The use of eco-friendly corrosion inhibitors in metallurgical processing has increased interest due to the reduced environmental impact. Hence, the inhibitory effect of Aniba canelilla (Lauraceae) extract was studied in the corrosion of carbon steel in 1.0 mol∙L-1 hydrochloric acid solution. This acid is used during the surface treatment of steel processing. The carbon steel protection was observed by varying the extract concentration from 50 to 300 mg∙L-1. Polarization curves revealed that this extract acted as an adsorption inhibitor decreasing both anodic and cathodic current densities. A relatively high inhibition corrosion efficiency, close to 97%, was obtained with plant stem extracts by gravimetric measurements. Weight loss measurements showed that the extract remains active for at least 72 hours at room temperature. The adsorption process of this extract is properly represented by the Langmuir isotherm. Atomic force microscopy shows that inhibited acid medium produces a smooth surface.

The inhibitory effect of Bauhinia purpurea (Fabaceae) extract was studied in the corrosion of carbon steel in 1.0 mol∙L-1 sulfuric acid solution. This plant was collected from the Brazilian rainforest. The carbon steel protection was observed by varying the extract concentration from 50 to 500 mg∙L-1. Polarization curves revealed that this extract acted as an adsorption inhibitor decreasing both anodic and cathodic density currents. Weight loss measurements showed that the extract remains stable for at least 72 hours. The adsorption process of this extract obeyed the Langmuir adsorption isotherm. Lastly, Arrhenius plot suggested the physical adsorption of the extract.

Bauhinia purpurea (Fabaceae). Plants of the Bauhinia species (Fabaceae) are used in the treatment of several infections and diseases, especially diabetes. In this paper, with an aim to contribute to the knowledge of the chemistry and therapeutic potential of the Amazonian species of the genus Bauhinia, flavonoid profiles in the leaves and branches of Bauhinia purpurea collected in Manaus and São Gabriel da Cachoeira/AM were analyzed by HPLC-DAD and ESIMS. Differences in the flavonoid profiles were detected along with the presence of rutin and isoquercitrin in the leaves collected in Manaus. All samples showed antioxidant activity, however, no cytotoxic activity against cell lines MDA-MB435 (breast), HCT-8 (colon), and SF-295 (glioblastoma) could be detected.

Os óleos essenciais das folhas e galhos de Sextonia rubra foram obtidos por hidrodestilação e analisados por cromatografia em fase gasosa com detectores de ionização de chama e espectrometria de massas. O α-pineno (21,7%), β-pineno (15,4%), α-copaeno (12,5%) e o germacreno D (12,1%) foram identificados como constituintes majoritários no óleo essencial das folhas. No óleo essencial dos galhos foram identificados como constituintes majoritários o α-copaeno (22,9%), β-selineno (7,9%) e o β-elemeno (7,2%). A composição química destes óleos essenciais está sendo relatada pela primeira vez neste trabalho.

The essential oils of the leaves and branches of Sextonia rubra were obtained by hydrodistillation and analyzed by GC-FID and GC-MS. In the leaves were identified as the major constituents α-pinene (21.7%), β-pinene (15.4%), α-copaene (12.5%) and germacrene D (12.1%). In the branches essential oil, α-copaene (22.9%), β-selinene (7.9%) and β-elemene (7.2%) were identified as the most abundant constituents. This paper describes for the first time the composition of these essential oils.

O objetivo deste trabalho foi caracterizar o óleo-resina da copaíba (Copaifera reticulata) e estimar, por meio de marcadores microssatélites, a variabilidade genética da espécie na Floresta Nacional do Tapajós, PA. A amostragem foi realizada em duas áreas, distanciadas de 5 km, em 136 árvores. A diversidade genética foi avaliada com seis marcadores microssatélites derivados de C. langsdorffii, e o óleo obtido de 30 árvores (15 de cada área) foi caracterizado em termos físicos e químicos. O óleo C. reticulata apresenta aspecto líquido, fino, odor fraco e de coloração amarelo-dourada (73,3% das plantas), com viscosidade muito variável (18 a 187 Pa-s) e densidade média de 0,975±0,049 g cm-3. O índice de acidez variou de 9,62 a 10,17 mg g-1 de KOH e o de saponificação de 100,63 a 109,84 mg g-1. A análise molecular identificou 78 alelos, com média de 13 por loco. A heterozigosidade esperada variou 0,59 a 0,85 (média de 0,75), com nível de endogamia de 0,375 a 0,419. Houve pouca diferenciação genética entre as populações das diferentes áreas de coleta (F ST = 0,030), mas a variabilidade foi maior entre os grupos genéticos detectados pelo programa Structure (F ST = 0,070). Essa maior variabilidade indica que não há ameaças à conservação genética da copaíba, em médio prazo.

