Immobilization of the white-rot fungus Anthracophyllum discolor to degrade the herbicide atrazine

Herbicides cause environmental concerns because they are toxic and accumulate in the environment, food products and water supplies. There is a need to develop safe, efficient and economical methods to remove them from the environment, often by biodegradation. Atrazine is such herbicide. White-rot fungi have the ability to degrade herbicides of potential utility. This study formulated a novel pelletized support to immobilize the white-rot fungus Anthracophyllum discolor to improve its capability to degrade the atrazine using a biopurification system (BS). Different proportions of sawdust, starch, corn meal and flaxseed were used to generate three pelletized supports (F1, F2 and F3). In addition, immobilization with coated and uncoated pelletized supports (CPS and UPS, respectively) was assessed. UPS-F1 was determined as the most effective system as it provided high level of manganese peroxidase activity and fungal viability. The half-life (t1/2) of atrazine decreased from 14 to 6 days for the control and inoculated samples respectively. Inoculation with immobilized A. discolor produced an increase in the fungal taxa assessed by DGGE and on phenoloxidase activity determined. The treatment improves atrazine degradation and reduces migration to surface and groundwater.Grant CONICYT/FONDAP/15130015Grant FONDECYT 112096

Efecto de la dieta rica en grasa (1%) sobre la aorta y el hígado en conejas ovariectomizadas. II parte

Cause more increased morbidity and mortality in the world. Atherosclerosis is a chronic inflammatory arterial injury exacerbated by an altered lipid metabolism and cardio-vascular risk factors. It was the interests of authors evaluate the effect of a high diet fat on specimen of aorta and liver in an animal model such as the rabbit. Material and Methods. 20 New Zealand rabbits were taken from 2500 to 3000 kg in weight which were divided into 2 groups: Group I (n = 10) 5 control (C), 5 control-fat diet + 1% (C+D) and group II (n = 10) ovariectomized, 5 control (O) and 5 high-fat diet with 1% (O+D). Was evaluated by ultrasonography the abdominal aorta. At the end of the 24 week was sacrificed a rabbit in each group to carried out histological studies of aorta and liver. Was used hematoxylin eosin staining and histological sections for high resolution and fat stain (Fast-Red) Results. In ultrasound the diameter of the aorta between the C and C+D grew by 18.40% in the O and O+D was 12.83%. The intima of the C and C+D grew by 33.33% and between O and O+D controls grew by 15.38%. 50% lower when comparing with controls. The evaluation of the intima between the C1 and O1 increased the diameter in a 14.72% and the thickness of the intima was 33.33%. In the case of C+O and O+D the diameter presented an increase of 0.33% and the adventitia was increased for 275.0%. Histology of the aorta and the hepatocyte shows that the C: had a little increase of fat granules in the intima and in the hepatocyte. C+D: the aorta were seen fat droplets in the intima with thickening of the intima (290 u-390 u). In the liver there was an inflammatory process with moderate hydropic changes and fat droplets inside. O: there was very little change in the intima, small lipid droplets and the diameter is slightly increased (180 u-240 u) compared with controls and inflammatory foci in the liver with hydropic degeneration and fat perilobulillar pericellular in relation to controls. O+D: the aorta showed a large accumulation of fat pericellular with increase in thickness (230 u-360 u) are little larger than the C+D, presents hepatocyte hydropic changes, severe vacuolization and fat perilobulillar strong reaction. Conclusion. The high-fat diet (1%) in a rabbit model produced severe injury to aortic endothelium and the hepatocyte, especially in rabbits with diet and to a lesser extent in the oophorectomised ones.Introducción. La enfermedad coronaria con la enfermedad cerebrovascular son las entidades que causan mayor morbilidad y mortalidad en el mundo. La ateroesclerosis es una lesión arterial inflamatoria crónica exacerbada por una alteración del metabolismo lipídico y factores de riesgo cardiovascular. Fue interés de los autores evaluar el efecto de una dieta rica en grasa sobre especímenes de aorta e hígado en un modelo animal como la coneja. Material y Métodos. Se tomaron 20 conejas New Zealand de 2.500 a 3.000 gr de peso,las cuales se dividieron en 4 grupos de 5 cada uno: grupo 1 n = 5 control (C1); grupo 2 n =5 control + dieta rica en grasa 1% (C+D); grupo 3 ovariectomizadas n = 5 control (O1) y grupo 4 n = 5 con dieta rica en grasa 1% (O+D). Se evaluó por estudio ecográfico la aorta abdominal y al final de las 24 semanas se sacrificó una coneja de cada uno de los 4 grupos, realizándose estudios histológicos de aorta y el hígado. Se utilizó la coloración de hematoxilina eosina, cortes histológicos para alta resolución y una coloración para grasa (Red Fast). Resultados. Ultrasonido de la aorta: el diámetro de la aorta se incrementó en un 18.40% en las conejas no ovariectomizadas y un 12.83% en las ovariectomizadas. La intima de los C y los C+D aumentó un 33.33% y entre las O controles y O+D aumentó un 15.38%, 50% menor al comprarla con los controles. La evaluación de la intima entre los C1 y O1 aumentó el diámetro en un 14.72% y el grosor de la intima fue del 33.33%. En los casos de C+O y O+D el diámetro presentó un aumento de 0.33% y la adventicia presentó un aumento de 275.0%. El estudio histológico de la aorta y el hepatocito muestra que las C: presentan un aumento escaso de gránulos de grasa en la intima y en el hepatocito; las C+D: en la aorta se aprecian pequeñas gotas de grasa en la intima con aumento del espesor de la intima (290 u-390 u). En el hígado se observa un proceso inflamatorio con alteraciones hidrópicas moderadas y gotas grasas en su interior; las O: se observan muy pocos cambios en la intima, escasas gotas de lípidos y el diámetro se encuentra ligeramente aumentado (180 u-240 u) en relación con los controles. En el hígado, focos inflamatorios con degeneración hidrópica perilobulillar y grasa pericelular; en las O+D: la aorta demuestra un gran acumulo de grasa pericelular con aumento en el espesor (230 u-360 u) un poco mayor que la C+D, el hepatocito presenta cambios hidrópicos, severa vasculización y marcada reacción grasa perilobulillar. Conclusión. La dieta rica en grasa (1%) en un modelo como el conejo produce lesiones severas a nivel del endotelio aórtico y el hepatocito, especialmente en las conejas con dieta y en menor proporción en las ooforectomizadas.Incluye referencias bibliográfica

