全世界的紡織業(yè)每年要用到大約7×105噸的合成染料，而其中5萬噸都會被釋放到環(huán)境中,，這些人工合成染料不僅污染水質(zhì),，而且破壞光線的穿透、影響氣體的溶解,。含氮物,、蒽醌和靚藍(lán)是染料中的主要發(fā)色體，用物理和化學(xué)方法對發(fā)色體進(jìn)行破壞受到了經(jīng)濟(jì)可行性及方法上的限制,，因而目前研究多集中于采用生物酶法,。
意大利的研究者Fabrizio Briganti等分析了F.trogii菌分泌出的氧化還原酶對幾種常用染料的脫色效果，以及聯(lián)合使用纖維二糖還原酶（CDH）或者漆酶的氧化還原介體對最頑固的染料的脫色效果,。
通過研究F.trogii菌的生長曲線及優(yōu)化條件,，得出在培養(yǎng)菌株8~9天，可以獲得0.6U/ml 的CDH產(chǎn)量和5~6 U/ml的漆酶酶活,。分別用粗酶液與純化后的漆酶在pH=3.0和pH=7.0時,，對幾種常用染料進(jìn)行酶解脫色處理,。結(jié)果表明，pH=7.0時,，對幾乎所有染料的脫色效果都很好,，盡管此時的漆酶酶活較之于在pH=3.0時有了較大的降低，分析原因可能是因為pH=7.0時待測染料的溶解度最高,。接著,，又用添加了羥基苯并三唑（HBT）介體的漆酶液對以粗酶液處理脫色效果不明顯的染料進(jìn)行了脫色處理實驗。漆酶/HBT體系比單純使用漆酶在氧化染料發(fā)色基團(tuán)上更有效,，因為HBT是比漆酶更強(qiáng)的氧化劑,，因而可以使某些比較頑固的染料氧化脫色。
CDH因為可以間接地產(chǎn)生強(qiáng)氧化性的羥基基團(tuán),，因而具有替換昂貴的化學(xué)介體物質(zhì)（如HBT）的潛力,。通過在漆酶中添加CDH和30mM的乳糖（乳糖是激發(fā)CDH產(chǎn)生氧化性羥基基團(tuán)的必需物質(zhì)），對Reactive Red 272染料的脫色效力增強(qiáng)了4.3倍,，同時,，對蒽醌類染料的脫色效色也有很大的提高。
因而,，將漆酶粗酶液或漆酶與CDH的混合酶液直接用在需要昂貴的化學(xué)處理及合成介體的染料脫色處理場合,，將是未來處理廢染料的發(fā)展趨勢。相關(guān)論文發(fā)表在愛思唯爾期刊《生物資源技術(shù)》（Bioresource Technology）上,。（生物谷Bioon.com）
生物谷推薦原始出處：
Bioresource Technology,，Volume 99, Issue 15, October 2008, Pages 7003-7010，Ilaria Ciullini,，F(xiàn)abrizio Briganti
Fungal laccase, cellobiose dehydrogenase, and chemical mediators: Combined actions for the decolorization of different classes of textile dyes
Ilaria Ciullinia, Silvia Tillia, Andrea Scozzafavaa and Fabrizio Briganti, a,
Abstract
Dyes belonging to the mono-, di-, tri- and poly-azo as well as anthraquinonic and mono-azo Cr-complexed classes, chosen among the most utilized in textile applications, were employed for a comparative enzymatic decolorization study using the extracellular crude culture extracts from the white rot fungus Funalia (Trametes) trogii grown on different culture media and activators able to trigger different levels of expression of oxidizing enzymes: laccase and cellobiose dehydrogenase. Laccase containing extracts were capable to decolorize some dyes from all the different classes analyzed, whereas the recalcitrant dyes were subjected to the combined action of laccase and the chemical mediator HBT, or laccase plus cellobiose dehydrogenase. Correlations among the decolorization degree of the various dyes and their electronic and structural diversities were rationalized and discussed. The utilization of cellobiose dehydrogenase in support to the activity of laccase for the decolorization of azo textile dyes resulted in substantial increases in decolorization for all the refractory dyes proving to be a valid alternative to more expensive and less environmentally friendly chemical treatments of textile dyes wastes.
