Abstract: In order to improve the sensory smoking quality of tobacco stem extract, the resting cell microbial fermentation technology was used to study the ability of Bacillus velezensis HF-09 to degrade tobacco stem cellulose into sugar and the characteristics of its directional transformation to produce aroma. The results showed that after 10 days of the solid fermentation of Hongda tobacco stem (C3F),the degradation rates of the cellulose and hemicellulose were 18.98% and 30.32%,respectively,while the total sugar and reducing sugar content increase rates were 20.10% and 21.39%,respectively.After the conventional fermentation and the resting cell fermentation treatment using strain HF-09,the total sugar content increased by 8.61% and 47.18%,and the reducing sugar content increased by 6.11% and 38.80%.Resting cell fermentation could significantly increase the content of myristic acid,pentadecanoic acid,hexadecanoic acid and methyl palmitate of the tobacco stem extract,and the increase rates were 442.64%,248.40%,165.50%,153.64%.The bacterium had the ability to efficiently degrade tobacco stem cellulose into sugar under mild conditions.At the same time, the strain HF-09 resting cell fermentation process had higher conversion efficiency and aroma generation rate, more metabolic specificity, suitable for high-quality tobacco stem extract treatment, and had potential application prospects.

Key words: Resting cell fermentation, Bacillus velezensis, Tobacco stem, Aroma components, Solid fermentation, Cellulose, Tobacco flavoring

摘要： 为改善烟梗浸膏的感官抽吸品质，采用休止细胞微生物发酵技术研究贝莱斯芽孢杆菌（Bacillus velezensis）HF-09降解烟梗纤维素转化成糖能力及其定向转化生香的特点。结果表明，对红大烟梗（C3F）固体发酵10 d后，纤维素、半纤维素降解率分别18.98%、30.32%;总糖、还原糖含量增长率分别20.10%、21.39%。采用菌株HF-09常规发酵和休止细胞发酵处理后，烟梗浸膏中总糖含量分别提升8.61%和47.18%，还原糖含量分别提升6.11%和38.80%。休止细胞发酵更能显著提高烟梗浸膏中肉豆蔻酸、十五酸、十六酸、棕榈酸甲酯含量，使其分别提升442.64%、248.40%、165.50%、153.64%。该菌具有在温和条件下高效降解烟梗纤维素转化生糖的能力。同时，菌株HF-09休止细胞发酵工艺的转化效率和生香率更高，更具有代谢专一性，适合高品质烟梗浸膏处理，具有潜在的应用前景。

关键词: 休止细胞发酵, 贝莱斯芽孢杆菌, 烟梗, 致香成分, 固体发酵, 纤维素, 卷烟加香