Antimicrobial potential of pyroligneous extracts a systematic review and technological prospecting

Abstract Pyroligneous extract is applied in diverse areas as an antioxidant, an antimicrobial, and an anti-inflammatory agent. The discovery of new cost-effective antimicrobial agents of natural origin remains a challenge for the scientific community. This study aimed to conduct a systematic review and a technological forecasting of the existent evidence regarding the use of pyroligneous extract as a potential antimicrobial agent. Studies were identified through an investigation of various electronic databases: PubMed, SciFinder, Web of Science, Scopus, Scielo, Google scholar, and ProQuest. Patents were searched through INPI, Google patents, Espacenet, Patents online, USPTO, and WIPO. The literature on antimicrobial activity of pyroligneous extract are limited given the short duration of studies and variability in study design, use of pyroligneous preparations, and reports on results. However, evidence suggests the potential of pyroligneous extract as a natural antimicrobial agent. The most studied activity was the role of PE as a food preservative. However, pyroligneous extracts are also effective against pathogenic bacteria in the oral microflora and treatment of candidal infections. Further research is needed using standardized preparations of pyroligneous extracts to determine their long-term effectiveness and ability as antimicrobial agents.

Antimicrobial potential of pyroligneous extracts - a systematic review and technological prospecting

Pyroligneous extract is applied in diverse areas as an antioxidant, an antimicrobial, and an anti-inflammatory agent. The discovery of new cost-effective antimicrobial agents of natural origin remains a challenge for the scientific community. This study aimed to conduct a systematic review and a technological forecasting of the existent evidence regarding the use of pyroligneous extract as a potential antimicrobial agent. Studies were identified through an investigation of various electronic databases: PubMed, SciFinder, Web of Science, Scopus, Scielo, Google scholar, and ProQuest. Patents were searched through INPI, Google patents, Espacenet, Patents online, USPTO, and WIPO. The literature on antimicrobial activity of pyroligneous extract are limited given the short duration of studies and variability in study design, use of pyroligneous preparations, and reports on results. However, evidence suggests the potential of pyroligneous extract as a natural antimicrobial agent. The most studied activity was the role of PE as a food preservative. However, pyroligneous extracts are also effective against pathogenic bacteria in the oral microflora and treatment of candidal infections. Further research is needed using standardized preparations of pyroligneous extracts to determine their long-term effectiveness and ability as antimicrobial agents.(AU)

In vitro study on the antimicrobial effect of hydroalcoholic extracts from Mentha arvensis L. (Lamiaceae) against oral pathogens / Estudo in vitro do efeito antimicrobiano dos extratos hidroalcólicos de Mentha arvensis L. (Lamiaceae) contra patógenos orais

In vitro tests could be a valuable tool for the evaluation of medicinal plants' antimicrobial activity. Mentha arvensis of the Lamiaceae family is one of the most frequently traditional plants used in Brazil. Hydroalcoholic extracts of M. arvensis were analyzed for antimicrobial activity on Streptococcus mutans, Streptococcus sobrinus and Candida albicans. Three different assays (agar diffusion, broth macro- and micro-dilution methods) were used to evaluate antimicrobial activity. Although hydroalcoholic extracts of M. arvensis did not show any antibacterial effect, its antifungal activity against C. albicans was revealed. According to the micro-dilution broth assay, MIC of the hydroalcoholic extract from leaves of M. arvensis on Candida albicans strains ranged between 625 and 2500 µg mL-1. Results suggest that M. arvensis hydroalcoholic extract may be considered a potentially antifungal agent against C. albicans, and a possible item for human antibiotic therapy. However, further biological tests on the plant's efficacy and side-effects are necessary before its use on humans.

Testes in vitro podem ser uma ferramenta valiosa para a avaliação da atividade antimicrobiana de plantas medicinais. Mentha arvensis é uma das plantas medicinais brasileiras mais frequentemente utilizadas e pertence à família Lamiaceae. No presente estudo, extratos hidroalcólicos de M. arvensis foram analisados quanto à sua atividade antimicrobiana sobre Streptococcus mutans, Streptococcus sobrinus e Candida albicans. Três diferentes ensaios (métodos de difusão em ágar, macro e microdiluição em caldo) foram utilizados para avaliação da atividade antimicrobiana. Embora os extratos hidroalcólicos de M. arvensis não demonstraram qualquer efeito antibacteriano, eles apresentaram atividade antifúngica contra C. albicans. Baseado no ensaio de microdiluição em caldo, a CIM do extrato hidroalcólico das folhas de M. arvensis sobre cepas de C. albicans variaram de 625 a 2500 µg mL-1. Estes achados sugerem que o extrato hidroalcólico de M. arvensis pode ser considerado um agente antifúngico em potencial contra C. albicans, e um possível candidato para antibioticoterapia humana. Contudo, mais testes biológicos sobre a eficácia e efeitos adversos desta planta são necessários antes do seu uso em humanos.

