CHEMICAL ENGINEERING TRANSACTIONS VOL. 75, 2019 A publication of The Italian Association of Chemical Engineering Online at www.cetjournal.it Guest Editors: Sauro Pierucci, Laura Piazza Copyright © 2019, AIDIC Servizi S.r.l. ISBN 978-88-95608-72-3; ISSN 2283-9216 Not Everything is a Question of Reputation: Safety of Bacteriocinogenic LAB Isolated from Smoked Salmon Svetoslav D. Todorov a,b,* , Elizabetta Tome c , Luis A. Nero a a Universidade Federal de Viçosa, Departamento de Veterinária, Campus UFV, 36570-900, Viçosa, MG, Brazil b Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, SP, Brazil c Instituto de Ciencia y Tecnología de Alimentos, Escuela de Biología, Universidad Central de Venezuela, Caracas, Venezuela slavi310570@abv.bg Total DNA extracted from bacteriocinogenic and potential probiotic lactic acid bacteria (LAB) (Lactobacillus curvatus ET06, ET30 and ET31, Lactobacillus fermentum ET35, Lactobacillus delbrueckii ET32, Pediococcus acidilactici ET34 and Enterococcus faecium ET05, ET12 and ET88), have been screened for presence of more than 50 genes related to production of biogenic amines (histidine decarboxylase, tyrosine decarboxylase and ornithine decarboxylase), virulence factors (sex pheromones, gelatinase, cytolisin, hyaluronidase, aggregation substance, enterococcal surface protein, endocarditis antigen, adhesion of collagen, integration factors) and antibiotic resistance (vancomycin, tetracycline, erythromycin, gentamicin, chloramphenicol, bacitracin). Tested strains presented low frequencies of presence for virulence genes. Only few genes were detected in some strains, indicating their safety for application in fermented food products. Besides all beneficial properties studied for various LAB, most considered as GRAS, a special attention need to be addressed on the possible presence of virulence factors, production of biogenic amines and antibiotic resistance. Results from appropriate biochemical tests and detected main genes associated to virulence factors and antibiotic resistance in LAB strains, could be considered as potential hazard of application of this organisms in food products. Moreover, additional in vitro and in vivo experiments must be designed in the system simulating GIT conditions in order to investigate deeper the possible expression of the present virulence genes. 1. Introduction Since establishing beneficial potential of lactic acid bacteria (LAB) in fermented products, intensive research in different aspects for application of these microorganisms, including investigation of probiotic potential, re- establish of the gastrointestinal (GIT) microbiota balance after antibiotics treatment, prevention and handling of Gastro-Intestinal Tract (GIT) disorders, stimulation of immune system, treatment of skin diseases, control of some pathogens, involvement in prevention of some type of cancer and role in oral health been carried (Martinez et al., 2012). However, despite a high numbers of studies were reported on beneficial properties of probiotic LAB, only a limited number of publications focus on the safety aspects of these strains. We can clearly state, that based on the fact that majority of the Lactobacillus spp. have well accepted Generally Recognized as Safe (GRAS) status and are considered as safe for human and other animal application based on their historical safety record and application in different fermented food products from plant, meat and dairy origin. However, scanning the existing literature can be scarily realized that some infection clinical cases were linked to some Lactobacillus spp. strains (Goldstein et al., 2015). One of the essential points in evaluation of safety of the future beneficial LAB is presence of antibiotic resistance. To have or to be free of antibiotic resistance genes is a very important question, when related to safety of LAB. From one point, probiotics frequently are applied as parallel treatment with antibiotics or in prevention of diseases. In these cases, resistance to antibiotics can be considered as only way of combined application of probiotics and antibiotics. However, from other point, if probiotic bacteria carries antibiotics resistance genes, especially on easy transferable genetic material, these can be a hazard of spread of these genes via horizontal genes transfer to DOI: 10.3303/CET1975076 Paper Received: 30 March 2018; Revised: 31 August 2018; Accepted: 23 January 2019 Please cite this article as: Todorov S., Tome E., Nero L., 2019, Not Everything is a Question of Reputation: Safety of Bacteriocinogenic Lab Isolated from Smoked Salmon, Chemical Engineering Transactions, 75, 451-456 DOI:10.3303/CET1975076 451