In vitro simulated colonic fermentation studies have shown the prebiotic potential of exopolysaccharides from Lactiplantibacillus plantarum YY-112(YEPS).Its immunomodulatory effects and related mechanisms were systema...In vitro simulated colonic fermentation studies have shown the prebiotic potential of exopolysaccharides from Lactiplantibacillus plantarum YY-112(YEPS).Its immunomodulatory effects and related mechanisms were systematically investigated in this study.We observed that YEPS intervene in immune responses and improve intestinal microbial structure in normal mice,including significantly increasing the relative abundance of Enterorhabdus and norank_f_norank_o_Clostridia UCG-014 as well as decreasing that of unclassified_c_Bacilli(P<0.05).In the immunocompromised mouse model,YEPS decreased interleukin-6 levels(P<0.05)and protected the spleen by regulating lymphocyte levels.YEPS preserved the intestinal barrier by improving Mucin 2,Zonula occludens protein 1,and Occludin expression.Moreover,YEPS significantly reduced the relative abundance of Bacillus,unclassified_c_Bacilli,Lachnoclostridium,Eubacterium_xylanophilum_group,and Desulfovibrio(P<0.05),potentially enhancing mice immunity by improving the intestinal microbiota associated with immune function.In conclusion,YEPS can be used as a natural functional extract with prebiotic effects that may improve host immunity.This provided the basis for the application of YEPS as a novel potential food additive.展开更多
Lactic acid bacteria(LAB)exopolysaccharides(EPS)reveal high safety and multiple activities,and are typical postbiotics produced by LAB during fermentation.In this paper,6583 articles on LAB-EPS from Web of Science and...Lactic acid bacteria(LAB)exopolysaccharides(EPS)reveal high safety and multiple activities,and are typical postbiotics produced by LAB during fermentation.In this paper,6583 articles on LAB-EPS from Web of Science and Elsevier databases were retrieved,and 236 articles related to this review were screened.The EPS from 90 LAB strains were summarized in terms of their extraction methods,yield,molecular weight,monosaccharide composition,glycosidic bond configuration and the structural and activity relationships(SARs).However,there exist great challenges as for the low yield and high cost in EPS production.Therefore,this review further elaborated the mechanism of EPS secretion,the anabolic pathway of EPS,the structure and mechanism of key enzymes involving in EPS synthesis process,the prospect of gene regulation for EPS secretion,and proposed the engineering strategies for increasing EPS yield or tailored EPS design in recent years.In addition,CRISPR/Cas9 gene editing technology was also discussed in the production control of EPS in LAB.Finally,the engineering strategy of increasing EPS yield in recent years was proposed.This work might provide important theoretical support for the production and application of LAB-based EPS.展开更多
Microbial polysaccharides represent a class of important products of growing interest for many sectors of indus- try. In recent years, there has been a growing interest in isolating new exopolysaccharides (EPSs)-produ...Microbial polysaccharides represent a class of important products of growing interest for many sectors of indus- try. In recent years, there has been a growing interest in isolating new exopolysaccharides (EPSs)-producing bacteria from marine environments, particularly from various extreme marine environments. Many new marine microbial EPSs with novel chemical compositions, properties and structures have been found to have potential applications in fields such as adhesives, textiles, Pharmaceuticals and medicine for anti-cancer, food additives, oil recovery and metal removal in mining and indus- trial waste treatments, etc This paper gives a brief summary of the information about the EPSs produced by marine bacteria, including their chemical compositions, properties and structures, together with their potential applications in industry.展开更多
Background Salmonella typhimurium(S.T),as an important foodborne bacterial pathogen,can cause diarrhea and gastroenteritis in humans and animals.Numerous studies have confirmed that exopolysaccharides(EPSs)have variou...Background Salmonella typhimurium(S.T),as an important foodborne bacterial pathogen,can cause diarrhea and gastroenteritis in humans and animals.Numerous studies have confirmed that exopolysaccharides(EPSs)have various biological functions,but the mechanism through which EPSs improve the immunity of animals against the invasion of pathogenic bacteria is unclear.Here,we explored the protective effect of EPSs of Lactobacillus rhamnosus GG(LGG)on the S.T-infected intestine.Methods Mice received adequate food and drinking water for one week before the start of the experiment.After 7 d of prefeeding,2×108 CFU/mL S.T solution and an equivalent volume of saline(control group)were given orally for 1 d.On the fourth day,the mice were treated with 0.5 mg/mL EPSs,1.0 mg/mL EPSs,2.0 mg/mL EPSs,or 2.0 mg/mL penicillin for 7 d.Finally,the body and relative organ weight,histological staining,and the levels of antioxidant enzyme activity and inflammatory cytokines were determined.Results The S.T-infected mice exhibited symptoms of decreased appetite,somnolence,diarrhea and flagging spirit.Treatment with EPSs and penicillin improved the weight loss of the mice,and the high dose of EPSs showed the best therapeutic effect.EPSs significantly ameliorated S.T-induced ileal injury in mice.High-dose EPSs were more effective than penicillin for alleviating ileal oxidative damage induced by S.T.The mRNA levels of inflammatory cytokines in the ileum of mice showed that the regulatory effects of EPSs on inflammatory cytokines were better than those of penicillin.EPSs could inhibit the expression and activation of key proteins of the TLR4/NF-κB/MAPK pathway and thereby suppress the level of S.T-induced ileal inflammation.Conclusions EPSs attenuate S.T-induced immune responses by inhibiting the expression of key proteins in the TLR4/NF-κB/MAPK signaling pathway.Moreover,EPSs could promote bacterial aggregation into clusters,which may be a potential strategy for reducing the bacterial invasion of intestinal epithelial cells.展开更多
<span style="line-height:1.5;"><span style="font-family:Verdana;">An antioxidant is a substance that inhibits the oxidation of other molecules caused by free radicals. The inbuilt antio...<span style="line-height:1.5;"><span style="font-family:Verdana;">An antioxidant is a substance that inhibits the oxidation of other molecules caused by free radicals. The inbuilt antioxidant systems possessed by living or</span><span style="font-family:Verdana;">g</span><span style="font-family:Verdana;">anisms are generally not enough to prevent them from oxidati</span><span style="font-family:Verdana;">ve damage</span><span style="font-family:Verdana;">s and the use</span></span><span style="line-height:1.5;font-family:Verdana;">s</span><span style="line-height:1.5;font-family:Verdana;"> of synthetic antioxidants also ha</span><span style="line-height:1.5;font-family:Verdana;">ve</span><span style="line-height:1.5;font-family:Verdana;"> some harmful effects. T</span><span style="line-height:1.5;"><span style="font-family:Verdana;">his study was aimed at evaluating the antioxidant activities of exopolysaccharides p</span><span style="font-family:Verdana;">roduced by lactic acid bacteria isolated from yoghurt. Lactic acid bac</span><span style="font-family:Verdana;">teria (LAB) were isolated from six different brands of commercially available yoghurt using deMan Rogosa Sharpe (MRS) agar. The LAB isolates were identified based on morphological and biochemical analyses and were screened for exopolysaccharide (EPS) production. The LAB isolates screened positive were used for EPS production in a liquid medium and the EPS produced were purified and quantified using standard methods. Antioxidant activities of the E</span><span style="font-family:Verdana;">PS were evaluated by determining the 1,1-dip</span><span style="font-family:Verdana;">henyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, ferric ion reducing power, and total phenolic contents. Data obtained were analysed using Analysis of Variance. Total lactic acid bacterial count obtained from the yoghurt samples ranged from 0 - 3.9 × 10</span><sup><span style="font-family:Verdana;">4</span></sup><span style="font-family:Verdana;"> CFU/mL with sample A (Fan Yoghurt) having the highest LAB count (3.9 × 10</span><sup><span style="font-family:Verdana;">4</span></sup><span style="font-family:Verdana;"> CFU/mL). The isolated LAB and their incidence rate were </span><i><span style="font-family:Verdana;">Lactobacillus plantarum </span></i><span style="font-family:Verdana;">(25.49%),</span><i><span