Indian Journal of Experimental Biology Vol. 44, April 2006, pp. 300-304 Antidiabetic, antihypercholesterolaemic and antioxidant effect of Ocimum sanctum (Linn) seed oil Shweta Gupta a , Pramod K Mediratta b , Surender Singh c , K K Sharma b & Rimi Shukla* a Department of a Biochemistry and b Pharmacology, University College of Medical Science and GTB Hospital, Shahdara, Delhi 110 095, India. c College of Pharmacy (University of Delhi), Pushp Vihar, New Delhi 110 017, India Received 3 June 2005; revised 29 December 2005 Antihyperlipidaemic and antioxidant effect of Ocimum sanctum Linn. seed oil (OSSO) was investigated in rabbits. Administration of OSSO (0.8 g/kg body weight/day) for four weeks, in cholesterol (100 mg/kg body weight/day) fed rabbits significantly decreased serum cholesterol, triacylglycerol and LDL-+VLDL-cholesterol as compared to untreated cholesterol fed group. There was significant fall in atherogenic index in OSSO treated group. In addition, treatment with OSSO decreased lipid peroxidation and increased reduced glutathione content in blood. Antidiabetic effect of O. sanctum seed oil was evaluated in alloxan diabetic rabbits. Two weeks treatment of diabetic rabbits with OSSO (0.8 gm/kg/day) showed no significant hypoglycaemic effect. Results of the present study show that OSSO has hypocholesterolaemic and antioxidant effects but it does not have antidiabetic effect. Keywords: Antioxidant activity, Hypocholesterolaemic agents, Ocimum sanctum, Seed oil. Ocimum sanctum (OS, Family-Labiatae), known as Tulsi in Hindi and Holy basil in English has been extensively used in Ayurvedic system of medicine. Each part of the plant has medicinal value. The juice of the stem and leaves is diaphoretic and expectorant. It relieves earache and is used to treat skin disorders 1 . Efficacy of OS leaves in decreasing blood glucose has also been reported 2,3 . The fixed oil obtained from seeds of OS, is rich in unsaturated fatty acids, it contains (%) palmitic acid (11.69), stearic acid (3.19), oleic acid (13.82), linoleic acid (52.24) and linolenic acid 16.63% 4 . OS seed oil has anti-inflammatory activity which is attributed to linoleic acid present in the oil 4,5 . It was reported to have chemoprotective activity in mice 6 . This effect of OS seed oil is due to scavenging and detoxifying effect on reactive carcinogenic species produced by carcinogen methylcholanthrene. It also had antipyretic, analgesic, immunomodulatory, antiarthritic and hypoglycaemic activity 3,7-9 . Hypolipidaemic and antioxidant activity of OS leaves have also been reported. OS leaf powder supplementation at 1 to 2% dose levels showed significant hypolipidaemic effect in rabbits 10 . Aqueous extract of leaves has been found to protect mouse against radiation lethality and to possess significant antioxidant effect 11-13 . However, so far to our knowledge there are no reports on effect of OS seed oil on serum lipid profile and oxidative stress and there is only one report on hypoglycaemic effect of OS seeds 3 . Therefore, the present study is aimed at assessing antidiabetic, antihypercholesterolemic and antioxidant effects of OS seed oil. Materials and Methods Plant material⎯Dried seeds of O. sanctum collected locally and authenticated by a resident botanist at the Department of Genetics, Indian Agricultural Research Institute, Pusa, New Delhi, were crushed and cold macerated in petroleum ether for three days. The petroleum ether was evaporated from the extract and oil was filtered to clarity. It was then stored at room temperature in amber-coloured light-protected bottles for experimental use. The yield of the oil was 22% v/w. Animals and experimental design⎯Male albino rabbits (1-1.5 kg) were used in the study. They were kept in a 12:12 hr L:D cycle and temperature (22°±2°C) controlled conditions. Standard laboratory pellet diet (Hindustan Lever, Bombay) and water were given ad libitum. The care of the animals was as per the ‘Guidelines for the Care and Use of Animals _____________ *Correspondent author Phone: 91-11-22582971-74 Extn. 229 Fax: 91-11-22590495 e-mail: rimishukla@yahoo.com