Antibacterial potential of essential oils against planktonic and sessile cells of Escherichia coli isolated from diarrhea cases in swine / Potencial antibacteriano de aceites esenciales contra células de Escherichia coli planctónicas y sésiles aisladas de diarrea porcina

Escherichia coli is a pathogen associated with infections in piglets in the post-weaning phase, its pathogenicity is related to the animal's susceptibility to bacterial enterotoxins. The objective of the present study was to determine the EOs activity against E. colistrain, in the form planktonic and sessile. Although the Disc-Diffusion tests to determine the Minimum Inhibitory Concentration, do not fully corroborate with the other analyzes of this study, it was noticed bacteria inhibition. The EOs were prepared at 0.4%, 0.8% and 1.0% for tests. The tested EOs were effective against E. coliplanktonic cells (p<0.05). As for the sessile cells, the most significant result was inhibition and 100% sessile cells at the concentration of 1.0% of Cymbopogon citratusEO. Although there was resistance in some treatments, the tested EOs demonstrated inhibition capacity, constituting promising alternatives for the control of E. coli, especially of planktonic cells.

Escherichia coli es un patógeno asociado con infecciones en lechones en la fase posterior al destete, su patogenicidad está relacionada con la susceptibilidad del animal a las enterotoxinas bacterianas. El objetivo del presente estudio fue determinar la actividad de contra E. coli, en la forma planctónico y sésil. Aunque las pruebas de difusión de disco para determinar la concentración inhibitoria mínima, no corroboran completamente con los otros análisis de este estudio, se observó inhibición de la bacteria. Las soluciones basadas en AE se prepararon al 0.4%, 0.8% y 1.0% para pruebas. Los AEs probados fueron efectivos contra las células planctónicas (p<0.05). En cuanto a las células sésiles, el resultado más significativo fue la inhibición y el 100% de las células sésiles a la concentración de 1,0% de Cymbopogon citratus. Aunque hubo resistencia en algunos tratamientos, los AEs probados demostraron capacidad de inhibición, constituyendo alternativas prometedoras para el control de E. coli, especialmente de células planctónicas.

Antimicrobial activity and chemical characterization of Laurel essential oil / Atividade antimicrobiana e caracterização química do óleo essencial de Louro / Actividad antimicrobiana y caracterización química del aceite esencial de Laurel

The factors that arouse interest in the study of essential oils as biocidal agents are numerous, such as the fact that they have antibacterial, antifungal, insecticidal, antioxidant, anti-inflammatory and larvicidal properties. The objective of this work was to evaluate the antimicrobial activity, in vitro, of the laurel (Laurus nobilis L) essential oil on the growth of pathogenic bacteria Salmonella enterica serovar Typhimurium ATCC 14028 and Staphylococcus aureus ATCC 25923, at different exposure times, as well as to perform the chemical characterization. Twenty compounds were identified and quantified, representing 96.57% of the total composition. The class of oxygenated monoterpenes represented the majority class of the essential oil, with 1,8-cineol (33.8%) as the substance found in greater quantity, followed by linalool (17.79%). The third constituent in greater quantity was sabinene (12.23%), belonging to the group of monoterpene hydrocarbons. Terpinyl acetate (9.41%) was also considered to be quantitatively representative. Laurel essential oil showed bacteriostatic activity against S. Typhimurium ATCC 14028 and S. aureus ATCC 25923.(AU)

Os fatores que despertam interesse no estudo dos óleos essenciais como agentes biocidas são inúmeros, como o fato de possuírem propriedades antibacteriana, antifúngica, inseticida, antioxidante, antiinflamatória e larvicida. O objetivo deste trabalho foi avaliar a atividade antimicrobiana, in vitro, do óleo essencial de louro (Laurus nobilis L) sobre o crescimento das bactérias patogênicas Salmonella enterica sorovar Typhimurium ATCC 14028 e Staphylococcus aureus ATCC 25923, em diferentes tempos de exposição, assim como realizar a caracterização química do óleo. Vinte compostos foram identificados e quantificados, representando 96,57% da composição total. A classe dos monoterpenos oxigenados representou a classe majoritária do óleo essencial, sendo o 1,8-cineol (33,8%) a substância encontrada em maior quantidade, seguido do linalol (17,79%). O terceiro constituinte em maior quantidade foi o sabineno (12,23%), pertencente ao grupo dos hidrocarbonetos monoterpênicos. O acetato de terpinila (9,41%) também foi considerado quantitativamente representativo. O óleo essencial de louro apresentou atividade bacteriostática contra S. Typhimurium ATCC 14028 e S. aureus ATCC 25923.(AU)

