RESUMO Basidiomicetos de podridão branca são capazes de deteriorar madeira e atuar como patógenos de árvores. A flora tropical é uma importante fonte de compostos antifúngicos ecologicamente seguros, entretanto, o conhecimento de como extratos vegetais afetam a fisiologia fúngica é limitado. Portanto, neste trabalho foi investigada a influência de extratos etanólicos de folhas de Casearia sylvestris e C. decandra, na concentração de 0,1 mg mL-1, sobre a produção de enzimas ligninolíticas por Trametes villosa, Ganoderma australe e Pycnoporus sanguineus. De modo geral, os extratos inibiram o crescimento micelial e a produção de biomassa. Além disso, o extrato de C. sylvestris reduziu a produção de manganês peroxidase e lacase, porém as respostas ao extrato de C. decandra foram variáveis. Deste modo, enzimas envolvidas na degradação da lignina são alvos potenciais para o controle de fungos causadores de podridão em madeira por compostos vegetais bioativos, uma vez que a capacidade desses microrganismos para colonizar o substrato pode ser prejudicada.

ABSTRACT White-rot basidiomycetes are able to deteriorate wood products and be pathogenic to living trees, requiring, thus requiring control. The tropical flora is an important source of eco-friendly antifungal compounds; however, the knowledge on how leaf extracts affect the fungal physiology is limited. Therefore, in the present work we investigated the influence of ethanolic leaf extracts of Casearia sylvestris and C. decandra at 0.1 mg mL-1 on the production of ligninolytic enzymes by Trametes villosa, Ganoderma australe and Pycnoporus sanguineus. Overall, the extracts inhibited the mycelial growth and the production of biomass. Additionally, C. sylvestris extract reduced the production of manganese peroxidase and laccase; however, the exposure to C. decandra extract resulted in variable responses. Therefore, enzymes related to lignin degradation are potential targets to control wood decay fungi by plant bioactive compounds, as their ability to colonize the substrate may be impaired.

RESUMO Geoprópolis, uma mistura de resinas vegetais, cera, terra e secreção salivar, produzida pela abelha sem ferrão Melipona fasciculata. Este estudo investigou a composição química e a atividade antioxidante da geoprópolis coletada em colmeias em duas regiões fitogeográficas de campos alagados e de cerrado, nos municípios de Palmeirândia e Fernando Falcão, no Estado do Maranhão, Nordeste do Brasil. Os compostos da geoprópolis foram identificados por cromatografia gasosa acoplada a espectrometria de massas (CG/EM). Foram determinados os teores de fenólicos totais pelo reagente de Folin−Ciocalteu, e atividade antioxidante utilizando o ensaio in vitro com 2,2-difenil-1-picrilhidrazil (DPPH) e capacidade redutora do ferro (FRAP). As quatro amostras de geoprópolis apresentaram variações no teor de fenólicos totais e atividade antioxidante, as geoprópolis de Fernando Falcão, apresentaram maiores teores. Nas geoprópolis do município de Palmeirândia foram identificados, triterpenos do tipo cicloartano, ursano e oleanano e ácidos fenólicos (ácido protocatecuico e ácido gálico), enquanto que na geoprópolis de Fernando Falcão, ácidos fenólicos, ácido gálico e elágico foram os principais constituintes. A propriedade antioxidante da geoprópolis pode ser atribuída aos altos teores de fenólicos totais e de ácido gálico e elágico. Os resultados demonstram que as fontes vegetais das duas regiões fitogeográficas do Maranhão, Brasil, utilizadas pelas abelhas para a produção da geoprópolis contribuem para a composição química e bioatividade deste produto.

