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A biological approach for degumming bamboo substrates has been assessed. The ability of various commercially available enzymes, including cellulase, xylanase, pectinase and mannanase, to hydrolyze bamboo powders was investigated. In addition, a commercial cellulase preparation was applied onto bamboo fibre bundles obtained by natural retting. It was found that almost all enzymes applied can use bamboo material as a substrate. Mild autoclave pre-treatment can enhance reducing sugar yield from different enzyme treatments. A most pronounced effect was observed with cellulase treatment in which the hydrolysis degree increased 1.7 fold as measured by reducing sugars for autoclave pre-treated bamboo powders versus non-treated powders after only a short period of incubation. The combined treatment of hemicellulase preparations showed no effect on the hydrolysis of bamboo substrates. The effect of autoclave pre-treatment on cellulase-treated samples was confirmed by the increase of sugar yield, protein absorption as well as by the enhancement of surface modification and enzyme penetration observed by CLSM (confocal laser scanning microscopy). This work establishes a base for future studies to develop enzymatic hydrolysis of bamboo materials, making them suitable for textile processing. [ABSTRACT FROM AUTHOR]

Those oxidoreductases that are part of the ligninolytic complex of basidiomycete and ascomycete fungi have played an increasingly important role in biotechnological applications during the last decade. The stability of these extracellular enzymes, their good solubility, and a multitude of catalyzed reactions contribute to this trend. This review focuses on a single genus of white-rot basidiomycetes, Trametes, to highlight the numerous possibilities for the application of this microorganism as well as three of its enzymes: laccase, cellobiose dehydrogenase, and pyranose 2-oxidase. Whereas laccase is without doubt a major player in biotechnology, the two other enzymes are less well known, but represent emerging biocatalysts with potential. Both cellobiose dehydrogenase and pyranose 2-oxidase are presumed to participate in lignin breakdown and will be used to exemplify the potential of less prominent oxidoreductases from this genus. [ABSTRACT FROM AUTHOR]

Laccase enzymes are multicopper oxidases capable of oxidizing different compounds. However, to be able to use this biocatalyst for industrial applications, their immobilization is needed. The present work investigates the immobilization of Myceliophthora thermophila laccase (MtL) on monodisperse microspheres of poly(glycidyl methacrylate) (PGMA) to be used in azinphos‐methyl degradation. The immobilization was optimized to achieve the highest activity of the immobilized enzyme. As result, the protein load obtained was 2.5 mg protein g−1 carrier (35 U g−1 of carrier). The immobilized enzymes showed a broadened pH and temperature range of optimum activity and significantly improved the storage and operational stability. Finally, the complete degradation of azinphos‐methyl using immobilized laccase was achieved after 1 h of reaction. The collected data indicate that the immobilization of MtL on PGMA microspheres is an excellent alternative to improve biochemical properties in the enzyme and to allow their efficient use in pesticides degradation. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47417. [ABSTRACT FROM AUTHOR]

Enzymatic transformation of recalcitrant and other pollutants is a promising eco-friendly alternative to physico-chemical methods in environmental remediation. This review summarizes some of the significant advances in applications of oxidative enzymes for treatment of xenobiotics. The review also discusses some of the underlying principles and enzyme reaction mechanisms in the detoxification or removal of xenobiotic compounds such as dyes, phenolic compounds, nitroaromatic compounds and polyaromatic hydrocarbons, as a way of remediating contaminated soils or wastewaters.