Indian Journal of Traditional Knowledge Vol. 15(3), July 2016, pp. 425-432 Comparative study on chemical profiling and antimicrobial properties of essential oils from different parts of Eucalyptus lanceolatus Madhulika Bhagat 1* , Sahil Gupta 1 , Vishawdeep Singh Jamwal 1 , Shipali Sharma 1 , Meenakshi Kattal 1 , Stanzin Dawa 1 , Rani Devi 1 & Kushal Bindu 2 1 School of Biotechnology, University of Jammu, Jammu, J&K-180006, India; 2 India Institute of Integrative Medicine, Jammu, J&K-180001, India E-mail: madhulikasbt@gmail.com Received 27 February 2015, revised 28 January 2016 In this study, essential oils from stem, leaf and bud of Eucalyptus lanceolatus were analysed and chemical profiling was done by Gas Chromatography-Mass Spectrometry (GC-MS). The major components of the oils found to have eucalyptol, alpha pinene, beta pinene, alpha eudesmol and para cymene. Eucalyptol is present in large quantity in bud oil (24.96%) followed by alpha and beta pinene (21.71% and 14.20%, respectively). In stem oil, alpha pinene (32.25%) and beta pinene (19.20%) are present in good quantity. In leaf oil, along with alpha and beta pinene, alpha eudesmol is present in good amount. These essential oils also exhibited potent antifungal and antibacterial activities. Further, antimicrobial and antioxidant constituents of the oils were spotted by bio-autography technique. In addition to this, in vitro DPPH radical scavenging activity and metal ion chelation potential of these oils were also investigated and found out that the bud oil has remarkable scavenging potential with IC 50 value of 175μl/ml, followed by leaf and stem oil. Keywords: Essential oil, Chemical profiling, Antioxidant, Antimicrobial, Eucalyptus IPC Int. Cl. 8 : A23L 27/12, C11B, C09K 15/00, A61K 36/00 According to the World Health Organization “a medical plant” is any plant, which in one or more of its organ contains substances that can be used for the therapeutic purposes or which, are precursors for the synthesis of useful drugs, it also defines medicinal plants as herbal preparations produced by subjecting plant materials to extraction, fractionation, purification, concentration or other physical or biological process which may be produced for immediate consumption or as a basis for inherent active ingredients used to cure diseases or relieve pain 1 . The medicinal properties of plants could be based on the antioxidant, antimicrobial and antipyretic effects of the phytochemical present in them 2 . Essential oils are the volatile oils that occur in plants and provide them with a characteristic odour, flavour and a number of other properties. They are complex mixtures that are synthesized within plants as secondary metabolites. These substances are called “essential” because they capture the “essence” of the plant. There is at present growing interest both in the industry and in the scientific research, for aromatic and medicinal plants because of their antimicrobial and antioxidant properties. It may be due to the presence of many active phytochemicals including flavonoids, terpenoids, carotenoids, etc. Phenolic components, present in essential oils, have been known to possess antimicrobial activity and some are classified as Generally Recognized As Safe (GRAS) substances and therefore, could be used to prevent post-harvesting growth of native and contaminant bacteria. The development of bacterial resistance to presently available antibiotics has necessitated the need to search for new antibacterial agents. Eucalyptus (Family Myrtaceae) a native of Australia and commonly known as gum tree, is represented by around 800 species that are distributed throughout the world 3 . Eucalyptus trees are generally tall with evergreen fragrant foliage containing essential oil. The oil is of commercial importance and rank high in quality as well as in quantity and is used in perfumery and pharmaceutical industry. It is composed of a —————— *Corresponding author