168 research outputs found
Functional Analysis of Lactic Acid Bacteria and Bifidobacteria and Their Effects on Human Health
Many lactic acid bacteria (LAB) and Bifidobacteria are beneficial components of human, animal, foods, and beverage microbiota [...]This research was funded by the Spanish Ministry of Science, Innovation and Universities, grant number RTI2018-097114-B-I00
Supramolecular Structure and Renaturation of a (1→3)-β-D-Glucan Compared with Curdlan and Scleroglucan
A (1→3)-β-D-Glucan produced by Lactobacillus suebicus CUPV221 strain was
investigated by tapping mode atomic force microscopy (TM-AFM), to compare its
supramolecular structure and conformation with two commercial polysaccharides: curdlan
and scleroglucan. It was found that the β-D-Glucan was a (1→3)(1→2)-β-D-Glucan and at
room temperature formed three-dimensional networks by entanglements between strands, as
does scleroglucan. However, (1→3)(1→2)-β-D-Glucan strands seemed to be more stiff than
those of scleroglucan. It was also observed that curdlan samples deposited from 5 mM NaOH
aqueous solution showed supermolecular assemblies, recognized in the literature as micelles,
which are controlled by hydrophobic hydration. The (1→3)(1→2)-β-D-Glucan in alkaline
aqueous solutions produced different supramolecular structures depending on pH, and at
0.4 M NaOH (pH 13.16), denaturation took place. After neutralizing the alkaline solution
with HCl, the formation of short linear, circular, and hairpin structures was observed.This study was supported by grants AGL2009-12998-C03 and AGL2012-40084 from the Spanish
Ministry of Science and Innovation, and IT335-10 from the Basque Government. Ana Isabel Puertas
acknowledges the “Gobierno Vasco, Dpto. Agricultura, Pesca y Alimentación” for the fellowship
Solastalgia y conductas pro-ambientales en un conflicto socioambiental por la construcción de una hidroeléctrica
Introducción: La construcción de megaproyectos hídricos implica una reconfiguración
territorial donde se ven afectadas las fuentes de agua dulce, la biodiversidad terrestre y
acuática, y los asentamientos humanos que colindan con dichas construcciones. Objetivo:
estimar la asociación entre las conductas proambientales con la solastalgia entre las personas
que se encuentran ejerciendo un proceso de resistencia social contra la Central Hidrosogamoso
en el departamento de Santander, Colombia. Metodología: se utilizó un diseño de estudio
transversal en el que se entrevistaron integrantes y no integrantes de grupos ambientalistas de
las zonas de influencia del proyecto. Se realizó un análisis descriptivo de las variables
sociodemográficas de los dos grupos de comparación presentando frecuencias absolutas y
relativas y diferencias significativas por medio de la prueba ji cuadrado, exacta de Fisher y U
de Mann Whitney. Se utilizó un modelo de regresión lineal múltiple en el que la variable
dependiente fue el puntaje de solastalgia y las variables independientes fueron las escalas de
las conductas proambientales: altruismo, austeridad, equidad, conducta ecológica, deliberación,
indignación y aprecio por lo natural, además, se ajustó por algunas variables
sociodemográficas de interés. Resultados: los grupos comparados presentaron diferencias
importantes en cuanto a la zona de procedencia, condiciones económicas y organización social.
El incremento de 5 puntos en la escala del sentimiento de indignación incrementó 0.98 la
escala de solastalgia (IC95%: 0.19; 1.78). Las personas sin pareja estable tuvieron 3.02 puntos
menos de solastalgia comparadas con personas casadas o en unión libre (IC95%: -4.96; -1.44),
mientras que aquellas con alto nivel educativo obtuvieron 2.02 puntos menos que las personas
con primaria y bachillerato (IC95%: -3.99; -0.06). Un modelo alterno mostró que no pertenecer
a un grupo ambientalista disminuye en 2.29 puntos la solastalgia, comparado con pertenecer a
un grupo (IC95%: -4.31; -0.28),. Conclusión: posiblemente las motivaciones por las cuales los
actores involucrados se resisten a las transformaciones territoriales ocasionadas por la
construcción de las represas son más un reflejo de la condición socioeconómica que de la preocupación de los actores por el daño del medio ambiente y además, esta resistencia es un
fenómeno que se limita a aquellos que están afectados directamente en el área de influencia del
proyectoIntroduction: The construction of water megaprojects implies a territorial reconfiguration
where the sources of fresh water, the terrestrial and aquatic biodiversity, and the human
settlements that adjoin these constructions are affected. Objective: to estimate the association
between pro-environmental behavior and solastalgia among people who are exercising a
process of social resistance against the Hidrosogamoso Power Plant in the department of
Santander, Colombia. Methodology: a cross-sectional study was used in which participants and
non-members of environmental groups from the project's areas of influence were interviewed.
