Seeds of Ocimum sanctum L. (Labiatae; popularly known as 'Tulsi' in Hindi and 'Holy Basil' in English) contain a pale yellow colored fixed oil. The oil possesses antiinflammatory activity due to dual inhibition of arachidonate metabolism supplemented by antihistaminic activity. The antiinflammatory activity is not dependent on the pituitary adrenal axis. The oil possesses
antipyretic activity due to
prostaglandin inhibition and peripherally acting
analgesic activity. The oil has been found to be effective against
formaldehyde or adjuvant induced
arthritis and
turpentine oil induced joint
edema in animals.
Lipoxygenase inhibitory,
histamine antagonistic and antisecretory activities of the oil contribute towards antiulcer activity. The oil can inhibit enhancement of vascular capillary permeability and leucocyte migration following inflammatory stimulus. The LD50 of the oil is 42.5 ml/kg and long-term use of oil at 3 ml/kg dose does not produce any untoward effects in rats. The oil contains a-
linolenic acid, an
omega-3 fatty acid, which on metabolism produces
eicosapentaenoic acid and the same appears to be responsible for the
biological activity. The oil has hypotensive,
anticoagulant and immunomodulatory activities.
Antioxidant property of the oil renders metabolic inhibition,
chemoprevention and hypolipidaemic activity. Presence of
linolenic acid in the oil imparts antibacterial activity against Staphylococcus aureus. The oil alone or in combination with
cloxacillin, a beta-lactamase resistant
penicillin, has been found to be beneficial in
bovine mastitis, an inflammatory disorder resulting from
staphylococcal infection. Existence of anti-inflammatory,
analgesic and antibacterial activities in single entity i.e. fixed oil appears to be unique.