Pyrene degradation by marine-derived ascomycete: process optimization, toxicity, and metabolic analyses.

Marine-derived fungi are relevant genetic resources for bioremediation of saline environments/processes. Among the five fungi recovered from marine sponges able to degrade pyrene (Py) and benzo[a]pyrene (BaP), Tolypocladium sp. strain CBMAI 1346 and Xylaria sp. CBMAI 1464 presented the best removal rates of Py and BaP, respectively. Since the decrease in BaP was related to mycelial adsorption, a combined strategy was applied for the investigation of Py degradation by the fungus Tolypocladium sp. CBMAI 1346. The selected fungus was able to degrade about 95% of Py after 7 days of incubation (optimized conditions), generating metabolites different from the ones found before optimization. Metabolites and transcriptomic data revealed that the degradation occurred mainly by the cytochrome P450 pathway. Putative monooxygenases and dioxygenases found in the transcriptome may play an important role. After 21 days of degradation, no toxicity was found in the optimized culture conditions. The findings from the present study highlight the potential of marine-derived fungi to degrade environmental pollutants and convey innovative information related to the metabolism of pyrene.

In vitro Activities of Pfaffia glomerata Root Extract, Its Hydrolyzed Fractions and Pfaffic Acid Against Trypanosoma cruzi Trypomastigotes.

This article reports on the in vitro activity of the hydroalcoholic extract of Pfaffia glomerata roots, its hydrolyzed fractions, and pfaffic acid against Trypanosoma cruzi. The hydroalcoholic extract obtained from dried, milled P. glomerata roots was submitted to acid hydrolysis followed by partition with CHCl3 . The concentrated CHCl3 fraction was suspended in MeOH/H2 O and partitioned with hexane (F1), CHCl3 (F2), and AcOEt (F3), in this sequence. The trypanocidal activity of the hydrolyzed extract and its fractions was evaluated in vitro. The hydroalcoholic extract displayed low activity, but fraction F1 was active against trypomastigotes of the Y strain of T. cruzi, with IC50 = 47.89 µg/ml. The steroids campesterol (7.7%), stigmasterol (18.7%), ß-sitosterol (16.8%), Δ7 -stigmastenol (4.6%), and Δ7 -spinasterol (7.5%) were the major constituents of F1, along with fatty acid esters (7.6%) and eight aliphatic hydrocarbons (30.1%). Fractions F2 and F3 exhibited moderate activity, and pfaffic acid, one of the main chemical constituents of these fractions, displayed IC50 = 44.78 µm (21.06 µg/ml). On the other hand, the hydroalcoholic extract of P. glomerata roots, which is rich in pfaffosides, was inactive. Therefore, the main aglycone of pfaffosides, pfaffic acid, is much more active against trypomastigotes of the Y strain of T. cruzi than its corresponding glycosides and should be further investigated.

Chemical Characterization and Antimicrobial Activity Evaluation of Natural Oil Nanostructured Emulsions.

The aim of this work was to investigate the antimicrobial activity of nanostructured emulsions based on copaiba (Copaifera langsdorffii) resin-oil, copaiba essential oil, and bullfrog (Rana catesbeiana Shaw) oil against fungi and bacteria related to skin diseases. Firstly, the essential oil was extracted from copaiba resin-oil and these oils, along with bullfrog oil, were characterized by gas chromatography combined with mass spectrometry (GC-MS). Secondly, nanostructured emulsion systems were produced and characterized. The antimicrobial susceptibility assay was performed, followed by the Minimum Inhibitory Concentration (MIC) determination, the bioautography assay, and the antibiofilm determination. Strains of the genera Staphylococcus, Pseudomonas, and Candida were used. The CG-MS analysis was able to identify the components of copaiba resin-oil, copaiba essential oil, and bullfrog oil. The MIC assay in association with the bioautography revealed that some esters of palmitic and oleic acids, a-curcumene, a-himachalene, isothujol, and α-fenchene--probably inhibited some strains. The nanostructured emulsions based on copaiba resin-oil and essential oil improved the antimicrobial activity of the pure oils, especially against Staphylococcus and Candida, resistant to azoles. The bullfrog oil nanostructured emulsion showed a lower antimicrobial effect when compared to the copaiba samples. However, bullfrog oil-based nanostructured emulsion showed a significant antibiofilm activity (p < 0.05). Given the significant antimicrobial and antibiofilm activities of the evaluated oils, it may be concluded that nanostructured emulsions based on copaiba and bullfrog oils are promising candidates for the treatment of infections and also may be used to incorporate other antimicrobial drugs.

