PRODUCTION CHARACTERIZATION AND DE-COLORIZATION OF ANTHRAQUINONE DYE BY LACCASE FROM ISOLATED GANODERMA LUCIDUM UPAG08
Khanchai Danmek, Somchart Thana and Choke Sorachakula
Abstract
The production of laccase by Tropical Mushroom Ganoderma lucidum UPAG08 isolated in Thailand by Semi-synthethic (SS) medium cultivation under static culture condition at 30 OC was investigated. Response Surface Methodology (RSM) was used for production and of laccase. Laccase yield (mU/ml) was significantly (p0.05) increased when incubation day and number of mycelia agar plug increased while the number of supporter had no significant influence on laccase production by G. lucidum UPAG08. The model showed the maximum laccase yield appeared at 16.36 days and 21 pieces of mycelia agar plug and 20 pieces of growth support matrix. When both sorbitol and casein were used as the sole carbon and nitrogen source respectively, the laccase activity was 306.909.12 mU/ml which was 2.13 fold greater than the control medium containing glucose, yeast extract and peptone (143.9915.20). The enzyme retained more than 50% of residual activity, even after 48 hr of incubations in pH between 4.5 to 6.5. The kinetic parameters Km and Vmax indicate that 2, 2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) is a preferred specific substrate for laccase activity when compared to 2, 6-Dimethylphenol (2, 6-DMP). The reaction of crude laccase (20 mU) supplemented with ABTS showed capacity to de-colorized Remazol Brilliant Blue R dye (RBBR) in 51.146.53%. The results suggest that crude laccase from G. lucidum UPAG08 have potential use as biological pretreatment of anthraquinone dye of RBBR.