The search for new compounds of plant origin with antimicrobial activity has been the goal of many research groups, due to the increase in the number of microorganisms resistant to antimicrobials. The objective of this study was to evaluate the antimicrobial and antioxidant activity of two plant species, Tabebuia aurea (“paratudo”) and Cordia glabrata (“louro branco”), present in the state of Mato Grosso. The plant material (leaves and flowers) was extracted by maceration in 70% ethanol (Et) and polar hexane (Hex) (non-polar solvent). The determination of the antimicrobial activity was carried out by broth microdilution technique, and the antioxidant potential determined by the DPPH free radical method. In the evaluation of the antibacterial activity, the ethanolic extract of C. glabrata leaves presented better antibacterial potential for Staphylococcus aureus, revealing a minimum inhibitory concentration (MIC) of 125 μg / mL. However, for strains of Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium, all extracts of C. glabrata showed MICs of 2000 μg / mL or higher. The ethanolic and hexanic extracts of T. aurea flowers and leaves did not show promising antibacterial potential for any of the tested strains. In the evaluation of antifungal activity against Candida albicans and Candida parapsilosis, the hexanic extract of C. glabrata leaves presented weak to moderate activity only for the C. albicans strain (MIC = 1000 μg / mL). The remaining extracts of C. glabrata and the extracts of T. aurea were not promising against the tested yeasts, showing inhibitory concentrations equal to or greater than 2000 μg / mL. In the determination of the antioxidant potential, the polar extracts (Et 70%) had a higher capacity to sequester the DPPH radical than the capacity obtained for the apolar extracts (Hex). The tests revealed promising antibacterial activity for Staphylococcus aureus and high antioxidant potential of the hydroethanolic extracts of leaves and flowers of C. glabrata, respectively.

É comum indivíduos saudáveis serem colonizados pelo Staphylococcus aureus, sendo o mesmo encontrado em diversas áreas do corpo, com maior frequência na cavidade nasal. Apesar de ser membro de microbiota, esse micro-organismo pode estar relacionado com uma variedade de doenças infecciosas. Em décadas anteriores as infecções por S. aureus eram tratadas com facilidade através do uso da penicilina e moléculas semissintéticas de β-lactâmicos, como a meticilina e seu análogo oxacilina. Entretanto, dentro de um curto período, à resistência à meticilina, foi detectada em cepas de S. aureus (MRSA – metthicillin-resistante Staphylococcus aureus), passando de um organismo presente predominantemente em hospitais para uma causa comum de infecções também dentro da comunidade. Considerando a importância das infecções nosocomiais e na comunidade, o presente trabalho teve como objetivo a avaliação do perfil de colonização nasal e oral pelo S. aureus, bem como a determinação da resistência à meticilina/oxacilina, entre os estudantes do curso de Farmácia. Também foi avaliado o perfil geral de contaminação dos aparelhos celulares (tipo smartphones), verificando a presença de S. aureus. Amostras da cavidade nasal, orofaringe e da superfície (tela frontal) do aparelho celular dos acadêmicos, foram coletadas utilizando-se swabs estéreis e semeadas em Agar Sal Manitol e Agar Mueller Hinton. A avaliação do perfil de sensibilidade das cepas de S. aureus isoladas dos estudantes foi realizada por técnica de difusão em agar. Dos 50 voluntários empregados na pesquisa, 29 (58%) apresentaram amostras positivas para o S. aureus na cavidade nasal e/ou oral. Sendo que, 14 voluntários (28%) possuíam o S. aureus somente na cavidade nasal, 5 (10%) somente na cavidade oral e 10 voluntários (20%) apresentaram a bactéria em ambos os locais (cavidade nasal e orofaringe). Dos portadores da bactéria, um voluntário (3,4%) apresentou cepa MRSA. Na contagem de micro-organismos mesófilos aeróbios totais (nos aparelhos celulares), 100% das amostras obtiveram crescimento, sendo que 80% apresentaram contagens menores ou iguais a 5 UFC/cm2 da superfície frontal do smartphone. Na pesquisa de bactérias específicas, 9 (18%) celulares revelaram a presença de S. aureus. Através dos resultados foi possível observar que a maioria dos estudantes apresentam S. aureus colonizando a cavidade nasal e/ou oral, entretanto, não sendo verificada uma alta porcentagem de cepas resistentes a oxacilina/meticilina. Todos os acadêmicos apresentaram aparelhos com algum nível de contaminação microbiológica, sendo detectado o S. aureus apenas nos aparelhos dos estudantes que eram portadores nasais e/ou orais dessa bactéria.

Truffles are ascomycete hypogeous fungi belonging to the Tuberaceae family of the Pezizales order that grow in ectomycorrhizal symbiosis with tree roots, and they are known for their peculiar aromas and flavors. The axenic culture of truffle mycelium is problematic because it is not possible in many cases, and the growth rate is meager when it is possible. This limitation has prompted searching and characterizing new strains that can be handled in laboratory conditions for basic and applied studies. In this work, a new strain of Tuber borchii (strain SP1) was isolated and cultured, and its transcriptome was analyzed under different in vitro culture conditions. The results showed that the highest growth of T. borchii SP1 was obtained using maltose-enriched cultures made with soft-agar and in static submerged cultures made at 22 °C. We analyzed the transcriptome of this strain cultured in different media to establish a framework for future comparative studies, paying particular attention to the central metabolic pathways, principal secondary metabolite gene clusters, and the genes involved in producing volatile aromatic compounds (VOCs). The results showed a transcription signal for around 80% of the annotated genes. In contrast, most of the transcription effort was concentrated on a limited number of genes (20% of genes account for 80% of the transcription), and the transcription profile of the central metabolism genes was similar in the different conditions analyzed. The gene expression profile suggests that T. borchii uses fermentative rather than respiratory metabolism in these cultures, even in aerobic conditions. Finally, there was a reduced expression of genes belonging to secondary metabolite clusters, whereas there was a significative transcription of those involved in producing volatile aromatic compounds.

Truffles are ascomycete hypogeous fungi belonging to the Tuberaceae family of the Pezizales order that grow in ectomycorrhizal symbiosis with tree roots and are known for their peculiar aromas and flavors. Axenic culture of truffle mycelium is problematic because it is not possible in many cases, and the growth rate is meager when it is possible. This limitation prompts searching and characterizing new strains that can be handled in laboratory conditions for basic and applied studies. In this work, a new strain of Tuber borchii (strain SP1) has been isolated and cultured, and its transcriptome has been analyzed under different in vitro culture conditions. The results show that the best T. borchii SP1 growth was obtained using maltose-enriched cultures made with soft-agar and in static submerged cultures made at 22ºC. The transcriptome analysis of this strain cultured in different media indicated that most of the gene transcription effort is due to a limited number of genes (20% of genes account for 80% of the transcription), that the transcription profile of the central metabolism genes was similar in the different conditions analyzed with a transcription signal detected for around 80% of the annotated genes. The gene expression profile suggests that T. borchii uses a fermentative rather than respiratory metabolism, even in aerobic conditions. Finally, there is a reduced expression of genes belonging to secondary metabolite clusters, whereas there is a significative transcription of those involved in producing volatile aromatic compounds.