Evaluation Of Microbial Function Of Tobacco Leaves Around Qinling Mountains And Establishment Of Microbial Library For Dominant Aroma Enhancing Microorganism

Because of its unique geographical location and favorable climate,the area of Qinling Mountains is an important quality tobacco production area in China,which plays an important role in local economic growth.Through the collection of leaf samples from the Qinling area,the microbial screening of tobacco leaves was carried out,and the degradation ability of some macromolecular substance was evaluated.The strains with strong functionality were identified by molecular biology and classified.Through the cultivation of the dominant functional strains,and after spraying to the tobacco fermentation,the samples were sent to Shaanxi Tobacco Industry Co.,Ltd.for expert evaluation and obtained the aroma-enhancing microorganism using for the microbial library establishment.1.A total of 39 samples of high quality tobacco leaves were collected from the different six cities in the Qinling Mountains area.A total of 594 strains were obtained from 39 samples,including 118 strains of fungus,18 strains of actinomycete and 458 strains of bacterium.And the ratio of bacteria is 77.10%,which is dominant microorganism.Regardless of origin from where each origin in tobacco samples of isolated strains were bacterium more than fungus and actinomycete.The number of actinomycete was the least,and some origin such as Hanzhong South Zheng County and Yan'an Fu County Chafang Town Xigoumen village did not obtain actinomycete.It is possible that samples in these places are not conducive to actinomycete growth.Difference varieties can cause the difference of microbial components in the samples.According to the influence of different species on microbial flora,it can provide a reference for the screening of strains.The leaf part of tobacco leaves has a great effect on the microbial flora,and most of the microorganism were distributed in the lower and middle part of the leaves.For microbial distribution,bacterium was still the most.2.Based on the degradation ability of starch,protein,cellulose,pectin,and other macromolecule substances or aroma precursors,the ability of plant-derived microorganism was classified.234 strains were able to degrade the protein,there were 151 strains of the degradation index was more than or equal to 2,42 strains greater than or equal to 3,16 strains were greater than or equal to 4.86 strains had the ability to degrade starch,and there were 28 strains of the degradation index was more than or equal to 2.46 strains with the ability to degrade cellulose,there were 28 strains of the degradation index was greater than or equal to 2.13 strains with the ability to degrade pectin,the degradation index greater than or equal to 2 of 3 strains.20 strains with the ability to degrade xylan,and there were 7 strains with the index greater than or equal to 2.46 strains had the ability to degrade N-nitrosamine(TSNA),10 strains with good degradation effect,and 36 strains with ordinary effect.3.The corresponding strains were screened for identification and tobacco fermentation,and the samples were sent to Shaanxi Zhongyan Industry Co.,Ltd.,and 16 strains of positive strains were obtained by expert group.For strains with positive aroma effect,the maximum increase was 5.67% of 3 strains,strain number 371,378,253.Wherein strain 371 belongs to Bacillus.Strain 378 belongs to Enterobacter,and strain 253 belongs to Enterobacter.The strain 176 increased to 4.54%,slightly higher than 190 and 385.Strain 176 belongs to Bacillus,385 belongs to Pseudomonas and strain 190 belongs to Bacillus.In addition,strain 399 also reached to 2.27%,which belongs to Bacillus.Strain 474,681,408,120,379,251,438,677 and 695 belong to Enterobacter,Alcaligenes and so on.Compared with the control of CK,the average growth rate of less than 1%,so the effect was not very obvious,all kinds of macromolecule material degradation ability was ordinary.For strains with negative aroma effects,strain 679,279,163,131,500,84,26,113,66,685,133,688 had more or less negative effects,with the largest negative effect was strain 113.The negative effect was strain 163,131,685,133,the rate of increase was-0.23%,and mostly belong to Bacillus,Enterobacter.