Novel method for enhancing the destruction of environmental pollutants by the combination of multiple plasma discharges.

A novel, multistage, dielectric, packed-bed, plasma reactor has been developed and is used to efficiently destroy environmental pollutants, such as volatile organic compounds (VOCs). A three cell plasma reactor, operated at ambient pressure and low temperatures, is found to be an effective technology for complete VOC remediation in air. The combination of plasma cells in series can significantly improve the efficiency of VOC decomposition, but the combined destruction rate is not simply an additive effect, there is a synergistic enhancement related to the effect on the plasma chemistry of sequential processing in the three cells.

pH-regulated expression of the acid and alkaline extracellular proteases of Yarrowia lipolytica.

The pH-regulated expression of the acid (AXP) and alkaline (AEP) extracellular proteases of the yeast Yarrowia lipolytica 148 was analysed. Expression in batch and continuous cultures was determined at the mRNA level by Northern blotting, and at the enzyme level by enzyme assays and Western blotting. Culture pH regulated AEP and AXP expression predominantly at the level of mRNA content.