发酵液中多拉菌素的提取和萃取条件研究

采用单因素实验,分别研究提取试剂、发酵液放置时间、pH值和温度对发酵液中多拉菌素提取效果的影响;然后以乙酸乙酯为萃取试剂,研究萃取次数及萃取体积对多拉菌素萃取效果的影响。结果显示,甲醇为最佳提取试剂;发酵液在pH为3～11、温度为20～80℃的条件下放置144 h,多拉菌素均能稳定存在,提取得到的多拉菌素的质量浓度没有显著变化;浓缩提取液液经2倍体积乙酸乙酯萃取2次即可。该条件下多拉菌素的质量浓度和萃取率分别为151.78μg/mL和98.00%。

Extraction Conditions of Doramectin in Fermentation Broth of Streptomyces avermitilis

The optimal extraction conditions of doramectin in fermentation broth of Streptomyces avermitilis were investigated by parallel experiments.Factors including distribution ratio of doramectin in fermentation broth(hyphae or supernatant),extractants,extraction times,storage time,pH and temperature on extraction results were investigated with one-factor experiments.Meanwhile,the optimal extraction times and extracting volume were optimized based on using ethyl acetate.The optimal extraction conditions of doramectin in fermentation broth of Streptomyces avermitilis were obtained as follows:the optimal extraction solvent was methanol,and doramectin in fermentation broth could be stored for at least 144 h within the conditions of pH from 3 to 11 and temperature from 20 to 80 ℃.Using ethyl acetate to extract doramectin,twice was the optimal extracting time,and the twice volume of ethyl acetate and concentrated extract was the best extraction proportion.Under the optimal extraction conditions,the concentration of doramectin and its extraction rate were 151.78 μg/mL and 98.00%,respectively.