| 摘要: |
| 以褐藻酸钠为唯一碳源, 从腐烂海带中筛选得到褐藻酸钠降解能力较强的菌株H4, 经生理生化和16S rDNA 序列分析鉴定该菌株属于交替单胞菌属(Alteromonas)。对菌株H4 的发酵条件优化研究表明, H4 的较优培养基组成为(w/v): 褐藻酸钠0.6%、酵母粉0.5%、蛋白胨0.25%、NaCl 3%; 较优培养条件为: 培养温度28℃, 初始pH7.5, 接种量1.5%(v/v), 培养时间48 h。Fe3+对交替单胞菌H4 的产酶有明显的促进作用, 这在其他褐藻酸裂解酶生产菌株中未见报道, 而Cu2+对褐藻酸裂解酶的抑制作用高达45.78%。在优化后的培养条件下, 粗酶液酶活达到146.45 U/mL, 较优化前提高了39.4%。 |
| 关键词: 褐藻酸钠降解菌 筛选 鉴定 酶活优化 |
| DOI：10.11759/hykx20130722001 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(41176144); 海洋公益性行业科研经费资助专项(20120527); 山东省自然科学基金项目(JQ200914) |
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| The screening, identification of alginate degrading bacteria and optimization of fermentation conditions |
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| Abstract: |
| A screening work was carried out to obtain a bacterium with high alginate lyase activity by using alginate as sole source of carbon. The strain was identified as Alteromonas based on physiology and biochemistry analysis, 16S rDNA sequence analysis, and was named Alteromonas sp. H4. It was shown that the optimal culture medium composition of producing alginate lyase was as follows (w/v): alginate 0.6%, yeast extracts 0.5%, peptone 0.25% and NaCl 3%. The optimized culture condition was as follows: culture temperature 28℃, initial pH value 7.5, inoculum size 1.5%(v/v) and optimal harvest time 48 h. The activity of alginate lyase was activated by Fe3+, which hasn’t been reported in other alginate lyase production strains, and the inhibitory effect by Cu2+ was up to 45.78%. Under optimized conditions, the alginate lyase activity of the Alteromonas sp. H4 was146.45 U/ml, which was increased by 39.4% than that before optimization. |
| Key words: alginate degrading bacteria screening identification optimization |
