Pengxin Yu,Guangyu Sun,Lu Xiong,Boying Zheng,Teng Li,Jun Jiang,Yantao Wang,Weiran Yang
Salicylic acid, generally produced by chemical synthesis based on petrochemical products, is a vital organic acid and widely used in the pharmaceutical synthesis. This work developed a new and green route for the production of salicylic acid from biomass-derived 2-furoic acid in two steps. Firstly, 2 mmol 2-furoic acid was creatively converted to 2,3-benzofuran using HZSM-5 (Si/Al=130) at 280 °C for 1.5 h under 100 psi N 2 ; and then the oxidation of 2,3-benzofuran to salicylate was conducted with tert‑ butyl hydroperoxide under basic condition without metal catalyst at 120 °C for 1 h. The stability of the catalyst for the first step and the possible reaction pathway for the second step based on the control experiments was properly envisioned. Regardless of limited salicylic acid yield (16%) from 2-furoic acid, this work paves a potentially feasible pathway for the preparation of drugs from biomass.
The dissemination of antibiotic resistance genes (ARGs) poses global environmental issues, and plasmid-mediated conjugation contributes substantially to the spread of ARGs. Quorum sensing (QS), an important cell–cell communication system that coordinates group behaviors, has potential as a feasible regulation pathway to inhibit the conjugation process. We examined the promoting effects of QS signal on conjugation, and this study is the first to report that QS inhibitors 2(3H)-benzofuranone and acylase I effectively repressed conjugation frequency of RP4 plasmid to 0.32- and 0.13-fold compared with the control respectively. The investigation of underlying mechanisms of QS inhibitors revealed a significant decrease in cellular contact and the formation of transfer channels. The downregulation of sdiA gene regulating the expression of QS signal receptor contribute to conjugation inhibition. Importantly, the expression of genes related to the formation of conjugative pili, which plays a role in plasmid mating bridge formation was downregulated, indicating QS inhibitors affect conjugation mainly through regulation of the mating pair formation system. Furthermore, 2(3H)-benzofuranone and acylase I achieved 84.07% and 66.05% inhibitory effect on plasmid spread in activated sludge reactors. Collectively, our findings demonstrate the feasibility of using different bacteria quorum quenching methods to control the spread of ARGs.
危险品化学品经营许可证（带存储）