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Degradation Performance of Estrogen During Anaerobic Digestion of Pig Manure

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Abstract

A large amount of estrogen is introduced into the feed to improve livestock growth, excessive residual estrogen would exist in the excrements. The accumulation of estrogen can cause the water and soil pollution around the farm, further inhibit growth and induce caner for organisms and human. Anaerobic digestion (AD) could effectively remove estrogen in livestock manure while the mechanism is still unclear. In this study, the mechanism of estrogen removal by AD was explored during AD process of pig manure. Estrone (E1), estradiol (E2) estriol (E3) and ethinylestradiol (EE2) were selected as research subjects. The removal rates of E1, E2, E3 and EE2 were 19.14, 28.62, 25.83 and 11.81%. Dissolved organic matters (DOM), especially humic acid, play an important role in reducing bioavailability of estrogen. Estrogen will be absorbed by DOM through structures such as aromatic ring and amides. Estrogen may also promote the growth of microorganisms which could degrade estrogen, such as Rhodococcus, Sphingomonas and Pseudomonas. The amount of these microorganisms and dissolved microbial metabolites did not change obviously. This study would give a new explanation for the removal of estrogen and can provide theoretical support for harmless treatment of pig manure.

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Data Availability

The datasets generated and analyzed during the current study are not publicly available due to time limitations but are available from the corresponding author on reasonable request.

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Acknowledgements

This work was supported by School of Environmental and Engineering, Changzhou University. The authors would like to thank School of Environmental and Engineering, Changzhou University for their effort in laboratory works.

Funding

This research was supported by “Research on key technologies for co-production of organic fertilizers from bio methanol based on biogas and green hydrogen” and “Postgraduate Research and Practice Innovation Program of Jiangsu Province” (grant number BE2022426 and SJCX22_1383).

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  1. School of Environmental Science and Engineering, Changzhou University, Gehu Middle Road 21, Changzhou City, 213164, China

    Xiaoliang Luo, Bincheng Zhao, Junwen Yao, Mingguo Peng, Linqiang Mao, Wenyi Zhang & Rongyan Shen

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  1. Xiaoliang Luo
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  2. Bincheng Zhao
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All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by BZ, JY. The first draft of the manuscript was written by XL and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

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Correspondence to Linqiang Mao.

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Luo, X., Zhao, B., Yao, J. et al. Degradation Performance of Estrogen During Anaerobic Digestion of Pig Manure. Waste Biomass Valor 15, 2625–2635 (2024). https://doi.org/10.1007/s12649-023-02286-2

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