Cu(Ⅱ)-salicylate complex has been synthesized and its crystal structure has been determined. The activity of SOD and Cu(Ⅱ)-complex catalyzing dismutation of superoxide radical (O2^-.) has been studied by improved NBT method in phosphate buffer (pH=7.8), micellar solution and lamellar liquid crystals(LLC) fomed from surfactants CTAB or TX-100. The X-ray diffraction indicates that the Cu(Ⅱ)- complex has a formula Cu2(HSal)4EtOH·H2O and similar structure to SOD active site. It was proposed from RPE spectra that the reaction mechanism of Cu(Ⅱ)-complex catalyzing O2^-. dismutation was similar to that of the proposed dismutation reaction catalyzed by SOD. The results obtained by improved NBT method show the inhibition by SOD or Cu(Ⅱ)-salicylate complex of NBT reduction in organized assemblies of surfactants is weaker than in aqueous solution. The order of inhibition is as follows: in phosphate buffer > in CTAB micelle > in CTAB lamellar liquid crystal; in nonionic TX-100 organized assemblies > in cationic CTAB organized assemblies. The resuts can be explained by catalytic effect of micelle, high viscosity of LLC and decrease of α-helical content in SOD in organized assembly of surfactants. The effect of PrCl3 on SOD-like activity of Cu(Ⅱ)- complex in phosphate buffer (pH=7.8) has been determined. The results indicate that PrCl3 can inhibit the reduction of NBT by itself. The cooperativity of PrCl3 and Cu(Ⅱ)-complex has been also obtained, however, the reaction mechanism of PrCl3 is different from that of SOD and Cu(Ⅱ)-complex.

Key words: SURFACTANTS, MICROENVIRONMENTAL EFFECTS, SALICYLIC ACID P, COPPER COMPLEX, ACTIVITY, RARE EARTH COMPOUNDS, PRASEODYMIUM COMPOUNDS, SUPEROXIDE DISMUTASE