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Plants defend themselves against pathogens with production of antimicrobial peptides (AMPs). Herein we describe the discovery of a new antifungal and antibacterial peptide from fruits of Capsicum annuum that showed similarity to an already well characterized family of plant AMPs, thionins. Other fraction composed of two peptides, in which the major peptide also showed similarity to thionins. Among the obtained fractions, fraction 1, which is composed of a single peptide of 7 kDa, was sequenced by Edman method and its comparative sequence analysis in database (nr) showed similarity to thionin-like peptides. Tests against microorganisms, fraction 1 presented inhibitory activity to the cells of yeast Saccharomyces cerevisiae, Candida albicans, and Candida tropicalis and caused growth reduction to the bacteria species Escherichia coli and Pseudomonas aeruginosa. Fraction 3 caused inhibitory activity only for C. albicans and C. tropicalis. This fraction was composed of two peptides of ∼7 and 10 kDa, and the main protein band correspondent to the 7 kDa peptide, also showed similarity to thionins. This plasma membrane permeabilization assay demonstrates that the peptides present in the fractions 1 and 3 induced changes in the membranes of all yeast strains, leading to their permeabilization. Fraction 1 was capable of inhibiting acidification of the medium of glucose-induced S. cerevisiae cells 78% after an incubation time of 30 min, and opposite result was obtained for C. albicans. Experiments demonstrate that the fraction 1 and 3 were toxic and induced changes in the membranes of all yeast strains, leading to their permeabilization.

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O uso indiscriminado de antimicrobianos determina um processo de seleção de micro-organismospatogênicos que apresentam resistência à maioria dos compostos químicos utilizados na agropecuária e namedicina. Uma alternativa eficaz e econômica tem sido o desenvolvimento e o uso de produtos naturais compropriedades antimicrobianas. Este trabalho teve como objetivo avaliar a atividade antimicrobiana deextratos de Punica granatum, Anacardium occidentale e Psidium guajava frente a cepas de Stafhylococcusaureus, Stafhylococcus epidermidis, Escherichia coli e Pseudomonas aeruginosa. A investigação foiconduzida utilizando o método de difusão em ágar e inóculo bacteriano padronizado, com poços perfuradosno ágar, nos quais foram adicionados volumes conhecidos das substâncias testadas: gentamicina (controlepositivo), DMSO (controle negativo) e extratos vegetais. As placas foram incubadas a 37 ºC por 24 horas emensurado o diâmetro dos halos de inibição. Os extratos diclorometânico e metanólico das cascas de Punicagranatum e metanólicos das folhas de Anacardium occidentale e Psidium guajava, na concentração de 1g/ml, foram mais efetivos contra as cepas de S. aureus, S. epidermidis, E.coli. Posteriormente, esses extratosforam utilizados para o teste de sinergismo em associação a antibióticos padronizados, no qual foi observadoefeito sinérgico frente às bactérias testadas, com exceção da P. aeruginosa.Palavras-Chave: Extratos fitoquímicos. Agentes antibacterianos. Sinergismo farmacológico.

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Introduction: Sporotrichosis is an infectious fungal zoonosis associated with traumatic implantation in the skin of dimorphic fungi of the Sporothrix schenckii complex. The objective of this study was to diagnose sporotrichosis in patients in the city of Campos dos Goytacazes, and to establish correlations between positive laboratory results and dermatological and topographical aspects of the lesions and personal traits of the patients, such as sex, age and profession. Methodology: We collected samples from 22 patients with suspect lesions, which were sent to the laboratory for direct microscopic analysis after Gram staining, followed by mycological culture by seeding the material in 4% Sabouraud dextrose agar (Himedia®) supplemented with chloramphenicol (50 mg/Lt) and cycloheximide (400 mg/Lt - Sigma-Aldrich, USA). The dishes were incubated at 25-30oC. For confirmation of the diagnosis, the strains isolated in mycelial form were converted to yeast form by culture in yeast-peptone-dextrose (YPD) agar at 37oC for up to 15 days. Results: The positive results demonstrated that the disease was most frequently diagnosed in women between the ages of 19 and 60 years, and that 18 (81.8%) of the patients reported having contact with pet cats. The occupations of those positive for sporotrichosis were not related to the disease. The upper limbs were the body region most often afflicted, with observation in the majority of cases of ulcerated lesions, although five patients also had nodular lesions. Additionally, the observation of lymphatic cords was frequent. Conclusion: In recent years, sporotrichosis has been diagnosed with relative frequency in Campos dos Goytacazes, causing great concern among public health officials and practitioners.

