Immunomodulatory activities of proteins from Astragalus membranaceus waste.

BACKGROUND: Astragalus membranaceus is a traditional Chinese medicine that has a long history of medical applications. It is of interest to investigate the functional components of A. membranaceus waste with regard to its development and utilization and increasing resource utilization. RESULTS: The protein AMWP was isolated from the A. membranaceus waste. This protein was further purified by DEAE-cellulose-52 chromatography and Sephadex G-200 size-exclusion chromatography to obtain three fractions, named AMWPDG2, AMWPDG4 and AMWPDG6. Then, their immunomodulatory activities were evaluated by using cell model experiments. The results indicated that the protein fractions could significantly increase the proliferation of splenic lymphocytes, peritoneal macrophages and bone-marrow-derived cells (BMDCs). AMWPDG2 showed the highest immunocompetence. AMWPDG2, AMWPDG4 and AMWPDG6 not only significantly improved the phagocytosis and immunomodulatory factors (interleukin (IL)-6, tumor necrosis factor-α, nitric oxide, hydrogen peroxide) secretion of peritoneal macrophages, but also promoted the expression of inflammatory cytokines (IL-6, IL-12 p40, IL-1ß, IL-1α) and chemokines (CXCL1, CCL3) in BMDCs. CONCLUSION: Taken together, these results indicated that three protein fractions from the A. membranaceus waste might be a potential natural immunomodulator. Moreover, it also provided the theoretical basis for further researching the mechanism of AMWPDG2, AMWPDG4 and AMWPDG6 on improving the immune response. © 2019 Society of Chemical Industry.

Novel hydrocortisone magnetic molecularly imprinted polymers: Preparation, characterization, and application.

In this work, magnetic molecularly imprinted polymers (MMIPs) were prepared by a surface imprinting method using Fe3O4 nanoparticles as a support. The products were characterized by FT-IR spectroscopy, VSM, TGA, SEM, and TEM. Combined with HPLC, hydrocortisone in milk powder and milk were separated and purified, and their contents were monitored. The results showed that MMIPs with a particle size of approximately 1000 nm were successfully prepared. The adsorption mechanism of MMIPs was confirmed by kinetic adsorption and thermodynamic adsorption experiments; the maximum adsorption capacity was found to be 17.2 mg g-1, and adsorption equilibrium could be reached within 40 min. In the actual sample application, the recovery rates of milk powder and milk were 93.88-99.15% and 95.80-98.10%, respectively. These results showed that MMIPs had good performance in selectively identifying hydrocortisone and were suitable for determining hydrocortisone in milk products.

Ginger polysaccharides enhance intestinal immunity by modulating gut microbiota in cyclophosphamide-induced immunosuppressed mice.

In this study, the immunity-enhancing effect of ginger polysaccharides UGP1 and UGP2 on CTX-induced immunosuppressed mice was evaluated. The results showed that ginger polysaccharide could effectively alleviate the symptoms of weight loss and dietary intake reduction induced by CTX, increase fecal water content, reduce fecal pH, and protect immune organs of immunosuppressed mice. In addition, ginger polysaccharides also stimulated the secretion of cytokines IL-2, IL-4, TNF-α and immunoglobulin Ig-G in the serum of mice, increased the expression of Occludin and Claudin-1, and restored the level of short-chain fatty acids in the intestine to improve immune deficiency. Furthermore, ginger polysaccharides significantly reduced the relative abundance ratio of the Firmicutes and Bacteroidetes in mice and increased the relative abundance of Verrucomicrobia and Bacteroidetes at the phylum level. At the family level, ginger polysaccharides increased the relative abundance of beneficial bacteria such as Muribaculaceae, Bacteroidaceae and Lactobacillaceae, and decreased the relative abundance of harmful bacteria such as Rikenellaceae and Lachnospiraceae. Spearman correlation analysis indicated that ginger polysaccharides could enhance intestinal immunity by modulating gut microbiota associated with immune function. These results indicated that ginger polysaccharides have the potential to be a functional food ingredients or a natural medicine for the treatment of intestinal barrier injury.

[Determination of mineral elements in two grades of three green tea varieties by ICP-AES].

