7 results about "Low molecular weight dextran" patented technology

The invention discloses a self-assembly enzyme for directional synthesis of uniform low molecular weight dextran, the self-assembly enzyme is named as YG-SpyTag-SpyCatcher-padex, the YG is a dextran sucrase gene (Genbank No.DQ345760), the padex is a dextran enzyme gene (Genbank No.KF999646.1), the SpyTag and the SpyCatcher are two specific oligopeptides, and aspartic acid in the SpyTag and lysine in the SpyCatcher spontaneously form an isopeptide bond. The invention belongs to the technical field of biology, and relates to an enzyme engineering technology. According to the invention, dextran sucrase derived from an escherichia coli genetically engineered bacterium BL21 (DE3)-YG-SpyTag and dextran enzyme derived from a pichia pastoris genetically engineered bacterium X33-SpyCatcher-padex are combined through a SpyTag-SpyCatcher protein covalent coupling system, and the obtained self-assembled enzyme can be used for catalyzing the substrate sucrose to be directly converted into dextran with the molecular weight of 3000 to 4000 Da.

The invention relates to the technical field of edible mushroom processing, in particular to low-molecular-weight hericium erinaceus beta-glucan with antioxidant activity as well as a preparation method and application of the low-molecular-weight hericium erinaceus beta-glucan. According to the method, the macromolecular hericium erinaceus beta-glucan is used as a raw material, the low-molecular-weight beta-glucan is prepared through microwave digestion and compound enzyme step-by-step degradation, the weight-average molecular weight of the prepared low-molecular-weight beta-glucan is 7.611 kDa, and compared with a high-molecular-weight beta-glucan sample, the low-molecular-weight beta-glucan is better in water solubility and lower in solution viscosity; the compound has the capability of efficiently scavenging free radicals, has good antioxidant activity, and has a wide application prospect.

The present invention relates to the technical field of cell culture, and specifically discloses a method for domesticating an adherent cell line into a fully suspended cell line. The adherent-dependent cells are inoculated on microcarriers and cell proliferation is carried out in DMEM medium containing 10% fetal bovine serum. After the cells proliferate to 10E6 cells / mL, the microcarriers are lysed, the cell clusters are centrifuged and collected. The cell clusters are inoculated in a medium containing 10% fetal bovine serum, 0.1% shear force protectant, and 2 g / L glucose and cultured at a rotation speed of 30 to 50 rpm for 3 to 4 days to enable the cells to form embryoid body clusters of 50 μm to 150 μm. The embryoid body clusters are mechanically pipetted to disperse them, and are domesticated for 18 to 22 days with DMEM medium containing different concentration gradients of low molecular weight dextran sulfate to obtain a successfully suspended and domesticated cell line. The method of the present invention improves the uniformity of cell embryoid bodies, makes the properties of the embryoid bodies more stable, and can efficiently obtain a suspended cell line.

This invention relates to the field of animal reproductive regulation technology, and discloses a twinning regulator for sika deer males that synchronize estrus and its application method. The regulator is a homogeneous and transparent sol system prepared from trehalose, pituitary follicle-stimulating hormone (FSH), medium- and low molecular weight sodium hyaluronate, low molecular weight dextran sulfate, zinc gluconate, and physiological saline. This invention utilizes sodium hyaluronate of a specific molecular weight and dextran sulfate to construct a polysaccharide sol network, combined with the cross-linking effect of zinc gluconate and the physicochemical stabilizing effect of trehalose, to encapsulate and slowly release FSH. The application method includes implanting and removing a vaginal silicone plug, combined with the injection of pregnant mare serum gonadotropin (PMSG) and the regulator, followed by natural mating. This invention prolongs the half-life of exogenous hormones in the animal, avoids drastic fluctuations in blood drug concentration, and improves the stability of twinning rates in sika deer.

The application discloses use of a low molecular weight dextran sulfate derivative in preparation of an anticoagulant drug, the low molecular weight dextran sulfate derivative is shown as formula (I), wherein a main connection mode is an alpha-(1, 6)-glycosidic bond main chain, relates to a weight average molecular weight (M w )≤40 kDa, and each glucose unit has at least 1.0-2.0 sulfate groups on average, wherein the low molecular weight dextran sulfate derivative has a high selective inhibitory activity on a blood coagulation factor X enzyme, so as to inhibit an endogenous blood coagulation pathway; can effectively inhibit thrombosis in vivo and in vitro, and has potential as a novel endogenous anticoagulant.

The present invention reveals that a low-molecular-weight polysaccharide prepared from a ginseng-derived water-soluble high-molecular-weight polysaccharide by means of enzymatic degradation is a low-molecular-weight ginseng glucan polysaccharide (L-GPS) which is a type of glucan composed of 96% or more of glucose, has a backbone structure of α-1,4-linked glucose, and has a molecular weight of 3,400 Da. In addition, the present invention confirms a novel functionality related to an inflammatory bowel disease (IBD) alleviation effect of this L-GPS.

The invention relates to the technical field of CIK cell cryopreservation, in particular to a gel preparation for CIK cell cryopreservation and a preparation method and application thereof. The skin care solution is specifically prepared from sodium hyaluronate, sodium carboxymethyl cellulose, guaiacol, human serum albumin, ornithine, L-proline, low-molecular dextran, dimethyl sulfoxide, 1-aniline, isomaltose oligosaccharide, glutathione, propylene glycol alginate tobramycin, povidone and the balance of water. The skin care solution is prepared from the following raw materials: sodium hyaluronate, sodium carboxymethylcellulose, guaiacol, human serum albumin, ornithine, L-proline, low-molecular dextran, dimethyl sulfoxide, 1-aniline, isomaltose oligosaccharide, glutathione, propylene glycol alginate tobramycin, povidone and the like. The gel preparation provided by the invention can be used for long-time cryopreservation of CIK cells, and the survival rate of immune cells can still reach 96.4% after the CIK cells are preserved for 12 months.