Marili Villa Nova Rodrigues

Marine-derived filamentous fungi and their potential application for polycyclic aromatic hydrocarbon bioremediation.

Eight marine-derived fungi that were previously selected for their abilities to decolorize RBBR dye were subjected to pyrene and benzo[a]pyrene degradation. The fungus Aspergillus sclerotiorum CBMAI 849 showed the best performance with regard to pyrene (99.7%) and benzo[a]pyrene (76.6%) depletion after 8 and 16 days, respectively. Substantial amounts of benzo[a]pyrene (>50.0%) depletion were also achieved by Mucor racemosus CBMAI 847. Therefore, these two fungal strains were subjected to metabolism evaluation using the HPLC-DAD-MS technique. The results showed that A. sclerotiorum CBMAI 849 and M. racemosus CBMAI 847 were able to metabolize pyrene to the corresponding pyrenylsulfate and were able to metabolize benzo[a]pyrene to benzo[a]pyrenylsulfate, suggesting that the mechanism of hydroxylation is mediated by a cytochrome P-450 monooxygenase, followed by conjugation with sulfate ions. Because these fungi were adapted to the marine environment, the strains that were used in the present study are considered to be attractive targets for the bioremediation of saline environments, such as ocean and marine sediments that are contaminated by PAHs.

9-Benzoyl 9-deazaguanines as potent xanthine oxidase inhibitors

A novel potent xanthine oxidase inhibitor, 3-nitrobenzoyl 9-deazaguanine (LSPN451), was selected from a series of 10 synthetic derivatives. The enzymatic assays were carried out using an on-flow bidimensional liquid chromatography (2D LC) system, which allowed the screening¸ the measurement of the kinetic inhibition constant and the characterization of the inhibition mode. This compound showed a non-competitive inhibition mechanism with more affinity for the enzyme-substrate complex than for the free enzyme, and inhibition constant of 55.1±9.80 nM, about thirty times more potent than allopurinol. Further details of synthesis and enzymatic studies are presented herein.

Improved extraction method to evaluate the degradation of selected PAHs by marine fungi grown in fermentative medium

An improved method to evaluate the degradation of polycyclic aromatic hydrocarbons (PAHs) for filamentous fungi is hereby proposed. The PAH adsorption through fungal mycelia implies the use of an exhaustive extraction, which is usually performed through a combination of different techniques applied separately to the liquid medium and to the mycelia. This work proposes a simplified extraction procedure with reduced analysis time and sample manipulation, thereby guaranteeing its precision and accuracy. The selected PAHs, pyrene and benzo[a]pyrene, were quantified by gas chromatography using a mass selective detector operating in single ion monitoring mode. The method was validated presenting accuracy within the scope of this study and it was used for evaluating the potential of PAHs degradation by thirteen fungi derived from marine environment. This study selected the fungus Aspergillus sclerotiorum CBMAI 849 for being able to degrade 85% of pyrene and 61% of benzo[a]pyrene after 4 and 8 days, respectively, and the fungus Mucor racemosus CBMAI 847 for being able to degrade 44% of benzo[a]pyrene after 8 days

Produção de xarope de açúcar invertido obtido por hidrólise heterogênea, através de planejamento experimental

The use of liquid sugar in the food industry constitutes a great advantage in applications where the sugar is added in solution. The invert syrup gathers the high solubility of the frutose to the difficult crystallization of the glucose, increasing its sweetness and decreasing the crystallization risks. Those properties contribute to increase the value of those syrups for use in several products, above all in the industry of soft drinks. The objective of this work was improve the stages of invert syrup production using ion exchange resins, seeking to obtain a final product of high quality that assists to the needs of the industry of soft drinks using the experimental design. The production of inverted syrup began with sucrose decolorization process employing two anionic resins columns and subsequent elution through a cationic resin column, which promoted sucrose hydrolysis until inversion level desired. The obtained product was exempted practically of any objection to the palate, scentless, low levels of color (56 ICUMSA) and HMF (11 ppm). Determination of molds, yeasts and bacteria were smaller than 1 unit/mL.

Essential oils from Baccharis species (Asteraceae) have anti-inflammatory effects for human cells

Constituents of the essential oils from the aerial parts of Baccharis articulata (Ba), Baccharis genistelloides subsp. crispa (Bc), Baccharis dracunculifolia (Bd) and Baccharis gaudichaudiana (Bg), Asteraceae, obtained by hydrodistillation and analyzed by gas chromatography (GC)/mass spectrometry (MS) and GC/flame ionization detector (FID) were identified. Also, their anti-inflammatory potential, focusing their immunomodulatory activity using flow cytometric analyses and AgNOR profiles, and anti-chemotactic properties, conducted using a Boyden’s chamber system, were investigated. Fifty-eight compounds were characterized, representing 66.7% of the total components detected. The major constituents identified were spathulenol (in Ba, Bd and Bg), τ-gurjunene (in Bg) and palustrol (in Ba). The data presented herein showed that the Baccharis essential oils included in this study were inert for human resting lymphocytes, while all but Ba’s inhibited significantly the proliferation of their phytohemagglutinin-stimulated counterparts. In addition, only the essential oil of Bd inhibited significantly the casein-induced human granulocyte chemotaxis. This is the first report concerning the potential diversity of anti-inflammatory activities of the essential oils of Baccharis plants on human cells responsible for the host defense mechanisms that may be of benefit in intervening with immune disorders associated or not with inflammatory conditions.

