Estudi de la fotodescomposició de l'àcid 4-clor-2-metilfenoxiacètic (MCPA)

Photodegradation of MCPA in aqueous solutions has been studied using UN. radiation and simulated sunlight with sensitizers. The main photoproducts have been characterized and a possible sequence of hotodecomposition leas been postulated. The kinetic study has been carried out in both processes for initial reaction times. It has been proved that the riboflavine, contained in husk rice is one of the most effective sensitizers to degrade MCPA

Combining aldolases and transaminases for the synthesis of 2‑amino-4-hydroxybutanoic acid

Amino acids are of paramount importance as chiral building blocks of life, for drug development in modern medicinal chemistry, and for the manufacture of industrial products. In this work, the stereoselective synthesis of (S)- and (R)-2-amino-4-hydroxybutanoic acid was accomplished using a systems biocatalysis approach comprising a biocatalytic one-pot cyclic cascade by coupling of an aldol reaction with an ensuing stereoselective transamination. A class II pyruvate aldolase from E. coli, expressed as a soluble fusion protein, in tandem with either an S- or R-selective, pyridoxal phosphate dependent transaminase was used as a catalyst to realize the conversion, with formaldehyde and alanine being the sole starting materials. Interestingly, the class II pyruvate aldolase was found to tolerate formaldehyde concentrations of up to 1.4 M. The cascade system was found to reach product concentrations for (S)- or (R)-2-amino-4-hydroxybutanoic acid of at least 0.4 M, rendering yields between 86% and >95%, respectively, productivities of >80 g L–1 d–1, and ee values of >99%.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 635595 (CarbaZymes), the Ministerio de Economía y Competitividad (MINECO), the Fondo Europeo de Desarrollo Regional (FEDER) (grant no. CTQ2015-63563-R to P.C.), and COST action CM1303 Systems Biocatalysis.We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).Peer reviewe

D-Fagomine lowers postprandial blood glucose and modulates bacterial adhesion

d-Fagomine is an iminosugar originally isolated from seeds of buckwheat (Fagopyrum sculentum Moench), present in the human diet and now available as a pure crystalline product. We tested d-fagomine for activities connected to a reduction in the risk of developing insulin resistance, becoming overweight and suffering from an excess of potentially pathogenic bacteria. The activities were: intestinal sucrase inhibition in vitro (rat mucosa and everted intestine sleeves), modulation of postprandial blood glucose in rats, bacterial agglutination and bacterial adhesion to pig intestinal mucosa. When ingested together with sucrose or starch, d-fagomine lowered blood glucose in a dose-dependent manner without stimulating insulin secretion. d-Fagomine reduced the area under the curve (0-120 min) by 20 % (P < 0•01) and shifted the time to maximum blood glucose concentration (T max) by 15 min at doses of 1-2 mg/kg body weight when administered together with 1 g sucrose/kg body weight. Moreover, d-fagomine (0•14 mm) agglutinated 60 % of Enterobacteriaceae (Escherichia coli, Salmonella enterica serovar Typhimurium) populations (P < 0•01), while it did not show this effect on Bifidobacterium spp. or Lactobacillus spp. At the same concentration, d-fagomine significantly (P < 0•001) inhibited the adhesion of Enterobacteriaceae (95-99 % cells in the supernatant) and promoted the adhesion of Lactobacillus acidophilus (56 % cells in the supernatant) to intestinal mucosa. d-Fagomine did not show any effect on bacterial cell viability. Based on all this evidence, d-fagomine may be used as a dietary ingredient or functional food component to reduce the health risks associated with an excessive intake of fast-digestible carbohydrates, or an excess of potentially pathogenic bacteria. © 2011 The Authors

Procedimiento de purificación de aminoácidos glicosilados aptos para la síntesis en fase sólida de glicopéptidos

Fecha de presentación nacional 28.08.1995.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC).Durante las reacciones de glicosidación de aminoácidos se obtienen conjugados entre aminoácidos y azúcar (sintones glicosilados) que es necesario purificar. Para ello se utiliza simple agua desionizada en la purificación por cromatografía en fase reversa a nivel preparativo. El procedimiento de la invención permite disponer de cantidades del orden de gramos de los mencionados sintones glicosilados purificados lo que es crucial para el desarrollo de glicop_eptidos con actividad biológica como posibles fármacos. Por tanto el procedimiento es de interés principalmente para el sector farmacéutico así como para el mercado de derivados para la investigación sobre compuestos bioactivos.Peer reviewe

Lipase-catalysed selective monoacylation of 1,n-diols with vinyl acetate

3 pages, 1 figure, 2 tables.-- Printed version published Jun 21, 2004.A simple enzymatic methodology for the selective monoacetylation of 1,n-diols (n=5,8) using vinyl acetate is reported. Monoacetylation excesses of 81–87% at 74–90% 1,n-diol conversions were obtained in toluene and diisopropyl ether using Thermomyces lanuginosus lipase (TLL) immobilised on polypropylene powder as catalyst.A simple enzymatic methodology for the selective monoacetylation of 1,n-diols (n=5,8) using immobilised Thermomyces lanuginosus lipase in different organic media is reported.We gratefully acknowledge CICYT (AGL2001-0585) and Generalitat de Catalunya (2001SGR 00342) for financial support.Peer reviewe

