Moldogenicity of dominant culturable molds in cigar tobacco leaves and GC-IMS-based analysis of volatile organic compounds.

Introduction: Cigar tobacco leaves (CTLs) are nutrient-rich and susceptible to mold contamination during fermentation and storage. This study aims to investigate the specific volatile profiles of dominant culturable molds recovered under the applied isolation conditions in CTLs and to establish a robust volatile organic compounds (VOCs)-based targeted monitoring strategy for preventing early-stage mold outbreaks. Methods: Eight dominant culturable molds were isolated from natural mold CTLs, and their spores were inoculated onto sterile CTLs. A combined visual scoring and mold counting system was utilized to evaluate the mold-inducing potential of the isolates. Gas chromatography-ion mobility spectrometry (GC-IMS) was employed to detect VOCs at the initial stage of visible mold onset. Furthermore, multivariate chemometric analyses, including principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), were performed to process the data and screen for differential markers. Results: Based on the evaluation system, the isolates were quantitatively classified into high-moldogenicity ( Conclusion: GC-IMS serves as a rapid and effective analytical tool for profiling dynamic VOC changes during fungal infection. The newly identified broad-spectrum markers and the quantitative classification model offer a promising targeted monitoring strategy to ensure safe cigar tobacco production.