Synergistic Effects of Anionic Surfactant and 0.30 T Static Magnetic Field On the Activity and Structure of Catalase

In this research work, bovine liver catalase was modified by anionic surfactant sodium dodecyl sulphate(SDS) and influenced by 0.30 T static magnetic field(SMF). It was interesting to note that the activity of catalase appeared more stable after treatment by synergistic action of SMF and SDS. Catalase(CAT) lost about 35% of the initial activity after 12 h, while the CAT-SDS, CAT-SMF, and CAT-SDS-SMF retained over 69%, 80%, and 86% of their initial activities, respectively. Temperature profiles showed that 30 °C was the ideal temperature for active domain of catalase in all the research groups, and there was no significant loss of activity in the CAT-SDS-SMF for the thermal stability, while about 65.8% of the maximal activity remained at 70 °C. The activity remained stable after incubation at temperatures of 30-70 °C, while others appeared unstable without treatment by the synergistic action of SMF and SDS. Kinetics parameters were calculated to follow the Michaelis-Menten model, the Km and Vm values of CAT-SDS were 600 times and 5 times higher than those of other groups, respectively. However, the synergistic action of SMF and SDS on catalase integrated both advantages. The synergistic effect not only promised good catalytic efficiency, but also maintained a favorable maximum velocity, while the Km value of CAT-SDS-SMF was about 40 times higher than that of the control group. Besides these results, there were no significant differences in kinetics parameters between CAT and CAT-SMF. In addition, the circular dichroism spectra and fluorescence spectra were also investigated. The secondary structure of catalase was changed by the synergistic action of SMF and SDS.