Department of Water and Sanitation, University of Limpopo, Private Bag X1106, Polokwane 0727, South Africa.
Department of Biochemistry, Microbiology and Biotechnology, University of Limpopo, Private Bag X1106, Polokwane 0727, South Africa.
Int J Environ Res Public Health. 2022 Aug 18;19(16):10237. doi: 10.3390/ijerph191610237.
The application of bioflocculants has become an alternative to that of chemical flocculants in wastewater treatment due to their environmental friendliness and non-toxic effects. This study aimed at isolating a bioflocculant-producing bacterium from marine water, optimisation of its culture conditions, and investigation of the removal efficiency of its bioflocculant on pollutants in wastewater. The bacterium was identified by 16S rRNA gene analysis. Optimal carbon and nitrogen sources, inoculum size, temperature, pH, and time were determined by the one-factor-at-a-time assay. The cytotoxicity of the bioflocculant was assessed on African green monkey kidney and bovine dermis cells using a tetrazolium-based columetric (MTT) method. Its removal efficiencies on chemical oxygen demand (COD), biological oxygen demand (BOD) and sulphur were determined using the Jar test method. The bacterial isolate was identified as AB84113. A maximum flocculating activity of 92% and a yield of 3.768 g/L were obtained when a 1% (/) inoculum size was used in the presence of starch and yeast extract at pH 7, 30 °C, and after 72 h of cultivation. The bioflocculant demonstrated non-cytotoxic effects on bovine dermis and African green monkey kidney cells. The bioflocculant removed 98% COD, 91% BOD and 86% of Sulphur. The bioflocculant has potential for pollutant removal from industrial wastewater.
由于生物絮凝剂具有环境友好和无毒的作用，因此在废水处理中已成为化学絮凝剂的替代品。本研究旨在从海水中分离出一种产生生物絮凝剂的细菌，优化其培养条件，并研究其生物絮凝剂对废水中污染物的去除效率。通过 16S rRNA 基因分析鉴定细菌。通过单因素实验确定最佳碳源和氮源、接种量、温度、pH 值和时间。采用基于噻唑蓝的比色（MTT）法评估生物絮凝剂对非洲绿猴肾和牛真皮细胞的细胞毒性。采用Jar 试验法测定其对化学需氧量（COD）、生物需氧量（BOD）和硫的去除效率。细菌分离株被鉴定为 AB84113。当在 pH 7、30°C 下培养 72 小时，使用 1%（/）接种量，并存在淀粉和酵母提取物时，絮凝活性最高可达 92%，产量为 3.768 g/L。生物絮凝剂对牛真皮和非洲绿猴肾细胞无细胞毒性作用。生物絮凝剂去除了 98%的 COD、91%的 BOD 和 86%的硫。生物絮凝剂具有从工业废水中去除污染物的潜力。
