The Production And Functions Of Endogenous Hydrogen Peroxide In Escherichia Coli And Its Effect On The Quality Of Agricultural Products Storage

In this research, conductivity method, malondialdehyde (MDA) method, fluorescence method and histochemical method were used to investigate the effects of the generation mechanism, and function of hydrogen peroxide (H2O2), and its impact on the quality of agricultural products.Experimental results showed that conductivity value of E. coli mutants LC74was higher than MG1655. It is likely that H2O2had damage to the cells, and reduced the resistance ability to antibiotics injure of the bacteria. It is showed that gentamycin can actually increase the amount of H2O2accumulated around E. coli cell, protoplast and mesosome. What’s more, the excretion of mesosome can increase the H2O2accumulated around protoplast no matter whether the protoplast had been injured or not.Combined with the results of the MDA and histochemical methods, H2O2accumulated around the protoplast was increased while the MDA increased at the same time. As for the mesosome, H2O2accumulation around the mesosome was opposite to MDA. Speculation that H2O2around the protoplast may have damage to protoplast, H2O2around the mesosome has a protective effect.Amino sugars antibiotics (gentamycin, amikacin) can effectively influence the H2O2content, conductivity and mesosome protein of this supernatant. But there still has not find the relation among H2O2, mesosome protein and antibiotics.Through simulation the infection of bacteria on the storage of agricultural produce, the experiments result showed1mg of exogenous H2O2resulted in death or sublethal damage to bananas, which led to a declining of conductivity and browning degree, and a growing of catalase (CAT) activity. However, to the banana peel,1mg exogenous H2O2increased its conductivity and browning degree, and activity of CAT decreased, while4mg exogenous H2O2had a death or sublethal damage. Thus showed that as to different action sites, the role of the same concentration of exogenous H2O2is different. As to the same action site, a low concentration of exogenous H2O2can promotes browning, and a high concentration of exogenous H2O2can delay the browning and decay.Through the study of the role of H2O2in cell damage, it may help us find out a new strategie by control the level of reactive oxygen species to improve the product quality of agricultural products in the process of storage and processing of agricultural products.