Gene Regulates the Synthesis of β-Glucan with Antioxidant Activity in the .

The ability of the fungus to regulate metabolism on various nitrogen sources makes it survive and metabolize in different environments. The biomass and the β-glucan yield of are closely associated with the nitrogen source. This study found the only GATA nitrogen source activation regulating factor in HIT-LCY. In order to testify the function, we amplified its conserved domain to build a silencing vector and used the RNAi to obtain the silent strain, and then explored its effect on the phenotype of and the yield of β-glucan. We found that the biomass and β-glucan yield of the silent strain decreased significantly after culturing with different nitrogen sources, in particular when using sodium nitrate and glutamate as the source. However, the β-glucan yield increased significantly after overexpression of Area, reaching 5.2 g/L when glutamine was the nitrogen source. In addition, the strain morphology changed as well under different nitrogen sources. At last, we investigated the antioxidant activity in vitro of β-glucan and found that it has a significant clearance effect on OH·, DPPH·, and ABTS·, being best with ABTS. Therefore, this study believed that the Area gene has a certain regulation function on the synthesis of β-glucan with antioxidant activity.