Bactericidal effect of supercritical N₂O on Staphylococcus aureus and Escherichia coli.

The aim of this study is to investigate the bactericidal effect of supercritical nitrous oxide (SC N(2)O) on both typical Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli while varying the operating conditions including the suspending medium (nutrient broth, phosphate buffered saline, phosphate buffer, phosphate buffer containing oleic acid), pressure, temperature, mixing intensity, and working volume (the ratio of the sample volume to the reactor volume). Approximately 7 log of both S. aureus and E.

Characterization of the depth-related changes in the microbial communities in Lake Hovsgol sediment by 16S rRNA gene-based approaches.

The undisturbed sediment of Lake Hovsgol (Mongolia) is scientifically important because it represents a record of the environmental changes that took place between the Holocene (the present age) and Pleistocene (the last ice age; 12,000 14C years before present day). Here, we investigated how the current microbial communities change as the depth increases by PCR-denaturing gradient gel electrophoresis (DGGE) analysis of the 16S rRNA genes of the microbial communities. The microbial diversity, as estimated by the Shannon index, decreased as the depth increased.