22 research outputs found
Antifungal activity of schinol and a new biphenyl compound isolated from Schinus terebinthifolius against the pathogenic fungus Paracoccidioides brasiliensis
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to isolate and identify the antifungal compounds from the extracts of <it>Schinus terebinthifolius </it>(Anacardiaceae) against clinical isolates of the pathogenic fungus <it>Paracoccidioides brasiliensis</it>.</p> <p>Methods</p> <p>The hexane and dichlomethane fractions from leaves and stems of <it>S. terebinthifolius </it>were fractionated using several chromatography techniques to afford four compounds.</p> <p>Results</p> <p>The compounds isolated from <it>S. terebinthifolius </it>were identified as schinol (<b>1</b>), a new biphenyl compound, namely, 4'-ethyl-4-methyl-2,2',6,6'-tetrahydroxy[1,1'-biphenyl]-4,4'-dicarboxylate (<b>2</b>), quercetin (<b>3</b>), and kaempferol (<b>4</b>). Compounds <b>1 </b>and <b>2 </b>were active against different strains of <it>P. brasiliensis</it>, showing a minimal inhibitory concentration value against the isolate Pb B339 of 15.6 μg/ml. The isolate Pb 1578 was more sensitive to compound <b>1 </b>with a MIC value of 7.5 μg/ml. Schinol presented synergistic effect only when combined with itraconazole. The compounds isolated from S. <it>terebinthifolius </it>were not able to inhibit cell wall synthesis or assembly using the sorbitol assay.</p> <p>Conclusion</p> <p>This work reveals for the first time the occurrence of compound <b>2 </b>and discloses activity of compounds <b>1 </b>and <b>2 </b>against several clinical isolates of <it>P. brasiliensi</it>s. These results justify further studies to clarify the mechanisms of action of these compounds.</p
Volatile compounds of Lamiaceae exhibit a synergistic antibacterial activity with streptomycin
Fingerprint of volatiles from plant extracts based on SPME-GC-MS
The Laboratory of Chemistry of Natural Products has an ex situ collection of extracts from organisms of the biodiversity aiming at bioprospecting. Nowadays the collection has about 4000 extracts from 1000 different species. Extracts are used to identify new bioactive compounds that could be useful for developing new drugs against neglected diseases like leishmaniosis, Chagas disease, malaria and tuberculosis. After biologic assays, the bioactive extracts need to be prepared in larger quantity to allow isolation and characterization of the bioactive component. At this time, it is important to not only confirm the bioactivity of new extract but also check if its composition is similar to the old one. It was evaluated the ability of Solid Phase Microextraction and Gas Chromatography-Mass Spectrometry analysis (SPME-GC-MS). It was used the AMDIS (Automatic Mass Spectral Deconvolution and Identification System) software as tools to collect and to compare the chromatographic profiles of each extract (fingerprint). Forty six samples were analyzed, it was possible to infer from the composition of each sample and common compounds. Nine groups of samples, collected at different time, were analyzed and seasonal modifications between then could be elucidated. The results showed that this methodology can be used to monitor the composition of extracts, allowing to monitor chemical changes that may occur during storage periods and to investigate the occurrence of a determined component in different extracts
Flavonoids from leaves of Mauritia flexuosa
The chromatographic fractionation of the Mauritia flexuosa L. f., Arecaceae, leaves extract, a plant known by the name of buriti palm tree, resulted in the isolation of six flavonoids: tricin-7-O-rutinoside, apigenin-6-C-arabinoside, 8-C-glucoside (isoschaftoside), kaempferol-3-O-rutinoside (nicotiflorine), quercetin-3-O-rutinoside (rutin), luteolin-8-C-glucoside (orientin) and luteolin-6-C-glucoside (isoorientin). The flavonoids were found out and previously reported as constituents of the Arecaceae family plants, but the occurrence of C-glucoside flavonoids, in the species being analyzed, is described for the first time on this study. The structural elucidations of all of the isolated compounds were performed by means of the comparison of their spectral data (1H and 13C NMR, UV and ESI-MS) with those ones of the literature. Keywords: Arecaceae, flavonoids, Mauritia flexuos
Antibiofilm activity of cashew juice pulp against Staphylococcus aureus, high performance liquid chromatography/diode array detection and gas chromatography-mass spectrometry analyses, and interference on antimicrobial drugs
