Available online at www.scholarsresearchlibrary.com Scholars Research Library Archives of Applied Science Research, 2013, 5 (5):33-37 (http://scholarsresearchlibrary.com/archive.html) ISSN 0975-508X CODEN (USA) AASRC9 33 Scholars Research Library Isolation of ursolic acid (3β-hydroxyurs-12-en-28-oic acid) from the leaves of Eucalyptus grandis W. Hill ex Maiden Ibrahim T. Babalola 1,2 , Esther A. Adelakun 2* and Francis O. Shode 3 1 Department of Chemistry, Faculty of Natural Sciences, Yobe State University, Damaturu, Nigeria 2 Department of Chemistry, Faculty of Natural Sciences, University of Jos, Jos, Nigeria 3 Department of Chemistry, Faculty of Sciences and Agriculture, University of Zululand, Kwa Dlangezwa 3886, Republic of South Africa and Research, Innovation & Development Director of Life-Promoters Biosciences (Pty) Ltd, 5 Ferrara Gardens, Westville North 3629, South Africa _____________________________________________________________________________________________ ABSTRACT Ancient people used medicinal plant extract as ingredients in tradomedical portions and poisons. Over time, these traditional treatments have had the chance to become refined based on efficacy and safety. It was therefore hypothesised that plants that were used in the past and are still used today to treat symptoms associated with a particular disease condition are more likely to contain pharmacologically active metabolites than plants that have not been used continuously. The use of E. grandis in traditional medicines has been document. Ursolic acid (3β- hydroxyurs-12-en-28-oic acid) was isolated from the leaves of Eucarlyptus grandis. Column chromatography (normal phase), IR, LC-MS and NMR techniques were employed for the isolation and characterization of the compound. Presence of ursolic acid, a pentacyclic triterpene carboxylic acid in the leaves of E. grandis gives credence to the ethnomedical use of the plant leaves in the treatment of diseases. Keywords: Ethnomedicine, Drug development, Tuberculosis, Natural products, Ursolic acid _____________________________________________________________________________________________ INTRODUCTION Natural products continue to play a most significant role in the drug discovery and development process[1], and plants are recognized as a valuable and inexhaustible source of bioactive metabolites [2]. It is established that drugs derived from plants are known to have lesser side effects than the synthetic drugs. Eucalyptus grandis is a tree belonging to the family Myrtaceae. It is native to the east coast of Australia; It is commonly known as rose gum or flooded gum. The glossy dark green leaves are stalked, lanceolate, and paler on their undersides, 10 to 16 cm (4-6.4 in) long and 2-3 cm (0.8-1.2 in) wide. They are arranged alternately along the branches. The white flowers appear from mid-autumn to late winter from April to August, and are arranged in groups of seven to eleven flower heads. The flowers are followed by small pear-or cone-shaped gumnuts which measure 5-8 mm in length and 4-7 mm across [3-5]. Essential oil extracted from the leaves of E. grandis is reported to have antiseptic and disinfectant properties, decoction of the leaves are used in folklorik treatment of flu, bronchitis, pneumonia and respiratory infections [6].The plant has been reported of high performance index (I P ) in two independent ethnobotanical survey reports of medicinal plants for the treatment of tuberculosis and other respiratory diseases of Nupe tribe of Niger State, Nigeria, and Zulu tribe of Maputuland, KwaZulu-Nata province, Republic of South Africa [7,8]. This paper reports on the occurrence and characterization of ursolic acid in E. grandis.