The objective of this work was to characterize the oleoresin of copaiba (Copaifera reticulata) and to estimate genetic variability of the species in the Tapajós National Forest, PA, Brazil, using microsatellite markers. Sampling was performed in two areas, 5 km apart, in 136 trees. Genetic diversity was evaluated with six microsatellite markers derived from C. langsdorffii, and the oleoresin obtained from 30 trees (15 from each area) was physically and chemically characterized. Oleoresin from C. reticulate has a liquid, thin aspect, with a weak odor and yellowish-gilded color (73.3% of the plants), highly variable viscosity (18 to 187 Pa-s), and mean density of 0,975±0,049 g cm-3. Its acidity index varied from 9.62 to 10.17 mg g-1 of KOH and the saponification index from 100.63 to 109.84 mg g-1. The molecular analysis identified 78 alleles, with an average of 13 per locus. The expected heterozygosity varied from 0.59 to 0.85 (mean of 0.75) and the inbreeding level, from 0.375 to 0.419. The genetic differentiation between populations in the different sampling areas was low (F ST = 0.030), but the variability was higher between the genetic groups detected by Structure software (F ST = 0.070). This higher variability indicates that the genetic diversity of copaiba is not threatened in the mid-term.

Lauraceae é uma das famílias mais importantes na floresta amazônica. Diversas de suas espécies apresentam em sua composição substâncias com pronunciadas atividades biológicas. Nesse trabalho, os extratos obtidos em etanol de galhos e folhas de 20 espécies de Lauraceae foram coletados na Reserva Florestal Ducke e avaliados quant o às atividades antioxidante frente ao radical livre 2,2-difenil-1-picrilhidrazila(DPPH) e inibidora da enzima acetilcolinesterase. O extrato dos galhos de Licaria martinianal apresentou a maior capacidade de sequestro do radical DPPH (6,96 µg.mL-1),mas os extratos de Ocotea iminor foram os mais ativos na inibição da enzima acetilcolinesterase, apresentando também pronunciada atividade antioxidante. O perfil de atividade antioxidante e anticolinesterásico destes extratos está sendo relatado pela primeira vez neste trabalho.

Lauraceae is one of the most important families in the Amazon rainforest. Several substances with strong pharmacological properties have been isolated from the species of this family. In this study, ethanol extracts of branches and leaves of 20 Lauracea especies were collected in the Reserva Florestal Ducke and evaluated for antioxidant activity of extracts using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and inhibition of acetylcholinesterase. The branches extracts from Licaria martinianal showed the highest capacity to scavenge the DPPH radical (6.96 µgmL-1), but Ocotea iminor extracts were the most active in inhibiting the enzyme acetylcholinesterase, with also pronounced antioxidant activity. The antioxidant and acetylcholinesterasic activities profile of these extracts is being reported in the first time in this paper.

Substances that inhibit the growth of Mycobacterium tuberculosis could potentially be used as antibiotics. These substances could also be added to test culture media to improve the speed of tuberculosis diagnosis. The aim of this work was to investigate the influence of culture filtrates of endophytic fungi isolated from P. aduncum L. on the growth of M. tuberculosis. To achieve this objective, the following methodology was used: a) endophytic fungi were isolated from the leaves and stems of P. aduncum L.; b) the isolated fungi were submitted to submerged bioprocessing; c) culture filtrates from the bioprocess were assayed to evaluate their effect on the growth of M. tuberculosis. We isolated 315 fungal types, which represented 85 morphologies, from different parts of P. aduncum L. The bioassays were performed on 82 culture filtrates and 6 plant extracts and resulted in the detection of 1 culture filtrate that stimulated the growth of M. tuberculosis and 15 that inhibited microbial growth. None of the phytochemical extracts had an effect on the growth of M. tuberculosis. In conclusion, we observed that the endophytic fungi isolated from P. aduncum L. (Piperaceae) produced extracellular metabolites (present in the culture filtrate) that affect the growth of M. tuberculosis. These compounds have the potential to be used as antimicrobials or in the diagnosis of tuberculosis.

Os óleos essenciais das folhas e caules de Rhodostemonodaphne parvifolia coletada na Reserva Florestal Adolpho Ducke foram obtidos por hidrodestilação e analisados por cromatografia em fase gasosa com detector de ionização de chama e espectrometria de massas. Treze constituintes foram identificados nas folhas, dos quais o ß-cariofileno foi o que apresentou maior percentual (41,30%). Nos caules foram identificados quinze compostos, com predominância dos sesquiterpenos ß-cariofileno (16,20%) e epi-cedrol (13,30%) e do monoterpeno linalol (15,40%). Os óleos foram analisados em ensaios químicos, de sequestro do radical livre DPPH, e enzimáticos, de inibição da enzima acetilcolinesterase. Nos ensaios de sequestro de radicais livres, apesar de terem se mostrado ativos em ensaios qualitativos, os óleos essenciais apresentaram fraca atividade antioxidante no ensaio quantitativo (inativos em concentração inferior a 1.000 µg/mL). A inibição da acetilcolinesterase só foi observada nos óleos essenciais das folhas. A composição química e a atividade biológica destes óleos estão sendo relatadas pela primeira vez neste trabalho.

