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1.
Chembiochem ; 25(2): e202300627, 2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-37947295

RESUMEN

Antibiotics are micropollutants accumulating in our rivers and wastewaters, potentially leading to bacterial antibiotic resistance, a worldwide problem to which there is no current solution. Here, we have developed an environmentally friendly two-step process to transform the antibiotic rifampicin (RIF) into non-antimicrobial compounds. The process involves an enzymatic oxidation step by the bacterial CotA-laccase and a hydrogen peroxide bleaching step. NMR identified rifampicin quinone as the main product of the enzymatic oxidation. Growth of Escherichia coli strains in the presence of final degradation products (FP) and minimum inhibitory concentration (MIC) measurements confirmed that FP are non-anti-microbial compounds, and bioassays suggest that FP is not toxic to eukaryotic organisms. Moreover, competitive fitness assays between susceptible and RIF-resistant bacteria show that susceptible bacteria is strongly favoured in the presence of FP. Our results show that we have developed a robust and environmentally friendly process to effectively remediate rifampicin from antibiotic contaminated environments.


Asunto(s)
Peróxido de Hidrógeno , Lacasa , Lacasa/química , Peróxido de Hidrógeno/metabolismo , Rifampin/farmacología , Rifampin/metabolismo , Escherichia coli/metabolismo , Antibacterianos/farmacología , Antibacterianos/metabolismo
2.
Cogn Process ; 24(1): 43-57, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36242672

RESUMEN

Faces are fundamental stimuli for social interactions since they provide significant information about people's identity and emotional states. With the outburst of the COVID-19 pandemic, global use of preventive measures, such as disposable surgical face masks (DSFMs), has been imposed. The massive use of DSFMs covering a large part of the face could interfere with identity and emotion recognition. Thus, the main aim of the current study was (i) to assess how DSFMs affect identity recognition (Experiment 1), (ii) how DSFMs affect emotion recognition (Experiment 2), and (iii) whether individual empathy levels correlate with emotion recognition with DSFMs. The potential relation between identity and emotion recognition with and without DSFMs was also investigated. Two tasks were administered to 101 healthy participants: (i) the Old-new face memory task aimed to assess whether the learning context (i.e., DSFMs on/off) affects recognition performance, whereas (ii) the Facial affect task explored DSFMs' effect on emotion recognition. Results from the former showed that the stimuli's features in the learning stage affect recognition performances; that is, faces wearing DSFMs were better recognized if wearing DSFMs at first exposure and vice versa. Results from the Facial affect task showed that DSFMs lead to reduced disgust, happiness, and sadness recognition. No significant correlation emerged between identity and emotion recognition. The Interpersonal Reactivity Index (IRI) was administered to assess affective and cognitive empathy; however, IRI scores did not correlate with either face memory recognition or facial affect recognition. Overall, our results demonstrate (a) a "context effect" for face memory with and without DSFMs; (b) a disruptive effect of DSFMs depending on the expressed emotion; and (c) no correlation between empathy and emotion recognition with DSFMs.


Asunto(s)
COVID-19 , Reconocimiento Facial , Humanos , Máscaras , Pandemias , Emociones , Expresión Facial
3.
Chirality ; 34(5): 782-795, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35166402

RESUMEN

Novel 1,3-diamine-derived bifunctional thiourea and squaramide organocatalysts were synthesized from (+)-camphoric acid. These catalysts were easily obtained in up to two to five synthetic steps, in a flexible approach that facilitates their structure variation. Their catalytic activity was examined in the asymmetric Michael addition of 1,3-dicarbonyl compounds to several trans-ß-nitrostyrenes. Yields up to 98% and enantiomeric excesses up to 74% and high diastereoselectivities when applicable (dr up to 93:7) were obtained in these reactions showing that 1,3-diamine-derived bifunctional thioureas are efficient organocatalysts.


