Influence of an extract of Juglans regia on the growth of Escherichia coli, on the electrophoretic profile of plasmid DNA and on the radiolabeling of blood constituents

Abstract

The aim of this work was to study the influence of a walnut (Juglans regia) extract on the growth of Escherichia coli (E. coli) AB1157, on the plasmid DNA topology and on the labeling of blood constituents with technetium-99m (99mTc). An E. coli AB1157 culture, in stationary phase, was incubated with walnut and the growth of the culture was evaluated by optical density at 600 nm for 7 hours. Plasmid DNA samples were incubated with SnCl2 in presence or absence of walnut for 40 minutes, 0.8% agarose gel electrophoresis was performed, the gel was stained and the plasmid topological forms were visualized. Blood samples from Wistar rats were incubated with walnut extract and an assay of labeling of blood constituents with technetium-99m (99mTc) was performed. Blood cells and plasma were separated. The radioactivity in each fraction was counted and percentage of incorporated radioactivity (%ATI) was determined. The results presented an inhibitory action of the growth of the E. coli AB1157 culture, no protective action of the walnut extract in plasmid DNA treated with SnCl2. Moreover, walnut was also not capable to induce modifications in the DNA mobility in agarose gel but walnut was capable to decrease the distribution of 99mTc on the blood cell compartment. In conclusion, our experimental data suggest that in the walnut extract has substances with an effect on the growth of E. coli culture, a potential action to increase the SnCl2 effect on plasmid DNA and also is capable to alter the distribution of 99mTc on the blood cell compartment probably due to redoxi properties.