National Engineering Laboratory for Deep Process of Rice and Byproducts, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China.
National Engineering Laboratory for Deep Process of Rice and Byproducts, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China; College of Life Sciences and Chemistry, Hunan University of Technology, Zhuzhou, Hunan, 412007, Hunan, China.
Environ Pollut. 2022 Jan 1;292(Pt A):118306. doi: 10.1016/j.envpol.2021.118306. Epub 2021 Oct 8.
Slaughter wastewater is an important and wide range of environmental issues, and even threaten human health through meat production. A high efficiency and stability microsphere-immobilized Bacillus velezensis strain was designed to remove organic matter and inhibit the growth of harmful bacteria in process of slaughter wastewater. Bacillus velezensis was immobilized on the surface of sodium alginate (SA)/Polyvinyl alcohol (PVA)/Nano Zinc Oxide (Nano-ZnO) microsphere with the adhesion to bio-carrier through direct physical adsorption. Results indicated that SA/PVA/ZnO and SA/ZnO microspheres could inhibit E.coli growth with adding 0.15 g/L nano-ZnO and not affect Bacillus velezensis strain, and the removal the chemical oxygen demand (COD) rates of SA/PVA/ZnO microsphere immobilized cells are 16.99%, followed by SA/ZnO (13.69%) and free bacteria (7.61%) from 50% concentration slaughter wastewater within 24 h at 37 °C, pH 7.0, and 120 rpm, a significant difference was found between the microsphere and control group. Moreover, when the processing time reaches 36 h, COD degradation of SA/PVA/ZnO microsphere is obviously higher than other groups (SA/PVA/ZnO:SA/ZnO:control vs 18.535 : 15.446: 10.812). Similar results were obtained from 30% concentration slaughter wastewater. Moreover, protein degradation assay was detected, and there are no significant difference (SA/PVA/ZnO:SA/ZnO:control vs 35.4 : 34.4: 36.0). The design of this strategy could greatly enhance the degradation efficiency, inhibit the growth of other bacteria and no effect on the activity of protease in slaughter wastewater. These findings suggested that the nano-ZnO hydrogel immobilization Bacillus velezensis system wastewater treatment is a valuable alternative method for the remediation of pollutants from slaughter wastewater with a novel and eco-friendly with low-cost investment as an advantage.
屠宰废水是一个重要且广泛存在的环境问题，甚至会通过肉类生产威胁到人类健康。本研究设计了一种高效稳定的固定化蜡状芽孢杆菌微球，用于去除屠宰废水中的有机物并抑制有害细菌的生长。通过直接物理吸附，将蜡状芽孢杆菌固定在海藻酸钠（SA）/聚乙烯醇（PVA）/纳米氧化锌（Nano-ZnO）微球表面，实现生物载体的附着。结果表明，添加 0.15 g/L 纳米 ZnO 的 SA/PVA/ZnO 和 SA/ZnO 微球可以抑制大肠杆菌的生长，且不影响蜡状芽孢杆菌的生长，并且在 37°C、pH 7.0 和 120 rpm 条件下，50%浓度屠宰废水中，SA/PVA/ZnO 微球固定细胞的化学需氧量（COD）去除率在 24 h 内分别达到 16.99%，随后是 SA/ZnO（13.69%）和游离菌（7.61%），差异显著。此外，当处理时间达到 36 h 时，SA/PVA/ZnO 微球的 COD 降解明显高于其他组（SA/PVA/ZnO:SA/ZnO:对照=18.535:15.446:10.812）。在 30%浓度的屠宰废水中也得到了类似的结果。此外，还检测了蛋白质降解试验，结果无显著差异（SA/PVA/ZnO:SA/ZnO:对照=35.4:34.4:36.0）。该策略的设计可以大大提高降解效率，抑制其他细菌的生长，且对屠宰废水中蛋白酶的活性无影响。这些发现表明，纳米 ZnO 水凝胶固定化蜡状芽孢杆菌系统处理废水是一种有价值的替代方法，可用于修复屠宰废水污染物，具有新颖、环保和低成本投资的优势。
