DEAE-Sepharose Fast Flow Research Articles

Structural characterization of a galacturonic acid-rich polysaccharide from Ziziphus Jujuba cv. Muzao

Jujube (Zizyphus jujuba Mill.) have been widely used as a health food and medicinal herb in oriental medicine. In the present study, a novel galacturonic acid-rich polysaccharide (PZMP3-2) was isolated from Zizyphus Jujuba cv. Muzao through hot water extraction, ethanol precipitation, and purification with DEAE-Sepharose Fast Flow and Sephacryl S-300 column chromatography. The chemical structures of PZMP3-2 were elucidated by methylation analysis, along with HPGPC, FT-IR spectroscopy, GC-MS, 1D NMR spectroscopy, and 2D NMR spectroscopy. Its morphological properties were further characterized by SEM, AFM, and XRD. Monosaccharide compositional analysis of PZMP3-2 revealed the presence of rhamnose, arabinose, galactose, and galacturonic acid at a molar ratio of 1.74:2.00: 1.00:18.69, and the HPGPC data demonstrated an average molecular weight of 58.21 kDa. Structural and linkage analysis by GC-MS and NMR spectroscopy suggested that PZMP3-2 was a homogalacturonan (HG)-like pectic polysaccharide branched at C-2 with some Araf and Rhap residues. Such unique structure of PZMP3-2 may indicate distinct bioactivities and further application in food and even clinic.

Purification of R-phycoerythrin from a marine macroalga Gracilaria gracilis by anion-exchange chromatography

Gracilaria gracilis, a red macroalga, represents an exploited important biomass. One of the potential uses of this red seaweed is the production of valuable molecules such as R-phycoerythrin. This compound has recently found applications in food and cosmetic industries as a natural colorant, in conducting medical diagnosis and in biology. However, after R-phycoerythrin extraction the protein extract has to be concentrated and pre-purified, which is commonly expensive and requires many steps. In this paper, R-phycoerythrin from the crude extract obtained by phosphate buffer 20 mM, pH 7.1, was purified by one-step chromatographic method. Native R-phycoerythrin was achieved with a high purity index (A565/A280 ratio) of 3.25 (3.2 = standard R-phycoerythrin purity) after purification on DEAE Sepharose fast flow chromatography with the obtained fraction at 200 mM NaCl. This fraction presented the absorption and emission spectra of R-phycoerythrin with major absorbance at 498, 540, and 565 nm. Native form of this molecule was presented about 260 kDa. Besides, the purified pigment R-phycoerythrin included four subunits: α subunit (18 kDa), β subunit (21 kDa), γ subunit (29 kDa), and γ’ subunit (27 kDa) by gel electrophoresis.

Purification, characterization, and functional properties of a novel glycoprotein from tartary buckwheat (Fagopyrum tartaricum) seed

A pure glycoprotein (BGP4-I) was obtained from tartary buckwheat seeds by aqueous extraction followed by DEAE-Sepharose Fast Flow ion exchange chromatography and Sephadex G-100 gel filtration chromatography. The average molecular weight of BGP4-I, as determined by high performance gel permeation chromatography, was 123.43 kDa. The structure of BGP4-I was characterized based on Fourier transform infrared spectroscopy, circular dichroism spectroscopy, and nuclear magnetic resonance spectroscopy, etc. Based on the nano-liquid chromatography-coupled electrospray ionization mass spectrometry analysis of the amino acid sequence of BGP4-I, belongs unequivocally to the glycosyl hydrolase family 1 in the Carbohydrate Active Enzymes database by alignment studies. The specific activity of BGP4-I was 18.44 μmol/min/mg on the substrate p-nitrophenyl-β-d-glucopyranoside. Furthermore, BGP4-I is unique in its specificity for some substrates. These results suggest that the BGP4-I from tartary buckwheat seeds is a novel specific β-glucosidase setting the foundation for potential applications in the food industry.

