脱硫菌ZD-1生长条件的优化

Optimization of the growth conditions of Corynebacterium sp.ZD-1, a sulfur compounds-degradation bacterium

从炼油厂污泥中分离出一株能专一脱除二苯并噻吩(dibenzothiophene,DBT)中的硫,并生成2 羟基联苯(2 hy droxybiphenyl,2 HBP)的棒杆菌属(Corynebacterium)菌株ZD 1.ZD 1能够利用DBT作为惟一硫源,以甘油作为碳源,用摇瓶培养法测定了该菌株的生长和脱硫曲线.该菌株在培养45h时菌体质量浓度达到最大,在指数生长后期的菌体脱硫活性最高,2 HBP的比生成速率可达0.14(mmol/(kg·min)).同时还考察了影响该菌株生长的初始pH、碳源类型及其质量浓度、硫源类型及其浓度以及氮源质量浓度和生长温度.ZD 1能利用多种碳源和硫源,其中以甘油和DBT为最适宜.结果表明,pH=6.0～7.5,10g/L的甘油,0.2mmol/L的DBT,5g/L的氯化铵,温度为30℃时ZD 1的生长最好.

A strain isolated from refinery sludge and identified as Corynebacterium sp. ZD-1, can metabolize dibenzothiophene (DBT) to 2-hydroxybiphenyl (2-HBP) through a sulfur-specific pathway. The ability of strain ZD-1 to metabolize DBT in the presence of glycerol was investigated. The experimental results showed that the strain had maximal desulfurization activity in the late exponential growth phase; the specific production rate of (2-HBP) was about 0.14 (mmol/(kg·min)), and that the strain reached maximum growth (1.80()g/L) in shaking flask culture after 45.5()h. Some factors such as initial pH, temperature, carbon source, sulfur source, and nitrogen source affecting the growth of corynebacterion sp. ZD-1 were also studied. The optimum culture conditions for ZD-1 were found to be initial pH=6.0～7.5, 10()g/L of glycerol, 5()g/L of NH_4Cl, (0.2()mmol/)L of DBT and 30℃.