207 research outputs found
Banisteriopsis Species: A Source of Bioactive of Potential Medical Application
In recent years, interest in further development of herbal or botanical drug products derived from traditional preparations has been increasing steadily. Plants have been used for thousands of years to treat health disorders and to prevent diseases including epidemics. Several research works have been developed to search for new natural products to be used in pharmaceutical products. Active compounds produced during secondary metabolism are responsible for the biological properties of the plant species and may be used to most diverse purposes, including treatment of several diseases. Banisteriopsis species has been described showing interesting activities by its use in popular medicine. The mainly use was described to production of the Ayahuasca, an Amazonian psychotropic plant tea obtained from Banisteriopsis caapi, which contains betacarboline alkaloids, mainly harmine, harmaline and tetrahydroharmine. Other species of Banisteriopsis genus have been described with biological metabolites as antimicrobial, anticholinesterase, antianxiety and others. These biological activities were described chiefly by the presence of alkaloids, flavonoids, tannins. Thus, to stimulate the study into the Banisteriopsis genus, the purpose of the present review is to gather information on the use of the extracts and metabolites of Banisteriopsis species (Malpighiaceae) as a resource to diseases treatment or to pharmaceutical purposes
Austin, dehydroaustin and other metabolites from Penicillium brasilianum
A culture of P. brasilianum, isolated from soil collected at the Serra do Cipó National Park, in Minas Gerais State (Brazil), was grown for 25 days on a dextrose-peptone-salts medium. The corresponding ethylacetate extract was column chromatographed and four compounds were isolated: austin, dehydroaustin, D-mannitol and penicillic acid. This is, in the best of our knowledge, the first time that the meroterpenes austin and dehydroaustin have been isolated from this species. Activity of the extract and isolated compounds was tested against six bacteria and for acetylcholinesterase inhibition. Penicillic acid showed high activity in both tests
Biotransformation of digitoxigenin by Cochliobolus lunatus
The biotransformation of digitoxigenin (1) by Cochliobolus lunatus was investigated. The biotransformation reaction was carried out in a 4-day process, resulting in the isolation of four products, whose structures were elucidated as 1beta-hydroxydigitoxigenin (2), 7beta-hydroxydigitoxigenin (3), 8beta-hydroxydigitoxigenin (4) and digitoxigenone (5). The production of these derivatives under the employed conditions has never been described so far. This is also the first report on the production of compound 4 by a biotransformation reaction
Evaluation of the bactericidal and trypanocidal activities of triterpenes isolated from the leaves, stems, and flowers of Lychnophora pinaster
Preparation and activity of diterpenoids against trypomastigotes of Trypanosoma cruzi
A systematic investigation on the trypanocidal effect of several natural products isolated from Brazilian plant species has been carried out. In this paper we report on the results obtained from the screening of 26 diterpenes from natural sources or of synthetic/microbial transformations origin (mainly derivatives of kaurenoic acid) against trypomastigote forms of Trypanosoma cruzi, the causative agent of Chagas'disease. In the in vitro assays, kaurenoic acid, kaurenol, acutifloric acid and stemodin showed a complete elimination of parasites from the blood. Therefore, such diterpenoids can be considered as starting materials for molecular modification in the search for lead compounds for clearance of infected blood to be used in transfusions. Blood previously treated with active compounds was submitted to an infectivity test. Samples proceeded from treatment with kaurenol and kaurenoic acid showed to be completly clean from T. cruzi as no infection was observed in mice inoculated with contaminated blood treated by these compounds
Novel Derivatives of Kaurenoic Acid: Preparation and Evaluation of their Trypanocidal Activity
