The endophytic fungus Microsphaeropsis arundinis was isolated from the capitula of the tropical plant Paepalanthus planifolius (Eriocaulaceae). The fungus was cultivated in seven different media, and the ethyl acetate extracts were tested against tumor cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide MTT assay. The culture was scaled up using parboiled rice medium, and the crude extract was purified by classical chromatographic analyses, leading to the isolation of seven compounds. The seven compounds isolated from the culture media included a new aromatic polyketide (1) and other known metabolites. The structures of all the compounds were elucidated by 1D and 2D nuclear magnetic resonance (NMR) and high resolution mass spectrometry (HRMS) analyses. An evaluation of the cytotoxicity of all the isolated compounds showed that these compounds exhibit less activity in comparison with the extract cultured in parboiled rice.

The chemical investigation of ethyl acetate extract from Paepalanthus planifolius capitula resulted in the identification of 1H-naphtho[2,3-c]pyran-1-one,9-[(6-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy]-3,4-dihydro-10-hydroxy-7-methoxy-3-methyl, semi-vioxanthin 9-O-β-D-glucopyranoside, toralactone-9-O-β-D-glucopyranoside, paepalantine-9-O-β-D-glucopyranoside, semi-vioxanthin, 1H-naphtho[2,3-c]pyran-1-one,3,4-dihydro-9,10-dihydroxy-5,7-dimethoxy-3-methyl, vioxanthin and paepalantine dimer, and also the isolation and identification of a new naphthopyranone dimer named planifoliusin A. The chemical structures of two compounds were elucidated by performing spectroscopic 1D and 2D nuclear magnetic resonance (NMR) experiments and spectrometric HRMS (high-resolution mass spectrometry) analysis. Other six naphthopyranone dimers were proposed by MS fragmentation patterns. The minimum inhibitory concentration (MIC) values for vioxanthin (7.8 µg mL-1), planifoliusin A (15.6 µg mL-1) and the ethyl acetate extract (31.2 µg mL-1) showed antimicrobial activity against Staphylococcus aureus (ATCC 25923).

The screening for antimicrobial activity of twenty five endophytic fungi isolated from the aerial parts of Paepalanthus chiquitensis (Eriocaulaceae) was assayed against the bacteria Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli and Salmonella setubal, and the yeast fluconazole-resistant Candida albicans. The ethyl acetate extract produced by Fusarium fujikuroi was the most bioactive and this fungus was chosen for the chemical study, affording the isolation of an alkaloid 2-(4-butylpicolinamide) acetic acid and three known metabolites: fusaric acid, indole acetic acid and the sesterterpene terpestacin. The minimal inhibitory concentration of the extract and of fusaric acid and indole acetic acid for all the tested microorganisms had values from 125 to 1000 µg mL-1.

In this study, fifteen endophytic fungi were isolated from Paepalanthus planifolius (Eriocaulaceae). From the capitula, seven endophytes were screened and evaluated for their metabolomic profile and radical scavenging activity (2,2-diphenyl-1-picrylhydrazyl (DPPH) assay). Chemical investigation of ethyl acetate extract of the endophytic fungus Anthostomella brabeji resulted in the isolation of one new compound, (+)-(6R*,7S*,8R*)-6,7,8-trihydroxy-2,2-dimethyl-5,6,7,8-tetrahydro-chroman-4-one, and three known compounds: 6-hydroxy-2,2-dimethyl-5,6,7,8-tetrahydro-7,8-epoxycroman-4-one, siccayne and eutypinol. All of the compound structures were elucidated using 1D and 2D nuclear magnetic resonance (NMR) and mass spectrometry (MS) analyses. The antimicrobial activity of the compounds and A. brabeji extract were assayed against the microorganisms Staphylococcus aureus, Escherichia coli, Salmonella setubal and Candida albicans. Measured minimal inhibitory concentration (MIC) values ranged from 31.25 to 1000.0 µg mL-1.

This article describes the isolation and identification of flavonoids in the hydroethanolic extract of the aerial parts from Tonina fluviatilis and evaluation of their antiradical activity. A method based on HPLC-DAD was developed and validated for detecting and quantifying flavonoids in hydroethanolic extracts. The flavonoids identified and quantified in the extract were 6,7-dimethoxyquercetin-3-O-β-D-glucopyranoside (1), 6-hydroxy-7-methoxyquercetin-3-O-β-D-glucopyranoside (2), and 6-methoxyquercetin-3-O-β-D-glucopyranoside (3). The developed method presented good validation parameters, showing that the results obtained are consistent and can be used in ensuring the quantification of these constituents in the extracts. Compounds 2 and 3 showed strong antiradical activity when compared with the positive controls (quercetin and gallic acid).

