# GC-IMS identification of early-warning biomarkers and fungal community dynamics during cigar tobacco mold process

## TL;DR

This study identifies early mold warning signs in cigar tobacco using chemical markers and tracks how fungi change during the mold process.

## Contribution

The study introduces new early-warning biomarkers for mold detection and reveals fungal-VOC interactions during tobacco molding.

## Key findings

- Four VOCs were identified as early-warning biomarkers for mold with significant increases in early stages.
- Fungal diversity dropped sharply after molding, with Aspergillus dominating and correlating with specific VOCs.

## Abstract

Mold-derived contamination in cigar tobacco leaves causes severe economic losses and health risks due to mycotoxin production. This study aimed to identify early-warning biomarkers for mold and elucidate their interaction with fungal communities.

Gas chromatography-ion mobility spectrometry (GC-IMS) combined with high-throughput sequencing was employed to profile volatile organic compounds (VOCs) and fungal communities during artificial molding.

A total of 72 VOCs were detected, with four compounds (2-methyl-1-butanol-M, 2-methyl-1-butanol-D, 2-propanone, and 1-penten-3-ol) identified as early-warning biomarkers through VIP > 1 and P < 0.05, showing 1.31.5-fold increases in early mold stages (MB3). Furthermore, fungal diversity sharply declined post-molding (OTUs reduced by 85.7%), with Aspergillus dominating (>99.45% abundance), and exhibiting strong positive correlations with 1-penten-3-ol (ρ = 0.61) and benzaldehyde-M (ρ = 0.67).

These findings provide actionable biomarkers for industrial mold prevention and insights into fungal-VOC interaction, with implications for perishable crop storage.