Preliminary Study On The Breeding And Application Of Se-accumulating Strain Of Flammulina Velutipes

Flammulina velutipes is a nutritional and healthcare food with high protein, low heat, rich polysaccharide and long cultivated history ,and it has important medical and healthy function.Ultraviolet radiation mutagenesis of Flammulina velutipes F40 protoplasts was carried out. By the way of preliminary screening and exact screening, two mutants of Y12 and Y57 were obtained, those Se⁴⁺ contents and biomass are higher than original strain F40. The results of continued cultivation for 10 generations on PDA planes and tests of fermentation in shaking bottles, continued cultivation for 3 generations, and molecular identification of mutants by ISSR-PCR, ultimately showed that Se- accumulating stain Y57, with steady high biomass and high content of Se' was more excellent strains than original strain.Response surface methodology was used to optimize the fermentation condition of Se- accumulating Flammulina velutipes. The cornstarch and soybean meal were confirmed to be the suitable carbon and nitrogen source separately from the tested carbon and nitrogen source. Full Factorial Design was used to evaluate the influence of related 4 factors, the result showed that cornstarch and soybean meal were the main influence factors. The experiment of Steepest Ascent was used to approach the optimal response region of above two factors, then the Central Composite Designs and response surface analysis were used to confirm the optimal concentrations of main influence factors that cornstarch is 28.8g/L, soybean meal is 14.2 g/L .The kinetic models for mycelial growth and functional polysaccharide production were studied with Flammulina velutipes Y57.The fermentation was experimented in 50L bioreactor by batch. On the basis of Logistic and Luedeking&Piret equation, the mathematical kinetic models were established, involving cell growth, functional polysaccharide formation and substrate consumption. The parameters of the models were obtained. It showed that the predict values of the models and experimental data are in a good agreement, functional polysaccharide production was growth-associated and the models were applicable to predict the fermentation process of Flammulina velutipes.The technological process,methods of extraction, Flavor Prescription of Flammulina velutipes fermentative drink were preliminarily studied. With fermentative stock: Pure water ritio of 1:1,exacted by Ultrasonic,the effect of extraction was best.By use of...