陈化烤烟叶面优势菌的筛选鉴定与其增香效应

Identification of dominant and fragrance-enhancing microorganisms of tobacco leaves during ripening

【目的】筛选定位出陈化烤烟表面优势微生物,研究其增香效应。【方法】以NC89、中烟100、中烟101三个烤烟品种烟叶为材料,提取烟叶表面微生物总DNA,通过PCR-DGGE技术研究烟叶表面微生物的多样性,筛选定位出优势增质菌。采用恒温恒湿发酵条件研究优势增质菌对发酵烤烟烟叶中香气物质含量的影响。【结果】(1)根据PCR-DGGE图谱显示,3个烤烟品种在不同陈化时期有A、B、C、D、E五条共有的条带;通过进一步的聚类分析、序列测定和Blast分析,筛选定位出一株可培养的优势菌株,巨大芽孢杆菌。(2)经过添加优势增质菌处理后的发酵烟叶中大多数香气成分含量与其对照相比表现为增加趋势,从而验证了优势菌株的增香效应。【结论】由PCR-DGGE技术筛选定位出的陈化烟叶表面优势增质菌,对陈化烤烟具有较为明显的增香效应,为进一步工业化生产和应用提供了理论依据和技术支撑。

[ Objective] We screened dominating microbial species isolated from aging flue-cured tobacco and studied their aroma improving effect. [ Methods] Total DNA of microorganisms from the fermentation flue-cured tobacco surface of NC89 ,ZhongYan 100 and ZhongYan 101 were extracted. Under the PCR-DGGE, the diversity of microorganisms on fermentation tobacco leaves were studied and dominating microbial species were screened. We further studied the influence of dominating microbial species on the content of aroma components of the fermentation flue-cured tobacco. [ Results] 1 ） By using DGGE analysis, there were 5 dominant bands A, B, C, D and E in all tobacco leaves samples of the three varieties; In further studies, five dominant DGGE bands were isolated, cloned and sequenced. From them we screened a dominant microorganism. 2） The content of most aroma components in tobacco leaves increased when they were sprayed with the dominant microorganism, comparing with the control. [ Conclusion] The dominant microorganism can improve the flavor of tobacco leaves during ripening.