title: Natural and synthetic hormone removal using the horseradish peroxidase enzyme: temperature and pH effects.
abstract: The primary objective of our research was to establish the technical feasibility of using the horseradish peroxidase (HRP) enzyme for natural and synthetic estrogens-estrone (E1), 17beta-estradiol (E2), estriol (E3), and 17alpha-ethinylestradiol (EE2)-removal. The effects of temperature and pH on enzymatic treatment kinetics were investigated. Residual estrogen concentrations were quantified by liquid chromatography, coupled with mass spectrometry analysis. In a synthetic solution at pH 7 and 25+/-1 degrees C, the HRP enzyme-catalyzed process was capable of achieving 92-100% removal of E1, E2, E3, and EE2 within 1h of treatment with an HRP activity of 0.017 U/ml. The influence of the pH (5-9) and temperature (5-35 degrees C) on estrogen removal was observed to be significant, with the optimum pH near neutral conditions. The results also showed that wastewater constituents significantly impact the HRP-catalyzed estrogen removal. The experimental research proved that the HRP-catalyzed system is technically feasible for the removal of the main estrogens present in the environment at low concentrations.
authors.affiliation: University of Missouri-Rolla, Environmental Research Center for Emerging Contaminants, 220 Butler Carlton Hall, 65409, USA.
authors.forename: Muriel
authors.initials: M
authors.lastname: Auriol
authors.forename: Youssef
authors.initials: Y
authors.lastname: Filali-Meknassi
authors.forename: Craig D
authors.initials: CD
authors.lastname: Adams
authors.forename: Rajeshwar D
authors.initials: RD
authors.lastname: Tyagi
mesh_terms: D002384:Catalysis; D003124:Colorimetry / Q000379:methods; D004958:Estradiol / Q000032:analysis; D004964:Estriol / Q000032:analysis; D004970:Estrone / Q000032:analysis; D004997:Ethinyl Estradiol / Q000032:analysis; D006728:Hormones / Q000032:analysis*; D006735:Horseradish Peroxidase / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008956:Models, Chemical; D013696:Temperature; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
chemical_list: D006728:Hormones; D014874:Water Pollutants, Chemical; D004970:Estrone; D004997:Ethinyl Estradiol; D004958:Estradiol; D006735:Horseradish Peroxidase; D004964:Estriol