KINETIC STUDY OF BIODEGRADATION OF TEXTILE DYESTUFFS BY WHITE ROT FUNGI

Abstract

Potentials of five locally isolated white rot fungi Pleurotus ostreatsus IBL-02, Phanerochaete chrysosporium IBL-03, Coriolus versicolor IBL-04, Ganoderma lucidum IBL-05, and Schizophyllum commune IBL-06, for biodegradation of textile dyes commonly used in Fasalabd texile dyeing process units, were investigated. Dyes (Reactive, Disperse, Direct and Vat) dyes were provided free of cost from Clarient (pvt) limited, Ciba (pvt) limited and Dyestar (pvt) limited. Reactive dyes included Drimarine Blue K2RL, Cibacron blue FG3A, Drimarine Orange KGL, Drimarine Brilliant Red K4BL, Prucion Blue PX5R, and Remazol Brilliant Yellow 3G. The dyes of disperse class were Foron Turquize SBLN-200, Foron Blue RDGLN, Foron Red RDRBLS and Foron Yellow SE4G. Direct dyes group comprised of Solar Golden Yellow R, Solar Brilliant Red BA, Solar Orange RSN and Solar Blue A and Vat dyes included were Cibanon Blue BFMD, Cibanon Golden Yellow RK-MD, Indanthrene Direct Black RBS. White Rot fungi cultures were applied on reactive dyes and a combination of best fungus and best decolorized dye was selected. Reactive Remazole Brilliant Yello3-GL was maximally decolorized by coriolus versicolor in 7 days of incubation and it was processed for further process optimization. Activities of LiP, MnP and laccase were124, 254 and 354 IU/mL were respectively. The C. versicolor strain decolorized 0.01% dye up to 99.6% in 24 hours in Kirk’s medium, I; pH, 4, temperature, 30±20C with the addition of 1% Glucose, 0.1% CSL, 1mM ABTS and CuSO4. Activities of MnP and laccase were 389 and 795 IU/Ml. Adsorption on fungal mycelia was negligible in 0.01 % dye solution but it increased with higher dye the concentration. Disperse dyes were also subjected to decolorization by WRF cultures and maximum decolorization (91.87%) of Foron Turquoise SBLN-200 was caused by Ganoderma lucidumon on 8th day. After optimization of varying media ompositions the dye was effectively decolorized in medium IV which was nitrogen rich and its lignolytic enzyme profile was 282, 115 and 116 IU/mL for LiP, MnP and laccase respectively on 7th day of incubation. Further process of optimization revealed that 99.20% dye was degraded in solution receiving 0.01% dye concentration with production of LiP, MnP nand laccase (636, 531and 382 IU/mL respectiely) under optimum conditions (MediumIV; pH 4.5, temperature, 35±20C, in the presence of 1.5%wheat bran, 0.1% of MGM60%, 1mM Veratryl Alcohol and 1mM MnSO4). Direct dyes like reactive and disperse were subjected to decolorization by WRF and screening experiment proved that Pleurotus ostreatus was efficient in decolorizing Solar Golden Yellow R up to 93.10% in 7 days. After optimization of media composition the dye color removal reached at 98.86% in MediumIII and activities of Lip,MnP, AND laccase were 61,163 and 140 IU/ML respectively. Uner Complete optimum conditions ( at pH 3.5 and temperature 30±20C in presene of 1.0% Wheat Bran, 0.05% of MGM (60%), 1Mm of H2O2 and FeSO4 maximum dye decolorization was achieved in 24 hours of incubation. Activities of major enzymes MnP and Lac were 687 and 376 IU/mL respectively. Dye adsorption was negligible. Vat dyes usually were not soluble in water and dye solution were prepared in dilute NaOH. sluccinic Acid was used to adjust optimum pH. Of all WRF cultures applied on vat dyes, C.versicolor showed maximum decolorization (92.32%) of Cibanon Blue GFJ-MD in 6 days of incubation in Kirk’s basal medium. After media compositions optimization the dye was degraded up to 97.12% in medium II and enzyme activies were 54, 35 and 185 IU/m. After the completion of process optimization medium II ; pH, 4 ; temperature, 30±20C; Glucose, 1%; 1m M ABTS and CuSO4. 0.01% Cibanon Blue GFJ- MD was degraded up to 99.12% in 24 hours. Major enzyme involved in dye degradation was laccase and its was 595 IU/mL. Dye adsorption was 0.06% after 24 hours of incubation which declined with the passage of time, due to degradation of dyes by the enzymes. Addition of nitrogen showed inhibitory effect on fungal enzyme activities and dye removal.