Properties Of Porphobilinogen Deaminase And Its Relationship With The Garlic Greening

The research used the pizhou garlic bulb as the raw material to study the variation of the content of PBG, the activity of PBGD and the strength of garlic greening as the storage time of garlic prolong. The study explored the relationship between PBG, PBGD and the garlic greening. The isolation and purification of the PBGD conducted with DEAE-Sepharose FF ion-exchange chromatography, Phenyl Sepharose CL-4B hydrophobic interaction chromatography, Sephadex G-200gel chromatography were also operated in this research. The study determined the dynamics properties and influence factors of PBGD as well. In order to find the specific measure to control the strength of garlic greening, the influence of the extractive of tea, the onion juice and the extractive of ginkgo leaf on garlic greening were researched in this study. The main results were as follow:1. The research measured the strength of garlic greening, the content of PBG and the activity of PBGD of the garlic bulb stored at4℃and room temperature per10days. The results showed that:the general tendency of garlic greening was enhanced, as the tendency of4℃was obvious and the room temperature was slow. Both of the greening at4℃and room temperature were declined at the later period of the storage because of the consume of the nutrient substance. The strength of garlic greening of4℃was always higher than the one of room temperature at the same conditions. The content of PBG has the same tendency with the strength of garlic greening in the same condition. It could conclude that they had some relevance. The measurement results of the activity of PBGD and the content of PBG were consistent. They showed that the activity of PBGD and the garlic greening had some relevance, the higher of the former, the lower of the content of PBG, the weaker of the garlic greening.2. After the isolation and purification of the PBGD conducted with DEAE-Sepharose FF ion-exchange chromatography, Phenyl Sepharose CL-4B hydrophobic interaction chromatography, Sephadex G-200gel chromatography, the research studied the dynamics properties and influence factors of it, such as the Km, temperature, pH, concentration of substrate, metal ion etc. The results showed that:the optimum temperature of PBGD was37℃, the optimum pH was8.0, Al3+can activate the PBGD prominently while K+and Na+had no influence on it,the maximum reaction velocity Vmax of PBGD was357.1μg/hmg protein,Km was0.68μg/mL. 3. The study explored the influence of the extractive of tea and ginkgo leaf with different concentrations on garlic greening. The effect of the onion juice with different volume on garlic greening was also conducted in this study. The results showed that all of the three materials above had restrain effect on garlic greening, and the effects of the extractive of tea and the ginkgo leaf were better than that of the onion juice.