Avaliação dos métodos de etest e microdiluição em caldo para o estudo da suscetibilidade do sporothrix schenckii com o itraconazol / Evaluation of Etest and Broth Microdiluition Methods for Itraconazole susceptibility testing of Sporothrix schenckii

A frequente ocorrência de isolados fúngicos resistentes aos fármacos antifúngicos estimulou os avanços das técnicas de antifungigrama com a padronização das técnicas pelo CLSI. Porém, os métodos são ineficientes e com pouca praticidade na execução em laboratórios clínicos. Nesse contexto surgiram as técnicas comerciais, como o ETEST, que, dentre outras vantagens, demonstra maior facilidade na sua execução em relação às técnicas preconizadas pelo CLSI. O estudo utilizou o ETEST e o método de microdiluição em caldo realizado de acordo com o CLSI, para determinar a suscetibilidade de isolados de Sporothrix schenckii com o itraconazol. O CLSI emprega o meio RPMI 1640 e a leitura da CIM após o período de incubação de 72h a 35ºC. No estudo, foi determinada a CIM pelo ETEST utilizando o meio ágar Sabouraud dextrose e realizando a leitura após 72 horas de incubação a 35ºC. A análise de variância feita pelo teste de T pareado não demonstrou diferenças estatísticas entre os valores das CIMs obtidos pela técnica de microdiluição em caldo (MIC entre 0,219 e 0,875 µg/mL) e o ETEST (MIC entre 0,032 e 2,0 µg/mL), porém o coeficiente de correlação (R) foi negativo, provavelmente pelo pequeno número de amostras. Esses resultados estimulam mais estudos que confirmem a aplicação do ETEST para avaliar a suscetibilidade do S. schenckii com o itraconazol.

The frequent occurrence of resistant isolated fungi againstantifungal drugs stimulated advances in the antifungigram techniques, which were standardized by CLSI. However, the methods have been inefficient and impractical to be executed in clinical laboratories. Within this context, commercial techniques have been developed, being ETEST one of them. ETEST has proved to be easier to execute when compared to the techniques approved by the CLSI. This study used the ETEST and the microdilution method, performed according to CLSI, for determining the in vitro susceptibility of isolates of Sporothrix schenckii against itraconazole. The CLSI uses RPMI 1640 medium and the reading of MIC after the period of incubation of 72h at 35ºC. MIC was determined by the ETEST, being Sabouraud dextrose agar used as medium, and the reading performed after 72 hours of incubation at 35ºC. The variance analysis, analyzed by T-paired test, did not demonstrate statistical differences among the CIM values obtained by the microdilution technique in broth (MIC among 0.219 and 0.875 µg/mL) and ETEST (MIC among 0.032 and 2.0 µg/mL). However, the correlation coefficient (R) was negative, probably because of the small number of samples. These results show the necessity of further studies to assess the application of ETEST to evaluate the susceptibility of S. schenckii against the itraconazol.

Avaliação dos métodos de etest e microdiluição em caldo para o estudo da suscetibilidade do sporothrix schenckii com o itraconazol / Evaluation of Etest and Broth Microdiluition Methods for Itraconazole susceptibility testing of Sporothrix schenckii

A frequente ocorrência de isolados fúngicos resistentes aos fármacos antifúngicos estimulou os avanços das técnicas de antifungigrama com a padronização das técnicas pelo CLSI. Porém, os métodos são ineficientes e com pouca praticidade na execução em laboratórios clínicos. Nesse contexto surgiram as técnicas comerciais, como o ETEST, que, dentre outras vantagens, demonstra maior facilidade na sua execução em relação às técnicas preconizadas pelo CLSI. O estudo utilizou o ETEST e o método de microdiluição em caldo realizado de acordo com o CLSI, para determinar a suscetibilidade de isolados de Sporothrix schenckii com o itraconazol. O CLSI emprega o meio RPMI 1640 e a leitura da CIM após o período de incubação de 72h a 35ºC. No estudo, foi determinada a CIM pelo ETEST utilizando o meio ágar Sabouraud dextrose e realizando a leitura após 72 horas de incubação a 35ºC. A análise de variância feita pelo teste de T pareado não demonstrou diferenças estatísticas entre os valores das CIMs obtidos pela técnica de microdiluição em caldo (MIC entre 0,219 e 0,875 µg/mL) e o ETEST (MIC entre 0,032 e 2,0 µg/mL), porém o coeficiente de correlação (R) foi negativo, provavelmente pelo pequeno número de amostras. Esses resultados estimulam mais estudos que confirmem a aplicação do ETEST para avaliar a suscetibilidade do S. schenckii com o itraconazol.(AU)

