Zinc supplementation alters tissue distribution of arsenic in Mus musculus.

Arsenic occurs naturally in the environment and humans can be exposed through food, drinking water and inhalation of air-borne particles. Arsenic exposure is associated with cardiovascular, pulmonary, renal, immunologic, and developmental toxicities as well as carcinogenesis. Arsenic displays dose-depen toxicities in target organs or tissues with elevated levels of arsenic. Zinc is an essential micronutrient with proposed protective benefits due to its antioxidant properties, integration into zinc-containing proteins and zinc-related immune signaling. In this study, we tested levels of arsenic and zinc in plasma, kidney, liver, and spleen as model tissues after chronic (42-day) treatment with either arsenite, zinc, or in combination. Arsenite exposure had minimal impact on tissue zinc levels with the exception of the kidney. Conversely, zinc supplementation of arsenite-exposed mice reduced the amount of arsenic detected in all tissues tested. Expression of transporters associated with zinc or arsenic influx and efflux were evaluated under each treatment condition. Significant effects of arsenite exposure on zinc transporter expression displayed tissue selectivity for liver and kidney, and was restricted to Zip10 and Zip14, respectively. Arsenite also interacted with zinc co-exposure for Zip10 expression in liver tissue. Pairwise comparisons show neither arsenite nor zinc supplementation alone significantly altered expression of transporters utilized by arsenic. However, significant interactions between arsenite and zinc were evident for Aqp7 and Mrp1 in a tissue selective manner. These findings illustrate interactions between arsenite and zinc leading to changes in tissue metal level and suggest a potential mechanism by which zinc may offer protection from arsenic toxicities.

Phosphorous-doped TiO2 nanoparticles: synthesis, characterization, and visible photocatalytic evaluation on sulfamethazine degradation.

Mesoporous phosphorous-doped TiO2 (TP) with different wt% of P (0.5, 1.0, and 1.5) was synthetized by microwave-assisted sol-gel method. The obtained materials were characterized by XRD with cell parameters refinement approach, Raman, BET-specific surface area analysis, SEM, ICP-OES, UV-Vis with diffuse reflectance, photoluminescence, FTIR, and XPS. The photocatalytic activity under visible light was evaluated on the degradation of sulfamethazine (SMTZ) at pH 8. The characterization of the phosphorous materials (TP) showed that incorporation of P in the lattice of TiO2 stabilizes the anatase crystalline phase, even increasing the annealing temperature. The mesoporous P-doped materials showed higher surface area and lower average crystallite size, band gap, and particle size; besides, more intense bands attributed to O-H bond were observed by FTIR analysis compared with bare TiO2. The P was substitutionally incorporated in the TiO2 lattice network as P5+ replacing Ti4+ to form Ti-O-P bonds and additionally present as PO43- on the TiO2 surface. All these characteristics explain the observed superior photocatalytic activity on degradation (100%) and mineralization (32%) of SMTZ under visible radiation by TP catalysts, especially for P-doped TiO2 1.0 wt% calcined at 450 °C (TP1.0-450). Ammonium, nitrate, and sulfate ions released during the photocatalytic degradation were quantified by ion chromatography; the nitrogen and sulfur mass balance evidenced the partial mineralization of this recalcitrant molecule.

Traditional uses, conservation status and biotechnological advances for a group of aromatic / medicinal native plants from America / Usos tradicionales, estado de conservación y avances biotecnológicos para un grupo de plantas aromáticas / medicinales nativas de América

Medicinal and aromatic plants are biologically and economically valuable species because of their intrinsic value as plants, ability to produce secondary metabolites, possible use in the pharmaceutical and food industries, germplasm availability and applications in traditional medicine. In addition, they hold social and economic importance due to the ancestral knowledge they represent and because they are part of the livelihood of many families. Most of them are collected from the wild and are in serious danger of extinction. Through biotechnological tools it is possible to develop their germplasm and obtain new and improved varieties from wild material, while advocating the alternative of production by cultivation instead of extracting it from nature. The objective of this review is to provide an updated perspective on the traditional uses, conservation status and biotechnological advances in a group of 30 plant species native to the American continent.

Las plantas medicinales y aromáticas deben ser valoradas tanto por su valor intrínseco como tales, por su capacidad de producir metabolitos secundarios, su posible uso en las industrias farmacéutica y alimentaria y por sus aplicaciones en medicina tradicional. Además, tienen importancia social y económica debido al conocimiento ancestral que representan y porque son parte del sustento de muchas familias. La mayoría de estas especies son recolectadas de la naturaleza y están en grave peligro de extinción. A través de herramientas biotecnológicas es posible desarrollar su germoplasma y obtener variedades nuevas y mejoradas a partir de material silvestre; esta estrategia propicia la alternativa de producción por cultivo en lugar de extraerla de la naturaleza. El objetivo de esta revisión es proporcionar una perspectiva actualizada de los usos tradicionales, el estado de conservación y los avances biotecnológicos en un grupo de 30 especies de plantas nativas del continente americano.

Essential oil characterization of two Azorean Cryptomeria japonica populations and their biological evaluations.

