Antimicrobial and toxicological evaluation of Origanum vulgare: an in vivo study / Avaliação antimicrobiana e toxicológica de Origanum vulgare: um estudo in vivo

Origanum vulgare has been of great interest in academia and pharma industry due to its antioxidant, antifungal and antitumor properties. The present study aimed to find the anti-MRSA potential and in vivo toxicity assessments of O. vulgare. O. vulgare extract was used to monitor anti-MRSA activity in mice. Following MRSA established infection in mice (Mus musculus), treatment with O. vulgare was continued for 7 days. Autopsies were performed and re-isolation, gross lesion scoring and bacterial load in various organs were measured. Additionally, blood sample was analysed for hematological assays. Toxicity assessment of O. vulgare potential as medicine was done at 200 mg/kg and 400 mg/kg by evaluating liver and kidney functions. Bacterial load and gross lesion in lungs and heart were significantly low compared to positive control following O. vulgare treatment. Likewise, O. vulgare treated groups had hematological, neutrophil and TLC values similar to control groups. Increased AST, ALP and total bilirubin along with marked hepatocellular degeneration and distortion around the central vein, inflammatory cell infiltration, and cytoplasmic vacuolization of hepatic cells was observed at higher dose. It is concluded that crude extract of O. vulgare may contain beneficial secondary metabolites and in future may be explored for curing infectious diseases.

Origanum vulgare tem despertado grande interesse na academia e na indústria farmacêutica devido às suas propriedades antioxidantes, antifúngicas e antitumorais. O presente estudo teve como objetivo encontrar o potencial anti-MRSA e avaliações de toxicidade in vivo de O. vulgare. O extrato de O. vulgare foi usado para monitorar a atividade anti-MRSA em camundongos. Após infecção estabelecida por MRSA em camundongos (Mus musculus), o tratamento com O. vulgare foi continuado por 7 dias. As autópsias foram realizadas e o reisolamento, pontuação das lesões grosseiras e carga bacteriana em vários órgãos foram medidos. Além disso, a amostra de sangue foi analisada para ensaios hematológicos. A avaliação da toxicidade do potencial de O. vulgare como medicamento foi feita com 200 mg / kg e 400 mg / kg, avaliando as funções hepática e renal. A carga bacteriana e as lesões graves nos pulmões e no coração foram significativamente baixas em comparação com o controle positivo após o tratamento com O. vulgare. Da mesma forma, os grupos tratados com O. vulgare apresentaram valores hematológicos, de neutrófilos e de TLC semelhantes aos grupos de controle. Aumento de AST, ALP e bilirrubina total juntamente com degeneração hepatocelular marcada e distorção ao redor da veia central, infiltração de células inflamatórias e vacuolização citoplasmática de células hepáticas foram observados em doses mais altas. Conclui-se que o extrato bruto de O. vulgare pode conter metabólitos secundários benéficos e, no futuro, pode ser explorado para a cura de doenças infecciosas.

Antimicrobial and toxicological evaluation of Origanum vulgare: an in vivo study / Avaliação antimicrobiana e toxicológica de Origanum vulgare: um estudo in vivo

Origanum vulgare has been of great interest in academia and pharma industry due to its antioxidant, antifungal and antitumor properties. The present study aimed to find the anti-MRSA potential and in vivo toxicity assessments of O. vulgare. O. vulgare extract was used to monitor anti-MRSA activity in mice. Following MRSA established infection in mice (Mus musculus), treatment with O. vulgare was continued for 7 days. Autopsies were performed and re-isolation, gross lesion scoring and bacterial load in various organs were measured. Additionally, blood sample was analysed for hematological assays. Toxicity assessment of O. vulgare potential as medicine was done at 200 mg/kg and 400 mg/kg by evaluating liver and kidney functions. Bacterial load and gross lesion in lungs and heart were significantly low compared to positive control following O. vulgare treatment. Likewise, O. vulgare treated groups had hematological, neutrophil and TLC values similar to control groups. Increased AST, ALP and total bilirubin along with marked hepatocellular degeneration and distortion around the central vein, inflammatory cell infiltration, and cytoplasmic vacuolization of hepatic cells was observed at higher dose. It is concluded that crude extract of O. vulgare may contain beneficial secondary metabolites and in future may be explored for curing infectious diseases.(AU)