Los factores que despiertan interés en el estudio de los aceites esenciales como agentes biocidas son innumerables, como el hecho de que tienen propiedades antibacterianas, anti fúngicas, insecticidas, antioxidantes, antiinflamatorias y larvicidas. El objetivo de este trabajo ha sido evaluar la actividad antimicrobiana, in vitro, del aceite esencial de laurel (Laurus nobilis L) sobre el crecimiento de bacterias patógenas Salmonella enterica serovar Typhimurium ATCC 14028 y Staphylococcus aureus ATCC 25923, en diferentes momentos de exposición, así como realizar la caracterización química del aceite. Se identificaron y cuantificaron veinte compuestos, que representan el 96,57% de la composición total. La clase de mono terpenos oxigenados representó la clase principal de aceite esencial, siendo el 1,8-cineol (33,8%) la sustancia que se encuentra en mayor cantidad, seguida del linalol (17,79%). El tercer constituyente en mayor cantidad fue el sabineno (12,23%), perteneciente al grupo de los hidrocarburos monoterpénicos. El acetato de terpinilo (9,41%) también se consideró cuantitativamente representativo. El aceite esencial de laurel mostró actividad bacteriostática contra S. Typhimurium ATCC 14028 y S. aureus ATCC 25923.(AU)

Antibacterial and anti-biofilm activity of cinnamon essential oil and eugenol / Atividade antibacteriana e anti-biofilme de óleo essencial de canela e eugenol

Biofilms are responsible for most of the interference caused by microorganisms in food processing. The aim of this study was to evaluate the cinnamon (Cinnamomum zeylanicum) essential oil and eugenol sanitizer and anti-biofilm activity against biofilms. Concentrations used of essential oil were 0.0% (control) 0.12%; 0.48%; 0.96% and 1.92%; the amount of eugenol was 0.76%. Concentrations were determined from other published studies. Number of viable cells and quantification the bacterial biomass were determined. Anti-biofilm treatment was effective in preventing the formation of biofilms. The 1.92% concentration was the most satisfactorily with Escherichia coli reduction of 5.91log CFUcm-2 and Staphylococcus aureus reduction of 5.17log CFUcm-2 (P<0.05) biomass of the two bacteria. Sanitizing treatment was not effective in reducing biomass. Seen this, the cinnamon and eugenol essential oil may be promising alternatives for controlling biofilms.(AU)

Os biofilmes são responsáveis pela maior parte da interferência causada pelos micro-organismos no processamento de alimentos. O objetivo deste estudo foi avaliar a atividade anti-biofilme do óleo essencial de canela (Cinnamomum zeylanicum) e do composto majoritário eugenol. As concentrações utilizadas de óleo essencial foram de 0,0% (controle), 0,12%; 0,48%; 0,96% e 1,92%; a concentração de eugenol foi de 0,76%. As concentrações foram determinadas a partir de outros estudos publicados. Determinou-se o número de células viáveis e quantificou-se a biomassa bacteriana. O tratamento anti-biofilme foi eficaz na prevenção e formação de biofilmes. A concentração de 1,92% foi satisfatória, com redução de 5,91log CFUcm-2 de células viáveis em biofilme de Escherichia coli e redução de 5,17log CFU cm-2 de Staphylococcus aureus. A biomassa de ambas bactérias foi reduzida significativamente (P<0,05), entretanto, o tratamento sanitizante não foi eficaz na redução da biomassa. Diante dos resultados, o óleo essencial de canela e eugenol podem ser alternativas promissoras no controle de biofilmes.(AU)

Antibacterial and anti-biofilm activity of cinnamon essential oil and eugenol / Atividade antibacteriana e anti-biofilme de óleo essencial de canela e eugenol

ABSTRACT: Biofilms are responsible for most of the interference caused by microorganisms in food processing. The aim of this study was to evaluate the cinnamon (Cinnamomum zeylanicum) essential oil and eugenol sanitizer and anti-biofilm activity against biofilms. Concentrations used of essential oil were 0.0% (control) 0.12%; 0.48%; 0.96% and 1.92%; the amount of eugenol was 0.76%. Concentrations were determined from other published studies. Number of viable cells and quantification the bacterial biomass were determined. Anti-biofilm treatment was effective in preventing the formation of biofilms. The 1.92% concentration was the most satisfactorily with Escherichia coli reduction of 5.91log CFUcm-2 and Staphylococcus aureus reduction of 5.17log CFUcm-2 (P<0.05) biomass of the two bacteria. Sanitizing treatment was not effective in reducing biomass. Seen this, the cinnamon and eugenol essential oil may be promising alternatives for controlling biofilms.