A descriptive analysis of the sociodemographic variables of the two comparison groups was
performed, presenting absolute and relative frequencies and significant differences by means of
the Ji square test, Fisher exact test and Mann Whitney U test. A multiple linear regression
model was used in which the dependent variable was the solastalgia score and the independent
variables were the scales of the pro-environmental behaviors: altruism, austerity, equity,
ecological behavior, deliberation, indignation and appreciation for the natural, in addition , it
was adjusted by some sociodemographic variables of interest. Results: the compared groups
showed significant differences in the area of origin, economic conditions and social
organization. The increase of 5 points in the scale of the feeling of indignation increased 0.98
the scale of solastalgia (IC95%: 0.19; 1.78). People with no stable partners had 3.02 points less
solasthalgia compared to married or free union (95% CI: -4.96; -1.44), while those with a high
educational level obtained 2.02 points less than people with primary and high school education
(IC95 %: -3.99; -0.06). An alternate model showed that not belonging to an environmental
group decreases solasalgia by 2.29 points, compared to belonging to a group (95% CI: -4.31; -
0.28). Conclusion: possibly the motivations by which the actors involved resist the territorial
transformations caused by the construction of the dams are more a reflection of the
socioeconomic condition than of the concern of the actors for the damage of the environment
and also, this resistance is a phenomenon that is limited to those who are directly affected in
the area of influence of the project
Causas, intereses y desarrollo histórico de la acción colectiva empresarial en el ámbito agrario: el caso del cooperativismo en el sector oleícola
The objective of this paper is explore the roots of the co-operative movement in the food oil sector from a historical perspective through a bibliographical review of the diverse studies carried out at the regional and provincial levels in Spain. It explores the causes of co-operatives’ creation and the profile of the farmers who benefited from the experience. It ascertains the level of business development in the organisational, human and technological spheres, analysing the conditioning factors limiting co-operative action to the stockpiling and production areas, with little penetration in cooperation at the second level of bottling and refining. An empirical study is made of evolution in one of the Spanish provinces where the incidence of this type of co-operative is significant.Agrarian co-operatives, food oil sector, business development, agrarian history, organisational ecology, government of the enterprise.
Determination of phenolic composition in ancestral grains for food use. Comparison of analytical methods and antioxidant activity
The aim of this study was to quantify the total phenolic compounds of different ancestral grains such as two varieties of tef (Eragrostis tef) white and brown, buchwheat (Fagopyrum esculentum) and spelta (Triticum spelta), using different spectrophotometric methods (Folin-Ciocalteu and Fast Blue BB) and to compare with the obtained results using high performance liquid chromatography coupled to diode array detector and mass spectrometry (HPLC-DAD-MS). Furthermore, antioxidant activity of the extracts from these samples has been compared using two different in vitro assays: ferric reducing power (FRAP) and the ability to scavenge the ABTS•+. The use of HPLC-DAD-MS allowed us to detect different groups of phenolic compounds: hydroxybenzoic and hydroxycinnamic derivatives, flavonols, flavones and flavanols. Flavones derivatives were the most abundant in spelta, white and brown teff. However, buckwheat presented the highest in flavanols (64 %). The phenolic compounds quantification carried out by HPLC-DAD-MS could be more appropriate than the obtained results using spectrophotometric methods. Regarding the antioxidant activity, the buckwheat seeds showed the highest value, which could be related to the highest phenolic content.El objetivo de este estudio fue cuantificar los compuestos fenólicos totales de diferentes granos ancestrales: dos variedades de tef (Eragrostis tef), trigo sarraceno (Fagopyrum esculentum) y trigo espelta (Triticum spelta) por diferentes métodos espectrofotométricos (Folin-Ciocalteu y Fast Blue BB) y comparar con los resultados obtenidos de estudiar la composición fenólica individualizada mediante cromatografía líquida de alta resolución acoplada a un sistema de detección de fotodiodos y espectrometría de masas (HPLC-DAD-MS). También se determinó