光合细菌Ⅰ的分离及其培养条件的优化

Isolation and Optimization of Culture Medium for Photosynthetic Bacterium-I

从虾塘淤泥中分离出1株能降解亚硝酸盐的光合细菌I,初步鉴定其为球形红假单胞菌。利用Plackett-Barman设计法,对影响光合细菌I生长量的11个因素进行了筛选,确定影响该菌生长的培养基的主要因素为NH_4Cl、NaHCO_3、温度和接种量;采用响应面法对其中的4个显著因子的最佳水平进行研究,结果表明,当NH_4Cl为0.99 g/L、NaHCO_3为1.68 g/L、温度30.18℃、接种量8.90%时,经过5 d培养,菌体密度显著提高,培养液OD_(660)可以从0.972提高至1.343。

Photosynthetic bacterium （PSB-I） which can degrade nitrite was isolated from mud in shrimp ponds and was identified as Rhodopseudomonas spheroids primarily. Also, the optimal culture condition of PSB-I was studied. The influences of I 1 factors of the media were evaluated using a Plackett-Burman design. The results showed that NH4 C1, NaHCO3, temperature and inoculum were significant factors. Then response surface method was used to optimize the four main factors. In the experiment, the optimal culture for the growth of photosynthetic bacteria was determined as NH4 Cl（0.99 g/L）, NaHCO3 （1. 68 g/L）, at 30.18 ℃, with inoculurn of 8.90%. Under the condition, the concentration of photosynthetic bacteria was augmented significantly and the OD66o of the broth increased from 0. 972 to I. 343 after the 5 d culture.