Study On Breeding Of New Coriolus Versicolor Strain By Low Energy Nitrogen Ions Implantation

Coriolus versicolor is word wide distributed edible medicinal fungi.Recent studies have proven that the polysaccharide of Coriolus versicolor can enhance immunity,inhibit tumor,eliminate pain,fight inflammation,resist oxidation and fight the aging process,etc.This function makes it be not only an ideal medicine,but also an important raw material for health food and functional food.In this article,Coriolus versicolor AHSWYZ-07 strain as the original strain was implanted to mutagenize the protoplast coupled with low energy N+ ion.A high-yield strain was bred and the submerged fermentation process of that strain was optimized.Protoplast preparation is the prerequisite condition for protoplast breeding.There are many factors,which affects protoplast preparation.In this article,lywallzyme is selected to remove the cell wall of Coriolus versicolor AHSWYZ-07.Through experiments,it was found that the largest amount of protoplasts could be prepared when the age was 5d,and digested into 2%lywallzyme at 30? and pH6 for 5 hours with osmotion pressure stabilizer of 0.6 mol/L sucrose.Then,low-energy N+ ions of different concentrations were implanted to mutagenize the protoplast of AHSWYZ-07,and its survival rate followed a typical saddle-shaped curve.According to experiment,the mutagenesis effect was the best with ion implantation dose 10×10¹⁴ ions/cm² and implantation energy of 20KeV.By mutagenesis and screening,an excellent new strain was ultimately obtained:Coriolus versicolor SY-1027,with 21.92g/L maximum biomass during submerged fermentation and intracellular polysaccharide content of 2.27g/L,which improved 16.22%and 17.62%compared with the original strain,respectively.On the basis of acquiring a new excellent strain,this article uses intracellular polysaccharide as an indicator by way of flask-shaking submerged fermentation medium to optimize the submerged fermentation of SY-1027 and to determine the optimal culture medium:glucose 4%,corn flour 2.5%,soybean pulp powder 1.75%,corn steep powder 0.3%,KH2PO4 0.1%,MgSO4 0.08%and vitamin B1 10Omg/L.The optimal culture conditions were the natural pH,140r/min speed,100mL/500mL fluid loading volume,15%inoculums size,temperature 28?,and 6 days of submerged fermentation time.Under the above culture conditions,SY-1027 strain during submerged fermentation had a biomass of 28.13g/L and the intracellular polysaccharide content of 2.94g/L,and the capacity has been greatly improved compared with before,which improved 28.33%and 29.52%.