Inactivation of spores by electric arcs

Background

In the context of spore contamination involved in bio-terrorism and food preservation, the development of new techniques for spore inactivation is an important challenge.

Results

Here, a successful application of electric arc discharges resulting in spore death was reported. Two types of electric arcs were compared, different with respect to their durations. The discharges with 0.5 μs duration induced a small inactivation area of 0.6 % of surface treated around their point of entry into the sample, while those with 20 μs duration induced a much larger inactivation area from 7 to 55 % of surface treated roughly proportional to the number of discharges delivered. In particular, 50 discharges of 20 μs duration induced inactivation in more than 55% of surface treated at an inactivation rate above 3.6 log10.

Conclusions

These results are promising and warrant developing electric arcing as a novel method for spore inactivation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12866-016-0764-x) contains supplementary material, which is available to authorized users.

Electroporation-based applications in biotechnology

Electroporation is already an established technique in several areas of medicine, but many of its biotechnological applications have only started to emerge; we review here some of the most promising. We outline electroporation as a phenomenon and then proceed to applications, first outlining the best established - the use of reversible electroporation for heritable genetic modification of microorganisms (electrotransformation), and then explore recent advances in applying electroporation for inactivation of microorganisms, extraction of biomolecules, and fast drying of biomass. Although these applications often aim to upscale to the industrial and/or clinical level, we also outline some important chip-scale applications of electroporation. We conclude our review with a discussion of the main challenges and future perspectives.