Isolation of 2 simazine-degrading bacteria and development of a microbial agent for bioremediation of simazine pollution

Abstract

Simazine was one of the most commonly used herbicides and was widely used to control broadleaf weeds in agriculture and forestry. Its widespread use had caused wide public concern for its high ecological toxicity. In order to remove simazine residues, 2 strains capable of effectively degrading simazine were isolated from the soil and named SIMA-N5 and SIMA-N9. SIMA-N5 was identifi ed as Bacillus licheniformis by 16SrRNA sequence analysis, and SIMA-N9 was Bacillus altitudinis. According to the degradation ratio of simazine in a certain period of time, the degradation ability of different strains was evaluated. The degradation effi ciency of simazine (5 mg/L) by SIMA-N9 could reach about 98% in 5d, and the strain SIMA-N5 could reach 94% under the same conditions. In addition, the addition of Pennisetum rhizosphere soil during the process of degrading simazine by strain SIMA-N9 could effectively improve the degradation effi ciency. The strain SIMA-N9 has been developed as a microbial agent for the bioremediation of simazine contamination in soil. The new microbial agent developed by using SIMA-N9 has achieved satisfactory application effects. Based on the research results already obtained in this study, it was considered that strain SIMA-N9 and its live bacterial agent could play an important role in bioremediation of simazine pollution. This study could not only provide a set of solutions to the simazine pollution, but also provide a reference for the treatment of other pesticide pollution.

Research on a Biofilter for a Typical Application Scenario in China: Treatment of Pesticide Residue Wastewater in Orchards

“…Alternatively, the degradation efficiency may have been enhanced because the biomixture strongly affected the pesticide via adsorption and degradation, and the biofilter system consisted of four biofiltration units. Furthermore, the substrate from biomixture contained microbial agents, and some research has confirmed that microbial agents had an important impact on pesticide residue degradation and microbial remediation in the soil [34,35]. Therefore, they could be bioaugmentation agents, which could enhance the degradation efficiency of pesticides from the biofilter system.…”

Development of solid agents of the diphenyl ether herbicide degrading bacterium Bacillus sp. Za based on a mixed organic fertilizer carrier

“…However, liquid agents often have a short shelf life and show unstable effects ( Wen et al, 2021 ). Compared with liquid agents, solid ones have many advantages, such as easy storage and transport, a longer action time, the protection of degrading bacteria from environmental influences, and the provision of a suitable microenvironment for bacterial survival ( Ruan et al, 2018 ; Zhu et al, 2021 ). There have been some reports on the commercialization of high-efficiency degrading strains for the remediation of soil and water ( Sayed and Behle, 2017a ; Mohd Yusof et al, 2019 ).…”