However, sesquiterpene ( I Z i ) I i -farnesene (9.0%) and monoterpene I i -pinene (8.4%) in the stem oil are higher than those in the leaf oil by 6.6 and 7.5%, respectively. Papuanone is a well-known -triketone, which established a great role in the essential oils of the I Myrtaceae i species, while grandiflorene was characteristic of the essential oils of the Lamiaceae or Hypericaceae plants [[14]-[16]]. Our current study first reports the chemical identification of the essential oils of the Vietnamese I Z. begoniifolia i leaf and stem, as well as their antimicrobial activity.