Aromatic Cymbopogon grasses are valued for their culinary and medicinal applications, yet most species remain underexplored compared to C. citratus. In this study, the aroma profile of leaves from 4 Cymbopogon species (C. citratus, C. nardus, C. martini and C. procerus) was characterized using headspace-SPME-GC-MS-based analysis alongside lemongrass essential oil identifying 44 volatiles. C. citratus, C. nardus, C. procerus, and lemongrass oil were rich in aldehydes, predominantly citral isomers, neral (24.6–33.9%) and geranial (38.5–57.1%), while geraniol alcohol (86.6%) characterized C. martini. Multivariate data analyses were utilized for species classification but failed to reveal geographical origin. The vapor-phase antibacterial activity of Cymbopogon leaves, lemongrass oil, and citral was evaluated against multidrug-resistant ESKAPE pathogens (Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter cloacae). Each specimen revealed inhibition of all Gram-positive and Gram-negative bacteria except E. faecalis, for which only one C. citratus (ctr3) and lemongrass oil were effective at vapor-phase minimum inhibitory concentration (VP-MIC) 1.57 mg/mL and 0.1 µg/mL, respectively. Lemongrass oil showed higher activity than citral against K. pneumoniae (0.05 vs. 0.1 µg/mL) and A. baumannii (0.08 vs. 0.12 µg/mL). The composition of C. procerus aroma is revealed for the first time along its antibacterial effects.
Wahdan et al. (Fri,) studied this question.