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Alzheimer's disease (AD) is a multifactorial health problem widespread over the world. Regarding the historical importance of the alkaloids in the central nervous system pharmacology they remain as promising drug candidates against AD. Seven alkaloids from Amaryllidaceae and Fabaceae were evaluated in vivo, in vitro and in silico targets related to the AD pathophysiology. Erythraline and erysodine showed the greatest potential compared to Memantine, a drug currently used in AD therapy, by delaying the Aß1-42-induced paralysis in the transgenic strain CL2006 Caenorhabditis elegans, an alternative model to assess the impairment of beta-amyloid peptide deposition. The in vitro inhibition of the acetylcholinesterase was observed for the first time for Erythrina alkaloids; however Lycorine was the most active. Docking simulation contributed to comprehend this potential by showing a hydrophobic interaction between acetylcholinesterase and Lycorine in the amino acid residue TRP 84 as well as hydrogen bonds with TRY 121 and ASP 72.

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Astaxanthin (ASTA) is a ketocarotenoid found in many marine organisms and that affords many benefits to human health. ASTA is particularly effective against radical-mediated lipid peroxidation, and recent findings hypothesize a "mitochondrial-targeted" action of ASTA in cells. Therefore, we examined the protective effects of ASTA against lipid peroxidation in zwitterionic phosphatidylcholine liposomes (PCLs) and anionic phosphatidylcholine: phosphatidylglycerol liposomes (PCPGLs), at different pHs (6.2 to 8.0), which were challenged by oxidizing/nitrating conditions that mimic the regular and preapoptotic redox environment of active mitochondria. Pre-apoptotic conditions were created by oxidized/nitr(osyl)ated cytochrome c and resulted in the highest levels of lipoperoxidation in both PCL and PCPGLs (pH 7.4). ASTA was less protective at acidic conditions, especially in anionic PCPGLs. Our data demonstrated the ability of ASTA to hamper oxidative and nitrative events that lead to cytochrome c-peroxidase apoptosis and lipid peroxidation, although its efficiency changes with pH and lipid composition of membranes.

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RATIONALE: Carotenoids are polyene isoprenoids with an important role in photosynthesis and photoprotection. Their characterization in biological matrices is a crucial subject for biochemical research. In this work we report the full fragmentation of 16 polyenes (carotenes and xanthophylls) by electrospray ionization tandem mass spectrometry (ESI-CID-MS/MS) and nanospray tandem mass spectrometry (nanoESI-CID-MS/MS). METHODS: Analyses were carried out on a quadrupole time-of-flight (QTOF) mass spectrometer coupled with a nanoESI source and on a Fourier transform ion cyclotron resonance (FTICR) mass spectrometer with an ESI source. The formulae of the product ions were determined by accurate-mass measurements. RESULTS: It is demonstrated that the fragmentation routes observed for the protonated carotenoids derive essentially from charge-remote fragmentations and pericyclic rearrangements, such as electrocyclic and retro-ene eliminations (assisted or not by a sigmatropic hydrogen shift). All mechanisms are dependent on cis-trans isomerization through the formation of several conjugated polyene carbocation intermediates. Some specific ions for the carotenoid epoxides were justified through formation of cyclic oxonium ions. CONCLUSIONS: Complete fragmentation pathways of protonated carotenoids by ESI- and nanoESI-CID-MS/MS provided structural information about functional groups, polyene chain and double bonds, and contribute to identification of carotenoids based on MS/MS fragmentation patterns. Copyright © 2016 John Wiley & Sons, Ltd.

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CONTEXT: The aerial parts of Sphagneticola trilobata (L.) Pruski (Asteraceae) are popularly used to treat topical inflammation, but have not been fully investigated. OBJECTIVE: To identify polar compounds in S. trilobata extracts and develop a new topical phytomedicine based on the kaurenoic acid (KA) content while monitoring and demonstrating its topical anti-inflammatory activity. MATERIALS AND METHODS: Ethanol spray-dried extract of S. trilobata was analysed by LC-MS while the KA content from semisolid was analysed by LC-UV. The extent of ear edema induced by applying 20 µL of croton oil (2.5%), arachidonic acid (AA; 2 mg/ear) and decanoylphorbol-13-acetate (TPA; 2.5 mg/ear) in mice was used to evaluate the biological activity of the semisolids, which were applied 30 min before the phlogistic agents. RESULTS: Eight phenylpropanoids and four oleanane-type triterpenoid saponins were identified, majority of them reported for the first time in this species, in addition to KA. The semisolid containing 1.0% of dried extract reduced the ear edema induced by croton oil [77.2 ± 4.5%; ID50 = 0.49 (0.28-0.87%)], TPA (81.5 ± 2.4%) and AA (39.1 ± 6.9%), with decreasing effect at higher KA concentrations. This was accompanied by neutrophil migration inhibition as investigated by biochemical and histological assays. DISCUSSION AND CONCLUSION: The anti-inflammatory effects were (at least in part) due to the interference in protein kinase C (PKC) activation, AA-cascade products and neutrophil migration inhibition, demonstrating the efficacy of the folk topical usage of this plant. The results support the development of a novel topical anti-inflammatory phytomedicine properly standardized to treat inflammatory dermatological diseases.