style="font-family:Verdana;"> L. delbrueckii </span></i><span style="font-family:Verdana;">(19.61%),</span><i><span style="font-family:Verdana;"> L. fermentum </span></i><span style="font-family:Verdana;">(15.69%),</span><i><span style="font-family:Verdana;"> L. acidophilus </span></i><span style="font-family:Verdana;">(13.73%), </span><i><span style="font-family:Verdana;">Leuconostoc mesenteroides </span></i><span style="font-family:Verdana;">(11.76%),</span><i><span style="font-family:Verdana;"> Lactococcus lactis </span></i><span style="font-family:Verdana;">(7.84%), and </span><i><span style="font-family:Verdana;">Lactobacillus casei </span></i><span style="font-family:Verdana;">(5.88%). Fifty-one out of the 64 LAB isolates were screened positive for EPS production and only six were able to produce substantial quantity of EPS ranging from 127.4 - 208.5 mg/L. The exopolysaccharides produced by </span><i><span style="font-family:Verdana;">L. fermentum</span></i><span style="font-family:Verdana;"> had the highest DPPH radical scavenging activity (62.90%) while that of </span><i><span style="font-family:Verdana;">L. plantarum</span></i><span style="font-family:Verdana;"> had the lowest (23.10%) at a concentration of 1000 μg/mL. Also, the EPS produced by </span><i><span style="font-family:Verdana;">L. fermentum</span></i><span style="font-family:Verdana;"> recorded the highest ferric ion reducing power (12.89 mg AAE/mL) at 1000 μg/mL while that of </span><i><span style="font-family:Verdana;">L. plantarum</span></i><span style="font-family:Verdana;"> had the lowest (5.62 mg AAE/mL). At 1000 μg/mL, the total phenolic contents of the EPS samples ranged from 1.41 - 1.58 mg GAE/mL, and the EPS produced by </span><i><span style="font-family:Verdana;">L. fermentum </span></i><span style="font-family:Verdana;">had the highest (1.58 mg GAE/mL) while those produced by </span><i><span style="font-family:Verdana;">L. paracasei </span></i><span style="font-family:Verdana;">had the lowest (1.41 mg GAE/mL). This study revealed that the exopolysaccharides produced by the LAB isolates showed high antioxidant activities with respect to their DPPH free radical scavenging activity, ferric ion reducing power and total phenolic contents.展开更多
In this study, bacteria associated with marine organisms were screened for the production of exopolysaccharides（EPSs） on MY media containing sea salts（2.5%-10%）. Three selected isolates were identified as Alteromo...In this study, bacteria associated with marine organisms were screened for the production of exopolysaccharides（EPSs） on MY media containing sea salts（2.5%-10%）. Three selected isolates were identified as Alteromonas sp. PRIM-21, Nitratireductor sp. PRIM-24 and Enterobacter sp. PRIM-26 using 16 S r RNA gene sequencing. Optimization of the growth and EPS production kinetics in relation to incubation time were assessed. The purified EPS yield was 590, 650 and 540 mg·L-1 culture media respectively in Alteromonas sp. PRIM-21, Nitratireductor sp. PRIM-24 and Enterobacter sp. PRIM-26. Biochemical and FTIR analyses revealed the presence of biologically important functional groups in the EPS produced by all the three isolates. The EPS produced by Nitratireductor sp. PRIM-24 and Alteromonas sp. PRIM-21 showed 2.0% sulfate content. These bacterial EPS also showed antioxidant and emulsifying activities and the EPS produced by Enterobacter sp.PRIM-26 showed significantly higher antioxidant activities in terms of superoxide（IC50 0.33 mg·mL -1） and DPPH（IC50 0.44 mg·mL -1） radical scavenging. It also showed higher emulsifying activities against selected hydrophobic substrates with EI24 values above 60%. From the results of the study, it can be concluded that the isolated bacteria produce EPS that can be investigated in detail for biotechnological applications.展开更多
A yeast-like fungus strain B1 isolated from wild fungus Tremella aurantialba was identified and initially characterized. Two phylogenetic trees were generated based on the sequences of large subunit ribosomal RNA gene...A yeast-like fungus strain B1 isolated from wild fungus Tremella aurantialba was identified and initially characterized. Two phylogenetic trees were generated based on the sequences of large subunit ribosomal RNA gene D1/D2 regions and internal transcribed spacer (ITS) regions of related fungi, respectively. The analysis of D1/D2 regions and ITS sequences showed that fungus B1 was clustered together with T. aurantialba, T. aurantia and T. microspore in the phylogenetic trees. Both the morphological characteristic and phylogenetic analysis established that fungus B1 was one of the anamorph strains of T. aurantialba and belongs to Tremella genus. A fermentation medium for exopolysaccharides (EPS) production by T. aurantialba B1 . Plackett-Burmen design was used to evaluate the effects of different components in the culture medium. Glucose and yeast extract have significant influence on the EPS production. The concentrations of two factors were optimized subsequently using central composite design and response surface analysis. The results showed that 49.2 g/L glucose and 10.4 g/L yeast extract could lead to the maximum production of EPS (4.99 g/L). The optimized medium led to a 1.5-fold enhancement of the production of EPS by T. aurantialba B1 , as compared with that without optimization.展开更多
Lactobacillus delbrueckii subsp. bulgaricus, which has been widely used as a fermented milk starter, is a type of probiotic, and certain strains are able to produce exopolysaccharide (EPS). EPS produced from L. bulgar...Lactobacillus delbrueckii subsp. bulgaricus, which has been widely used as a fermented milk starter, is a type of probiotic, and certain strains are able to produce exopolysaccharide (EPS). EPS produced from L. bulgaricus contributes to the physical and biological function of dairy products by regulating immune response, and this tendency seems to place EPS with acidic groups. To date, six types of chemical structure have been determined and are basically composed from glucose (Glc), galactose (Gal), and rhamnose (Rha). Eps clusters on chromosome DNA control the EPS synthesis and are transcribed as one mRNA 14 genes with 18kb on L. bulgaricus Lfi5. Furthermore, L. bulgaricus is able to utilize lactose (Lac) as carbohydrate source, repeating units of EPS are synthesized from Glc 6-phosphate, generated by an Embden-Meyerhof (EM) pathway in cellular carbohydrate assimilation. This review discusses EPS produced from L. bulgaricus.展开更多
Baking of sourdough is a common practice and has the advantage of improving the nutritional value, sensory qualities and increasing the shelf life of the bread. This study therefore focus on the antimicrobial and anti...Baking of sourdough is a common practice and has the advantage of improving the nutritional value, sensory qualities and increasing the shelf life of the bread. This study therefore focus on the antimicrobial and antioxidant capacity of exopolysaccharides form Lactic Acid Bacteria (LAB) and its application in sourdough production. The Lactobacillus delbrueckii LDYG2 and Weissella confusa WCFF1 were collected from the culture collection Centre and the LABs were maintained in De Man, Rogosa and Sharpe (MRS) broth. Modified Exopolysaccharide Selection Medium (mESM) was used to produce the EPS while the total sugar concentration was determined using phenol-sulfuric acid method. The antibacterial, antioxidant, proximate, physical, organoleptic properties and the shelf life of the SDB produced were also evaluated. The quantity of EPS produced by LDYG2 and WCFF1 ranged from 4743.75 - 5090.03 g/L. Eight different sugars were present in both EPSLD and EPSWC with high antibacterial activity (24 mm and 23 mm) against B. cereus and S. aureus respectively. EPSLD and EPSWC had antioxidant capacity increased in a dose dependent (0.5 - 10 mg/mL) manner. EPSWCSDB had the highest proximate content except for moisture content. There was a significantly different (P ≤ 0.05) in the shelf life extension of the sourdough bread. WCEPSSDB was generally accepted in terms of colour, aroma, taste, texture and palatability. EPS produced by L. delbrueckii (EPSLD) and W. confusa (EPSWC) has antimicrobial and antioxidant capacity and can be used in production of nutraceutical sourdough bread with an improved shelf life and high consumer acceptability.展开更多
