Qin Siqi, Li Qiao, Wu Liuyan, Tian Hongmei, Man Yuanyuan, Liu Guofang
Guangxi Key Laboratory for Polysaccharide Materials and Modifications, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning, Guangxi, 530006, China.
Shenzhen QS SynBio Sci-Tech Co. Ltd., Shenzhen, Guangdong, 518107, China.
Sci Rep. 2025 Jul 2;15(1):23577. doi: 10.1038/s41598-025-08584-0.
A bacterium showing excellent flocculation performance was isolated from sludge. Through 16S rDNA sequencing, morphological observation, and enzyme characterization, the strain was found to represent a novel bacterium of the Pseudomonas sp., termed Pseudomonas sp. GXUN74702. Pseudomonas sp. GXUN74702 was isolated from the sludge of Siyuan Lake in Guangxi Minzu University. Research showed that strain GXUN74702 had good flocculation performance. After the strain was cultured in fermentation medium (pH 7.0) containing glucose as carbon and urea as nitrogen, shaking at 30 °C 180 rpm for 36 h, the flocculation rate reached 92.5% when treating kaolin suspension with 2 mL of the fermentation broth. The microbial flocculants (MBF) GXUN74702 contained 78.90% total sugars and 6.78% protein. Ion chromatography detection showed that the monosaccharide constituents of MBF-GXUN74702 were most mannose (10.55 µg/mg), glucose (5.34 µg/mg), and glucosamine hydrochloride (1.48 µg/mg). The use of MBF-GXUN74702 for treating aquaculture wastewater was then explored, demonstrating chemical oxygen demand (COD) and biochemical oxygen demand (BOD) removal rates of 52% and 20%, respectively. In summary, Pseudomonas sp. GXUN74702 is a newly identified Pseudomonas sp. strain that shows highly efficient flocculation performance in treating aquaculture wastewater, suggesting its potential value in wastewater treatment applications. The fermentation medium components of Pseudomonas sp. GXUN74702 identified in this study are simple and easy to obtain, and the fermentation conditions of the strain are mild and not harsh, so a large number of fermentation liquid with high flocculation performance can be obtained in a short time. The main component of MBF-GXUN74702 has been proved to be polysaccharides that are superior to inorganic and synthetic organic flocculants owing to their non-toxicity, biodegradability, high efficiency, free secondary pollution, and wide adaption to pH variation. At present, the team has obtained the flocculants powder of the strain under laboratory conditions. The production process of this powder is simple, the yield and flocculation rate are high, and the property is stable and easy to preserve.
从污泥中分离出一株具有优异絮凝性能的细菌。通过16S rDNA测序、形态学观察和酶学特性分析，发现该菌株代表假单胞菌属的一种新型细菌，命名为假单胞菌GXUN74702。假单胞菌GXUN74702从广西民族大学思源湖的污泥中分离得到。研究表明，菌株GXUN74702具有良好的絮凝性能。将该菌株在以葡萄糖为碳源、尿素为氮源的发酵培养基（pH 7.0）中，于30℃、180 rpm振荡培养36 h后，取2 mL发酵液处理高岭土悬浮液，絮凝率达到92.5%。微生物絮凝剂（MBF）GXUN74702中总糖含量为78.90%，蛋白质含量为6.78%。离子色谱检测表明，MBF-GXUN74702的单糖成分主要为甘露糖（10.55 μg/mg）、葡萄糖（5.34 μg/mg）和盐酸氨基葡萄糖（1.48 μg/mg）。随后探索了MBF-GXUN74702用于处理水产养殖废水的效果，结果表明其化学需氧量（COD）和生化需氧量（BOD）的去除率分别为52%和20%。综上所述，假单胞菌GXUN74702是一种新鉴定的假单胞菌属菌株，在处理水产养殖废水方面表现出高效的絮凝性能，表明其在废水处理应用中的潜在价值。本研究确定的假单胞菌GXUN74702的发酵培养基成分简单易获取，菌株的发酵条件温和不苛刻，因此可在短时间内获得大量具有高絮凝性能 的发酵液。已证明MBF-GXUN74702的主要成分是多糖，与无机和合成有机絮凝剂相比，多糖具有无毒、可生物降解、高效、无二次污染以及对pH变化适应性广等优点。目前，该团队已在实验室条件下获得了该菌株的絮凝剂粉末。该粉末的生产工艺简单，产量和絮凝率高，性质稳定且易于保存。