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Leishmaniasis is one of the World's most problematic diseases in developing countries. Traditional medicines to treat leishmaniasis have serious side effects, as well as significant parasite resistance problems. In this work, two alkaloids 1 and 2 were obtained from Corydalis govaniana Wall and seven alkaloids 3-9, were obtained from Erythrina verna. The structures of the compounds were confirmed by mass spectrometry and 1D- and 2D-NMR spectroscopy. The leishmanicidal activity of compounds 1-9 against Leishmania amazonensis was tested on promastigote forms and cytotoxicity against J774 (macrophage cell line) was assessed in vitro. Compound 1 showed potent activity (IC50 = 0.18 µg/mL), compared with the standard amphotericin B (IC50 = 0.20 µg/mL). The spirocyclic erythrina-alkaloids showed lower leishmanicidal activity than dibenzoquinolizine type alkaloids.

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BACKGROUND: Erythrina verna, popularly known as "mulungu", is a Brazilian medicinal plant used to treat anxiety. Erythrina alkaloids have been described in several species of Erythrina, which have biological and therapeutic properties well known that include anxiolytic and sedative effects. METHODS: In this work, in vitro metabolism of erythraline (1), the major spirocyclic alkaloid of Erythrina verna, was studied in the pig cecum model and by biomimetic phase I reactions. The biomimetic reactions were performed with Jacobsen catalyst to produce oxidative metabolites and one metabolite was isolated and evaluated against cancer cells, as HL-60 (promyelocytic leukemia), SF-295 (Glioblastoma) and OVCAR-8 (ovarian carcinoma). RESULTS: Erythraline exhibited no metabolization by the pig microbiota and a main putative metabolite was formed in a biomimetic model using Jacobsen catalyst. This metabolite was isolated and identified as 8-oxo-erythraline (2). Finally, erythraline and the putative metabolite were tested in MTT model and both compounds showed no important cytotoxic activity against tumor cells. CONCLUSIONS: The alkaloid erythraline was not metabolized by intestinal microbiota, but it was possible to identify its oxidative metabolite from biomimetic reactions. So these data are interesting and stimulate other studies involving this alkaloid, since it is present in phytomedicine products and there are not reported data about the metabolism of erythrina alkaloids.

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Gracilaria domingensis (Kützing) Sonder ex Dickie and Gracilaria birdiae (Plastino & Oliveira) (Gracilariales, Rhodophyta) are seaweeds that occur on the Brazilian coast. Based on their economic and pharmaceutical importance, we investigated the antioxidant activity of the methanolic, ethyl acetate and hexane extracts of both species. The hexane extracts display a high antioxidant activity and comparative analyses indicated G. birdiae as the most active species. Chemical investigation of these fractions showed several carotenoids and fatty acids, as well as cholesterol and sitosterol derivatives. HPLC-DAD analysis of G. birdiae showed violaxanthin (0.04 μg.mg-1 of dry material), antheraxanthin (5.31 μg.mg-1), aloxanthin (0.09 μg.mg-1), zeaxanthin (0.45 μg.mg-1) and β-carotene (0.37 μg.mg-1) as the major carotenoids. G. domingensis showed a similar carotenoid profile, however, with much lower concentration than G. birdiae. Gas chromatography coupled to mass spectrometry was used to determine other nonpolar compounds of these seaweeds. The main compounds detected in both studied species were the fatty acids 16:0; 18:1 Δ9; 20:3 Δ6,9,12, 20:4 Δ5,8,11,14. We found no specificity of compounds in either species. However, G. birdiae, presented higher contents of carotenoids and arachidonic acid than G. domingensis.

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SRTXRF WAS USED TO DETERMINE AS, BA, BR, CA, CO, CR, CS, CU, DY, FE, K, MN, MO, NI, PB, RB, SR, TI, V, AND ZN IN ELEVEN SEAWEED SPECIES COMMONLY FOUND IN FERNANDO DE NORONHA: Caulerpa verticillata (J. Agardh) (Chlorophyta), Asparagopsis taxiformis (Delile), Dictyurus occidentalis (J. Agardh), Galaxaura rugosa (J. Ellis & Solander) J. V. Lamouroux, G. obtusata (J. Ellis & Solander) J. V. Lamouroux, G. marginata (J. Ellis & Solander) J. V. Lamouroux (Rhodophyta), Dictyota cervicornis (Kützing), Dictyopteris justii (J. V. Lamouroux), Dictyopteris plagiogramma (Montagne) Vickers, Padina gymnospora (Kützing) Sonder, and a Sargassum sp. (Phaeophyta). Data obtained were compared to those from the analysis of other parts of the world seaweeds using different analytical techniques and were found to be in general agreement in terms of major and minor elemental components. Results provide baseline information about the absorption and accumulation of these elements by macroalgae in the area.