Thesis (M.Sc.)--Chulalongkorn University, 2005

This study focuses on the removal of phenolic compounds by peroxidase derived from agricultural waste, The phenols studied are phenol, o-cresol, n-cresol, p-cresol, 2-chlorophenol, 3-chlorophenol, 4-chlorphenol, catechcol, resorcinol, hydroquinone, 1-naphthol and 2-naphthol. The extraction of crude POD from sweet potato with phosphate buffer exhibited the highest activity and removal efficiency. The optimum conditions for removal of phenol was at 30 ํC, 100 min, pH 7,20 ppm of phenol, 0.5% w/w of H[subscript 2]O[subscript 2], 10 units/mL of crude POD, 20 ppm of PEG-6000 and phosphate buffer as solvent. Rate of conversion of phenol under this condition was 1.045 [micromol] per h. The optimum condition for removal of phenols was at 30 ํC, 100 min, pH 7,20 ppm of phenols, 1.0% w/w of H[subscript 2]O[subscript 2], 4 units/mL of crude POD and phosphate buffer as solvent. The product from the removal of phenol by POD is polymer consisted of 2-phenoxy-biphenyl, 1,1'-biphenyl-2,2'-diol and 4-phenoxy-biphenyl while that derived from the removal of o-cresol by POD is 2,2'-ethylenediphenol.