The Utilization by Bacteroides spp. of a Purified Polysaccharide from Fuzhuan Brick Tea.

In the present study, four Bacteroides species that could degrade Fuzhuan brick tea polysaccharide-3 (FBTPS-3) were isolated from human feces and identified to be Bacteroides ovatus, B. uniformis, B. fragilis and B. thetaiotaomicron. The four Bacteroides species showed growth on FBTPS-3 as the carbon source, and B. ovatus showed the best capability for utilizing FBTPS-3 among the four species since B. ovatus could utilize more FBTPS-3 during 24 h fermentation. Moreover, the four Bacteroides species could metabolize FBTPS-3 and promote the production of acetic, propionic and isovaleric acids. Transcriptome analysis of B. ovatus revealed that 602 genes were up-regulated by FBTPS-3, including two carbohydrate-active enzyme clusters and four polysaccharide utilization loci (PULs). The PUL 1 contained GH28 family that could hydrolyze rhamnogalacturonan and other pectic substrates, which was in line with our previous work that rhamnose and galacturonic acid were the main component monosaccharides of FBTPS-3. Collectively, the results suggested that FBTPS-3 could be utilized by Bacteroides spp., and it might be developed as a promising prebiotic targeting Bacteroidetes in intestinal environment.

Zirconium­cerium modified polyvinyl alcohol/NaCMC biocomposite film: Synthesis of films through high-speed shear assisted technique and removal fluoride from water.

A new zirconium and cerium-modified polyvinyl alcohol (PVA) sodium carboxymethyl cellulose (NaCMC) film (PVA/CMC-Zr-Ce) was synthesized thru a high-speed shear-assisted method and its adsorption for the removal of fluoride was studied, in which the NaCMC provided -COONa for ion exchange between Na and Zr-Ce, thus the loading amount of Zr-Ce on films was accordingly increased. The morphology and structure of PVA/CMC-Zr-Ce were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Besides, the mechanical properties, water contact angle, and swelling ratio of film were also evaluated. The addition of high-speed shear improved the dispersion of the emulsion system, and PVA/CMC-Zr-Ce film with good adsorption performance and film stability was prepared. While, it was found that the adsorption capacity could reach 67.25 mg/g and equilibrium time could reach 20 min. The adsorption mechanism of PVA/CMC-Zr-Ce revealed that ion exchange between hydroxide and fluoride, electrostatic interactions and complexation were the dominating influencing factors. Based on these findings, it can be concluded that PVA/CMC-Zr-Ce film- synthesized with high-speed shear assistance technique is a promising adsorbent for fluoride removal from water.

Alleviation of fluoride-induced colitis by tea polysaccharides: Insights into the role of Limosilactobacillus vaginalis and butyric acid.

Endemic fluorosis has gained increasing attention as a public health concern, and the escalating risk of colitis resulting from excessive fluoride intake calls for effective mitigation strategies. This study aimed to investigate the potential mechanisms underlying the alleviation of fluoride-induced colitis by Tea polysaccharides (TPS). Under conditions of excessive fluoride intake, significant changes were observed in the gut microbiota of rats, leading to aggravated colitis. However, the intervention of TPS exerted a notable alleviating effect on colitis symptoms. Antibiotic intervention and fecal microbiota transplantation (FMT) experiments provided evidence that TPS-mediated relief of fluoride-induced colitis is mediated through its effects on the gut microbiota. Furthermore, TPS supplementation was found to modulate the structure of gut microbiota, enhance the relative abundance of Limosilactobacillus vaginalis in the gut microbiota, and promote the expression of short-chain fatty acid (SCFAs) receptors in colonic tissue. Notably, L. vaginalis played a significant role in alleviating fluoride-induced colitis and facilitating the absorption of butyric acid in the rat colon. Subsequent butyric acid intervention experiments confirmed its remarkable alleviating effect on fluoride-induced colitis. Overall, these findings provide a potential preventive strategy for fluoride-induced colitis by TPS intervention, which is mediated by L. vaginalis and butyric acid.

L-Theanine Prolongs the Lifespan by Activating Multiple Molecular Pathways in Ultraviolet C-Exposed Caenorhabditis elegans.