The essential oils of leaves and stems of Rhodostemonodaphne parvifolia collected in the Adolpho Ducke Forest Reserve were obtained by hydrodistillation and analyzed by GC-FID and GC-MS. Thirteen components were identified in the leaf oil, of which ß-caryophyllene was the major (41.30%). Fifty components were identified in the stem oil, among them the sesquiterpenes ß-caryophyllene (16.20%) and epi-cedrol (13.30%), together with the monoterpene linalool (15.40%). The essential oils were analyzed at chemical, DPPH free radical scavenging; and enzymatic bioassays, acetylcholinesterase inhibition. At antioxidant DPPH assays, the oils showed to be active at the qualitative assay but only weakly active at quantitative test (inactive at concentration lower than 1,000 µg/mL). The inhibition of acetylcholinesterase was detected only in leaves essential oils. This paper describes for the first time the composition of these essential oils and their biological activities.

Um dos materiais utilizados para a adequação do meio bucal no serviço público é o cimento produzido a partir de óxido de zinco e eugenol. Entretanto, o eugenol é uma substância citotóxica que pode desencadear alguns efeitos adversos. Por essa razão, procura-se substituir o eugenol por uma substância que apresente baixa toxicidade, mantendo ou mesmo melhorando as propriedades do cimento. O óleo-resina de copaíba é um produto natural, utilizado pelas populações amazônicas e reconhecido por suas propriedades medicinais. Baseando-se nas propriedades desse óleo-resina, na ação antimicrobiana comprovada do hidróxido de cálcio e na ação anti-séptica do óxido de zinco, propôs-se formular um cimento odontológico obtido da associação do ZnO, Ca(OH)2 e óleo-resina de Copaifera multijuga Hayne e avaliar sua atividade antibacteriana através do teste de diluição em meio líquido frente às cepas padrão de Streptococcus mutans (ATCC 25175) e S. sanguinis (ATCC 15300). Nesse ensaio, utilizaram-se os seguintes grupos experimentais: o cimento contendo ZnO, Ca(OH)2 e óleo-resina de copaíba (G1) e cada um dos constituintes isoladamente, ZnO (G2), Ca(OH)2 (G3) e óleo-resina de copaíba (G4). Todos os grupos analisados demonstraram atividade antibacteriana, o G4 apresentou os melhores resultados e o G1 mostrou-se um cimento promissor a ser utilizado em odontologia.

One of the materials utilized for suitability of the oral means in the public service is the cement produced from zinc oxide and eugenol. However, eugenol is a cytotoxic substance that can trigger some adverse effects. For this reason, it is desired to replace eugenol for another substance that presents low toxicity, keeping or even improving the cement properties. The copaiba oil-resin is a natural product, utilized by the Amazonian population and recognized for its medicinal properties. Based on the properties of this oil-resin, on the proven antimicrobial activity of calcium hydroxide and on the anti-septic action of zinc oxide, it was proposed to formulate a dental cement obtained through the association of ZnO, Ca(OH)2 and Copaifera multijuga Hayne oil-resin and assess its antibacterial activity through the test of dilution in aqueous medium against the standard of Streptococcus mutans (ATCC 25175) and S. sanguinis (ATCC 15300). In this assay, the following experimental groups were utilized: the cement containing ZnO, Ca(OH)2 and copaiba oil-resin (G1) and each one of the constituents individually, ZnO (G2), Ca(OH)2 (G3) and copaiba oil-resin (G4). All the analyzed groups showed antibacterial activity, G4 showed the best results and G1 showed itself to be a promising cement for application in dentristy.

The selective ion monitoring acquisition mode in mass spectrometry was applied to identify, in the diesel complex matrix, the raw materials (vegetable oil and alcohol) that originate biodiesel. Biodiesel samples obtained from babassu, castor, palm and soybean vegetable oils and pure fatty acid methyl and ethyl esters were used to develop this method, using specific fragments in mass spectrometry and the "window system" in gas chromatography. The commercial Brazilian B2 samples were found to be produced with soybean oil, transesterified with methanol.

Plant extracts are usually complex mixtures which contain several molecules of different sizes with varied functional groups. Such extracts are a challenge to the chemist of natural products. Ion exchange chromatography in non-aqueous medium, used for separation of basic or acidic fractions from plant extracts, is an important unit operation in preparative scale separations. Anionic macroporous resin in non-aqueous medium was used with success in this study for separation of the acid fraction of Copaifera multijuga (Copaiba oil), rich in labdanic diterpenes and for the methanolic extract of Croton cajucara (acetyl aleuritoric acid).