气调醇化过程中片烟细菌群落结构的变化

气调醇化是片烟醇化的一种方法。微生物尤其是细菌在片烟醇化过程中对烟叶的吸食品质起着至关重要的作用。为研究气调醇化过程中片烟细菌群落结构变化规律，利用Illumina MiSeq测序平台比较气调防霉杀虫阶段（S1）、气调醇化阶段（S2）及气调保质阶段（S3）共36份样品的细菌16S rDNA序列的多样性。结果表明，从S1到S3的过程中，片烟中细菌的物种丰富度和多样性水平呈增加趋势。S1阶段片烟的优势种群为鞘氨醇单胞菌属、假单胞菌属和甲基杆菌属，其占比在整个气调醇化过程中呈逐渐下降趋势；S2阶段的优势种群为芽孢杆菌属、鞘氨醇单胞菌属和伯克霍尔德菌属，其中芽孢杆菌属和伯克霍尔德菌属在整个气调醇化过程中占比呈先上升后下降的趋势；S3阶段细菌种群分布较为均匀。非度量多维尺度分析结果表明，3个醇化阶段的样品可以较明显地区分开来。可见，气调醇化过程中片烟的细菌种群组成非常丰富，不同醇化阶段活跃的微生物类群有所不同，鞘氨醇单胞菌属、假单胞菌属和甲基杆菌属主要在醇化前期参与了烟叶醇化过程，而芽孢杆菌属和伯克霍尔德菌属则主要在醇化后期发挥着微生物醇化的作用。

Alteration of Bacterial Community Structures of Tobacco Strips During Controlled Atmosphere Aging

Controlled atmosphere aging(CAA)is a method of tobacco strips aging.Microorganisms,especially bacteria,play an important role in smoking quality of tobacco during the aging process.In order to study the alteration of bacterial community structure in tobacco strips during the process of CAA,the diversity of bacterial 16S rDNA sequences were carried out.36 samples were compared by using Illumina MiSeq sequencing platform in three stages including the mildew and insect control stage(S1),the aging stage(S2)and the quality guarantee stage(S3).The results showed that the species richness and diversity of bacteria in tobacco strips increased from S1 to S3.The dominant populations of tobacco strips in S1 were Sphingomonas,Pseudomonas and Methylobacterium,with a proportion of which gradually decreased during the whole process of CAA.The dominant populations in S2 were Bacillus,Burkholderia and Sphingomonas,with a proportion of Bacillus and Burkholderia increased first and then decreased in the whole process.The distribution of bacteria population in S3 was more uniform.Nonmetric multidimensional scaling analysis showed that the samples of three aging stages could be distinguished clearly.It was clear that the tobacco strips in CAA process harbored abundant levels of bacteria,and the active microbial groups were different in different aging stages.Sphingomonas,Pseudomonas and Methylbacterium were mainly involved in the early process,while Bacillus and Burkholderia mainly played an important role in the later process.