178 research outputs found
Plantas Oleaginosas Amazônicas: Química e Atividade Antioxidante de Patauá (Oenocarpus bataua Mart.)
The Amazon oilseeds, especially from native palm trees are significant species belonging to the Amazon landscape and culture. The Amazon species produce oil with great potential to generate valuable medicines, cosmetics, nutraceuticals and energy. The Oenocarpus bataua (patawa) is an edible species and from its fruits is produced the "vinho de patauá", a well-known beverage, considered very nutritive and energetic. Fresh fruits collected nearby Manaus-AM, were separated into peel, pulp and seeds. The methanolic extracts from pulp and seeds were evaluated in different antioxidant assays and both extracts were considered active. The seed extract showed antioxidant activity compared to the positive control (quercetin) in the radical scavenging-DPPH assay. The pulp extract were fractionated guided by TLC-antioxidant analysis that led to the isolation of the stilbene, piceatannol. This is the first report of an isolated compound from patawa. Piceatannol is considered a bioactive compound and in some cases was considered more active than resveratrol, a well-known bioactive compound. These results showed the great potential of patawa to produce nutraceutical products
Alcaloides indólicos de cascas de Aspidosperma vargasii E A. desmanthum
Fractionation of extracts resulted in isolation and identification of indole alkaloids ellipticine and N-methylteti:ahydroellipticine from. A. vargasii and aspidocarpine from A. desmanthum. Identification of these compounds was achieved based on IR, MS, 1H, 13C and 2-D NMR data and comparison to data in the literature
Characterization of bergenin in endopleura uchi bark and its anti-inflammatory activity
Endopleura uchi (Huber) Cuatrec. is an Amazon species traditionally used for the treatment of inflammations and female disorders. Pure bergenin was isolated from the methanolic extract of bark of E. uchi, firstly by using liquid-liquid partition chromatography followed by column chromatography over Sephadex LH-20 and then silica gel 60 flash chromatography. The structure of bergenin was identified on the basis of its NMR spectra. The in vitro anti-inflammatory activity was determined by the measurement of the inhibitory concentration (IC) of bergenin against three key enzymes: COX-1, COX-2 (cyclooxygenases) and phospholipase A2 (PLA2). These enzymes were selected because they are important targets for the discovery of new anti-inflammatory drugs associated with the biosynthesis of prostaglandins. The IC50 of bergenin for phopholipase A2 was determined as 156.6 μmol L-1 and bergenin was not considered active as compared to the positive control, tioetheramide PC. Bergenin did not inhibit COX-1 as well (IC50 = 107.2 μmol L-1). However, bergenin selectively inhibited COX-2 (IC50 = 1.2 μmol L-1). Because of the use of E. uchi in traditional medicine, bergenin was quantified in teas prepared as prescribed in traditional medicine by RP-HPLC as being 3% in the bark of E. uchi. The inhibitory activity towards COX-2 is important, since selective inhibitors of COX-2 have been clinically validated as anti-inflammatory therapeutics due to their enhanced gastrointestinal safety. ©2009 Sociedade Brasileira de Química
Constituintes químicos dos galhos de simaba guianensis subesp. ecaudata (cronquist)
Simaba guianensis subesp. ecaudata (Simaroubaceae) is a tree found in the Brazilian Amazon. This work describes for the first time the fractionation of stems of this species that resulted in the isolation of the cytotoxic triterpene piscidinol A, the alkaloid 9-methoxycanthin-6-one, caryophyllene oxide, also isolated for the first time from this species and a new alkaloid (6-methoxy-(9H-β-carbolin-1-il)-(Z)-2-propenoic acid). Quantification of 9-methoxycanthin-6-one in different extracts and fractions of stems of S. guianensis by high performance liquid chromatography was also performed. The concentration of 9-methoxycanthin-6-one in methanolic and aqueous extracts were inferior to the known cytotoxic concentration of this compound