A novel antimicrobial protein of the endophytic Bacillus amyloliquefaciens and its control effect against Fusarium chlamydosporum

Fusarium chlamydosporum is the causal agent of stem rot in Jacaranda acutifolia. Bacillus amyloliquefaciens is an endophytic bacterium that shows promising biological control activity against F. chlamydosporum. In this study, B. amyloliquefaciens was cultured in a fermentation broth, and the main antimicrobial substance in the fermentation broth was isolated using the ammonium sulfate precipitation method and purified by DEAE sepharose fast flow weak anion exchange chromatography and sephadex G-50 molecular sieve chromatography. Polyacrylamide gel electrophoresis revealed a single antimicrobial protein with a molecular weight of approximately 29.0 kDa. The antimicrobial protein is a strong antagonist against F. chlamydosporum, leading to mycelial deformity, unclear mycelial septa, and isolated and granulated intracellular protoplasm. The N-terminal eight-amino acid sequence, NH2-Gly-Arg-Pro-Leu-Pro-Leu-Ala-Ala, was determined using the automatic Edman degradation method. BLAST analysis indicated that the amino acid residue sequence at positions 154–161 shows 100% homology to the hypothetical protein of Chromobacterium sp. LK1. However, no known homologous antimicrobial protein was identified, indicating that we have isolated a novel antimicrobial protein.

Isolation, structural characterizations and bioactivities of exopolysaccharides produced by Bacillus licheniformis

Extraction polysaccharide from microorganism is a research hotspot. In this work, a new type of water-soluble exopolysaccharides (EPS) was isolated from Bacillus licheniformis. Firstly, response surface methodology (RSM), based on a three-level, three-factor, was used to determine optimum conditions for EPS extraction. And RSM analysis indicated optimum condition was at the temperature of 8 °C for 10.44 h with ethanol at a concentration of 79.22% (v/v), the maximum yield of EPS was 3.07 g/mL. Secondly, EPS were seperated using DEAE-Sepharose Fast Flow column chromatography and acquired two polysaccharide fractions, BL-P1 and BL-P2. BL-P1 had larger molecular weight than BL-P2 from structural analyses, because of higher content of mannose, ribose, glucuronic acid, galactose, arabinose and fructose in BL-P2. Moreover, the characterization of BL-P1 and BL-P2 was investigated with Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy, the results indicated that EPS was mainly composed of→3)-α-d-Galp-(1→, →3,5)-α-l-Araf-(1→, →3)-β-d-Glcp-(1→, β-d-Glcp-(1 → and→4)-β-l-Fucp-(1 → 4)-β-d-Xylp-(1 → 4)-α-l-Rhap (1 → 3) -β-d-Manp-(4 → residues. In vitro antioxidant activity assay, EPS exhibited potent quenching capacities on hydroxyl and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radicals in a dose-dependent manner. Furthermore, BL-P2 had higher activity than BL-P1 in inhibiting α-amylase and α-glucosidase, which would have potential to be applied in nutraceutical and pharmaceutical industries.

Purified fraction of polysaccharides from Fuzhuan brick tea modulates the composition and metabolism of gut microbiota in anaerobic fermentation in vitro

One purified fraction from crude Fuzhuan brick tea polysaccharides (FBTPS), FBTPS-3, was obtained through column chromatography of DEAE Sepharose Fast Flow. The chemical properties and probiotic effects of FBTPS-3 were evaluated by fermentation in vitro. Moreover, the effects of FBTPS-3 on the function and metabolic pathway of gut microbiota were investigated by metagenomic sequencing. The results showed that FBTPS-3 was an heteropolysaccharide with molecular weight of 741 kDa, which was mainly composed of Man, Rha, GalA, Gal and Ara in molar ratio of 8.7:15.5:42.2:19.7:13.9. The contents of carbohydrates and uronic acid in FBTPS-3 were 44.78 ± 2.85% and 40.4 ± 2.11%, respectively. After fermentation, the molecular weight of FBTPS-3 and content of carbohydrates were significantly decreased, indicating that FBTPS-3 could be utilized by gut microbiota. Furthermore, the relative abundances of Bacteroides, Megasphaera and Prevotella were significantly increased by FBTPS-3. FBTPS-3 also significantly promoted the production of acetic, propionic and n-butyric acids. Based on the metagenomic sequencing, it was found that FBTPS-3 significantly enriched the metabolic pathway of starch and sucrose. All the results suggest that FBTPS-3 is expected to be developed as functional ingredients or foods to improve the host health through regulating the gut microbiota and physiological metabolic functions.