Origanum vulgare tem despertado grande interesse na academia e na indústria farmacêutica devido às suas propriedades antioxidantes, antifúngicas e antitumorais. O presente estudo teve como objetivo encontrar o potencial anti-MRSA e avaliações de toxicidade in vivo de O. vulgare. O extrato de O. vulgare foi usado para monitorar a atividade anti-MRSA em camundongos. Após infecção estabelecida por MRSA em camundongos (Mus musculus), o tratamento com O. vulgare foi continuado por 7 dias. As autópsias foram realizadas e o reisolamento, pontuação das lesões grosseiras e carga bacteriana em vários órgãos foram medidos. Além disso, a amostra de sangue foi analisada para ensaios hematológicos. A avaliação da toxicidade do potencial de O. vulgare como medicamento foi feita com 200 mg / kg e 400 mg / kg, avaliando as funções hepática e renal. A carga bacteriana e as lesões graves nos pulmões e no coração foram significativamente baixas em comparação com o controle positivo após o tratamento com O. vulgare. Da mesma forma, os grupos tratados com O. vulgare apresentaram valores hematológicos, de neutrófilos e de TLC semelhantes aos grupos de controle. Aumento de AST, ALP e bilirrubina total juntamente com degeneração hepatocelular marcada e distorção ao redor da veia central, infiltração de células inflamatórias e vacuolização citoplasmática de células hepáticas foram observados em doses mais altas. Conclui-se que o extrato bruto de O. vulgare pode conter metabólitos secundários benéficos e, no futuro, pode ser explorado para a cura de doenças infecciosas.(AU)

Pre- and postnatal evaluation of offspring rats exposed to Origanum vulgare essential oil during mating, gestation and lactation / Avaliação pré e pós-natal da prole de ratos expostos ao óleo essencial de Origanum vulgare durante acasalamento, gestação e lactação

Despite the increasing use of oregano (Origanum vulgare L.) essential oil for therapeutic purposes, pre- and postnatal development of animals offspring exposed to this oil has not yet been evaluated. In line with previous concerns of genotoxicity, in this study adult rats were exposed to different doses of oregano essential oil (3, 9 and 27% vol/vol) during pre-mating, mating, gestation and lactation. Prenatal screening included fetal development and uterine inspection, where the reproductive rate of females such as breeding, pregnancy, delivery, viability and post-implantation loss rate were measured. Postnatal evaluation of rat offspring included motor development, neuroendocrine and behavioral assessment. Body weight of rat dams and signs of dystocia were evaluated daily. Development of physic characteristics and reflex tests of puppies were also assessed. Additionally, these rats, when adults, were submitted to sexual and open field behavioral tests. The main differences among the groups were observed in the indices of mating, pregnancy and post-implantation loss (P < 0.01). Results demonstrated that the treatment of parental generation with oregano essential oil has the potential to affect the developing fetuses at the highest dose used, but without causing maternal toxicity and changes in general behavior and development of the progeny.

Apesar do aumento do uso do óleo essencial de orégano (Origanum vulgare L.) para fins terapêuticos, o desenvolvimento pré e pós-natal da progênie de animais expostos a este óleo ainda não foi avaliado. Partindo das suspeitas prévias de genotoxicidade desse óleo, neste estudo, ratos Wistar adultos foram expostos a diferentes doses do óleo essencial de orégano (3, 9 e 27% vol/vol) durante o acasalamento, a gestação e a lactação. Para a avaliação pré-natal, o desenvolvimento gestacional foi observado e os úteros inspecionados, assim como os índices reprodutivos das fêmeas, como a taxa de acasalamento, de gestação, parto e perdas pós-implantação. Na avaliação pós-natal, observou-se o desenvolvimento motor, neuroendócrino e comportamental da prole. Observou-se, diariamente, o peso das ratas e sinais de distocia. Após o parto, as características de desenvolvimento e testes de reflexos dos filhotes foram avaliadas, enquanto que, na puberdade, foram realizadas análises histopatológicas e dosagem hormonal. Adicionalmente, na idade adulta, esses ratos foram submetidos ao teste de comportamento em campo aberto e ao comportamento sexual. As principais diferenças entre os grupos foram nos índices de acasalamento, de gestação e de perdas pós-implantação (P < 0,01). Os resultados demonstram que o tratamento da geração parental com óleo essencial de orégano tem potencial para afetar os índices reprodutivos das ratas e o desenvolvimento dos fetos na maior dose utilizada, mas sem causar toxicidade materna e alterações no desenvolvimento geral e comportamental da sua progênie.

