Development of analytical technique of change in microbial population for remediation in the polluted soil

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Microorganisms perform an important role for remediation in various polluted environment. To optimize the activity of microorganisms on contaminated sites, the ability of microorganisms must be clarified on the optimal condition for decomposing bacteria. The behavior of specific bacteria and microbial population should be clarified. The objective of this study is to develop the analytical technique for clarification of the behavior of specific bacteria and microbial community structure in natural waters and soils.The direct application of molecular genetic methods on soil bacteria is often prevented by the large amounts of soil colloids. Hence, an extraction of bacteria cells from soil is usually required before analysis of their genetic material. For this reason, the selection of a suitable extractant was investigated. The extraction efficiency of bacteria and the representation of the microbial population extracted from soil by using quinone-profiling method were evaluated in the exp … More eriments. The fraction of the respiratory active cell extracted from soil was also evaluated by using CTC (5-cyano-2, 3-ditolyl tetorazolium chloride) reduction and plate count techniques. 1/15M Na-phosphate, 0.03M Na-oxalate and 0.03M Na-pyrophosphate were used as the extractants. The extraction efficiency of bacteria was defined as the ratio of quinone contents in the extract to that in soil. Compared with other two extractants, Na-pyrophosphate demonstrated the highest extraction efficiency of bacteria and respiratory active cells in the extract from soil. In addition, cell numbers of Proteobacteria, and γ-subclass in extraction with Na- pyrophosphate was measured by FISH. Almost all bacteria of Proteobacteria α, β and γ-subclass contain UQ-10, UQ-8, UQ-9, respectively. The experimental results showed that there was very similar relationship between ratio of Proteobacteria β, γ to α-subclasses and ratio of UQ-8, UQ-9 to UQ-10, respectively. It indicates that specific bacteria in soil sample can be quantified by FISH technique.In addition, the quinone profile and CTC reduction can be used to clarify the effect of particle size of sediment on microbial-ecosystem and water purification using an experimental facility of the tidal flat, and to analyze microbial community structure in sediment. Less