Amino acid-based surfactants: Enzymatic synthesis, properties and potential applications

Amino acid-based surfactants constitute a class of bio-based surfactants with excellent adsorption and aggregation properties, low potential toxicity and broad biological activity. In this review, the enzymatic synthesis, physicochemical and biological properties as well as the potential uses of these compounds are described.Peer reviewe

Protein flexibility and metal coordination changes in DHAP-dependent aldolases

7 pages, 5 figures, 2 tables.-- PMID: 19115296 [PubMed].-- Available online Dec 29, 2008.The mobility of rhamnulose-1-phosphate aldolase (RhuA) was analysed with a normal mode description and high level calculations on models of the active site. We report the connection between the mobility and the chemical properties of the active site, and compare them to a closely related enzyme, fuculose-1-phosphate aldolase (FucA). Calculations show that the different coordination number for the zinc ion, reported in the crystal structures of RhuA and FucA, was due to a different spatial arrangement of the residues, not to their different chemical nature. Moreover, the metal coordination change is correlated with activity. The domain mobility of the enzyme can reshape the active site of RhuA into the arrangement found in the FucA structure, and vice-versa. This has a direct influence on the energy barrier for the aldol reaction catalyzed by these enzymes, thus showing a coupling of the domain movements and the catalytic effects. Hence domain movements and the coordination chemistry of the active site metal suggest an explanation of why these enzymes have similar experimental turnover rates.R.C. thanks the Spanish Ramón y Cajal Program for financial support, and A.J. thanks the CSIC and the European Social Fund for her I3P fellowship. We acknowledge financial support from the MEC (Grant CTQ2006–01345/BQU) and the Generalitat de Catalunya (Grant 2005SGR00111). This research has been partly performed by using the CESCA resources.Peer reviewe

Chemo-enzymatic synthesis of arginine-based gemini surfactants

A novel chemo-enzymatic synthesis of arginine-based gemini cationic surfactants bis(Args) is reported. These compounds consist of two single Nα-acyl-arginine structures connected through the alfa-carboxylic groups of the arginine residues by a α,ω-diaminoalkane spacer chain. Nα-Acyl-L-arginine alkyl ester derivatives were the starting building blocks for the synthesis. The best strategy found consisted of two steps. First, the quantitative acylation of one amino group of the spacer by the carboxylic ester of the Nα-acyl-arginine took place spontaneously, at the melting point of the α,ω-diaminoalkane, in a solvent-free system. The second step was the papain-catalyzed reaction between another Nα-acyl-arginine alkyl ester and the free aliphatic amino group of the derivative formed in the first step. Reactions were carried out in solid-to-solid and solution systems using low-toxic potential solvents. Changes in reaction performance and product yield were studied for the following variables: organic solvent, support for enzyme deposition and substrate concentration. The best yields (70%) were achieved in solid-to-solid systems and in ethanol at aw = 0.07. Bis(Args) analogs of 8, 10 and 12 carbon atoms using 1,3-diaminopropane and 1,3-diamino-2-hydroxy-propane as hydrocarbon spacers were prepared at the 6–7 gram level employing the methodology developed. The overall yields which include reaction and purification varied from 51% to 65% of pure (97–98% by HPLC) product.Peer reviewe

Procedimiento quimioenzimático para la preparación de iminociclitoles

Traducción de patente europea publicada el 11JUN2010. Titulares: Consejo Superior de Investigaciones Científicas (CSIC) y Bioglane S.L.N.E.La presente invención se refiere a un procedimiento quimioenzimático para la preparación de iminociclitoles. Los productos sintetizados se pueden usar como complementos dietéticos e ingredientes funcionales en la industria alimenticia, así como agentes terapéuticos (p. ej., en el tratamiento de diabetes).Peer reviewedConsejo Superior de Investigaciones Científicas (España), Bioglane SLNET3 Traducción de patente europe

Derivados de amida de ácidos grasos con anfetaminas para el tratamiento de desórdenes alimenticios

La presente invención se refiere a nuevos derivados amidas de ácidos grasos conjugados con anfetaminas, que se comportan como ligandos duales de los receptores cannabionides tipo 1 (CB 1) Y del subtipo alfa de los receptores activados por el proliferador de peroxisomas (PPARalfa), y como potentes agentes inhibidores de la oxidación de la Lipoproteína de Baja Densidad (LDL), así como a su procedimiento de preparación, y su utilización como herramienta farmacológica y como fármacos para modular las acciones reguladas por los citados receptores, como la inducción de la saciedad y control de ingesta, la disminución de la grasa corporal y la regulación del metabolismo lipídico.Peer reviewedFundación IMIM, Fundación IMABIS-Instituto Mediterráneo para el Avance de la Biotecnología y la Investigación Sanitaria, Consejo Superior de Investigaciones Científicas (España) (CSIC) (Titular al 10%)A1 Solicitud de patente con informe sobre el estado de la técnic