Effects of pulse electric fields to the pathogenic bacteria

Abstract

The pulsed power technology is gaining ground on applications to biological field such as sterilization with pulse electric fields or discharges and induction of the apoptosis with pulse electric fields. Under the circumstances, the pulse electric fields clearly have some influence on organism. To figure out the influence and mechanism, we conducted an experiment. The pulse electric fields were applied to the pathogenic bacteria, and manifestation of RNAs which affected pathogenicity was examined. A system was developed to apply the pulsed electric fields to bacteria. The pulsed power generator, which consists of a Blumlein-type pulse forming network (B-PFN), outputs pulses with width of 100 ns in the case of 5 L-C stages. The electrodes chamber was filled with the solution (2 ml) with bacteria. The separation of the electrodes was 5 mm and approximately uniform electric field was applied to the solution. The manifestation of RNAs was analyzed with the method of polymerase chain reaction, PCR Vibrio parahaemolyticus (RIMD 2210633) was selected to examine. The manifestations of RNAs as VP1699, VP1680, VPA1321, VPA1327, VPA1346, TDH, and RNA16S were examined with the PCR method. Although RNA16S does not become an index for pathogenicity, evaluation of RNA16S implies a survival ratio of the bacteria. The initial density of bacteria solution was regulated to be 109 /ml. The peak voltage was approximately 6, 12 kV and the number of applied pulses was 1000 for each sample. The tendency of increase in manifestation was found by the application of pulse electric fields for VP1699 and VP1680 with relation of TTSS(1).