Asunto(s)
Alquenos , Diaminas , Alquenos/química , Estructura Molecular , Estereoisomerismo , Tiourea/química
4.
Proc Natl Acad Sci U S A ; 116(3): 835-844, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30606802

RESUMEN

Mycobacteria are a wide group of organisms that includes strict pathogens, such as Mycobacterium tuberculosis, as well as environmental species known as nontuberculous mycobacteria (NTM), some of which-namely Mycobacterium avium-are important opportunistic pathogens. In addition to a distinctive cell envelope mediating critical interactions with the host immune system and largely responsible for their formidable resistance to antimicrobials, mycobacteria synthesize rare intracellular polymethylated polysaccharides implicated in the modulation of fatty acid metabolism, thus critical players in cell envelope assembly. These are the 6-O-methylglucose lipopolysaccharides (MGLP) ubiquitously detected across the Mycobacterium genus, and the 3-O-methylmannose polysaccharides (MMP) identified only in NTM. The polymethylated nature of these polysaccharides renders the intervening methyltransferases essential for their optimal function. Although the knowledge of MGLP biogenesis is greater than that of MMP biosynthesis, the methyltransferases of both pathways remain uncharacterized. Here, we report the identification and characterization of a unique S-adenosyl-l-methionine-dependent sugar 1-O-methyltransferase (MeT1) from Mycobacterium hassiacum that specifically blocks the 1-OH position of 3,3'-di-O-methyl-4α-mannobiose, a probable early precursor of MMP, which we chemically synthesized. The high-resolution 3D structure of MeT1 in complex with its exhausted cofactor, S-adenosyl-l-homocysteine, together with mutagenesis studies and molecular docking simulations, unveiled the enzyme's reaction mechanism. The functional and structural properties of this unique sugar methyltransferase further our knowledge of MMP biosynthesis and provide important tools to dissect the role of MMP in NTM physiology and resilience.


Asunto(s)
Metilmanósidos/metabolismo , Metiltransferasas/metabolismo , Mycobacterium/metabolismo , Polisacáridos Bacterianos/biosíntesis , Dominio Catalítico , Metiltransferasas/genética , Familia de Multigenes , Mycobacterium/genética
5.
J Environ Manage ; 304: 114244, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34891053

RESUMEN

The feasibility of a Fenton-type process for the pretreatment of an oily refinery sludge has been explored taking advantage of the iron contained in the own sludge. This process reduces the content of total petroleum hydrocarbons (TPHs) accompanied by an increase in the total organic carbon concentration in the liquid phase. The effect of the temperature and the hydrogen peroxide loading was thoroughly studied in this work being the oxidant concentration the most critical parameter. Under 60 °C and 90 g/L of initial hydrogen peroxide concentration, the Total Organic Carbon (TOC) of the liquid phase was increased up values of 1336 mg/L and with a remarkable contribution of acetic acid as final oxidized compound (396 mgC/L). Additionally, nitrogen and phosphorous compounds were also dissolved in the aqueous phase achieving values of 250 mg/L and 7 mg/L for total Kjeldahl nitrogen and total phosphorous, respectively. Respirometry assays of the aqueous phase after the Fenton pretreatment have evidenced an increase of biodegradability up to 49% which makes this phase suitable for further biological processing in the refinery scheme. The reduction of the content of TPHs (61%) of the oily sludge, has also improved the settleability of the treated effluent (reducing the capillary suction time (CST) in ca. 88%).


Asunto(s)
Petróleo , Aguas del Alcantarillado , Hidrocarburos , Peróxido de Hidrógeno , Hierro , Aceites , Oxidación-Reducción
6.
J Environ Manage ; 285: 112124, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33592452

