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Media components for the production of lignolytic enzyme MnP in the submerged fermentation from Clitopilus scyphoides were screened by PB design of experiments using main effects of different components and their percent contribution towards the MnP production. Total 31 components were considered in this study at temperature 30°C and incubation period of 5 days, in which Galactose, Malt extract, KH2 PO4 , NH4 H2 PO4 , CaCO3 , Tween80, Tartaric acid and sodium acetate were found to be significant components for MnP production. Further, response surface methodology was employed to optimize the media containing screened components along with temperature, pH and incubation days. The optimized medium contained 1.5% Galactose, 0.06%Malt extract, 0.02%KH2 PO4, 0.15%NH4 H2 PO4 , 0.003%CaCO3, 0.8%Tween80,0.005% MnSO4,0.88%Tartaric acid and 3% sodium acetate at temperature 31°C and pH 5.2 incubated for 5 days increased MnP productivity by 43 folds (43.2±1.29 U mL-1)when compared to un-optimized media (1.1±0.087 U mL-1). MnP produced was tested for lignolytic effects on different crop residues. Digestibility studies of different crop residues treated with crude MnP rich extracts indicated that a significant decrease in the percentage value of lignin and increase in in-vitro digestibility matter (at confidence interval 95%) when compared with untreated straws.

Manganese peroxidase (MnP), a crucial enzyme in biodegradation of lignin, is synthesized by most white rot fungi. To obtain novel enzymes with superior biodegradation potential, MnP-producing wild isolates were evaluated for their ability to degrade recalcitrant azo dyes, sulfonephthalein dyes, and kraft lignin. Of 30 wild isolates screened, 18 tested positive for lignin modifying enzymes (LMEs). Thirteen of these isolates were positive for both laccase and MnP, whereas four produced only laccase, and one produced lignin peroxidase alone. The isolates were identified as Clitopilus scyphoides MH172162 (AGUM004), Ganoderma rasinaceum MH172163 (AGUM007), and three Schizophyllum species: MH172164, MH172165, and MH172166 (KONA001, AGUM0011, and AGUM021). The Fourier-transform infrared spectroscopy (FTIR) analysis of dye degradation and kraft lignin samples with AGUM004 and AGUM007 revealed biotransformation. The former could not completely degrade Reactive Black 5 and bromocresol green, but it could completely (100%) decolorize bromophenyl blue, bromothymol blue, and Remazol brilliant blue R. The latter efficiently degraded almost all tested dyes. Both degraded kraft lignin. The screened hyper MnP-producing wild AGUM004 and AGUM007 were shown to be potential dye degraders in addition to having lignin degrading abilities.