In the current study, in order to change the permeability of cell membrane and solve the problem of linked group of fungi mycelium, the method of adjusting osmotic pressure of medium and adding tween-80 was establishe...In the current study, in order to change the permeability of cell membrane and solve the problem of linked group of fungi mycelium, the method of adjusting osmotic pressure of medium and adding tween-80 was established. The utilized strain with relatively high exopolysaccharide (EPS) yield and low pigment level was obtained after the rejuvenation and sifting of long-preserved Aureobasidium pullulans strain. The optimal proportion of substrate was determined by means of orthogonal test. The transformation ratio of EPS was increased by 10% - 20% and the pigment content was greatly reduced. The fermenting liquor is between creamy white and pale yellow, and the white primary product can be gained without decolourization step. Furthermore, to magnify to 5 L bioreactor can get the similar result.展开更多
Exopolysaccharides(EPS)produced by endophytic fungi isolated from Cyclocarya paliurus have been reported to exhibit immunostimulatory activity in vitro;however,its in vivo immunoregulatory effects remain unclear.The s...Exopolysaccharides(EPS)produced by endophytic fungi isolated from Cyclocarya paliurus have been reported to exhibit immunostimulatory activity in vitro;however,its in vivo immunoregulatory effects remain unclear.The study aimed to investigate its protective effects and mechanisms against cyclophosphamide(CTX)-induced immunosuppression and intestinal injury in mice.EPS treatment mitigated body weight loss,thymic atrophy,and splenomegaly,while promoting intestinal repair by modulating cytokine secretion,T cell,goblet cell,MUC2,and tight junction proteins through activation of the Nrf2/HO-1 signaling pathway.Furthermore,gut microbiota and metabolomic analyses revealed that EPS ameliorated CTX-induced dysbiosis,corrected microbial translocation and niche imbalance,and restored lipid,bile acid,and amino acid metabolism.Collectively,these findings indicate that Penicillium-derived EPS can alleviate immunosuppression and intestinal injury by regulating gut microbiota composition,restoring intestinal barrier integrity,and re-establishing metabolic homeostasis.This study provides theoretical support for the potential application of fungal polysaccharides as immunomodulatory agents and functional food ingredients.展开更多
Sugar beet molasses,a sugar-rich byproduct of sugar beet industry,have great potential as a biorefinery feedstock for the production of value-added bio-products by microbial fermentation.The production of functional e...Sugar beet molasses,a sugar-rich byproduct of sugar beet industry,have great potential as a biorefinery feedstock for the production of value-added bio-products by microbial fermentation.The production of functional exopolysaccharides(EPS)by lactic acid bacteria(LAB)represents a promising strategy for valorizing sugar processing waste.This study screened and identified high-efficiency EPS-producing LAB isolates from beet juice.Among the 32 isolates,six LAB strains including Limosilactobacillus fermentum YL7,Lactiplantibacillus plantarum YL4,TC10,and CJ10,Leuconostoc mesenteroides TCT3 and TCT4,exhibited efficient bio-conversion of beet molasses to LAB-EPS,with yields varying from 13.96 to 22.26 g/L.Antioxidant activity analysis revealed that EPS from these strains displayed significant scavenging activities against ABTS^(+),DPPH,and-OH radicals.Notably,EPS produced by L.plantarum TC10 and L.fermentum YL7 exhibited superior ABTS+scavenging capacity,with rates up to 99.48% and 95.89% at 4 mg/mL,respectively.Additionally,EPS from strains YL4,YL7,TCT3 and TCT4 showed significant antibiofilm activity against S.aureus and E.coli,with EPS-YL7 inhibiting S.aureus biofilm formation by up to 90.49% at 8.0 mg/mL.Furthermore,EPS from strains TCT4 demonstrated great tolerance to digestive fluid compared to EPS from other strains,with a retention rate of 72% at the end of intestinal digestion.These findings suggest that EPS-producing LAB strains from beet juice can efficiently convert beet molasses into valuable EPS utilized as functional food ingredients.展开更多
Marine microbial-derived exopolysaccharides(EPS)have gradually gained popularity as function ingredients in the food industry because of their unique structures and various biological functions.EPS-LAN4 is a novel EPS...Marine microbial-derived exopolysaccharides(EPS)have gradually gained popularity as function ingredients in the food industry because of their unique structures and various biological functions.EPS-LAN4 is a novel EPS derived from the Limosilactobacillus fermentum LAN4,which is a derivative of marine lactobacilli.Its bacteria can stimulate the immune system,enhance the resistance of marine organisms to diseases,and reduce the risk of infection caused by pathogenic bacteria.In previous studies,it has been determined that EPS-LAN4 has a relatively small average molecular weight(13.52 kDa)and contains bothα-glycosidic andβ-glycosidic bonds,making it a highly water-soluble and bioavailable polysaccharide.In this study,it was demonstrated that EPS-LAN4 protects HUVECs from H_(2)O_(2)-induced effects by inhibiting the production of intracellular reactive oxy-gen species(ROS),blocking p53 mediated Caspase-3/-9 activation and activating the Keap1-Nrf2 pathway,thereby inhibiting cell apoptosis.In addition,during the activity research process,it was found that EPS not only has good antioxidant activity,but also excellent anti-angiogenic activity,and its synergistic effect is related to the structural characteristics of EPS.The results of this study provide new nutritional resources for the development of functional components for chronic metabolic disorders such as cardiovascular diseases,and also open up new avenues for research in the field of microbial polysaccharides.展开更多
Diabetes mellitus is a chronic metabolic disorder.Although natural components such as polyphenols and polysaccharides have demonstrated anti-diabetic potential,the in vivo synergistic effects of their combinations rem...Diabetes mellitus is a chronic metabolic disorder.Although natural components such as polyphenols and polysaccharides have demonstrated anti-diabetic potential,the in vivo synergistic effects of their combinations remain poorly understood.This study explored the hypoglycemic effects and molecular mechanisms of Bacillus subtilis exopolysaccharides(BS-EPS)and their combination with epigallocatechin gallate(EGCG)in type 2 diabetes mellitus(T2DM)mice.Monotherapy with BS-EPS(200 mg/kg⋅bw/day)or EGCG(100 mg/kg⋅bw/day)significantly reduced fasting blood glucose levels by 15.3%and 15.7%,respectively,while combination therapy showed a superior reduction of 25.4%.Moreover,the combined treatment significantly improved insulin sensitivity and alleviated hepatic injury.The combined treatment modulated the gut microbiota composition by enriching beneficial bacteria(including Faecalibaculum,Akkermansia,and Parabacteroides)while enhancing short-chain fatty acid production,particularly acetate.Metabolomic analysis revealed that the combined treatment altered bile acids and glycerophospholipids profiles,while modulating key metabolic pathways including choline metabolism,glycerophospholipid metabolism,and unsaturated fatty acid biosynthesis.These findings suggest that the combined intervention of BS-EPS and EGCG may synergistically ameliorate hyperglycemia through gut microbiota-metabolite-pathway interactions,supporting their potential as a dietary intervention for T2DM.展开更多
To explore the structure and stability properties of emulsion gel made by waxy maize starch(WMS)hydrogel incorporated with tea polyphenols(TPs)and exopolysaccharides(EPS).The structural properties(including microstruc...To explore the structure and stability properties of emulsion gel made by waxy maize starch(WMS)hydrogel incorporated with tea polyphenols(TPs)and exopolysaccharides(EPS).The structural properties(including microstructure),rheological properties,emulsifying properties,antioxidant properties and delivery function of emulsion gel were studied.The results demonstrated that the addition of TPs and EPS resulted in an increased pore size within the WMS hydrogel network,thereby enhancing its viscoelastic characteristics.Confocal laser scanning microscopy images revealed that varying concentrations of TPs led to distinct coating structures around oil droplets.Notably,the hydrogel containing 20%TPs exhibited an optimal encapsulation to oil droplets,contributing to a stable state for storage up to 30 days because of forming a uniform layer that effectively inhibited droplet aggregation.Moreover,WMS-TPs hydrogels supplemented with EPS showed significantly higher scavenging efficiency compared to those without EPS.Specifically,the WMS-20%TPs-EPS achieved a radical scavenging rate of 97.87±2.42%,surpassing other experimental groups.These findings indicate that WMS-TPs-EPS hydrogels can serve as effective food-grade matrix materials for stabilizing emulsion gel while enhancing their antioxidant properties,offering significant potential for the development of novel starch-based emulsion delivery systems in the food and pharmaceutical industries.展开更多