Optimization of ultrasonic-assisted enzymatic extraction of polysaccharides from thick-shell mussel (Mytilus coruscus) and their antioxidant activities

This study aimed to obtain the purified fractions of Mytilus coruscus polysaccharides (MCPs) and investigate their antioxidant activities. MCPs were prepared through ultrasonic-assisted enzymatic extraction optimized by employing the response surface methodology. A single-factor experiment was conducted using the Box–Behnken design to determine the optimum extraction conditions of MCPs. The ultrasonic power was 60 W, liquid-to-material ratio was 30 mL/g, extraction time was 36 min, extraction temperature was 64 °C, enzyme concentration was 3.2%, and polysaccharide extraction yield was 12.86% ± 0.12%. A novel polysaccharide (MCP1-2) was obtained after the purification with AB-8 macroporous resin, DEAE Sepharose Fast Flow, and Sepharose CL-6B column. The molecular weight of MCP1-2 was estimated to be 134.9 kDa according to high-performance gel permeation chromatography. High-pressure liquid-phase chromatography results showed that MCP1-2 contained mannose, rhamnose, glucuronic acid, glucose, galactose, and L-Fuc at a molar ratio of 1.53:1:4.83:81.82:2.36:1.51. Infrared and NMR spectroscopies confirmed that MCP1-2 possessed α- and β- configurations. The antioxidant activities of MCP1-2 were investigated in vitro, and the results showed that MCP1-2 had good antioxidant activity and can be used as a natural antioxidant in food.

Structural characterization and immunoregulatory activity of a novel heteropolysaccharide from bergamot (Citrus medica L. var. sarcodactylis) by alkali extraction

Bergamot is an ornamental plant and important traditional Chinese herbal medicine of tremendous value in economic and medicinal applications, mainly distributed in southern and southeastern China. Polysaccharide is one of active components of bergamot. In this study, CMSPB80 was extracted from bergamot by alkali solution and purified by DEAE Sepharose fast flow and Sephadex G-75 column to obtain a homogeneous heteropolysaccharide (CMSPB80-1), with a molecular weight of 103 kDa. Ion chromatography analysis indicated that CMSPB80-1 was composed of →3)-α-L-Rhap-(1→, →5)-α-L-Araf-(1→, →3,6)-α-D-Manp-(1→, →3)-β-D-Galp-(1→, →4,6)-α-D-Glcp-(1→, →6)-β-D-Galp-(1→ and a terminal α-D-Glcp. Scanning electron microscope (SEM) demonstrated that CMSPB80-1 was rough with a sheet-like and irregular structure. Atomic force microscopy (AFM) displayed CMSPB80-1 was branched and entangled with globular aggregates instead of a triple-helix structure. In addition, in vitro activity of CMSPB80-1 was evaluated by neutral red up-take assay and production of nitric oxide (NO) assay, which provided evidence that CMSPB80-1 could enhance macrophage phagocytiosis and promote splenocyte lymphocytes proliferation. The results proposed that CMSPB80-1 was suitable for health care and food/pharmaceutical industries as an immunoregulatory activity ingredient.

Isolation of homogeneous polysaccharide from Poria cocos and effect of its sulfated derivatives on migration of human breast cancer MDA-MB-231 cells

