Study On Extracting Technology And Physicochemical Characteristics Of WPG From Bifidobacterium Infantis

The way to increase cell permeability had been reseached, so that exogenous enzyme could easily enter into cells and react with corresponding substrates. At last a short-cycle preparation method had been developed to extract whole peptidoglycan,and such preparation method would promote the actual production and application of whole peptidoglycan. Experiment and the results are as follows:Through the use of different treatment techniques, such as dialysis, freeze-thaw, bead grinding, lysozyme, phosphorus removal, makesure TCA can effectively remave teichoic acid, increase cell permeability, through optimizing to determine the extraction route for Peptidoglycan as follows: 10% TCA heated at 70℃for 1 hr while stirring, and then skimming for 24 hrs using sodium acetate, chloroform, and methanol mixture, then treated with trypsin and alkaline protease of 3500U for 12 hours, finally, passed through centrifugal washing to remove impurities. The modified method of extracting whole peptidoglycan is not only shortened the time of extraction, but aslo enhanced the yield.Prepared Bifidobacterium infantis whole peptidoglycan samples through modified method, their amino acid composition analysis results, amino-hexose ( 20.04 mg/g), total sugar (528.89 mg/g), total lipid(37.16 mg/g), protein (329.47 mg/g), phosphorus (0.21 mg/g) and TEM morphology are consistent with those of the peptidoglycan prepared using Sekine method. It showed that compared with Sekine method, the quality of whole peptidoglucan from modified method was not degradation. Detecting the effect of WPG from Bifidobacterium.infants inhibittum by MTT assay,if inhabiting rate of greater than 30 % as the standard for sensitivity, none of the whole bifidobacterium infantis, whole peptidoglycan, whole peptidoglycan's ultrasound breaking fragment samples are sensitive to breast cancer cells; 500ug of whole peptidoglycan sample(inhibition rate of 51.21%, the strongest effect), 100ug of whole peptidoglycan sample(inhibition rate of 34.77%) are sensitive to gastric cancer cells, which indicates the preservation of the structure integrity of peptidoglygcan could improve its effectiveness in tumor growth inhibition.