Atividade antibacteriana de óleos essenciais de Origanum vulgare (orégano) e Ocimum basilicum (manjericão) e sua aplicação em massa para embutido cárneo Antimicrobial activity of essential oils of Origanum vulgare (oregano) and Ocimum basilicum (basil) and its application in meat sausage

Species of the Vibrio genus are commonly reported as agents of food poisoning outbreaks associated with fish consumption. The objective of this study was to assess the antimicrobial activity of the essential oils of Origanum vulgare and Ocimum basilicum against Vibrio parahaemolyticus and Vibrio vulnificus, as well as to assess their addition to fillets of Mugil platanus and sensorial acceptance among consumers. The antimicrobial activity was analyzed by the disc diffusion test and minimal bactericidal concentration (MBC). M. platanus fillets, experimentally contaminated, were marinated for 24 hours in a solution containing 1.0% and 1.5% of essential oil of O. vulgare. For the sensory analysis, samples marinated in 1.5% of O. vulgare oil were prepared and offered to 100 testers. The oil of O. basilicum shows no antimicrobial activity, so its application would be ineffective; for such reason the subsequent tests were not performed. However, the essential oil of O. vulgare produced inhibition halo diameters ranging from 24.6 to 34.1 mm, on average, and the MBC ranging from 3.9% to 15.6%. When added to the product, the essential oil of O. vulgare eliminated the microorganisms that were experimentally inoculated. In the sensorial analysis, samples marinated in 1.5% of O. vulgare essential oil obtained an average of 6.82 of acceptance note among consumers.

The genus Staphylococcus spp. includes bacterial species that are opportunistic pathogens of humans and domestic animals as well. These microorganisms are commonly found on the skin and nasal cavities (Bannerman, 2003). These microorganisms are involved in several cases of food poisoning since some strains produce enterotoxins (Hasan, Hassawi, Al-Daghistani, & Hawari, 2014; Nitzsche, Zweifel, & Stephan, 2007). These enterotoxins are heat resistant. Therefore, once preformed are not eliminated during the thermal processing of food (Carmo et al., 2002) such as pasteurization of milk. Staphylococcal enterotoxins are detectable in food when Staphylococcus aureus counts are above 10 5 CFU/ml or

Surtos de doenças causadas por micro-organismos patogênicos em alimentos têm sido reportados com frequência, o que acaba sendo uma preocupação, tanto para consumidores quanto para a indústria. Os peixes são muito suscetíveis à infecção bacteriana e à deterioração microbiana, sendo, por isso, uma das fontes de transmissão de doenças pelos alimentos. Espécies do gênero Vibrio são comumente reportadas como agentes causadores de surtos alimentares associados ao consumo de peixes, sendo relatados surtos de vibriose com maior frequência e amplamente distribuídos pelo Mundo. Como possível alternativa natural para segurança microbiológica de alimentos, os óleos essenciais, que são constituídos por metabólitos secundários de plantas, vêm sendo aplicados na conservação de alimentos, por serem considerados mais seguros em relação aos aditivos químicos e por serem bem aceitos pelos consumidores. O objetivo desta revisão é fazer um parecer sobre casos de vibriose e sintetizar o conhecimento referente ao uso de óleos essenciais com potencial ação antimicrobiana perante espécies de Vibrio. Ainda são escassos os conhecimentos sobre os efeitos dos diferentes tipos de óleos essenciais já estudados sobre as espécies de Vibrio, sendo necessários mais estudos para o melhor entendimento dos efeitos de cada tipo de óleo para cada espécie de bactéria do gênero Vibrio.    Palavras-chave: Aditivos Naturais. Pescados. DTA   Abstract Outbreaks of diseases caused by pathogenic microorganisms in food have been reported frequently, which ends up being a concern for both consumers and the industry. Fish are very susceptible to bacterial infection and microbial deterioration and are therefore one of the sources of foodborne disease transmission. Species of the genus Vibrio are commonly reported as causative  food outbreaks agents associated with fish consumption, and outbreaks of vibriosis being reported more frequently and widely distributed around the world. As a possible natural alternative for microbiological food safety, essential oils, which are made up of secondary plant metabolites, have been applied in food preservation, as they are considered safer concerning chemical additives and because they are well accepted by consumers. The purpose of this review is to provide an opinion on cases of vibriosis and synthesize the knowledge regarding the use of essential oils with potential antimicrobial action against Vibrio species. Knowledge about the effects of the different types of essential oils already studied on Vibrio species is still scarce, and further studies are needed to better understand the effects of each type of oil for each bacterium species of the Vibrio genus.   Keywords: Natural Additives. Fish. Foodborne Illness.