RESUMEN

Refinery treatment plants produce large quantities of oily sludge during the petroleum refining processes. The hazardousness associated with the disposal of these wastes, make necessary the development of innovative technologies to handle it adequately, linked to the concepts of circular economy and environmental sustainability. This work provides for the first time a methodology for the deep characterization of this kind of wastes and consequently new insights regarding its valorization. A review of works dealing with the characterization of this type of wastes has been addressed evidencing the complexity and variability of these effluents. The oily sludge under study contains a high concentration of Chemical Oxygen Demand of 196 g COD/L, a Total Kjeldahl Nitrogen of 2.8 g TKN/kg, a phosphorous content as PO43- of 7 g/kg, as well as a great presence of heavy metals in a different range of concentrations. This sludge is composed of three different phases: oily, aqueous and solid. The oily and the solid phases present high percentages of carbon content (84 and 26%, respectively), related to the presence of alkanes ranged from n-C9 to n-C44. Therefore, it could be possible their valorization by the synthesis of catalyst and/or adsorbents. A dark fermentation process could be also proposed for the oily phase to obtain H2 as an alternative energy source. Finally, the aqueous phase contains low carbon and nutrients concentration. A previous thermal pre-treatment applied to the oily sludge might increase nutrient and organic loading in the aqueous phase due to solid destruction, making this aqueous effluent suitable for a further conventional biological treatment.


Asunto(s)
Metales Pesados , Petróleo , Gasolina , Aceites , Aguas del Alcantarillado
7.
Molecules ; 26(2)2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33445716

RESUMEN

A new synthetic route for the quorum sensing signal Autoinducer-2 (AI-2) is described and used for the preparation of [4-13C]-AI-2 starting from [1-13C]-bromoacetic acid. The key step in this process was the enantioselective reduction of an intermediate ketone. This synthesis provides, selectively, both enantiomers of the labelled or unlabelled parent compound, (R) or (S)-4,5-dihydroxypentane-2,3-dione (DPD) and was used for an improved synthesis of [1-13C]-AI-2.


Asunto(s)
Homoserina/análogos & derivados , Lactonas/síntesis química , Lactonas/farmacología , Fenómenos Ópticos , Percepción de Quorum , Ciclización , Homoserina/síntesis química , Homoserina/farmacología , Percepción de Quorum/efectos de los fármacos
8.
Bioorg Chem ; 94: 103452, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31810755

RESUMEN

Histone deacetylases are involved in chromatin remodelling and thus play a vital role in the epigenetic regulation of gene expression. HDAC inhibitors alter the acetylation status of histone and non-histone proteins to regulate various cellular events such as transcription. Novel HDAC inhibitors were designed and synthesised to promote higher levels of recombinant protein production in tobacco cell cultures. The effect of these chemical enhancers on the epigenetic profiles in plant cells has been evaluated by molecular docking, in vitro and in vivo studies. The addition of these novel enhancers led to an increase in histone H3 acetylation levels that promoted an increase in the accumulation levels of the recombinant protein in cell culture. These results can pave the way for the application of these enhancers to improve the production of high value products in plant cell based systems.


Asunto(s)
Butiratos/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Nicotiana/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología , Butiratos/síntesis química , Butiratos/química , Células Cultivadas , Relación Dosis-Respuesta a Droga , Inhibidores de Histona Desacetilasas/síntesis química , Inhibidores de Histona Desacetilasas/química , Simulación del Acoplamiento Molecular , Estructura Molecular , Proteínas Recombinantes/biosíntesis , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/química , Relación Estructura-Actividad , Nicotiana/metabolismo
9.
Bioorg Chem ; 92: 103200, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31470199

RESUMEN

In processes regulated by quorum sensing (QS) bacteria respond to the concentration of autoinducers in the environment to engage in group behaviours. Autoinducer-2 (AI-2) is unique as it can foster interspecies communication. Currently, two AI-2 receptors are known, LuxP and LsrB, but bacteria lacking these receptors can also respond to AI-2. In this work, we present an efficient and reproducible synthesis of a novel chemical probe, d-desthiobiotin-AI-2. This probe binds both LuxP and LsrB receptors from different species of bacteria. Thus, this probe is able to bind receptors that recognise the two known biologically active forms of AI-2, presenting the plasticity essential for the identification of novel unknown AI-2 receptors. Moreover, a protocol to pull down receptors bound to d-desthiobiotin-AI-2 with anti-biotin antibodies has also been established. Altogether, this work highlights the potential of conjugating chemical signals to biotinylated derivatives to identify and tag signal receptors involved in quorum sensing or other chemical signalling processes.