SATB1 plays a crucial role in the invasion and metastasis of breast cancer,and inhibition of SATB1 expression can effectively control breast cancer metastasis. In this study,homogeneous polysaccharides were isolated from Poria cocos and their sulfated derivatives were prepared to screen out the polysaccharide compositions with inhibitory effects on SATB1 expression. Smal-molecule components were removed from P. cocos by ethanol extraction,and P. cocos crude polysaccharide PPS was obtained by water extraction and ethanol precipitation. Then PPS was successively separated by DEAE Sepharose fast flow anion-exchange and Superdex-75 gel permeation chromatographic steps to give PPSW-1. The structure of PPSW-1 was identified and its sulfated derivatives were prepared. Then their inhibitory effects on human breast cancer MDA-MB-231 cells were investigated. A kind of polysaccharide,PPSW-1 with inhibitory effect on human breast cancer MDA-MB-231 cells,was obtained from P. cocos,with a relative molecular weight of 3. 06×104,and structure of 1,6-branched 1,3-α-D-galactan. PPSW-1 and its sulfated derivative Sul-W-1 showed good inhibitory effect on cells migration,and the water solubility of Sul-W-1 was better than that of PPSW-1. In addition,it was found that polysaccharide of P. cocos and its sulfated derivative can inhibit expression of SATB1. In this study,a kind of homogeneous polysaccharide with inhibitory effect on human breast cancer MDA-MB-231 cells was isolated from P. cocos,and its sulfated derivative with similar efficacy but better solubility was prepared,laying the foundation for the substance basis study of P. cocos.

Purification and characteristics of a new milk-clotting enzyme from Bacillus licheniformis BL312

A new milk-clotting enzyme (MCE) was produced from Bacillus licheniformis BL312. The characteristics of BL312 MCE were compared with those of Calf rennet, R. miehei MCE, and Chymopapain. BL312 MCE showed a remarkable activity of 5291 SU/mg after purification by ammonium sulfate fractionation and DEAE-Sepharose Fast Flow, which yielded 5.09-fold purification with a recovery of 39.24%. The purified BL312 MCE gave a single protein band on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gel, corresponding to 27 kDa. The αs-casein (αs-CN) and β-casein (β-CN) hydrolysates generated by BL312 MCE were different from those by Calf rennet, R. miehei MCE, and Chymopapain through SDS-PAGE and reversed-phase HPLC (RP-HPLC) analyses. The main cleavage sites in κ-casein (κ-CN) were the Met106-Ala107 and Asn123-Thr124 bonds for BL312 MCE, as determined by mass spectrometry analysis. BL312 MCE hydrolyzed αs-CN to a greater level than β-CN. It was stable at a wide pH range of 5.5–11.0 and temperature below 45 °C. The milk-clotting activity (MCA) reached the maximum when the substrate contained 50 mM CaCl2 at pH 5.5. The optimal temperature of MCE was 55 °C. The successful application in Monascus-fermented cheese production confirmed the usefulness of BL312 MCE in food and dairy processing.

An alkali-extracted polysaccharide from Zizyphus jujuba cv. Muzao: Structural characterizations and antioxidant activities

An acidic polysaccharide (SAZMP3) was isolated from jujube fruit residues by alkaline extraction and purified with DEAE-Sepharose Fast Flow and Sephacryl S-300 column chromatography. The structural characterizations of SAZMP3 were determined by high-performance gelpermeation chromatography, gas chromatography, Fourier transform infrared spectroscopy, methylation analysis, NMR spectroscopy, scanning electron microscopy, and atomic force microscopy. The results determined SAZMP3 was an acidic polysaccharide mainly contained rhamnose, galactose, and galacturonic acid with a molecular weight of 9.37 kDa and its backbone might mainly be composed of 1,4-α-D-GalAp with side chains of 1,3-β-D-Galp, 1,3,5-linked Araf, 1,2,4-α-L-Rhap and terminals of 1-linked Araf, 1-linked Rhap, 1-linked Galp by methylation and NMR analysis. Besides, SAZMP3 has shown potential antioxidant activity in scavenging free radicals suggesting that it is an antioxidant agent, which might contribute to the functional food qualities of jujube fruit.

Ultrafiltration isolation, hypoglycemic activity analysis and structural characterization of polysaccharides from Brasenia schreberi