Triterpenos e alcalóide tipo cantinona dos galhos de Simaba polyphylla (cavalcante) W.W. Thomas (simaroubaceae)
Simaba polyphylla is a small tree found in the Amazon region, known by the common names "marupazinho" or "serve para tudo". It is used in traditional medicine for the treatment of fevers. This work describes the phytochemical study of the hexane extract and chloroform fraction obtained by partitioning the methanol extract of stems, which led to isolation and identification of the triterpenes niloticin, dyhidroniloticin, taraxerone and of the cytotoxic alkaloid 9-methoxy-canthin-6-one. These compounds are described for the first time in S. polyphylla
The use of tucumã of amazonas kernel oil in the biodiesel production
The shortage of electricity is a major reason for the low Human Development Index of isolated communities located in the Amazon basin. The biodiesel produced from vegetable oils extracted from oil seeds native species, in a sustainable way, is one of the best alternative energy for the region. The \x93tucumã of amazonas\x94, Astrocaryum aculeatum, is an Amazon palm tree that produces a much appreciated fruit in the region, from which it obtains kernels that have high content in oil. In this study, we evaluated the production of ethyl biodiesel, from different batches of oil obtained from \x93tucumã of amazonas\x94 kernels with high and low acidity by the transesterification process acidic and basic catalysis, respectively. Different acid catalysts (HCl and H2SO4) and concentrations of each acid (from 0.0625 to 1.000 M) were tested, with ethanol at molar ratio of 1:6 at 90º C for 24 h. In the basic catalysis, NaOH and KOH were tested at the concentration range of 0.5 to 2.0 % with anhydrous ethanol with molar ratio 1:12 and the reactions took place at 80º C for 2 h. The conversion into biodiesel and its quality was analyzed by means reversed-phase high performance liquid chromatography (RP-HPLC) and specific gravity. Chromatographic analysis indicated that the best conversions were achieved by samples of biodiesel with lowest specific gravity (0.87 g.cm-1). The samples of biodiesel with best quality were obtained with acid catalysis at 1.0 M with yield above 90 %. In the basic catalysis, it could be obtained biodiesel with good quality with NaOH at 2.0 %, but at lower yields. However in both types of catalysis, it was possible to identify an excellent potential for the production of this important biofuel from tucumã kernel oil.A falta de disponibilidade de energia elétrica é um dos principais motivos pelo baixo Índice de Desenvolvimento Humano das comunidades isoladas localizadas na Amazônia. O biodiesel produzido a partir de óleos vegetais extraídos de espécies oleaginosas nativas de forma sustentada é uma das melhores alternativas energéticas para a região. O tucumã do amazonas, Astrocaryum aculeatum, é uma espécie de palmeira que produz um fruto muito apreciado na região, a partir do qual se obtém uma amêndoa com alto teor de óleo. Nesse estudo, foi avaliada a produção de biodiesel etílico, a partir de diferentes lotes de óleos de tucumã do amazonas, com índices de acidez baixos e elevados, pela transesterificação por catálise básica e ácida homogêneas, respectivamente. Na catálise ácida, foram testados HCl e H2SO4 como catalisadores nas concentrações de 0,0625 a 1,000 M, empregando etanol hidratado na proporção molar de 1:6 e a reação conduzida a 90 ºC por 24 h. Na catálise básica, foram testados NaOH e KOH, nas proporções de 0,5 a 2,0 %, empregando etanol anidro na proporção molar de 1:12 e a reação conduzida a 80 ºC por 2 h. O biodiesel obtido em cada experimento foi analisado por métodos físicos (massa específica) e cromatográficos (CLAE em fase reversa). Análises cromatográficas indicaram que as melhores conversões foram alcançadas por amostras de biodiesel com massas específicas inferiores a 0,87 g.cm-1. As amostras de biodiesel obtidas com melhor qualidade foram obtidas utilizando-se os catalisadores ácidos a 1,0 M com rendimentos superiores a 90%. No caso da catálise básica, obteve-se biodiesel de boa qualidade empregando-se o catalisador NaOH a 2,0%, porém com rendimento inferior a 60 %. Contudo, em ambos os casos, foi possível identificar um excelente potencial de produção de biocombustível, a partir do óleo das amêndoas de tucumã