Enterobacter strains face limitations in scalable production.This study aimed to enhance fucose-containing exopolysaccharide(EPS)biosynthesis via UV mutagenesis and fermentation optimization.A high-yield mutant(Entero...Enterobacter strains face limitations in scalable production.This study aimed to enhance fucose-containing exopolysaccharide(EPS)biosynthesis via UV mutagenesis and fermentation optimization.A high-yield mutant(Enterobacter sp.915)was selected via UV irradiation,producing 55.93%higher EPS yield(0.368 g/L)compared to the wild type.Response surface methodology(RSM)was used to optimize medium components and culture conditions.The optimal parameters were maltose(194.71 g/L),malt extract(108.18 g/L),and shaking speed(160 rpm),which increased EPS production to 2.304 g/L,a 74%improvement.Structural analysis indicated the purified EPS(5.98 kDa)comprised fucose,galactose,glucose,and mannose in a ratio of 3.4:42.2:18.4:13,withα-glycosidic linkages and amorphous crystallinity.Thermal analysis showed stability up to 482.8℃,indicating the potential for industrial processing.The EPS also demonstrated significant moisture retention(81%RH:24 h absorption rate>50%)and antioxidant activities,including DPPH(34.33%),hydroxyl(48.1%),and ABTS+(50.27%)radical scavenging at 3.2 mg/mL.These properties were comparable to those of commercial fucosecontaining EPS,demonstrating its potential as a natural antioxidant and humectant in food applications.展开更多
Exopolysaccharides(EPS)derived from lactic acid bacteria have received considerable attention because of their diverse bioactivities and high safety.In our previous work,a crude EPS produced by Lactiplantibacillus pla...Exopolysaccharides(EPS)derived from lactic acid bacteria have received considerable attention because of their diverse bioactivities and high safety.In our previous work,a crude EPS produced by Lactiplantibacillus plantarum Z-1 under H2O2 stress and its three purified fractions were prepared and characterized.In the present work,antioxidant and anti-inflammatory activities of these EPSs were investigated.The four EPSs were found to possess considerable free radical scavenging activity,and be able to decrease the ROS and MDA levels in H_(2)O_(2)-induced oxidative stress RAW 264.7 macrophages,and increase the activities of SOD and CAT enzymes.It is likely that activating Nrf2/HO-1 signaling pathway is one of their important antioxidant mechanisms.These EPSs were also found to effectively reduce the secretion of inflammatory mediators,such as pro-inflammatory factors(TNF-α,IL-1β,IL6)and NO,and increase the release of anti-inflammatory factor IL-10.The anti-inflammatory effect of EPSs could be due to their ability to inhibit the activation of NF-κB/TLR4 signaling pathway and intracellular COX-2 signaling cascade.Therefore,these EPS fractions have good antioxidant and antiinflammatory activities,providing useful enlightenment for the application of these EPSs in functional foods and medicines.展开更多
Ulcerative colitis(UC)is a public health concern.The quest for drugs characterized by minimal side effects and optimal safety profiles for managing UC has emerged as a primary research topic.Recent evidence suggests t...Ulcerative colitis(UC)is a public health concern.The quest for drugs characterized by minimal side effects and optimal safety profiles for managing UC has emerged as a primary research topic.Recent evidence suggests the efficacy of Lactobacillus-derived exopolysaccharides containing mannose(MnEPSs)in alleviating UC.Lactoba-cillus could not synthesize MnEPSs in the glucose-only MRS medium,but with mannose added to the carbon source,MnEPSs were produced directionally,of which mannose accounts for 5.9-7.8%of the total sugar content.Subsequently,MnEPS-6M3,MnEPS-Q5M22,MnEPS-D4L1,and MnEPS-CCFM 1393 were used to investigate the mechanism of UC relief.The results showed that compared with non-MnEPSs,MnEPSs had the better effect on reliving UC.Phenotypically,four MnEPSs alleviated weight loss,DAI score,crypt disappearance,inflammatory cell infiltration,and mucosal edema of UC in mice.Mechanistically,MnEPSs increased the expression of ZO-1 by 52.38-115.87%to repair intestinal barrier,inhibited inflammatory factors(TNF-α,IL-1β,IL-6,IFN-γand IL-17)and increasd anti-inflammatory cytokines(IL-10)by reducing colonic F4/80^(+)macrophages(decreased 4.34-7.01%)and colonic iNOS^(+)M1 macrophages(decreased 7.3-10.52%),and promoted the production of acetic acid(increased 153.21-226.93%),propionic acid(increased 360.71-528.57%),and butyric acid(increased 127.45-156.86%)in cecal contents.Interestingly,MnEPS-Q5M22 and MnEPS-CCFM 1393 increased the abundance of butyric acid-producing Dunaliella.In summary,this study provides a theoretical basis for the directional synthesis of functional MnEPSs.展开更多
Carbon source is an essential factor influencing exopolysaccharide(EPS)production.However,there is still lack of systematic investigation how carbon sources affect EPS characterization in S.thermophilus.In this study,...Carbon source is an essential factor influencing exopolysaccharide(EPS)production.However,there is still lack of systematic investigation how carbon sources affect EPS characterization in S.thermophilus.In this study,EPSs from S.thermophilus S-3 using lactose,glucose and galactose as the sole carbon source were characterized,and named LacS3EPS,GlcS3EPS and GalS3EPS,respectively.The yield of EPSs was significantly affected by the carbon source.The monosaccharide and linkage type of EPSs were independent of the carbon source.Compared with LacS3EPS,the glucose content of GlcS3EPS increased while galactose content decreased,but the opposite trend occurred for GalS3EPS.The molecular weight of EPSs changed significantly,with the highest for GlcS3EPS(1630 kDa)and the lowest for GalS3EPS(414 kDa).Combined with two wormlike cylinder models,the conformation of EPSs was characterized by random coils with descending rigidity in the order GlcS3EPS>LacS3EPS>GalS3EPS.Additionally,gene transcription and correlation analysis revealed that the variation in EPSs was mainly related to the genes encoding nucleotide sugars and glycosyltransferases.The results suggested that carbon sources could alter molecular characteristics of EPS by influencing gene expression related to EPS biosynthesis.展开更多
Exopolysaccharides(EPS)produced by lactic acid bacteria(LAB)are high-molecular-weight carbohydrate polymers.They play a crucial role in improving the rheological properties,texture,viscosity,and colloidal stability of...Exopolysaccharides(EPS)produced by lactic acid bacteria(LAB)are high-molecular-weight carbohydrate polymers.They play a crucial role in improving the rheological properties,texture,viscosity,and colloidal stability of fermented foods.Beyond their technological functions,LAB EPS also exhibit diverse bioactivities,including modulation of the gut microbiota and host immune responses,as well as antioxidant,antiinflammatory,and anticancer effects.This review summarizes recent advances in LAB EPS reported between 2020 and 2025,with a particular focus on four key aspects:biosynthesis,strain development,structural features,and anticancer activity.It also highlights recent progress in their industrial applications,while emphasizing the current understanding of the anticancer potential of LAB EPS and their prospects for practical application.展开更多
基金funded by the Key Research and Development Project of Zhejiang Province(2020C02034)。
文摘In vitro simulated colonic fermentation studies have shown the prebiotic potential of exopolysaccharides from Lactiplantibacillus plantarum YY-112(YEPS).Its immunomodulatory effects and related mechanisms were systematically investigated in this study.We observed that YEPS intervene in immune responses and improve intestinal microbial structure in normal mice,including significantly increasing the relative abundance of Enterorhabdus and norank_f_norank_o_Clostridia UCG-014 as well as decreasing that of unclassified_c_Bacilli(P<0.05).In the immunocompromised mouse model,YEPS decreased interleukin-6 levels(P<0.05)and protected the spleen by regulating lymphocyte levels.YEPS preserved the intestinal barrier by improving Mucin 2,Zonula occludens protein 1,and Occludin expression.Moreover,YEPS significantly reduced the relative abundance of Bacillus,unclassified_c_Bacilli,Lachnoclostridium,Eubacterium_xylanophilum_group,and Desulfovibrio(P<0.05),potentially enhancing mice immunity by improving the intestinal microbiota associated with immune function.In conclusion,YEPS can be used as a natural functional extract with prebiotic effects that may improve host immunity.This provided the basis for the application of YEPS as a novel potential food additive.
