O

Scientific name	Name	Description	Picture
Ocimum tenuiflorum	Tulsi or holy basil	It is used for a variety of purposes in traditional medicine; tulsi is taken in many forms: as herbal tea, dried powder, fresh leaf or mixed with ghee. Essential oil extracted from Karpoora tulasi is mostly used for medicinal purposes and in herbal cosmetics.
Oenothera	Evening primrose	Its oil has been used since the 1930s for eczema, and more recently as an anti-inflammatory.
Origanum vulgare	Oregano	Used as an abortifacient in folk medicine in some parts of Bolivia and other northwestern South American countries, though no evidence of efficacy exists in Western medicine. Hippocrates used oregano as an antiseptic, as well as a cure for stomach and respiratory ailments. A Cretan oregano (O. dictamnus) is still used today in Greece as a palliative for sore throat. Evidence of efficacy in this matter is lacking.