Antioxidant Capacity of Cotyledons and Germs of Soybeanb in Relation to Their Isoflavone Content

Svrha je ovog istraživanja bila proučiti odnos antioksidativnog kapaciteta i udjela izoflavona u ekstraktu soje s obzirom na geografsko podrijetlo i kultivar. Uzorci soje uzeti su iz dva dijela zrna soje, klice i kotiledona, s dvaju zemljopisnih lokacija (L1 i L2) i iz dva kultivara (Queen i Imari), ukupno 8 različitih uzoraka. HPLC metoda potvrdila je veći udio izoflavona u klicama nego u kotiledonima, i to u uzorcima s lokacije L2 i u kultivaru Queen. Antioksidativni kapacitet uzoraka soje određen je dvjema metodama, uklanjanjem 2,2\u27- difenil-1-pikrilhidrazil radikala i određivanjem sposobnosti apsorpcije kisikovih radikala. Rezultati obiju metoda pokazali su veću antioksidativnu aktivnost ekstrakta klice od ekstrakta kotiledona.The aim was to study the relationship between the antioxidant capacity and the isoflavone content of soybean extracts depending on both geographic origin and cultivar. Soybean samples were obtained from two soybean seed parts, germ and cotyledon, from two geographical locations (L1, L2) and two cultivars (Queen, Imari), which gave 8 different samples. HPLC determination confirmed higher isoflavone content in germs than in cotyledons, with higher contents in site L2, and in the Queen cultivar. The antioxidant capacity of soybean samples was determined with two methods, the 2,2-diphenyl-1-picrylhydrazyl scavenging assay and the oxygen radical absorbance capacity assay. The results obtained with both assays showed differences in antioxidant capacity between germ and cotyledon extracts, with a higher antioxidant activity of germ extracts

Metabolic adaptation to a high-fat diet is associated with a change in the gut microbiota

Objective The gut microbiota, which is considered a causal factor in metabolic diseases as shown best in animals, is under the dual influence of the host genome and nutritional environment. This study investigated whether the gut microbiota per se, aside from changes in genetic background and diet, could sign different metabolic phenotypes in mice. Methods The unique animal model of metabolic adaptation was used, whereby C57Bl/6 male mice fed a high-fat carbohydrate-free diet (HFD) became either diabetic (HFD diabetic, HFD-D) or resisted diabetes (HFD diabetes-resistant, HFD-DR). Pyrosequencing of the gut microbiota was carried out to profile the gut microbial community of different metabolic phenotypes. Inflammation, gut permeability, features of white adipose tissue, liver and skeletal muscle were studied. Furthermore, to modify the gut microbiota directly, an additional group of mice was given a glucooligosaccharide (GOS)-supplemented HFD (HFD+GOS). Results Despite the mice having the same genetic background and nutritional status, a gut microbial profile specific to each metabolic phenotype was identified. The HFD-D gut microbial profile was associated with increased gut permeability linked to increased endotoxaemia and to a dramatic increase in cell number in the stroma vascular fraction from visceral white adipose tissue. Most of the physiological characteristics of the HFD-fed mice were modulated when gut microbiota was intentionally modified by GOS dietary fibres. Conclusions The gut microbiota is a signature of the metabolic phenotypes independent of differences in host genetic background and diet

Effects of sodium nitrite reduction, removal or replacement on cured and cooked meat for microbiological growth, food safety, colon ecosystem, and colorectal carcinogenesis in Fischer 344 rats

Epidemiological and experimental evidence indicated that processed meat consumption is associated with colorectal cancer risks. Several studies suggest the involvement of nitrite or nitrate additives via N-nitroso-compound formation (NOCs). Compared to the reference level (120 mg/kg of ham), sodium nitrite removal and reduction (90 mg/kg) similarly decreased preneoplastic lesions in F344 rats, but only reduction had an inhibitory effect on Listeria monocytogenes growth comparable to that obtained using the reference nitrite level and an effective lipid peroxidation control. Among the three nitrite salt alternatives tested, none of them led to a significant gain when compared to the reference level: vegetable stock, due to nitrate presence, was very similar to this reference nitrite level, yeast extract induced a strong luminal peroxidation and no decrease in preneoplastic lesions in rats despite the absence of NOCs, and polyphenol rich extract induced the clearest downward trend on preneoplastic lesions in rats but the concomitant presence of nitrosyl iron in feces. Except the vegetable stock, other alternatives were less efficient than sodium nitrite in reducing L. monocytogenes growth

Les isoflavones du soja dans la filière aliment santé

Plusieurs études ont mis en évidence les propriétés alicamenteuses des isoflavones du soja. Ces propriétés leur confèrent un potentiel de prévention vis-à-vis des maladies cardio-vasculaires, de certains cancers et des problèmes en lien avec la ménopause. Cependant, des influences néfastes au niveau, notamment, du développement reproducteur et de la fertilité de plusieurs espèces animales ont été établies. Des différences de biodisponibilité et de métabolisme de ces composés bioactifs ont été observées entre individus mais également entre les différentes isoflavones du soja (12 isoflavones différentes ont été isolées dans les graines et les produits à base de soja). Par ailleurs, plusieurs facteurs en lien avec le génotype et le milieu de culture influencent la teneur et la composition de ces composés dans la graine. Enfin, les procédés de production affectent également la teneur et/ou la composition en isoflavones dans les produits à base de soja

