Isolation of nicotine-degrading bacterium Pseudomonas sp. Nic22, and its potential application in tobacco processing

Nicotine-degrading bacteria were isolated from tobacco leaves and the tobacco field soil using medium containing nicotine as the sole carbon and nitrogen source. One purified isolate with a higher capacity for nicotine degradation was identified and named Pseudomonas sp. Nic22 based on 16S rDNA sequence and on morphological and biochemical features. The optimal culture condition of strain Pseudomonas sp. Nic22 for nicotine degradation is pH 6.5 and 30–34 °C. This strain can decompose nicotine from different tobacco samples including Burley, Oriental and Zimbabwe LB4. The crude enzyme extract of Pseudomonas sp. Nic22 also decomposed nicotine and significantly improved the quality of tobacco leaf.