RESUMO: Agaricus brasiliensis possui compostos bioativos que apresentam atividade antimicrobiana e induz mecanismos de defesa em plantas contra patógenos. O objetivo deste trabalho foi avaliar a aplicação da suspensão miceliada aquosa de A. brasiliensis no controle do míldio (Plasmopara viticola) e indução de resistência em videiras Isabel Precoce. Os tratamentos foram: 0, 1, 5, 10, 15 e 20% da suspensão miceliada aquosa de A. brasiliensis, além do tratamento com acibenzolar-S-metil. As variáveis analisadas foram: germinação de esporangiósporos; severidade da doença, representada pela área abaixo da curva de progresso da doença; atividade da enzima catalase; peroxidase e polifenoloxidase. As doses 10, 15 e 20% de suspensão miceliada aquosa de A. brasiliensis proporcionaram redução de aproximadamente 80% na germinação dos esporangiósporos de P. viticola. Os tratamentos não apresentaram efeitos significativos na redução da área abaixo da curva de progresso da doença do míldio e na atividade da enzima polifenoloxidase. A dose de 10% da suspensão miceliada aquosa de A. brasiliensis reduziu a atividade de catalase e induziu a atividade da peroxidase. A suspensão miceliada aquosa de A. brasiliensis apresentou efeito fungitóxico na germinação de esporangióporos, entretanto não foi suficiente para reduzir a severidade do míldio da videira Isabel Precoce, mesmo atuando na atividade das enzimas catalase e peroxidase. Assim, experimentos deverão ser realizados para verificar a viabilidade das estruturas reprodutivas do patógeno exteriorizadas nas videiras quando tratadas com suspensão miceliada aquosa de A. brasiliensis.

ABSTRACT: Agaricus brasiliensis include bioactive compounds that can act as antibiotics, bacteriostatic, fungistatic and nematostatic substances. In this sense, this study aimed to evaluate the effect of a single application of aqueous mycelial suspension (AMS) of A. brasiliensis in control of downy mildew (Plasmopara viticola) and resistance induction in ‘Isabel Precoce’ grapevines under greenhouse conditions. Treatments consisted of three doses of 1%, 5%, 10%, 15% and 20% AMS A. brasiliensis, as well as treatment with acibenzolar-S-methyl (ASM). The variables analyzed were: sporangiospore germination, disease severity, represented by the area under the disease progress curve (AUDPC), catalase enzyme activity, peroxidase and polyphenol. The 10%, 15% and 20% doses of AMS caused approximately 80% reduction in germination of P. viticola sporangiospores. The treatments did not show significant effects in reducing both the AUDPC of mildew and polyphenol oxidase enzyme activity. The A. brasiliensis aqueous mycelial suspension showed a fungitoxic effect on the germination of sporangiopores; however, it was not enough to reduce the severity of mildew in the ‘Isabel Precoce’ grapevines, even when acting on the catalase and peroxidase enzymes. Thus, experiments should be performed to verify the viability of the reproductive structures of the pathogen externalized in the vines when treated with A. brasiliensis AMS.

The most promising microorganisms for use as starter cultures are those isolated from the native microbiota of traditional fermented products. The aim of this study was to evaluate the use of lactic acid bacteria selected from the native microbiota of sausages produced by spontaneous fermentation as starter cultures for the production of sausage. Strains of Lactobacillus plantarum 503 and 341 have the potential for use as starter cultures in the manufacture of Italian sausage type. The population of lactic acid bacteria in sausages was >8 log CFU.g-1 during fermentation, which caused the pH to decrease to <4.5. This decrease in pH and the water activity of < 0.90 of sausages ensures the safety and preservation of this product. Sausages produced with these lactic cultures fulfill the requirements for microbiological quality and composition of Italian sausage type. Our results suggest the possibility of using these starter cultures for the production of sausages with peculiar characteristics that contribute to the identity of the product.

