Study On The Extraction Technology Of Functional β-glucan From G.Lingzhi Fermentation Broth

Polysaccharides are the key medicinal components from Ganoderma lingzhi, and P-glucan is the most active ingredients of Glingzhi polysaccharide, which have various pharmacological effects. At present, more study on the extraction of total polysaccharides from Glingzhi, but the study on the extraction of β-glucan from G.lingzhi was seldom reported. Therefore, this work is aimed to obtain β-glucan from G.lingzhi by making a study on extraction technology of β-glucans from Glingzhi fermentation mycelium extracellular and cell, and decolorization process of β-glucan from Glingzhi is optimized further. Aimed at the large scale preparation technique to provide the basis for further research on the fermentation of β-glucan from Glingzhi. The main results are as follows:1. Effects of two different strains (strain A and B) of the extraction yield of polysaccharide、β-glucans from Glingzhi fermentation mycelium extracellular and cell in the same cell culture fermentation and extraction conditions, as the results follows:fermentation broth of No. A strain polysaccharide content and β-glucan content were 1.358g/L and 0.020g/L, mycelia polysaccharide content and β-glucan content were 307.74mg/g and 1.90mg/g. As the concentration in fermentation broth of strain B, the content of polysaccharide was 0.802g/L, β-glucan content almost undetectable. mycelia polysaccharide content and β-glucan content were 204.83mg/g and 0.09mg/g. The results show that the polysaccharide and β-glucan content of No. A strain were significantly higher than that of B strain, therefore, we choose the strain A for further study of strain.2. The strain A as the object of study, through the comparison of the hot water reflux method, water+enzymolysis method, ultrasonic method and ultrasonic+enzyme (cellulose) method, the extraction technology of test of β-glucan from Glingzhi mycelia. The results showed that extraction of p-glucan from Glingzhi mycelia was significantly higher than that of the other three methods for extracting rate. The key parameters of ultrasonic+enzymolysis extraction technology of β-glucan from Glingzhi mycelia, ultrasound power(A), ratio of water to material(B), pH(C) and enzymolysis amount(D) were further optimized by single factor test.3. The Box-Benhnken experimental design and response surface analysis of these four key parameters are optimized, and the regression model which can predict yield of β-glucan from Glingzhi mycelia was obtained: Y=+5.71+0.22A+0.14B+0.18C+0.052D-0.078AB+0.035AC+0.052AD+0.075BC +0.040BD-0.098CD-0.50A2-0.34B2-0.61C2-0.44D2. The optimal levels of the four factors were:ultrasound power 244W, ratio of water to material 26:1(v/m, mL/g), pH 7 and enzymolysis(cellulose) amount 1.0%. Under these conditions, the yield of β-glucan from G. lingzhi mycelia was up to 5.71(mg/g). The validation tests showed that the result predicted by the model was similar to the actual extraction results, so the model can be used in practical application.4. The D301G macroporous adsorption resin was used as the best decoloring agent to decolorization of P-glucan from Glingzhi. And the key parameters of decolorization of β-glucan from Glingzhi were further optimized by single factor test and orthogonal test. The optimum decoloring conditions were:resin amount 3.0g, temperature 50℃, speed 160r/min, time 3.Oh, pH 4. The decolorization rate obtained in the experiment was 68.35%, retention rate of polysaccharide was 80.54% and retention rate of β-glucan was 52.17%.