Anti-equine arteritis virus activity of ethanolic extract and compounds from Origanum vulgare / Atividade do extrato etanólico e compostos de Origanum vulgare contra o virus da arterite equina

The equine arteritis virus (EAV) is responsible by an important respiratory and reproductive disease in equine populations and there is no specific antiviral treatment available. The objective of this study was to investigate the activity of an ethanolic crude extract of Origanum vulgare (EEO) and of isolated compound caffeic acid, p-coumaric acid, rosmarinic acid, quercetin, luteolin, carnosol, carnosic acid, kaempferol and apigenin against EAV. The assays were performed using non-cytotoxic concentrations. The antiviral activity was monitored initially by cytopathic effect inhibition (CPE) assay in RK13 cells in the presence or absence of EEO. Pre-incubated cells with EEO were also examined to show prophylactic effect. Direct viral inactivation by EEO and isolated compounds was evaluated by incubation at 37C or 20C. After the incubation period, the infectivity was immediately determined by virus titrations on cell cultures and expressed as 50% tissue culture infective dose (TCID50)/100 µL. There was significant virucidal activity of EEO and of the compounds caffeic acid, p-coumaric acid, quercetin, carnosic acid and kaempferol. When EEO was added after infection, EEO inhibited the virus growth in infected cells, as evidenced by significant reduction of the viral titre. The results provide evidence that the EEO exhibit an inhibitory effect anti-EAV. Among the main compounds evaluated, caffeic acid, p-coumaric acid,carnosic acid, kaempferol and mainly quercetin, contributed to the activity of EEO. EEO may represent a good prototype for the development of a new antiviral agent, presenting promising for combating arteriviruses infections.(AU)

O virus da arterite equine (EAV) é responsável por uma importante doença respiratória e reprodutiva na população de equinos e não há tratamento antiviral específico disponível. O objetivo desse estudo foi investigar a atividade de um extrato etanólico de Origanum vulgare (EEO) e dos compostos isolados ácido caféico, ácido p-cumarico, ácido rosmarínico, quercetina, luteolina, carnosol, ácido carnósico, campferol e apigenina contra o EAV. Os ensaios foram realizados com concentrações não citotóxicas. A atividade antiviral foi monitorada inicialmente por um ensaio de inibição de efeito citopático (CPE) em células RK13 na presença ou ausência do EEO. Células pré-incubadas com o EEO foram também examinadas para a presença de efeito profilático. Inativação direta do EAV pelo EEO e pelos compostos isolados foi avaliada mediante incubação a 37C ou 20C. Após o período de incubação, a infectividade foi imediatamente determinada por titulação viral em cultivo celular sendo expresso como dose infectiva a 50% (TCID50)/100 µL. Houve significativa atividade virucida do EEO e dos compostos ácido caféico, ácido p-cumarico, quercetina, ácido carnósico e campferol. Quando o EEO foi adicionado após a infecção, o EEO inibiu a replicação do vírus nas células infectadas, o que foi evidenciado pela redução significativa do título viral. Os resultados fornecem evidências de que o EEO possui efeito anti-EAV.Entre os principais compostos presentes avaliados, ácido caféico, ácido p-cumarico, ácido carnósico, campferol e, principalmente, quercetina, contribuíram para a atividade antiviral do extrato. O EEO pode representar um bom protótipo para o desenvolvimento de um novo agente antiviral, sendo promissor para combater infecções por arterivírus.(AU)

Pre- and postnatal evaluation of offspring rats exposed to Origanum vulgare essential oil during mating, gestation and lactation / Avaliação pré e pós-natal da prole de ratos expostos ao óleo essencial de Origanum vulgare durante acasalamento, gestação e lactação

Despite the increasing use of oregano (Origanum vulgare L.) essential oil for therapeutic purposes, pre- and postnatal development of animals offspring exposed to this oil has not yet been evaluated. In line with previous concerns of genotoxicity, in this study adult rats were exposed to different doses of oregano essential oil (3, 9 and 27% vol/vol) during pre-mating, mating, gestation and lactation. Prenatal screening included fetal development and uterine inspection, where the reproductive rate of females such as breeding, pregnancy, delivery, viability and post-implantation loss rate were measured. Postnatal evaluation of rat offspring included motor development, neuroendocrine and behavioral assessment. Body weight of rat dams and signs of dystocia were evaluated daily. Development of physic characteristics and reflex tests of puppies were also assessed. Additionally, these rats, when adults, were submitted to sexual and open field behavioral tests. The main differences among the groups were observed in the indices of mating, pregnancy and post-implantation loss (P < 0.01). Results demonstrated that the treatment of parental generation with oregano essential oil has the potential to affect the developing fetuses at the highest dose used, but without causing maternal toxicity and changes in general behavior and development of the progeny.(AU)

