Effects of low electric current (LEC) treatment on pure bacterial cultures

Abstract

Aims: This research focused on the effects of low electric current (LEC) on the cell viability and metabolic activity of Escherichia coli and Bacillus cereus. Methods and Results: Different LEC intensities at fixed amperage were applied, employing either graphite or copper electrode pairs, and the effects were determined by conventional cultural methods and bioindicators. On E. coli, the LEC with graphite electrodes at 5 and 10 mA led to no significant variation, but at 20 and 40 mA there was increasing inhibition of both the enzymatic activities and growth, and a reduction in ATP content. On B. cereus, similar experiments at the lower amperages did not have any inhibitor effects, however, the 40 mA current stimulated growth, ATP content and some enzymatic activities. The LEC treatment using copper electrodes caused, already at 5 mA, inhibition of bacterial growth and metabolic and enzymatic activities in both E. coli and B. cereus. Conclusions: On the basis of the obtained results using different amperages and electrodes, we can conclude that E. coli seem to be more sensitive compared with B. cereus. Significance and Impact of the Study: The study increases the knowledge on LEC treatment effects on the pure bacterial cultures.

Microbial Growth Inhibition by Alternating Electric Fields

“…The use of electric current as a bacterial growth inhibitor was reported more than 40 years ago (24), with many subsequent reports over the years (27,30). Most of the literature on the subject deals with enhancement of the efficacy of antibiot- ics against microbial biofilms by the application of weak DC currents, a phenomenon termed "the bioelectric effect" by Costerton et al (5).…”

Phenol Degradation by Suspended Biomass in Aerobic/Anaerobic Electrochemical Reactor

“…The positive or negative effects of DC mainly depend on current intensity, duration of treatment, and microbial type. For example, Valle et al (2007) investigated the electrolytic stimulation of Escherichia coli and Bacillus cereus and found that the application of 40 mA inhibited the cell growth and metabolic activities of E. coli, but enhanced that of B. cereus. These phenomena may depend on at least two parameters: current intensity and microorganism type.…”

“…Thus, an optimum current intensity may stimulate biodegradation of organic components, but lower or higher than it will have no impact or negative effects on pollutant biodegradation. In addition, the responses of different microorganisms (e.g., cell growth, enzymatic activity, and adenosine triphosphate (ATP) content) to the electrical stimulation are varied greatly (Valle et al 2007). Moreover, the extreme pH changes resulted from the water electrolysis reactions in the vicinity of the electrodes and high voltage values could inhibit the growth and activity of the microbes and lead to their death (She et al 2006;Lear et al 2004).…”

The Dental Architect

“…Again, important for our purposes is the fact that dental surgery had recognized, and does today, this potential "electro-chemical" issue and its actions upon our implants, screw posts, other metals like amalgams, and crown and bridge metal restoration and its effect upon the oral cavity [2,3]. Related to this issue we present our Case Study.…”

“…We offer patients in our practice neurological assessments for various facial non-specific pain by measuring the electrical dc output of metals with a potentiometer (multi-meter: measuring mV=millivolts, and uA=micro -amperage [1][2][3] (EAV assessment and acupuncture may be useful tools also. ).…”