Essential oils from foliage, bark and heartwood of Cryptomeriajaponica D. Don from Azores Archipelago (Portugal) were analyzed by GC and GC-MS. Two populations, of black and reddish heartwood color, were studied. The main compounds found in the foliage of both populations were alpha-pinene (9.6-29.5%), (+)-phyllocladene (3.5-26.5%), ent-kaur-16-ene (0.2-20.6%), sabinene (0.5-19.9%) and limonene (1.4-11.5%), with a large variation in individual compounds from each population. Heartwood oils were characterized by a high content of cubebol (2.8-39.9%) and epi-cubebol (4.1-26.9%) isomers, which were absent in the foliage. Elemol and eudesmol isomers were found in the foliage and heartwood oils, while (+)-phyllocladene was absent in heartwood. Black and reddish bark oils were composed of the diterpenes dehydroferruginol (1.9-5.1%) and ferruginol (2.6-11.5%), along with the sesquiterpenes delta-cadinene (10.4-15.9%), alpha-muurolene (3.3-5.4%), epi-zonarene (4.0-5.0%), cubenol (9.3-14.0%), tau-muurolol (4.8-10.7%), beta-eudesmol (3.0-9.9%), gamma-eudesmol (1.9-7.0%) and hedycariol (1.4-6.2%). Azorean C. japonica oils exhibited significant chemical differences compared with native plants from Asia. The essential oils showed moderate antimicrobial activity against the pathogenic fungus Cryptococcus neoformans and human pathogenic bacteria (especially against multidrug-resistant Mycobacterium tuberculosis). The antimicrobial activity of the essential oils may be attributed to compounds such as ent-kaur-16-ene, (+)-phyllocladene, ferruginol and elemol, which are present in different proportions within the complex oil mixture. These results suggest a potential use for C. japonica oils obtained from wood industry leftovers.

Antifungal activity of sakurasosaponin from the root extract of Jacquinia flammea.

The methanolic crude extract from the roots of Jacquinia flammea showed moderate antifungal activity against dermatophytes and very strong antifungal activity against Colletotrichum gloeosporioides. The bioassay-guided purification of the extract, using a combination of vacuum-liquid chromatography and high performance liquid chromatography, allowed the identification of sakurasosaponin as the main metabolite responsible for the antifungal activity.

Membrane-targeted synergistic activity of docosahexaenoic acid and lysozyme against Pseudomonas aeruginosa.

Antimicrobial polypeptides, including lysozymes, have membrane perturbing activity and are well-documented effector molecules of innate immunity. In cystic fibrosis, a hereditary disease with frequent lung infection with Pseudomonas aeruginosa, the non-esterified fatty acid DA (docosahexaenoic acid), but not OA (oleic acid), is decreased, and DA supplementation has been shown to improve the clinical condition in these patients. We hypothesized that DA may, either alone or in conjunction with lysozyme, exert antibacterial action against Ps. aeruginosa. We found that DA and lysozyme synergistically inhibit the metabolic activity of Ps. aeruginosa, in contrast with OA. Electron microscopy and equilibrium dialysis suggest that DA accumulates in the bacterial membrane in the presence of lysozyme. Surface plasmon resonance with live bacteria and differential scanning calorimetry studies with bacterial model membranes reveal that, initially, DA facilitates lysozyme incorporation into the membrane, which in turn allows influx of more DA, leading to bacterial cell death. The present study elucidates a molecular basis for the synergistic action of non-esterified fatty acids and antimicrobial polypeptides, which may be dysfunctional in cystic fibrosis.

Antifungal activity of Zuccagnia punctata Cav.: evidence for the mechanism of action.

Petroleum ether and dichloromethane extracts of fruits, aerial parts and exudate of Zuccagnia punctata Cav. (Fabaceae) showed moderate antifungal activities against the yeasts C. albicans, S. cerevisiae and C. neoformans (MICs: 62.5 - 250 microg/mL) and very strong antifungal activities against the dermatophytes M. gypseum, T. rubrum and T. mentagrophytes (MICs: 8 - 16 microg/mL) thus supporting the ethnopharmacological use of this plant. Antifungal activity-directed fractionation of active extracts by using bioautography led to the isolation of 2',4'-dihydroxy-3'-methoxychalcone (1) and 2',4'-dihydroxychalcone (2) as the compounds responsible for the antifungal activity. Second-order studies included MIC (80), MIC (50) and MFC of both chalcones in an extended panel of clinical isolates of the most sensitive fungi, and also comprised a series of targeted assays. They showed that the most active chalcone 2 is fungicidal rather than fungistatic, does not disrupt the fungal membranes up to 4 x MFC and does not act by inhibiting the fungal cell wall. So, 2',4'-dihydroxychalcone would act by a different mechanism of action than the antifungal drugs in current clinical use, such as amphotericin B, azoles or echinocandins, and thus appears to be very promising as a novel antifungal agent.

Antifungal activity of some coumarins obtained from species of Pterocaulon (Asteraceae).

Fractionation of antifungal hexane extracts of the aerial parts of three Pterocaulon spp., Pterocaulon alopecuroides, Pterocaulon balansae and Pterocaulon polystachyum (Asteraceae) from South Brazil traditionally used to treat animal mycoses, afforded the coumarins 5-methoxy-6,7-methylenedioxycoumarin, 7-(2',3'-epoxy-3'-methylbutyloxy)-6-methoxycoumarin, 6,7-methylenedioxycoumarin (ayapin), along with a mixture of 6-hydroxy-7-(3'-methylbutyl-2'-en-oxy)-coumarin (prenyletin) and 6-methoxy-7-(3'-methylbutyl-2'-en-oxy)-coumarin (prenyletin-methyl-ether). Among the different components of the active extracts, only the mixture of prenyletin and prenyletin-methyl-ether isolated from Pterocaulon polystachyum showed activity against Cryptococcus neoformans, Microsporum gypseum, Trichophyton rubrum and Trichophyton mentagrophytes. Nevertheless their MIC values were higher than the MIC of the original extracts, suggesting that the mixture but not only one compound would be the responsible for the activity detected in these Pterocaulon species.