Due to high production costs, the popularization and application of microbial flocculants in the field of water treatment have been limited. In this study, the capture of lead ions by the fermentation broth of a novel Paenibacillus sp. strain A9 and cultured with food wastewater was further investigated. The results revealed that the production of MBFA9 could be increased significantly by adding a small amount of carbon and nitrogen to food wastewater. Under the best experimental conditions (pH 8.5, culture temperature 30°C, 150 r/min), adding 1% (m/v) carbon and 0.1% (m/v) nitrogen to 1% (v/v) wastewater resulted in a yield of MBFA9 of 6.29 g/l. At a temperature of 30°C, pH of 5, contact time of 35 min, and FBA9 dosage of 5%, the removal rate and removal capacity of Pb(II) reached the highest values of 95.1% and 317 mg/g, respectively. Field emission scanning electron microscopy analysis indicated that bacterial cells, metabolite small molecule acids, and MBFA9 in FBA9 all contributed to the removal of Pb(II). Fourier-transform infrared spectrometry analysis indicated that functional groups such as –OH, –COOH, –CO, and –NH2 existed in MBFA9 and on the cell surface. Various mechanisms involved in Pb(II) removal can occur simultaneously, including cell surface adsorption, microcrystallization, and biological flocculation.

中文翻译：

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一种新型类芽孢杆菌 A9 菌株生产的微生物絮凝剂，利用食品加工废水代替发酵培养基及其在去除水溶液中 Pb(II) 中的应用

由于生产成本高，微生物絮凝剂在水处理领域的推广应用受到了限制。在这项研究中，一种新型类芽孢杆菌的发酵液对铅离子的捕获。进一步研究了用食品废水培养的菌株 A9。结果表明，在食品废水中加入少量碳和氮，可以显着提高MBFA9的产量。在最佳实验条件下（pH 8.5，培养温度30℃，150 r/min），在1%（v/v）废水中加入1%（m/v）碳和0.1%（m/v）氮，得到MBFA9的产量为6.29克/升。在温度为30°C、pH为5、接触时间为35 min、FBA9用量为5%的条件下，Pb(II)的去除率和去除能力分别达到最高值95.1%和317 mg/g . 场发射扫描电镜分析表明，细菌细胞、代谢物小分子酸和 FBA9 中的 MBFA9 都有助于 Pb(II) 的去除。傅里叶变换红外光谱分析表明，MBFA9 和细胞表面存在–OH、–COOH、–CO 和–NH2 等官能团。涉及 Pb(II) 去除的各种机制可以同时发生，包括细胞表面吸附、微晶化和生物絮凝。