Increase in Colony-Forming Unit of Bacterial Communities in Aquatic Environments by Supplementation with Sodium Pyruvate

Abstract

It has been reported that higher plate counts for bacterial communities in river epilithon were yielded on agar plates by supplementation with sodium pyruvate, compared to the counts without supplementation.To support the credibility of this phenomenon, studies were conducted regarding the bacterial communities in several aquatic environments.Consequently, degrees of the ratio of colony-forming unit(CFU)on agar plates supplemented with sodium pyruvate to that without supplementation were grouped into two categories:a 2 to 3 magnitude group and a 5 to 6 magnitude one.According to cluster analysis of the water quality, higher degrees of the ratio were observed at environments that had a DOC concentration around 1ppm and had a low NO₃^- concentration.The compositions of the abundantly-appearing bacterial colonies were suggested to be different from that of those appearing on the agar plates without supplementation of sodium pyruvate.