Ocimum tenuiflorum (synonym Ocimum sanctum), commonly known as holy basil, tulasi (sometimes spelled thulasi) or tulsi, is an aromatic perennial plant in the family Lamiaceae. It is native to the Indian subcontinent and widespread as a cultivated plant throughout the Southeast Asian tropics.<ref name="Staples1999">Template:Cite book</ref><ref name="warrier">Template:Cite book</ref>
Tulasi is cultivated for religious and traditional medicine purposes, and for its essential oil. It is widely used as a 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.
The variety of Ocimum tenuiflorum used in Thai cuisine is referred to as Thai holy basil (Template:Lang-th kaphrao);<ref name="Staples1999"/> it is not to be confused with Thai basil, which is a variety of Ocimum basilicum.
Holy basil is an erect, many-branched subshrub, Template:Convert tall with hairy stems. Leaves are green or purple; they are simple, petioled, with an ovate, up to Template:Convert-long blade 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 elongate racemes .<ref name="warrier"/> The two main morphotypes cultivated in India and Nepal are green-leaved (Sri or Lakshmi tulasi) and purple-leaved (Krishna tulasi).<ref>Template:Cite journal</ref>
Origin and distribution
DNA barcodes of various biogeographical isolates of tulsi from the Indian subcontinent are now available. In a large-scale phylogeographical study of this species conducted using chloroplast genome sequences, a group of researchers from Central University of Punjab, Bathinda, have found that this plant originates from North Central India.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> The discovery might suggest the evolution of tulsi is related with the cultural migratory patterns in the Indian subcontinent.
Significance in Hinduism
Tulsi leaves are part in the worship of Vishnu and his avatars, including Krishna and Rama, and other male Vaishnava deities, such as Hanuman. Tulsi is a sacred plant for Hindus and is worshipped as the avatar of Lakshmi.<ref>Template:Cite web</ref> Traditionally, tulsi is planted in the centre of the central courtyard of Hindu houses or may be grown next to Hanuman temples.<ref>Simoons, pp. 17–18.</ref>Template:Full citation needed
The ritual lighting of lamps each evening during Kartik includes the worship of the tulsi plant, which is held to be auspicious for the home.<ref name="Flood2003">Template:Cite book</ref><ref>Template:Cite book</ref> Vaishnavas traditionally use Hindu prayer beads made from tulsi stems or roots, which are an important symbol of initiation. They have such a strong association with Vaishnavas, that followers of Vishnu are known as "those who bear the tulsi round the neck".<ref name="Simoons">Template:Cite book</ref>
Ayurveda and Siddha
Tulasi (Sanskrit:-Surasa) has been used in Ayurveda and Siddha practices for its supposed treatment of diseases,<ref>Template:Cite book</ref><ref name="BraunCohen2015">Template:Cite book</ref> none of which has been proven by conventional medical research. Traditionally, tulasi is taken as herbal tea, dried powder, fresh leaf or mixed with ghee.Template:Cn
The leaves of holy basil, known as kaphrao in the Thai language (Template:Lang-th), are commonly used in Thai cuisine for certain stir-fries and curries such as phat kaphrao (Template:Lang-th) — a stir-fry of Thai holy basil with meats, seafood or, as in khao phat kraphao, with rice. Two different types of holy basil are used in Thailand, a "red" variant which tends to be more pungent, and a "white" version for seafood dishes.<ref>Template:Cite book</ref><ref>Template:Cite book</ref> Kaphrao should not be confused with horapha (Template:Lang-th), which is normally known as Thai basil,<ref name=katzer>Gernot Katzer's Spice Pages</ref> or with Thai lemon basil (maenglak; Template:Lang-th).
For centuries, the dried leaves have been mixed with stored grains to repel insects.<ref>Template:Cite journal</ref>
Tulsi essential oil consists mostly of eugenol (~70%) β-elemene (~11.0%), β-caryophyllene (~8%) and germacrene (~2%), with the balance being made up of various trace compounds, mostly terpenes.<ref>Template:Cite journal</ref>
The genome of Tulsi plant has been sequenced and reported as a draft, estimated to be 612 mega bases, with results showing genes for biosynthesis of anthocyanins in Krishna Tulsi, ursolic acid and eugenol in Rama Tulsi.<ref>Template:Cite journal</ref>