Apesar do aumento do uso do óleo essencial de orégano (Origanum vulgare L.) para fins terapêuticos, o desenvolvimento pré e pós-natal da progênie de animais expostos a este óleo ainda não foi avaliado. Partindo das suspeitas prévias de genotoxicidade desse óleo, neste estudo, ratos Wistar adultos foram expostos a diferentes doses do óleo essencial de orégano (3, 9 e 27% vol/vol) durante o acasalamento, a gestação e a lactação. Para a avaliação pré-natal, o desenvolvimento gestacional foi observado e os úteros inspecionados, assim como os índices reprodutivos das fêmeas, como a taxa de acasalamento, de gestação, parto e perdas pós-implantação. Na avaliação pós-natal, observou-se o desenvolvimento motor, neuroendócrino e comportamental da prole. Observou-se, diariamente, o peso das ratas e sinais de distocia. Após o parto, as características de desenvolvimento e testes de reflexos dos filhotes foram avaliadas, enquanto que, na puberdade, foram realizadas análises histopatológicas e dosagem hormonal. Adicionalmente, na idade adulta, esses ratos foram submetidos ao teste de comportamento em campo aberto e ao comportamento sexual. As principais diferenças entre os grupos foram nos índices de acasalamento, de gestação e de perdas pós-implantação (P < 0,01). Os resultados demonstram que o tratamento da geração parental com óleo essencial de orégano tem potencial para afetar os índices reprodutivos das ratas e o desenvolvimento dos fetos na maior dose utilizada, mas sem causar toxicidade materna e alterações no desenvolvimento geral e comportamental da sua progênie.(AU)

Cytotoxicity and anti-Sporothrix brasiliensis activity of the Origanum majorana Linn. oil

The study aimed to evaluate the anti-Sporothrix sp. activity of the essential oil of Origanum majorana Linn. (marjoram), its chemical analysis, and its cytotoxic activity. A total of 18 fungal isolates of Sporothrix brasiliensis (n: 17) from humans, dogs and cats, and a standard strain of Sporothrix schenckii (n: 1) were tested using the broth microdilution technique (Clinical and Laboratory Standard Institute - CLSI M27-A3) and the results were expressed in minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC). The MIC50 and MIC90 of itraconazole against S. brasiliensis were 2 µg/mL and 8 µg/mL, respectively, and the MFC50 and MFC90 were 2 µg/mL and >16 µg/mL, respectively, with three S. brasiliensis isolates resistant to antifungal. S. schenckii was sensitive at MIC of 1 µg/mL and MFC of 8 µg/mL. For the oil of O. majorana L., all isolates were susceptible to MIC of 2.25-9 mg/mL and MFC of 2.25-18 mg/mL. The MIC50 and MIC90 were 2.25 mg/mL and 4.5 mg/mL, respectively, and the MFC50/90 values were twice more than the MIC. Twenty-two compounds were identified by gas chromatography with a flame ionization detector (CG-FID) and 1,8-cineole and 4-terpineol were the majority. Through the colorimetric (MTT) assay, the toxicity was observed in 70-80% of VERO cells between 0.078 and 5 mg/mL. For the first time, the study demonstrated the satisfactory in vitro anti-Sporothrix sp. activity of marjoram oil and further studies are needed to ensure its safe and effective use.(AU)

Reproductive toxicity assessment of Origanum vulgare essential oil on male Wistar rats

Background: The oregano essential oil (Origanum vulgare L.) is rich in phenolic compounds with therapeutic actionssuch as antimicrobial, antifungal and antioxidant. Based on the therapeutic potential and clinical use of oregano essentialoil, in vivo toxicology studies of oregano essential oil are scarce and the current researches focus on the genotoxicity ofseveral species of oregano; however, toxicological and complementary studies are needed to ensure safety of formulationscontaining this oil. Through values of Minimum Inhibitory Concentration (MIC) of oregano essential oil against Candidaspecies, and increased in an exponential scale, the initial dose was obtained. This study aims to evaluate male fertilitythrough the reproductive aspects of rats chronically treated with oregano essential oil.Materials, Methods & Results: The rats were divided into five groups with 10 males and 30 females each; three groupswere treated with oregano essential oil at a concentration of 3% Vol/Vol (GO3%), of 9% Vol/Vol (GO9%) and of 27% Vol/Vol (GO27%). The negative control group received the vehicle, 0.001% Vol/Vol Tween 80 (GC-) and the positive controlgroup was treated with thymol and terpinen-4-ol, at the same concentration found in the oregano essential oil, detected bygas chromatography (3% + 3% Vol/Vol) (GC+). Animals were allowed to adapt for at least ten days before the beginningof the experiment. They were maintained under...(AU)

Reproductive toxicity assessment of Origanum vulgare essential oil on male Wistar rats

