Production of Ligninolytic Enzymes by White-Rot Fungus<i>Datronia</i>sp. KAPI0039 and Their Application for Reactive Dye Removal

Abstract

This study focused on decolorization of 2 reactive dyes; Reactive Blue 19 (RBBR) and Reactive Black 5 (RB5), by selected white-rot fungus Datronia sp. KAPI0039. The effects of reactive dye concentration, fungal inoculum size as well as pH were studied. Samples were periodically collected for the measurement of color unit, Laccase (Lac), Manganese Peroxidase (MnP), and Lignin Peroxidase (LiP) activity. Eighty-six percent of 1,000 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mtext>mg L</mml:mtext><mml:mrow><mml:mo>−</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:math>RBBR decolorization was achieved by 2% (w/v) Datronia sp. KAPI0039 at pH 5. The highest Lac activity (759.81 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mtext>UL</mml:mtext><mml:mrow><mml:mo>−</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:math>) was detected in the optimal condition. For RB5, Datronia sp. KAPI0039 efficiently performed (88.01% decolorization) at 2% (w/v) fungal inoculum size for the reduction of 600 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mtext>mg L</mml:mtext><mml:mrow><mml:mo>−</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:math>RB5 under pH 5. The highest Lac activity (178.57 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mtext>UL</mml:mtext><mml:mrow><mml:mo>−</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:math>) was detected, whereas the activity of MnP and LiP was absent during this hour. The result, therefore, indicated that Datronia sp. KAPI0039 was obviously able to breakdown both reactive dyes, and Lac was considered as a major lignin-degradation enzyme in this reaction.