The culture conditions of polar psychrotrophic bacterium Pseudoalteromonas sp. QI-1 were optimized for the production of cold-active protease. The optimum fermentation conditions were determined as follows: optimal temperatures for growth and enzyme production were both at 5 ℃, inoculation volume was 1％ ,and liquid volume was 10％ at pH 5. Culture medium for protease production of strain QI-1 was also studied. Results showed that nitrogen source and carbon source preferred by protease production were bran and sodium acetate. 2％ NaC1,10 mmol/L Mg2+ ,0.5％ Tween-80 and 0.75％ casein were suitable for the enzyme production. The orthogonal experiment design showed that the optimum medium (per liter) consisted of 5 g bran,2.5 g yeast extract,3 g casein,3 g MgCl2 ·6H20 and 1.5 g KCl. Under the optimum condition, the protease activity was up to 166. 20 U/mL and the yield of protease increased about 56％.%对极地适冷菌Pseudoalteromonas sp.QI-1产适冷蛋白酶的发酵条件进行优化.结果表明:菌株QI-1的最适生长和产酶温度均为5℃;最佳接种量为1%;发酵培养基的最适初始pH和最佳装样量分别为5和10%;盐度为2%时对菌株的生长和产酶最为有利;麸皮和醋酸钠分别为最佳N源和C源;添加0.75%酪蛋白时菌株QI-1胞外蛋白酶的活性最高;10 mmol/L Mg2+和0.5%Tween-80有利于产酶.正交试验结果表明:菌株Pseudoalteromonas sp.QI-1产蛋白酶较佳培养基配方(g/L)为麸皮5,酵母粉2.5,酪蛋白3,MgCl2·6H2O3,KCl 1.5;发酵液比酶活为166.20 U/mL,较优化前提高了约56%.
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机译：南极适冷菌Rheinheimera sp.97产抗菌活性物质发酵条件的优化Optimization of Fermentation Medium and Conditions of Antibiotic Active Substances Produced by Antarctic Psychrotrophic Bacterium Rheinheimera sp.97