Brasenia schreberi (B. schreberi) is a rare and precious vegetable, which coat with a gelatinous mucilage. This study is aiming to investigate the relationship between structural characteristics and hypoglycemic activities of polysaccharides with different molecular weight (Mw) range. Three polysaccharides fractions, namely BSP-U100 (50–100 kDa), BSP-U50 (10–50 kDa) and BSP-U10 (<10 kDa), were isolated from B. schreberi mucilage using ultrafiltration method. Compared to other polysaccharide samples, only BSP-U100 had a triple helix structure and existed as the ordered structure in aqueous solution. Furthermore, BSP-U100 exhibited higher α-amylase (IC50 = 0.4414 mg/mL) and α-glucosidase (IC50 = 0.5993 mg/mL) inhibitory activity. A heteropolysaccharide BSP-1a, which average Mw was 83.98 kDa, was purified from BSP-U100 by DEAE Sepharose Fast Flow and Sephadex G-75 column. D-galactose (66.85%), d-glucose (2.05%) and D-mannose (1.65%) were three main monosaccharides of BSP-1a. Structural characterization of BSP-1a showed that BSP-1a might be a kind of L-D-pyranose type galactose and mainly composed of α-1 → 6-linked Galp, α-1 → 3-linked Manp and α-1 → 4-linked Glcp. This study provided a theoretical basis for the development and application of B. schreberi polysaccharides as a potential anti-diabetic supplement.

Isolation, structure elucidation, and immunostimulatory activity of polysaccharide fractions from Boswellia carterii frankincense resin.

Frankincense has a long history in religious, cultural, and medicinal use. In this study polysaccharides were extracted from frankincense from Boswellia carterii. The polysaccharides were purified by anion exchange chromatography on a DEAE-Sepharose Fast Flow 16/10 FPLC column. Six fractions were obtained and the three most active immunomodulatory fractions were further purified by size exclusion chromatography on a Superdex-200 column. The composition showed the monosaccharides present were predominantly galactose, arabinose, and glucuronic acid along with small amounts of rhamnose and glucose. The monosaccharide composition and glycosyl linkage analysis revealed the polysaccharides belong to the type II arabinogalactans. Fourier-transform infrared spectroscopy and bicinchoninic acid assay showed that the amount of protein in the samples was <1 wt%. One-dimensional 1H NMR were consistent with high molecular weight compounds. The monosaccharides were primarily in the β conformation. The three fractions exhibited an immunostimulatory effect on RAW 264.7 murine macrophage cells. The most active immunostimulatory fraction FA2, stimulated a range of pro-inflammatory mediators including iNOS, NO, TNF-α, and IL-6 in RAW 264.7 cells. The fractions were effective in proliferating primary murine splenocytes. The results indicate that the polysaccharides isolated from frankincense have the potential to be used as an immunological stimulant or nutraceutical.

Screening, purification, and characterization of an extracellular lipase from Aureobasidium pullulans isolated from stuffed buns steamers

An extracellular lipase from Aureobasidium pullulans was obtained and purified with a specific activity of 17.7 U/mg of protein using ultrafiltration and a DEAE-Sepharose Fast Flow column. Characterization of the lipase indicated that it is a novel finding from the species A. pullulans. The molecular weight of the lipase was 39.5 kDa, determined by sodium dodecyl sulfonate-polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme exhibited its optimum activity at 40 °C and pH of 7. It also showed a remarkable stability in some organic solutions (30%, v/v) including n-propanol, isopropanol, dimethyl sulfoxide (DMSO), and hexane. The catalytic activity of the lipase was enhanced by Ca2+ and was slightly inhibited by Mn2+ and Zn2+ at a concentration of 10 mmol/L. The lipase was activated by the anionic surfactant SDS and the non-ionic surfactants Tween 20, Tween 80, and Triton X-100, but it was drastically inhibited by the cationic surfactant cetyl trimethyl ammonium bromide (CTAB). Furthermore, the lipase was able to hydrolyze a wide variety of edible oils, such as peanut oil, corn oil, sunflower seed oil, sesame oil, and olive oil. Our study indicated that the lipase we obtained is a potential biocatalyst for industrial use.

Characterization of Moringa oleifera roots polysaccharide MRP-1 with anti-inflammatory effect.

