Controlling Asian soybean rust (Phakopsora pachyrhizi) with Bacillus spp. and coffee oil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Application of nanotechnology for the encapsulation of botanical insecticides for sustainable agriculture: Prospects and promises

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Lipid formation and γ-linolenic acid production by Mucor circinelloides and Rhizopus sp., grown on vegetable oil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Chemical and rheological properties of exopolysaccharides produced by four isolates of rhizobia

The rheological, physicochemical properties, emulsification and stability of exopolysaccharides (EPSs) from four rhizobia isolates (LBMP-C01, LBMP-C02, LBMP-C03 and LBMP-C04) were studied. The EPS yields of isolates under these experimental conditions were in the range of 1.5-6.63gL(-1). The LBMP-C04 isolate, which presented the highest EPS production (6.63gL(-1)), was isolated from Arachis pintoi and was identified as a Rhizobium sp. strain that could be explored as a possible potential source for the production of extracellular heteropolysaccharides. All polymers showed a pseudoplastic non-Newtonian fluid behavior or shear thinning property in aqueous solutions. Among the four EPS tested against hydrocarbons, EPS LBMP-C01 was found to be more effective against hexane, olive and soybean oils (89.94%, 82.75% and 81.15%, respectively). Importantly, we found that changes in pH (2-11) and salinity (0-30%) influenced the emulsification of diesel oil by the EPSs. EPSLBMP-C04 presented optimal emulsification capacity at pH 10 (E24=53%) and 30% salinity (E24=27%). These findings contribute to the understanding of the influence of the chemical composition, physical properties and biotechnology applications of rhizobial EPS solutions their bioemulsifying properties.

Efficacy of essential oil of Piper aduncum against nymphs and adults of Diaphorina citri

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluation of the anti-mycobacterium tuberculosis activity and in vivo acute toxicity of annona sylvatic

Background The recent emergence of extensively multidrug-resistant Mycobacterium tuberculosis strains has further complicated the control of tuberculosis. There is an urgent need for the development of new molecular candidates antitubercular drugs. Medicinal plants have been an excellent source of leads for the development of drugs. The aim of this study was to evaluate the in vitro activity of 28 alcoholic extracts and essential oils of native and exotic Brazilian plants against Mycobacterium tuberculosis and to further study these extracts through chemical fractionation, the isolation of their constituents, and an evaluation of the in vivo acute toxicity of the active extracts. To the best of our knowledge this is the first chemical characterization, antituberculosis activity and acute toxicity evaluation of Annona sylvatica. Methods The anti-mycobacterial activity of these extracts and their constituent compounds was evaluated using the resazurin reduction microtiter assay (REMA). To investigate the acute toxicity of these extracts in vivo, female Swiss mice were treated with the extracts at doses of 500, 1000 and 2000 mg · kg-1 of body weight. The extracts were characterized by LC-MS, and the constituents were isolated and identified by chromatographic analysis of spectroscopic data. Results Of the 28 extracts, the methanol extract obtained from the leaves of Annona sylvatica showed anti-mycobacterial activity with an minimal inhibitory concentration (MIC) of 184.33 μg/mL, and the ethyl acetate fraction (EAF) resulting from liquid-liquid partitioning of the A. sylvatica extract showed an MIC of 115.2 μg/mL. The characterization of this extract by LC-MS identified flavonoids and acetogenins as its main constituents. The phytochemical study of the A. sylvatica EAF resulted in the isolation of quercetin, luteolin, and almunequin. Conclusions Among the compounds isolated from the EAF, luteolin and almunequin were the most promising, with MICs of 236.8 μg/mL (827.28 μM) and 209.9 μg/mL (328.48 μM), respectively. The acute administration of the EAF fraction in doses of 500, 1000, and 2000 mg · kg-1 of body weight did not cause signs of toxicity in the treated animals.

Association of fat intake and socioeconomic status on anthropometric measurements of adults

We aimed to identify the influence of dietary fat profile on body mass index (BMI) and waist circumference (WC) in a middleclass general population sample. A cross-sectional study of 448 adults aged 35-85 years was carried out from January 2004 to December 2007. Patients were divided in two groups according to family income: Group 1 (G1) with higher income, and Group 2 (G2) with lower income. Demographic and socioeconomic status were identified, along with anthropometric data, health eating index (HEI) and dietary profile. The groups were similar with respect to gender, age, BMI and WC. HEI was higher in G1 due to a higher intake of protein (+12.8%), dairy products (p<0.001), higher intake of vegetables (p<0.01), fruit (p<0.001), and less dietary fat (-9.8%). The main contribution of fats was saturated fat for G1 (+5.0%) and polyunsaturated fat for G2 (+14.4%). Besides differences in socioeconomic status the groups had similar BMI and abdominal fatness. Only differences in fat profile were correlated with the anthropometric measures mostly explained by the lower vegetable oil intake in higher income participants.