L-theanine, a unique non-protein amino acid, is an important bioactive component of green tea. Previous studies have shown that L-theanine has many potent health benefits, such as anti-anxiety effects, regulation of the immune response, relaxing neural tension, and reducing oxidative damage. However, little is known concerning whether L-theanine can improve the clearance of mitochondrial DNA (mtDNA) damage in organisms. Here, we reported that L-theanine treatment increased ATP production and improved mitochondrial morphology to extend the lifespan of UVC-exposed nematodes. Mechanistic investigations showed that L-theanine treatment enhanced the removal of mtDNA damage and extended lifespan by activating autophagy, mitophagy, mitochondrial dynamics, and mitochondrial unfolded protein response (UPRmt) in UVC-exposed nematodes. In addition, L-theanine treatment also upregulated the expression of genes related to mitochondrial energy metabolism in UVC-exposed nematodes. Our study provides a theoretical basis for the possibility that tea drinking may prevent mitochondrial-related diseases.

Dietary polyphenols regulate appetite mechanism via gut-brain axis and gut homeostasis.

Nowadays, due to the rise of fast-food consumption, the metabolic diseases are increasing as a result of high-sugar and high-fat diets. Therefore, there is an urgent need for natural, healthy and side-effect-free diets in daily life. Whole grain supplementation can enhance satiety and regulate energy metabolism, effects that have been attributed to polyphenol content. Dietary polyphenols interact with gut microbiota to produce intermediate metabolites that can regulate appetite while also enhancing prebiotic effects. This review considers how interactions between gut metabolites and dietary polyphenols might regulate appetite by acting on the gut-brain axis. In addition, further advances in the study of dietary polyphenols and gut microbial metabolites on energy metabolism and gut homeostasis are summarized. This review contributes to a better understanding of how dietary polyphenols regulate appetite via the gut-brain axis, thereby providing nutritional references for citizens' dietary preferences.

Microencapsulation as a Protective Strategy for Sialylated Immunoglobulin G: Efficacy in Alleviating Symptoms of Dextran Sulfate Sodium-Induced Colitis in Mice and Potential Mechanisms.

Sialylated immunoglobulin G (IgG) is a vital glycoprotein in breast milk with the ability to promote the growth of Bifidobacterium in gut microbiota and relieve inflammatory bowel disease (IBD) symptoms in vitro. Here, it was found that the microcapsules with sialylated IgG could protect and release sialylated IgG with its structure and function in the intestine. Furthermore, the sialylated IgG microcapsules alleviated the clinical symptoms (body weight, feed quantity, and colon length loss), decreased disease activity index score, suppressed the production of pro-inflammatory cytokines (TNF-α, IL-6, IL-1ß, IFN-γ, and MCP-1) and endotoxin (lipopolysaccharide), and enhanced the intestinal mucosal barrier (Claudin1, Muc2, Occludin, and ZO-1) in dextran sulfate sodium (DSS)-induced colitis mice. Additionally, the sialylated IgG microcapsules improved the gut microbiota by increasing the relative abundance of critical microbe Bifidobacterium bifidum and promoted the production of short-chain fatty acids (SCFAs). Correlation analysis indicated that the key microbes were strongly correlated with pro-inflammatory factors, clinical symptoms, tight junction protein, and SCFAs. These findings suggest that the sialylated IgG microcapsules have the potential to be used as a novel therapeutic approach for treating IBD.

Improvement of oxidized myofibrillar protein gel properties by black rice extract.

In order to investigate the effects of black rice extract (BE) on the composition of oxidized myofibrillar protein (MP) gel, different concentrations of BE (0, 10, 20, 50 mg g-1) were analyzed experimentally. Results revealed that the addition of small doses of BE significantly inhibited the formation of carbonyl groups in oxidized MP, and improved surface hydrophobicity and gel water holding capacity. Additionally, 10 and 20 mg g-1 BE increased the ordered structure of oxidized MP. Furthermore, dynamic rheometer results showed a significant increase in the storage modulus (G') of oxidized MP with 10 and 20 mg g-1 BE during heating. Scanning Electron Microscopy (SEM) showed that MP formed a denser network structure with addition of 10 and 20 mg g-1 BE. Low-Field Nuclear Magnetic Resonance (LF-NMR) and magnetic resonance imaging (MRI) showed that there is a significant increase in immobile water in MP gel and a decrease in free water within the 20 mg g-1 BE group. In conclusion, 20 mg g-1 supplemented BE significantly improved the structure order and hardness of oxidized MP gel, increased its structure density and water holding capacity, and it provides a theoretical basis for the application of antioxidants in meat products.

