交替假单胞菌BYS-2产褐藻胶裂解酶条件研究
Optimization of alginate lyase-producing conditions by Pseudoalteromonas sp. BYS-2

以褐藻酸钠作为褐藻胶裂解酶产生菌初筛培养基唯一碳源，从鲍鱼养殖水样中分离获得一株产褐藻胶裂解酶的微生物，形态学和分子生物学16S rDNA鉴定结果显示，该菌株为交替假单胞菌Pseudoalteromonas sp.BYS-2. 对该菌株进行产酶条件研究，获得最适产酶配方为：褐藻酸钠1 g·L-1，葡萄糖0.5 g·L-1，酵母膏10 g·L-1，黄豆饼粉3 g·L-1，(NH4)2HPO4 3 g·L-1，初始培养基pH8.0；最佳产酶条件为：接种量2%（体积分数），装液量50 mL/250 mL，发酵温度20 ℃，摇床转速200 r·min-1，在此条件下发酵24 h酶活力可达5.29 U·mL-1，比优化前（1.57 U·mL-1）提高2.37倍.
With sodium alginate as the only carbon source of primary screening medium，one of the microorganisms that producing alginate lyase had been isolated from abalone aquaculture water，which was identified as Pseudoalteromonas sp.BYS-2 via morphological characteristics and 16S rDNA sequence analysis. Based on the results of fermentation experiments，the optimal liquid medium consisted of those compounds as follow：sodium alginate 1 g·L-1，glucose 0.5 g·L-1，yeast extract 10 g·L-1, soybean cake powder 3 g·L-1，(NH4)2HPO4 3 g·L-1，pH 8.0. The optimal fermentation conditions included：inoculation 2%(volume fraction) ，medium volume 50 mL /250 mL，incubate temperature 20 ℃ and shaking speed 200 r·min-1. Fermenting about 24 h under these conditions，alginate lyase activity could reach 5.29 U·mL-1 which was 2.37 times higher than before optimization (1.57 U·mL-1)