Impact of Phlorotannin Extracts from Fucus vesiculosus on Human Gut Microbiota

Recent studies indicate that plant polyphenols could be pointed as potential prebiotic candidates since they may interact with the gut microbiota, stimulating its growth and the production of metabolites. However, little is known about the fate of brown seaweeds’ phlorotannins during their passage throughout the gastrointestinal tract. This work aimed to evaluate the stability and bioaccessibility of Fucus vesiculosus phlorotannins after being submitted to a simulated digestive process, as well as their possible modulatory effects on gut microbiota and short-chain fatty acids production following a fermentation procedure using fecal inoculates to mimic the conditions of the large intestine. The stability of phlorotannins throughout the gastrointestinal tract was reduced, with a bioaccessibility index between 2 and 14%. Moreover, slight alterations in the growth of certain commensal bacteria were noticed, with Enterococcus spp. being the most enhanced group. Likewise, F. vesiculosus phlorotannins displayed striking capacity to enhance the levels of propionate and butyrate, which are two important short-chain fatty acids known for their role in intestinal homeostasis. In summary, this work provides valuable information regarding the behavior of F. vesiculosus phlorotannins along the gastrointestinal tract, presenting clear evidence that these compounds can positively contribute to the maintenance of a healthy gastrointestinal condition.     

Looking Beyond the Terrestrial: The Potential of Seaweed Derived Bioactives to Treat Non-Communicable Diseases

Seaweeds are a large and diverse group of marine organisms that are commonly found in the maritime regions of the world. They are an excellent source of biologically active secondary metabolites and have been shown to exhibit a wide range of therapeutic properties, including anti-cancer, anti-oxidant, anti-inflammatory and anti-diabetic activities. Several Asian cultures have a strong tradition of using different varieties of seaweed extensively in cooking as well as in herbal medicines preparations. As such, seaweeds have been used to treat a wide variety of health conditions such as cancer, digestive problems, and renal disorders. Today, increasing numbers of people are adopting a “westernised lifestyle” characterised by low levels of physical exercise and excessive calorific and saturated fat intake. This has led to an increase in numbers of chronic Non-communicable diseases (NCDs) such as cancer, cardiovascular disease, and diabetes mellitus, being reported. Recently, NCDs have replaced communicable infectious diseases as the number one cause of human mortality. Current medical treatments for NCDs rely mainly on drugs that have been obtained from the terrestrial regions of the world, with the oceans and seas remaining largely an untapped reservoir for exploration. This review focuses on the potential of using seaweed derived bioactives including polysaccharides, antioxidants and fatty acids, amongst others, to treat chronic NCDs such as cancer, cardiovascular disease and diabetes mellitus.     

Anti-Obesity and Gut Microbiota Regulation Effects of Phospholipids from the Eggs of Crab,Portunus Trituberculatus,in High Fat Diet-Fed Mice

There are resourceful phospholipids in the eggs of the crab, Portunus trituberculatus (Pt-PL). However, their components and bioactivities regarding obesity were unclear. Here, we investigated the composition of Pt-PL and their fatty acids. Moreover, its effects on obesity and gut microbiota were also evaluated in high fat diet (HFD)-fed mice. The results showed that Pt-PL contained 12 kinds of phospholipids, mainly including phosphatidylcholine (PC, 32.28%), phosphatidylserine (PS, 26.51%), phosphatidic acid (PA, 19.61%), phosphatidylethanolamine (PE, 8.81%), and phosphatidylinositol (PI, 7.96%). Polyunsaturated fatty acids (PUFAs) predominated in the fatty acids components of Pt-PL, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Animal experiments demonstrated that Pt-PL significantly alleviated body weight gain, adipose gain, hepatic gain, fasting blood glucose, serum insulin, lipid levels in serum and the liver, and systematic inflammation in HFD-fed mice. Furthermore, Pt-PL regulated gut microbiota, especially in a dramatic reduction in the ratio of Firmicutes to Bacteroidetes at phylum level, as well as significant amelioration in their subordinate categories. Pt-PL reduced fecal lipopolysaccharide and total bile acids, and elevated fecal short chain fatty acid (SCFA) concentrations, particularly acetate and butyrate. These findings suggest that Pt-PL possesses anti-obesity effects and can alter gut microbiota owing to the abundance of PUFAs. Therefore, Pt-PL may be developed as an effective food supplement for anti-obesity and regulation of human gut health.     

