Purification, structure and immunobiological activity of an arabinan-rich pectic polysaccharide from the cell walls of prunus dulcis seeds

The structure and bioactivity of a polysaccharide extracted and purified from a 4MKOH + H3BO3 solution from Prunus dulcis seed cell wall material was studied. Anion-exchange chromatography of the crude extract yielded two sugar-rich fractions: one neutral (A), the other acidic (E). These fractions contain a very similar monosaccharide composition: 5:2:1 for arabinose, uronic acids and xylose, respectively, rhamnose and galactose being present in smaller amounts. As estimated by size-exclusion chromatography, the acidic fraction had an apparent molecular mass of 762kDa. Methylation analysis (from the crude and fractions A and E), suggests that the polysaccharide is an arabinan-rich pectin. In all cases, the polysaccharides bear the same type of structural Ara moieties with highly branched arabinan-rich pectic polysaccharides. The average relative proportions of the arabinosyl linkages is 3:2:1:1 for T-Araf:(1!5)-Araf:(1!3,5)-Araf:(1!2,3,5)-Araf. The crude polysaccharide extract and fractions A and E induced a murine lymphocyte stimulatory effect, as evaluated by the in vitro and in vivo expression of lymphocyte activation markers and spleen mononuclear cells culture proliferation. The lymphocyte stimulatory effect was stronger on B- than on T-cells. No evidence of cytotoxic effects induced by the polysaccharide fractions was found.Fundação para a Ciência e Tecnologia (FCT) - PRAXIX XXI/BD/18401/98

Sweet whey cheese matrices inoculated with the probiotic strain Lactobacillus paracasei LAFTI® L26

Consumption of dairy products containing viable probiotic strains has increased dramatically in recent years, owing to general health claims associated therewith. This trend has boosted diversification of the portfolio of said products, including whey cheese matrices. However, taking into account the relatively poor organoleptic and textural features of these matrices, improvement is in order via incorporation of selected additives, provided that viability of the strains is duly assayed. Lactobacillus paracasei LAFTI® L26 was accordingly incorporated into whey protein solid matrices, in the presence of several additives aimed at enhancing their organoleptic appeal and textural performance. These matrices were produced from a combination of either ovine or bovine whey (or a mixture thereof) with ovine milk, and were inoculated at 10% (v/v) with the probiotic strain. Sugar, sugar and aloe vera, sugar and chocolate, and sugar and jam were further added, and the resulting products were then stored at 7 ◦C for 21 d. In general, viable cell numbers remained high in all experimental matrices throughout storage. Despite the observed low extents of breakdown, proteolytic activities by the end of storage were higher in matrices containing jam. Furthermore, L. paracasei partially converted lactose into lactic acid in these matrices. Additives enhanced the organoleptic features of whey cheeses, and produced different textural patterns. The higher sensory scores were attained by matrices containing sugar: sugar and aloe vera received the best scores by 3 d of storage, but these scores decreased as storage time elapsed

Fresh-cut melon quality during storage: an NMR study of water transverse relaxation time

Molecular mobility is a fundamental parameter which reflects the dynamic properties of food components and contributes to food degradation reactions comprehension. Fresh-cut fruits have become an important food market segment. However, processing of fruits promotes faster its physiological deterioration, biochemical changes and microbial degradation. The purpose of this work was to use NMR methodology as a tool to evaluate fresh-cut fruit quality, during storage at refrigerated conditions. The fresh-cut melon transverse relaxation time (T2) was measured for a period of 7 days of storage at 5 °C. The relationship between the obtained values, microstructure and quality parameters was investigated. In general, results show the existence of one class of water fluidity in the system, the one present in cells after processing. T2, a measure of this fluidity, is affected by the processing and storage time. Also, it is possible to find a close relationships between T2 and quality parameters of total colour difference (TCD), firmness and aw. As T2 increases TCD also increases, while firmness and aw decrease. These results highlight the usefulness of NMR methodology application in food science.Author Joana F. Fundo acknowledges Fundacao para a Ciencia e a Tecnologia (grant SFRH/BD/62176/2009). The authors acknowledge the Portuguese NMR Network and Strategic Project PEst-C/CTM/LA0025/2013-14. This work was supported by National Funds from FCT through project PEst-OE/EQB/LA0016/201

