The influence of four kinds of Schiff bases on a strain of Escherichia coli was studied by microcalorimetry. Differences in their capabilities of suppressing the metabolism of this bacterium were observed. The results...The influence of four kinds of Schiff bases on a strain of Escherichia coli was studied by microcalorimetry. Differences in their capabilities of suppressing the metabolism of this bacterium were observed. The results show that the extent and duration of the inhibitory effect on the metabolism as judged from the multiplication rate constant, k , varies with different Schiff bases. The multiplication rate constant k , of Escherichia coli (in log phase) in the presence of Mo salicylioaldehyde thiadizole, Mo piperonaldehyde thiosemicarbazone and Mo 3 methoxy salicylicaldehyde thiadizole decreases with the increase of concentrations of compounds c , and the relationships between k and c , maximum heat production rate p m and c , peak time of growth curves t p and c are of linearity. For Mo 6 nitro pieronalde thiosemicarbazone, the multiplication rate constant is constant irrespective of variation in concentration. The sequence of antibiotic activity of Schiff base is : Mo salicylioaldehyde thiadizole>Mo 3 methoxy salicylicaldehyde thiadizole>Mo piperonaldehyde thiosemicarbazone>6 nitro pieronalde thiosemicarbazone.展开更多
文摘The influence of four kinds of Schiff bases on a strain of Escherichia coli was studied by microcalorimetry. Differences in their capabilities of suppressing the metabolism of this bacterium were observed. The results show that the extent and duration of the inhibitory effect on the metabolism as judged from the multiplication rate constant, k , varies with different Schiff bases. The multiplication rate constant k , of Escherichia coli (in log phase) in the presence of Mo salicylioaldehyde thiadizole, Mo piperonaldehyde thiosemicarbazone and Mo 3 methoxy salicylicaldehyde thiadizole decreases with the increase of concentrations of compounds c , and the relationships between k and c , maximum heat production rate p m and c , peak time of growth curves t p and c are of linearity. For Mo 6 nitro pieronalde thiosemicarbazone, the multiplication rate constant is constant irrespective of variation in concentration. The sequence of antibiotic activity of Schiff base is : Mo salicylioaldehyde thiadizole>Mo 3 methoxy salicylicaldehyde thiadizole>Mo piperonaldehyde thiosemicarbazone>6 nitro pieronalde thiosemicarbazone.
