Abstract: | This study investigated the extraction of 5'-phosphodiesterase from malt root and the degradation of nucleic acids by this enzyme.The extraction used grade precipitation with ammonium sulfate and enzy-matic hydrolysis.Samples were assayed using the modified Bradford method and high performance liquid chromatography.The results show that 5'-phosphodiesterase is isolated by grade precipitation with 30% and 80% saturation of ammonium sulfate and can be utilized to degrade deoxydbonucleic acid.The hydrolysate has four kinds of deoxynucleotides: 5'-dCMP,5'-dTMP,5'-dAMP,and 5'-dGMP.The optimum reaction tem-perature is 70℃,and the optimum pH is 5.5-6.0 for the reaction.The percentage of deoxynucleotides indi-ceted by the China Pharmacopoeia (2000 edition) in the product is over 70%.The extraction of 5'-phosphodiesterase from malt root is shown to be possible and economical.Products from the enzymatic hydrolysate of DNA meet the pharmacopoeia. |