Mutagenesis and Adaptation of the Psychrotrophic Fungus A-1 as a Method for Improving β-pinene Bioconversion.

Mutagenesis and adaptation of the psychrotrophic fungus A-1 to the toxic substrate β-pinene were used to obtain a biocatalyst with increased resistance to this terpene and improved bioconversion properties. Mutants of the parental strain were induced with UV light and -methyl-'-nitro--nitrosoguanidine. Mutants resistant to β-pinene were isolated using agar plates with a linear gradient of substrate concentrations.

Strain improvement of industrially important microorganisms based on resistance to toxic metabolites and abiotic stress.

Improvement of the biosynthetic capabilities of industrially relevant microbes to produce desired metabolites in higher quantities is one of the important topics of modern biotechnology. In this article, different strategies of improvement of mutated microbial strains are briefly described. This is followed by the first comprehensive review of the literature on obtaining high yielding microorganisms, that is, mutants exhibiting resistance to antimetabolites, nutritional repression, and abiotic stresses as well as tolerance to solvents and toxic substrates or products.

Biological activity of terpene compounds produced by biotechnological methods.

Context: Biotransformation systems are profitable tools for structural modification of bioactive natural compounds into valuable biologically active terpenoids.

Objective: This study determines the biological effect of (R)-(+)-limonene and (-)-α-pinene, and their oxygenated derivatives, (a) perillyl alcohol and (S)-(+)- and (R)-(-)-carvone enantiomers and (b) linalool, trans-verbenol and verbenone, respectively, on human colon tumour cells and normal colonic epithelium.

Materials And Methods: Biotransformation procedures and in vitro cell culture tests were used in this work.

An efficient method for the immobilization of inulinase using new types of polymers containing epoxy groups.

New glycidyl methacrylate copolymers containing different numbers of epoxy groups were synthesized and used to develop effective procedures for inulinase immobilization. The beneficial characteristics of the carriers included a high degree of crosslinking, stability at ambient temperature, an appropriate surface, and the presence of reactive epoxy groups. Some factors affecting the efficiency of immobilization of crude inulinase, including the kind and amount of carrier, the number of epoxy groups, as well as buffer pH and buffer concentration were examined.

Bioconversion of α-pinene by a novel cold-adapted fungus Chrysosporium pannorum.

The psychrotrophic fungus Chrysosporium pannorum A-1 is reported for the first time as a novel biocatalyst for O2-promoted oxidation of α-pinene. GC-MS analysis indicated that the main products of the reaction were compounds of a high commercial value, verbenol (1) and verbenone (2). Exponentially growing cells (days 2-3) were about twice as active as cells in the late stationary phase in terms of the total concentration of products.