35 results about "Low molecular weight dextran" patented technology

Disclosed are hybrid genes of glucanase and dextransucrase, recombinant vectors comprising said hybrid genes, microorganisms which are transformed with said recombinant vectors, hybrid enzymes which are expressed from said hybrid genes, and processes for preparing isomalto-oligosaccharides or dextran using said microorganisms or enzymes. Expensive isomalto-oligosaccharides and low molecular weight dextran for clinical use can be produced simply and effectively from cheap substrate-sucrose, using a single bacterial strain or enzyme.

The invention discloses a method for preparing medium-low molecular weight dextran by using a biological method. The method comprises the following steps: adding a leuconostoc mesenteroides seed solution in a fermentation medium containing sucrose for carrying out fermentation culture; then adding a penicillium cyclopium seed solution or fermentation broth supernate of the penicillium cyclopium for continuously fermenting and culturing; and separating dextran from the fermentation broth to obtain the medium-low molecular weight dextran. The invention further discloses the prepared dextran and application thereof. The invention provides a method for directly obtaining the medium-low molecular weight dextran by using the biological method in a mode of coupling fermentation of double microorganisms. The medium-low molecular weight dextran is synthesized by directionally regulating and controlling through the biological method, so that the generated dextran degrades to form dextran which tends to be required by clinical application. Meanwhile, according to the method disclosed by the invention, ethanol precipitation can be directly carried out, and thus redundant, time-consuming and noble gradual dividing precipitation is omitted, the yield of the dextran is increased, and the use amount and the consumption of ethanol are reduced.