该研究考察SO3微热爆（SO3 Micro-Thermal Explosion，STEX）预处理辅助提取泰国罗勒挥发油的工艺，并对所得挥发油化学成分和香气轮廓进行比较分析。结果表明：阴干和SD（水上蒸馏）法是最优的干燥方式和提取方法；STEX预处理的最佳工艺为SO3与干物质质量比1:3、预处理温度50 ℃、预处理时间30 min，此条件下挥发油得率为0.56%，相比于SD法和WD（水中蒸馏）法分别提高了41.41%和90.48%；放大验证实验中挥发油得率可进一步提高至0.60%；扫描电镜观察发现STEX预处理后的罗勒表面微观结构发生明显改变，表面皱缩严重，气孔扩张明显；元素和红外分析结果显示，STEX预处理会显著提高罗勒S元素含量（p<0.05），但不影响其化学官能团构成；经GC-MS鉴定，WD、SD和STEX-SD来源的挥发油均以甲基胡椒酚和甲基丁香酚为主，其中，STEX-SD来源的挥发油可鉴定化合物31种，种类最多；感官评价结果表明，三种挥发油均以茴香和柠檬香为主，但STEX-SD来源的挥发油具有更明显的香气。STEX可作为一种预处理方法用于提高罗勒等芳香性植物挥发油的得率和香气品质。

In this study, the SO3 micro-thermal explosion (STEX) pretreatment-assisted extraction process for the volatile oil from Thai basil (Ocimum basilicum var. thyrsiflora) was investigated. The chemical composition and aroma profile of the obtained volatile oil were also analyzed. The results showed that shade-drying and steam distillation (SD) were the best drying method and extraction method. The optimum conditions of STEX were: SO3 to dry matter mass ratio, 1:3; pretreatment temperature, 50 °C; pretreatment time, 30 min. The yield of volatile oil under such conditions was 0.56%, which was 46.41% and 90.48% higher than those of SD and water distillation (WD), respectively. The yield of volatile oil could be further increased to 0.60% in the scale-up validation experiment. Scanning electron microscopic examinations revealed that the microstructure of the STEX-pretreated Thai basil biomass was altered significantly, with severe surface wrinkling and significant stomatal expansion. The results of elemental and IR analyses revealed that the STEX pretreatment increased significantly the sulfur content in the Thai basil biomass without influencing the composition of chemical functional groups. GC-MS analysis revealed that methyl chavicol and methyl eugenol were the main components of the three volatile oils obtained from the basil biomass subjected to WD, SD and STEX-SD, among which, the volatile oil obtained by STEX-SD had the highest number of identified compounds (31 species). The sensory evaluation showed that fennel- and lemon-like notes were the main aromas of the three essential oils, with the aroma of the essential oil obtained by STEX-SD being more obvious. STEX can be used as an efficient pretreatment method to improve the yield and aroma quality of the volatile oils from aromatic plants such as basil.

中央高校基本科研业务费专项资金（JZ2021HGTB0114）；企业委托（W2020JSKF0603）；安徽省重点研究与开发计划（202004a06020041）