The effects of temperature, initial pH, salinity of culture medium, and carbon and nitrogen sources on growth and doco- sahexaenoic acid (C22 : 6 n-3, DHA) production from Schizochytrium limacinum OUC88 were investiga...The effects of temperature, initial pH, salinity of culture medium, and carbon and nitrogen sources on growth and doco- sahexaenoic acid (C22 : 6 n-3, DHA) production from Schizochytrium limacinum OUC88 were investigated in the present study. The results revealed that the optimal temperature, initial pH and salinity level of the medium for DHA production were 23℃, 7.0 and 18, respectively. Glucose was proved the best carbon source for the growth and DHA production from S. limacinum. Among the nitrogen sources tested, soybean cake hydrolysate, a cheap by-product, was found to be effective for the accumulation of DHA in S. lima- cinum cells. In addition, increasing the concentration of carbon sources in the medium caused a significant increase in cell biomass; however, accumulation of DHA in cells was mainly stimulated by the ratio of C/N in the medium. Under the optimal culture condi- tions, the maximum DHA yield achieved in flasks was 4.08 g L-1 after 5 d of cultivation.展开更多
目的从裂壶藻(Schizochytrium limacinum)中提取分离多糖并对其进行结构特性分析。方法采用热水提取并结合Q-Sepharose Fast Flow强阴离子交换柱分离,从中获得2种多糖组分(SLW1和SLW2)。运用高效液相色谱法(HPLC)、高效凝胶渗透色谱法(H...目的从裂壶藻(Schizochytrium limacinum)中提取分离多糖并对其进行结构特性分析。方法采用热水提取并结合Q-Sepharose Fast Flow强阴离子交换柱分离,从中获得2种多糖组分(SLW1和SLW2)。运用高效液相色谱法(HPLC)、高效凝胶渗透色谱法(HPGPC)、傅里叶变换红外光谱(FTIR)、甲基化和核磁共振碳谱(13 C-NMR)法分别对其单糖组成、相对分子质量及结构特性进行了分析。结果 2种多糖均以Gal为主(>75%),且含有少量的Glc、Man和GlcN;相对分子质量分别为39.8kD和103.8kD;FTIR显示它们均属于硫酸多糖,其硫酸酯基主要位于半乳糖残基的C6位。结论结构分析表明:SLW2中含有→6)Galf(1→、→5)Galf(1→、→3,4)Galp(1→、→3)Galp(1→以及→4,6)Galp(1→等多种连接方式。展开更多
采用水酶法对裂殖壶菌油脂的提取工艺进行研究,通过单因素和正交实验优化提取工艺条件,并对裂殖壶菌油脂的脂肪酸组成进行分析。实验结果表明,水酶法提取裂殖壶菌油脂的最佳工艺条件:复合酶配比2∶8(纤维素酶∶中性蛋白酶,U∶U),液料比4...采用水酶法对裂殖壶菌油脂的提取工艺进行研究,通过单因素和正交实验优化提取工艺条件,并对裂殖壶菌油脂的脂肪酸组成进行分析。实验结果表明,水酶法提取裂殖壶菌油脂的最佳工艺条件:复合酶配比2∶8(纤维素酶∶中性蛋白酶,U∶U),液料比4 m L/g,加酶量2 500 U/g,酶解温度55℃,酶解时间4h;在此优化条件下,裂殖壶菌油脂提取率为82.47%。裂殖壶菌油脂脂肪酸以C14∶0、C16∶0、C22∶5n-6和C22∶6n-3为主,其脂肪酸组成简单,且C22∶6n-3质量分数高达32.65%,表明裂殖壶菌油脂具有很高的营养价值和功能性油脂的开发潜力,可作为C22∶6n-3的重要食药来源。展开更多
文摘The effects of temperature, initial pH, salinity of culture medium, and carbon and nitrogen sources on growth and doco- sahexaenoic acid (C22 : 6 n-3, DHA) production from Schizochytrium limacinum OUC88 were investigated in the present study. The results revealed that the optimal temperature, initial pH and salinity level of the medium for DHA production were 23℃, 7.0 and 18, respectively. Glucose was proved the best carbon source for the growth and DHA production from S. limacinum. Among the nitrogen sources tested, soybean cake hydrolysate, a cheap by-product, was found to be effective for the accumulation of DHA in S. lima- cinum cells. In addition, increasing the concentration of carbon sources in the medium caused a significant increase in cell biomass; however, accumulation of DHA in cells was mainly stimulated by the ratio of C/N in the medium. Under the optimal culture condi- tions, the maximum DHA yield achieved in flasks was 4.08 g L-1 after 5 d of cultivation.
文摘采用水酶法对裂殖壶菌油脂的提取工艺进行研究,通过单因素和正交实验优化提取工艺条件,并对裂殖壶菌油脂的脂肪酸组成进行分析。实验结果表明,水酶法提取裂殖壶菌油脂的最佳工艺条件:复合酶配比2∶8(纤维素酶∶中性蛋白酶,U∶U),液料比4 m L/g,加酶量2 500 U/g,酶解温度55℃,酶解时间4h;在此优化条件下,裂殖壶菌油脂提取率为82.47%。裂殖壶菌油脂脂肪酸以C14∶0、C16∶0、C22∶5n-6和C22∶6n-3为主,其脂肪酸组成简单,且C22∶6n-3质量分数高达32.65%,表明裂殖壶菌油脂具有很高的营养价值和功能性油脂的开发潜力,可作为C22∶6n-3的重要食药来源。