Bifidobacterium longum and Lactobacillus helveticus synergistically suppress stress-related visceral hypersensitivity through hypothalamic-pituitary-adrenal axis modulation

Visceral pain and hypothalamic-pituitary-adrenal axis (HPA) dysregulation is a common characteristic in irritable bowel syndrome (IBS) patients. Previously, we reported that a probiotic formulation (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175) prevents chronic stress-mediated brain function abnormalities by attenuating the HPA axis response. Here, we compared the effect between different probiotic treatments on the perception of visceral pain during colorectal distension (CRD) following a chronic stress and the consequences to the activity of the HPA axis. After a 2-week treatment with a combined probiotic formulation, or L. helveticus or B. longum alone in stressed mice, the visceral pain in response to CRD was recorded. The expression of glucocorticoid receptors was determined in the different brain areas involved in the stress response (hypothalamus, hippocampus, and prefrontal cortex). The plasma levels of stress hormones were also measured. A pretreatment using the combination of probiotic formulation significantly reduces the chronic stress-induced visceral hypersensitivity respectively at 0.06, 0.08, and 0.10 mL CRD volume. However, a single probiotic (B. longum or L. helveticus) administration is less effective in reducing visceral pain in stressed mice. Moreover, the expression of the glucocorticoid receptor mRNA was consistently up-regulated in several brain areas after pretreatment with a combined probiotic, which correlated with the normalization of stress response compared to the inconsistent effects of a single probiotic. The combination of L. helveticus and B. longum is more effective in regulating glucocorticoid negative feedback on the HPA axis than probiotic alone and subsequently in treating stress-induced visceral pain

Mucus: An Underestimated Gut Target for Environmental Pollutants and Food Additives

Synthetic chemicals (environmental pollutants, food additives) are widely used for many industrial purposes and consumer-related applications, which implies, through manufactured products, diet, and environment, a repeated exposure of the general population with growing concern regarding health disorders. The gastrointestinal tract is the first physical and biological barrier against these compounds, and thus their first target. Mounting evidence indicates that the gut microbiota represents a major player in the toxicity of environmental pollutants and food additives; however, little is known on the toxicological relevance of the mucus/pollutant interplay, even though mucus is increasingly recognized as essential in gut homeostasis. Here, we aimed at describing how environmental pollutants (heavy metals, pesticides, and other persistent organic pollutants) and food additives (emulsifiers, nanomaterials) might interact with mucus and mucus-related microbial species; that is, “mucophilic” bacteria such as mucus degraders. This review highlights that intestinal mucus, either directly or through its crosstalk with the gut microbiota, is a key, yet underestimated gut player that must be considered for better risk assessment and management of environmental pollution

Changes in intestinal glucocorticoid sensitivity in early life shape the risk of epithelial barrier defect in maternal-deprived rats.

Glucocorticoids (GC) contribute to human intestine ontogeny and accelerate gut barrier development in preparation to birth. Rat gut is immature at birth, and high intestinal GC sensitivity during the first two weeks of life resembles that of premature infants. This makes suckling rats a model to investigate postpartum impact of maternal separation (MS)-associated GC release in preterm babies, and whether GC sensitivity may shape MS effects in immature gut. A 4 hours-MS applied once at postnatal day (PND)10 enhanced plasma corticosterone in male and female pups, increased by two times the total in vivo intestinal permeability (IP) to oral FITC-Dextran 4 kDa (FD4) immediately after the end of MS, and induced bacterial translocation (BT) to liver and spleen. Ussing chamber experiments demonstrated a 2-fold increase of permeability to FD4 in the colon immediately after the end of MS, but not in the ileum. Colonic permeability was not only increased for FD4 but also to intact horseradish peroxidase 44 kDa in MS pups. In vivo, the glucocorticoid receptor (GR) antagonist RU486 or ML7 blockade of myosin light chain kinase controlling epithelial cytoskeleton contraction prevented MS-induced IP increase to oral FD4 and BT. In addition, the GR agonist dexamethasone dose-dependently mimicked MS-increase of IP to oral FD4. In contrast, MS effects on IP to oral FD4 and BT were absent at PND20, a model for full-term infant, characterized by a marked drop of IP to FD4 in response to dexamethasone, and decreased GR expression in the colon only compared to PND10 pups. These results show that high intestinal GC responsiveness in a rat model of prematurity defines a vulnerable window for a post-delivery MS, evoking immediate disruption of epithelial integrity in the large intestine, and increasing susceptibility to macromolecule passage and bacteremia