Yu Jicheng, Liu Qiu, Liu Qiao, Liu Xiangdong, Sun Qiang, Yan Jianfang, Qi Xiaohui, Fan Shengdi
Department of Bioengineering, Dalian Nationalities University, Dalian, PR China.
Bioresour Technol. 2008 Apr;99(6):2087-91. doi: 10.1016/j.biortech.2007.03.023. Epub 2007 May 1.
Streptomyces rimosus MY02 was isolated from a soil sample which was collected from the northeast of China. The effect of medium components (i.e. carbon and nitrogen sources) and other culture requirements (i.e. initial pH and temperature) on production of antifungal antibiotics by S. rimosus MY02 was investigated in our work. The best conditions for the strain MY02 in 250-ml Erlenmeyer flask, for example, initial pH, temperature, medium capacity, agitation rate, seed age, inoculum size and growth period, were 6.0, 28 degrees C, 50 ml, 180 rpm, 4 days, 10% (v/v) and 120 h, respectively. Components and dosage of the medium, which effect antibiotic production, were determined by uniform design combined with regression analysis; meanwhile, a regression model was established. The components and dosage of the best medium were starch, 53.313 g; defatted peanut powder, 9.376 g; (NH(4))(2)SO(4), 6.244 g; and NaCl, 5.836 g; in 1l of distilled water. Residual values obtained between the observed values by experiments and predicted values by the model are very low, and this result showed that the experimental results were well in consistence with the calculation results via the model. The antifungal antibiotic production by S. rimosus MY02 was improved by optimization of the components and culture requirements. The diameter of inhibition zone of the culture supernatant from S. rimosus MY02 against Fusarium oxysporium f sp. cucumarinum was 33.19 mm.
龟裂链霉菌MY02是从中国东北地区采集的土壤样本中分离得到的。在我们的研究中，考察了培养基成分（即碳源和氮源）以及其他培养条件（即初始pH值和温度）对龟裂链霉菌MY02产生抗真菌抗生素的影响。例如，在250毫升锥形瓶中，菌株MY02的最佳条件分别为初始pH值6.0、温度28℃、培养基体积50毫升、搅拌速度180转/分钟、种子培养时间4天、接种量10%（v/v）和生长周期120小时。采用均匀设计结合回归分析确定了影响抗生素产生的培养基成分和用量；同时建立了回归模型。最佳培养基的成分和用量为1升蒸馏水中含淀粉53.313克、脱脂花生粉9.376克、硫酸铵6.244克和氯化钠5.836克。实验观测值与模型预测值之间的残差值非常低，这表明实验结果与通过模型的计算结果高度一致。通过优化成分和培养条件提高了龟裂链霉菌MY02的抗真菌抗生素产量。龟裂链霉菌MY02培养上清液对尖孢镰刀菌黄瓜专化型的抑菌圈直径为33.19毫米。
