| 摘要: |
| 对一株分泌热稳定κ-卡拉胶酶印尼热泉菌进行了种属鉴定, 并采用响应面法对该菌发酵产酶条件进行了优化。鉴定结果表明, 该菌株属于芽孢杆菌属(Bacillus), 命名为Bacillus sp. Car19(GeneBank: KT865196)。发酵条件优化结果显示, 9个环境因子影响Bacillus sp. Car19产酶量。其中影响Bacillus sp. Car19产酶量的三个主要因素分别为培养温度、培养基中Cu2+浓度和培养基中NaCl浓度。综合次要因素对Bacillus sp. Car19产酶影响, Bacillus sp. Car19最佳产酶发酵条件为: 培养温度52.31℃、Cu2+浓度6.93 mmol/L、NaCl浓度37.03 g/L, 培养基pH为6, 接种量1%, 培养时间36h, 半乳糖浓度0.3 g/L,硝酸铵浓度7g/L, 卡拉胶浓度0.5g/L。优化后发酵上清液酶活力达到15.21 U/mL, 与优化前相比提高了1.5 倍。 |
| 关键词: 热泉菌 卡拉胶酶 优化 响应面 |
| DOI：10.11759/hykx20160125001 |
| 分类号: |
| 基金项目:海洋公益性行业科研专项项目(201505026); 青岛市应用基础研究计划项目(14-2-4-14-jch); 国家海洋局海洋生物活性物质与现代分析技术重点实验室开放基金(MBSMAT-2015-06) |
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| Optimization of fermentation conditions for thermostable κ-carrageenase production of strain Bacillus sp. Car19 |
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XIE Mai-sheng,LI Jiang,LIN Xue-zheng,HE Pei-qing
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| Abstract: |
| In this study, we identified a high-yield κ-carrageenase bacteria strain by its 16S rDNA sequence and optimized the fermentation conditions using a response surface methodology. The results show that the hot-spring bacterium was 99% identical to Bacillus sp. and therefore we assigned it to the Bacillus genus and named it Bacillus sp. Car19 (GenBank accession number: KT865196). The optimized fermentation conditions of Bacillus sp. Car19 involve nine factors that affect Bacillus sp. Car19 carrageenase production, and the three main factors are culture temperature, Cu2+ concentration, and NaCl concentration. Combined with subordinate factors, the final optimized fermentation conditions for maximal activity, as determined by regression analysis are as follows: a culture temperature of 52.31℃, a Cu2+ concentration of 6.93 mmol/L, an NaCl concentration of 37.03 g/L, medium pH = 6, 1% inoculation quantity, 36 h incubation time, a galactose concentration of 0.3 g/L, an ammonium nitrate concentration of 7 g/L, and a carrageenan concentration of 0.5 g/L. The supernatant carrageenase activity after optimized fermentation can reach 15.82 U/mL, which is 1.5 times that without optimization. |
| Key words: Hot spring bacterium Carrageenase Optimization Response surface |