Asunto(s)
Biotina/análogos & derivados , Proteínas de Escherichia coli/metabolismo , Homoserina/análogos & derivados , Lactonas/síntesis química , Percepción de Quorum/efectos de los fármacos , Alquinos/química , Biotina/síntesis química , Biotina/química , Biotina/metabolismo , Proteínas Portadoras/metabolismo , Escherichia coli/genética , Homoserina/síntesis química , Homoserina/metabolismo , Lactonas/metabolismo , Ligandos , Estructura Molecular , Transducción de Señal
10.
Bioorg Chem ; 85: 75-81, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30602129

RESUMEN

Quorum sensing (QS) regulates population-dependent bacterial behaviours, such as toxin production, biofilm formation and virulence. Autoinducer-2 (AI-2) is to date the only signalling molecule known to foster inter-species bacterial communication across distantly related bacterial species. In this work, the synthesis of pure enantiomers of C4-propoxy-HPD and C4-ethoxy-HPD, known AI-2 analogues, has been developed. The optimised synthesis is efficient, reproducible and short. The (4S) enantiomer of C4-propoxy-HPD was the most active compound being approximately twice as efficient as (4S)-DPD and ten-times more potent than the (4R) enantiomer. Additionally, the specificity of this analogue to bacteria with LuxP receptors makes it a good candidate for clinical applications, because it is not susceptible to scavenging by LsrB-containing bacteria that degrade the natural AI-2. All in all, this study provides a new brief and effective synthesis of isomerically pure analogues for QS modulation that include the most active AI-2 agonist described so far.


Asunto(s)
Antibacterianos/farmacología , Pentanonas/farmacología , Percepción de Quorum/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Portadoras/metabolismo , Escherichia coli/fisiología , Proteínas de Escherichia coli/metabolismo , Pentanonas/síntesis química , Pentanonas/metabolismo , Estereoisomerismo , Vibrio/fisiología
11.
Clin Mol Allergy ; 17: 2, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30804711

RESUMEN

BACKGROUND: A growing use of complementary alternative medicine (CAM) has been found in Europe as well in Italy for chronic diseases, including the allergic rhinitis. The study aims at investigating the prevalence and the pattern of use of CAM amongst patient with allergic rhinitis. METHODS: A 12-item questionnaire was developed by a panel of experts and administered to patients with moderate/severe allergic rhinitis consecutively referring during the study time-frame to seven allergy clinics placed all around Italy. The items covered several topics including reason for choosing CAM, its clinical efficacy, schedule of treatment, costs, type of therapy. RESULTS: Overall 359 questionnaires were analysed. 20% of patients declared CAM use. A significant correlation between the use of CAM and female sex (p < 0.01) and with a higher level of education (p < 0.01) was observed. CAM users were adults (36% in the range between 20 and 40 years and 32% between 41 and 60 years). Youngsters (< 20 years) (7%) and elderly (> 60) (25%) less frequently used CAM.The most used type of CAM was homoeopathy (77% of patients). 60% of users would recommend CAM despite a poor clinical efficacy according to 67% of them. CONCLUSIONS: Although no evidence supports CAM efficacy and safety, the number of patients who relies on it is not negligible. As allergic rhinitis is not a trivial disease, the use of CAM as the only treatment for it should be discouraged at any level, but by general practitioner and specialist in particular.

12.
Bull Entomol Res ; 109(4): 419-425, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29734954

RESUMEN

Strawberry is affected by several pests and diseases. Neopamera bilobata is an emerging pest that has been reported by several strawberry growers, usually associated with catfacing symptoms in fruits. We evaluated intercropping garlic or Chinese chives on N. bilobata populations on strawberry crops grown in high tunnels in two experiments. In the first experiment, we evaluated N. bilobata populations on strawberry intercropping with garlic plants (three densities: 8, 16, 24 GP - garlic plant per plot) on the bags by taking 12 samples from December 2015 to April 2017. N. bilobata populations on strawberry were also assessed when Chinese chives were grown under the suspended wooden structures in which strawberry plants are grown ('undercropping') (14 samples), in two high tunnels, from November 2016 to March 2017. The number of nymphs and adults on 14 randomly selected fruits per plot were assessed. During the garlic intercropping experiment, the treatments of three densities of garlic reduced N. bilobata populations; however, the 24 GP treatment caused a greater reduction than the 8 GP treatment. Garlic densities reduced N. bilobata populations by 35, 50, and 64% for the 8, 16, and 24 GP treatments, respectively. Chinese chives cultivated under the structures reduced N. bilobata populations by 47%. The results suggest that intercropping garlic or undercropping Chinese chives are suitable tools to be tested in integrated pest management in strawberry crops.