Effect of diets with different non-starch polysaccharides profiles on gilthead seabream (Sparus aurata) growth and appetite regulation

Plant feedstuffs are the most established alternative to fish meal in the feed industry but although being readily available and economically viable, the presence of non-starch polysaccharides (NSPs) might impair their use. Accounting the NSP profile of plant feedstuffs, a gilthead seabream (Sparus aurata) growth trial was run testing five isolipidic and isoproteic plant feedstuffs-based diets with 30% inclusion levels of soybean rapeseed, sunflower, or a mixture of these ingredients (10% each), and a control diet with none of those ingredients. Growth and nutritional performance were assessed, and intestinal short chain fatty acids (SCFAs) were estimated as an indicator of gut microbiota metabolism. Moreover, appetite- related gene expression was evaluated in the hypothalamus, stomach, liver, and anterior intestine. No mortality was recorded during the study, and no significant differences in growth parameters, feed utilization, body composition, and visceral somatic index were found among dietary treatments. Hepatosomatic index, lipid retention, and liver lipid composition results highlighted the role of dietary carbohydrates in liver lipid deposition, being significantly higher in fish fed the Control diet which possessed the highest starch level. Acetate was the only SCFA detected with significantly higher concentration in the gut content of fish fed the Sunflower and Mix diets than in fish fed the Control and Rapeseed diets. Regarding appetite- related gene expression in hypothalamus, cocaine and amphetamine regulated transcript, neuropeptide Y and agouti-related peptide presented the same expression across treatments. In liver and stomac significant differences were not detected for leptin and ghrelin expression, respectively. In the anterior intestine, despite cholecystokinin relative gene expression did not present significant difference, it underlined a similar trend to peptide YY where Soybean, Sunflower, and Mix diets presented significantly higher relative gene expression than in fish fed Control diet. In conclusion, gilthead seabream presented a good performance when fed the plant feedstuffs- based diets rich in dietary fiber and NSPs. The diverse plant feedstuffs-based mixtures affected specific metabolic pathways, and microbial metabolism potentially affected appetite-related gene expression.info:eu-repo/semantics/publishedVersio

Study of in vitro digestion of Tenebrio molitor flour for evaluation of its impact on the human gut microbiota

Human diet has evolved to include not only nutritious foods but also health-promoting ones. Moreover, there is an increasing interest in replacing animal proteins as the main protein source. Insect based foods, e.g. Tenebrio molitor insect flour (TMIF), show potential as alternative protein sources for the human diet. This work aims to provide insights into the effect of TMIF upon the human gut microbiota and their metabolic end products by using an in vitro fecal model. Digested TMIF had a positive impact on gut microbiota, observed as an increase and/or upkeep of health promoting bacterial groups and by the production of SCFA (1.7 and 2.6 times higher acetate and propionate produced respectively than in the negative control at 48 h) and BCFA. A path is opened to acknowledge TMIF as a possible healthy nutritional source for human consumption, although in vivo trials would be necessary to confirm this

Genetic variability and natural selection at the ligand domain of the Duffy binding protein in Brazilian Plasmodium vivax populations.

Background. Plasmodium vivax malaria is a major public health challenge in Latin America, Asia and Oceania, with 130-435 million clinical cases per year worldwide. Invasion of host blood cells by P. vivax mainly depends on a type I membrane protein called Duffy binding protein (PvDBP). The erythrocyte-binding motif of PvDBP is a 170 amino-acid stretch located in its cysteine-rich region II (PvDBPII), which is the most variable segment of the protein. Methods. To test whether diversifying natural selection has shaped the nucleotide diversity of PvDBPII in Brazilian populations, this region was sequenced in 122 isolates from six different geographic areas. A Bayesian method was applied to test for the action of natural selection under a population genetic model that incorporates recombination. The analysis was integrated with a structural model of PvDBPII, and T- and B-cell epitopes were localized on the 3-D structure. Results. The results suggest that: (i) recombination plays an important role in determining the haplotype structure of PvDBPII, and (ii) PvDBPII appears to contain neutrally evolving codons as well as codons evolving under natural selection. Diversifying selection preferentially acts on sites identified as epitopes, particularly on amino acid residues 417, 419, and 424, which show strong linkage disequilibrium. Conclusions. This study shows that some polymorphisms of PvDBPII are present near the erythrocyte-binding domain and might serve to elude antibodies that inhibit cell invasion. Therefore, these polymorphisms should be taken into account when designing vaccines aimed at eliciting antibodies to inhibit erythrocyte invasion

