Gold Nucleation Inhibition by Halide Ions: a Basis for a Seed-Mediated Approach

In the present work, we examine the effect of halide ions on gold nucleation, a typical synthetic variable in the wet-chemical production of gold nanostructures. It was found that the homogeneous nucleation of gold by the chemical reduction of aqueous gold ions is kinetically quenched by an increase in the concentration of halide ions, and this effect grows stronger as the Au–halide complex stability increases. The nucleation quenching is not exclusively related to a specific reducing agent, but appears to be a more general behavior, and is affected by the pH of the media. While no nucleation is observed, Au(I) metastable species coexist together with the reducer, constituting metastable solutions. It is demonstrated that nucleation inhibition by halide ions can be employed as a basis for a seed-mediated approach to produce gold nanostructures. The metastable solutions are proved to function as growth baths, where Au(I) reduction is triggered on the surface of previously synthesized gold nanoparticles, driving their growth in the absence of secondary nucleation. It is also shown how, with this approach, the synthesis conditions can be rationally designed to obtain gold nanoparticles with the desired properties in a controlled and reproducible fashion.Fil: Moiraghi, Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Douglas Gallardo, Oscar Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Coronado, Eduardo A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Macagno, Vicente Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Perez, Manuel Alejo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentin

A comparative study of physicochemical tests for quality prediction of Argentine wheat flours used as corrector flours and for cookie production

Several physicochemical tests are employed in quality evaluation of wheat. Most of the exported Argentinean wheat flour is used as corrector flour in breadmaking. A small percentage is actually used in cookie production. No study has determined which predictive tests are most suitable for the quality prediction of bread (using flour as corrector) and cookies made from Argentinean wheat. The objectives of this study were to compare the suitability of predictive tests in the assessment of wheat flour attributes in the production of bread and cookies and to establish the relationship between the tests and flour components. Several expected associations were found between the SRC test and the composition parameters. Moreover, various flour components influencing the SDS sedimentation index (SDS-SI), the Zeleny index and the alkaline water retention capacity (AWRC) were established. The cookie factor (CF) was negatively correlated with sucrose, carbonate and water SRC and with AWRC. In addition, the bread loaf specific volume (LV) was correlated with the SDS-SI, the Zeleny index and the lactic acid SRC. In conclusion, several components of Argentine wheat affecting predictive tests were found. The SRC test allowed straight assessment of the bread and cookie quality of Argentinean wheat.Fil: Colombo, Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Cátedra de Química Biológica; ArgentinaFil: Pérez, G.T.. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Cátedra de Química Biológica; ArgentinaFil: Ribotta, Pablo Daniel. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Cátedra de Química Biológica; Argentina. Provincia de Córdoba. Ministerio de Ciencia y Técnica. Centro de Excelencia en Productos y Procesos de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: León, A.E.. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Cátedra de Química Biológica; Argentina. Provincia de Córdoba. Ministerio de Ciencia y Técnica. Centro de Excelencia en Productos y Procesos de Córdoba; Argentin

Effect of Different Wheat Sprouting Conditions on the Characteristics of Whole-Wheat Flour

