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Enzymatic polymerization of phenolic compounds (catechol, resorcinol, and hydroquinone) was carried out using laccase. The mechanism of polymerization and the structures of the polymers were evaluated in terms of UV-Vis and Fourier transform infrared spectroscopy. The molecular weights of the produced polyphenols were determined with GPC. The results showed that the phenolic monomers firstly turned into quinone intermediates by laccase catalysis. Through further oxidation, the intermediates formed covalent bonds. Finally, catechol units were linked together with ether bonds, and both resorcinol and hydroquinone units were linked together with C-C bonds. The number-average molecular weights of the polyphenols ranged from 1,000 to 1,400 Da (corresponding to the degree of polymerization that varied from 10 to 12) with a lower polydispersity value of about 1.10, showing selective polymerization of phenolic compounds catalyzed by laccase.

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Greater attention has been given to enzymatic processes of textiles as effective alternatives to conventional chemical treatments because of the non-toxic and eco-friendly characteristics of enzymes as well as the increasingly important requirement for reducing pollution in textile production. A new functionalization method for wool fabrics based on immobilization of lysozymes was investigated in this paper. Wool fabric was first activated with glutaraldehyde, and then employed to covalently immobilize lysozymes. Main immobilization parameters were optimized in terms of the activity of immobilized enzyme. A high activity of the immobilized enzyme was obtained when the fabric was activated at 25 degrees C for 6 h in a bath containing with 0.2% of glutaraldehyde followed by the immobilization at 4 degrees C and pH 7.0 for 6 h with 5 g l(-1) lysozyme. The scanning electron microscopy and staining tests based on modified Coomassie protein assay (Bradford method) revealed that the lysozyme was fixed covalently on the wool fabric. Wool fabrics immobilizing lysozymes presented a higher ratio of bacteriostasis to Staphylococcus aureus. The durability of antibacterial wool was assessed and the lysozyme immobilized on wool fabric retained ca. 43% of its activity after five cycles of use when taking the activity of the immobilized lysozyme before using as reference.