Aromatic compounds from three brazilian lauraceae species
Phytochemical investigations on three Brazilian Lauraceae species from, the Cerrado region of São Paulo State, Ocotea corymbosa (Meins) Mez., O. elegans Mez. and Persea pyrifolia Nees & Mart. ex Nees resulted in the isolation of flavonoids, an ester of the 4-O-E-caffeoylquinic acid, an aromatic sesquiterpene besides furofuran lignans. This is the first chemical study on the leaves of Ocotea elegans and O. corymbosa as well as the first report of non-volatile compounds from Persea pyrifolia
Leaf and stem anatomy of Picrolemma sprucei Hook (Simaroubaceae)
Anatomical studies of the leaves and stems of Picrolemma sprucei revealed that the epidermes of the leaves are glabrous, with undulating cell walls and anomocytic stomata. The mesophyll is dorsiventral with a layer of cells in palisade and a spongy parenchyma. The vascular bundles are bicollateral and have a dark tannin containing idioblast. The stem possesses a developed cortical parenchyma with schlerenchymatous thick walled cells. These are either isolated or gathered in small groups. Internally the vascular region exhibits xylematic vessels some isolated and some in groups submerged in fibrous tissue. The stem possesses a paratracheal, vasicentric parenchyma with central pith. Histochemical tests (sudan III and ferric chloride) made on the central section of the midrib and on the petiole showed the presence, respectively, of tannin or oleoresin in some cells.Os estudos anatômicos das folhas e caules de Picrolemma sprucei revelaram que as epidermes das folhas são glabras, apresentam células de paredes onduladas e estômatos anomocíticos. O mesofilo é dorsiventral com uma camada de células em paliçada e um parênquima lacunoso. Os feixes vasculares são bicolaterais e apresentam idioblastos escuros de conteúdo tânico. No caule evidencia-se um parênquima cortical desenvolvido, com células de natureza esclerenquimática, isoladas ou reunidas em pequenos grupos, de paredes espessas. Internamente observa-se a região vascular com vasos xilemáticos isolados ou em grupos imersos em tecido fibroso, sendo o parênquima do tipo paratraqueal, vasicêntrico. Na região central encontra-se uma medula desenvolvida. Testes histoquímicos (sudam III e cloreto férrico) realizados na nervura mediana do terço médio do limbo foliar e no pecíolo revelaram respectivamente, a presença de um conteúdo tânico e óleo-resinoso em algumas de suas células
Chemical constituents isolated from twigs and barks of amapazeiro (Parahancornia amapa, Apocynaceae)
Parahancornia amapa (Apocynaceae) is typical of the Amazon region and popularly known as amapazeiro and widely used in folk medicine in the Amazon region. The objective of this work was to study the phytochemical composition of twigs and barks of this species. From the dichloromethane extract of twigs were isolated β-sitosterol, stigmasterol, and pentacyclic triterpenoids α-amyrin, β-amyrin, lupeol and friedelin. From the methanol extract of barks was isolated indole alkaloid isositsiriquina. The structures of these compounds were identified by analysis of the mass spectra high-resolution, ¹H and 13C NMR and comparisons with literature data. This is the first report of isolation of alkaloid in this genus.Parahancornia amapa (Apocynaceae) é típica da região amazônica e conhecida popularmente como amapazeiro e muito utilizada na medicina popular da região Amazônica. O objetivo desse trabalho foi o estudo fitoquímico dos galhos e cascas dessa espécie. Do extrato diclorometânico dos galhos foram isolados o β-sitosterol, estigmasterol, além de triterpenóides pentacíclicos, α-amirina, β-amirina, lupeol e friedelina. Do extrato metanólico das cascas foi isolado o alcaloide indólico isositsiriquina. As estruturas desses compostos foram identificadas por análise dos espectros de massa de alta resolução, Ressonância Magnética Nuclear de ¹H e 13C e comparações com dados da literatura. Esse é o primeiro relato de isolamento de alcaloide neste gênero
- …