Moringa oleifera is a mutli-purpose herbal plant which has attained enormous attention as a natural source of nutrients and folk medicine. This work aimed to get a novel polysaccharide, termed MRP-1, which was isolated from Moringa oleifera roots with hot water extraction method followed by ethanol precipitation and purified with DEAE-Sepharose Fast Flow column. Monosaccharide composition analysis based on GC-MS showed that MRP-1 mainly consisted of Rha, Ara, Fru, Xyl, Man and Gal in the molar ratio of 1.5:2.0:3.1:6.0:5.3:1.1. The Roman spectra, FT-IR and NMR analysis showed that the typical features of carbohydrates, such as α-Araf, α-Gly, β-Galp, α-GalpA and β-Gly was contained by MRP-1. The LPS-induced RAW264.7 macrophage cells were used to evaluate the anti-inflammatory activity of MRP-1. The result demonstrated that the increasing of NO and TNF-α production induced by LPS could be prevented by different concentrations of MRP-1 treatment. Moreover, the mRNA expression level of iNOS induced by LPS was decreased significantly (p < 0.05) by MRP-1 treatment while show no obvious effect on the COX-2 mRNA expression. This study may provide new possible application of Moringa oleifera root polysaccharide related to anti-inflammation.

Chemistry and immunostimulatory activity of a polysaccharide from Undaria pinnatifida

An immunologically active polysaccharide named as UPP-2 (1035.52 kDa) was isolated from Undaria pinnatifida using traditional water extraction followed by DEAE Sepharose fast flow chromatography. UPP-2 was proven to be a low sulfated polysaccharide with relatively abundant uronic acid (13.08 ± 0.67%). UPP-2 mainly consisted of xylose (64.55%), glucose (23.81%), arabinose (5.90%) and mannose (4.26%), and its main glycosidic linkage types included →2)-α-D-Xylp-(1→, →4)-α-D-Glcp-(1→, α-D-Xylp-(1→ and →2,4)-β-D-Xylp-(1 → . Results indicated that UPP-2 significantly promoted the proliferation and pinocytic capacity of RAW264.7 cells, and upregulated the mRNA expressions of iNOS, TNF-α, IL-6 and IL-1β at 100–600 μg/mL with a maximum of 195, 42, 768 and 539 times of those of the negative control, respectively. Moreover, UPP-2 significantly increased the secretions of nitric oxide, TNF-α and IL-6 at 100–600 μg/mL (8.0, 73.1 and 188.7 times compared to those of the negative control, respectively), as well as promoted the production of IL-1β obviously at 600 μg/mL. Overall, UPP-2 could be served as a potential dietary supplement or functional food based on its immunostimulatory activity.

A novel application of ion exchange chromatography in recombinant hepatitis B vaccine downstream processing: Improving recombinant HBsAg homogeneity by removing associated aggregates

Production of recombinant HBsAg as a main component of the hepatitis B vaccine has already been established in commercial scale. So far, many studies have been performed to optimize the production process of this recombinant vaccine. However, still aggregation and dissociation of rHBsAg virus-like particles (VLPs) are major challenges in downstream processing of this biomedicine. The structural diversity of rHBsAg is dependent on many factors including cell types, molecular characteristics of the expressed recombinant rHBsAg, buffer composition as well as operation condition and specific characteristics of each downstream processing unit. Hence, it is not relatively easy to implement a single strategy to prevent aggregation formation in already established rHBsAg production processes. In this study, we examined the efficacy of weak anion exchange chromatography (IEC)- packed with DEAE Sepharose Fast Flow medium- on isolation of rHBsAg VLPs from aggregated structures. For this purpose, the influence of ionic strength of elution buffer as a key factor was investigated in isolation and recovery of rHBsAg VLPs. The elution buffer with electrical conductivity between 27 and 31 mS/cm showed the best results for removing aggregated rHBsAg based on SEC-HPLC analysis. The results showed that in the selected conductivity range, about 79% of rHBsAg was recovered with purity above 95%. The percentage of rHBsAg VLPs in the recovered sample was between 94% and 97.5% indicating that we could obtain highly homogeneous rHBsAg within the acceptable quality level. The TEM, SDS-PAGE and western blot analysis were also in agreement with our quantitative measurements.

