Biodegradation of Atrazine by Mixed Bacteria of Klebsiella variicola Strain FH-1 and Arthrobacter sp. NJ-1

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Biodegradation of Atrazine by Mixed Bacteria of Klebsiella variicola Strain FH‑1 and Arthrobacter sp. NJ‑1 Ning Gao1 · Jinpeng Zhang1 · Zequn Pan1 · Xiaofeng Zhao1 · Xiulan Ma2 · Hao Zhang1  Received: 27 May 2020 / Accepted: 13 August 2020 © Springer Science+Business Media, LLC, part of Springer Nature 2020

Abstract The purpose of this study is to enhance the biodegradability of atrazine with FH-1 and NJ-1 alone by selecting the mixing ratio, optimizing the culture medium and conditions. The results showed that FH-1 and NJ-1 have the best biodegradation effect on atrazine being mixed in a volume ratio of 3:2. In a single factor experiment, sucrose and ­NH4Cl provided carbon and nitrogen sources for the mixed bacteria. Subsequently, composition of fermentation medium was further optimized using Box-Behnken design of response surface methodology. Based on the results, growth of mixed bacteria and biodegradation of atrazine performed best effects with a biodegradation rate of 85.6% when sucrose and N ­ H4Cl amounts were 35.30 g/L and 10.28 g/L. The optimal medium condition was 10% inoculum of mixed bacteria, with initial atrazine concentration of 50 mg/L, neutral or weakly alkaline pH value, 30°C. The biodegradation rate reached 97.4%, 11.8% higher than the unoptimized condition. Keywords Atrazine · Klebsiella variicola strain FH-1 · Arthrobacter sp. NJ-1 · Biodegradation · Box-Behnken design Atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5triazine) is a selective triazine herbicide (Smith et al. 2005), mainly used to control annual grass weeds and broad-leaved weeds in corn, sugar cane, sorghum fields and other crop fields (Lin et al. 2019), which has become one of the most popular herbicides in the world due to its high efficiency, low Ning Gao and Jinpeng Zhang shared equally in first-authorship. * Hao Zhang [email protected] Ning Gao [email protected] Jinpeng Zhang [email protected] Zequn Pan [email protected] Xiaofeng Zhao [email protected] Xiulan Ma [email protected] 1



College of Plant Protection, Jilin Agricultural University, Changchun 130118, China



College of Resource and Environment, Jilin Agricultural University, Changchun 130118, China

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toxicity, low cost and wide application (Hansen et al. 2019). On the other hand, it has caused pollution of many soils and groundwater because of its strong leaching and long residue characteristics (Zaya et al. 2011). Due to the different physical and chemical properties of the soil, the halfperiod of atrazine varies from 1 to 12 months, which has a certain phytotoxicity effect on subsequent crops (Zhang et al. 2014a, b), also has multiple toxic effects on fish, algae, insects, aquatic plants and mammals (Shenoy 2014; Baxter et al. 2016). Residual atrazine and its related metabolites not only interfere with the endocrine of humans and animals, but also threaten the stability of the ecosystem (Murphyam et al. 2006). Many methods have been used to remove atrazine from the environment, including chemical treatment, adsorption, incineration and microb