产木聚糖酶芽胞杆菌的筛选及产酶条件优化  

Screening of Xylanase-producing Bacillus sp. and Optimization of Fermentation Process

作　　者：刘程程[1,2] 刘波[1,2] 蓝江林[2] 王凯[3] 

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

出　　处：《福建农业学报》2014年第8期757-767,共11页Fujian Journal of Agricultural Sciences

基　　金：国家公益性行业科研专项(201303094);科技部国际合作科技专项(2012DFA31120);国家科技支撑计划项目(2012BAD14B15);国家自然科学基金项目(31370059)

摘　　要：利用木聚糖酶选择培养基,从120株标准芽胞杆菌中筛选出37株能够形成明显透明圈的芽胞杆菌。经产酶发酵液培养基复筛,得到1株木聚糖酶活性较高的菌株FJAT-14260(沙福芽胞杆菌Bacillus safensis)。采用单因素实验设计和正交实验设计进行优化,结果表明,在培养基优化中对产酶影响最大的因素是底物浓度;在发酵条件优化中对产酶影响最大的因素是培养温度。优化得到FJAT-14260的最佳产酶发酵条件为:碳源(酵母粉)7g·L-1,氮源(蛋白胨)9g·L-1,底物(木聚糖)浓度10g·L-1,培养温度30℃,初始pH值8,装液量30mL/250mL。在此条件下FJAT-14260在发酵32h时酶活力达到113 585.78U·mL-1,比优化前提高了4.62倍。Selective medium for xylanase was used in screening the xylanase producing Bacillus strains . Thirty-seven of the 120 Bacillus strains tested were found to form transparent circles on the plates . After a secondary screening with the enzyme fermentation medium ,B . safensis FJAT-14260 was determined to be the most desirable strain for the xylanase production . A single factor and an orthogonal experiment were used to optimize the fermentation conditions . The results showed the substrate concentration to be the most important factor relating to the medium ,and temperature ,the most critical condition for the fermentation process . In all ,the best medium for the enzyme production consisted of carbon source （yeast extract） at 7 g · L -1 ,nitrogen source （peptone） at 9 g · L -1 ,and substrate （xylan） at 10 g · L -1 . And ,the optimal fermentation temperature was 30℃ ,initial pH at 8.0 , and liquid volume at 30 mL/250 mL . Under these conditions ,after allowing FJAT-14260 to ferment for 32 h ,the xylanase activity could reach as high as 113 585.78 U · mL -1 ,which was 4.62 times of what was without the optimization .

关 键 词：芽胞杆菌 木聚糖酶 发酵条件 

分 类 号：Q939[生物学—微生物学]