It was synthesized nine polyoxygenated chalcones with a potential and safe use as antioxidant, antimicrobial and anti-inflammatory therapies. Chalcones obtained by Claisen-Schmidt condensation were studied as antioxidant, inhibitors of human 5-lipoxygenase, antifungal, antibacterial and antibiotic resistance modifiers. Two chalcones with catecholic moieties were able to strongly decrease the minimum inhibitory concentration (MIC) of methicillin against methicillin-resistant Staphylococcus aureus, increase the antiradical activity and significantly inhibit the human 5-lipoxygenase. Only one of these chalcones was active synergistically with methicillin. Chalcones with methoxyl substituents at different positions displayed the best activities against Cryptococcus neoformans. Only one chalcone showed good activity against the plant pathogenic bacteria Pseudomonas syringae whose half maximal inhibitory concentration (IC50) value (2.5 µg mL-1) was similar to that observed with the antibiotic streptomycin (2.9 µg mL-1). These simple chalcones have safe potential uses in antioxidant, antimicrobial and anti-inflammatory therapies.

Os extratos, frações e ácido elágico, isolados da entrecasca de Lafoensia pacari A. St.-Hil., Lythraceae, foram testados in vitro para atividade antifúngica, frente a um painel de leveduras, hialo-hifomicetos e dermatófitos, utilizando o método de microdiluição. O extrato EtOH, frações e ácido elágico exibiram atividade contra Candida spp. e Saccharomyces cerevisiae com valores de CIM entre 250-1000 µg/mL, porιm não mostraram ação contra fungos filamentosos e dermatófitos (CIM>1000 µg/mL). Os extratos ativos foram avaliados nos ensaios de inibição do crescimento das hifas de Neurospora crassa, no teste do sorbitol, e pelo estudo do efeito do ergosterol na CIM do ácido elágico. Os extratos ativos, frações e ácido elágico mostraram zonas manchadas ao redor dos discos de papel e induziram malformações nas hifas. Além disso, a CIM do ácido elágico contra Saccharomyces cerevisiae passou de 62 para 250 µg/mL na presença do sorbitol 0,8 M, sugerindo que o ácido elágico provavelmente poderia exercer ação na parede celular fúngica. Esses resultados indicam que o ácido elágico pode ser o principal composto antifúngico de Lafoensia pacari, sugerindo que o modo de ação antifúngico desses extratos e ácido elágico poderia estar associado à inibição da parede celular fúngica.

Stem-bark extracts, fractions and the isolated constituent, ellagic acid of Lafoensia pacari St. Hil. (Lythraceae) were in vitro assayed for antifungal activity against a panel of yeasts, hialohyphomycetes as well as dermatophytes with the microbroth dilution method. The EtOH extract and its fractions and ellagic acid exhibited activity against Candida spp and Saccharomyces cerevisiae with MIC values between 250-1000 µg/mL, but they showed no action against filamentous fungi and dermatophytes (MIC>1000 µg/mL). Active extracts were evaluated in Neurospora crassa hyphal growth inhibition and sorbitol assays and then the effect of ergosterol on the MIC of ellagic acid was studied. The active extracts and its fractions and ellagic acid showed a blotchy zone around the paper disk and induced malformations of the hypha. Besides, MIC of the ellagic acid against the Saccharomyces cerevisiae was raised from 62 to 250 µg/mL in the presence of sorbitol 0.8 M, suggesting that the ellagic acid would probably exert its action on fungal cell wall. These results indicate that ellagic acid might be the main active antifungal compound of Lafoensia pacari and further suggest that the mode of antifungal action of these extracts and ellagic acid could be associated with the inhibition of fungal cell wall.

A síntese, a caracterização espectroscópica e os resultados biológicos de novas séries de 2-(4-piridil)-1,2,3,4-tetrahidroquinolinas e seus precursores, -N-aril-N-[1-(4-piridil)but-3-enil]aminas, são descritos. Foi encontrado que ambos, precursores substituídos γ-piridil e os produtos finais, as tetrahidroquinolinas, demonstraram excelentes atividades antifúngicas contra Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Microsporum gypseun, Trichophyton rubrum e Trichophyton mentagrophytes.

Synthesis, spectral characterization and biological results of new series of 2-(4-pyridyl)-1,2,3,4-tetrahydroquinolines and their closer precursors, -N-aryl-N-[1-(4-pyridyl)but-3-enyl]amines are reported. It was found that both γ-pyridyl substituted precursors and final products, tetrahydroquinolines, showed very good antifungal activities against Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Microsporum gypseun, Trichophyton rubrum and Trichophyton mentagrophytes.

