Shinya Kozaki

Degradation of lignin compounds by bacteria from termite guts

By incubating bacteria from the gut of the termite, Nasutitermes takasagoensis, in a culture medium containing a ligninic compound, direct evidence that lignin-biodegradation occurs in the gut of termites was obtained. The bacteria were capable of degrading ligninic compounds. 28% of dealkalized lignin was degraded and lignin dimer compounds, which have a linkage proper to lignin, such as β-O-4, β-1, phenylcoumarane and biphenyl bonds, were degraded by 60 % to 95 %.

Bioaugmentation of TCE-Contaminated Soil with Inducer-Free Microbes

Environmental pollution is a world-wide problem since these pollutants cause serious disease not only for human beings but also for other plants and animals. Trichlo-roethylene (TCE) is a typical pollutant in soil and groundwater, and its concentration is strictly regulated since many people are using groundwater as drinking water. TCE is very stable in the environment, and soil vapor extraction (SVE) is frequently used for the removal of TCE. However, the removal efficiency in SVE decreases with low concentrations of TCE. Charcoal adsorption and photocatalytic degradation are other approaches to detoxify soil and groundwater, but in situ treatment is needed for cost-effective remediation. Bioremediation for TCE-contaminated soil is an attractive approach for in situ treatment, and many microbes which can decompose TCE have been reported.