Polyphenols in fruits and vegetables and its effect on human health

Polyphenols represent a group of chemical substances common in plants, structurally characterized by the presence of one or more phenol units. Polyphenols are the most abundant antioxidants in human diets and the largest and best studied class of polyphenols is flavonoids, which include several thousand compounds. Numerous studies confirm that they exert a protective action on human health and are key components of a healthy and balanced diet. Epidemiological studies correlate flavonoid intake with a reduced incidence of chronic diseases, such as cardiovascular disease, diabetes and cancer. The involvement of reactive oxygen species (ROS) in the etiology of these degenerative conditions has suggested that phytochemicals showing antioxidant activity may contribute to the prevention of these pathologies. The present review deals with phenolic compounds in plants and reports on recent studies. Moreover, the present work includes information on the relationships between the consumption of these compounds, via feeding, and risk of disease occurrence, i.e. the effect on human health. Results obtained on herbs, essential oils, from plants grown in tropical, subtropical and temperate regions, were also reported.

Polycyclic aromatic hydrocarbons and petroleum biomarkers in Sao Sebastiao Channel, Brazil: Assessment of petroleum contamination

Polycyclic aromatic hydrocarbons (PAHs) and non-aromatic hydrocarbons (NAHs), including n-alkanes, isoprenoids and petroleum biomarkers (terpanes, hopanes, steranes and diasteranes), were quantified by gas chromatography with flame ionization and mass spectrometer detectors in sediment samples collected from the Sao Sebastiao Channel (SSC), Brazil, where the largest Brazilian maritime petroleum terminal is located The concentrations of total PAHs. total n-alkanes and petroleum biomarkers ranged from below the detection limits to 370 ng g(-1,) 28 mu g g(-1), 2200 ng g(-1) (dry weight), respectively. The analysis of PAN distribution suggested combustion sources of PAHs as the main input for these compounds with smaller amount from petroleum contamination The distribution of petroleum biomarkers undoubtedly demonstrated petroleum as a source of anthropogenic contamination throughout the region. The assessment of petrogenic sources of contamination in marine sediment is more challenging if only PAH analysis were carried out, which demonstrates that more stable hydrocarbons such as petroleum biomarkers are useful for investigating potential presence of petroleum (C) 2009 Elsevier Ltd. All rights reserved.

Physico-chemical properties of Brazilian cocoa butter and industrial blends. Part II - Microstructure, polymorphic behavior and crystallization characteristics

The microstructural behavior of industrial standardized cocoa butter samples and cocoa butter samples from three different Brazilian states is compared. The cocoa butters were characterized by their microstructural patterns, crystallization kinetics and polymorphic habits. The evaluation of these parameters aided in establishing relationships between the chemical compositions and crystallization behavior of the samples, as well as differentiating them in terms of technological and industrial potential for use in tropical regions.

Chemical evaluation and thermal behavior of Brazil nut oil obtained by different extraction processes

Brazil nut richness has been widely studied aiming at finding transformation models that increase its yield, keep its quality, reduce costs, and increase its productivity. The objective of this study is to evaluate the spectroscopic profile and the chemical and thermal behavior of Brazil nut oil obtained by different extraction processes. Lipid soxhlet extractions with petroleum ether and hexane, and using hydraulic pressing and supercritical carbon dioxide (CO2) were performed. The physicochemical analyses showed an acidity index with significant differences between the samples obtained by hydraulic pressing and supercritical CO2. The peroxide index presented significant difference for the oil obtained by hydraulic pressing compared to that obtained by the other extraction processes. The fatty acid profiles showed a relevant presence of the omega series (w-3, w-6, and w-9) with significant differences for the extraction processes evaluated. The results of the thermogravimetric and differential analyses did not indicate changes in mass loss and presented predominantly exothermic behavior. The spectroscopic profiles indicate that the extraction processes do not change the spectral profile of the oils. (c) 2011 Elsevier Ltd. All rights reserved.