Asunto(s)
Cebollino/crecimiento & desarrollo , Cadena Alimentaria , Fragaria , Ajo/crecimiento & desarrollo , Heterópteros/fisiología , Animales , Brasil , Producción de Cultivos/métodos , Fragaria/crecimiento & desarrollo , Herbivoria , Dinámica Poblacional
13.
Trop Anim Health Prod ; 51(2): 465-468, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30083862

RESUMEN

Bituminaria bituminosa (C.H. Stirt.) is a drought tolerant legume that grows spontaneously in subtropical areas: Canary Islands (Spain) and in North African and Mediterranean regions, traditionally used as forage for ruminants. The aim of this research was to investigate the potential of B. bituminosa as a high protein resource for poultry feed by means of feed intake, growth, feed conversion rate (FCR), protein efficiency ratio (PER), and the influence of B. bituminosa feed form (fresh green and dried) on the preference by chicks. B. bituminosa showed higher crude protein content (CP), neutral detergent fiber (NDF), and gross energy than commercial feed. Average daily feed intake (ADFI) for the commercial feed group (control group) was higher than ADFI of the B. bituminosa group (experimental group). However, both groups had no significant differences in total crude protein intake, total NDF intake, average daily gain (ADG), FCR, and PER. The poultry's preference for fresh green B. bituminosa was higher than for dry B. bituminosa. Our results suggest that B. bituminosa (tedera) could be an alternative feedstuff in tropical countries or where protein sources are scarce and costly.


Asunto(s)
Fabaceae/química , Aves de Corral/crecimiento & desarrollo , Alimentación Animal/análisis , Animales , Pollos/metabolismo , Fibras de la Dieta/análisis , Proteínas en la Dieta/análisis , Fabaceae/metabolismo , Aves de Corral/metabolismo , España
14.
Trop Anim Health Prod ; 51(6): 1757-1761, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30730026

RESUMEN

The objective of this study was to contribute to the characterization of nutritional potentials, with special attention to the total phenol and condensed tannins content and the effects on in vitro digestibility of some browsing shrub legumes traditionally used for ruminant feeding. The varieties selected were Bituminaria bituminosa var. bituminosa (BBB), Bituminaria bituminosa var. albormaginata (BBA), Chamaecytisus proliferus var. palmensis (CPP), Chamaecytisus proliferus var. canariae (CPC), and Adenocarpus foliosus (AF). Chemical composition, in vitro digestibility, and net energy for lactation (NE) were analyzed and compared among varieties; the effects of total phenol (TP) and condensed tannins (CT) compounds on digestibility were estimated. Condensed tannins ranged from 1 to 5 g/kg DM of tannins, while total phenols ranged from 9 to 32 g/kg DM of tannins. In vitro organic matter digestibility (OMD) ranged from 0.52 to 0.71, and estimated net energy for lactation (NE) ranged from 4.2 to 5.8 MJ/kg DM, with significant differences among all the varieties. This Chamaecytisus varieties (CPC, CPP) have higher feeding values, following CPC > CPP > AF > BBB > BBA in order. Although there were condensed tannins and total phenols in all the shrubs analyzed, total phenol contents differed significantly between the shrubs. The effect of the content of the total phenols and of the tannins condensed in the OMD of the varieties of shrubs analyzed, shows that the higher amounts of total phenols in some of the varieties of shrubs analyzed, increased the in vitro digestibility (OMD) of the shrubs but high amounts of CT decreased OMD.