la actividad antioxidante in vitro de los extractos de los granos ancestrales estudiados por el método TEAC (capacidad antioxidante equivalente de Trolox) y FRAP (poder antioxidante reductor del hierro). El uso de HPLC-DAD-MS permitió identificar un gran número de compuestos fenólicos: compuestos hidroxibenzoicos, hidroxicinámicos, flavonoles, flavonas y flavanoles. Las flavonas fueron la familia de compuestos fenólicos más abundante detectada en las muestras de espelta, teff, blanco y marrón. Sin embargo, en el trigo sarraceno son los flavanoles (64 %). La cuantificación de los compuestos fenólicos por HPLC-DAD-MS parece más oportuna que por los métodos espectrofotométricos. Con respecto a la actividad antioxidante, el trigo sarraceno mostró los valores más altos frente a su capacidad de captar radicales libres y poder reductor en relación a las otras muestras estudiadas, pudiéndose relacionar con su alto contenido en compuestos fenólicos
Anthocyanin composition in fig (Ficus carica L.)
[EN] The anthocyanin composition was analysed in fig fruit (Ficus carica L.) from five different varieties (Colar, Cuello de Dama (green),
Cuello de Dama (dark purple), Granilla and Bursa Siyahi). Fifteen anthocyanin pigments were detected, most of them containing
cyanidin (Cy) as aglycone; some pelargonidin (Pg) derivatives were also found. Rutinose and glucose were present as substituting
sugars, as well as acylation with malonic acid. Minor levels of peonidin 3-rutinose (Pn 3-rutinoside) in the pulp were also detected.
Other noticeable aspects in the pigment composition of the fig were the detection of anthocyanidin-derived pigments, namely
5-carboxypyranocyanidin-3-rutinoside, a cyanidin 3-rutinose dimer and five condensed pigments containing C–C linked anthocyanins
(Cy and Pg) and flavanol (catechin and epicatechin) residues. Total anthocyanin content in the skin ranged between 32 and 97 mgg 1 and
between 1.5 and 15 mgg 1 in the pulp. The main anthocyanin in both parts of the fruit was Cy 3-rutinoside (48–81% in skin and 68–79%
in pulp) usually followed by Cy 3-glucoside (5–18% in skin and 10–15% in pulp). Malonyl derivatives were more abundant in the skin
(1.2–6.5%) than in the pulp (1.0–2.6%)
Exopolysaccharide-producing Lacticaseibacillus paracasei strains isolated from kefir as starter for functional dairy products
Exopolysaccharides (EPS) produced by lactic acid bacteria are molecules of great interest for the dairy food industry. Lacticaseibacillus paracasei CIDCA 8339, CIDCA 83123, and CIDCA 83124 are potentially probiotic strains isolated from kefir grains whose EPS-production on MRS broth is dependent on incubation temperature. The aim of the present work is to evaluate the effect of fermentation temperature on the characteristics of EPS produced in milk by L. paracasei strains and the consequent impact on the rheological properties of the fermented products. Additionally, the protective effect of these EPS against Salmonella infection was evaluated in vitro. Acid gels with each strain were obtained by milk fermentation at 20°C, 30°C, and 37°C evidencing for all the strains a reduction in growth and acidification rate at lower temperature. Lacticaseibacillus paracasei CIDCA 83123 showed low fermentation rate at all temperatures requiring between 3 and 8 days to obtain acids gels, whereas CIDCA 8339 and 83124 needed between 24 and 48 h even when the temperature was 20°C. Fermentation temperature led to changes in crude EPS characteristics of the three strains, observing an increase in the relative amount of the high molecular weight fraction when the fermentation temperature diminished. Additionally, EPS83124 and EPS83123 presented modifications in monosaccharide composition, with a reduction of rhamnose and an increase of amino-sugars as temperature rise. These changes in the structure of EPS83124 resulted in an increase of the apparent viscosity of milks fermented at 20°C (223 mPa.s) and 30°C (217 mPa.s) with respect to acid gels obtained at 37°C (167 mPa.s). In order to deepen the knowledge on EPS characteristics, monosaccharide composition of low and high molecular weight EPS fractions were evaluated. Finally, it was evidenced that the preincubation of intestinal epithelial cells Caco-2/TC-7 with EPS8339 and EPS83124 partially inhibit the association and invasion of Salmonella. In light of these results, it can be concluded that the selection of the EPS-producing strain along with the appropriate fermentation conditions could be an interesting strategy to improve the technological properties of these L. paracasei fermented milks with potential protective effects against intestinal pathogens.The present work was supported by CONICET (PIP 2786), Universidad Nacional de La Plata (UNLP 18/X813), ANPCyT (PICT 2020-03973 and PICT 2020-3239), and the Basque Government (IT1662-22 and PIBA 2020_1_0032)
