Research Article Antimicrobial, Cytotoxic, and Anti-Inflammatory Activities of Pimenta dioica and Rosmarinus officinalis Essential Oils Ana Cecilia Lorenzo-Leal, 1,2 Enrique Palou , 2 Aurelio López-Malo , 2 and Horacio Bach 1 1 Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, BC, Canada 2 Chemical and Food Engineering Department, Universidad de las Americas Puebla, San Andres Cholula, Puebla 72810, Mexico Correspondence should be addressed to Horacio Bach; hbach@mail.ubc.ca Received 21 February 2019; Revised 23 April 2019; Accepted 24 April 2019; Published 7 May 2019 Academic Editor: Gail B. Mahady Copyright © 2019 Ana Cecilia Lorenzo-Leal 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. Essential oils (EOs) are natural products composed of a mixture of volatile and aromatic compounds extracted from diferent parts of plants that have shown antimicrobial activities against pathogens. In this study, EOs extracted from Pimenta dioica (Myrtaceae) and Rosmarinus officinalis (Lamiaceae) were assessed for their antimicrobial activities using a panel of pathogenic Gram-positive, Gram-negative, and fungal strains. Te antimicrobial activity was measured by the minimal inhibitory concentration required for the growth inhibition of the microorganisms. Te cytotoxicity of the EOs was tested ex vivo using the model of human-derived macrophage THP-1 cells. In addition, an infammatory response was evaluated using the anti-infammatory cytokine IL-10 and the proinfammatory cytokines IL-6 and TNF-. Results showed that both EOs had antimicrobial activity and diferent pathogens were exposed to concentrations ranging between 600 and 2000 g/mL. In addition, the EOs showed no infammatory activity when exposed to human macrophages, but a potent anti-infammatory activity was measured when the oil from Rosmarinus officinalis was exposed to macrophages. Tis study demonstrates that the use of EOs is an efective alternative for pathogenic bacterial and fungal control, alone or in combination with antibiotic therapy. Moreover, the oil extracted from Rosmarinus officinalis could be used as potent anti-infammatory agent. 1. Introduction Antibiotics are molecules used to treat infectious diseases. Te appearance of multidrug-resistant strains of pathogens has alerted the scientifc community and health care systems worldwide because of the lack of treatment for microbial- related illnesses [1, 2]. Tis threat has also been increased because of the misuse of antibiotics [3]. Natural products have been used in traditional medicine to treat infectious diseases since ancient times. Over the last few decades, the antimicrobial activity of these products has been scientifcally validated [4]. Essential oils (EOs) are a mixture of volatile and aromatic compounds extracted from diferent parts of plants. EOs extracted from plants such as basil, cilantro, eucalyptus, and oregano have shown antimicrobial activities [5–7], including their potential to protect foods against pathogenic microor- ganisms [4, 8, 9]. Leaves of the tree Pimenta dioica (PD) (Myrtaceae) are used as ingredients in many cuisines worldwide. In addition, it has been used in traditional medicine to treat diferent illnesses [10–12]. Rosmarinus officinalis (RO) (Lamiaceae) is an herb used worldwide in cuisine, and it can also be used in traditional medicine for its antimicrobial, antiparasitic, and antinociceptive activities; also, it is a strong candidate as an anti-infammatory and a wound-healing agent [13–18]. Several compounds extracted from EOs have been reported to have antimicrobial activity. For example, cit- ronellol, estragole, eudesmol, eugenol, geraniol, linoleic acid, and phytol have all shown signifcant antimicrobial activities against human and plant pathogens [19–24]. Following our program of investigation with the purpose of exploring new alternatives for antimicrobial activities based on EOs, we evaluated the antimicrobial activities of the EOs extracted from allspice (PD), and rosemary (RO) against a panel of pathogenic bacteria and fungi. Te bacterial Hindawi BioMed Research International Volume 2019, Article ID 1639726, 8 pages https://doi.org/10.1155/2019/1639726