O estudo da ecologia de salames fermentados faz-se necessário para entender as mudanças físicas e químicas que ocorrem durante a fermentação e maturação. O objetivo deste trabalho foi determinar as características microbiológicas de salames produzidos por fermentação espontânea. Foram analisadas cinquenta amostras de salames de diferentes pequenas indústrias em relação à seguinte microbiota: bactérias aeróbias mesófilas; Micrococcaceae; bolores e leveduras; bactérias lácticas; coliformes totais e fecais; Staphylococcus coagulase positiva; e Salmonella. Na grande maioria das amostras (72%), a presença de bactérias lácticas foi superior a 10(6) ufc.g-1, sendo que as amostras com as maiores contagens tiveram quantidades acima de 10(8) ufc.g-1. A concentração de Micrococcaceae, na maioria das amostras, ficou entre 10(5) e 10(7) ufc.g-1. Em relação à concentração de bolores e leveduras, houve uma grande variação entre as amostras, com quantidades próximas a 10² ufc.g-1 até 10(6) ufc.g-1. Pelos dados obtidos, concluiu-se que, das amostras analisadas, 24% estão em desacordo com as normas vigentes no Brasil, pois apresentam quantidades superiores do máximo permitido para coliformes a 45 ºC ou Staphylococcus coagulase positiva.

The study of the ecology of fermented sausage is fundamental to understand the physical and chemical changes that happen during fermentation and maturation. The aim of the present study was to determine the microbiological characteristics of sausages produced by spontaneous fermentation. Fifty samples of sausages produced in the South of Brazil by different small manufacturers were analyzed for the following microbiota: aerobic mesophilic bacteria; Micrococcaceae; mold and yeast; lactic acid bacteria; total and fecal coliforms; coagulase-positive Staphylococcus, and Salmonella. In most samples (72%), the count of lactic bacteria was higher than 6 log10 cfu.g-1, and the samples with the highest counts were above 8 log10 cfu.g-1. The counts of Micrococcaceae in most samples were between 5 log10 and 7 log10 cfu.g-1. With respect to the presence of molds and yeasts, there was a significant variation among the samples with counts ranging from 2 log10 cfu.g-1 and 6 log10 cfu.g-1. From the data obtained, it was possible to conclude that 24% of the analyzed samples did not comply with the current law in Brazil since the levels of fecal coliforms or coagulase-positive Staphylococcus exceeded the maximum limit allowed.

Propolis is mostly used as hydroalcoholic extract. Recently there has been a growing number of patents dealing with new solvents for preparing propolis extracts. This study aimed to prepare edible oil propolis extracts and compare their chemical composition and biological activity with ethanolic propolis extracts. ESI-MS and spectrophotometric methods were used for qualitative and quantitative analyses, respectively. Antibacterial activity was evaluated by diffusion in agar. Cytotoxicity was tested by MTT assay using tumor cell lines. The oil is able to extract bioactive compounds from propolis. Further studies are needed to improve extraction efficiency and to characterize the active components.

O objetivo deste trabalho foi produzir Beauveria bassiana por fermentação no estado sólido em resíduos agro-industriais e otimizar as condições de cultivo. Batata-refugo, polpa de café e bagaço de cana de açúcar foram testados. A mistura de batata-refugo e de bagaço de cana de açúcar (60:40%), com granulometria de 2 a 0,8 mm foi escolhida como melhor substrato/suporte. Em frascos de Erlenmeyer a produção de esporos foi maior com as seguintes condições: pH 6,0; temperatura de incubação de 26º C; taxa de inóculo de 10(7) esporos.g-1 de matéria seca; e umidade inicial de 75%. Em bioreator do tipo coluna com aeração forçada, as condições otimizadas possibilitaram uma produção máxima de esporos no 10º dia de fermentação, obtendo-se 1,07x10(10) esporos.g-1 de matéria seca. A análise respirométrica desta fermentação permitiu correlacionar o desenvolvimento do fungo com a produção de esporos.

The purpose of this work was to produce Beauveria bassiana by Solid-State Fermentation using agro-industrial residues and optimizing the cultivation conditions. Refused potatoes, coffee husks and sugar-cane bagasse were tested. The blend of refused potatoes and sugar-cane bagasse (60-40%) with particle size in the range of 0.8-2 mm was used in the fermentation experiments. In Erlenmeyer flasks the best spore production was achieved with the following conditions: incubation temperature 26º C; initial pH 6.0; inoculum concentration 10(7) spores.g-1.dw and initial moisture 75%. In the column type reactor using forced aeration under the optimized conditions, the maximum production (1.07x10(10)spores.g-1.dw) was obtained at the 10th day of fermentation. The respirometric analyses of the fermentation showed a strong correlation between fungal growth and spore production.