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The growth of lymphocytic leukemia L1210 strains in mice was inhibited by phenylalanine ammonia-lyase (PAL) from Ming mung bean.The isolation, purification and properties of phenylalanine ammonia-lyase in Ming mung bean was studied by 35% and 65% saturation of ammonium sulfate grade deposition,and ion exchange chromatography.The results showed that purification multiple was 6.982 9, protein yield and PAL yield were 4.65% and 32.45%, respectively.SDS-PAGE revealed a single stained protein band which corresponded to a subunit weight of 76 kD.The optimal pH range of PAL in borax-boric acid buffer was from 7.6 to 9.0, and the optimal pH values were 8.0 and 8.6.PAL could not bear alkali and acid, especially the former.The optimal temperature range of PAL was from 35 ℃ to 45 ℃, and the optimal temperature was 40 ℃.Its activity was easy blunt above 70 ℃.There were two Km values, one was 6.94×10-5 mol/L, and the other was 1.23×10-4 mol/L.L-tyrosine had inhibiting effects on PAL and the inhibitory effects changed with different inhibitors.L-cystine had no effect on the activity of the PAL.The results could provide theoretical reference for further studying and developing PAL from Ming mung bean.