INTERNATIONAL JOURNAL OF AGRICULTURE & BIOLOGY ISSN Print: 1560–8530; ISSN Online: 1814–9596 12–1270/2013/15–4–772–776 http://www.fspublishers.org Full Length Article To cite this paper: Jianu, C., G. Pop, A.T. Gruia and F.G. Horhat, 2013. Chemical composition and antimicrobial activity of essential oils of lavender (Lavandula angustifolia) and lavandin (Lavandula x intermedia) grown in Western Romania. Int. J. Agric. Biol., 15: 772‒776 Chemical Composition and Antimicrobial Activity of Essential Oils of Lavender (Lavandula angustifolia) and Lavandin (Lavandula x intermedia) Grown in Western Romania Călin Jianu 1 *, Georgeta Pop 2 , Alexandra T. Gruia 3 and Florin George Horhat 4 1 Department of Food Science, Faculty of Food Processing Technology, Banat's University of Agricultural Sciences and Veterinary Medicine, Calea Aradului 119, RO-300645 Timisoara, Romania 2 Faculty of Agriculture, Banat's University of Agricultural Sciences and Veterinary Medicine, Calea Aradului 119, RO- 300645 Timisoara, Romania 3 Center for Transplant Immunology, County Hospital Timisoara, Blvd. Iosif Bulbuca 10, RO-300736 Timisoara, Romania 4 Department of Microbiology, Victor Babes University of Medicine and Pharmacy, Timisoara, Romania, 2nd Eftimie Murgu Square, RO-300041 Timisoara, Romania * For correspondence: calin.jianu@gmail.com Abstract The purpose of this study was to determine the chemical composition and antimicrobial properties of essential oils (EOs) isolated from lavender (L. angustifolia Miller) and lavandin (Lavandula x intermedia) harvested in 2011 in western Romania. The essential oils, isolated by steam distillation from inflorescences arrived at full flowering stage, were analyzed by gas chromatography coupled with mass spectrometry (GC-MS). The essential oil of L. angustifolia Miller analyzed contained as main components caryophyllene (24.1%), beta-phellandrene (16%) and eucalyptol (15.6%), while the essential oil of Lavandula x intermedia contains camphor (32.7%) and eucalyptol (26.9%). The antimicrobial activity was evaluated by the Kirby-Bauer method. Antimicrobial tests showed antimicrobial activity against Shigella flexneri, Staphylococcus aureus, E. coli and Salmonella typhimurium, while Streptococcus pyogenes is not sensitive to the action of the two essential oils. The study revealed that essential oils isolated and analyzed from lavender (L. angustifolia Miller) and lavandin (Lavandula x intermedia) display significant bactericidal effects against microorganisms such as Shigella flexneri, Staphylococcus aureus and E. coli even in the absence of active principles like linalool and linalyl acetate, considered responsible for the antibacterial and antifungal properties of essential oils obtained from different species of Lavandula. The results suggest once again that the antimicrobial activity of EOs is a resultant of the antibacterial properties of the major and minor components in their chemical composition. © 2013 Friends Science Publishers Keywords: Lavender; Lavandin; Essential oil; Steam distillation; GC-MS analysis; Antimicrobial activity Introduction L. angustifolia Miller or true lavender is a perennial shrub of the family Lamiaceae (Lis-Balchin, 2002). The main growing countries are Bulgaria and France and on smaller areas in Morocco, the former republics of Yugoslavia, Hungary, Italia, Russia, Spain, Romania, Ukraine, Turkey, and others (Zheljazkov, 2012). Their main use is the extraction of the essential oil (EO) isolated from flower heads harvested in July-August and processed fresh. The yield is between 0.6-1% (Burdock, 1998). Lavandula × intermedia (lavandin) is a sterile hybrid obtained from L. angustifolia Miller and L. latifolia (L.) (spike lavender) (Raghavan, 2007). Lavandin was produced to serve as raw material to obtain EO. Its yield of EO can be five times higher than that of L. angustifolia (Lis-Balchin, 2002). The EO obtained from L. angustifolia flowers is composed primarily of linalyl acetate, linalool, lavandulol, 1,8-cineol, lavandulyl acetate and camphor (Lis-Balchin and Hart, 1999), while the EO from L. x intermedia contains linalool, linalyl acetate, camphor, 1,8-cineol and borneol (Lis-Balchin, 2002). The EO obtained from L. angustifolia has various medical applications due to its sedative, carminative, anti- depressive and anti-inflammatory properties (Cavanagh, 2005), while the oil isolated from L. x intermedia due to its high content of camphor is used mainly in the production of perfumes and soap (Lis-Balchin, 2002). In addition to these applications, both EOs are used in the food industry as natural flavorings in baked goods, alcoholic and nonalcoholic beverages, puddings etc. (Burdock, 1998). Besides these properties numerous studies have reported that both EOs possess antimicrobial and cytotoxic