Antimicrobial activity of sodium citrate against Streptococcus pneumoniae and several oral bacteria.
OBJECTIVE
The aim of this study is to assess the antibacterial activity of sodium citrate against Streptococcus pneumoniae and several oral bacteria.


RESULTS
The antibacterial activity was determined by broth microdilution method. The results showed that although Enterocuccus faecium OB7084 and Klebsiella pneumoniae OB7088 had high tolerance to sodium citrate, several oral bacteria including Fusobacterium nucleatum JCM8532(T) , Streptococcus mutans JCM5705(T) and Strep. pneumoniae NBRC102642(T) were susceptible. Furthermore, the bactericidal activity of sodium citrate against Strep. pneumoniae NBRC102642(T) was not influenced by pH in the range of 5·0-8·0, whereas that of sodium lactate was weakened at neutral or weak alkaline pH. When Strep. pneumoniae NBRC102642(T) was treated with sodium citrate for 2 h, many burst cells were observed. However, addition of MgCl(2) or CaCl(2) to an assay medium weakened the antimicrobial activity although ZnCl(2) or MnCl(2) did not influence.


CONCLUSIONS
Independent of pH, sodium citrate inhibited the growth of oral bacteria, which suggests that the mechanism is different from that of sodium lactate.


CONCLUSIONS
The results presented in this study would be available for understanding the antimicrobial property of sodium citrate.
Nagaoka
S
S
Food Science Institute, Meiji Dairies Corporation, Odawara, Japan.
Murata
S
S
Kimura
K
K
Mori
T
T
Hojo
K
K
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D001424:Bacterial Infections / Q000382:microbiology; D002951:Citrates / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D009059:Mouth Diseases / Q000382:microbiology*; D011008:Pneumococcal Infections / Q000382:microbiology*; D000077559:Sodium Citrate; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000302:isolation & purification
D000900:Anti-Bacterial Agents; D002951:Citrates; D000077559:Sodium Citrate