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The aim of this study is to characterize the bioactivity of mycelial biomass and crude exopolysaccharides (EPS) produced by Trametes versicolor NBIMCC 8939 and to reveal its nutraceutical potential. The EPS (1.58 g/L) were isolated from a culture broth. The macrofungal biomass was rich in protein, insoluble dietary fibers and glucans. The amino acid composition of the biomass was analyzed and 18 amino acids were detected. Three mycelial biomass extracts were prepared and the highest total polyphenol content (16.11 ± 0.14 mg GAE/g DW) and the total flavonoid content (5.15 ± 0.03 mg QE/g DW) were found in the water extract. The results indicated that the obtained EPS were heteropolysaccharides with glucose as the main building monosaccharide and minor amounts of mannose, xylose, galactose, fucose and glucuronic acid. Fourier Transform Infrared Spectroscopy (FTIR) confirmed the complex structure of the crude EPS. Five probiotic lactic acid bacteria strains were used for the determination of the prebiotic effect of the crude EPS. The anti-inflammatory potential was tested in vitro using cell line HT-29. The significant decrease of IL-1 and IL-8 and increase of TGF-beta expression revealed anti-inflammatory potential of the crude exopolysaccharides from T. versicolor.

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Esta obra, editada por José María Infante Bonfiglio y María Eugenia Flores Treviño, recoge doce trabajos de investigación presentados en el VI Coloquio Internacional del Programa EDICE (Estudios sobre el Discurso de la Cortesía en Español), celebrado en 2011 en Monterrey (México). Dichos trabajos aparecen organizados en tres partes, dedicadas respectivamente a estudios sobre imagen y (des)cortesía, actos de habla y (des)cortesía y atenuación.Los autores cuyas investigaciones integran este libro asumen que la (des) cortesía varía de una cultura a otra, y, por tanto, se basan en postulados teóricos de pragmática sociocultural. En este sentido, adquieren gran importancia las nociones de Bravo (otros trabajos), quien enriqueció las categorías analíticas básicas antecedentes de carácter universalista, dando cuenta de la importancia de los factores de variación sociocultural en los estudios de (des)cortesía.Al inicio, los editores ofrecen una reflexión sobre ciertas deficiencias tanto formales como conceptuales prototípicas en estudios de esta índole, tales como la falta de consenso entre los investigadores en cuanto a la metodología y la terminología empleadas. Se defiende la necesidad de contemplar la concepción que se tiene de determinados valores culturales a la hora de abordar los estudios sobre (des)cortesía. Asimismo, critican el hecho de que la mayoría de los estudiosos se aferren excesivamente a las teorías de autores precedentes para avalar sus investigaciones. Esta crítica se centra en aquellos trabajos fundamentados en los postulados universalistas de Brown y Levinson (1987), los cuales no pueden sostenerse, según los autores, si se examinan los avances de la teoría social de las últimas décadas (p. 11).La primera parte de la obra se abre con un trabajo de Carmen Curcó Cobos, en el que se defiende la postura contraria. Esta autora aboga por el conservadurismo metodológico. Sin dejar de otorgar importancia a la consideración de valores culturales, apuesta por no abandonar la clásica noción de imagen pública. Seguidamente, hace un recorrido bibliográfico por trabajos de autores -9786072703285

The aim of the present study was to analyse the type of adhesive factors of selected probiotic strains. A large number of lactic acid bacteria with intestinal and dairy origin were collected and assessed for adhesion on Caco-2 cell line. From the best adherent bacteria, four strains were selected for further research: Lactobacillus gasseri G7, L. plantarum F1, L. helveticus AC and L. delbrueckii subsp. bulgaricus B14. The average number of adhered bacteria was 17 per one Caco-2 cell in the case of L. gasseri G7 and 21 per cell in the case of L. plantarum F1. Treatment with ethylenediaminetetraacetic acid (EDTA), trypsin and metaperiodic acid in separate assays revealed that cell-bonded extracellular proteins were responsible for the adhesion of the selected L. gasseri, L. plantarum and L. helveticus strains, in contrast to the L. delbrueckii subsp. bulgaricus strain, whose adhesive factors were identified as cell-bonded exopolysaccharides. The cell-wall proteins from the first three strains were isolated, fractionated and assessed for adhesion to Caco-2 cells. Based on the attachment properties of the purified proteins towards Caco-2 cells, it was clearly proved exactly which proteins are involved in the adherence. L. plantarum F1 strain contains two adhesive proteins in contrast to the other selected strains containing one adhesive protein each. The determination of the factors mediating the adhesive abilities of the selected strains provides important information about the possible ways to preserve and increase adhesive properties towards epithelium cells.