Selenium foliar application contributes to decrease ratio of water-soluble fluoride and improve physio-biochemical components in tea leaves.

The tea plant accumulates elevated levels of fluoride (F) from environmental sources. Drinking tea containing high F levels poses a potential threat to human health. Selenium (Se) was applied by foliar spray to investigate its effects on F accumulation and physiology in tea plant. Foliar application of different forms of Se, i.e., Na2SeO3, Kappa-selenocarrageenan, Selenomethionine and Nanoselenium, reduced F content in tea leaves by 10.17 %-44.28 %, 16.12 %-35.41 %, 22.19 %-45.99 % and 22.24 %-43.82 %, respectively. Foliar spraying Se could increase F accumulation in pectin through increasing pectin content and pectin demethylesterification to bind more F in the cell wall, which decreased the proportion of water-soluble fluoride in tea leaves. Application of Se significantly decreased the contents of chromium (39.6 %-72.0 %), cadmium (48.3 %-84.4 %), lead (2.2 %-44.4 %) and copper (14.1 %-44.6 %) in tea leaves. Foliar spraying various forms of Se dramatically increased the Se content and was efficiently transformed into organic Se accounting for more than 80 % in tea leaves. All Se compounds increased peroxidase activity by 3.3 %-35.5 % and catalase activity by 2.6 %-99.4 %, reduced malondialdehyde content by 5.6 %-37.1 %, and increased the contents of chlorophyll by 0.65 %-31.8 %, carotenoids by 0.24 %-27.1 %, total catechins by 1.6 %-21.0 %, EGCG by 4.4 %-17.6 % and caffeine by 9.1 %-28.6 %. These results indicated that Se application could be served as a potential efficient and safe strategy diminishing the concentration of F in tea leaves.

The polysaccharides from Auricularia auricula alleviate non-alcoholic fatty liver disease via modulating gut microbiota and bile acids metabolism.

The polysaccharides from Auricularia auricula (AAPs), containing a large number of O-acetyl groups that are related to the physiological and biological properties, seem to be potential prebiotics like other edible fungus polysaccharides. In the present study, therefore, the alleviating effects of AAPs and deacetylated AAPs (DAAPs, prepared from AAPs by alkaline treatment) on nonalcoholic fatty liver disease (NAFLD) induced by high-fat and high-cholesterol diet combined with carbon tetrachloride were investigated. The results revealed that both AAPs and DAAPs could effectively relieve liver injury, inflammation and fibrosis, and maintain intestinal barrier function. Both AAPs and DAAPs could modulate the disorder of gut microbiota and altered the composition of gut microbiota with enrichment of Odoribacter, Lactobacillus, Dorea and Bifidobacterium. Further, the alteration of gut microbiota, especially enhancement of Lactobacillus and Bifidobacterium, was contributed to the changes of bile acids (BAs) profile with increased deoxycholic acid (DCA). Farnesoid X receptor could be activated by DCA and other unconjugated BAs, which participated the BAs metabolism and alleviated the cholestasis, then protected against hepatitis in NAFLD mice. Interestingly, it was found that the deacetylation of AAPs negatively affected the anti-inflammation, thereby reducing the health benefits of A. auricula-derived polysaccharides.

Intracellular Polysaccharides of Aspergillus cristatus from Fuzhuan Brick Tea Leverage the Gut Microbiota and Repair the Intestinal Barrier to Ameliorate DSS-Induced Colitis in Mice.

