Volume 8 (2010) Issue 4 Pages 421-427
The relation between the denitrification rate and quinone compositions of the microorganisms in the water treatment apparatus for paddy drainage was evaluated. Q-8 content, the highest ubiquinone, had the strongest correlation coefficient between the denitrification rate (DNR) and the detected ubiquinone. MK-7 had the strongest correlation with DNR among the detected menaquinones. From the results of principal component analysis for DNR using quinone content as the variables, the first principal components were Q-8 and Q-9, and the second principal component was MK-8. Q-8, Q-9, MK-7 and MK-8 containing bacteria strongly contribute to DNR in the water treatment apparatus and around the paddy environment.