Lactobacillus gasseri within the Lactobacillus acidophilus group is a major species in the human microflora. The potential probiotic properties of a L. gasseri strain of human origin were evaluated. Out of 17 studied L. gasseri strains, L. gasseri 4/13 showed the highest immunomodulatory effect (induction of interferon gamma measured by sandwich enzyme-linked immunosorbent assay) in Balb/c mouse splenocytes in vitro and the highest rate of adhesion to Caco-2 human epithelial cells. The strain also reduced the concentration of cholesterol in the growth medium by 65% as compared with the initial concentration (measured spectrophotometrically). These probiotic properties indicate that L. gasseri 4/13 could prove an attractive concentrated adjunct monoculture in the production of new functional foods. To obtain a freeze-dried bacterial concentrate from L. gasseri 4/13, the influence of different culture media, temperatures and pH values on the accumulation of cell biomass was studied. Yoghurt samples were produced using a classical fermentation technology. Freeze-dried concentrated monoculture of L. gasseri 4/13 with over 1 × 1010 CFU/g viable cells was added as an adjunct culture together with a starter. The viable L. gasseri 4/13 cells remained above the critical value of 106 CFU/g during storage at 5 °C for the entire 20-day period. Organoleptic tests did not reveal any adverse change in the product taste and aroma of yoghurt samples at the 20th day. In conclusion, L. gasseri 4/13 was selected as having suitable probiotic and cultural characteristics for production of fermented milk products with high nutritional and biological value.

Some lactic acid bacteria strains in milk media are capable of releasing bioactive peptides. In this study, we evaluated the angiotensin-converting enzyme (ACE)inhibitory activity of 180 lactic acid bacteria and selected several Lactobacillus helveticus, L. delbrueckii subsp. bulgaricus and L. casei strains that demonstrated strong ACE-inhibitory activity. The aim was to carry out a molecular study on the bioactive peptides released by the strains with the best ACE-inhibitory properties and by the strains demonstrating a calcium-binding effect. To the best of our knowledge, this is the first study of bioactive peptides in Bulgarian white cheese. Peptides with the strongest ACE-inhibitory activity were purified and sequenced. The strains were assessed for production of peptides with calcium-binding properties. These peptides were isolated, purified and sequenced. Two strains releasing bioactive peptides with the strongest ACE-inhibitory and calcium-binding activities were selected for development of cheese starters. The strain with the best ACE-inhibitory activity was L. helveticus A1, which releases the peptide Ala-Leu-Pro-Met as a main contributor to the ACE inhibition. The strain with the best calcium-binding activity was L. casei C3 releasing the peptide SpLSpSpSpE (fraction 15–20 of ß-casein) as a main contributor to calcium binding. After pilot production of cheeses with the developed starters, the ACE-inhibitory and calcium-binding effects were confirmed during the cheese ripening. The addition of the two selected adjunct cultures led to increased production of bioactive peptides in the cheese. In this way, it is possible to increase the functional properties of Bulgarian white brined cheese.

This study aimed to assess potential feeding effect of camel milk curd mass and its mixes to experimental rat’s blood serum biochemical parameters, enzymatic activity and the peptide toxicity. Fifty healthy male Sprague-Dawley rats were divided into five groups (n = 10 each). Each group was fed with camel milk pure curd mass and its mixes for 16 days. At the end of the experiment, rats were sacrificed to collect the samples from the blood serum. Blood serum biochemical parameters total protein, cholesterol, glucose, albumin, triglycerides; the enzymatic activities of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase were determined on the A25 automatic analyser, and peptide toxicity analysed by the reference method. The statistical data have shown no significant differences in body weight gain in all groups. Total protein decreased in group II, IV, and V; however, it increased in group III compared to the control group. Cholesterol grew up in group II and it slightly increased in group V, dropped in groups III and IV compared to group I result. Glucose increased in groups II, III, IV compared to group I; still, group V results show a slight decrease. Albumin decreased in group IV, yet in group V it increased than the group I result. Simultaneously, groups II and III results were changed with less percentage. Triglyceride grew up in groups II, V, and it dropped significantly in groups III, IV compared to the control group. De Ritis ratio of enzymes in groups II, III, and IV fluctuated between 1.31 and 0.98 IU/L; however, group V demonstrated significant data versus group I. Diets peptide toxicity in all groups was lower than control group data. The experimental results indicated that curd mass from camel milk could be used as a pure or with additives and it did not discover the observed side effects.