Study On Horseradish Peroxidase Catalyzed Oxidation Of 17β-estradiol

Environment hormones are kind of chemicals similar to estrogen hormones which are able to disrupt the endocrine of the biology by entering into their bodies. So far, about 70 kind of chemicals, which are considered as Environment hormones substances, have shown estrogenic activity to the different extent. For example,alkyl hydroxybenzene, 17β-estrodiol(E2), BPA, E1, DES, EE2, and so on. During these steroid substances,E2 is detected in the water system which is of highly estrogenic activity in the recent years. Even in the concentration of 0.001μmol/L,it can induce the abnormality of the procreation system and endocrine system, such as decreasing the biologic procreation ability, making life-form female, increasing the probability in suffering uterine cancer, ovary cancer and galactophore cancer. Accordingly,E2 has been deemed to endocrine-disrupting substance of highly estrogenic activity, which is from the human and animal excrement.The article recites the techniques of 17β-estrdiol disposal, and then analyses the limitation of these techniques in actual application. And the text also summarizes the strongpoints of the enzyme-catalyze technique, introduces the application of Horseradish Peroxidase(HRP) in industrial wastewater disposal, and explains the mechanism in the disposal of phenol and its ramifications by HRP. Grounded on these theories, the experiments of HRP catalyze oxidation of E2 are designed. The reaction system where H₂O₂ is used as the oxidizer, is set up based upon the highly catalyze oxidation ability of HRP on phenol and its ramifications. During the experimentation, constant temperature surge incubator is used for actualizing the condition of the temperature and continuous surge. The influential factors on the efficiency of the disposal of E2 in these experiments have been study, for instance, temperature, pH, concentration of HRP, dosage of H₂O₂, and the beginning content of E2.The results lay a foundation for the subsequent research, e.g. establishing the dynamics model of the reaction, forecasting the mechanism of the reaction, investigating the efficiency of the actual application of HRP catalyze oxidation of E2 in the wastewater. The results also provide the basis for the catalyze oxidation by HRP of other environment hormones, advances a new way of the disposal of wastewater including environment hormones, and affords academic foundation and reliable datum for the establishing of the farther disposal techniques of the wastewater. The work completed is as follows:(1)Set up the reaction system of HRP catalyze oxidation of E2.(2)Study the influential factors on the efficiency of the disposal of E2 in the experiments, e.g. dosage of H₂O₂, pH, temperature, concentration of HRP, and the beginning content of E2.(3)Confirm the best operation condition of the disposal of wastewater including E2 by HRP.The results indicate that HRP can effectively dispose E2 in the wastewater. The suitable pH of the reaction range from 6.2 to 6.7,and relatively better in pH6.5.The suitable temperature of the reaction range from 21.3℃to 28.5℃, and relatively better in 25℃.The suitable ration of M_H2O2 and M_E2 in practice is from 1:1.to 2:1,which is somewhat different from that in theory. Moreover,reaction velocity is related to the dosage of HRP and H₂O₂. The speed of the reaction can be obviously quicken by properly increasing the dosage of HRP,or properly increasing the dosage of H₂O₂.