Os efeitos dos compostos isolados de líquens brasileiros e seus derivados na produção de NO e H2O2 foram estudados utilizando macrófagos murinos na tentativa de desvendar suas possíveis propriedades imunomodulatórias. A citotoxicidade dos compostos foi estudada utilizando o ensaio de MTT. A estimulação dos macrófagos foi avaliada através da determinação de NO (metodologia de Griess) e H2O2 (peroxidase de raíz forte/vermelho de fenol) no sobrenadante de culturas de macrófagos peritoneais de camundongos Swiss. Este estudo demonstrou atividade estimulante de alguns compostos fenólicos e seus derivados na produção de NO e H2O2. A relação estrutura atividade sugere inúmeras direções sintéticas para futuros melhoramentos da atividade imunológica.

The effects of isolated compounds from Brazilian lichens and their derivatives on H2O2 and NO production were studied using murine macrophages as a part of an attempt to understand their possible immunomodulatory properties. The compound cytotoxicity was studied using MTT assay. Macrophage stimulation was evaluated by the determination of NO (Griess assay) and H2O2 (horseradish peroxidase/phenol red) in supernatants of peritoneal macrophage cultures of Swiss mice. This research demonstrated stimulatory activities of some phenolic compounds isolated from lichens and their derivatives on H2O2 and NO production. Structure-activity relationships suggest several synthetic directions for further improvement of immunological activity.

Espécies de Byrsonima, família Malpighiaceae, são popularmente conhecidas como "murici". Existem várias propriedades atribuídas às folhas de espécies de Byrsonima incluindo febrífuga, no tratamento de disfunções gastrintestinais e doenças de pele. Neste trabalho avaliamos a atividade antimicrobiana dos extratos das folhas de Byrsonima fagifolia, B. basiloba e B. intermedia usando o método de difusão em disco. Os resultados obtidos mostraram que os extratos metanólicos das folhas apresentaram atividade antimicrobiana contra todos os microrganismos testados.

Byrsonima species, family Malpighiaceae, is popularly known as "murici". There are several properties attributed to the leaves of Byrsonima species including febrifuge, to treat gastrointestinal dysfunctions and skin diseases. In this work, the antimicrobial activity of Byrsonima fagifolia, B. basiloba and B. intermedia extracts obtained from the leaves were evaluated by using the disc-diffusion method. The results obtained showed that the methanol extracts of leaves had presented antimicrobial activity against all the microorganisms tested.

Neea theifera Oerst. (Nyctaginaceae) é amplamente utilizada na medicina popular brasileira para tratamento de úlceras gástricas e inflamação. A investigação fitoquímica das folhas de Neea theifera permitiu o isolamento e identificação da nova flavona luteolina-7-O-[2''-O-(5'''-O-feruloil)- beta-D-apiofuranosil]-beta-D-glucopiranosídeo (1) além dos oito compostos conhecidos vitexina, isovitexina, isoorientina, orientina, vicenina-2, crisoeriol, apigenina e luteolina. A identificação química foi realizada por métodos espectroscópicos incluindo RMN-2D, bem como análises no UV e IES-EM.

Neea theifera Oerst. (Nyctaginaceae) is widely used in Brazilian folk medicine for the treatment of gastric ulcers and inflammation. Phytochemical investigation of the leaves of Neea theifera afforded the isolation of the new flavone luteolin-7-O-[2''-O-(5'''-O-feruloyl)- beta-D-apiofuranosyl]-b-D-glucopyranoside (1) besides the eight-known compounds vitexin, isovitexin, isoorientin, orientin, vicenin-2, chrysoeriol, apigenin and luteolin. Their chemical identification was established by NMR spectroscopic methods including 2D-NMR, as well as UV and ESI-MS analyses.

Folhas e cascas de algumas especies do gênero Byrsonima (Malpighiaceae) são empregadas popularmente contra diarréia. Contudo, não existem dados na literatura à respeito de investigacões químicas ou farmacológicas dos extratos de B. cinera. Neste estudo, nós avaliamos a atividade antidiarreica dos extratos metanólico e hidrometanólico das folhas de B. cinera em ratos Swiss. Os resultados mostraram que ambos os extratos reduziram signitivamente a motilidade intestinal. Investigacão fitoquímica do extrato metanólico levou ao isolamento e identificacão da (+)-catequina e da quercetina-3-O-a-L-arabinopiranosídeo. A atividade observada pode estar correlacaionada com a presença dessas substâncias nos extratos.

Leaves and bark of some Byrsonima species (Malpighiaceae) are popularly employed against diarrhoeal diseases. However, no data were reported in the literature about the chemisty and pharmacology of extracts from B. cinera leaves. In the present study we evaluated the anti-diarrhoeal activity of methanolic and hydromethanolic extracts obtained from the leaves of B. cinera in Swiss mice. Results showed that both extracts reduced significantly the gastrintestinal motility. Phytochemical evaluation of the methanolic extract led to the isolation and identification of (+)-catechin and quercetin-3-O-a-L-arabinopyranoside. The observed activity may be correlated to the presence of these compounds in the extract.