Genotoxic agents promote the nuclear accumulation of annexin A2: role of annexin A2 in mitigating DNA damage

Annexin A2 is an abundant cellular protein that is mainly localized in the cytoplasm and plasma membrane, however a small population has been found in the nucleus, suggesting a nuclear function for the protein. Annexin A2 possesses a nuclear export sequence (NES) and inhibition of the NES is sufficient to cause nuclear accumulation. Here we show that annexin A2 accumulates in the nucleus in response to genotoxic agents including gamma-radiation, UV radiation, etoposide and chromium VI and that this event is mediated by the nuclear export sequence of annexin A2. Nuclear accumulation of annexin A2 is blocked by the antioxidant agent N-acetyl cysteine (NAC) and stimulated by hydrogen peroxide (H2O2), suggesting that this is a reactive oxygen species dependent event. In response to genotoxic agents, cells depleted of annexin A2 show enhanced phospho-histone H2AX and p53 levels, increased numbers of p53-binding protein 1 nuclear foci and increased levels of nuclear 8-oxo-2'-deoxyguanine, suggesting that annexin A2 plays a role in protecting DNA from damage. This is the first report showing the nuclear translocation of annexin A2 in response to genotoxic agents and its role in mitigating DNA damage.Natural Sciences and Engineering Research Council of Canada (NSERC); European Union [PCOFUND-GA-2009-246542]; Foundation for Science and Technology of Portugal; Beatrice Hunter Cancer Research Institute; Terry Fox Foundationinfo:eu-repo/semantics/publishedVersio

The burden of mental disorders, substance use disorders and self-harm among young people in Europe, 1990–2019: Findings from the Global Burden of Disease Study 2019

BACKGROUND: Mental health is a public health issue for European young people, with great heterogeneity in resource allocation. Representative population-based studies are needed. The Global Burden of Disease (GBD) Study 2019 provides internationally comparable information on trends in the health status of populations and changes in the leading causes of disease burden over time. METHODS: Prevalence, incidence, Years Lived with Disability (YLDs) and Years of Life Lost (YLLs) from mental disorders (MDs), substance use disorders (SUDs) and self-harm were estimated for young people aged 10-24 years in 31 European countries. Rates per 100,000 population, percentage changes in 1990-2019, 95% Uncertainty Intervals (UIs), and correlations with Sociodemographic Index (SDI), were estimated. FINDINGS: In 2019, rates per 100,000 population were 16,983 (95% UI 12,823 – 21,630) for MDs, 3,891 (3,020 - 4,905) for SUDs, and 89·1 (63·8 - 123·1) for self-harm. In terms of disability, anxiety contributed to 647·3 (432–912·3) YLDs, while in terms of premature death, self-harm contributed to 319·6 (248·9–412·8) YLLs, per 100,000 population. Over the 30 years studied, YLDs increased in eating disorders (14·9%;9·4-20·1) and drug use disorders (16·9%;8·9-26·3), and decreased in idiopathic developmental intellectual disability (–29·1%;23·8-38·5). YLLs decreased in self-harm (–27·9%;38·3-18·7). Variations were found by sex, age-group and country. The burden of SUDs and self-harm was higher in countries with lower SDI, MDs were associated with SUDs. INTERPRETATION: Mental health conditions represent an important burden among young people living in Europe. National policies should strengthen mental health, with a specific focus on young people. FUNDING: The Bill and Melinda Gates Foundatio