Afieroho & Ugoeze Trop J Pharm Res, November 2014; 13(11): 1911 Tropical Journal of Pharmaceutical Research November 2014; 13 (11): 1911-1915 ISSN: 1596-5996 (print); 1596-9827 (electronic) © Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, 300001 Nigeria. All rights reserved. Available online at http://www.tjpr.org http://dx.doi.org/10.4314/tjpr.v13i11.20 Original Research Article Gas Chromatography-Mass Spectroscopic (GC-MS) Analysis of n-Hexane Extract of Lentinus tuber-regium (Fr) Fr (Polyporaceae) Syn Pleurotus tuber regium Fr sclerotia OE Afieroho 1 * and KC Ugoeze 2 1 Department of Pharmacognosy and Phytotherapy, 2 Department of Pharmaceutics and Pharmaceutical Technology, University of Port Harcourt, Nigeria *For correspondence: Email: eiarieafieroho@yahoo.com, ozadheoghene.afieroho@uniport.edu.ng Received: 11 December 2013 Revised accepted: 15 September 2014 Abstract Purpose: To identify the chemical constituents of the n-hexane extract of the sclerotia of Lentinus tuber-regium (synonym Pleurotus tuber regium) using gas chromatography-mass spectroscopic (GC- MS) techniques. Methods: The n-hexane extract of the sclerotia of Lentinus tuber regium was obtained by exhaustive Soxhlet extraction and analysed using gas chromatography-mass spectroscopic (MS) techniques. The structures of the identified constituents were confirmed on the basis of their fragmentation pattern in comparison with that obtained from the National Institute of Standards and Technology (NIST) reference library. Results: Seven fatty acids derivatives: heptadecenal, n-hexadecanoic acid, 1-eicosene, linoleic acid, oleic acid, linoleic acid ethyl ester, and octadecanoic acid, and five steroidal triterpenoids: cholesterol, α- ergostenol, anthraergostatetraenol, stigmasterol, and alpha-ergosta-4,6,8(14),22-tetraen-3-one. The major constituents characterised are α-ergosta-4,6,8(14), 22-tetraen-3-one (8.56 %) > Anthraergostatetra-enol (7.19 %), > n-hexadecanoic acid (6.29 %) > linoleic acid (3.69 %). Conclusion: This study shows that L tuber-regium is a veritable source of mono- and poly-unsaturated fatty acids, and ergosterol/provitamin D derivatives which may explain, in part, some of its reported nutraceutical benefits. Keywords: Lentinus tuber-regium, Fatty acids, Steroids, Gas chromatography, Mass spectroscopy Tropical Journal of Pharmaceutical Research is indexed by Science Citation Index (SciSearch), Scopus, International Pharmaceutical Abstract, Chemical Abstracts, Embase, Index Copernicus, EBSCO, African Index Medicus, JournalSeek, Journal Citation Reports/Science Edition, Directory of Open Access Journals (DOAJ), African Journal Online, Bioline International, Open-J-Gate and Pharmacy Abstracts INTRODUCTION Lentinus tuber-regium (Fr.) Fr. (Polyporaceae) Syn. Pleurotus tuber regium Fr. (Pleurotaceae) commonly called the king tuber mushroom is an edible gilled fungus of the Agaricomycetes class. It grows wild in both tropical and subtropical regions of the world. It is a common mushroom in the southern part of Nigeria growing on dry wood, where it produces the large spherical to ovoid sclerotia which sometimes measure up to 30 cm in diameter [1,2]. The sclerotium is dark brown on the outside and white on the inside. Locally, it is called ‘katala’ in Hausa, ‘ike usu’ or ‘ero usu’ in Ibo, ‘awu’ in Igala and ‘umoho’usu’ in Igede (Nigeria). Edible mushrooms are a popular and valuable food, low in fats but high in minerals, essential amino acids, vitamins and fibres [3]. Some of them produce substances having potential medicinal effects attributed to the presence of