Latest trends in industrial vinegar production and the role of acetic acid bacteria: classification, metabolism, and applications—a comprehensive review
Vinegar is one of the most appreciated fermented foods in European and Asian countries. In industry, its elaboration depends on numerous factors, including the nature of starter culture and raw material, as well as the production system and operational conditions. Furthermore, vinegar is obtained by the action of acetic acid bacteria (AAB) on an alcoholic medium in which ethanol is transformed into acetic acid. Besides the highlighted oxidative metabolism of AAB, their versatility and metabolic adaptability make them a taxonomic group with several biotechnological uses. Due to new and rapid advances in this field, this review attempts to approach the current state of knowledge by firstly discussing fundamental aspects related to industrial vinegar production and then exploring aspects related to AAB: classification, metabolism, and applications. Emphasis has been placed on an exhaustive taxonomic review considering the progressive increase in the number of new AAB species and genera, especially those with recognized biotechnological potential
Colour implications of self-association processes of wine anthocyanins
[EN] Copigmentation processes have been indicated to be crucial to stabilise coloured forms of the anthocyanins and explain colour expression in young red wines. Several studies exist about copigmentation between anthocyanins and different phenolics in model solutions, but little information is available about interactions among anthocyanins themselves. In this work, the process of self-association has been investigated in wine-like model solutions containing different grape anthocyanins (the 3-glucosides of malvidin, delphinidin and peonidin). The results obtained confirmed the existence of anthocyanin self-association and its influence on the apparent hydration constant of the anthocyanins with subsequent modification in the colour of the solutions. It was observed that the greater the degree of methoxylation of the anthocyanin B-ring the greater was the magnitude of the self-association. Colour analyses in the CIELAB space showed that self-association produces changes, which are more important in quantitative parameters (chroma, C ab* and lightness, L *) than in qualitative ones (hue, h ab). Self-association leads to an increase in C ab*, indicating a more intense colour of the solutions, and to a decrease in the psychometric index L *, meaning that a darkening is produced. The effects on the colour were more pronounced with the passage of time of storage of the solutions
Studies on the copigmentation between anthocyanins and flavan-3-ols and their influence in the colour expression of red wine
[ES] With the aim of evaluating the importance of the copigmentation process between anthocyanins and
flavanols on the colour expression of red wine, assays were carried out in wine model systems with mixtures of compounds obtained from two Vitis vinifera grape varieties (Graciano and Tempranillo). Spectrophotometric and chromatic analyses were performed to evaluate the magnitude of the copigmentation and the modifications induced in the colour of the solutions. Measurement of the changes in the anthocyanin hydration constant (Kh) was also used to determine the strength of the copigmentation process.
All the flavanols assayed induced significant changes in the colour, perceptible to the human eye, of the wine-like anthocyanin solutions at concentrations similar to those that can exist in red wines. The percentage contribution of the copigmentation with flavanols to the colour of the anthocyanin solutions was found to range from 2% to 20%. The extent of this effect was related not only to the concentration of flavanols but also to the qualitative composition of the flavanol preparations, as influenced by the part of the grape (either skin or seed) and the variety considered. Divergences were found between the evaluation of the copigmentation based on chromatic parameters in the CIELAB colour space and that based on the measurement at visible kmax, as the latter does not consider the integral colour changes produced in the visible spectrum. The results obtained confirmed the importance of the qualitative phenolic composition, determined in the wine by the type of grape and winemaking practices, to the production of an effective copigmentation process
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