Research Article Cytotoxic Constituents from the Rhizomes of Curcuma zedoaria Omer Abdalla Ahmed Hamdi, 1,2 Syarifah Nur Syed Abdul Rahman, 3 Khalijah Awang, 1,2 Norhanom Abdul Wahab, 1,4 Chung Yeng Looi, 1,5 Noel Francis Thomas, 2 and Sri Nurestri Abd Malek 1,3 1 Center for Natural Products and Drugs Discovery (CENAR), University of Malaya, 50603 Kuala Lumpur, Malaysia 2 Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia 3 Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia 4 Biology Division, Center for Foundation Studies in Science, University of Malaya, 50603 Kuala Lumpur, Malaysia 5 Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia Correspondence should be addressed to Sri Nurestri Abd Malek; srimalek@um.edu.my Received 14 February 2014; Accepted 8 June 2014; Published 13 July 2014 Academic Editor: Xin Ming Copyright © 2014 Omer Abdalla Ahmed Hamdi et al. Tis 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. Curcuma zedoaria also known as Temu putih is traditionally used in food preparations and treatment of various ailments including cancer. Te cytotoxic activity of hexane, dichloromethane, ethyl acetate, methanol, and the methanol-soxhlet extracts of Curcuma zedoaria rhizomes was tested on two human cancer cell lines (Ca Ski and MCF-7) and a noncancer cell line (HUVEC) using MTT assay. Investigation on the chemical components in the hexane and dichloromethane fractions gave 19 compounds, namely, labda-8(17),12 diene-15,16 dial (1), dehydrocurdione (2), curcumenone (3), comosone II (4), curcumenol (5), procurcumenol (6), germacrone (7), zerumbone epoxide (8), zederone (9), 9-isopropylidene-2,6-dimethyl-11-oxatricyclo[6.2.1.0 1,5 ]undec-6-en-8-ol (10), furanodiene (11), germacrone-4,5-epoxide (12), calcaratarin A (13), isoprocurcumenol (14), germacrone-1,10-epoxide (15), zerumin A (16), curcumanolide A (17), curcuzedoalide (18), and gweicurculactone (19). Compounds (1–19) were evaluated for their antiproliferative efect using MTT assay against four cancer cell lines (Ca Ski, MCF-7, PC-3, and HT-29). Curcumenone (3) and curcumenol (5) displayed strong antiproliferative activity (IC 50 = 8.3 ± 1.0 and 9.3 ± 0.3 g/mL, resp.) and were found to induce apoptotic cell death on MCF-7 cells using phase contrast and Hoechst 33342/PI double-staining assay. Tus, the present study provides basis for the ethnomedical application of Curcuma zedoaria in the treatment of breast cancer. 1. Introduction It is widely reported that more than 35,000 plant species are used for medicinal purposes worldwide. Of these, 1,200 and 2,000 plant species from Peninsular Malaysia and East Malaysia respectively, are used in folklore medicine [1]. One such plant is Curcuma zedoaria (Berg.) Rosc. belonging to the Zingiberaceae family and known by the locals as Temu putih or Kunyit putih. Te leaf blades are 80 cm long, usually with a purple-brown fush running along the midrib on both surfaces of the leaf. In the young plants, the rhizomes of Curcuma zedoaria are easily confused with those of Curcuma aeruginosa and Curcuma mangga because both have almost similar yellow color. However, a cross-section of the rhizomes of the mature plants of Curcuma aeruginosa is slightly dark purplish whilst Curcuma mangga have brighter yellow color [2]. Temu putih is used by the Malays in the preparation of traditional medicine—consumed either on their own or in mixtures with other plant species. Tey are also widely consumed as spices, as favors in native dishes, and as food preparations in postpartum confnement [2–4]. Curcuma zedoaria also called Er-chu in Chinese is clinically used for the treatment of cervical cancer [5]. In Japan, it has also been used as an aromatic stomachic [6]. Whilst in the Ayurvedic medicine, it is used for the treatment of fevers (cooling), antiseptic, mild expectorant, and deodorizer [7]. In Indonesia, Curcuma zedoaria is widely consumed in the form of “jamu” for the treatment of breast and cervical Hindawi Publishing Corporation e Scientific World Journal Volume 2014, Article ID 321943, 11 pages http://dx.doi.org/10.1155/2014/321943