含硫无机物对克雷伯氏菌NIII2产絮凝剂特性的影响  

Effects of sulfur-containing inorganic compounds on production of bioflocculant by Klebsiella sp. NIII2

作　　者：赵璇[1] 聂麦茜[1] 聂红云[1] 白雪蕊[1] 郭育涛[1] 王丹[1] 王陇梅 

机构地区：[1]西安建筑科技大学环境与市政工程学院,西安710055

出　　处：《环境工程学报》2016年第7期3905-3911,共7页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(51278405);陕西省重点科技创新团队建设计划(2013KCT-13);陕西省国际科技合作重点项目(2012KW-25)

摘　　要：研究了含硫无机物对克雷伯氏菌NIII2发酵产絮凝剂特性的影响作用。结果表明:未外加硫或投加足量硫化钠时,NIII2菌,因易产酸,絮凝剂产量低,约2.14 g·L^(-1);而投加足够(16 mg·L^(-1),以硫元素计)硫代硫酸钠和硫酸钠时,絮凝剂产量提高,最高可达9.03 g·L^(-1)。与未外加硫相比,外加足够硫酸钠或硫代硫酸钠,能使絮凝剂中蛋白质相对含量分别提高29.8%和25%,并提高絮凝剂中总巯基、二硫键含量以及Zeta电位,致使絮凝剂粒径可广泛分布于0.5~3.3μm范围内,且大粒径分子所占比例提高,聚合度增大,从而稳定絮凝剂活性和性能。投加8.0 mg·L^(-1)絮凝剂,2 g·L^(-1)高岭土所产生的SS去除率达93%左右。NIII2菌所产絮凝剂为糖蛋白类,未投加含硫无机物或投加硫化钠时所产絮凝剂为O-糖苷键相连的糖蛋白,而投加硫代硫酸钠、硫酸钠时所产絮凝剂则为絮凝剂为非O-糖苷键糖蛋白。The effects of sulfur-containing compounds in medium on bioflocculant secretion by Klebsiella sp. NIII2 were studied. Using sucrose as a carbon source and an appropriate amount Na_2S as a sulfur source or no sulfur-containing inorganic compounds in the fermentation medium,acidic compounds,which often decrease the pH values of the culture broth,were easily produced by strain NIII2. This led to a dramatic decline in bioflocculant yields（ to less than 2. 14 g·L^（-1））. The yield was greatly improved by the addition of Na_2SO_4 or Na_2S_2O_3（ 16mg·L^（-1）,as elemental S） as a sulfur source. The highest observed yield was 9. 03 g·L^（-1）. After adding an appropriate amount of Na_2SO_4 or Na_2S_2O_3to the medium,the relative protein contents in the bioflocculant improved by 29. 8% and 25%,respectively,compared to that without supplemental sulfur-containing inorganic compounds.The amounts of total thiol functional groups and disulfide bonds in the bioflocculant and its zeta potential also increased. Additionally,although the particle size of the bioflocculant was distributed in the range of 0. 5 to 3. 3μm,the number of large-sized particles increased. This high degree of polymerization of the bioflocculant guaranteed stable,high flocculation activity. With 8. 0 mg·L^（-1）bioflocculant,the removal rate of the suspended solid in kaolin solution（ 2 g · L^（-1）） was up to 93%. The active bioflocculant was a glycoprotein with non-O-glycosidic bonds between proteins and saccharides.

关 键 词：含硫无机物 克雷伯氏菌NIII2 微生物絮凝剂 糖蛋白 

分 类 号：X703.5[环境科学与工程—环境工程]