Asunto(s)
Fabaceae/química , Valor Nutritivo , Fenoles/química , Fenoles/metabolismo , Taninos/química , Taninos/metabolismo , Alimentación Animal/análisis , Animales
15.
Allergy ; 73(8): 1622-1631, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29569295

RESUMEN

BACKGROUND: Multimorbidity in allergic airway diseases is well known, but no data exist about the daily dynamics of symptoms and their impact on work. To better understand this, we aimed to assess the presence and control of daily allergic multimorbidity (asthma, conjunctivitis, rhinitis) and its impact on work productivity using a mobile technology, the Allergy Diary. METHODS: We undertook a 1-year prospective observational study in which 4 210 users and 32 585 days were monitored in 19 countries. Five visual analogue scales (VAS) assessed the daily burden of the disease (i.e., global evaluation, nose, eyes, asthma and work). Visual analogue scale levels <20/100 were categorized as "Low" burden and VAS levels ≥50/100 as "High" burden. RESULTS: Visual analogue scales global measured levels assessing the global control of the allergic disease were significantly associated with allergic multimorbidity. Eight hypothesis-driven patterns were defined based on "Low" and "High" VAS levels. There were <0.2% days of Rhinitis Low and Asthma High or Conjunctivitis High patterns. There were 5.9% days with a Rhinitis High-Asthma Low pattern. There were 1.7% days with a Rhinitis High-Asthma High-Conjunctivitis Low pattern. A novel Rhinitis High-Asthma High-Conjunctivitis High pattern was identified in 2.9% days and had the greatest impact on uncontrolled VAS global measured and impaired work productivity. Work productivity was significantly correlated with VAS global measured levels. CONCLUSIONS: In a novel approach examining daily symptoms with mobile technology, we found considerable intra-individual variability of allergic multimorbidity including a previously unrecognized extreme pattern of uncontrolled multimorbidity.


Asunto(s)
Hipersensibilidad/epidemiología , Aplicaciones Móviles , Multimorbilidad , Rinitis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación del Resultado de la Atención al Paciente , Prevalencia , Estudios Prospectivos , Proyectos de Investigación , Adulto Joven
16.
Allergy ; 73(2): 505-510, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28906011

RESUMEN

Mobile technology has been used to appraise allergic rhinitis control, but more data are needed. To better assess the importance of mobile technologies in rhinitis control, the ARIA (Allergic Rhinitis and its Impact on Asthma) score ranging from 0 to 4 of the Allergy Diary was compared with EQ-5D (EuroQuol) and WPAI-AS (Work Productivity and Activity Impairment in allergy) in 1288 users in 18 countries. This study showed that quality-of-life data (EQ-5D visual analogue scale and WPA-IS Question 9) are similar in users without rhinitis and in those with mild rhinitis (scores 0-2). Users with a score of 3 or 4 had a significant impairment in quality-of-life questionnaires.


Asunto(s)
Asma/complicaciones , Aplicaciones Móviles , Calidad de Vida , Rinitis Alérgica/complicaciones , Encuestas y Cuestionarios , Adulto , Estudios Transversales , Europa (Continente) , Femenino , Humanos , Masculino , Proyectos Piloto , Rendimiento Laboral
17.
Org Biomol Chem ; 16(38): 6860-6864, 2018 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-30226251

RESUMEN

The plant hormone conjugate 2-O-(indole-3-acetyl)-myo-inositol (IAInos) has been selectively prepared for the first time by two routes from myo-inositol. One of the syntheses depended upon the construction of the 3-indoleacetyl group by a Fischer indole synthesis on an unreactive axial hydroxyl group, while the other via a direct acylation of the equatorially orientated hydroxy group created by conformational constraint of the cyclohexane ring. The latter synthesis produced IAInos in 5 steps and 29% overall yield.


