The plant and its oil contain diverse phytochemicals, including tannins, flavonoids, eugenol, caryophyllenes, carvacrol, linalool, camphor, and cinnamyl acetate, among others.^[9][10] One study reported that the plant contains an eponymous family of 10 neolignan compounds called tulsinol A-J.^[11]

Specific aroma compounds in the essential oil are camphor (32%), eucalyptol (19%), ⍺-bisabolene (17%), eugenol (14%), germacrene (11%) and β-bisabolene (11%).^{[12][better source needed]} In addition, more than 60 different aroma compounds were found through gas chromatography–mass spectrometry analysis of holy basil.^[12] However, other studies have stated tulsi essential oil consists mostly of eugenol (70%) β-elemene (11%), β-caryophyllene (8%), and germacrene (2%), with the balance being made up of various trace compounds, mostly terpenes. Source (Ocimum tenuiflorum - Wikipedia)