ABSTRACT Geopropolis, a mixture of plant resin, wax, soil and salivary secretion, is produced by the stingless bee Melipona fasciculata. This aim of this study was to investigate the chemical composition and antioxidant activity of geopropolis collected from beehives in two phytogeographical regions, flooded fields and cerrado, in the municipalities of Palmeirândia and Fernando Falcão, Maranhão State, northeastern Brazil. The geopropolis compounds were identified by gas chromatography-mass spectrometry (GC/MS). Additionally, total phenolic content was determined with the Folin−Ciocalteu reagent and antioxidant activity was evaluated in vitro by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. The four geopropolis samples varied in terms of total phenolic content and antioxidant activity and the highest values were observed for geopropolis from Fernando Falcão. Triterpenes such as cycloartane, ursane and oleanane and phenolic acids (protocatechuic acid and gallic acid) were identified in the geopropolis from Palmeirândia, while the phenolic acids, gallic and ellagic acid were the main compounds in geopropolis from Fernando Falcão. The antioxidant property of geopropolis is due to its high total phenolic content and predominance of gallic acid and ellagic acid. The results showed that the plant resources in two phytogeographical regions of Maranhão used by bees for the production of geopropolis contribute to the chemical composition and bioactivity of this product.

Pera glabrata (Schott) Baill. foi selecionada para este estudo a partir de uma triagem de espécies vegetais da Mata Atlântica na busca de substâncias com atividades anticolinesterásica e antifúngica. A técnica da bioautografia direta foi utilizada para a detecção das atividades anticolinesterásica e antifúngica. O extrato etanólico bruto obtido das folhas foi particionado com hexano, clorofórmio e acetato de etila. A fração clorofórmica ativa foi fracionada por cromatografia em coluna de sílica gel fornecendo 12 grupos. Do grupo nove foi isolado o alcalóide cafeína com limites de detecção de 0,1 e 1,0 µg para as atividades anticolinesterásica e antifúngica, respectivamente. Após bioensaio em microplaca, somente os grupos quatro, nove, 10, 11 e 12 apresentaram inibição da acetilcolinesterase maior ou igual a 40%. O grupo 12 foi purificado por cromatografia em camada delgada preparativa de sílica gel fornecendo quatro sub-frações. Duas sub-frações deste grupo foram analisadas por cromatografia a gás-espectrometria de massas e cromatografia a gás com detector de ionização de chama. A primeira sub-fração contém dois compostos majoritários: 9-hidroxi-4-megastigmen-3-ona (78%) e cafeína (6%), e apresentou atividade anticolinesterásica. A segunda sub-fração contém cinco compostos principais identificados como 9-hidroxi-4-megastigmen-3-ona, isololiolida, (-) loliolida, ácido palmítico e lupeol e não apresentou atividade.

Pera glabrata (Schott) Baill. was selected for this study after showing a preliminary positive result in a screening of Atlantic Forest plant species in the search for acetylcholinesterase inhibitors and antifungal compounds. The bioassays were conducted with crude ethanol extract of the leaves using direct bioautography method for acetylcholinesterase and antifungal activities. This extract was partitioned with hexane, chloroform and ethyl acetate solvents. The active chloroform fraction was submitted to silica gel chromatography column affording 12 groups. Caffeine, an alkaloid, which showed detection limits of 0.1 and 1.0 µg for anticholinesterasic and antifungal activities, respectively, was isolated from group nine. After microplate analyses, only groups four, nine, 10, 11 and 12 showed acetylcholinesterase inhibitory activity of 40% or higher. The group 12 was purified by preparative layer chromatography affording four sub-fractions. Two sub-fractions from this group were analyzed by gas chromatography-mass spectrometry and gas chromatography-flame ionization detector. The first sub-fraction showed anticholinesterasic activity and contained two major compounds: 9-hydroxy-4-megastigmen-3-one (84%) and caffeine (6%). The second sub-fraction presented five major compounds identified as 9-hydroxy-4-megastigmen-3-one, isololiolide, (-) loliolide, palmitic acid and lupeol and did not show activity.

