An integrated volatilome, lipidome, and mycobiome analysis revealed the aroma differentiation of flue-cured tobacco with different You-fen and aroma types

Tobacco is a major cash crop in China, and its sensory quality is primarily determined by distinct aroma types such as strong-aroma (NX) and mild-aroma (QX), which are closely associated with You-fen (YF). This study employed an integrated volatilome, lipidome, and mycobiome approach to systematically investigate the key components of aroma differentiation in flue-cured tobacco with different You-fen and aroma types (NX and QX). Volatile profiling identified 997 volatile organic compounds across 15 chemical classes, with key aroma-active compounds such as β -damascone, β- ionone, and various esters being significantly enriched in NX flue-cured tobacco. Lipidomics analysis revealed 770 lipid metabolites, demonstrating that Gao-you (GY) flue-cured tobacco accumulated greater amounts of cholesteryl esters and free fatty acids, which serve as critical precursors for aroma compounds biosynthesis. Weighted correlation network analysis further uncovered co-expression modules specifically associated with different types of flue-cured tobacco, highlighting coordinated biosynthetic networks involved in volatile formation. Mycobiome analysis indicated a predominant presence of Sampaiozyma vanillica in NX flue-cured tobacco, whereas QX flue-cured tobacco were characterized by Aspergillus and Abrothallus . Mantel tests confirmed significant correlations between specific microbial taxa and both lipid and volatile profiles. Collectively, the present findings systematically elucidated the interrelationships among volatile compounds, lipid precursors, and microbial communities underlying aroma differentiation in flue-cured tobacco with different YF and aroma types, providing a theoretical foundation for targeted quality improvement in flue-cured tobacco.