Sporotrichosis is a chronic and subacute mycosis causing epidemiological outbreaks involving sick cats and humans in southeastern Brazil. The systemic disease prevails in cats and in humans, with the symptoms restricted to the skin of immunocompetent individuals. Under these conditions, the prolonged treatment of animals and cases of recurrence justify the discovery of new treatments for sporotrichosis. This work addresses the antifungal activity of silver salts of Keggin-type heteropolyacid salts (Ag-HPA salts) such as Ag 3 [PW 12 O 40 ], Ag 6 [SiW 10 V 2 O 40 ], Ag 4 [SiW 12 O 40 ] and Ag 3 [PMo 12 O 40 ] and interactions with the antifungal drugs itraconazole (ITC), terbinafine (TBF) and amphotericin B (AMB) on the yeast and mycelia forms of Sporothrix spp. Sporothrix spp. yeast cells were susceptible to Ag-HPA salts at minimum inhibitory concentration (MIC) values ranging from 8 to 128 μg/ml. Interactions between Ag 3 [PW 12 O 40 ] and Ag 3 [PMo 12 O 40 ] with itraconazole and amphotericin B resulted in higher antifungal activity with a reduction in growth and melanization. Treated cells showed changes in cell membrane integrity, vacuolization, cytoplasm disorder, and membrane detachment. Promising antifungal activity for treating sporotrichosis was observed for the Ag-HPA salts Ag 3 [PMo 12 O 40 ] and Ag 3 [PW 12 O 40 ], which have a low cost, high yield and activity at low concentrations. However, further evaluation of in vivo tests is still required.

ResumoEm um total de 364 vacas portadoras de mastite subclínica e 1398 quartos mamários examinados, 555 amostras de leite foram coletadas durante os anos de 1996 e 1997 de 64 propriedades, em 15 municípios da região Norte/Noroeste do Estado do Rio de Janeiro. As amostras de leite foram testadas a partir de CMT (California Mastitis Test) e 128 cepas de Staphylococcus aureus foram isoladas e identificadas após análise de rotina laboratorial. Antibiogramas foram realizados, testando-se 15 antibióticos diferentes para definir o padrão de sensibilidade. Nos testes para os b-lactâmicos 96,1% das cepas foram resistentes (R), nenhuma cepa se enquadrou na faixa intermediária ( I ) e 3,9% mostraram sensibilidade (8) à penicilina; seus derivados semi-sintéticos foram oxacilina 87,0 R, 5,3% I e 7,6% 8; ampicilina 99,2 R e 0,8% 8 e nenhuma intermediária, amoxicilina 88,2% R, 9,8% I e 2,0 8; para os b-lactâmicos cefalotina 96% 8, 0,9% R, 3,1% I e cefoxitina 71 ,6% 8, 5,5% R e 22,8% I. Todas as cepas foram 100% sensíveis à gentamicina, sulfazotrim e vancomicina. Nenhuma das cepas isoladas foi resistente à meticilina quando utilizada a concentração padrão de 25mg/ml da droga para testes de cepas de origem humana {clone brasileiro MR8A III::B:A) Palavras-chave: mastite bovina; meticilina; resistência; Staphylococcus aureus. AbstractFrom 364 subclinical mastitic dairy cows and 1398 quarters examined, a total of 555 milk samples were collected during 1996 and 1997 in 64 dairy farms in 15 municipalities of Northern 8tate of Rio de Janeiro, Brazil. Ali samples were CMT (California Mastitis Test) tested and 128 strains of Staphy/ococcus aureus identified after routine laboratorial analyses. Fifteen different antibiotic tests were performed and susceptibility profiles of the strains were evaluated. For beta-lactamic, 96,1% of the strains were resistant (R), 3,9% susceptible (8) and none was intermediary ( I ) to Penicillin. Towards penicillin semi-synthetic beta-lactamics, the strains showed 87%R, 7,6%8 and 5,3%1 to Oxacillin, 99,2%R, 0,88 0%1 to Ampicillin and 88,2%, 2,0%8 and 9,8%1 to Amoxicillin. Towards Cephalotin, 96% of strains were 8, 3,1 %R, and 0,9%1. For Cephoxitin the figures were 71%8, 5,5%R and 22,8%1. Ali strains tested (1 00%) were susceptible to Gentamycin, 8ulphazotrim and Vancomycin. None of the Staphylococcus aureus strains isolated were Methicillin-resistant to 25mg/ml a dose used to test S. aureus strains from human origin (Brazilian MR8A III::B:A) Keywords: bovine mastitis, methicillin, resistance, Staphylococcus aureus. IntroduçãoMastites são processos inflamatórios agudos ou crônicos das glândulas mamárias, caracterizados pelo aumento de células somáticas no leite, proveniente da glândula afetada e considerada a doença de maior custo aos criadores de gado de leite, resultando em perdas econômicas (DeGraves e Fetrow, 1993 ; Germano e Germano, 1995).Os quadros de mastite prolongada ou crônica levam a contí-nua mudança na constituição dos tecidos da glândula e tecidos produtores de leite que são substituídos por t...