Novelty and spatio–temporal heterogeneity in the bacterial diversity of hypersaline Lake Tebenquiche (Salar de Atacama)

14 pages, 7 figures, 3 tablesLake Tebenquiche is one of the largest saline water bodies in the Salar de Atacama at 2,500 m above sea level in northeastern Chile. Bacteria inhabiting there have to deal with extreme changes in salinity, temperature and UV dose (i.e., high environmental dissimilarity in the physical landscape). We analyzed the bacterioplankton structure of this lake by 16S rRNA gene analyses along a spatio–temporal survey. The bacterial assemblage within the lake was quite heterogeneous both in space and time. Salinity changed both in space and time ranging between 1 and 30% (w/v), and total abundances of planktonic prokaryotes in the different sampling points within the lake ranged between two and nine times 106 cells mL−1. Community composition changed accordingly to the particular salinity of each point as depicted by genetic fingerprinting analyses (denaturing gradient gel electrophoresis), showing a high level of variation in species composition from place to place (beta-diversity). Three selected sites were analyzed in more detail by clone libraries. We observed a predominance of Bacteroidetes (about one third of the clones) and Gammaproteobacteria (another third) with respect to all the other bacterial groups. The diversity of Bacteroidetes sequences was large and showed a remarkable degree of novelty. Bacteroidetes formed at least four clusters with no cultured relatives in databases and rather distantly related to any known 16S rRNA sequence. Within this phylum, a rich and diverse presence of Salinibacter relatives was found in the saltiest part of the lake. Lake Tebenquiche included several novel microorganisms of environmental importance and appeared as a large unexplored reservoir of unknown bacteriaSampling and measurements carried out in Chile were funded by grants FONDECYT 1030441 and FONDEF D99I1026. Measurements carried out in Barcelona were funded by grant "ATACAMA-2002" (CICYT, BOS2002-10258-E). Grant "BIOARSENICO" from Fundación BBVA funds current workPeer reviewe

A 2a adenosine receptor: Structures, modeling, and medicinal chemistry

Many selective agonists and antagonists of the A 2A adenosine receptor (AR) have been reported, while allosteric modulators specific for this receptor are still needed. Many heterocyclic chemotypes have been discovered as A 2A AR antagonists, while most of the known AR agonists are nucleosides or 3,5-dicyanopyridine derivatives. A few A 2A AR ligands have been in clinical trials as antihypertensives, anti-inflammatory or diagnostic compounds (agonists), and as drugs for treating Parkinson’s disease and cancer (antagonists). The A 2A AR has become one of the most widely investigated G protein-coupled receptor (GPCR) structures using X-ray crystallography and also biophysical techniques such as NMR. Thus, the design of agonists, antagonists, and allosteric modulators has become structure-based, with numerous examples of in silico approaches, including virtual ligand screening (VLS), leading to the discovery of both novel agonists and antagonists

Implications of new research and technologies for malolactic fermentation in wine

The initial conversion of grape must to wine is an alcoholic fermentation (AF) largely carried out by one or more strains of yeast, typically Saccharomyces cerevisiae. After the AF, a secondary or malolactic fermentation (MLF) which is carried out by lactic acid bacteria (LAB) is often undertaken. The MLF involves the bioconversion of malic acid to lactic acid and carbon dioxide. The ability to metabolise L-malic acid is strain specific, and both individual Oenococcus oeni strains and other LAB strains vary in their ability to efficiently carry out MLF. Aside from impacts on acidity, LAB can also metabolise other precursors present in wine during fermentation and, therefore, alter the chemical composition of the wine resulting in an increased complexity of wine aroma and flavour. Recent research has focused on three main areas: enzymatic changes during MLF, safety of the final product and mechanisms of stress resistance. This review summarises the latest research and technological advances in the rapidly evolving study of MLF and investigates the directions that future research may take.Krista M. Sumby, Paul R. Grbin, Vladimir Jirane