INTERNATIONAL JOURNAL OF BIOASSAYS ISSN: 2278-778X CODEN: IJBNHY ORIGINAL RESEARCH ARTICLE OPEN ACCESS *Corresponding Author: Siddiqui RA, Department Of Microbiology, Government Institute Of Science, Nipat Niranjan Nagar, Caves Road, Aurangabad-431001, Maharashtra, India. 3841 OPTIMIZATION OF LACCASE PRODUCTION FROM POTENTIAL LACCASE PRODUCER ISOLATED FROM MIXED MICROBIAL CULTURE OF DYEING AND TEXTILES EFFLUENT Siddiqui RA 1* , Phatake YB 2 and Dharmadhikari SM 1 1 Department of Microbiology, Government Institute of Science, Aurangabad, Maharashtra, India. 2 Department Of Microbiology, Shardabai Pawar Women’s College, Shardanagar, Baramati, Maharashtra, India. Received for publication: March 05, 2015; Revised: April 21, 2015; Accepted: April 27, 2015 INTRODUCTION Laccases are one of the important enzyme for industrial applications because extensive studies have shown the potential of fungal phenol oxidases as a biological alternative for chemical oxidative processes e.g. pulp delignification, textile industry, food industry, bioremediation, organic synthesis, pharmaceutical sector and nano-biotechnology [Kunamneni et al., 2008b]. Recently, most of the laccase studied are of fungal origin, especially from white-rot fungi, Anthracophyllum discolor [Bustamante et al., 2010], Pycnoporus sanguineus [Eugenio et al., 2009], Trichoderma harzianum [Sadhasivam et al., 2008] etc. In mycology, sequences from the ITS region of the nuclear rDNA are commonly used for the identification of fungi [Koljalg et al., 2005; Naumann et al., 2007; Nilsson et al., 2008]. The ITS sequence including both ITS1 and ITS2, which are separated by the conserved short 5.8S rRNA, has been commonly used to infer phylogenetic relationships of closely related species as well as to assess the variability of a population. Among multiple communities of enzymes, laccases are widely present in the nature and are oldest and most attractive enzymatic system. Laccase (benzenediol: oxygen oxido reductases [EC 1.10.3.2] ) belongs to a group of enzymes called blue copper oxidases, capable of oxidizing phenols and aromatic amines by reducing molecular oxygen to water. They are wide spread in nature and have been found in plants, fungi, bacteria and insects. The objective of this work is to optimize overall process of laccase production, which contributes to develop more effective and economically feasible technology for the treatment of dye industries effluent. Laccase catalyzed the oxidation of variety of organic compound including phenols, methoxy- substituted phenols, amino phenols, diamines and so on (Morozova et al., 2007). They are exceptionally versatile enzymes and majority of laccases are found in white-rot-causing polypores, geophilous saprophytic fungi, as well as some insect and bacteria. In fungi, laccases function in lignin degradation, pathogenesis, detoxification, and morphogenesis. Therefore, laccases produced from fungi have attracted considerable attention of academicians and researchers. The genus Trametes, which belongs to the white-rot fungi, is assumed to be one of the main producers. Among them, Trametes pubescencs has been described as promising laccase producer (Galhaup and Haltrich, 2001). Laccase is so important because it oxidized both the toxic and nontoxic substrates. It plays an important role in food industry, paper and pulp industry, textile industry, synthetic chemistry, cosmetics and soil bioremediation and biodegradation of environmental phenolic pollutant, removal endocrine disruptors (Couto et al., 2006). Along with different application, laccases plays crucial rule in dye de-colorization. Abstract: The laccase enzyme produced by Microorganism was found to be very useful in degradation of synthetic dyes that are commonly found in textile waste, dye industries and lignocelluloseic wastes when used freely or in immobilized form. In the present study for isolation of laccase producing microorganisms sample collected from different forest regions, soil samples near from textile and dye industries and textile waste were used. Out of different bacterial, fungal and actinomycets isolate, one potent Laccase producing fungus namely RS 3 were selected for further study depending upon its high productivity. Using the gene specific sequencing primers, the purified PCR amplicons was sequenced. The sequences were analyzed using Sequencing Analysis 5.2 software. Blast result and phylogenetic tree analysis clearly indicate that fungal strain RS3 is A. nidulans. For the Laccase assay substrate ABTS has been used. The intense brown color development due to oxidation of guaiacol by laccase can be correlated to its activity often read at 420 nm. The process parameters for enzyme production were optimized viz. Carbon source, Nitrogen source, pH and Time of incubation, it was found that Enzyme activity was maximum in basal medium containing starch (Carbon source), Peptone (Nitrogen source) and at pH 5.5 when incubated for 12h (Time of incubation). Key Words: A.Nidulans, Enzyme Optimization, Fungal Laccase, Textile effluent.