Optimization of Extraction Process for Lysimachia capillipes Extract by Response Surface Methodology and Its Application in Cigarette Flavoring

To develop novel natural flavoring materials for tobacco, the extraction process of Lysimachia capillipes extract was optimized using organic solvent heat reflux extraction, combining single-factor experiments with response surface methodology (RSM). The obtained concrete was further analyzed by gas chromatography-mass spectrometry (GC-MS) for compositional characterization and evaluated through cigarette flavoring application. The results showed that: (1) The optimal extraction conditions were as follows: extraction time of 4 h, ethanol concentration of 70%, and liquid-to-solid ratio of 22 mL/g. Under these conditions, the average yield of Lysimachia capillipes extract reached 11.697% in three validation tests, with a relative error of only 0.328% compared to the predicted value. The significance of factors affecting the yield ranked as ethanol concentration (C)＞liquid-to-solid ratio (A)＞extraction time (B). (2) GC-MS analysis identified 36 volatile compounds in the concrete, including 14 aroma-active substances, accounting for 62.234% of the total volatile components. (3) Through the evaluation of the flavoring effect of single tobacco leaves in cigarettes, it is determined that the most suitable addition amount of the Lysimachia capillipes extract is 10 mg/kg. The process conditions obtained through response surface methodology are feasible, providing a reliable theoretical foundation for the application of Lysimachia capillipes extract in cigarette flavoring.