Abstract: Nicotine is the main component of tobacco alkaloids, its content will directly affect the quality of tobacco leaves. At present, our countrys cigarette enterprises face a hard problem that upper leaves of high nicotine content cant be greatly used in tobacco blend. Besides, since nicotine is toxic, how to remove nicotine from tobacco waste is another major challenge which tobacco industry faces, so its very important to find a simple, low consumption, environmental approach to degrade nicotine. Our laboratory previously isolated and stored a nicotine degrading strain AH14 and this study identified AH14 as Arthrobacter sp., according to the morphological characteristics, biochemical and physiological property, 16S rDNA sequencing and phylogenetic tree analysis. Then, with 6 g/L nicotine as the sole carbon source, the nicotine degradation conditions of this strain was optimized, the results showed that the optimum conditions for nicotine degradation were: inoculum size 12.5%, pH 6.5, 34℃, rotation rate 120 r/min. Under the best condition, the strain could completely degrade 6 g/L nicotine and degrade 30.22% of 14 g/L nicotine after cultication for 120 h. It showed that the strain AH14 had a strong ability to degrade nicotine, so it could be applied to degrade high concentration nicotine.

Key words: Arthrobacter sp., nicotine degradation, conditions optimization, high-endurance

摘要： 烟碱是烟草生物碱的主要成分，其含量高低直接影响着烟叶的品质，目前我国的卷烟企业面临着因上部烟叶烟碱含量高而难以较多地用于叶组配方的难题。此外，因烟碱具有毒性，如何将其从烟草废弃物中除掉是烟草行业面临的又一大难题，因此寻找一种简单、低耗、环保的方法来降解烟碱十分重要。前期分离保存了一株能够降解烟碱的细菌AH14，从形态结构特征、生理生化特性、16S rDNA序列分析以及构建系统进化树等方面对其进行鉴定，结果表明AH14为节杆菌（Arthrobacter sp）。以6 g/L的烟碱为唯一碳源，对该菌株降烟碱的条件进行了优化研究，得到其降解烟碱的最适条件为：接种量12.5%、pH 6.5、温度34℃、转速120 r/min。在此条件下，该菌能够在120 h内将6 g/L的烟碱完全降解，14 g/L的烟碱降解率为30.22%。说明菌株AH14具有极强的降解烟碱能力，可应用于降解高浓度烟碱。

关键词: 节杆菌, 烟碱降解, 条件优化, 耐受力高