Green tea, a traditional healthy drink, has various necessary nutrients. A study was carried out on the contents of mineral elements such as Ni, Ba, Fe, Mn, Cr, Mg, Ca, Cu and Al in two grades of three green tea varieties by ICP-AES. The difference in contents of mineral elements between green teas was studied. The results indicated that there are different contents of mineral elements among varieties and grades of green tea. A basis for consumption, varieties identification and grades judgment was provided by the study.

Antidiabetic activities of glycoprotein from pea (Pisum sativum L.) in STZ-induced diabetic mice.

Polysaccharides have hypoglycemic activity and pea protein has high nutritional value. The purified pea glycoprotein PGP2 has been shown to inhibit the activity of α-glucosidase and α-amylase in previous studies. To study the mechanism of PGP2-induced blood glucose lowering in vivo, this paper established a diabetic mouse model by intraperitoneal injection of STZ and high-fat diet, and evaluated the blood-glucose-lowering activity of the pea component PGP2 at different doses. The results showed that intragastric administration of PGP2 could effectively reduce diabetic weight loss and polyphagia symptoms, reduce fasting blood glucose levels in mice, and improve oral glucose tolerance levels in mice. PGP2 could promote insulin secretion and had a protective effect on mouse organs. After intragastric administration of PGP2 in mice, the serum levels of total cholesterol, triglycerides and low-density lipoprotein decreased. PGP2 up-regulated the gene expression of insulin receptor substrates IRS-1 and IRS-2 in liver tissues, thereby reducing insulin resistance. Based on the above experimental results, PGP2 had good hypoglycemic activity and was expected to be developed as a natural medicine for the treatment of type II diabetes.

Characterization and antitumor activities of polysaccharides obtained from ginger (Zingiber officinale) by different extraction methods.

Three different extraction technologies including hot water extraction (HWE), enzyme assisted extraction (EAE) and ultrasonic cell grinder extraction (UCGE) were employed to extract crude ginger polysaccharides (GPs) under their respective best parameters, then crude GPs were purified by DEAE cellulose-52 and Sephadex G-200 size-exclusion chromatography in that order. Five GPs fractions (HGP, EGP1, EGP2, UGP1, and UGP2, respectively) were obtained. The differences of five GPs in chemical composition, characterization and antitumor activities were further compared. The molecular weights were different in five GPs, varying from 11.81 to 1831.75 kDa. Mannose and glucose as the main monosaccharide and the glycosidic linkage of →4)-α-D-Glc(1→ and -α-Manp-(1→ existed in both five GPs. While EGP2 and UGP1 possessed specific structure of →6)-ß-D-Galp-(1→ and UGP1 contained more sulfate group. Moreover, UGP1 exhibited strong inhibitory effect on three tumor cells especially the colon cancer. The inhibition rates of UGP1 on H1975, HCT116 and MCF-7 were 23.339 ± 2.285%, 56.843 ± 2.405% and 21.061 ± 1.920% respectively. The study indicated GPs extracted by UCGE could reserve more active structure and inhibit colon cancer more significantly.

Characterization and antioxidant activity of polysaccharides obtained from ginger pomace using two different extraction processes.

In this study, two different processes of hot water (HW) and ultrasonic-assisted (UA) for the extraction of polysaccharide from ginger pomace (GPPs) were employed under their respective best parameters, and the characterization and antioxidant activity of the purified polysaccharide (HW-GPP1, HW-GPP2, HW-GPP3, and UA-GPP1, UA-GPP2, UA-GPP3, respectively) were analyzed. The data implied that the yield of the polysaccharide obtained by UA was higher than that of HW. Meanwhile, two kinds of GPPs possessed the different preliminary structural characteristics including molecular weight distributions, total sugar and protein content, uronic acid content, while similar monosaccharide compositions and sulfuric radical contents. In vitro antioxidant activity assays indicated that UA-GPP3 showed the strongest scavenging abilities on DPPH radicals, while UA-GPP2 possessed the strongest scavenging abilities on hydroxyl and superoxide radicals. Moreover, the antioxidant activity of each fractions of GPPs extracted by UA was better than that of the corresponding fractions of GPPs extracted by HW. These results showed that UA was more beneficial to enhance the extraction yields of the polysaccharides, and also resulted in GPPs with higher bioactivity. Therefore, it indicated that UA-GPPs could be used as a potential natural antioxidant. Accordingly, the ginger pomace could be used as a potential source for natural antioxidant.