RESUMO: Os biofilmes são responsáveis pela maior parte da interferência causada pelos micro-organismos no processamento de alimentos. O objetivo deste estudo foi avaliar a atividade anti-biofilme do óleo essencial de canela (Cinnamomum zeylanicum) e do composto majoritário eugenol. As concentrações utilizadas de óleo essencial foram de 0,0% (controle), 0,12%; 0,48%; 0,96% e 1,92%; a concentração de eugenol foi de 0,76%. As concentrações foram determinadas a partir de outros estudos publicados. Determinou-se o número de células viáveis e quantificou-se a biomassa bacteriana. O tratamento anti-biofilme foi eficaz na prevenção e formação de biofilmes. A concentração de 1,92% foi satisfatória, com redução de 5,91log CFUcm-2 de células viáveis em biofilme de Escherichia coli e redução de 5,17log CFU cm-2 de Staphylococcus aureus. A biomassa de ambas bactérias foi reduzida significativamente (P<0,05), entretanto, o tratamento sanitizante não foi eficaz na redução da biomassa. Diante dos resultados, o óleo essencial de canela e eugenol podem ser alternativas promissoras no controle de biofilmes.

Sensibilidade de bactérias patogênicas em alimentos a óleos essenciais de plantas medicinais e condimentares

Os óleos essenciais (OEs), também chamados de óleos voláteis ou etéreos, são produtos do metabolismo secundário dos vegetais. Tanto os óleos como os seus componentes são utilizados como produtos nas indústrias de alimentos, pois possuem comprovada atividade antimicrobiana. As Concentrações Mínimas Inibitórias (CMI) desses óleos para diversas bactérias devem ser determinadas. As CMI variam de acordo com o óleo utilizado, dos compostos majoritários e da fisiologia da bactéria em estudo. Neste trabalho, os OEs das plantas Melaleuca alternifolia, Cinnamomum zeylanicum e Cymbopogon martini foram testados quanto à atividade antimicrobiana (através da CMI) contra as bactérias patogênicas Escherichia coli e Staphylococcus aureus. Neste estudo, verificamos que E. coli e S. aureus foram sensíveis aos três OEs em todas as concentrações. Os resultados in vitro sugerem que os três OEs possuem potencial para utilização, como uma alternativa aos antimicrobianos e conservantes sintéticos.(AU)

Essential oils (EOs) also known as volatile or ethereal oils, are products of plants secondary metabolism. Both oils as their products are used as components in food industries, as they have proven antimicrobial activity. The Minimum Inhibitory Concentrations (MIC) of these oils for various bacteria must be determined. The MIC will vary depending on the oil used, the major compounds and physiology of the bacteria under study. In this work, the Melaleuca alternifolia plant EO, Cinnamomum zeylanicum and Cymbopogon martini were tested for antimicrobial activity (by MIC) against pathogenic bacteria Escherichia coli and Staphylococcus aureus. In this study, we found that E. coli and S. aureus were sensitive to the three EOs in all concentrations. In vitro results suggest that the three EOs are potentially useful as an alternative to synthetic preservatives and antimicrobials.(AU)

Reduction of Aeromonas hidrophyla biofilm on stainless stell surface by essential oils.

This study demonstrates the possibility of using sanitizing detergents based on natural products for the elimination and/or reduction of Aeromonas hydrophila biofilm formed on stainless steel surfaces. The goal of this work was to determine the reduction effect of sanitizing detergents containing essential oils of Thymus vulgaris (thyme) and Cymbopogon citratus (lemongrass) on biofilm formed by A. hydrophila on AISI 304 stainless steel coupons, using UHT skimmed milk as substratum. There was adhesion and biofilm formation by A. hydrophila at 28 °C, presenting 7.60 log cfu.cm(-2) after the fourth day of cultivation. There was no significant difference between the lemongrass treatment and that of the thyme oil (p < 0.05). However, both treatments significantly reduced the biofilm, differing significantly from the NaOH control (p > 0.05). The treatment with lemongrass solution reduced the biofilm by 4.51 log cfu cm(-2) at 25 °C. The thyme detergent also reduced the number of cfu cm(-2) by 3.84 log cycles at 25 °C. The use of the lemongrass and thyme solutions efficiently reduced the A. hydrophila biofilm.

