INRS-ETE, Université du Québec, 490, Rue de la Couronne, Québec G1K 9A9, Canada.
J Environ Manage. 2013 Oct 15;128:83-91. doi: 10.1016/j.jenvman.2013.04.039. Epub 2013 May 27.
Growth profile and extracellular polymeric substances (EPS) production of Serratia sp.1 was studied in shake flask fermentation for 72 h using wastewater sludge as raw material. Maximum cell concentration of 6.7 × 10(9) cfu/mL was obtained at 48 h fermentation time. EPS dry weight, flocculation activity and dewaterability of different EPS (tightly bound or TB-EPS, loosely bound or LB-EPS and broth-EPS or B-EPS) were also measured. The highest concentration of LB-EPS (2.45 g/L) and TB-EPS (0.99 g/L) were attained at 48 h of fermentation. Maximum flocculation activity and dewaterability (ΔCST) of TB-EPS (76.4%, 14.5s and 76.5%, 15.5s), LB-EPS (67.8%, 8.1s and 64.7%, 7.6s) and broth EPS (61%, 6.1s and 70.4%, 6.8s) were obtained at 36 and 48 h of growth. Higher flocculation activity and dewaterability were achieved with TB-EPS than with the two other EPS. Characterization of TB-EPS and LB-EPS was done in terms of their protein and carbohydrate content. Protein content was much higher in TB-EPS where as carbohydrate content was only slightly higher in TB-EPS than LB-EPS. Morphology of the Serratia strain after fermentation in sludge and TSB was observed under a scanning electron microscope and the cell size was found to be bigger in the sludge medium than the TSB medium.
以废水污泥为原料，在摇瓶发酵 72 小时内研究了斯氏假单胞菌 1 号的生长曲线和胞外聚合物（EPS）的产生。在 48 小时发酵时间内获得了最大细胞浓度 6.7×10(9)cfu/mL。还测量了不同 EPS（紧密结合或 TB-EPS、松散结合或 LB-EPS 和肉汤-EPS 或 B-EPS）的 EPS 干重、絮凝活性和脱水性能。LB-EPS（2.45g/L）和 TB-EPS（0.99g/L）的最高浓度在发酵 48 小时时达到。TB-EPS（76.4%，14.5s 和 76.5%，15.5s）、LB-EPS（67.8%，8.1s 和 64.7%，7.6s）和肉汤-EPS（61%，6.1s 和 70.4%，6.8s）的最大絮凝活性和脱水性能在 36 和 48 小时的生长时达到。TB-EPS 的絮凝活性和脱水性能高于其他两种 EPS。TB-EPS 和 LB-EPS 的特性是根据其蛋白质和碳水化合物含量来确定的。TB-EPS 中的蛋白质含量要高得多，而 TB-EPS 中的碳水化合物含量仅略高于 LB-EPS。在扫描电子显微镜下观察了斯氏菌在污泥和 TSB 中发酵后的形态，发现细胞尺寸在污泥介质中比 TSB 介质中更大。