Preparation and in vitro absorption studies of a novel polysaccharide­iron (III) complex from Flammulina velutipes.

Iron is essential in fundamental bioactivities, so it makes sense to improve the efficiency of iron on epithelial transport. In this work, a novel polysaccharide­iron(III) complex (FVP-Fe(III)) was prepared from Flammulina velutipes with a specific structure. The FVP-Fe(III) had a molecular weight of 15.13 kDa with a monosaccharide composition of mannose, galacturonic acid, glucose, galactose, xylose, fucose in a molar ratio 3.6:2.1:60.8:18.7:3.9:10.9. In the vitro digestion model, the complex could maintain better solubility and steady of iron than FeSO4. In the cell assay, FVP-Fe(III) showed lower cytotoxicity and better absorption. The transport amount of FVP-Fe(III) was 1.5-fold of FeSO4 at same concentration and 1.8-fold of FeSO4 at same time. The transport was mediated by the peptide transporter (pepT1) active transport pathway and the efflux of the sample was mainly mediated by multidrug-resistance proteins (MRP) transporter. The results of this study suggested that the polysaccharide obtained from F. velutipes could be developed a new kind of iron delivery for further study.

Effects of polysaccharides from the base of Flammulina Velutipes stipe on growth of murine RAW264.7, B16F10 and L929 cells.

A polysaccharide (FVSP) was isolated from the base of Flammuliana Velutipes stipe, and FVSP was further purified by DEAE-cellulose-52 chromatography and Sephadex G-100 size-exclusion chromatography to obtain three fractions named FVSP-1, FVSP-2 and FVSP-3. Then their activation of macrophage cell RAW 264.7 and anti-proliferative effects to the murine melanoma B16F10 and fibroblasts L929 cells were evaluated by using the cell model experiments. The results indicated that the polysaccharide fractions could increase the proliferation and phagocytic activity of macrophage significantly and play an inhibited effect on the cancer cells. Moreover, the anti-proliferative activities of FVSPs increased with the participation of the antitumor factors induced from macrophage by polysaccharides fractions. Taken together, these results indicated that three polysaccharides fractions from the base of F. Velutipes stipe may be useful as potent antitumor agents for the prevention of tumorigenesis.

Antimicrobial and antioxidant activities of Flammulina velutipes polysaccharides and polysaccharide-iron(III) complex [corrected].

FVP is polysacchrides obtained from Flammulina velutipes. A polysacchride named FVP2 was isolated from FVP by DEAE cellulose-52 chromatography and Sephadex G-100 size-exclusion chromatography. FVP-Fe and FVP2-Fe were synthesized by neutralization of FeCl3 carbohydrate solution. The antibacterial and antifungal activities of FVP, FVP2, FVP-Fe, FVP2-Fe were investigated and their antioxidant effects on hydroxyl, 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide anion, 2,2'-azobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals, reducing power, inhibition of malondialdehyde (MDA) were assessed in vitro. The results suggested that FVP-Fe and FVP2-Fe significantly suppressed the growth of bacteria Staphylococcus aureus, Escherichia coli, and Bacillus subtilis, and have relatively strong antioxidant activity to scavenge superoxide anion radical. In addition, FVP exhibited strong antioxidant activity to eliminate hydroxyl, DPPH, ABTS radicals, had high reducing power and inhibited the MDA production of health mice liver homogenate induced by auto-oxidation and Fe2+-H2O2 system.

Isolation, purification and antioxidant activities of polysaccharides from Grifola frondosa.

The crude polysaccharides (GFP) were isolated from the fruiting bodies of Grifola frondosa and purified by DEAE cellulose-52 chromatography and Sephadex G-100 size-exclusion chromatography in that order. Three main fractions, GFP-1, GFP-2 and GFP-3, were obtained through the isolation and purification steps. Then the antioxidant activities of these three fractions were investigated in vitro. The results showed that GFP-1, GFP-2 and GFP-3 possessed significant inhibitory effects on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical and superoxide radical; their reducing power, ferrous ions chelating effect and the inhibition ability of the rat liver lipid oxidation where also strong. These results suggest that G. frondosa polysaccharides could be a suitable natural antioxidant and may be the functional foods for humans.