As partes aéreas de seis plantas argentinas - conhecidas geralmente como "botões d'ouro" - são usadas indistintamente na medicina popular ou para obter remédios ervais e fitoterápicos. No entanto, estas entidades pertencem a três gêneros da tribo Helenieae (Asteraceae): Gaillardia, Helenium e Hymenoxys, sendo as espécies mais utilizadas Gaillardia megapotamica var. megapotamica (Spreng.) Bak.; G. megapotamica var. scabiosoides (Arn.) Bak.; G. megapotamica var. radiata (Griseb.) Bak.; Helenium donianum (Hook. & Arn.) Seckt; H. argentinum Ariza e Hymenoxys anthemoides (Juss.) Cass. Neste trabalho, foram estudadas as relações entre os táxons mencionados a partir do ponto de vista morfológico, a sua coexistência em populações naturais e suas ações farmacológicas reputadas. As suas características histológicas são descritas e ilustradas, a fim de obter uma exata identificação botânica dos produtos encontrados no mercado, de forma a garantir a sua qualidade, especialmente porque as amostras são freqüentemente já pulverizadas ou em pó.

The aerial parts of six Argentinean plants - commonly known as "botones de oro"- are indistinctly used either in folk medicine or to obtain herbal remedies and phytotherapics. However, these entities belong to three different genera of the Tribe Helenieae (Asteraceae): Gaillardia, Helenium and Hymenoxys, being the most used species Gaillardia megapotamica var. megapotamica (Spreng.) Bak.; G. megapotamica var. scabiosoides (Arn.) Bak.; G. megapotamica var. radiata (Griseb.) Bak.; Helenium donianum (Hook. & Arn.) Seckt; H. argentinum Ariza and Hymenoxys anthemoides (Juss.) Cass. In this work, we studied the relationships between the mentioned taxa from the morphological point of view, their coexistence in natural populations and their reputed pharmacological actions. Their histological features are described and illustrated, in order to obtain an accurate botanical identification of the products found in the market so as to guarantee their quality, especially because the samples are often already powdered or grounded.

Os extratos em hexano, diclorometano, acetato de etila e etanol das entrecascas de Bowdichia virgilioides, Calophyllum brasiliense, Cariniana rubra, Lafoensia pacari e Stryphnodendron obovatum, do rizoma de Simaba ferruginea e do látex de Croton urucurana foram triados contra um painel de bactérias e fungos usando o método de microdiluição em caldo. O látex de Croton urucurana foi o material derivado de planta com maior atividade antimicrobiana. Os extratos em acetato de etila e hexano da entrecasca de Calophyllum brasiliense destacaram-se por suas seletivas atividades antibacterianas. Os extratos polares da entrecasca de Lafoensia pacari notabilizaram-se por suas potentes e seletivas atividades contra leveduras e os extratos polares e não-polares de Bowdichia virgilioides por suas atividades antifúngicas contra hialo-hifomicetos e dermatófitos. Este é o primeiro relato mostrando atividades antifúngicas para os extratos de Cariniana rubra e Simaba ferruginea. Esse trabalho demonstrou a atividade antimicrobiana de plantas medicinais do Cerrado de Mato Grosso em ensaios in vitro e indica que elas podem ser potenciais candidatas para o desenvolvimento de novas estratégias no tratamento de infecções bacterianas e fúngicas.

Hexane, dichloromethane, ethyl acetate and ethanol extracts from stem barks of Bowdichia virgilioides, Calophyllum brasiliense, Cariniana rubra, Lafoensia pacari, and Stryphnodendron obovatum and rhizome of Simaba ferruginea and Dragon's blood red sap from Croton urucurana were screened against a panel of bacteria and fungi using the micro-broth dilution method. Dragon's blood from Croton urucurana was the most effective antimicrobial plant material. Ethyl acetate and hexane extracts of Calophyllum brasiliense stem bark deserved distinction by their selective antibacterial activity. Lafoensia pacari stem bark polar extracts distinguished by their potent and selective anti-yeast activity and Bowdichia virgilioides polar and non-polar extracts by their antifungal activity towards hyalohypho-mycetes and dermatophytes. This is the first report showing antifungal activity for polar extracts of Cariniana rubra and Simaba ferruginea. This study has demonstrated antimicrobial activity of Mato Grosso Cerrado ethnomedicinal plants in in vitro assays and has indicated that they can be effective potential candidates for the development of new strategies to treat fungal and bacterial infections.