Determination of Pyrazinamide. V

On the Decomposition of Pyrazinamide by Escherichia coli communior and Streptococcus faecalis R

Abstract

Decomposition of pyrazinamide by enteric bacteria was examined and it was found that while this compound is easily decomposed to pyrazinoic acid by Escherichia coli communior and Streptococcus faecalis R, it is not decomposed by Lactobacillus acidophilus. Further examinations were made on the relationship between the rate of decomposition and pH, and on velocity of decomposition and it was found that decomposition by E. coli is accelerated the most at around pH 5.0 but to a fair extent in neutral to slightly alkaline range and that the decomposition is almost complete in 5 hours at pH 5-9 range when 10mg./cc. of dried bacteria is used for 300γ/cc. of pyrazinamide. The decomposition by S. faecalis is accelerated the most at around pH 7.0 and 300γ/cc. of pyrazinamide is decomposed almost completely with 10mg./cc. of dried bacteria in 7 hours.