Effects of ginseng neutral polysaccharide on gut microbiota in antibiotic-associated diarrhea mice

To investigate the effect of ginseng neutral polysaccharide on gut microbiota composition and diversity as well as the therapeutic effect for antibiotic associated diarrhea( AAD) in mice. The water-soluble ginseng neutral polysaccharide( WGPN) was purified from water-soluble ginseng polysaccharides( WGP) by DEAE-sepharose fast flow column,which was obtained from the roots of Panax ginseng. AAD mice were induced by gastric gavage with lincomycin hydrochloride,followed by administration of normal saline( natural recovery group,NR) or WGPN( WGPN group) for one week. Body weight changes,psychosis and diarrhea status were observed and assessed. 12 h after the last administration,histological observation of ileum and 16 S rRNA high throughput sequencing analysis of intestinal contents were conducted to identify the effects of WGPN on AAD mice. The results showed that WGPN could alleviate the symptoms of diarrhea in mice,decrease the inflammation and edema of ileum,and increase the length of intestinal villi. As compared to NR mice,WGPN could increase the relative abundance of Lactobacillus,and significantly decrease the relative abundance of Bacteroides,Streptococcus,Ochrobactrum and Pseudomonas at the genus level. In conclusion,WGPN could improve the gut microecology by recovering the ileum structure and improving the diversity and composition of the gut microbiota in AAD mice.

Structural characterization and immunoregulatory activity of a new polysaccharide from Citrus medicaL. var. sarcodactylis.

A new homogeneous heteropolysaccharide (CMSPA90-1) was purified from bergamot by DEAE sepharose fast flow and Sephadex G-75 columns, and was shown to have a molecular weight of 17.6 kDa. Its chemical structure was elucidated by acid hydrolysis and methylation analysis, along with high-performance anion-exchange chromatography, Fourier transform infrared spectroscopy coupled with gas chromatography-mass spectrometry, NMR spectroscopies, the Congo red test, and circular dichroism. CMSPA90-1 consisted of a pyranoside and funanside with branches containing α- and β-configurations simultaneously. Arabinose and glucose might form an arabinoglucan backbone. The ultrastructure of CMSPA90-1 was further characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The results of thermogravimetric analysis (TGA) revealed that CMSPA90-1 had good thermal stability. The results of DPPH˙ and ABTS+˙ radical scavenging assays indicated that CMSPA90-1 exhibited free-radical-scavenging properties. Otherwise, CMSPA90-1 could promote the proliferation of mouse splenocytes and the neutral red phagocytosis of RAW264.7 cells, which indicated that CMSPA90-1 could be researched and developed as one of the potential functional foods or natural medicines.

In vitro and in vivo evaluation of an exopolysaccharide produced by Lactobacillus helveticus KLDS1.8701 for the alleviative effect on oxidative stress.

Correlations between oxidative stress and degenerative diseases have been gaining increasing attention. A number of studies affirm that exopolysaccharide (EPS) produced by lactic acid bacteria (LAB) can alleviate oxidative stress and further prevent the related diseases. In our previous study, Lactobacillus helveticus KLDS1.8701 has been shown to possess high antioxidant capacity in vitro. The aim of this study was to evaluate the ameliorative effects of EPS produced by L. helveticus KLDS1.8701 on oxidative stress. Firstly, EPS was isolated from the culture of L. helveticus KLDS1.8701 and purified using DEAE-Sepharose Fast Flow chromatography. Secondly, the antioxidant capacities of EPS fractions were evaluated using in vitro methods. Thirdly, an in vivo study was performed to investigate the possible protective effects of EPS on d-galactose (d-gal)-induced liver damage and gut microbiota disorder. In vitro antioxidant activity results suggested that EPS-1 exhibited strong scavenging properties on 2,2-diphenyl-1-picrylhydrazyl radical, superoxide radical, hydroxyl radical, and chelating activity on ferrous ion. In vivo, EPS-1 supplementation significantly attenuated oxidative status such as decreased organic index, liver injury and liver oxidative stress. EPS-1 supplementation shifted the gut microbiota composition to that of the control group. In addition, the analysis of Spearman's rank correlation suggested that the protective effects of EPS correlated with manipulating the gut microbiota composition in d-gal-induced mice. These results implied that EPS-1 supplementation could mitigate hepatic oxidative stress via manipulating the gut microbiota composition and be used as a potential candidate to attenuate oxidative damage.