Glycerol Fermentation Strain Breeding And Optimization Of Process Conditions

Shell sugar (chito-oligosaccharide) for chitosan degradation products, has lowmolecular weight, is water-soluble, very easy to be absorbed by human body, makethe chitin series products of the best product application, have adjusting the humanbody immunity and anti-tumor effect, as a kind of functional oligosaccharide, inmedicine, food and other field has a broad prospect of application.This subject introduces a kind of soil from nature were studied in high yieldchitosanase Y1initial strains, by physical method in the uv irradiation mutagenesis,random screening and directional screening, yield chitosanase mutations S8researchprocess. In practical operation through the enrichment culture, purifying training,separation, can produce a strain get high yield chitosanase strains S8, and the strainsgrowth curve is tested and the results were chitosanase bacteria in the typical growthcurve. At the beginning of the screen to get Y1strains for starting strains, through theultraviolet mutagenesis screening, and a series of purification process, finally got aplant genetic stability is best, consumption sugar speed and chitosan enzymeproduction is higher than the Y1strains target S8strains.Test set up including16S rDNA D1/D2area series analysis and physiological andbiochemical tests of the classification and identification system, on the separation ofthe strains get S8classification and identification. In the practical operation will getthrough the sequencing of16S rDNA sequence in the Blast NCBI than, informed andthe sequence homology of higher known sequences for Bacillus cereus ATCC10987,the similarity is99.8%, so just confirmed for huge strains S8Bacillus; Then throughthe physiological and biochemical tests the specificity of the selected from the testevaluation results show the16SrDNA D1/D2area series analysis results.For high yielding to the optimization of the strains of the conditions offermentation, the final comparison chooses50*10-6g/ml of ironion to join the culturemedium, the optimal fermentation conditions for8%inoculated quantity, oxygen150r/min, hair30℃temperature, starting PH6.0, fermentation time96h, chitosandecomposition rate of30.2%.