Bacterial diversities on unaged and aging flue-cured tobacco leaves estimated by 16S rRNA sequence analysis

Abstract

Flue-cured tobacco leaves (FCTL) contain abundant bacteria, and these bacteria play very important roles in the tobacco aging process. However, bacterial communities on aging FCTL are not fully understood. In this study, the total microbial genome DNA of unaged and aging flue-cured tobacco K326 were isolated using a culture-independent method, and the bacterial communities were investigated by restriction fragment length polymorphism analysis. Comparison of the number of operational taxonomic units (OTUs) between the cloned libraries from the unaged and aging FCTL showed that the microbial communities between the two groups were different. Fifty and 42 OTUs were obtained from 300 positive clones in unaged and aging FCTL, respectively. Twenty-seven species of bacteria exist in both the unaged and aging FCTL, Bacillus spp. and Pseudomonas spp. were two dominant genera in FCTL. However, 23 bacterial species were only identified from the unaged FCTL, while 15 species were only identified from the aging FCTL. Interestingly, more uncultured bacteria species were found in aging FCTL than in unaged FCTL.

Microbial Contamination Of Locally-Prepared Snuff Sold At Eke-Awka Market, Anmbra State, Nigeria

“…The bacteria were Corynebacterium bovis, Micrococcus luteus, Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis and Pseudomonas aeruginosa while the fungi were Aspergillus niger, Rhizopus stolonifer, Alternaria alternata, Geotrichum candidum, Aspergillus flavus and Penicillium italicum ( Table 2). Rubinstein and Pederson [15] and Yang et al [16] isolated bacteria, yeasts and molds in their different types of snuff. Pseudomonas aeruginosa and Staphylococcus aureus were also identified in bacteriological examinations of the sputum samples of a patient with chronic bronchitis.…”

“…The patient used snuff and it was theorized that the snuff might have been the source of the pathogens. A study was undertaken on twenty one samples of previously unopened packs of snuff [16]. They isolated Bacillus subtilis, Staphylococcus aureus, Staphylococcus albus and Pseudomonas aeruginosa.…”

Dissipation and Residues of Myclobutanil in Tobacco and Soil Under Field Conditions

“…Meanwhile, the residues detected in soil reached below 0.045 mg/kg 21 days after the last treatment. As the cured tobacco leaves are not suitable for cigarette products because of its disagreeable odor and undesirable aroma, the aging process of tobacco is necessary after flue-curing, which is a key step to improve tobacco aroma quality and to increase its usability (Huang et al 2010). Normally, the cured tobacco leaves need to be aged for 2-3 years before they are manipulated again.…”

Differences in the Bacteriome of Smokeless Tobacco Products with Different Oral Carcinogenicity: Compositional and Predicted Functional Analysis

“…Early reports, mostly by investigators of the tobacco industry, performed identification and quantification of bacteria and fungi in fresh and processed tobacco, using cultivationbased methods [15]. Recently, 16S rRNA-based techniques including random fragment length polymorphism (RFLP), denaturing gradient gel electrophoresis (DGGE), single strand conformation polymorphism (SSCP) and sequencing have been used to characterize bacterial communities in fresh and cured tobacco leaves as well as those associated with tobacco fermentation process [16][17][18][19][20]. These studies revealed great deal of diversity and differences in the composition of microbiota associated with the different forms of tobacco.…”