The intracellular polysaccharides of Aspergillus cristatus (IPSs) from Fuzhuan brick tea have been demonstrated to improve immune function linked to modulating the gut microbiota. Herein, to further investigate the efficacy of IPSs to maintain gut homeostasis, the protection of the purified fraction of IPSs (IPSs-2) on the mice with colitis induced by dextran sulfate sodium (DSS) and the underlying mechanisms were explored in this study. The results revealed that IPSs-2 alleviated the typical symptoms of colitis and suppressed the excessive inflammatory mediators, regulating the genes related to inflammatory responses in the colon at the mRNA level. Meanwhile, IPSs-2 treatment reinforced the intestinal barrier function by ameliorating the DSS-induced histological injury, facilitating the differentiation of goblet cells to enhance Mucin-2 generation, and enhancing the expression of tight junction proteins to alleviate colitis. In addition, IPSs protected against colitis by promoting the production of short-chain fatty acids (SCFAs), the activation of SCFAs receptors, and the leverage of the gut microbiota via the enrichment of Bacteroides, Parabacteroides, Faecalibacterium, Flavonifractor_plautii, and Butyricicoccus, linking with reducing inflammation and repairing intestinal barrier function. Overall, our research revealed the therapeutic potential of IPSs-2 as a prebiotic for attenuating inflammatory bowel disease and provided a rationale for future investigation.

The types of brewing water affect tea infusion flavor by changing the tea mineral dissolution.

The effects of different brewing water samples, including natural drinking water (NDW), pure water (PW), mineral water (MW), distilled water (DW), and tap water (TW) on flavor and quality of green tea infusion were investigated. The results showed the dissolution rate of mineral substances varied greatly depend on the type of water used. Notably, the tea infusion brewed with MW showed the highest taste response and darker but higher brightness in color. Furthermore, the content of volatile compounds was highest in tea infusion brewed with NDW and lowest in tea infusion brewed with MW. The mineral substances content and pH were the main factors affecting volatile compounds in green tea infusion. Thereinto, Ca2+ and Fe3+ remarkably affected the content of alcohols and aldehydes in volatile compounds. These results suggested that water with a neutral pH value and lower mineral substance content is more conducive for brewing green tea.

Anthocyanins from Lycium ruthenicum Murray Ameliorated High-Fructose Diet-Induced Neuroinflammation through the Promotion of the Integrity of the Intestinal Barrier and the Proliferation of Lactobacillus.

In the present study, we found that anthocyanins from Lycium ruthenicum Murray (ACN) potently ameliorated a high-fructose diet (HFrD)-induced neuroinflammation in mice. ACN improved the integrity of the intestinal barrier and suppressed the toll-like receptor 4 (TLR4) signaling pathway to ameliorate the neuroinflammation, which was verified by Tlr4-/- mice. Furthermore, ACN could modulate the HFrD-induced dysbiosis of gut microbiota. The fecal microbiota transplantation from ACN-induced mice was sufficient to attenuate the neuroinflammation, while the amelioration of neuroinflammation by ACN was blocked upon gut microbiota depletion. In addition, ACN-induced increment of the relative abundance of Lactobacillus might be responsible for the alleviation of the neuroinflammation, which was further confirmed in the promoting effect of ACN on the growth of Lactobacillus in vitro. Overall, these results provided the evidence of a comprehensive cross-talk mechanism between ACN and neuroinflammation in HFrD-fed mice, which was mediated by reducing gut microbiota dysbiosis and maintaining the intestinal barrier integrity.

A critical review of Fuzhuan brick tea: processing, chemical constituents, health benefits and potential risk.

Fuzhuan brick tea (FBT) is a traditional popular beverage in the border regions of China. Nowadays, FBT has been attracted great attention due to its uniquely flavor and various health-promoting functions. An increasing number of efforts have been devoted to the studies on health benefits and chemistry of FBT over the last decades. However, FBT was still received much less attention than green tea, oolong tea and black tea. Therefore, it is necessary to review the current encouraging findings about processing, microorganisms, chemical constituents, health benefits and potential risk of FBT. The fungus fermentation is the key stage for processing of FBT, which is involved in a complex and unique microbial fermentation process. The fungal community in FBT is mainly dominated by "golden flower" fungi, which is identified as Aspergillus cristatus. A great diversity of novel compounds is formed and identified after a series of biochemical reactions during the fermentation process of FBT. FBT shows various biological activities, such as antioxidant, anti-inflammatory, anti-obesity, anti-bacterial, and anti-tumor activities. Furthermore, the potential risk of FBT was also discussed. It is expected that this review could be useful for stimulating further research of FBT.

A new natural drying method for food packaging and preservation using biopolymer-based dehydration film.

