Two hundred strains of bacteria from Antarctic sea ice were collected and screened for their ability of producing eieosapentaenoic acid （EPA, 20： 5ω3） by means of Gas Chromatography/Mass Spetmmetry （GC/MS）. Eigh...Two hundred strains of bacteria from Antarctic sea ice were collected and screened for their ability of producing eieosapentaenoic acid （EPA, 20： 5ω3） by means of Gas Chromatography/Mass Spetmmetry （GC/MS）. Eight strains of bacteria containing EPA were investigated, among which the outstanding one was recorded as NJ136. This bacterium was identified as Shewanella by the biochemical characteristics and 16S rRNA sequence. Response surface methodology （RSM） was applied to optimize the medium ingredients. A 24 full factorial central composite design （FFCCD） was employed to determine the naximum EPA production at optimum levels of pH, NaC1, glucose and yeast extract. The predicted optimal combination of media constituents for maximum 14.02 mg/g （ about 1.7-fold increase） EPA production were determined as 30.15%e （m/v） NaC1, 9.98 g/L glucose, 4.42 g/L yeast extract and pH 6.08. The actual experimental results were in agreement with the prediction.展开更多
基金Supported by the National Natural Science Foundation of China （No. 40206022 ＆ No. 40506005）.
文摘Two hundred strains of bacteria from Antarctic sea ice were collected and screened for their ability of producing eieosapentaenoic acid （EPA, 20： 5ω3） by means of Gas Chromatography/Mass Spetmmetry （GC/MS）. Eight strains of bacteria containing EPA were investigated, among which the outstanding one was recorded as NJ136. This bacterium was identified as Shewanella by the biochemical characteristics and 16S rRNA sequence. Response surface methodology （RSM） was applied to optimize the medium ingredients. A 24 full factorial central composite design （FFCCD） was employed to determine the naximum EPA production at optimum levels of pH, NaC1, glucose and yeast extract. The predicted optimal combination of media constituents for maximum 14.02 mg/g （ about 1.7-fold increase） EPA production were determined as 30.15%e （m/v） NaC1, 9.98 g/L glucose, 4.42 g/L yeast extract and pH 6.08. The actual experimental results were in agreement with the prediction.
