Hindawi Publishing Corporation he Scientiic World Journal Volume 2013, Article ID 943598, 6 pages http://dx.doi.org/10.1155/2013/943598 Research Article A New Source of Elemol Rich Essential Oil and Existence of Multicellular Oil Glands in Leaves of the Dioscorea Species Joy I. Odimegwu, 1,2 Olukemi Odukoya, 2 Ritesh K. Yadav, 1 C. S. Chanotiya, 1 Steve Ogbonnia, 2 and Neelam S. Sangwan 1 1 Metabolic and Structural Biology Department, CSIR-Central Institute of Medicinal and Aromatic Plants (CIMAP), Lucknow, UP 226015, India 2 Department of Pharmacognosy, Faculty of Pharmacy, College of Medicine Campus, University of Lagos, Lagos, Nigeria Correspondence should be addressed to Neelam S. Sangwan; sangwan.neelam@gmail.com Received 26 August 2013; Accepted 1 October 2013 Academic Editors: Y.-C. Huang and A. Surguchov Copyright © 2013 Joy I. Odimegwu et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Dioscorea species is a very important food and drug plant. he tubers of the plant are extensively used in food and drug purposes owing to the presence of steroidal constituent’s diosgenin in the tubers. In the present study, we report for the irst time that the leaves of Dioscorea composita and Dioscorea loribunda grown under the ield conditions exhibited the presence of multicellular oil glands on the epidermal layers of the plants using stereomicroscopy (SM) and scanning electron microscopy (SEM). Essential oil was also isolated from the otherwise not useful herbage of the plant, and gas chromatographic-mass spectroscopy analysis revealed conirmation of the essential oil constituents. Out of the 76 compounds detected in D. loribunda and 37 from D. composita essential oil, major terpenoids which are detected and reported for Dioscorea leaf essential oil are -terpinene, nerolidol, citronellyl acetate, farnesol, elemol, -farnesene, valerenyl acetate, and so forth. Elemol was detected as the major constituent of both the Dioscorea species occupying 41% and 22% of D. Floribunda and D. composita essential oils, respectively. In this paper, we report for the irst time Dioscorea as a possible novel bioresource for the essential oil besides its well-known importance for yielding diosgenin. 1. Introduction Dioscorea commonly referred to as yam is a monocotyledon- ous tuber plant of the family Dioscoreaceae with about 600 species recorded so far. Diferent species originate from dif- ferent parts of the world: Africa, Asia, the Caribbean’s South America, and the South Paciic islands, and so forth. he dominant zone for yam production in the world is in West Africa [1], where about 48 million tonnes (about 93% of the world’s production) are cultivated on 4 million hectares annually, and mainly in ive countries—Benin, Cˆ ote d’Ivoire, Ghana, Nigeria, and Togo (FAO, 2005) feeding about 100 million people in the tropics [1]. he more domesticated and cultivated ones are native to Africa [2]. Yams, especially the wild species: D. loribunda, D. composita, D. dumetorum, and D. villosa, and so forth are essentially orphan crops and are therefore classiied as neglected and under-utilised species (NUS) due to the fact that though they are rich in nutrients, phytochemicals [3], they are also important in strategies to alleviate biotic and abiotic stresses linked to climate change and are important in traditional pharmacology but yet are adapted to low input agriculture. Yam extracts are emerging as good candidates for the treatment of certain illnesses, for example, menopausal symptoms and some forms of cancer [4]. It is also suggested that yam might reduce the risk of breast cancer and cardiovascular diseases in postmenopausal women [4]. Essential oils usually occur as mono- and sesquit- erpenoids in plants and are important commodities and used for centuries medicinally and as cosmetics [5]. he oil glandu- lar trichomes are the primary sites of essential oil biosynthesis [6–10]. Multicellular peltate and single celled capitate glands contribute signiicantly to the biosynthesis and accumulation of essential oil content [8, 9, 11]. Essential oils with therapeutic efects have been reported in tubers of some yam species: D. alata, rhizomes of D. japonica [12]. Metabolic engineering of monoterpene biosynthesis in the model plant tomato and