Domesticated Cultivation Of Xinjiang Wild Mushroom Agaricus Balchaschensis And Laccase Activity

Special landforms and vegetation characteristics of The Xinjiang Uygur Autonomous Region gestates some unique wild edible and medicinal fungi species.We collected and identified 19 kind of wild edible and medicinal fungi species,among which Agaricus balchaschensis is big,high-quality,and popular by local people.Pure culture strain BCBH was isolated from wild fruiting bodies from county Bohu.Further studies were performed including biological characteristics and optimal culture conditions of mycelia,response surface optimization of extracellular laccase,and laccase purification from wild fruiting bodies using ion exchange and gel filtration chromatography.Based on molecular biological classification studies,the strain BCBH,Agaricus desjardinii and Agaricus sinodeliciosus were gathered in a class,and very close to Agaricus bisporus and Agaricus bitorquis with the genetic distance lower than 0.005.The mycelial growth of the Balkhash mushroom was inhibited by long time of low temperature treatment.NaCl concentration of 3.12 mM can enhance the mycelia growth.The optimal pH of mycelia was neutral to slightly acidic.The optimal carbo sources were maltose and soluble salts,the optimal nitrogen sources were ammonium nitrate and peptone.The response surface analysis showed that oval or saddle shaped contour lines can be formed by pairs of NaCl,maltose and ammonium nitrate.Maximum biomass can be obtained using 0.2 g/L NaCl,6 g/L maltose,and 1.5 g/L ammonium nitrate with the predicted value of 2.108 g/L.The measured value was 2.09 g/L with a difference of 0.85%.Sterilized raw materials cultivation was performed in the domesticated cultivation of the Balkhash mushroom using wheat straw,corn stalks,reed stalks,bran,pre-fermented straw and wheat grain.Fruiting bodies can be formed with the raw materials using commercial fermented material with wheat grain,while the mycelia can not growth on the cottonseed shell based media.The response surface simulation of the extracellular laccase activity was performed using the laccase activity as the response value,single factor and Box-Behnken analysis.The regression equation was:Y =-17.56408 + 2.03860X1-0.29335X2 + 0.18440X3 +0.083583X1X2-1.00000E-004 X1X3 + 9.71111E-003 X2X3-0.13368X1X1-0.12210X2X2-9.05528E-004X3X3,The optimal levels of the three major factors were sucrose of 10 g/L,yeast powders of 7 g/L,and the shaking speed of 150 r/min.The predicted value was 4.653 U/mL.A laccase was purified using the wild Balkhash mushroom with CM-cellulose and Q-Sepharose ion exchange chromatography,and gel filtration chromatography.It possessed a Mr.of 66 kDa with the N-terminal amino acid sequence of AVIIITVNM.The optimal pH and temperature of the purified laccase was 2.2 and 40?.It was stable in 4-50?,but highest inhibited by Hg2+.The laccase demonstrated high dye degradation activity towards erichrome black T with dye degradation ratio of 47.7%at 24 hr.It also had partial detoxification activity on malachite green.