Currently multiresistant Staphylococcus aureus is one common cause of infections with high rates of morbidity and mortality worldwide, which directs scientific endeavors in search for novel antimicrobials. In this study, nine extracts from Bidens pilosa (root, stem, flower and leaves) and Annona crassiflora (rind fruit, stem, leaves, seed and pulp) were obtained with ethanol: water (7:3, v/v) and their in vitro antibacterial activity evaluated through both the agar diffusion and broth microdilution methods against 60 Oxacillin Resistant S. aureus (ORSA) strains and against S. aureus ATCC6538. The extracts from B. pilosa and A. crassiflora inhibited the growth of the ORSA isolates in both methods. Leaves of B. pilosa presented mean of the inhibition zone diameters significantly higher than chlorexidine 0.12% against ORSA, and the extracts were more active against S. aureus ATCC (p < 0.05). Parallel, toxicity testing by using MTT method and phytochemical screening were assessed, and three extracts (B. pilosa, root and leaf, and A. crassiflora, seed) did not evidence toxicity. On the other hand, the cytotoxic concentrations (CC50 and CC90) for other extracts ranged from 2.06 to 10.77 mg/mL. The presence of variable alkaloids, flavonoids, tannins and saponins was observed, even though there was a total absence of anthraquinones. Thus, the extracts from the leaves of B. pilosa revealed good anti-ORSA activity and did not exhibit toxicity.

No abstract

P. edulis infusion presented antinociceptive and anti-inflammatory activities in all experiments realized in this study, which could be related to the presence of triterpenoids and flavonoids. These results provide scientific support for the traditional use of this species in the management of pain and inflammation.

No abstract

RESUMO:Syzygium jambos (L.) Alston, Myrtaceae, é empregado na medicina popular como digestivo e antiinflamatório. A triagem fitoquímica da droga pulverizada (folhas) indicou a presença de flavonóides, taninos e óleo volátil. O extrato hidroetanólico a 70% das folhas de S. jambos foi preparado por percolação e liofilizado. O conteúdo de taninos das folhas e do extrato foi calculado, respectivamente, em 21,9% e 43,3%. O teor de flavonóides foi de 0,6% (folhas) e 1,2% (extrato). A administração oral prévia do extrato (400 mg/kg) a ratos Wistar reduziu significativamente as lesões gástricas induzidas por etanol acidificado. No modelo de úlcera subcrônica, com indução de lesão gástrica utilizando ácido acético a 30%, o tratamento com o extrato (400 mg/kg) não apresentou resultado significativo. A atividade antioxidante do extrato foi avaliada através dos modelos de lipoperoxidação e de medida de capacidade seqüestrante de radicais DPPH. Os valores obtidos de Q 1/2 (MDA) e CE 50 (DPPH) foram, respectivamente, 0,17 mg/mL e 5,68 mg/mL.Unitermos: Syzygium jambos, Myrtaceae, atividade antiúlcera, atividade antioxidante.ABSTRACT: "Antiulcerogenic and antioxidant activities of leaf extract of Syzygium jambos (L.) Alston (Myrtaceae)". Syzygium jambos (L.) Alston, Myrtaceae, is commonly employed in folk medicine as digestive and anti-inflammatory. Phytochemical screening of the powdered dried leaves indicates the presence of flavonoids, tannins and essential oil. Hydroethanol extracts (70%) were prepared by percolation and freeze-drying. The tannin content of dried leaves and extract was, respectively, 21.9% and 43.3%. The flavonoid content was 0.6% (dried leaves) and 1.2% (extract). Previous oral administration of S. jambos leaves extract (400 mg/kg) to rats reduced significantly gastric injury induced by HCl/ethanol. At the subcronic ulcer model by induction with 30% acetic acid the results were not significant. In vitro antioxidant activity of S. jambos extract was evaluated by malondialdehyde (MDA) and DPPH free radical method. The Q 1/2 for MDA assay was 0.17 mg/mL and the EC 50 for DPPH assay was 5.68 mg/mL.

No abstract

por todo o apoio e orientação. À Profa. Dra. Sílvia Berlanga de Moraes Barros pela colaboração na realização do ensaio antioxidante. Às Professoras Doutoras Mitsuko Taba Ohara e Telma Mary Kaneko pela disponibilização do laboratório para execução do ensaio antimicrobiano. À Dra. Lúcia Rossi pela identificação da espécie. A todos os trindadeiros, que me auxiliaram e abriram seus quintais para a coleta. Especial agradecimento para Clara Rosa de Jesus (Dona Clara) e Júlia Rosa da Apresentação (Vó Júlia) pelas histórias, prosa e graça.

ABSTRACT. The objective of this study was to investigate the antifungal activity of Aloe arborescens dry extract against Trichosporon genus yeast species. Extraction was carried out by means of a longitudinal incision in fresh leaves, which were collected on a vat, and the total volume was frozen and subsequently lyophilized. Then, 40 mg of the dry extract was dissolved in DMSO by gentle inversion in order to obtain a solution whose concentration was 4000 μg mL -1 . This solution became limpid and slightly yellowish because the pigment of the latex was attenuated. It was performed serial dilutions from 2,000 to 15.625 μg mL -1 with RPMI-1640 broth. There was already no pigment in the first dilution of 2000 μg mL -1. It was analyzed fifteen strains of Trichosporon spp., and Candida albicans ATCC 10231 was used as control strain. We carried out the reading of microplates in the ELISA reader device at a wavelength of 530 nm, after incubation for 24 and 48 hours, and it was determinated the Minimum Inhibitory Concentration (MIC). The MIC 50 value obtained for all Trichosporon species and for C. albicans was 500 μg mL -1. As a result, we concluded that Aloe arborescens dry extract has antifungal activity against Trichosporon yeasts.