Ameliorative Effects of Peptides Derived from Oyster (Crassostrea gigas) on Immunomodulatory Function and Gut Microbiota Structure in Cyclophosphamide-Treated Mice

The intestinal flora is recognized as a significant contributor to the immune system. In this research, the protective effects of oyster peptides on immune regulation and intestinal microbiota were investigated in mice treated with cyclophosphamide. The results showed that oyster peptides restored the indexes of thymus, spleen and liver, stimulated cytokines secretion and promoted the relative mRNA levels of Th1/Th2 cytokines (IL-2, IFN-γ, IL-4 and IL-10). The mRNA levels of Occludin, Claudin-1, ZO-1, and Mucin-2 were up-regulated, and the NF-κB signaling pathway was also activated after oyster peptides administration. Furthermore, oyster peptides treatment reduced the proportion of Firmicutes/Bacteroidetes, increased the relative abundance of Alistipes, Lactobacillus, Rikenell and the content of short-chain fatty acids, and reversed the composition of intestinal microflora similar to that of normal mice. In conclusion, oyster peptides effectively ameliorated cyclophosphamide-induced intestinal damage and modified gut microbiota structure in mice, and might be utilized as a beneficial ingredient in functional foods for immune regulation.     

Seaweed Polysaccharides (Laminarin and Fucoidan) as Functional Ingredients in Pork Meat: An Evaluation of Anti-Oxidative Potential,Thermal Stability and Bioaccessibility

The anti-oxidative potential of laminarin (L), fucoidan (F) and an L/F seaweed extract was measured using the DPPH free radical scavenging assay, in 25% pork (longissimus thoracis et lumborum (LTL)) homogenates (TBARS) (3 and 6 mg/mL) and in horse heart oxymyoglobin (OxyMb) (0.1 and 1 mg/mL). The DPPH activity of fresh and cooked minced LTL containing L (100 mg/g; L₁₀₀), F₁₀₀ and L/F_100,300, and bioaccessibility post in vitro digestion (L/F₃₀₀), was assessed. Theoretical cellular uptake of antioxidant compounds was measured in a transwell Caco-2 cell model. Laminarin displayed no activity and fucoidan reduced lipid oxidation but catalysed OxyMb oxidation. Fucoidan activity was lowered by cooking while the L/F extract displayed moderate thermal stability. A decrease in DPPH antioxidant activity of 44.15% and 36.63%, after 4 and 20 h respectively, indicated theoretical uptake of L/F antioxidant compounds. Results highlight the potential use of seaweed extracts as functional ingredients in pork.     

饮用金花香橼茶3个月对小样本高脂血症人群糖脂代谢的改善效果研究

探讨一款用黑茶工艺、经冠突散囊菌发花的乌龙茶——金花香橼茶饮用3个月对小样本高脂血症人群糖脂代谢的临床改善效果。招募38名志愿者,试饮金花香橼茶3个月,通过检测和对比试饮前后的体成分（体重、体脂百分比等）、血液生化指标（空腹血糖、血尿酸、血脂四项）、肝脏超声、肠道菌群等,探讨金花香橼茶的健康功效。结果表明,试饮金花香橼茶3个月后,志愿者体重、体质指数、体脂百分比、内脏脂肪等级、血清总胆固醇、低密度脂蛋白胆固醇、空腹血糖显著降低（P<0.05）,脂肪肝严重程度减轻,肠道菌群均匀性和多样性增加,考拉杆菌属（Phascolarctobacterium）、瘤胃球菌属（Ruminococcus）、嗜血杆菌属（Haemophilus）、韦荣球菌属（Veillonella）等丰度升高,戴阿利斯特杆菌属（Dialister）、丁酸蓖麻单胞菌属（Butyricimonas）丰度降低。提示金花香橼茶具有辅助降血糖、降血脂、改善非酒精性脂肪肝的作用,可能通过增加产短链脂肪酸菌属的丰度,增加短链脂肪酸,改善胰岛素抵抗,进而改善糖脂代谢。本研究所得结果仍需更加严谨的长期试验进一步加以确证。