title: By-product identification and phytotoxicity of biodegraded Direct Yellow 4 dye.
abstract: Citrus limon peroxidase mediated decolourization of Direct Yellow 4 (DY4) was investigated. The process variables (pH, temperature, incubation time, enzyme dose, H2O2amount, dye concentration, co-metal ions and surfactants) were optimized for maximum degradation of dye. Maximum dye decolourization of 89.47% was achieved at pH 5.0, temperature 50 °C, enzyme dose 24 U/mL, H2O2concentration 0.25 mM and DY4 concentration 18.75 mg/L and incubation time 10 min. The co-metal ions and surfactants did not affect the dye decolourization significantly. Response surface analysis revealed that predicted values were in agreement with experimentally determined responses. The degradation products were identified by UPLC/MS analysis and degradation pathway was proposed. Besides, phytotoxicity assay revealed a considerable detoxification in response of biodegradation of DY4 dye. C. limon showed promising efficiency for DY4 degradation and could possibly be used for the remediation of textile effluents.
authors.affiliation: Department of Chemistry, Women University of Azad Jammu & Kashmir, Bagh, Pakistan. Electronic address: shazianouren@yahoo.com.
authors.forename: Shazia
authors.initials: S
authors.lastname: Nouren
authors.affiliation: Department of Chemistry, University of Agriculture, Faisalabad, Pakistan.
authors.forename: Haq Nawaz
authors.initials: HN
authors.lastname: Bhatti
authors.affiliation: Department of Chemistry, The University of Lahore, Lahore, Pakistan. Electronic address: bosalvee@yahoo.com.
authors.forename: Munawar
authors.initials: M
authors.lastname: Iqbal
authors.affiliation: Department of Chemistry, Islamia University Bahawalpur, Pakistan.
authors.forename: Ismat
authors.initials: I
authors.lastname: Bibi
authors.affiliation: Department of Applied Chemistry, Govt. College University, Faisalabad, Pakistan.
authors.forename: Shagufta
authors.initials: S
authors.lastname: Kamal
authors.affiliation: Bio-analytical Chemistry Laboratory, Punjab Bio-Energy Institute, University of Agriculture, Faisalabad, Pakistan.
authors.forename: Sana
authors.initials: S
authors.lastname: Sadaf
authors.affiliation: Institute of Chemistry, University of the Punjab, Lahore, Pakistan.
authors.forename: Misbah
authors.initials: M
authors.lastname: Sultan
authors.affiliation: Department of Chemistry, Government College Women University, Faisalabad, Pakistan.
authors.forename: Abida
authors.initials: A
authors.lastname: Kausar
authors.affiliation: Department of Chemistry, Lahore College for Women University, Lahore, Pakistan.
authors.forename: Yusra
authors.initials: Y
authors.lastname: Safa
mesh_terms: D001391:Azo Compounds / Q000378:metabolism*; D001557:Benzenesulfonates / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002957:Citrus / Q000187:drug effects* / Q000201:enzymology; D004396:Coloring Agents / Q000633:toxicity*; D013058:Mass Spectrometry; D010544:Peroxidases / Q000378:metabolism*
chemical_list: D001391:Azo Compounds; D001557:Benzenesulfonates; D004396:Coloring Agents; C059622:Direct Yellow 4 dye; D010544:Peroxidases
keywords: Central composite design; Citrus limon peroxidase; Decolourization; Direct Yellow 4; Dye degradation by-product; Phytotoxicity