Action of essential oils from Brazilian native and exotic medicinal species on oral biofilms.

BACKGROUND: Essential oils (EO) obtained from twenty medicinal and aromatic plants were evaluated for their antimicrobial activity against the oral pathogens Candida albicans, Fusobacterium nucleatum, Porphyromonas gingivalis, Streptococcus sanguis and Streptococcus mitis. METHODS: The antimicrobial activity of the EO was evaluates by microdilution method determining Minimal Inhibitory Concentration. Chemical analysis of the oils compounds was performed by Gas chromatography-mass spectrometry (CG-MS). The most active EO were also investigated as to their actions on the biolfilm formation. RESULTS: The most of the essential oils (EO) presented moderate to strong antimicrobial activity against the oral pathogens (MIC--Minimal Inhibitory Concentrations values between 0.007 and 1.00 mg/mL). The essential oil from Coriandrum sativum inhibited all oral species with MIC values from 0.007 to 0.250 mg/mL, and MBC/MFC (Minimal Bactericidal/Fungicidal Concentrations) from 0.015 to 0.500 mg/mL. On the other hand the essential oil of C. articulatus inhibited 63.96% of S. sanguis biofilm formation. Through Scanning Eletronic Microscopy (SEM) images no changes were observed in cell morphology, despite a decrease in biofilm formation and changes on biofilm structure. Chemical analysis by Gas Chromatography-Mass Spectrometry (GC-MS) of the C. sativum essential oil revealed major compounds derivatives from alcohols and aldehydes, while Cyperus articulatus and Aloysia gratissima (EOs) presented mono and sesquiterpenes. CONCLUSIONS: In conclusion, the crude oil from C. articulatus exhibited the best results of antimicrobial activity e ability to control biofilm formation. The chemical analysis showed the presence of terpenes and monoterpenes such as a-pinene, a-bulnesene and copaene. The reduction of biofilms formation was confirmed from SEM images. The results of this research shows a great potential from the plants studied as new antimicrobial sources.

Anti-inflammatory activity and possible mechanism of extract from Mikania laevigata in carrageenan-induced peritonitis.

OBJECTIVES: The aim was to test the potential use of an extract of Mikania laevigata (popularly known in Brazil as guaco), made from leaves harvested in different months of the year, on neutrophil migration after an inflammatory stimulus and investigate the underlying molecular mechanisms. METHODS: We examined the effect of guaco on vascular permeability and leucocyte function in carrageenan-induced peritonitis in mice. KEY FINDINGS: Our results demonstrated that guaco extract administered subcutaneously (3 mg/kg) decreased the vascular permeability and also leucocyte rolling and adhesion to the inflamed tissues by a mechanism dependent on nitric oxide. Specifically, inhibitors of nitric oxide synthase remarkably abrogated the guaco extract-mediated suppression of neutrophil migration to the inflammatory site. In addition, guaco extract-mediated suppression of neutrophil migration appeared to be dependent on the production of the cytokines interleukin-1beta and tumour necrosis factor-alpha. One of the major constituents of the guaco extract, coumarin, was able to inhibit the neutrophil migration towards the inflammatory focus. CONCLUSIONS: In conclusion the anti-inflammatory effect induced by guaco extract may be by inhibition of pro-inflammatory cytokine production at the inflammatory site.