Influence of light, temperature and metallic ions on biodiesel degradation and corrosiveness to copper and brass

Corrosion is a relevant issue regarding the problem of biodiesel compatibility with polymers and metals. This work aims to evaluate the influence of the natural light incidence and temperature in the corrosion rate of brass and copper immersed in commercial biodiesel as well as biodiesel degradation after the contact with metallic ions. The characterization of corrosion behavior was performed by weight loss measurements according to ASTM G1 and ASTM G31. The experiments according to ASTM G1 were performed at room temperature in light presence and absence. Experiments were also conducted at 55 degrees C in order to compare with ASTM G31 that is also performed at that temperature. The biodiesel degradation was characterized by water content, oxidation stability, viscosity as well as XRF, IR and Raman spectroscopies. The results of ASTM G1 tests showed that the thickness loss for both metals determined at room temperature is slightly higher when there is light incidence and these values significantly decrease for the highest temperature. The results of ASTM G31 tests indicated that air bubbling along with higher temperature affects mostly immersed samples. Biodiesel in contact with metals shows significant degradation in its properties as evidenced by increasing water content, higher viscosity and lower oxidation stability. (C) 2012 Elsevier Ltd. All rights reserved.

H-1 low- and high-field NMR study of the effects of plasma treatment on the oil and water fractions in crude heavy oil

The chemical and physical properties of a Brazilian heavy oil submitted to plasma treatment were investigated by H-1 low-and high-field nuclear magnetic resonance (NMR) combined to the characterization of rheological properties, thermogravimetry and measurement of basic sediments and water (BSW) content. The crude oil was treated in a dielectric barrier discharge plasma reactor, using natural gas, CO2 or H-2 as working gas. The results indicated a large drop in the water content of the plasma-treated samples as compared to the crude oil, giving rise to a reduction in the viscosity. No significant chemical change was produced in the oil portion itself, as observed by H-1 NMR. The water contents determined by H-1 low-field NMR analyses agreed well with those obtained by BSW, indicating the low-field NMR methods as a useful tool for following the effects of plasma treatments on heavy oils, allowing the separation of the effects caused on the water and oil fractions. (C) 2011 Elsevier Ltd. All rights reserved.

Flow injection analysis of free glycerol in biodiesel using a copper electrode as an amperometric detector

The main goal of this work was to develop a simple analytical method for quantification of glycerol based on the electrocatalytic oxidation of glycerol on the copper surface adapted in a flow injection system. Under optimal experimental conditions, the peak current response increases linearly with glycerol concentration over the range 60-3200 mg kg(-1) (equivalent to 3-160 mg L(-1) in solution). The repeatability of the electrode response in the flow injection analysis (FIA) configuration was evaluated as 5% (n = 10), and the detection limit of the method was estimated to be 5 mg kg(-1) in biodiesel (equivalent to 250 mu g L(-1) in solution) (S/N = 3). The sample throughput under optimised conditions was estimated to be 90 h(-1). Different types of biodiesel samples (B100), as in the types of vegetable oils or animal fats used to produce the fuels, were analysed (seven samples). The only sample pre-treatment used was an extraction of glycerol from the biodiesel sample containing a ratio of 5 mL of water to 250 mg of biodiesel. The proposed method improves the analytical parameters obtained by other electroanalytical methods for quantification of glycerol in biodiesel samples, and its accuracy was evaluated using a spike-and-recovery assay, where all the biodiesel samples used obtained admissible values according to the Association of Official Analytical Chemists. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.

Determination of the activation energies of beef tallow and crude glycerin combustion using thermogravimetry

The present study deals with the determination of the activation energy for the thermal decomposition of two renewable fuels crude glycerin and beef tallow. The activation energies were investigated by using a thermogravimetric analyzer (TGA) in the temperature range of 25-600 degrees C in atmosphere of synthetic air. The TG curves of the thermal decomposition process of both samples were divided into several phases and the second, called PH2, was chosen for the kinetic study because it is associated with the combustion ignition. Differential Thermal Analysis (DTA) showed an endothermic event at the PH2 region for the crude glycerin corresponding to devolatilization, while for beef tallow, this step presented an exothermic event, called LTO (low-temperature oxidation), which is correlated with devolatilization followed by combustion. For the entire PH2, activation energy values for crude glycerin were between 90 kJ mol(-1) and 42 kJ mol(-1), while for the beef tallow they ranged from 50 kJ mol(-1) to 113 kJ mol (1). The activation energy values obtained at the pre-ignition stage - conversion between 0 and 0.45 - showed that the crude glycerin with higher values requires an additional energetic support at the start of combustion processes and the beef tallow ignites more easily, presenting lower values. According to the Wolfer's equation, a direct relation between the activation energy and the ignition delay is established and the results of this study provides useful data for the development and design of new combustion chambers and engines when non-traditional fuels are used as feedstock. (C) 2012 Elsevier Ltd. All rights reserved.