Chemical composition, antimicrobial and cytotoxic activities of <i>Croton delpyi</i> Gagnep. essential oil from Vietnam

This study aimed to investigate the volatile components of leaf essential oil of <i>Croton delpyi</i> Gagnep. as well as its cytotoxic and antimicrobial activities. Analysis of this essential oil using gas chromatography-mass spectrometry (GC-MS) identified 36 compounds. The main components included β-caryophyllene (54.34%), α-humulene (18.19%), β-caryophyllene epoxide (3.99%), valencene (3.64%), and β-linalool (3.22%). This essential oil showed good antibacterial activity against the <i>Bacillus cereus</i> ATCC 14579 with IC₅₀ values of 69.79±1.21 μg/mL. In addition, the essential oil of <i>C. delpyi</i> leaves exhibited cytotoxic activity against HeLa (human cervical carcinomas, IC₅₀ = 3.51±0.15 μg/mL) and HepG2 (human hepatocellular carcinoma, IC₅₀ = 2.09±0.11 μg/mL) cell lines. This study is the first to document the <i>in vitro</i> antimicrobial and cytotoxic activities of <i>C. delpyi</i> leaf essential oil, thus encouraging further studies on this species.