The Combination of Plasma-Processed Air (PPA) and Plasma-Treated Water (PTW) Causes Synergistic Inactivation of Candida albicans SC5314

Uta Schnabel,Kateryna Yarova,Björn Zessin,Jörg Stachowiak,Jörg Ehlbeck

doi:10.3390/app10093303

Uta Schnabel, Kateryna Yarova + Show 3 more

Open Access

https://doi.org/10.3390/app10093303

Copy DOI

Abstract

Microwave-induced plasma was used for the generation of plasma-processed air (PPA) and plasma-treated water (PTW). By this way, the plasma was able to functionalize the compressed air and the used water to antimicrobial effective agents. Their fungicidal effects by single and combined application were investigated on Candida albicans strain SC5314. The monoculture of C. albicans was cultivated on specimens with polymeric surface structures (PE-stripes). The additive as well as the synergistic fungicidal potential of PPA and PTW was investigated by different process windows of plasma exposure time (5–50 s) and sample treatment time with PPA/PTW (1–5 min). For a single PTW or PPA treatment, an increase in the reduction factor with the indicated treatment time was observed (maximum reduction factor of 1.1 and 1.6, respectively). In comparison, the combined application of PTW and then PPA resulted in antagonistic, additive and synergistic effects, depending on the combination. An application of the synergistically acting processes of PTW for cleaning and PPA for drying can be an innovative alternative to the sanitary processes currently used in production plants.

Highlights

The sources of contamination along the entire value chain of fresh and fresh-cut products are numerous and diverse
This depends on the procedures themselves
The plasma-treated water (PTW) used in our experiments showed a strong acidification, which could be a consequence of the radicals

Summary

Introduction

The sources of contamination along the entire value chain of fresh and fresh-cut products are numerous and diverse (raw materials, processing tools, surfaces in contact with food, lack of hygiene among employees). A contaminated product will most likely lead to a negative impact along the entire production chain. Non-thermal plasmas (non-equilibrium plasmas) are plasmas in which the cooling of ions and uncharged particles is more effective than the transfer of energy from energetically excited electrons to the latter particles. This has the effect that the gaseous environment does not heat up, which is usually the case in thermal plasmas [1]. Their high antimicrobial potential in combination with a non-thermal application is very advantageous [2]

Methods

Results

Conclusion