Estudo químico das algas pardas Lobophora variegata, Dictyota menstrualis, Dictyota mertensii e investigação farmacológica dos compostos isolados

In this work, the extracts from the algae Lobophora variegata, Dictyota menstrualis and Dictyota mertensii (Phaeophyceae, Dictyotaceae) were investigated, resulting in the isolation of twenty-two compounds. From Dictyota species were isolated diterpenes of different skeletons such as prenilated guai...

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Detalles Bibliográficos
Autor: Ávila, Fábio do Nascimento
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2019
País:Brasil
Institución:Universidade Federal do Ceará (UFC)
Repositorio:Repositório Institucional da Universidade Federal do Ceará (UFC)
Idioma:portugués
OAI Identifier:oai:repositorio.ufc.br:riufc/77957
Acceso en línea:http://repositorio.ufc.br/handle/riufc/77957
Access Level:acceso abierto
Palabra clave:CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA
Lobophora variegata
Dictyota menstrualis
Atividade citotóxica
Atividade antimicrobiana
Cytotoxic activity
Antimicrobial activity
Descripción
Sumario:In this work, the extracts from the algae Lobophora variegata, Dictyota menstrualis and Dictyota mertensii (Phaeophyceae, Dictyotaceae) were investigated, resulting in the isolation of twenty-two compounds. From Dictyota species were isolated diterpenes of different skeletons such as prenilated guaiane and cadinane, crenulidane and dollabelane. Among these compounds, four have been described for the first time. From L. variegata were isolated long-chain alcohol and epoxide, two of which are new compounds. The compounds were isolated using classic methods of chromatography including chromatography on silica gel, sephadex LH-20 and high performance liquid chromatography. The structure elucidation of compounds was performed by spectroscopic methods such as: mass spectrometry (HRESIMS, APCI and GC-MS) and nuclear magnetic resonance (1H and 13C NMR) including bidimensional techniques (COSY, HSQC e HMBC), and comparison with literature data. The isolated compounds were evaluated for their cytotoxicity against the cancer cell line (HCT-116 and RAW-264.7), antimicrobial properties against Gram-positive (S. aureus ATCC 6538P) and Gram-negative (E. coli ATCC 10536) bacteria strains, antioxidant (DPPH) and anti-inflammatory effects. The long-chain epoxides designated as epoxy-lobophorenes A and B (isolated of L. variegata) showed anti-inflammatory and antioxidant effects, while the diterpenes designated dictyols K, M, N and O (isolated of D. menstrualis) showed anti-inflammatory activity comparable to dexamethasone, a potent anti-inflammatory drug in clinical use.