title: Reduction in acute ecotoxicity of paper mill effluent by sequential application of xylanase and laccase.
abstract: In order to reduce the ecotoxicity of paper mill, four different enzymatic pretreatment strategies were investigated in comparison to conventional chemical based processes. In strategy I, xylanase-aided pretreatment of pulp was carried out, and in strategy II, xylanase and laccase-mediator systems were used sequentially. Moreover, to compare the efficiency of Bacillus stearothermophilus xylanase and Ceriporiopsis subvermispora laccase in the reduction of ecotoxicity and pollution, parallel strategies (III and IV) were implemented using commercial enzymes. Conventional C(D)E(OP)D(1)D(2) (C(D), Cl(2) with ClO2; EOP, H2O2 extraction; D1 and D2, ClO2) and X/XLC(D)E(OP)D(1)D(2) (X, xylanase; L, laccase) sequences were employed with non-enzymatic and enzymatic strategies, respectively. Acute toxicity was determined by the extent of inhibition of bioluminescence of Vibrio fischeri with different dilutions of the effluent. Two-fold increase was observed in EC50 values for strategy I compared to the control process. On the other hand, sequential application of commercial enzymes resulted in higher acute toxicity compared to lab enzymes. In comparison to the control process, strategy II was the most efficient and successfully reduced 60.1 and 25.8% of biological oxygen demand (BOD) and color of effluents, respectively. We report for the first time the comparative analysis of the ecotoxicity of industrial effluents.
authors: Department of Chemical Engineering, Konkuk University, Gwangjin-Gu, Seoul, Republic of Korea; Institute of SK-KU Biomaterials, Konkuk University, Gwangjin-Gu, Seoul, Republic of Korea.
authors: Saurabh Sudha
authors: SS
authors: Dhiman
authors: Department of Biotechnology, Kurukshetra University, Kurukshetra, Haryana, India; Department of Biotechnology, Maharishi Markandeshwar University, Mullana-Ambala, Haryana, India.
authors: Gaurav
authors: G
authors: Garg
authors: Department of Biotechnology, Kurukshetra University, Kurukshetra, Haryana, India.
authors: Jitender
authors: J
authors: Sharma
authors: Microbial Biotechnology and Genomics, CSIR-Institute of Genomics and Integrative Biology, Delhi University Campus, Delhi, India.
authors: Vipin C
authors: VC
authors: Kalia
authors: Department of Chemical Engineering, Konkuk University, Gwangjin-Gu, Seoul, Republic of Korea.
authors: Yun Chan
authors: YC
authors: Kang
authors: Department of Chemical Engineering, Konkuk University, Gwangjin-Gu, Seoul, Republic of Korea; Institute of SK-KU Biomaterials, Konkuk University, Gwangjin-Gu, Seoul, Republic of Korea.
authors: Jung-Kul
authors: JK
authors: Lee
mesh_terms: D048908:Aliivibrio fischeri / Q000187:drug effects / Q000502:physiology; D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D057919:Biological Oxygen Demand Analysis; D055453:Coriolaceae / Q000737:chemistry / Q000201:enzymology; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry* / Q000302:isolation & purification; D005656:Fungal Proteins / Q000737:chemistry* / Q000302:isolation & purification; D001411:Geobacillus stearothermophilus / Q000737:chemistry / Q000201:enzymology; D006861:Hydrogen Peroxide / Q000737:chemistry; D007220:Industrial Waste; D042845:Laccase / Q000737:chemistry* / Q000302:isolation & purification; D010209:Paper; D014874:Water Pollutants, Chemical / Q000037:antagonists & inhibitors* / Q000633:toxicity
chemical_list: D001426:Bacterial Proteins; D005656:Fungal Proteins; D007220:Industrial Waste; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; D042845:Laccase; D043364:Endo-1,4-beta Xylanases