O ácido caurenóico, um diterpeno caurânico, mostrou-se ativo in vitro contra formas tripomastigotas do Trypanosoma cruzi. Uma ação lítica sobre os eritrócitos foi uma das limitações encontradas para esta atividade. A síntese de doze derivados deste ácido: quatro amidas, quatro aminas (e três cloridratos) e quatro oximas foi realizada, com o objetivo de se tentar diminuir ou eliminar esse efeito secundário e, se possível, aumentar a atividade em relação ao material de partida. Dentre esses compostos, um mostrou-se mais ativo que o ácido caurenóico, mas também apresentou lise discreta de eritrócitos; outro não apresentou este efeito, mas a atividade não foi aumentada em relação àquela apresentada pelo ácido caurenóico. Kaurenoic acid, a kauranic diterpenoid, presents in vitro activity against trypomastigote forms of Trypanosoma cruzi, showing, however, lytic activity on blood erythrocytes, as a side effect. The syntheses of twelve new derivatives of kaurenoic acid, four amides, four amines (and three hydroclorides) and four oximes, was carried out aiming at the improvement of the therapeutic activity and without the side effect. Among the derivatives prepared, one compound showed enhanced trypanocidal activity in vitro towards Trypanosoma cruzi trypomastigote erythrocytic forms, when compared to kaurenoic acid, but continued to show discrete lytic activity on erythrocytes; another compound showed a level of activity similar to that of kaurenoic acid, but without lysis
Synthesis, Fungitoxic Activity against Botrytis cinerea and Phytotoxicity of Alkoxyclovanols and Alkoxyisocaryolanols
Clovane and isocaryolane derivatives have been proven to show several levels of activity against the phytopathogenic fungus Botrytis cinerea. Both classes of sesquiterpenes are reminiscent of biosynthetic intermediates of botrydial, a virulence factor of B. cinerea. Further development of both classes of antifungal agent requires exploration of the structure-activity relationships for the antifungal effects on B. cinerea and phytotoxic effects on a model crop. In this paper, we report on the preparation of a series of alkoxy-clovane and -isocaryolane derivatives, some of them described here for the first time (2b, 2d, 2f-2h, and 4c-4e); the evaluation of their antifungal properties against B. cinerea, and their phytotoxic activites on the germination of seeds and the growth of radicles and shoots of Lactuca sativa (lettuce). Both classes of compound show a correlation of antifungal activity with the nature of side chains, with the best activity against B. cinerea for 2d, 2h, 4c and 4d. In general terms, while 2-alkoxyclovan-9-ols (2a-2e) exert a general phytotoxic effect, this is not the case for 2-arylalkoxyclovan-9-ols (2f-2i) and 8-alkoxyisocaryolan-9-ols (4a-4d), where stimulating effects would make them suitable candidates for application to plants.This research was supported by a grant from Ministerio de Ciencia, Innovacion y Universidades (RTI2018-097356-B-C21, MCIU/AEI/FEDER, EU). A.d.A.P.B., G.G.d.S. and J.A.T. thank Coordenacao de Aperfeicoamento de Pessoal de nivel superior (CAPES, Brazil) for research fellowships (CAPES-DGU 197/09)
N(4)-tolyl-2-benzoylpyridine thiosemicarbazones and their copper(II) complexes with significant antifungal activity: crystal structure of N(4)-para-tolyl-2-benzoylpyridine thiosemicarbazone
A multi-decade record of high quality fCO2 data in version 3 of the Surface Ocean CO2 Atlas (SOCAT)
The Surface Ocean CO2 Atlas (SOCAT) is a synthesis of quality-controlled fCO2 (fugacity of carbon dioxide) values for the global surface oceans and coastal seas with regular updates. Version 3 of SOCAT has 14.7 million fCO2 values from 3646 data sets covering the years 1957 to 2014. This latest version has an additional 4.6 million fCO2 values relative to version 2 and extends the record from 2011 to 2014. Version 3 also significantly increases the data availability for 2005 to 2013. SOCAT has an average of approximately 1.2 million surface water fCO2 values per year for the years 2006 to 2012. Quality and documentation of the data has improved. A new feature is the data set quality control (QC) flag of E for data from alternative sensors and platforms. The accuracy of surface water fCO2 has been defined for all data set QC flags. Automated range checking has been carried out for all data sets during their upload into SOCAT. The upgrade of the interactive Data Set Viewer (previously known as the Cruise Data Viewer) allows better interrogation of the SOCAT data collection and rapid creation of high-quality figures for scientific presentations. Automated data upload has been launched for version 4 and will enable more frequent SOCAT releases in the future. High-profile scientific applications of SOCAT include quantification of the ocean sink for atmospheric carbon dioxide and its long-term variation, detection of ocean acidification, as well as evaluation of coupled-climate and ocean-only biogeochemical models. Users of SOCAT data products are urged to acknowledge the contribution of data providers, as stated in the SOCAT Fair Data Use Statement. This ESSD (Earth System Science Data) “living data” publication documents the methods and data sets used for the assembly of this new version of the SOCAT data collection and compares these with those used for earlier versions of the data collection (Pfeil et al., 2013; Sabine et al., 2013; Bakker et al., 2014). Individual data set files, included in the synthesis product, can be downloaded here: doi:10.1594/PANGAEA.849770. The gridded products are available here: doi:10.3334/CDIAC/OTG.SOCAT_V3_GRID
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