基金supported by the Natural Science Foundation of Heilongjiang Province(LH2021C075)Basic Research Business Expenses and Research Projects of Provincial Higher Education Institutions in Heilongjiang Province(2022-KYYWF-1077).
文摘Lactic acid bacteria(LAB)exopolysaccharides(EPS)reveal high safety and multiple activities,and are typical postbiotics produced by LAB during fermentation.In this paper,6583 articles on LAB-EPS from Web of Science and Elsevier databases were retrieved,and 236 articles related to this review were screened.The EPS from 90 LAB strains were summarized in terms of their extraction methods,yield,molecular weight,monosaccharide composition,glycosidic bond configuration and the structural and activity relationships(SARs).However,there exist great challenges as for the low yield and high cost in EPS production.Therefore,this review further elaborated the mechanism of EPS secretion,the anabolic pathway of EPS,the structure and mechanism of key enzymes involving in EPS synthesis process,the prospect of gene regulation for EPS secretion,and proposed the engineering strategies for increasing EPS yield or tailored EPS design in recent years.In addition,CRISPR/Cas9 gene editing technology was also discussed in the production control of EPS in LAB.Finally,the engineering strategy of increasing EPS yield in recent years was proposed.This work might provide important theoretical support for the production and application of LAB-based EPS.
基金the Natural Science Foundation of Shandong Province(No.Z2003D01).
文摘Microbial polysaccharides represent a class of important products of growing interest for many sectors of indus- try. In recent years, there has been a growing interest in isolating new exopolysaccharides (EPSs)-producing bacteria from marine environments, particularly from various extreme marine environments. Many new marine microbial EPSs with novel chemical compositions, properties and structures have been found to have potential applications in fields such as adhesives, textiles, Pharmaceuticals and medicine for anti-cancer, food additives, oil recovery and metal removal in mining and indus- trial waste treatments, etc This paper gives a brief summary of the information about the EPSs produced by marine bacteria, including their chemical compositions, properties and structures, together with their potential applications in industry.
基金supported by the National Natural Science Foundation of China(32030101,32272914)the National Key R&D Program of China(2022YFD1300700)the Heilongjiang Touyan Innovation Team Program。
文摘Background Salmonella typhimurium(S.T),as an important foodborne bacterial pathogen,can cause diarrhea and gastroenteritis in humans and animals.Numerous studies have confirmed that exopolysaccharides(EPSs)have various biological functions,but the mechanism through which EPSs improve the immunity of animals against the invasion of pathogenic bacteria is unclear.Here,we explored the protective effect of EPSs of Lactobacillus rhamnosus GG(LGG)on the S.T-infected intestine.Methods Mice received adequate food and drinking water for one week before the start of the experiment.After 7 d of prefeeding,2×108 CFU/mL S.T solution and an equivalent volume of saline(control group)were given orally for 1 d.On the fourth day,the mice were treated with 0.5 mg/mL EPSs,1.0 mg/mL EPSs,2.0 mg/mL EPSs,or 2.0 mg/mL penicillin for 7 d.Finally,the body and relative organ weight,histological staining,and the levels of antioxidant enzyme activity and inflammatory cytokines were determined.Results The S.T-infected mice exhibited symptoms of decreased appetite,somnolence,diarrhea and flagging spirit.Treatment with EPSs and penicillin improved the weight loss of the mice,and the high dose of EPSs showed the best therapeutic effect.EPSs significantly ameliorated S.T-induced ileal injury in mice.High-dose EPSs were more effective than penicillin for alleviating ileal oxidative damage induced by S.T.The mRNA levels of inflammatory cytokines in the ileum of mice showed that the regulatory effects of EPSs on inflammatory cytokines were better than those of penicillin.EPSs could inhibit the expression and activation of key proteins of the TLR4/NF-κB/MAPK pathway and thereby suppress the level of S.T-induced ileal inflammation.Conclusions EPSs attenuate S.T-induced immune responses by inhibiting the expression of key proteins in the TLR4/NF-κB/MAPK signaling pathway.Moreover,EPSs could promote bacterial aggregation into clusters,which may be a potential strategy for reducing the bacterial invasion of intestinal epithelial cells.