Background: The oregano essential oil (Origanum vulgare L.) is rich in phenolic compounds with therapeutic actionssuch as antimicrobial, antifungal and antioxidant. Based on the therapeutic potential and clinical use of oregano essentialoil, in vivo toxicology studies of oregano essential oil are scarce and the current researches focus on the genotoxicity ofseveral species of oregano; however, toxicological and complementary studies are needed to ensure safety of formulationscontaining this oil. Through values of Minimum Inhibitory Concentration (MIC) of oregano essential oil against Candidaspecies, and increased in an exponential scale, the initial dose was obtained. This study aims to evaluate male fertilitythrough the reproductive aspects of rats chronically treated with oregano essential oil.Materials, Methods & Results: The rats were divided into five groups with 10 males and 30 females each; three groupswere treated with oregano essential oil at a concentration of 3% Vol/Vol (GO3%), of 9% Vol/Vol (GO9%) and of 27% Vol/Vol (GO27%). The negative control group received the vehicle, 0.001% Vol/Vol Tween 80 (GC-) and the positive controlgroup was treated with thymol and terpinen-4-ol, at the same concentration found in the oregano essential oil, detected bygas chromatography (3% + 3% Vol/Vol) (GC+). Animals were allowed to adapt for at least ten days before the beginningof the experiment. They were maintained under...

Anti-equine arteritis virus activity of ethanolic extract and compounds from Origanum vulgare / Atividade do extrato etanólico e compostos de Origanum vulgare contra o virus da arterite equina

The equine arteritis virus (EAV) is responsible by an important respiratory and reproductive disease in equine populations and there is no specific antiviral treatment available. The objective of this study was to investigate the activity of an ethanolic crude extract of Origanum vulgare (EEO) and of isolated compound caffeic acid, p-coumaric acid, rosmarinic acid, quercetin, luteolin, carnosol, carnosic acid, kaempferol and apigenin against EAV. The assays were performed using non-cytotoxic concentrations. The antiviral activity was monitored initially by cytopathic effect inhibition (CPE) assay in RK13 cells in the presence or absence of EEO. Pre-incubated cells with EEO were also examined to show prophylactic effect. Direct viral inactivation by EEO and isolated compounds was evaluated by incubation at 37C or 20C. After the incubation period, the infectivity was immediately determined by virus titrations on cell cultures and expressed as 50% tissue culture infective dose (TCID50)/100 µL. There was significant virucidal activity of EEO and of the compounds caffeic acid, p-coumaric acid, quercetin, carnosic acid and kaempferol. When EEO was added after infection, EEO inhibited the virus growth in infected cells, as evidenced by significant reduction of the viral titre. The results provide evidence that the EEO exhibit an inhibitory effect anti-EAV. Among the main compounds evaluated, caffeic acid, p-coumaric acid,carnosic acid, kaempferol and mainly quercetin, contributed to the activity of EEO. EEO may represent a good prototype for the development of a new antiviral agent, presenting promising for combating arteriviruses infections.

O virus da arterite equine (EAV) é responsável por uma importante doença respiratória e reprodutiva na população de equinos e não há tratamento antiviral específico disponível. O objetivo desse estudo foi investigar a atividade de um extrato etanólico de Origanum vulgare (EEO) e dos compostos isolados ácido caféico, ácido p-cumarico, ácido rosmarínico, quercetina, luteolina, carnosol, ácido carnósico, campferol e apigenina contra o EAV. Os ensaios foram realizados com concentrações não citotóxicas. A atividade antiviral foi monitorada inicialmente por um ensaio de inibição de efeito citopático (CPE) em células RK13 na presença ou ausência do EEO. Células pré-incubadas com o EEO foram também examinadas para a presença de efeito profilático. Inativação direta do EAV pelo EEO e pelos compostos isolados foi avaliada mediante incubação a 37C ou 20C. Após o período de incubação, a infectividade foi imediatamente determinada por titulação viral em cultivo celular sendo expresso como dose infectiva a 50% (TCID50)/100 µL. Houve significativa atividade virucida do EEO e dos compostos ácido caféico, ácido p-cumarico, quercetina, ácido carnósico e campferol. Quando o EEO foi adicionado após a infecção, o EEO inibiu a replicação do vírus nas células infectadas, o que foi evidenciado pela redução significativa do título viral. Os resultados fornecem evidências de que o EEO possui efeito anti-EAV.Entre os principais compostos presentes avaliados, ácido caféico, ácido p-cumarico, ácido carnósico, campferol e, principalmente, quercetina, contribuíram para a atividade antiviral do extrato. O EEO pode representar um bom protótipo para o desenvolvimento de um novo agente antiviral, sendo promissor para combater infecções por arterivírus.