The phytochemicals present in plants are responsible for preventing disease and promoting health have been studied extensively to establish their efficacy and to understand the underlying mechanism of their action. Such studies have included identification and isolation of the chemical components, establishment of their biological potency both by in vitro and in vivo studies in experimental animals and through epidemiological and clinical-case control studies in man. Study findings suggest that phytochemicals may reduce the risk of coronary heart disease by preventing the oxidation of low density lipoprotein (LDL) cholesterol, reducing the synthesis or absorption of cholesterol, normalizing blood pressure and clotting, and improving arterial elasticity. Phytochemicals may detoxify substances that cause cancer. They appear to neutralize free radicals, inhibit enzymes that activate carcinogens, and activate enzymes that detoxify carcinogens. They observed that, the Ocimum sanctum Linn has also been suggested to possess, anticancer, anti-diabetic, anti-fertility, antifungal, antimicrobial, cardio protective, analgesic, antispasmodic and adaptogenic actions. Eugenol (1-hydroxy-2methoxy-4-allylbenzene) is the active constituents present in Ocimum sanctum Linn. Indian traditional shrub tulsi (Ocimum sanctums): They unique medicinal plant. They observed that, Ocimum sanctum heals many diseases chronically due to its chemical constituent and believes that it has anti- ageing, immunomodulatory property along with antimicrobial and anticancer property. Phytochemical analysis of aqueous extract of Ocimum sanctum. They observed that, the plant is known to possess antiseptic, analgesic, anti-inflammatory, antimicrobial, antistress, immunomodulatory, hypoglycemic, hypertensive and antioxidant properties. The dried powder of Tulsi (100g) was placed in the thimble of Soxhlet apparatus.500 ml of distilled water was used as a solvent.