Department of Biological Environment, Kangwon National University, Chuncheon, Kangwon-do, South Korea.
J Photochem Photobiol B. 2010 Oct 5;101(1):16-21. doi: 10.1016/j.jphotobiol.2010.06.006. Epub 2010 Jun 30.
A bioluminescent bacterium Photobacterium phosphoreum has been used widely as an indicator of pollutants where the presence of toxic chemicals decreases light output. The optimum conditions for the growth and bioluminescence of P. phosphoreum KCTC 2852 were investigated using modified Boss medium and two environmental conditions (pH and temperature). Optimized conditions that supported growth of P. phosphoreum with high bioluminescence intensities were: NaCl (20 g/L), glycerol (2.5 g/L), peptone (1.0 g/L), and yeast extract (1.0 g/L). Growth and bioluminescence gradually increased as pH increased reaching a maximum at pH 7.0. The maximum temperature for growth and bioluminescence was 20 degrees C. Based on these optimum conditions for bioluminescence, a continuous culture reactor of P. phosphoreum was operated. During the continuous operation, the optimized medium maintained bioluminescence with a high relative light unit (RLU) around 13,600 for more than 120 h. When zinc (0.5 mg/L) was added to the reactor, an EC(50) was observed in 15 min. The detection limit was improved by using the modified Boss medium since the modified Boss medium contained less organic matter which minimizes the complexation and precipitation of heavy metals compared to other enrichment media with high levels of organic matter.
发光细菌 Photobacterium phosphoreum 被广泛用作污染物的指示剂，其中有毒化学物质的存在会降低光输出。本研究使用改良的 Boss 培养基和两种环境条件（pH 和温度）来研究 P. phosphoreum KCTC 2852 的生长和生物发光的最佳条件。支持 P. phosphoreum 高生物发光强度生长的最佳条件为：NaCl（20 g/L）、甘油（2.5 g/L）、蛋白胨（1.0 g/L）和酵母提取物（1.0 g/L）。随着 pH 值的升高，生长和生物发光逐渐增加，在 pH 7.0 时达到最大值。生长和生物发光的最大温度为 20°C。基于这些生物发光的最佳条件，连续培养了 P. phosphoreum。在连续操作过程中，优化后的培养基保持生物发光，相对光单位（RLU）约为 13600，持续 120 小时以上。当向反应器中添加锌（0.5 mg/L）时，在 15 分钟内观察到 EC(50)。与其他含有高浓度有机物的富集培养基相比，改良的 Boss 培养基由于含有较少的有机物，从而最大限度地减少了重金属的络合和沉淀，因此提高了检测限。
