Tulsi-तुलसी- Ocimum tenuiflorum

Ocimum tenuiflorum, commonly known as holy basil, tulsi or tulasi, is an aromatic perennial plant in the family Lamiaceae. It is widely cultivated throughout the Southeast Asian tropics. It is native to tropical and subtropical regions of Asia, Australia and the western Pacific. This plant has escaped from cultivation and has naturalized in many tropical regions of the Americas. It is an agricultural and environmental weed.

Tulasi is cultivated for religious and traditional medicine purposes, and also for its essential oil. It is widely used as an herbal tea, commonly used in Ayurveda, and has a place within the Vaishnava tradition of Hinduism, in which devotees perform worship involving holy basil plants or leaves.

Morphology
Holy basil is an erect, many-branched subshrub, 30–60 cm (12–24 in) tall with hairy stems. Leaves are green or purple; they are simple, petioled, with an ovate blade up to 5 cm (2 in) long, which usually has a slightly toothed margin; they are strongly scented and have a decussate phyllotaxy. The purplish flowers are placed in close whorls on elongated racemes.

The three main morphotypes cultivated in India and Nepal are Ram tulsi (the most common type, with broad bright green leaves that are slightly sweet), the less common purplish green-leaved (Krishna or Shyam tulsi) and the common wild vana tulsi (e.g., Ocimum gratissimum).

Phytochemicals

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

Specific aroma compounds in the essential oil are camphor (32%), eucalyptol (19%), ⍺-bisabolene (17%), eugenol (14%), germacrene (11%) and β-bisabolene (11%).[better source needed] In addition, more than 60 different aroma compounds were found through gas chromatography–mass spectrometry analysis of holy basil. 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.