Functionalised multi-walled carbon nanotubes (MWCNTs) were cast on glassy carbon (GC) and carbon film electrodes (CFE), and were haracterised electrochemically and applied in a glucose-oxidase-based biosensor. MWCNT-modified carbon film electrodes were then used to evelop an alcohol oxidase (AlcOx) biosensor, in which AlcOx–BSA was cross-linked with glutaraldehyde and attached by drop-coating. ...

The oxidation of alcohols to the corresponding carbonyl or carboxyl compounds represents a convenient strategy for the selective introduction of electrophilic carbon centres into carbohydrate-based starting materials. The O₂-dependent oxidation of prim-alcohols by flavin-containing alcohol oxidases often yields mixtures of aldehyde and carboxylic acid, which is due to "over-oxidation" of the al...

Ascorbate is a crucial antioxidant for scavenging hydrogen peroxide generated from the physiological processes and environmental stresses. Besides, the endo/exogenous factors that influence ascorbate level, our knowledge of the methanol stimulation is relatively less. Methanol, a byproduct from the demethylation of pectin during the enlargement of plant cell, is effective in enhancing the expre...

A novel poly(vinyl alcohol) grafting 4-vinylpyridine self-gelatinizable copolymer was adapted to immobilize glucose oxidase. The reduction of hydrogen peroxide (H2O2) was detected at a Prussian Blue (PB) modified graphite electrode. A stable and sensitive glucose amperometric biosensor is described. The copolymer is a good biocompatible polymer in which the glucose oxidase retains high activity...

Fungal lignin-degrading systems likely include membrane-associated proteins that participate in diverse processes such as uptake and oxidation of lignin fragments, production of ligninolytic secondary metabolites, and defense of the mycelium against ligninolytic oxidants. Little is known about the nature or regulation of these membrane-associated components. We grew the white rot basidiomycete ...

Three model, unrelated enzymes (yeast alcohol oxidase, mushroom polyphenol oxidase, and horse liver alcohol dehydrogenase) were found to be catalytically active in a variety of organic solvents. For all enzymes and solvents tested, the enzymatic activity greatly increased upon an increase in the water content in the solvents (which always remained below the solubility limit). Much less water wa...

A new metabolic pathway of L-tryptophan, tentatively referred to as the side chain pathway, was demonstrated in Pseudomonas fluorescens (ATCC 29574), in which the initial reaction was catalyzed by tryptophan side chain oxidase (Takai, K., Ushiro, H., Noda, Y., Narumiya, S., Tokuyama, T., and Hayaishi, 0. (1977) J. Biol. Chem. 252,2648-2656). When the bacteria harvested in the late stationary ph...

The inhibition of the membrane-bound enzyme cytochrome c oxidase by aliphatic n-alcohols and other neutral organic compounds was studied as a model for anaesthetic action and drug toxicity. The n-alcohols (C1 to C14) displayed a variation in inhibition constant of over 500,000-fold. The inhibition constants correlated well with the number of carbon atoms in the n-alcohols and also their n-octan...

The methylotrophic yeast Candida boidinii S2 was found to be able to grow on pectin or polygalacturonate as a carbon source. When cells were grown on 1% (wt/vol) pectin, C. boidinii exhibited induced levels of the pectin-depolymerizing enzymes pectin methylesterase (208 mU/mg of protein), pectin lyase (673 mU/mg), pectate lyase (673 mU/mg), and polygalacturonase (3.45 U/mg) and two methanol-met...

Larvae of the leaf beetle subtribe Chrysomelina sensu stricto repel their enemies by displaying glandular secretions that contain defensive compounds. These repellents can be produced either de novo (iridoids) or by using plant-derived precursors (e.g. salicylaldehyde). The autonomous production of iridoids, as in Phaedon cochleariae, is the ancestral chrysomeline chemical defence and predates ...