Optimization Of Culture Conditions For Laccase Production From Polyporus Elegans Fr.

In the northeast of China, the great Xingan mountains and the Changbai Mountain region have extremely abundant fungi resources, especially the white rot fungus. These valuable resources were seldom reported, and there are many new laccase was not found. Laccase can oxidative degradation of a variety of toxic compounds, Fungal laccases can also depolymerized polymer, reunion, so far, the use of laccase in treatment of organic contaminants, biological bleaching pulp and the clarification of the beverage and other fields have been widely studied and applied. So the study of white rot fungus yellow porous bacteria growth and its producing laccase culture conditions to improve the enzyme activity is of great significance.Polyporus elegans Fr. belonging to the porous bacteria belonging to the fungi of basidiomycetes Aphyllophorales Polyporaceae, also known as variable quasi porous bacteria, can generate large fruiting. Fruiting bodies are medicinally important resource, in the treatment of kidney deficiency, lumbocrural pain, numbness, arrhythmia and grain bad disease has obvious effect, but also in improving body immunity, resist fatigue and also has remarkable curative effect. There are400kinds of porous bacteria in China have been reported. The western countries on the culture characteristics of a series of studies, demonstrated according to culture traits of porous bacteria classification system is complex, but has the application value.This study with the Polyporus elegans Fr.(Polyporus elegans Fr.) for the production of bacteria, optimization of fermentation conditions for laccase, and the immobilization of laccase were studied, yellow porous fungus laccase industrialized production and provide a theoretical basis for application. The main results are as follows:In the course of the experiment found that the Yellow porous fungus hyphae and mycelium fullness, thick, full growth, uniform, pure color, bright, bacterial secretion laccase activity was the highest.On the Polyporus elegans Fr. fermentation liquid of laccase production of culture medium and culture conditions were studied, with fermentation liquid of laccase activity to measure index, the optimum culture medium composition (1L):pH5.5, liquid volume80mL,8%inoculation quantity, the best carbon source is glucose+bran water (1:1), nitrogen source is urea, Mg2+concentration was1.5g/L, Cu2+concentration was0.1mmol/L, ferrous ion is0.15mmol/L, the best inducer for phenol.The Polyporus elegans Fr. by laccase optimal culture condition, using Minitab15software design Plackett-Burman test, effect of screening out enzyme production by three main factors, respectively, the ratio of carbon to nitrogen concentration of copper ions and pH. Using the statistical software Design-Expert experimental design and response surface analysis by regression analysis, regression equation is obtained by solving the optimization of the fermentation medium for:carbon to nitrogen ratio4.0030:1, copper ion concentration0.1015mmol/L and pH5.4755, can get the maximum enzyme activity, the predictive value of447.408U/mL, under this condition is developed and verified with experimental results the enzyme activity, with the theoretical predicted values coincide. And is enhanced to2.5times.To glutaraldehyde cross-linked chitosan sphere as carrier, was prepared by covalent binding immobilization enzyme, discusses the immobilization conditions and some properties of the immobilized enzyme was studied, repeated use and storage stability. The experimental results are as follows:Chitosan Immobilized Laccase, single factor experiment showed glutaraldehyde (cross-linking) of optimal concentration of10%, reaction time16h, the most suitable pH is5, to the amount of enzyme2mL,4DEG C storage immobilized laccase activity is best, immobilized enzyme and the optimum temperature of4℃.