الفهرس 
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Abstract
Enzyme activity of MnP was assayed in extracts from Trichoderma harzianum, Acremonium terricola, Acremonium sp., Trichosporon sp., Geotrichum candidum, Penicillium sp., Trichoderma koningii and Scopulariopsis brevicaulis.
- Trichoderma harzianum expressed the highest activity therefore it was chosen as the experimental fungus.
- Trichoderma harzianum was identified morphologically and confirmed by molecular characterization.
- The production of the enzyme by Trichoderma harzianum was optimized.
- The best carbon source was sucrose.
- The best nitrogen source was yeast extract.
- The optimum incubation temperature for the enzyme production was 30 oC and the optimum pH for the production was 5.0.
- MnP was purified using ammonium sulphate, precipitation, DEAE-Cellulose and Sephadex G-200.
- The final specific activity was 208.5 units mg-1 protein and the purification fold was 224.2. The yield was 48.3%.
- The SDS-PAGE reveal one band for MnP which indicating the homogeneity of the enzyme preparation.
- The optimum incubation time on MnP activity was 40 min.
- Th optimal pH and the optimal temperature for the MnP were 5.0 and 45 oC respectively.
- The activation energy was 14.7 KJmol-1.
- Continuous increase in the enzyme activity with increasing MnSO4 concentration.
- The values of Vmax and Km were 109.9 units mg-1 protein and 1.2 mM, respectively.
- Cu2+ was the best activator at 5 mM followed by Ca2+ as activators. The rest of the various cations were inhibitors.
- Na2SO4 was stimulator at both 1 and 5 mM, while the other remaining anions were inhibitors.
- Dansyl chloride (DnsCl), butanedione (BD), N-acetylimidazole (NAI), N-bromosuccinimide (NBS) and N-ethylmaleimide (NEM)
Summary
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were inhibitors at the various concentrations tested and IC50 values were 8.6 mM, 4.8 mM, 1.9 mM, 8 mM and 1.4 mM, respectively.
- Glycine as amino acid was activator up to 0.6 mM.
- GA3 and Cyt were stimulators whereas ABA was inhibitor.
- Succinic anhydride and maleic anhydride were inhibitors.
- MnP was immobilized on luffa, ceramic, Ca alginate and chitosan. The chitosan was the best support.
- MnP was inhibited by chelating agents such as phenanthroline, α,α-dipyridyl and EGTA.
- Thioglycolate, reduced glutathione activated the enzyme at various concentrations (0.2, 0.4, 0.6, 0.8 and 1.0 mM).
- The enzyme showed appreciable thermostability at 50oC and the thermostability was increased in presence of trehalose, bovine serum albumin, glycol chitosan and dextrose.
- The application of the purified enzyme for dyes removing suggested that the enzyme is promising candidate for bioremediation process.
- Also, the application of the purified enzyme for phenol removing indicated that the enzyme was successful in this bioremediation process.