Table 1.

Major active chemical constituents of some important essential oils with molecular structure and plant sources.

Essential Oil Constituents	Examples	Chemical Formula	Molecular Structure	Plant Source	Reference
Terpenes	α-Pinene	C10H16		Piper nigrum	[23]
	Limonene	C10H16		Aloysia triphylla	[24]
	Sabinene	C10H16		Oenanthe crocata	[25]
	p-Cymene	C10H14		Thymus fontanesii	[26]
Terpenoids	Linalool	C10H18O		Citrus limon	[27]
	Thymol	C10H14O		Thymus fontanesii	[26]
	Menthol	C10H20O		Aetheroleum menthae piperitae	[28]
	Carvacrol	C10H14O		Zataria multiflora	[29]
Aldehydes	Cinnamaldehyde	C9H8O		Cinnamomum zeylanicum	[23]
Phenols	Eugenol	C10H12O2		Syzygium aromaticum	[23]
	Chavicol	C9H10O		Ocimum ciliatum	[30]