_____________________________________________________________________________________________________ *Corresponding author: E-mail: annamaria.buschini@unipr.it; European Journal of Medicinal Plants 12(3): XX-XX, 2016, Article no.EJMP.22888 ISSN: 2231-0894, NLM ID: 101583475 SCIENCEDOMAIN international www.sciencedomain.org Inhibitory Activity of Leaves Extracts of Citrullus colocynthis Schrad. On HT29 Human Colon Cancer Cells Belsem Marzouk 1 , Francesca Mussi 2 , Chaima Alaoui Jamali 3 , Serena Galati 2 , Khalid Bekkouche 3 , Mahjoub Aouni 1 , Laura Arru 4,5 , Zohra Marzouk 6 and Annamaria Buschini 2* 1 Laboratoire des Maladies Transmissibles et Substances Biologiquement Actives, Faculté de Pharmacie, Monastir, Rue Avicenne 5000 Monastir, Tunisie. 2 Department of Life Sciences, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy. 3 Laboratoire Biotechnologies, Protection et Valorisation des Ressources Végétales, Equipe Phytochimie et Pharmacologie des Plantes Aromatiques et Médicinales, Département de Biologie, Faculté des Sciences-Semlalia, BP: 2390, 40000, Marrakech, Morocco. 4 Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy. 5 Unité de Pharmaco-économie et Développement des Médicaments, Laboratoire de Biologie Végétale et Laboratoire de Pharmacologie, Faculté de Pharmacie, 5000 Monastir, Tunisie. 6 Interdepartmental Research Centre Biogest-Siteia, via Amendola 2, 42122 Reggio Emilia, Italy. Authors’ contributions This work was carried out in collaboration between all authors. Authors AB, BM and FM designed the study, performed the statistical analysis, wrote the protocol and wrote the first draft of the manuscript. Authors BM, FM, CAJ, SG, KB, LA and ZM managed the analyses of the study and the literature searches. Author AB had primary responsibility for the final content. All authors read and approved the final manuscript. Article Information DOI: 10.9734/EJMP/2016/22888 Editor(s): (1) (2) Reviewers: (1) (2) (3) Complete Peer review History: Received 3 rd November 2015 Accepted 10 th December 2015 Published 30 th January 2016 Original Research Article