Insights into the Composition and Antibacterial Activity of Amomum tsao-ko Essential Oils from Different Regions Based on GC-MS and GC-IMS

Abstract

Chemical components are one of the most significant traits and attributes of plant tissues, and lead to their different functions. In this study, the composition of <i>Amomun tsao-ko</i> essential oils (AEOs) from different regions was first determined by a combination of gas chromatography-mass spectrometry (GC-MS) and gas chromatography-ion mobility spectrometry (GC-IMS). In total, 141 compounds were identified, of which terpenes and aldehydes were the main groups. Orthogonal partial least square discriminant analysis (OPLS-DA) distinguished the samples from different regions clearly, and the main differences were terpenes, aldehydes, and esters. Meanwhile, AEOs showed strong antibacterial activity against <i>Staphylococcus aureus</i> (<i>S. aureus</i>), and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) reached 0.20 mg/mL and 0.39-0.78 mg/mL, respectively. From correlation analysis, 1,8-cineole, (E)-dec-2-enal, citral, α-pinene, and α-terpineol were determined to be the potential antibacterial compounds. This study provides the basis for the variety optimization of <i>A. tsao-ko</i> and its application as a natural food preservative.