycosides containing C8 to C12 alkyl chains showed a broad spectrum of increasing antimicrobial activity, n-Dodecyl a-D-mannopyranoside was the most effective, the order of antimicrobial activity being mannopyranoside > glucopyranoside > galactopyranoside group. Members of this class of compounds exhibit the physicochemical and biological properties needed both for a wide range of applications and for environmental acceptance.

Improved Transferase/Hydrolase Ratio through Rational Design of a Family 1 β-Glucosidase from Thermotoga neapolitana

“…A group of surfactants with attractive properties are alkyl glycosides, exhibiting antimicrobial activity, biodegradability, and low toxicity (2). These nonionic surfactants find their use mainly in cosmetics, pharmaceuticals, and the food industry.…”

Transgalactosylation in a Water-Solvent Biphasic Reaction System with β-Galactosidase Displayed on the Surfaces of Bacillus subtilis Spores

“…However, because of the low stability of the enzyme in solvents and a strong limitation in mass transfer between water and solvent phases separating enzymes and substrates, it was difficult to obtain a significant yield of glycosylation products (18). We addressed these problems with spore-displayed ␤-Gal and more efficiently produced alkyl-␤-galactosides, a group of nonionic surfactants which exhibit antimicrobial activity and are used as drug intermediates (16). Interestingly, the spores were partitioned mainly at the interface between the water and solvent phases, and they were more available for catalysis between the two phases.…”

Separation of Alkylβ-d-Glucosides andn-Alcohols by Using a Porous Trimethylolpropane Trimethacrylate Homopolymer Gel

“…The glucose residue of alkyl glucosides is more hydrophilic and bulky than the hydroxyl group, so that the 4.0 methylene groups of alkyl glucosides are incorporated into the solvent phase. Symbols x and + are the residual areas per molecule determined from surface tension measurements of the alkyl glucosides, 15,16) which are much 15) The broken curve shows the surface tension of pure n-alcohols. 16) smaller in value than the areas obtained here.…”

“…Symbols x and + are the residual areas per molecule determined from surface tension measurements of the alkyl glucosides, 15,16) which are much 15) The broken curve shows the surface tension of pure n-alcohols. 16) smaller in value than the areas obtained here. This can be explained by the alkyl residue being arranged vertically at the water-air interface, but lying horizontally at the gel-solvent interface.…”