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.

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.