A new method for the drying of beef and chicken meats at low temperatures (4 °C) was developed by using a composite film based on sodium carboxymethyl cellulose-gum Arabic (SG) with anthocyanins from Cinnamomum camphora fruit peel (ANC.P, 0, 1, 1.5 and 2%). After incorporation of ANC.P into SG, the physicochemical properties, morphological characteristics, melting, molecular, antioxidant and antimicrobial properties of the resulting dehydration films were improved. Film-dried beef and chicken slices showed higher values of dehydration ratio on day 6 (54.58% and 72.06%, respectively) compared with the control samples without film (4.55% and 7.04%, respectively). Results showed that SG-ANC.P film-dried meats exhibited more stable pH and color, higher rehydration rate, better sensory quality and microbial growth inhibition compared with SG film-dried samples and control samples, in which control samples showed the highest total viable count values (6.02 and 5.16 log CFU/mL for beef and chicken, respectively) during storage.

Effects of long-term administration of theasinensin A on healthy C57BL/6J mice: Enhancing the function of epididymal white adipose tissue and regulating the colonic microenvironment.

The effects of theasinensin A (TSA) on healthy C57BL/6J mice were investigated. Results showed that long-term administration of 100 mg/kg body weight/day TSA might be non-toxic to healthy mice based on the unaltered basal biochemical indicators related to glucose and lipid metabolism, inflammatory factors and hepatic injury. On the contrary, TSA stimulated the rate of lipid turnover and browning of white adipose tissues, accelerated the adipocytic energy mobilization, and then reduced the white adipocytic size, ultimately enhancing resistance to obesity in healthy mice. Furthermore, TSA not only up-regulated the expression of mucin, tight junction protein, and short-chain fatty acids receptor, but also regulated the intestinal microbiota by enhancing the typical beneficial microbe Akkermansia muciniphila, thereby modulating the colonic microenvironment. These results suggested that TSA had a potential strengthening effect on the resistance of healthy mice to metabolic disorders, which provides a theoretical basis for the utilization of TSA.

Fluoride induced leaky gut and bloom of Erysipelatoclostridium ramosum mediate the exacerbation of obesity in high-fat-diet fed mice.

INTRODUCTION: Fluoride is widely presented in drinking water and foods. A strong relation between fluoride exposure and obesity has been reported. However, the potential mechanisms on fluoride-induced obesity remain unexplored. Objectives and methods The effects of fluoride on the obesity were investigated using mice model. Furthermore, the role of gut homeostasis in exacerbation of the obesity induced by fluoride was evaluated. Results The results showed that fluoride alone did not induce obesity in normal diet (ND) fed mice, whereas, it could trigger exacerbation of obesity in high-fat diet (HFD) fed mice. Fluoride impaired intestinal barrier and activated Toll-like receptor 4 (TLR4) signaling to induce obesity, which was further verified in TLR4-/- mice. Furthermore, fluoride could deteriorate the gut microbiota in HFD mice. The fecal microbiota transplantation from fluoride-induced mice was sufficient to induce obesity, while the exacerbation of obesity by fluoride was blocked upon gut microbiota depletion. The fluoride-induced bloom of Erysipelatoclostridium ramosum was responsible for exacerbation of obesity. In addition, a potential strategy for prevention of fluoride-induced obesity was proposed by intervention with polysaccharides from Fuzhuan brick tea. Conclusion Overall, these results provide the first evidence of a comprehensive cross-talk mechanism between fluoride and obesity in HFD fed mice, which is mediated by gut microbiota and intestinal barrier. E. ramosum was identified as a crucial mediator of fluoride induced obesity, which could be explored as potential target for prevention and treatment of obesity with exciting translational value.

Characterization and In Vitro Antioxidant and Anti-Inflammatory Activities of Ginsenosides Extracted from Forest-Grown Wild Panax quinquefolius L.