文摘<span style="line-height:1.5;"><span style="font-family:Verdana;">An antioxidant is a substance that inhibits the oxidation of other molecules caused by free radicals. The inbuilt antioxidant systems possessed by living or</span><span style="font-family:Verdana;">g</span><span style="font-family:Verdana;">anisms are generally not enough to prevent them from oxidati</span><span style="font-family:Verdana;">ve damage</span><span style="font-family:Verdana;">s and the use</span></span><span style="line-height:1.5;font-family:Verdana;">s</span><span style="line-height:1.5;font-family:Verdana;"> of synthetic antioxidants also ha</span><span style="line-height:1.5;font-family:Verdana;">ve</span><span style="line-height:1.5;font-family:Verdana;"> some harmful effects. T</span><span style="line-height:1.5;"><span style="font-family:Verdana;">his study was aimed at evaluating the antioxidant activities of exopolysaccharides p</span><span style="font-family:Verdana;">roduced by lactic acid bacteria isolated from yoghurt. Lactic acid bac</span><span style="font-family:Verdana;">teria (LAB) were isolated from six different brands of commercially available yoghurt using deMan Rogosa Sharpe (MRS) agar. The LAB isolates were identified based on morphological and biochemical analyses and were screened for exopolysaccharide (EPS) production. The LAB isolates screened positive were used for EPS production in a liquid medium and the EPS produced were purified and quantified using standard methods. Antioxidant activities of the E</span><span style="font-family:Verdana;">PS were evaluated by determining the 1,1-dip</span><span style="font-family:Verdana;">henyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, ferric ion reducing power, and total phenolic contents. Data obtained were analysed using Analysis of Variance. Total lactic acid bacterial count obtained from the yoghurt samples ranged from 0 - 3.9 × 10</span><sup><span style="font-family:Verdana;">4</span></sup><span style="font-family:Verdana;"> CFU/mL with sample A (Fan Yoghurt) having the highest LAB count (3.9 × 10</span><sup><span style="font-family:Verdana;">4</span></sup><span style="font-family:Verdana;"> CFU/mL). The isolated LAB and their incidence rate were </span><i><span style="font-family:Verdana;">Lactobacillus plantarum </span></i><span style="font-family:Verdana;">(25.49%),</span><i><span style="font-family:Verdana;"> L. delbrueckii </span></i><span style="font-family:Verdana;">(19.61%),</span><i><span style="font-family:Verdana;"> L. fermentum </span></i><span style="font-family:Verdana;">(15.69%),</span><i><span style="font-family:Verdana;"> L. acidophilus </span></i><span style="font-family:Verdana;">(13.73%), </span><i><span style="font-family:Verdana;">Leuconostoc mesenteroides </span></i><span style="font-family:Verdana;">(11.76%),</span><i><span style="font-family:Verdana;"> Lactococcus lactis </span></i><span style="font-family:Verdana;">(7.84%), and </span><i><span style="font-family:Verdana;">Lactobacillus casei </span></i><span style="font-family:Verdana;">(5.88%). Fifty-one out of the 64 LAB isolates were screened positive for EPS production and only six were able to produce substantial quantity of EPS ranging from 127.4 - 208.5 mg/L. The exopolysaccharides produced by </span><i><span style="font-family:Verdana;">L. fermentum</span></i><span style="font-family:Verdana;"> had the highest DPPH radical scavenging activity (62.90%) while that of </span><i><span style="font-family:Verdana;">L. plantarum</span></i><span style="font-family:Verdana;"> had the lowest (23.10%) at a concentration of 1000 μg/mL. Also, the EPS produced by </span><i><span style="font-family:Verdana;">L. fermentum</span></i><span style="font-family:Verdana;"> recorded the highest ferric ion reducing power (12.89 mg AAE/mL) at 1000 μg/mL while that of </span><i><span style="font-family:Verdana;">L. plantarum</span></i><span style="font-family:Verdana;"> had the lowest (5.62 mg AAE/mL). At 1000 μg/mL, the total phenolic contents of the EPS samples ranged from 1.41 - 1.58 mg GAE/mL, and the EPS produced by </span><i><span style="font-family:Verdana;">L. fermentum </span></i><span style="font-family:Verdana;">had the highest (1.58 mg GAE/mL) while those produced by </span><i><span style="font-family:Verdana;">L. paracasei </span></i><span style="font-family:Verdana;">had the lowest (1.41 mg GAE/mL). This study revealed that the exopolysaccharides produced by the LAB isolates showed high antioxidant activities with respect to their DPPH free radical scavenging activity, ferric ion reducing power and total phenolic contents.
基金financially supported by the India and author Priyanka P acknowledges the Yenepoya University Junior research fellowshipBRNS(2013/34/19/BRNS/1210)
文摘In this study, bacteria associated with marine organisms were screened for the production of exopolysaccharides（EPSs） on MY media containing sea salts（2.5%-10%）. Three selected isolates were identified as Alteromonas sp. PRIM-21, Nitratireductor sp. PRIM-24 and Enterobacter sp. PRIM-26 using 16 S r RNA gene sequencing. Optimization of the growth and EPS production kinetics in relation to incubation time were assessed. The purified EPS yield was 590, 650 and 540 mg·L-1 culture media respectively in Alteromonas sp. PRIM-21, Nitratireductor sp. PRIM-24 and Enterobacter sp. PRIM-26. Biochemical and FTIR analyses revealed the presence of biologically important functional groups in the EPS produced by all the three isolates. The EPS produced by Nitratireductor sp. PRIM-24 and Alteromonas sp. PRIM-21 showed 2.0% sulfate content. These bacterial EPS also showed antioxidant and emulsifying activities and the EPS produced by Enterobacter sp.PRIM-26 showed significantly higher antioxidant activities in terms of superoxide（IC50 0.33 mg·mL -1） and DPPH（IC50 0.44 mg·mL -1） radical scavenging. It also showed higher emulsifying activities against selected hydrophobic substrates with EI24 values above 60%. From the results of the study, it can be concluded that the isolated bacteria produce EPS that can be investigated in detail for biotechnological applications.
基金Supported by the Key Project of National 9th Five-Year Plan Program (No.96-C02-03-06)
文摘A yeast-like fungus strain B1 isolated from wild fungus Tremella aurantialba was identified and initially characterized. Two phylogenetic trees were generated based on the sequences of large subunit ribosomal RNA gene D1/D2 regions and internal transcribed spacer (ITS) regions of related fungi, respectively. The analysis of D1/D2 regions and ITS sequences showed that fungus B1 was clustered together with T. aurantialba, T. aurantia and T. microspore in the phylogenetic trees. Both the morphological characteristic and phylogenetic analysis established that fungus B1 was one of the anamorph strains of T. aurantialba and belongs to Tremella genus. A fermentation medium for exopolysaccharides (EPS) production by T. aurantialba B1 . Plackett-Burmen design was used to evaluate the effects of different components in the culture medium. Glucose and yeast extract have significant influence on the EPS production. The concentrations of two factors were optimized subsequently using central composite design and response surface analysis. The results showed that 49.2 g/L glucose and 10.4 g/L yeast extract could lead to the maximum production of EPS (4.99 g/L). The optimized medium led to a 1.5-fold enhancement of the production of EPS by T. aurantialba B1 , as compared with that without optimization.
文摘Lactobacillus delbrueckii subsp. bulgaricus, which has been widely used as a fermented milk starter, is a type of probiotic, and certain strains are able to produce exopolysaccharide (EPS). EPS produced from L. bulgaricus contributes to the physical and biological function of dairy products by regulating immune response, and this tendency seems to place EPS with acidic groups. To date, six types of chemical structure have been determined and are basically composed from glucose (Glc), galactose (Gal), and rhamnose (Rha). Eps clusters on chromosome DNA control the EPS synthesis and are transcribed as one mRNA 14 genes with 18kb on L. bulgaricus Lfi5. Furthermore, L. bulgaricus is able to utilize lactose (Lac) as carbohydrate source, repeating units of EPS are synthesized from Glc 6-phosphate, generated by an Embden-Meyerhof (EM) pathway in cellular carbohydrate assimilation. This review discusses EPS produced from L. bulgaricus.
文摘Baking of sourdough is a common practice and has the advantage of improving the nutritional value, sensory qualities and increasing the shelf life of the bread. This study therefore focus on the antimicrobial and antioxidant capacity of exopolysaccharides form Lactic Acid Bacteria (LAB) and its application in sourdough production. The Lactobacillus delbrueckii LDYG2 and Weissella confusa WCFF1 were collected from the culture collection Centre and the LABs were maintained in De Man, Rogosa and Sharpe (MRS) broth. Modified Exopolysaccharide Selection Medium (mESM) was used to produce the EPS while the total sugar concentration was determined using phenol-sulfuric acid method. The antibacterial, antioxidant, proximate, physical, organoleptic properties and the shelf life of the SDB produced were also evaluated. The quantity of EPS produced by LDYG2 and WCFF1 ranged from 4743.75 - 5090.03 g/L. Eight different sugars were present in both EPSLD and EPSWC with high antibacterial activity (24 mm and 23 mm) against B. cereus and S. aureus respectively. EPSLD and EPSWC had antioxidant capacity increased in a dose dependent (0.5 - 10 mg/mL) manner. EPSWCSDB had the highest proximate content except for moisture content. There was a significantly different (P ≤ 0.05) in the shelf life extension of the sourdough bread. WCEPSSDB was generally accepted in terms of colour, aroma, taste, texture and palatability. EPS produced by L. delbrueckii (EPSLD) and W. confusa (EPSWC) has antimicrobial and antioxidant capacity and can be used in production of nutraceutical sourdough bread with an improved shelf life and high consumer acceptability.