Extratos brutos de 17 espécies de plantas coletadas em região de Mata Atlântica no Estado de São Paulo (Brasil) foram avaliadas para as atividades: antifúngica, no reparo do DNA e inibição da acetilcolinesterase. Dos 34 extratos obtidos de folhas e galhos das plantas analisadas para a atividade antifúngica com Cladosporium sphaerospermum e C. cladosporioides, 26,5% foram ativos. Todavia, apenas o extrato das folhas de Cabralea canjerana inibiu fortemente o crescimento dos dois fungos. No ensaio de reparo do DNA com linhagens mutantes de Saccharomyces cerevisiae, 11,7% dos extratos foram ativos, sendo que, 100% destes foram seletivos para o mecanismo de reparo do DNA envolvendo topoisomerase II. Das 17 espécies analisadas, 12 demonstraram atividade anticolinesterásica no ensaio qualitativo sobre cromatografia de camada delgada (CCD). No entanto, apenas os extratos de Tetrastylidium grandifolium (galhos) e Sloanea guianensis (folhas e galhos) apresentaram atividade anticolinesterásica maior que 50% no ensaio quantitativo.

Crude extracts from 17 plant species collected from an Atlantic Forest region in the State of São Paulo (Brazil) have been screened for antifungal, DNA-damaging and acetylcholinesterase inhibiting activities. Of the 34 extracts obtained from leaves and stems of plants assayed for antifungal activity with Cladosporium sphaerospermum and C. cladosporioides 26.5% were active. However, only the extract of leaves of Cabralea canjerana showed a strong inhibition of both fungi. The DNA-damaging assay with mutant strains of Saccharomyces cerevisiae resulted in 11.7 % of the extracts being active whereas 100% of them showed selectivity for the DNA-repair mechanism of topoisomerase II. Of the 17 species analysed, 12 showed anticholinesterasic activity in TLC assay. However, only extracts from Tetrastylidium grandifolium (stems) and Sloanea guianensis (leaves and stems) inhibited acetylcholinesterase activity more than 50% in quantitative assay.

The phytochemical investigation of the flowers of Pterogyne nitens (Caesalpinioideae) resulted in the isolation and identification of nine phenolic derivatives, quercetin 3-O-sophoroside, taxifolin, astilbin, ourateacatechin, caffeic, ferulic, sinapic, chlorogenic and gallic acid, besides two guanidine alkaloids, pterogynine, pterogynidine. This is the first time these compounds have been reported in P. nitens flowers. As this is a monospecific genus, these secondary metabolites may have taxonomical significance. Their structures were assigned on the basis of spectroscopic analyses, including two-dimensional NMR techniques.

Chromatographic fractionation of the EtOH extract from the leaves of Swartzia langsdorffii afforded the pentacyclic triterpenes oleanolic acid and lupeol, and two saponins: oleanolic acid 3-sophoroside and the new ester 3-O-b-D-(6'-methyl)-glucopyranosyl-28-O-b-D-glucopyranosyl-oleanate. Their structures were elucidated from spectral data, including 2D NMR and HRESIMS experiments. Antifungal activity of all isolated compounds was evaluated, using phytopathogens Cladosporium cladosporioides and C. sphaerospermum, and human pathogens Candida albicans, C. krusei, C. parapsilosis and Cryptococcus neoformans.

The aqueous extract (AE) and isolated fraction (ppt-3) of Cuphea carthagenensis (Jacq.) J. F. Macbr (sete-sangrias) were tested using models of nociception and inflammation in mice. Oral administration (p.o.) of the AE (10 to 100 mg/kg) and fraction ppt-3 (0.1 to 10 mg/kg) reduced the acetic acid-induced writhing in mice by 40 to 50% and by 46 to 70% of control, respectively. At the same doses AE and ppt-3 did not affect the tail flick response. Fraction ppt-3 also reduced the carrageenininduced paw edema, but at a dose 1000 times higher than that inducing antinociception. The results indicated the presence in the plant of antinociceptive constituents devoid of antiinflammatory activity, with actions apparently mediated by non-opioid mechanisms.

The hydroalcoholic extract of the powdered bark of the Indian-snuff Maquira sclerophylla Ducke was purified by column chromatography in silica-gel and the major cardenolide isolated from preparative TLC was identified by 1H-NMR, 1 2 C-NMR and IR analyses. The spectra showed that the active substance has strophanthidin as aglicone.