Fil: Navarro, José Luis. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Navarro, José Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Fil: Losano Richard, Pedro. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Losano Richard, Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Fil: Moiraghi, Malena. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Moiraghi, Malena. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Fil: Bustos, Mariela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Fil: Bustos, Mariela. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: León, Alberto Edel. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: León, Alberto Edel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Fil: Steffolani, María Eugenia. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Steffolani, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Research background. Controlled sprouting promotes physiological and biochemical changes in whole grains, improves their nutritional value and offers technological advantages for breadmaking as an alternative to traditional whole grains. The aim of this study is to find sprouting conditions for the grains of Klein Valor wheat variety (Triticum aestivum L.) that would increase the nutritional value without significantly affecting the gluten proteins, which are essential in wholegrain baked goods. Experimental approach. The chemical and nutritional composition, enzymatic activity and pasting properties of the suspensions of unsprouted and sprouted whole-wheat flour were evaluated. Results and conclusions. This bioprocess allowed us to obtain sprouted whole-wheat flour with different degrees of modification in its chemical composition. Sprouting at 25 °C resulted in an observable increase in enzymatic activity and metabolic processes, particularly α-amylases, which significantly affect the starch matrix and the associated pasting properties. Additionally, there was a smaller but still notable effect on the structure of the cell walls and the protein matrix due to the activation of endoxylanases and proteases. In contrast, sprouting at 15 and 20 °C for 24 h allowed for better process control as it resulted in nutritional improvements such as a higher content of free amino acid groups, free phenolic compounds and antioxidant capacity, as well as a lower content of phytates. In addition, it provided techno-functional advantages due to the moderate activation of α-amylase and xylanase. A moderate decrease in peak viscosity of sprouted whole-wheat flour suspensions was observed compared to the control flour, while protein degradation was not significantly prolonged. Novelty and scientific contribution. Sprouted whole-wheat flour obtained under milder sprouting conditions with moderate enzymatic activity could be a promising and interesting ingredient for wholegrain baked goods with improved nutritional values and techno-functional properties. This approach could avoid the use of conventional flour improvers and thus have a positive impact on consumer acceptance and enable the labelling of the product with a clean label.info:eu-repo/semantics/publishedVersionFil: Navarro, José Luis. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Navarro, José Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Fil: Losano Richard, Pedro. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Losano Richard, Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Fil: Moiraghi, Malena. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Moiraghi, Malena. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Fil: Bustos, Mariela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Fil: Bustos, Mariela. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: León, Alberto Edel. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: León, Alberto Edel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina.Fil: Steffolani, María Eugenia. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Steffolani, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencia y Tecnología de Alimentos; Argentina

Human colonic in vitro fermentation of water-soluble arabinoxylans from hard and soft wheat alters Bifidobacterium abundance and short-chain fatty acids concentration

The human intestinal microbiome plays an important role in health due to the large number of beneficial effects related to the bacterial profile and the metabolites generated in the intestine. Arabinoxylans are compounds present in different cereals such as wheat and they can modulate the profile and functioning of some beneficial bacteria from human intestinal microbiota. In the present work, a colonic in vitro fermentation with human faecal inoculum was done using arabinoxylans extracted from Argentinian hard and soft wheat as substrates. Molecular size alteration of arabinoxylans were studied during fermentation and Lactobacillus and Bifidobacterium abundance as well as short chain fatty acids concentrations were determined. The arabinoxylans fermentation was proved to induce the growth of Bifidobacterium and the release of short-chain fatty acids. The speed and efficiency of fermentation were different for each of the arabinoxylan extracted from both wheat genotypes, perhaps because of differences in their chemical and physical structures. The consumption of water-extractable arabinoxylans (WE-AX) (either supplemented or enriched) to maintain the balance or modulate in a favorable way the profile of Bifidobacterium can be an important contribution to the human health.Fil: Paesani, Candela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Sciarini, Lorena Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Moiraghi, Malena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Salvucci, Emiliano Jesus. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Prado, Samira B. R.. Universidade de Sao Paulo; BrasilFil: Perez, Gabriela Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Fabi, João Paulo. Universidade de Sao Paulo; Brasi

Arabinoxylan from Argentinian whole wheat flour promote the growth of Lactobacillus reuteri and Bifidobacterium breve