文摘In the current study, in order to change the permeability of cell membrane and solve the problem of linked group of fungi mycelium, the method of adjusting osmotic pressure of medium and adding tween-80 was established. The utilized strain with relatively high exopolysaccharide (EPS) yield and low pigment level was obtained after the rejuvenation and sifting of long-preserved Aureobasidium pullulans strain. The optimal proportion of substrate was determined by means of orthogonal test. The transformation ratio of EPS was increased by 10% - 20% and the pigment content was greatly reduced. The fermenting liquor is between creamy white and pale yellow, and the white primary product can be gained without decolourization step. Furthermore, to magnify to 5 L bioreactor can get the similar result.
基金supported by the Research Project of the State Key Laboratory of Food Science and Resources,Nanchang University(No.SKLF-ZZB-202521)the Jiangxi Province Postgraduate Innovation Foundation(No.YC2025-B031).
文摘Exopolysaccharides(EPS)produced by endophytic fungi isolated from Cyclocarya paliurus have been reported to exhibit immunostimulatory activity in vitro;however,its in vivo immunoregulatory effects remain unclear.The study aimed to investigate its protective effects and mechanisms against cyclophosphamide(CTX)-induced immunosuppression and intestinal injury in mice.EPS treatment mitigated body weight loss,thymic atrophy,and splenomegaly,while promoting intestinal repair by modulating cytokine secretion,T cell,goblet cell,MUC2,and tight junction proteins through activation of the Nrf2/HO-1 signaling pathway.Furthermore,gut microbiota and metabolomic analyses revealed that EPS ameliorated CTX-induced dysbiosis,corrected microbial translocation and niche imbalance,and restored lipid,bile acid,and amino acid metabolism.Collectively,these findings indicate that Penicillium-derived EPS can alleviate immunosuppression and intestinal injury by regulating gut microbiota composition,restoring intestinal barrier integrity,and re-establishing metabolic homeostasis.This study provides theoretical support for the potential application of fungal polysaccharides as immunomodulatory agents and functional food ingredients.
基金supported by Bofeng Talent Plan Project of Xinjiang Changji Hui Autonomous Prefecture,China(2021015)Students’Research Interesting Training Support by Sichuan Agricultural University,China(2023243).
文摘Sugar beet molasses,a sugar-rich byproduct of sugar beet industry,have great potential as a biorefinery feedstock for the production of value-added bio-products by microbial fermentation.The production of functional exopolysaccharides(EPS)by lactic acid bacteria(LAB)represents a promising strategy for valorizing sugar processing waste.This study screened and identified high-efficiency EPS-producing LAB isolates from beet juice.Among the 32 isolates,six LAB strains including Limosilactobacillus fermentum YL7,Lactiplantibacillus plantarum YL4,TC10,and CJ10,Leuconostoc mesenteroides TCT3 and TCT4,exhibited efficient bio-conversion of beet molasses to LAB-EPS,with yields varying from 13.96 to 22.26 g/L.Antioxidant activity analysis revealed that EPS from these strains displayed significant scavenging activities against ABTS^(+),DPPH,and-OH radicals.Notably,EPS produced by L.plantarum TC10 and L.fermentum YL7 exhibited superior ABTS+scavenging capacity,with rates up to 99.48% and 95.89% at 4 mg/mL,respectively.Additionally,EPS from strains YL4,YL7,TCT3 and TCT4 showed significant antibiofilm activity against S.aureus and E.coli,with EPS-YL7 inhibiting S.aureus biofilm formation by up to 90.49% at 8.0 mg/mL.Furthermore,EPS from strains TCT4 demonstrated great tolerance to digestive fluid compared to EPS from other strains,with a retention rate of 72% at the end of intestinal digestion.These findings suggest that EPS-producing LAB strains from beet juice can efficiently convert beet molasses into valuable EPS utilized as functional food ingredients.
基金supported by the Guangdong Basic and Applied Basic Research Foundation(2023A1515010005)Special funds for universities in Guangdong Province in the key areas of biomedicine and health(2023ZDZX2025)the Innovative Team Program of High Education of Guangdong Province(2021KCXTD021).
文摘Marine microbial-derived exopolysaccharides(EPS)have gradually gained popularity as function ingredients in the food industry because of their unique structures and various biological functions.EPS-LAN4 is a novel EPS derived from the Limosilactobacillus fermentum LAN4,which is a derivative of marine lactobacilli.Its bacteria can stimulate the immune system,enhance the resistance of marine organisms to diseases,and reduce the risk of infection caused by pathogenic bacteria.In previous studies,it has been determined that EPS-LAN4 has a relatively small average molecular weight(13.52 kDa)and contains bothα-glycosidic andβ-glycosidic bonds,making it a highly water-soluble and bioavailable polysaccharide.In this study,it was demonstrated that EPS-LAN4 protects HUVECs from H_(2)O_(2)-induced effects by inhibiting the production of intracellular reactive oxy-gen species(ROS),blocking p53 mediated Caspase-3/-9 activation and activating the Keap1-Nrf2 pathway,thereby inhibiting cell apoptosis.In addition,during the activity research process,it was found that EPS not only has good antioxidant activity,but also excellent anti-angiogenic activity,and its synergistic effect is related to the structural characteristics of EPS.The results of this study provide new nutritional resources for the development of functional components for chronic metabolic disorders such as cardiovascular diseases,and also open up new avenues for research in the field of microbial polysaccharides.
基金financially supported by the National Key R&D Program of China(2022YFF1100600/2022YFF1100605)the Science and Technology Support Program(Modern Agriculture)of Jiangsu Province(BE2022323)the Fundamental Research Funds for the Cornell University(No.JUSRP202504003).
文摘Diabetes mellitus is a chronic metabolic disorder.Although natural components such as polyphenols and polysaccharides have demonstrated anti-diabetic potential,the in vivo synergistic effects of their combinations remain poorly understood.This study explored the hypoglycemic effects and molecular mechanisms of Bacillus subtilis exopolysaccharides(BS-EPS)and their combination with epigallocatechin gallate(EGCG)in type 2 diabetes mellitus(T2DM)mice.Monotherapy with BS-EPS(200 mg/kg⋅bw/day)or EGCG(100 mg/kg⋅bw/day)significantly reduced fasting blood glucose levels by 15.3%and 15.7%,respectively,while combination therapy showed a superior reduction of 25.4%.Moreover,the combined treatment significantly improved insulin sensitivity and alleviated hepatic injury.The combined treatment modulated the gut microbiota composition by enriching beneficial bacteria(including Faecalibaculum,Akkermansia,and Parabacteroides)while enhancing short-chain fatty acid production,particularly acetate.Metabolomic analysis revealed that the combined treatment altered bile acids and glycerophospholipids profiles,while modulating key metabolic pathways including choline metabolism,glycerophospholipid metabolism,and unsaturated fatty acid biosynthesis.These findings suggest that the combined intervention of BS-EPS and EGCG may synergistically ameliorate hyperglycemia through gut microbiota-metabolite-pathway interactions,supporting their potential as a dietary intervention for T2DM.
基金supported by the Basic Research Project of Free Exploration,Science and Technology Department of Jilin Province,China(YDZJ202201ZYTS688).
文摘To explore the structure and stability properties of emulsion gel made by waxy maize starch(WMS)hydrogel incorporated with tea polyphenols(TPs)and exopolysaccharides(EPS).The structural properties(including microstructure),rheological properties,emulsifying properties,antioxidant properties and delivery function of emulsion gel were studied.The results demonstrated that the addition of TPs and EPS resulted in an increased pore size within the WMS hydrogel network,thereby enhancing its viscoelastic characteristics.Confocal laser scanning microscopy images revealed that varying concentrations of TPs led to distinct coating structures around oil droplets.Notably,the hydrogel containing 20%TPs exhibited an optimal encapsulation to oil droplets,contributing to a stable state for storage up to 30 days because of forming a uniform layer that effectively inhibited droplet aggregation.Moreover,WMS-TPs hydrogels supplemented with EPS showed significantly higher scavenging efficiency compared to those without EPS.Specifically,the WMS-20%TPs-EPS achieved a radical scavenging rate of 97.87±2.42%,surpassing other experimental groups.These findings indicate that WMS-TPs-EPS hydrogels can serve as effective food-grade matrix materials for stabilizing emulsion gel while enhancing their antioxidant properties,offering significant potential for the development of novel starch-based emulsion delivery systems in the food and pharmaceutical industries.