Characterization and screening of tight binding inhibitors of xanthine oxidase: an on-flow assay

Xanthine oxidase (XO) is an enzyme in the purine salvage pathway that catalyzes the oxidation of hypoxanthine to xanthine with subsequent production of uric acid from the xanthine oxidation, and it has been considered an important target of newly developed inhibitors. Based on the advantages of using immobilized capillary enzyme reactors (ICERs) in a 2D LC system as a tool for screening new enzymatic ligands, this work validated an XO-ICER using allopurinol as a positive control. Despite the complex interaction between XO and allopurinol due its tight binding nature, it was possible to recognize the inhibitory kinetics parameters through Morrisons equation. The tight binding nature of inhibition was established by varying the IC50 values according to the substrate concentration. The kinetic inhibitory profile of allopurinol was used to validate the XO-ICER. Then, the XO-ICER was used to screen specific ruthenium derivatives. The selected compound, 4CBALO, an allopurinol ruthenium derivative, exhibited 100% inhibition at 200 μM compared to 86% inhibition from allopurinol at the same concentration. The inhibitory effect on the immobilized XO was reversible after the elution of the compound, with immediate recovery of the ICER activity. Additionally, 4CBALO behaved as a selective and competitive tight binder of xanthine oxidase with a true Ki value of 0.29 μM, which was obtained from the Morrison equation. This report describes the first on-flow characterization of tight binders of xanthine oxidase.

Deltamethrin and Permethrin in the liver and heart of Wistar rats submitted to oral subchronic exposure

For 28 days male Wistar rats were submitted to oral exposure with 1/10 of the LD50 value of permethrin (PMT) or deltamethrin (DMT). The aim of this study was to determine the residues of PMT and DMT in the liver and heart of the rats at the end of the exposure period, as well as to evaluate the effect of ingesting pectin and cellulose via the diet. The analytes were extracted with acetonitrile and the extracts were cleaned up by solid phase extraction with florisil before GC-ECD (gas chromatography coupled with an electron-capture detector) analysis. For PMT, the limits of quantitation (LOQ) were 1.0 and 0.2 µg g-1 and for DMT 0.9 and 0.2 µg g-1 for liver and heart, respectively. No PMT or DMT residues were verified above the LOQ of the method in either the liver or heart of the exposed animals

Docosahexaenoic acid ethyl esther (DHAEE) microcapsule production by spray-drying: optimization by experimental design

O acido docoso-hexaenoico e um acido graxo poli-insaturado essencial que desempenha importantes acoes metabolicas. Entretanto, por possuir duplas ligacoes conjugadas torna-se suscetivel a decomposicao. Uma das formas de minimizar esta possivel decomposicao e o emprego da tecnica de atomizacao para microencapsulacao. Porem, esta tecnica envolve uma serie de parâmetros de processo, que podem vir a alterar a qualidade do produto final. Assim, o objetivo deste trabalho foi microencapsular oleo de peixe enriquecido no ester etilico do acido docoso-hexaenoico (DHAEE-85%), variando condicoes operacionais e avaliar o rendimento pela analise por cromatografia gasosa, apos extracao das microcapsulas. Para tanto, foi utilizado o processo de microencapsulacao por atomizacao e o agente encapsulante foi a goma arabica. A avaliacao cromatografica de varios experimentos delineados pelo software Statistica, mostrou que os pontos otimos para obtencao das microcapsulas de DHAEE foram: temperatura de entrada 188 °C, porcentagem de recheio 30%, vazao de nitrogenio 55 mm N2 e vazao da bomba de 12,5 mL/minuto. Estas condicoes de processo foram testadas experimentalmente, resultando no teor de 66% m/m de DHAEE no oleo extraido, valor correspondente a 19,8% m/m de DHAEE encapsulado, valor considerado satisfatorio uma vez que 30% das microcapsulas correspondiam teoricamente ao material de parede.

Study of the Variation of the Composition of the Essential Oil of Leaves and Flowers of Achyrocline alata (D.C.) Along a Period of the Day

Abstract Leaves and flowers of Achyrocline alata were picked in an experimental garden throughout the period of 7 AM until 2 PM, in hourly intervals. The leaf and flower oils were obtained by hydrodistillation. Analyses of the oils by GC/MS reveals that the main components of the leaf oil varied as follows: α-pinene (1.7–7.6%), 1-octen-3-ol (1.7–5.6%), 1,8-cineole (0.4–5.1%), β-caryophyllene (14.6–16.7%), α-humulene (20.6–25.1%) and bicyclogermacrene (7.3–12.4%). The flower oil also varied—α-pinene (5.4–21.9%), 1-octen-3-ol (8.0–11.6%), 1, 8-cineole (7.3–10.9%), β-caryophyllene (12.0–17.5%), α-humulene (17.2–22.8%) and bicyclogermacrene (5.8–8.3%)—throughout the 8-h period.

Dosagem de artemisinina em Artemisia annua L. por cromatografia líquida de alta eficiência com detecção por índice de refração

Artemisinin is a sesquiterpene lactone used in treatment of chloroquine-resistant malaria. This paper presents high-performance liquid chromatographic assay for artemisinin in leaves of A. annua using differential refractometer detector and a single step of clean-up in a silica cartridge. The average of recoveries were 95% and the limit of quantification was 0,21% p/p using 200 mg of the leaves. This method was found to be simple, robust and relatively rapid.