The frequent occurrence of resistant isolated fungi againstantifungal drugs stimulated advances in the antifungigram techniques, which were standardized by CLSI. However, the methods have been inefficient and impractical to be executed in clinical laboratories. Within this context, commercial techniques have been developed, being ETEST one of them. ETEST has proved to be easier to execute when compared to the techniques approved by the CLSI. This study used the ETEST and the microdilution method, performed according to CLSI, for determining the in vitro susceptibility of isolates of Sporothrix schenckii against itraconazole. The CLSI uses RPMI 1640 medium and the reading of MIC after the period of incubation of 72h at 35ºC. MIC was determined by the ETEST, being Sabouraud dextrose agar used as medium, and the reading performed after 72 hours of incubation at 35ºC. The variance analysis, analyzed by T-paired test, did not demonstrate statistical differences among the CIM values obtained by the microdilution technique in broth (MIC among 0.219 and 0.875 µg/mL) and ETEST (MIC among 0.032 and 2.0 µg/mL). However, the correlation coefficient (R) was negative, probably because of the small number of samples. These results show the necessity of further studies to assess the application of ETEST to evaluate the susceptibility of S. schenckii against the itraconazol.(AU)

Análise microbiológica de salame tipo alemão vendido em feiras-livres / Microbiological analysis of german salami sold in free markets

Os alimentos são passíveis de contaminação por diferentes agente etiológicos, tanto microrganismo como suas toxinas. O presente estudo objetivou analisar microbiologicamente amostras de salames do tipo alemão produzidos artesanalmente e comercializados nas feiras livres da cidade de Pelotas, RS, Brasil. Esta cidade conta com 12 feiras livres cadastradas na Prefeitura e distribuídas em diferentes locais sendo que a realização de cada uma ocorre semanalmente. Os salames foram adquiridos aleatoriamente em cada uma das feiras e a análise microbiológica foi realizada no Laboratório de Microbiologia do Instituto de Biologia da UFPel, sendo a metodologia realizada conforme legislação em vigor da Agência Nacional de Vigilância Sanitária –ANVISA. O alimento foi encontrado em dez (83,3%) feiras, totalizando dez amostras. Após a análise, observou-se que em somente uma (10%) amostra isolou-se Staphylococcus coagulase positiva. Quanto à Salmonella sp. e Coliformes a 45ºC não houve isolamento em nenhuma amostra. Esta análise microbiológica demonstrou que as amostras de salame “alemão” comercializadas nas feiras livres de Pelotas estão livres de contaminação pelos microrganismos entéricos patogênicos Salmonella sp e Coliformes a 45ºC, o que representa um aspecto positivo para este comércio. Entretanto, a presença de Staphylococus coagulase positiva, em uma das amostras, evidencia risco de intoxicação alimentar.(AU)

Foods are susceptible to contamination for different etiologic agents, as microorganisms as their toxins. The aim of the present study was to evaluate microbiologically samples of homemade German-type salamis commercializedin free markets from the city of Pelotas, RS, Brazil. This city has 12free markets registered in the city counciland they are distributed in different places and happen weekly. The salamis were randomly acquired in each free market and the microbiological analysis was carried out in the Laboratory of Bacteriology from the Biology Institute at the UFPel, according to the present legislation of the Brazil's National Health Surveillance Agency (ANVISA).The food was found in ten (83,3%) free markets, totalizing ten samples. After the analysis, it was observed that just in one (10%) sample it was isolated coagulase-positive Staphylococcus. Regarding to Salmonella sp. and Coliforms at 45°C there was no isolating in any sample. This microbiological analysis demonstrated that the German-type salamis' samples sold in free markets of Pelotas are free of contamination by the enteric pathogens Salmonella sp. and Coliforms at 45°C, which represents a positive aspect for this commerce. Nevertheless, the presence of coagulase-positive Staphylococcus, in one of these samples, suggests the risk of food intoxication. (AU)