A comparative study of Amomum tsaoko hydrosols from different geographical origins: volatile profiles and biological properties

This study systematically investigated the volatile profiles and bioactivities of hydrosols derived from Amomum tsaoko (A. tsaoko) collected from three geographical regions in Nujiang Prefecture. Headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS) identified 79 volatile compounds, with terpenoids constituting the dominant chemical class, accounting for over 80% of the total volatiles. Partial least squares discriminant analysis (PLS-DA) revealed significant compositional differences among the samples from different origins. Nine key discriminatory markers were identified, including eucalyptol, terpinen-4-ol, α-terpineol, neral, geraniol, geranial, (E)-2-decenal, 2,3-dihydro-1 H-indene-4-carboxaldehyde, and methyl palmitate. Importantly, all hydrosols exhibited strong antioxidant activity, with DPPH and ABTS radical scavenging rates exceeding 62.90% and 72.62%, respectively, and achieved more than 99% inhibition of Staphylococcus aureus and Escherichia coli after 12 h of treatment. The antioxidant capacity followed the order Gongshan > Lushui > Fugong, while antimicrobial efficacy followed the order Fugong > Gongshan > Lushui. Mantel test analysis further established significant correlations between the identified discriminatory compounds and the observed bioactivities, suggesting that these specific volatile components may contribute to the respective biological properties. These findings deepen the understanding of the chemical diversity and functional properties of A. tsaoko hydrosols and provide fundamental information for future research on their value-added utilization.