Food Science and Human Wellness最新文献

Atherosclerosis, as the most prevalent form of cardiovascular disease, is characterized by oxidized low-density lipoprotein (ox-LDL) accumulation in the vascular wall, increased inflammation of the large arteries, dysfunction of the endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), which may eventually lead to the formation of plaques. Xanthophylls, one of the main groups of carotenoids, have been proposed as preventive agents or adjunct therapies to prevent and slow the progression of atherosclerosis due to their cardioprotective properties. However, the underlying preventive mechanism of action of xanthophylls on the pathogenesis of atherosclerosis remains unclear, and clinical evidence of the effect of xanthophylls on atherosclerosis have not yet been summarized and critically reviewed. In this regard, we conducted a comprehensive literature search in four scientific databases (PubMed, Google Scholar, ScienceDirect and Web of Science) and carefully analyzed the existing evidence to provide meaningful insights on the association between xanthophylls and atherosclerosis from various aspects. Based on the evidence from in vitro and in vivo studies, we explored several potential mechanisms, including antioxidant effect, anti-inflammatory effect, regulation of lipid metabolism, and modulation of ECs and VSMCs dysfunction, and we found that a clear picture of regulatory pathways of xanthophylls on atherosclerosis prevention and treatment is still lacking. In addition, epidemiological studies suggested the possible relationship among high dietary intake of xanthophylls, high plasma/serum xanthophylls and a reduced risk of atherosclerosis. Direct evidence from interventional studies investigating the effect of xanthophylls on atherosclerosis is very sparse, whilst indirect clinical evidence was only limited to astaxanthin and lutein. Therefore, well-designed long-term randomized controlled trials (RCTs) are highly recommended for future studies to investigate the effective dose of different xanthophylls on atherosclerosis prevention and their possible ancillary effect in conjunction with drug therapies on different stages of atherosclerosis.

Obesity is associated with gut dysbiosis and metabolic endotoxin. Junshanyinzhen tea extract (JSTE) reduced fat accumulation and body weight in obese mice. However, the effects and mechanism of JSTE in preventing obesity were unclear. Therefore, we used different doses of JSTE (75, 150 and 300 mg/(kg∙d)) to evaluate the effect on high-fat diet (HFD)-induced rats under 8 weeks of intervention. Here, our results showed that JSTE could significantly reduce body weight gain, blood lipid levels and fat accumulation, improve fatty damage in liver tissue (P < 0.05). In addition, JSTE increased the expression of intestinal tight junction proteins (P < 0.05), relieved metabolic endotoxemia (P < 0.05) and chronic low-grade inflammation in HFD rats. Sequencing of fecal samples showed that JSTE could effectively reverse the microbial diversity and the ratio of Firmicutes to Bacteroidetes to normal levels in HFD-fed rats. Desulfovibrioceae and Erysipelotrichaceae, which are positively related to obesity, were decreased by JSTE intervention (P < 0.05). while Bifidobacteriaceae, Bacteroidaceae, Akkermansia, and Clostridium, which are negatively related to obesity, were increased. Together, these results suggested that JSTE might effectively prevent obesity by modulating gut microbiota dysbiosis, intestinal barrier dysfunction, metabolic endotoxemia and chronic low-grade inflammation in HFD-induced rats.

Sensitive detection of Staphylococcus aureus enterotoxin B (SEB) is of importance for preventing food poisoning from threatening human health. In this work, an electrochemical and colorimetric dual-signal detection assay of SEB was developed. The probe (Ab2/AuPt@Fe-N-C) was bound to SEB captured by Ab1, where the Ab2/AuPt@Fe-N-C triggered methylene blue degradation and resulted in the decrease of electrochemical signal. Furthermore, the probe catalyzed the oxidation of 3,3’,5,5’-tetramethyl biphenyl to generate a colorimetric absorbance at 652 nm. Once the target was captured and formed a sandwich-like complex, the color changed from colorless to blue. SEB detection by colorimetric and electrochemical methods showed a linear relationship in the concentration ranges of 0.000 2–10.000 0 and 0.000 5–10.000 0 ng/mL, with limits of detection of 0.066 7 and 0.167 0 pg/mL, respectively. The dual-signal biosensor was successfully used to detect SEB in milk and water samples, which has great potential in toxin detection in food and the environment.

Highland barley (HB) is a high-altitude cereal with rich nutritional components and potential health benefits. To clarify its hypoglycemic effect and mechanism, we investigated the effect of whole grain HB and fecal microbiota transplantation (FMT) on glucose metabolism and gut microbiota in high-fat diet and streptozotocin (HFD/STZ)-induced diabetic mice. The results showed that HB (40 %) significantly decreased fasting blood glucose and the area under the glucose tolerance curve, significantly increased insulin secretion and improved insulin resistance in HFD/STZ-induced diabetic mice (P < 0.05). Inflammatory factors and blood lipid indices were also significantly alleviated after 12 weeks of 40 % HB intervention (P < 0.05). Additionally, beneficial bacteria, such as Bifidobacterium and Akkermansia, were significantly enriched in the gut of diabetic mice after whole grain HB intervention. Meanwhile, the results of further FMT experiments verified that the fecal microbiota after the 40 % HB intervention not only significantly increased the relative abundance of Bifidobacterium and Akkermansia but also effectively improved glucose metabolism and alleviated the inflammatory state in HFD/STZ-induced diabetic mice. Collectively, our study confirmed the bridge role of gut microbiota in improving glucose metabolism of whole grain HB, which could promote the development of precision nutrition.

Alpha-lactalbumin (α-LA) is a major whey protein found in breast milk and plays a crucial role in the growth and development of infants. In this study, Bacillus subtilis RIK1285 harboring AprE signal peptide (SP) was selected as the original strain for the production of α-LA. It was found that α-LA was identified in the pellet after ultrasonic disruption and centrifugation instead of in the fermentation supernatant. The original strain most likely only produced α-LA intracellular, but not extracellular. To improve the expression and secretion of α-LA in RIK1285, a library of 173 homologous SPs from the B. subtilis 168 genome was fused with target LALBA gene in the pBE-S vector and expressed extracellularly in RIK1285. SP YjcN was determined to be the best signal peptide. Bands in supernatant were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and purified by nickel column to calculate the highest yield signal peptide. In addition, different promoters (P_aprE, P₄₃, and P_glv) were compared and applied. The results indicated that the strain RIK1285-pBE-P_glv-YjcN-LALBA had the highest α-LA yield, reaching 122.04 μg/mL. This study demonstrates successful expression and secretion of human α-LA in B. subtilis and establishes a foundation for simulating breast milk for infant formulas and developing bioengineered milk.