J. of Advancement in Medical and Life Sciences Volume 3/Issue 3 ISSN: 2348-294X 1 In vitro Antioxidant Activity of Essential Oil and Polar and Non-Polar Extracts of Ocimum canun from Mbuji-Mayi DR Congo D. D. Tshilanda, D.V. Onyamboko 1 , D.S.T. Tshibangu 1 , K.N. Ngbolua 2 , P. V. Tsalu 1 , P.T. Mpiana 1* , 1 Department of Chemistry, Faculty of Science, University of Kinshasa, P.O. Box 190 Kinshasa XI, Democratic Republic of the Congo 2 Department of Biology, Faculty of Science, University of Kinshasa, P.O. Box 190 Kinshasa XI, Democratic Republic of the Congo. *Corresponding author: Mpiana P.T, Phone: +243818116019, e-mail: ptmpiana@yahoo.fr Received: July 25, 2015, Accepted: September 17, 2015, Published: September 17, 2015. ABSTRACT DPPH radical scavenging activity of essential oil from fresh leaves of Ocimum canum Sims as well as methanolic, ethyl acetate, dichloromethane and n-hexane crude extracts, from dried leaves were analysed. The methanolic extract has the low IC50 so the strongest radical scavenging activity among extracts of Ocimum canum with IC50 values of 0.0234 mg.mL -1 . Ethyl acetate , Dichloromethane and essential oil showed respectively IC50 values of 0.0767, 0.1938 and 1.4217 mg.mL -1 . So, polar extracts exhibited stronger antioxidant activity than none-polar ones. None-polar solvents have provided fewer extraction yields than polar. The GC-MS analysis of the essential oil of Ocimum canum has been done and led to the identification of 1,8-Cineole as major compound Keyword: antioxidant activity, Ocimum canum, essential oil, polar and non-polar extracts INTRODUCTION: Oxidation process is one of the most important roots for producing free radicals in food, drugs and even living systems. Reactive oxygen species may be the causative factor involved in many human degenerative diseases, and antioxidant compounds are known to have some degrees of preventive and therapeutic effects of these desorders [1]. Out of vitamins E and C, several molecules have antioxidant potential. However , their effectiveness is sometimes questionable . This is particularly the case of pro -oxidant properties assigned to them and which constitute one of the factors that restrict trade in food and cosmetic products of these compounds; which justifies the renewed attention given to this area [2]. In Africa, about 80 % of the population rely for reasons of poverty to plants for healing [3-5]. Indeed, plants produce a diverse range of secondary metabolites that can be therapeutic. It is in this framework that the research is undertaken in the hope of identifying effective active ingredients. Our research team listed, a number of plants used in traditional medicine against sickle cell disease in Democratic Republic of Congo and tested their antisickling activity among which some species of Ocimum genius [3-20]. Ocimum , is a versatile aromatic genus (family-Lamiaceae) well known for medicinal properties and also for economically important essential oils. The genus is very variable and possesses wide range of intra- and inter-specific genetic diversity [21,22]. Ocimum canum is a small erect plant, with a strong aromatic flavor and is commonly cultivated for culinary purposes. The plant is used in the treatment of various diseases such as cold, fever, parasitic infestations on the body and inflammation of joints headaches. The plant acts as stimulant, carminative, and diaphoretic and leaves as bechic, febrifuge and are used in cold, bronchitis, externally in skin disease. The antifungal property is shown by the essential oil of Ocimum canum Sims. The seed is effective as a hypoglycaemic; also used in the treatment of leucorrhoea and other diseases of urinogenital system. The essential oil at the flowering stage contains citral as a major component along with methylheptenone, methylnonylketone and camphor. Leaves yield beta- sitosterol, betulinic acid and ursolic acid and flavanois, pectolinarigenin-7-methylether and nevadensin [23] In our previous work, the antisickling activity of different extracts from Ocimum canum Sims was studied, but radical scavenging activity has not be done [6]. The aim of this study, to evaluate the antioxidant potential of essential oil and extracts from fresh and dried leaves of Ocimum Canum Sims using the reduction of DPPH radical as bioassay. MATERIELS AND METHODES Plant material Plant samples used in this works (leaves of Ocimum canun) were harvested in the vicinity of Mbuji-mayi city in the central part of DRC on May 2013. The collected materials were identified and deposited at herbarium of the Faculty of Science, University of Kinshasa. Oil distillation Extraction of essential oil from leaves of Ocimum Canum has been done by hydrodistillation. A well-known amount (200g) of a fresh leaves were ground and immersed in a 500 mL round bottom flask of water and hydrodistilled. Water and essence are recovered in a decant bowl, anhydrous magnesium sulphate was used for drying trace of water and then stored in a dark glass bottle at 4 ºC, before submitting it to GC-MS analysis. The process is repeated more time for increasing amount of oil [24]. JOURNAL OF ADVANCEMENT IN MEDICAL AND LIFE SCIENCES Journal homepage: http://scienceq.org/Journals/JALS.php Research Article Open Access