解淀粉芽胞杆菌FJAT-8754产纤维素酶和淀粉酶特性及发酵条件优化  

The Characteristics of Cellulase and Amylase fromB.amyloliquefaciens FAJT-8754 and Optimization of Fermentation Conditions

作　　者：王凯[1,2] 蓝江林[2] 刘波[2] 刘程程[3] 李安琪[1,2] 

机构地区：[1]福州大学生物科学与工程学院,福建福州350002 [2]福建省农业科学院农业生物资源研究所,福建福州350003 [3]福建农林大学生命科学学院,福建福州350003

出　　处：《福建农业学报》2014年第4期357-363,共7页Fujian Journal of Agricultural Sciences

基　　金：农业部公益性行业科研专项(201303094);国家国际合作项目(2012DFA31120);国家科技支撑计划项目(2012BAD14B15);国家自然科学基金(31370059)

摘　　要：采用淀粉平板和羧甲基纤维素钠(CMC-Na)平板从选取的140株芽胞杆菌中初筛出8株具有产纤维素酶和淀粉酶复合酶芽胞杆菌,经酶活力测定解淀粉芽胞杆菌FJAT-8754(Bacillus amyloliquefaciens)具有较高的淀粉酶、纤维素酶活力。通过研究解淀粉芽胞杆菌FJAT-8754的生长、产酶曲线以及酶学特性,确定在发酵28h后菌体生长进入稳定期,培养44h时发酵液中活菌数达到最大为4.41×109 cfu·mL-1,在36h时纤维素酶、淀粉酶均达到酶活最高峰,酶活分别为135.8、1 543.3U·mL-1;纤维素酶反应最适pH值为5.5、最适温度为50℃,Vmax为5.14×10-3 mg·mL-1·min-1、Km值为7.71×10-1 mg·mL-1;淀粉酶反应最适pH值为5.5、最适温度为55℃,Vmax为3.35×10-2 mg·mL-1·min-1、Km值为6.03×10-3 mg·mL-1。采用3因素7水平,即U7(73)均匀设计法优化解淀粉芽胞杆菌产酶条件,确定产纤维素酶、淀粉酶的最优条件均为:初始pH值6.2、培养温度37.5℃、转速180r·min-1,优化后解淀粉芽胞杆菌FJAT-8754纤维素酶活力为202.9U·mL-1、淀粉酶活力为2 392.9U·mL-1。Eight Bacillus strains which produce cellulase and amylase were screened from 140 standard Bacillus strains by using starch medium and carboxymethylcellulose sodium （CMC-Na） plate screening method .FJAT-8754 had the highest cellulase and amylase producing activities and the biological characterizes （e .g .growth curves , dynamic changes of enzyme activity and enzymatic properties ） were tested .Our results suggested that the stationary phase of FJAT-8754 was at 28 h ,the colony count was 4.41 × 109 cfu · mL -1 at 44 h and the activity of cellulase and amylase peaked at 36 h simultaneously .Meanwhile ,the optimum reaction conditions for cellulase were at pH 5.5 ,55℃ ,Vmax was 5.14 × 10-3 mg · mL -1 · min-1 and Km was 7.71 × 10-1 mg · mL -1 ;the optimal reaction conditions of amylase were at pH 5.5 ,60℃ ,Vmax was 3.35 × 10-2 mg · mL -1 · min-1 and Km was 6.03 × 10-3 mg · mL -1 .Furthermore ,uniform design assays showed that the optimal submerged culture conditions for cellulase＆amp;nbsp;and amylase was at pH 6.2 ,fermentation temperature was at 37.5℃ ,shaking speed was 180 r · min-1 ,and the activity of cellulase and amylase could reach 202.9 , 2 392.9 U · mL -1 , respectively .

关 键 词：纤维素酶 淀粉酶 芽胞杆菌 发酵 均匀设计法 

分 类 号：Q939[生物学—微生物学]