基金supported by the Natural Science Foundation of Sichuan Province(2022NSFSC1634)the Key Projects of Chengdu Institute of Biology,Chinese Academy of Sciences(QYJC 2024-3).
文摘Enterobacter strains face limitations in scalable production.This study aimed to enhance fucose-containing exopolysaccharide(EPS)biosynthesis via UV mutagenesis and fermentation optimization.A high-yield mutant(Enterobacter sp.915)was selected via UV irradiation,producing 55.93%higher EPS yield(0.368 g/L)compared to the wild type.Response surface methodology(RSM)was used to optimize medium components and culture conditions.The optimal parameters were maltose(194.71 g/L),malt extract(108.18 g/L),and shaking speed(160 rpm),which increased EPS production to 2.304 g/L,a 74%improvement.Structural analysis indicated the purified EPS(5.98 kDa)comprised fucose,galactose,glucose,and mannose in a ratio of 3.4:42.2:18.4:13,withα-glycosidic linkages and amorphous crystallinity.Thermal analysis showed stability up to 482.8℃,indicating the potential for industrial processing.The EPS also demonstrated significant moisture retention(81%RH:24 h absorption rate>50%)and antioxidant activities,including DPPH(34.33%),hydroxyl(48.1%),and ABTS+(50.27%)radical scavenging at 3.2 mg/mL.These properties were comparable to those of commercial fucosecontaining EPS,demonstrating its potential as a natural antioxidant and humectant in food applications.
基金supported by“Pioneer”and“Leading Goose”R&D Program of Zhejiang of China(2022C02012).
文摘Exopolysaccharides(EPS)derived from lactic acid bacteria have received considerable attention because of their diverse bioactivities and high safety.In our previous work,a crude EPS produced by Lactiplantibacillus plantarum Z-1 under H2O2 stress and its three purified fractions were prepared and characterized.In the present work,antioxidant and anti-inflammatory activities of these EPSs were investigated.The four EPSs were found to possess considerable free radical scavenging activity,and be able to decrease the ROS and MDA levels in H_(2)O_(2)-induced oxidative stress RAW 264.7 macrophages,and increase the activities of SOD and CAT enzymes.It is likely that activating Nrf2/HO-1 signaling pathway is one of their important antioxidant mechanisms.These EPSs were also found to effectively reduce the secretion of inflammatory mediators,such as pro-inflammatory factors(TNF-α,IL-1β,IL6)and NO,and increase the release of anti-inflammatory factor IL-10.The anti-inflammatory effect of EPSs could be due to their ability to inhibit the activation of NF-κB/TLR4 signaling pathway and intracellular COX-2 signaling cascade.Therefore,these EPS fractions have good antioxidant and antiinflammatory activities,providing useful enlightenment for the application of these EPSs in functional foods and medicines.
基金supported by the National Key Research and Development Program of China(NO.2022YFF1100203).
文摘Ulcerative colitis(UC)is a public health concern.The quest for drugs characterized by minimal side effects and optimal safety profiles for managing UC has emerged as a primary research topic.Recent evidence suggests the efficacy of Lactobacillus-derived exopolysaccharides containing mannose(MnEPSs)in alleviating UC.Lactoba-cillus could not synthesize MnEPSs in the glucose-only MRS medium,but with mannose added to the carbon source,MnEPSs were produced directionally,of which mannose accounts for 5.9-7.8%of the total sugar content.Subsequently,MnEPS-6M3,MnEPS-Q5M22,MnEPS-D4L1,and MnEPS-CCFM 1393 were used to investigate the mechanism of UC relief.The results showed that compared with non-MnEPSs,MnEPSs had the better effect on reliving UC.Phenotypically,four MnEPSs alleviated weight loss,DAI score,crypt disappearance,inflammatory cell infiltration,and mucosal edema of UC in mice.Mechanistically,MnEPSs increased the expression of ZO-1 by 52.38-115.87%to repair intestinal barrier,inhibited inflammatory factors(TNF-α,IL-1β,IL-6,IFN-γand IL-17)and increasd anti-inflammatory cytokines(IL-10)by reducing colonic F4/80^(+)macrophages(decreased 4.34-7.01%)and colonic iNOS^(+)M1 macrophages(decreased 7.3-10.52%),and promoted the production of acetic acid(increased 153.21-226.93%),propionic acid(increased 360.71-528.57%),and butyric acid(increased 127.45-156.86%)in cecal contents.Interestingly,MnEPS-Q5M22 and MnEPS-CCFM 1393 increased the abundance of butyric acid-producing Dunaliella.In summary,this study provides a theoretical basis for the directional synthesis of functional MnEPSs.
基金supported by National Natural Science Foundation of China(grants No.32101928,and 32272300)National Science Fund for Distinguished Young Scholars(grant No.32025029)+2 种基金Natural Science Foundation of Shanghai(grant No.22ZR1444000)the CIFST-Yakult Foundation of Intestinal Health and Probiotics for Young Scientists(grant No.2023-Y03)Shanghai Engineering Research Center of Food Microbiology(grant No.19DZ2281100).
文摘Carbon source is an essential factor influencing exopolysaccharide(EPS)production.However,there is still lack of systematic investigation how carbon sources affect EPS characterization in S.thermophilus.In this study,EPSs from S.thermophilus S-3 using lactose,glucose and galactose as the sole carbon source were characterized,and named LacS3EPS,GlcS3EPS and GalS3EPS,respectively.The yield of EPSs was significantly affected by the carbon source.The monosaccharide and linkage type of EPSs were independent of the carbon source.Compared with LacS3EPS,the glucose content of GlcS3EPS increased while galactose content decreased,but the opposite trend occurred for GalS3EPS.The molecular weight of EPSs changed significantly,with the highest for GlcS3EPS(1630 kDa)and the lowest for GalS3EPS(414 kDa).Combined with two wormlike cylinder models,the conformation of EPSs was characterized by random coils with descending rigidity in the order GlcS3EPS>LacS3EPS>GalS3EPS.Additionally,gene transcription and correlation analysis revealed that the variation in EPSs was mainly related to the genes encoding nucleotide sugars and glycosyltransferases.The results suggested that carbon sources could alter molecular characteristics of EPS by influencing gene expression related to EPS biosynthesis.
基金supported by the project of National Key R&D Pro-gram of China(No.2021YFA0910800)the Key Technologies R&D Program of Guangdong Province(No.232021072010200004)Shenzhen Science and Technology Program:Shenzhen Key Laboratory of Food Macromolecules Science and Processing(No.ZDSYS20210623100800001).
文摘Exopolysaccharides(EPS)produced by lactic acid bacteria(LAB)are high-molecular-weight carbohydrate polymers.They play a crucial role in improving the rheological properties,texture,viscosity,and colloidal stability of fermented foods.Beyond their technological functions,LAB EPS also exhibit diverse bioactivities,including modulation of the gut microbiota and host immune responses,as well as antioxidant,antiinflammatory,and anticancer effects.This review summarizes recent advances in LAB EPS reported between 2020 and 2025,with a particular focus on four key aspects:biosynthesis,strain development,structural features,and anticancer activity.It also highlights recent progress in their industrial applications,while emphasizing the current understanding of the anticancer potential of LAB EPS and their prospects for practical application.