American ginseng (Panax quinquefolius L.) is known for its health benefits, which are attributed to various terpenoids. However, the specific composition and activities of these terpenoids in forest-grown wild American ginseng remain understudied. This study aimed to characterize the terpenoid composition, particularly triterpene saponins, in forest-grown wild American ginseng. The analysis revealed that triterpene saponins, notably American ginseng ginsenosides (AGGs), are the predominant active components, as identified through LC-MS/MS and HPLC. A subsequent in vitro evaluation of AGGs showcased their potent antioxidant capabilities, displaying the dose-dependent scavenging of free radicals and reducing agents. Moreover, AGGs demonstrated efficacy in reducing oxidative injury and intracellular ROS levels in RAW 264.7 macrophages treated with H2O2. In addition to their antioxidant properties, AGGs exhibited anti-inflammatory effects, significantly inhibiting NO and inflammatory substance production in lipopolysaccharide-treated RAW 264.7 macrophages. These findings highlight the potential of AGG-rich forest-grown wild American ginseng as a functional food with promising implications for improving human health.

Effects of arabinoxylan and chlorogenic acid on the intestinal microbiota in dextran sulfate sodium-treated mice.

Dietary non-starch polysaccharides and phenolics are usually ingested at the same time. They are both regarded as prebiotics, and they regulate the intestinal microbiota through various mechanisms. Notably, however, reports of their combined or synergistic effects are rare. Arabinoxylan (AX), a polysaccharide, and chlorogenic acid (CA), a polyphenol, are widely consumed, and their effects on the microbiota have previously been discussed. In the present study, they were given to dextran sulfate sodium (DSS)-treated mice, separately and together, and the intestinal microbiota were investigated by high-throughput sequencing. The data showed that CA attenuated body weight loss, colon shortening, and histological damage in DSS-treated mice, while neither AX nor the AX+CA combination exhibited any ameliorating potential. AX+CA had less of a modulating effect on intestinal microbiota profiles than did CA. AX+CA administration increased the relative abundance of Flavonifractor, Coprobacillus, and Clostridium_XlVa, and decreased the abundance of Robinsoniella and Lactobacillus. Compared to AX and CA, AX+CA contributed to a more complicated shift in the biological functions of the intestinal microbiotaAX seemed to weaken the beneficial effects of CA, at least in the present experimental model of DSS-induced colitis. The combined effects and mechanisms of dietary polysaccharides and phenolic compounds on the intestinal microbiota and on overall health still need to be further investigated.

The polysaccharides from the fruits of Lycium barbarum L. modify the gut community profile and alleviate dextran sulfate sodium-induced colitis in mice.

In the present study, the effects of a purified fraction of polysaccharides from the fruits of Lycium barbarum L. (LBPs), named LBPs-4, on the dextran sodium sulfate (DSS)-induced colitis in mice were evaluated. The results showed that LBPs-4 decreased disease activity index score, prevented colon shortening and reduced plasma levels of pro-inflammatory cytokines (tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ), monocyte chemoattractant protein-1 (MCP-1) and prostaglandin E2) in mice with colitis. LBPs-4 could increase the relative abundances of Akkermansia and Bifidobacterium in gut microbiota, and it also mitigated the intestinal barrier damage by upregulating the level of tight junction protein ZO-1 and the number of goblet cells in colon. Moreover, the results of in vitro culture indicated that the growth of Bifidobacterium longum subsp. infantis CCX 19042 was promoted by LBPs-4, whereas the culture media of LBPs-4 by Bacteroides ovatus with or without addition of mucin could enhance the growth of Akkermansia muciniphila. Collectively, these results suggested that LBPs-4 should be potential prebiotics for the treatment of colitis.

Study on the Interaction between Four Typical Carotenoids and Human Gut Microflora Using an in Vitro Fermentation Model.

Recent studies indicated a strong relationship between carotenoids and gut microflora. However, their structure-activity relationship remains unclear. This study evaluated the interaction between four typical carotenoids (ß-carotene, lutein, lycopene, and astaxanthin) and gut microflora using an in vitro fermentation model. After 24 h of fermentation, the retention rates of the four carotenoids were 1.40, 1.38, 1.46, and 5.63 times lower than those of their without gut microflora control groups, respectively. All four carotenoid treated groups significantly increased total short-chain fatty acids (SCFAs) production. All carotenoid supplements significantly promoted the abundance of Roseburia and Parasutterella and inhibited the abundance of Collinsella, while ß-carotene, lutein, lycopene, and astaxanthin significantly promoted the abundance of Ruminococcus, Sutterella, Subdoligranulum, and Megamonas, respectively. Furthermore, xanthophylls have a more significant impact on gut microflora than carotenes. This study provides a new way to understand how carotenoids work in the human body with the existing gut microflora.