Exogenous MnSO4 Improves Productivity of Degenerated Volvariella volvacea by Regulating Antioxidant Activity

Manganese is one of the trace elements necessary for organisms to maintain normal biological activities and is also a cofactor for manganese superoxide dismutase (Mn-SOD) and manganese peroxidase (MnP). In order to find a simple and effective method to rejuvenate the degenerated <i>V. volvacea</i> strains, we explored the effect of the exogenous addition of MnSO₄ on the antioxidant vigour and productivity of degenerated strains of <i>V. volvacea</i>. The results showed that the exogenous MnSO₄ had no significant effect on the non-degenerated strain T0, but it could effectively increase the mycelial growth rate, mycelial biomass, and LBL decolouring ability of the degenerated strains T10 and T19, and reduce the production cycle and increased the biological efficiency of T10; it helped the severely degenerated T19 to regrow its fruiting body; and it also significantly increased the viability of the matrix-degrading enzymes such as EG, Lac, Xyl, etc. of T10 and T19. Meanwhile, exogenous MnSO₄ significantly increased the activity of GPX, GR, CAT, SOD, and the content of GSH, polyphenols, minerals, and polysaccharides in T10 and T19 strains, which resulted in a significant decrease in the accumulation of ROS, such as O₂^- and H₂O₂ in T10 and T19. The correlation analysis showed that there was a significant correlation between antioxidant activity and the production ability of <i>V. volvacea</i>. This study can provide theoretical reference and technical support for the rejuvenation research of degenerated strains of <i>V. volvacea</i> and other edible fungi.