Asunto(s)
Ácidos Indolacéticos/síntesis química , Indoles/síntesis química , Inositol/síntesis química , Reguladores del Crecimiento de las Plantas/síntesis química , Acilación , Técnicas de Química Sintética , Ácidos Indolacéticos/química , Indoles/química , Inositol/análogos & derivados , Reguladores del Crecimiento de las Plantas/química
18.
Phys Chem Chem Phys ; 20(9): 6354-6364, 2018 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-29435521

RESUMEN

The confinement effects of a zeolite framework on the adsorption of a bidentate 4,4'-bipyridine (44BPY) ligand on the straight channel of H-ZSM-5 have been investigated by density functional theory calculations using B3LYP, B3LYP-D3, M06-2X, M06-2X-D3 functionals, and the MP2 method with two basis sets 6-31+G* and 6-31++G(2d,2p). The straight channel is simulated by a realistic cluster model of 32 tetrahedra (T), having two aluminum atoms located in the straight and intersection regions, respectively. The potential energy surface of the double proton transfer reaction from the Brønsted acid sites of H-ZSM-5 to 44BPY is characterized by three minima corresponding to two monodentate ion pair complexes 44BPYH+/32T- and one bidentate ion pair complex 44BPYH22+/32T2- formed consecutively via two distinct pathways. No energy minimum is found for a neutral hydrogen bonding structure. The relative stabilities of these 44BPY adsorption complexes and the transition states connecting them do not exceed 4.9 and 4.2 kcal mol-1, respectively. Consequently equilibrium between the mono and bidentate complexes could be established. Our results clearly show that the adsorption energy for all complexes is substantially governed by the confinement effects executed through steric constraints and dispersive van der Waals interactions. The calculated vibrational frequencies and frequency shifts of 44BPY adsorbed as mono or diprotonated species are in good agreement with our Raman spectra of 44BPY occluded in H-ZSM-5 of different Si/Al ratios.

19.
Trop Anim Health Prod ; 50(8): 1941-1945, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29777365

RESUMEN

The objective of this study was to evaluate the effects of replacing rye-grass (Lolium spp.) hay with banana (Musa acuminata L.) by-products on feed intake, average daily gain (ADG), and feed conversion rate (FCR) in Pelibuey (hair sheep breed) lambs. The lambs (n = 22; initial BW = 14.8 ± 2.5 kg) were individually housed and fed on two different types of diet for 58 days: the first group (experimental diet) received as forage a mixture of fresh banana by-products composed of leaves and pseudostem. The second group received commercial rye-grass hay (conventional diet) as a fiber source. Both groups received a supplementary commercial concentrate food. The total daily forage intake and FCR were lower (P < 0.001) in animals fed on the conventional diet (rye-grass hay) than animals fed on the experimental diet (banana by-products). However, there were no significant differences in total dry matter intake, total digestible energy intake, total body weight gain, and ADG between the two groups. The results obtained in this study suggest that banana by-products could be used as alternative forage for Pelibuey lambs raised in subtropical conditions.


Asunto(s)
Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Dieta/veterinaria , Lolium , Musa , Animales , Peso Corporal , Ingestión de Energía , Secale , Ovinos , Oveja Doméstica , Aumento de Peso
20.
Arch Ital Biol ; 156(1-2): 64-86, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30039837

RESUMEN

Some food/food components have been the object of request of authorization to the use of health claims related to cognitive function in adults and compliant with the Regulation (EC) 1924/2006. Most of the requests have received a negative opinion by the European Food Safety Authority (EFSA) also because of the choice of not appropriate outcome variables (OVs) and methods of measurement (MMs) selected in the trials used to substantiate the claim. This manuscript referes to the collection, collation and critical analysis of OVs and MMs related to cognitive function in adults. OVs and MMs were collected from the EFSA Guidance document and the applications for authorization of health claims pursuant to the Articles 13(5). The critical analysis of OVs and MMs, performed by a literature review, was aimed at defining their appropriateness in the context of a specific claimed effect. The results highlight the importance of an adequate choice of OVs and MMs for an effective substantiation of the claims related to cognitive functioning. The information provided in this document may serve to EFSA for updating the guidance on the scientific requirements for health claims related to cognitive functions, but also for a better design of randomized controlled trials aimed at substantiating such health claims.


Asunto(s)
Cognición , Dieta , Alimentos , Inocuidad de los Alimentos , Humanos , Legislación de Medicamentos , Pruebas Neuropsicológicas
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