Environmentally friendly bleaching of cotton using laccases

Abstract

A new strain of Trametes hirsuta was found to oxidize various cotton flavonoids. Here we show that laccases of this organism were responsible for oxidation of the flavonoids morin, luteolin, rutin and quercetin. Out of two laccases produced by T. hirsuta (60.7 and 51.0 kDa) the more prominent 60.7 kDa laccase was purified and showed K m and k cat values of 75.5, 20.9 and 49.4 µM and 72.5, 96.3 and 32.7 s −1 , hours on ABTS, syringaldazide and DMP, respectively. Pretreatment of cotton with the T. hirsuta laccase resulted in a whiteness increase of 8.5%.

Simultaneous production of laccase and decolouration of the diazo dye Reactive Black 5 in a fixed-bed bioreactor

“…The main band likely corresponds to laccase, since no other ligninolytic enzymes were detected in the culture extract, with a molecular weight of about 63 kDa as visualised by Coomassie Brilliant Blue staining. This molecular weight is similar to those found for other laccases from fungal species belonging to the genus Trametes [22][23][24][25][26].…”

A review of preparation of binderless fiberboards and its self-bonding mechanism

“…Laccase, which is widely distributed in plants and fungi, has been intensively studied in the pulp and paper industry. It can catalyze the oxidation of various phenolic substrates (Nyanhongo et al 2010;Kudanga et al 2008;Pereira et al 2005). During the fiber treatments, laccase hardly penetrated into fibers and mainly oxidized the lignin on the surface (Á lvarez et al 2011).…”

Thermophilic laccase from xerophyte species Opuntia vulgaris

“…Laccase is an enzyme known to catalyse the conversion of phenolic compounds to their respective quinones. Laccases are blue copper enzymes containing four copper atoms/molecule distributed in three different copper binding sites (Pereira et al ., 2005). All these copper ions are apparently involved in the catalytic mechanism.…”