Effect of Artemisia annua L. leaves essential oil and ethanol extract on behavioral assays / Efeito do extrato etanólico bruto e óleo essencial das folhas de Artemisia annua em modelos comportamentais

Artemisia annua has been used as a traditional plant for the treatment of malaria and fever in China because of the presence of its active compound, artemisinin. The present study evaluated the central activity of the essential oil and the crude ethanol extract of A. annua L. in animals as a part of a psychopharmacological screening of this plant. The extract was prepared in ethanol (AEE) and the essential oil (AEO) obtained by hydrodistillation, both with fresh leaves. Induced immobility, the forced swimming test (FST) and the open-field test (OFT) are well-known animal models to study drug-induced depression. The administration of A. annua essential oil or crude ethanol extract increased the immobility time in the FST and decreased other activities (ambulation, exploration, rearing and grooming) in the OFT in animals. Both AEO and AEE prolonged pentobarbital-induced sleep as well, but the essential oil had a marked effect. Observing these results, it is possible to suggest that A. annua crude ethanol extract and essential oil could act as depressors on the Central Nervous System (CNS).

Artemisia annua tem sido utilizada tradicionalmente para o tratamento de malária e febre na China devido à presença do princípio ativo, artemisinina. O presente trabalho avaliou a atividade central de do óleo essencial obtido por hidrodestilação e do extrato etanólico bruto de folhas frescas de A. annua em modelo in vivo como parte de um screening farmacológico dessa espécie. Sono induzido por pentobarbital, nado forçado e o ensaio de campo aberto são modelos de estudo conhecidos para o estudo de fármacos sobre depressão induzida. A administração do óleo essencial ou extrato bruto etanólico de A. annua aumentaram o tempo de imobilidade no teste do nado forçado. Por outro lado, diminuíram outros parâmetros no campo aberto, como ambulação, exploração, o ato de lamber as patas ou se lamber. Ambos produtos aumentaram o tempo de sono induzido por pentobarbital, com o óleo essencial apresentando um efeito superior ao do extrato. Pela análise dos resultados, é possível sugerir que tanto o extrato bem como o óleo essencial podem atuar como depressores do Sistema Nervoso Central (SNC).

The influence of a novel propolis on mutans streptococci biofilms and caries development in rats.

A flavonoids-free Brazilian propolis (type 6) showed biological effects against mutans streptococci and inhibited the activity of glucosyltransferases. This study evaluated the influence of the ethanolic extract of a novel type of propolis (EEP) and its purified hexane fraction (EEH) on mutans streptococci biofilms and the development of dental caries in rats. The chemical composition of the propolis extracts were examined by gas chromatography/mass spectrometry. The effects of EEP and EEH on Streptococcus mutans UA159 and Streptococcus sobrinus 6715 biofilms were analysed by time-kill and glycolytic pH drop assays. Their influence on proton-translocating F-ATPase activity was also tested. In the animal study, the rats were infected with S. sobrinus 6715 and fed with cariogenic diet 2000. The rats were treated topically twice a day with each of the extracts (or control) for 5 weeks. After the experimental period, the microbial composition of their dental plaque and their caries scores were determined. The results showed that fatty acids (oleic, palmitic, linoleic and stearic) were the main compounds identified in EEP and EEH. These extracts did not show major effects on the viability of mutans streptococci biofilms. However, EEP and EEH significantly reduced acid production by the biofilms and also inhibited the activity of F-ATPase (60-65%). Furthermore, both extracts significantly reduced the incidence of smooth surface caries in vivo without displaying a reduction of the percentage of S. sobriuns in the animals' plaque (P < 0.05). However, only EEH was able to reduce the incidence and severity of sulcal surface caries (P < 0.05). The data suggest that the cariostatic properties of propolis type 6 are related to its effect on acid production and acid tolerance of cariogenic streptococci; the biological activities may be attributed to its high content of fatty acids.