Arabinoxylans are part of dietary fibre and have received attention given their emergent prebiotic character. Four arabinoxylans extracts were obtained from Argentinian soft and hard wheat. In vitro assays were performed to describe the extent to which the extracts from whole wheat flour support selective growth of Bifidobacterium breve and probiotic Lactobacillus reuteri ATCC23272 in a defined media. The prebiotic effect was evaluated by three quantitative scores: relative growth, prebiotic activity score and prebiotic index. For prebiotic index equation the growth of Bacteroides and Clostridium strains was compared to that of bifidobacteria and lactic acid bacteria. All the arabinoxylans extracts supported the growth of Lactobacillus and Bifidobacterium, reaching higher prebiotic activity score values than inulin (0·37 and 0·36 for Lactobacillus and Bifidobacterium respectively). AX2 from soft wheat and AX4 from hard showed similar prebiotic index value to commercial inulin (2·64, 2·52 and 2·22 respectively), and AX3 extract presented higher prebiotic index value (4·09) than the positive control and other prebiotic index reported for arabinoxylans. These extracts could be used as prebiotic, synbiotic compositions or novel food prototypes to treat dysbiosis associated with many diseases. Significance and Impact of the Study: The present work demonstrates that AX extracts from Argentinian soft and hard wheat promote efficiently the growth of probiotic strain L. reuteri ATCC23272 and B. breve 286, validated with three different parameters that consider the growth of representative strains of Bacteria genera found in the gut. The evaluation of AX extracts as a food supplement in a murine model could confirm their ability to modulate the microbiome. Novel food prototypes including AX and probiotics could relieve local symptoms and may act as psychobiotics with a beneficial effect on microbiome-brain axis.Fil: Paesani, Candela. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Salvucci, Emiliano Jesus. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Moiraghi, Malena. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Fernandez Canigia, Liliana Beatriz. Hospital Aleman; ArgentinaFil: Perez, Gabriela Teresa. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentin

Effect of wheat pearling process on composition and nutritional profile of flour and its bread-making performance

Pearling process on wheat grains was evaluated as a strategy to reduce their adverse effect on whole-wheat bread (WWB) quality and simultaneously preserve part of the nutrients of the whole grain. The grains were pearled applying different times (25, 125, 225 and 250 s) before milling. Characteristic, nutritional composition and rheology of the pearled wheat flour (P), and their bread-making performance, were analysed. Whole-wheat flour and refined flour (RF) were used as control. P125s, P225s and P250s exhibited a superior nutritional profile concerning RF. P had lower water absorption and led to higher volume bread with lighter crust and crumb compared to WWB. P125s, P225s and P250s bread showed characteristics similar to those of white bread, but their hardness was lower. The improvement resulted from the extraction of the outermost bran layers, a decrease in insoluble dietary fibre, an increase in the proportion of water-soluble pentosans and a lower protein weakening.Fil: Navarro, José Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Biglione, Camila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Paesani, Candela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Moiraghi, Malena. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Cátedra de Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Leon, Alberto Edel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Cátedra de Química Biológica; ArgentinaFil: Steffolani, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Cátedra de Química Biológica; Argentin

An assessment of the effect of hepatitis B vaccine in decreasing the amount of hepatitis B disease in Italy

Abstract Background Hepatitis B (HBV) infection is an important cause of morbidity and mortality and it is associated to a higher risk of chronic evolution in infected children. In Italy the anti-HBV vaccination was introduced in 1991 for newborn and twelve years old children. Our study aims to evaluate time trends of HBV incidence rates in order to provide an assessment of compulsory vaccination health impact. Method Data concerning HBV incidence rates coming from Acute Viral Hepatitis Integrated Epidemiological System (SEIEVA) were collected from 1985 to 2006. SEIEVA is the Italian surveillance national system that registers acute hepatitis cases. Time trends were analysed by joinpoint regression using Joinpoint Regression Program 3.3.1 according to Kim's method. A joinpoint represents the time point when a significant trend change is detected. Time changes are expressed in terms of the Expected Annual Percent Change (EAPC) with 95% confidence interval (95% CI). Results The joinpoint analysis showed statistically significant decreasing trends in all age groups. For the age group 0–14 EAPC was -39.0 (95% CI: -59.3; -8.4), in the period up to 1987, and -12.6 (95% CI: -16.0; -9.2) thereafter. EAPCs were -17.9 (95% CI: -18.7; -17.1) and -6.7 (95% CI: -8.0; -5.4) for 15–24 and ≥25 age groups, respectively. Nevertheless no joinpoints were found for age groups 15–24 and ≥25, whereas a joinpoint at year 1987, before compulsory vaccination, was highlighted in 0–14 age group. No joinpoint was observed after 1991. Discussion Our results suggest that the introduction of compulsory vaccination could have contribute partly in decreasing HBV incidence rates. Compulsory vaccination health impact should be better investigated in future studies to evaluate the need for changes in current vaccination strategy.</p