The epidemiology of Staphylococcus aureus infections has evolved in recent years, as this species is a major Gram-positive pathogen associated with healthcare services. The antimicrobial resistance of this species raises an urgent need for new treatment strategies. Fruits play important nutritional and economic roles in society, but their biological and pharmacological features are poorly explored when compared to nonedible parts of plants such as barks and leaves. In this study, we show that the cashew apple juice [cashew juice pulp (CJP)] extract is active against the planktonic cells of S. aureus strains, and for the first time, we show that CJP is also active against S. aureus biofilms. High performance liquid chromatography and gas chromatography-mass spectrometry analyses were conducted to prospect for polyphenols and free carbohydrates, respectively. Cashew apple juice, which is rich in nutrients, is widely consumed in Brazil; therefore, the quality attributes of CJPs were investigated. Samples were evaluated for pH, total titratable acidity, vitamin C levels, and total soluble solids. We also detected an antagonistic interference of CJP when it was combined with different antimicrobial drugs
Changes in the essential oil composition of leaves of Echinodorus macrophyllus exposed to
Leaves of Echinodorus macrophyllus (Kunth) Micheli, Alismataceae, were exposed to different doses of γ-radiation (0.00, 1.00, 3.00, 5.00, 10.00, and 20.00 kGy) and the chemical composition of their essential oils was investigated. The extractive process of the essential oil was more favored when the leaves were irradiated. The essential oil components were identified by correlation between GC-FID data and retention parameters obtained from the Kováts method. Moreover, GC-MS analyses of the essential oils were correlated with fragmentation profiles in the NIST standard mass fragmentation data bank. The essential oil of E. macrophyllus contains biologically active constituents of different chemical classes. Acyclic monoterpenes and sesquiterpenes showed increase in concentration when the leaves were exposed to γ-radiation. On the other hand, the component concentrations of some chemical classes were lightly decreased, i.e., for bicyclic monoterpenes, diterpenes, triterpenes, carboxylic esters, and carotenoid derivatives
Chemical constituents of Habenaria petalodes Lindl. (Orchidaceae)
Habenarioside, a new natural product identified as [(2R)-2-[(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)oxy]-2-(2-methylpropyl)-1,4-dioxo-1,4-butanediyl]bis(oxymethylene-4,1-phenylene) bis-β-D-glucopyranoside, along with two known related metabolites, loroglossin and militarin, were isolated from the ethanol extract of the whole plant Habenaria petalodes Lindl. (Orchidaceae). The flavonoids isoquercitrin, isorhamnetin 3-O-β-D-glucopyranoside, and isorhamnetin 3,7-di-O-β-D-glucopyranoside were also isolated. The structures of all compounds were established by analysis of their MS, IR, UV, 1D and 2D NMR spectra, and comparison with published data
Changes in the essential oil composition of leaves of Echinodorus macrophyllus exposed to γ-radiation
Abstract: Leaves of Echinodorus macrophyllus (Kunth) Micheli, Alismataceae, were exposed to different doses of γ-radiation (0.00, 1.00, 3.00, 5.00, 10.00, and 20.00 kGy) and the chemical composition of their essential oils was investigated. The extractive process of the essential oil was more favored when the leaves were irradiated. The essential oil components were identified by correlation between GC-FID data and retention parameters obtained from the Kováts method. Moreover, GC-MS analyses of the essential oils were correlated with fragmentation profiles in the NIST standard mass fragmentation data bank. The essential oil of E. macrophyllus contains biologically active constituents of different chemical classes. Acyclic monoterpenes and sesquiterpenes showed increase in concentration when the leaves were exposed to γ-radiation. On the other hand, the component concentrations of some chemical classes were lightly decreased, i.e., for bicyclic monoterpenes, diterpenes, triterpenes, carboxylic esters, and carotenoid derivatives
Essential oil of Mitracarpus frigidus as a potent source of bioactive compounds
In our previous work (Fabri et al. 2009), we showed that different extracts of Mitracarpus frigidus had significant antibacterial, antifungal and leishmanicidal activities. In order to increase our knowledge about this species, this work assesses the chemical composition and the in vitro biological activity of its essential oil. Thus, the essential oil obtained by hydrodistillation of the aerial parts of M. frigidus was analyzed by GC/MS. Among several compounds detected, 11 were identified, being linalool and eugenol acetate the major components. The essential oil exhibited a moderate antibacterial effect against Staphyloccocus aureus, Bacillus cereus, Pseudomonas aeruginosa and Enterobacter cloacae (MIC 250 µg/mL). On the other hand, it showed a strong antifungal effect against Cryptoccocus neoformans (MIC 8 µg/mL) and Candida albicans (MIC 63 µg/mL). Expressive activity against L. major and L. amazonensis promastigote forms with IC50 values of 47.2 and 89.7 µg/mL, respectively, were also observed. In addition, the antioxidant activity was investigated through DPPH radical-scavenging and showed a significative activity with IC50 of 38 µg/mL. The cytotoxicity against Artemia salina was moderate with LC50 of 88 µg/mL. The results presented here are the first report on the chemical composition and biological properties of M. frigidus essential oil