Antioxidant properties of coriander essential oil and linalool and their potential to control Campylobacter spp. Andreia Duarte a , ^ Angelo Luís a ,M  onica Oleastro b , Fernanda C. Domingues a, * a CICS-UBI e Health Sciences Research Centre, University of Beira Interior, Avenida Infante D. Henrique, 6200-506 Covilh~ a, Portugal b National Reference Laboratory for Gastrointestinal Infections, Department of Infectious Diseases, National Institute of Health Dr. Ricardo Jorge, Av. Padre Cruz, 1649-016 Lisbon, Portugal article info Article history: Received 25 July 2015 Received in revised form 23 September 2015 Accepted 24 September 2015 Available online 28 September 2015 Keywords: Coriander essential oil Linalool Anti-Campylobacter Anti-biofilm Quorum-sensing Antioxidant abstract Foodborne diseases remain common around the world with Campylobacteriosis being the most commonly reported zoonosis in the European Union in 2013. Campylobacter jejuni and Campylobacter coli are the main species associated with human illness. Furthermore, Campylobacter can develop biofilms which is becoming a major problem within the food industry. In addition to foodborne pathogens, oxidation is a non-microbial cause of deterioration of food causing loss of quality and safety. Thus, there is an urgent need in the food industry for new and effective strategies that can help prevent food contamination, spoilage and consequently, foodborne illnesses. Essential oils are known for their anti- microbial and antioxidant properties and are already widely used in the food industry. So, the aim of this work was to study the antimicrobial and anti-biofilm activity of coriander essential oil and its major compound linalool against C. jejuni and C. coli strains, as well as their effect in the quorum sensing (QS) system and their potential as antioxidants. Our results, demonstrated that both compounds have anti- Campylobacter activity, inhibited in vitro biofilm formation and promoted biofilm dispersion even at sub- MIC concentrations and interfered with the QS system through the inhibition of violacein production. Moreover, the essential oil and linalool were shown to have radical scavenging properties and lipid peroxidation inhibition ability which could make them potential alternatives to synthetic antioxidants. In sum, our results demonstrated the antibacterial, anti-biofilm, anti-QS and antioxidant potentials of the coriander essential oil and its major compound, linalool, suggesting that they could be used in the food industry to enhance shelf life of food products and increase food safety without requiring chemical additives or preservatives. © 2015 Elsevier Ltd. All rights reserved. 1. Introduction Despite advances in food safety, foodborne diseases remain common throughout the world and a growing threat to global public health. The ingestion and/or contact with contaminated food are the major cause of foodborne illness (CDC, 2015; EFSA & ECDC, 2015). Salmonella, Escherichia coli and Campylobacter are the three major pathogens that cause foodborne illnesses in United States (CDC, 2015), while Campylobacteriosis was the most commonly reported zoonosis in the European Union in 2013 (EFSA & ECDC, 2015). Campylobacteriosis is usually associated to the consump- tion of undercooked meat, environmental contamination, and cross-contamination between raw and cooked food (Hardy, Lackey, Cannon, Price, & Silbergeld, 2011; Silva, Leite, Fernandes, Mena, Gibbs, & Teixeira, 2011). Poultry is considered to be the main source of food-related human campylobacteriosis (Corry & Atabay, 2001; EFSA & ECDC, 2015). The most common species of Campylobacter associated with human illness are Campylobacter jejuni and Campylobacter coli (Fitzgerald, 2015). In addition, it has also been described that Campylobacter could develop biofilms that are more resistant to disinfectants and thus becoming a major problem within the food industry (Gunther & Chen, 2009; Srey, Jahid, & Ha, 2013). Quorum sensing (QS) communication is asso- ciated to the bacterial biofilm formation and antibiotic resistance, as well as to the bacterial proliferation in foods and food spoilage, therefore, QS inhibition could be a good strategy to control Campylobacter and to ensure food safety (Alvarez, Moreira, & Ponce, 2012; G€ olz, Sharbati, Backert, & Alter, 2012; Nazzaro, Fratianni, & * Corresponding author. E-mail address: fdomingues@ubi.pt (F.C. Domingues). Contents lists available at ScienceDirect Food Control journal homepage: www.elsevier.com/locate/foodcont http://dx.doi.org/10.1016/j.foodcont.2015.09.033 0956-7135/© 2015 Elsevier Ltd. All rights reserved. Food Control 61 (2016) 115e122