耐高温亚硝酸盐降解菌的分离、鉴定及降低雪茄烟叶亚硝胺的应用  

Heat-tolerant nitrite-degrading bacterial strains:isolation,identification,and applications in reducing nitrosamines in cigar tobacco leaves

作　　者：王光路 卢玉松 刘兰茜 贾玉红 李鹏[3] 胡希 杨雪鹏 WANG Guanglu;LU Yusong;LIU Lanxi;JIA Yuhong;LI Peng;HU Xi;YANG Xuepeng(College of Food and Bioengineering,Zhengzhou University of Light Industry,Zhengzhou 450001,Henan,China;The Great Wall Cigar Factory,China Tobacco Sichuan Industrial Limited Company,Shifang 618000,Sichuan,China;Zhengzhou Tobacco Research Institute of China National Tobacco Corporation,Zhengzhou 450001,Henan,China)

机构地区：[1]郑州轻工业大学食品与生物工程学院,河南郑州450001 [2]四川中烟工业有限责任公司长城雪茄厂,四川什邡618000 [3]中国烟草总公司郑州烟草研究院,河南郑州450001

出　　处：《微生物学通报》2023年第9期3970-3982,共13页Microbiology China

基　　金：国家烟草总公司重点研发项目(110202102020,110202202006)。

摘　　要：【背景】烟草特有亚硝胺(tobacco-specific nitrosamines,TSNAs)是烟草于调制和发酵阶段产生的一类致癌物质,由烟草生物碱与氮氧化物发生亚硝化反应生成,生物碱和亚硝酸盐是TSNAs的直接前体物质。【目的】发掘适用雪茄高温发酵且显著降低TSNAs形成与积累的微生物。【方法】以TSNAs前体物质亚硝酸盐的高效降解为目标,对从雪茄烟叶分离得到的烟草源微生物菌株进行高温培养、亚硝酸盐降解及亚硝酸盐耐受能力研究,得到可于50℃高效降解亚硝酸盐及耐受高浓度亚硝酸盐的微生物菌株,将菌株应用于雪茄烟叶高温发酵35 d,对发酵前后亚硝酸盐、TSNAs、常规化学成分和中性香味成分含量进行测定,分析菌株在雪茄烟叶发酵中对TSNAs含量及烟叶品质的影响。【结果】获得了3株于50℃高效降解亚硝酸盐的菌株NY7、NY8和NY9,分别鉴定为莫海威芽孢杆菌(Bacillus mojavensis)NY7、耐盐芽孢杆菌(Bacillus halotolerans)NY8和枯草芽孢杆菌(Bacillus subtilis)NY9,其中B.halotolerans NY8亚硝酸盐降解能力最为显著。添加了菌株NY8的雪茄烟叶发酵过程中亚硝酸盐和TSNAs含量均显著降低,亚硝酸盐含量减少96.86%,TSNAs总量减少67.14%,烟碱的下降幅度明显高于空白组。中性香味成分总量(除新植二烯外)略有升高。【结论】该菌株适用于雪茄烟叶高温发酵,并高效降解亚硝酸盐,有效减少TSNAs的形成和积累,对雪茄烟叶减害具有重要的科学价值和应用潜力。[Background]Tobacco-specific nitrosamines(TSNAs)are produced by the nitrosation of tobacco alkaloids with nitrogen oxides during the processing of tobacco,especially during the modulation and fermentation stages.[Objective]To mine the microorganisms that can tolerate high-temperature fermentation of cigar tobacco leaves and reduce the accumulation of TSNAs.[Methods]We examined the high-temperature tolerance,nitrite degradation,and nitrite tolerance of the bacterial strains derived from cigar tobacco leaves that could efficiently degrade nitrite and tolerate high concentrations of nitrite at 50°C.A efficient strain was then selected and used for a 35-day high-temperature fermentation of cigar tobacco leaves.We determined the levels of nitrite,TSNAs,conventional chemical components,and neutral aromatic components before and after fermentation to analyze the effects of the strain on TSNAs and tobacco quality during the fermentation process.[Results]Three bacterial strains capable of degrading nitrite at 50℃were isolated and identified,which were Bacillus mojavensis NY7,B.halotolerans NY8,and B.subtilis NY9.Among them,B.halotolerans NY8 exhibited the strongest nitrite-degrading capacity.The high-temperature fermentation of cigar tobacco leaves with NY8 reduced nitrite by 96.86%and TSNAs by 67.14%.Moreover,the nicotine reduction caused by the inoculation of NY8 was significantly higher than that of the control group,and the total neutral aromatic components(except neophytadiene)were slightly increased.[Conclusion]The isolated strains are suitable for high-temperature fermentation of cigar tobacco leaves and demonstrate high efficiency in degrading nitrite and reducing the accumulation of TSNAs.The findings provide inspiration for reducing the harm of cigar tobacco leaves.

关 键 词：雪茄烟叶 菌株筛选 高温发酵 亚硝酸盐降解 烟草特有亚硝胺 

分 类 号：TS453[农业科学—烟草工业]