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Enzymatic surface hydrolysis of poly(ethylene terephthalate) and bis(benzoyloxy...
Eberl, A.; Heumann, Sonja; Brückner, T.; Araújo, Rita; Paulo, Artur Cavaco; Kaufmann, F.; Kroutil, W.; Gübitz, Georg M.A lipase from Thermomyces lanuginosus and cutinases from Thermobifida fusca and Fusarium solani hydrolysed poly(ethylene terephthalate) (PET) fabrics and films and bis(benzoyloxyethyl) terephthalate (3PET) endo-wise as shown by MALDI-Tof-MS, LC–UVD/MS, cationic dyeing and XPS analysis. Due to interfacial activation of the lipase in the presence of Triton X-100, a seven-fold increase of hydrolysis products relea...
A novel aryl acylamidase from Nocardia farcinica hydrolyses polyamide
Heumann, Sonja; Eberl, A.; Fischer-Colbrie, Gudrun; Pobeheim, Herbert; Kaufmann, F.; Ribitsch, D.; Paulo, Artur Cavaco; Gübitz, Georg M.An alkali stable polyamidase was isolated from a new strain of Nocardia farcinica. The enzyme consists of four subunits with a total molecular weight of 190 kDa. The polyamidase cleaved amide and ester bonds of water insoluble model substrates like adipic acid bishexylamide and bis(benzoyloxyethyl)terephthalate and hydrolyzed different soluble amides to the corresponding acid. Treatment of polyamide 6 with this...
Functionalization of cellulose acetate fibers with engineered cutinases
Matamá, Maria Teresa; Araújo, Rita; Gübitz, Georg M.; Casal, Margarida; Paulo, Artur CavacoIn the present work, we describe for the first time the specific role of cutinase on surface modification of cellulose acetate fibers. Cutinase exhibits acetyl esterase activity on diacetate and triacetate of 0.010 U and 0.007 U, respectively. An increase on the hydroxyl groups at the fiber surface of 25% for diacetate and 317% for triacetate, after a 24 h treatment, is estimated by an indirect assay. Aiming at...
Enzymes go big : surface hydrolysis and functionalisation of synthetic polymers
Gübitz, Georg M.; Paulo, Artur CavacoEnzyme technology has progressed from the biotransformation of small substrates to biotransformation of synthetic polymers. Important breakthroughs have been the isolation and design of novel enzymes with enhanced activity on synthetic polymer substrates. These were made possible by efficient screening procedures and genetic engineering approaches based on an in-depth understanding of the mechanisms of enzymes ...
Enzymatic hydrolysis of PTT polymers and oligomers
Eberl, A.; Heumann, Sonja; Kotek, R.; Kaufmann, F.; Mitscher, S.; Paulo, Artur Cavaco; Gübitz, Georg M.Article in Press ; Oligomers and polymers (film, fabrics) of the linear aromatic polyester poly(trimethylene terephthalate) (PTT) were treated with polyesterases from Thermomyces lanuginosus, Penicillium citrinum, Thermobifida fusca and Fusarium solani pisi. The cutinase from T. fusca was found to release the highest amounts of hydrolysis products from PTT materials and was able to open and hydrolyse a cyclic ...
Surface hydrolysis of polyamide with a new polyamidase from Beauveria brongniartii
Almansa, Eva; Heumann, Sonja; Eberl, A.; Kaufmann, F.; Paulo, Artur Cavaco; Gübitz, Georg M.Twelve fungi were screened for the potential of their extracellular enzymes to increase the hydrophilicity of polyamide (PA) materials. The most pronounced increase in hydrophilicity was found for enzymes from Beauveria brongniartii and B. bassiana. The 55 kDa polyamidase from B. brongniartii was purified using ultrafiltration, anion exchange chromatography and size exclusion chromatography. This polyamidase wa...
Effect of the agitation on the adsorption and hydrolytic efficiency of cutinase...
O'Neill, Jaime Alexandre Antunes; Araújo, Rita; Casal, Margarida; Gübitz, Georg M.; Paulo, Artur CavacoThe effect of agitation on adsorption, desorption and hydrolytic efficiency of a native and a genetically modified cutinase (L182A) on polyethylene terephthalate fibres is reported in this paper. The effect of mechanical agitation was studied using a shaker bath with orbital agitation and a Rotawash machine with vertical agitation with and without extra steel discs inside the reaction pots. The results obtained...
Laccase immobilization on enzymatically functionalized polyamide 6,6 fibres
Silva, Carla Manuela; Silva, Carla Joana; Zille, Andrea; Gübitz, Georg M.; Paulo, Artur CavacoPolyamide matrices, such as membranes, gels and non-wovens, have been applied as supports for enzyme immobilization, although in literature the enzyme immobilization on woven nylon matrices is rarely reported. In this work, a protocol for a Trametes hirsuta laccase immobilization using woven polyamide 6,6 (nylon) was developed. A 24 full factorial design was used to study the influence of pH, spacer (1,6-hexane...
Enzymatic reduction of azo and indigoid compounds
Pricelius, S.; Held, C.; Murkovic, M.; Bozic, M.; Kokol, V.; Paulo, Artur Cavaco; Gübitz, Georg M.A customer- and environment-friendly method for the decolorization azo dyes was developed. Azoreductases could be used both to bleach hair dyed with azo dyes and to reduce dyes in vat dyeing of textiles. A new reduced nicotinamide adenine dinucleotide-dependent azoreductase of Bacillus cereus, which showed high potential for reduction of these dyes, was purified using a combination of ammonium sulfate precipita...
Decolourisation of a synthetic textile effluent using a bacterial consortium
Ramalho, Patrícia A.; Cardoso, M. Helena; Ramalho, Maria Teresa; Gübitz, Georg M.; Paulo, Artur CavacoIn the present study we examined the performance of a thermoalkalophilic bacterial consortium, where the predominant strain was Bacillus sp. SF, in the degradation of Reactive Black 5 (RB5). We used a reactor working in continuous mode and investigated the effects of pH, hydraulic retention time (HRT) and several added salts on colour and chemical oxygen demand (COD) reductions. For the chosen operational condi...
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