DEFAR - Departamento de Farmácia
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/530
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Resultados da Pesquisa
Item Himatanthus bracteatus stem extracts present antiflavivirus activity while an isolated sesquiterpene glucoside present only anti-Zika virus activity in vitro.(2019) Silva, Marlene Lourenço da; Stehmann, João Renato; Serafim, Mateus Sá Magalhães; Vale, Valdicley Vieira; Gontijo, Douglas da Costa; Brandão, Geraldo Célio; Kroon, Erna Geessien; Oliveira, Alaíde Braga deThe hexane and ethanol extracts from Himatanthus bracteatus (Apocynaceae) stems were evaluated for antiviral activity against Zika virus, yellow fever virus and dengue virus 2 and for cytotoxicity in Vero cells by MTT assay. The ethanol extract showed good antiviral activity against the three viruses with selective indexes (SI) > 10 and its fractionation led to the isolation of the known plumieride that was active only against Zika virus (SI of 15.97).Item Antiviral activity of Fridericia formosa (Bureau) L. G. Lohmann (Bignoniaceae) extracts and constituents.(2017) Brandão, Geraldo Célio; Kroon, Erna Geessien; Souza Filho, José Dias de; Oliveira, Alaíde Braga deA phytochemical study of Fridericia formosa (Bignoniaceae) ethanol extracts of leaves, stems, and fruits was guided by in vitro assays against vaccinia virus Western Reserve (VACV-WR), human herpes virus 1 (HSV-1), murine encephalomyocarditis virus (EMCV), and dengue virus type 2 (DENV-2) by the MTT method. All the ethanol extracts were active against DENV-2, HSV-1, and VACV-WRwith best results for the fruits extract against DENV-2 (SI > 38.2). For VACV-WRand HSV-1, EC50 values > 200 𝜇g mL−1 were determined, while no inhibition of the cytopathic effect was observed with EMCV. Five compounds were isolated and identified as the C-glucosylxanthones mangiferin (1), 2-O-trans-caffeoylmangiferin (2), 2-O-trans-coumaroylmangiferin (3), 2- O-trans-cinnamoylmangiferin (5), and the flavonoid chrysin (4). The most active compound was 2-O-trans-coumaroylmangiferin (3) with SI > 121.9 against DENV-2 and 108.7 for HSV-1. These results indicate that mangiferin cinnamoyl esters might be potential antiviral drugs.Item Chemistry and antiviral activity of Arrabidaea pulchra (Bignoniaceae).(2013) Brandão, Geraldo Célio; Kroon, Erna Geessien; Souza, Danielle E. R.; Souza Filho, José Dias de; Oliveira, Alaíde Braga deThe aim of the present work was to carry out a bioguided isolation of antiviral chemical constituents from an ethanol extract of leaves from Arrabidaea pulchra (Cham.) Sandwith (EEAPL) that had shown in vitro activity in a previous screening using DNA and RNA viruses. The activity of EEPAL was evaluated against the DNA viruses Human herpesvirus 1 (HSV-1) and Vaccinia virus Western Reserve (VACV-WR) as well as against the RNA viruses Murine encephalomyocarditis virus (EMCV), and Dengue virus 2 (DENV-2) by the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) colorimetric assay. Cytotoxicity was determined in LLCMK2 and Vero cells and the Selectivity Indexes (SI) were calculated. The most potent effect was observed against DENV-2 (EC50 46.8 ± 1.6 μg mL−1; SI 2.7). For HSV-1 and VACV-WR EC50 values > 200 μg mL−1 were determined, while no inhibition of the cytopathic effect was observed with EMCV. Bioguided fractionation of EEAPL by partition between immiscible solvents followed by chromatography over a Sephadex LH20 column afforded two arylpropanoid glycosides, verbascoside (AP 1) and caffeoylcalleryanin (AP 2), along with a terpenoid, ursolic acid (AP 3). AP 1 and AP 3 exhibited similar anti-DENV-2 profiles, with SI values of 3.8 and 3.1, respectively, while AP 2 was the most effective anti-DENV-2 constituent, with a SI of 20.0. Our results show that A. pulchra leaves ethanol extract (EEAPL) affords compounds with antiviral activity, mainly against DENV-2.