Reduction of Aeromonas hidrophyla biofilm on stainless stell surface by essential oils

This study demonstrates the possibility of using sanitizing detergents based on natural products for the elimination and/or reduction of Aeromonas hydrophila biofilm formed on stainless steel surfaces. The goal of this work was to determine the reduction effect of sanitizing detergents containing essential oils of Thymus vulgaris (thyme) and Cymbopogon citratus (lemongrass) on biofilm formed by A. hydrophila on AISI 304 stainless steel coupons, using UHT skimmed milk as substratum. There was adhesion and biofilm formation by A. hydrophila at 28 ºC, presenting 7.60 log cfu.cm-2 after the fourth day of cultivation. There was no significant difference between the lemongrass treatment and that of the thyme oil (p < 0.05). However, both treatments significantly reduced the biofilm, differing significantly from the NaOH control (p > 0.05). The treatment with lemongrass solution reduced the biofilm by 4.51 log cfu cm-2 at 25 ºC. The thyme detergent also reduced the number of cfu cm-2 by 3.84 log cycles at 25 ºC. The use of the lemongrass and thyme solutions efficiently reduced the A. hydrophila biofilm.(AU)

Reduction of Aeromonas hidrophyla biofilm on stainless stell surface by essential oils

This study demonstrates the possibility of using sanitizing detergents based on natural products for the elimination and/or reduction of Aeromonas hydrophila biofilm formed on stainless steel surfaces. The goal of this work was to determine the reduction effect of sanitizing detergents containing essential oils of Thymus vulgaris (thyme) and Cymbopogon citratus (lemongrass) on biofilm formed by A. hydrophila on AISI 304 stainless steel coupons, using UHT skimmed milk as substratum. There was adhesion and biofilm formation by A. hydrophila at 28 ºC, presenting 7.60 log cfu.cm-2 after the fourth day of cultivation. There was no significant difference between the lemongrass treatment and that of the thyme oil (p < 0.05). However, both treatments significantly reduced the biofilm, differing significantly from the NaOH control (p > 0.05). The treatment with lemongrass solution reduced the biofilm by 4.51 log cfu cm-2 at 25 ºC. The thyme detergent also reduced the number of cfu cm-2 by 3.84 log cycles at 25 ºC. The use of the lemongrass and thyme solutions efficiently reduced the A. hydrophila biofilm.

Microbiological quality of the hands of food handlers and of the sanitizer in the meat processing industry / Qualidade microbiológica das mãos de manipuladores de alimentos e da sanitizante na indústria de carne

The hygienic-sanitary quality of foods constitutes an essential factor for consumer food safety. Food is increasingly exposed to a series of dangers and opportunities for contamination by microorganisms due to inadequate handling practices during food processing. Most of the people involved with the handling of foods lack knowledge related to hygienic-sanitary care that should be taken. With the objective of verifying the microbiota of the handlers? hands in a meat industry, the microbiological monitoring was conducted before and after the sanitation of the hands. The collections were conducted in the deboning and cold cut sectors, with 20% participation of the handlers in each sector. There was presence of thermotolerant coliforms, total coliforms and Staphylococcus aureus before and after the sanitation of hands in the deboning sector. In the cold cut sector, the presence of thermotolerant coliforms was only verified before the sanitation, however the total coliform group was detected before and after sanitation. There was no presence of S. aureus. There was no presence of Salmonella spp in any of the analyzed samples.

A qualidade higiênico-sanitária dos alimentos constitui um fator essencial à segurança alimentar dos consumidores. Os alimentos estão cada vez mais expostos a uma série de perigos e oportunidades de contaminações por microrganismos, devido às práticas inadequadas de manipulação no processamento dos alimentos. A maioria das pessoas envolvidas com a manipulação de alimentos carece de conhecimentos relativos aos cuidados higiênico-sanitários que devem ser seguidos. Com o objetivo de verificar a microbiota das mãos de manipuladores em uma indústria de carnes, foi realizado o monitoramento microbiológico antes e após a higienização das mãos. As coletas foram realizadas nos setores da desossa e dos embutidos, com a participação de 20% dos manipuladores de cada setor. Na desossa, houve presença de coliformes termotolerantes, coliformes totais e Staphylococcus aureus antes e após a higienização das mãos. No setor dos embutidos, verificou-se a presença de coliformes termotolerantes somente antes da higienização, porém o grupo dos coliformes totais foi detectado antes e após a higienização, não houve presença de S. aureus. Em nenhuma das amostras analisadas ocorreu presença de Salmonella spp.