## 3 Results and Discussion
### Bactericidal Efficacy of Tb-PAW on Different Microorganisms
Furthermore, we have shown that the treatment of anaerobes with Tb-PAW also leads to different inactivations. Our findings depicting an increased impact of Tb-PAW on anaerobic bacteria is supported by the study of [PERSON] et al. [34]. They also found that aerobic bacteria, such as _Streptococcus mutans_, are less sensitive than anaerobic bacteria when exposed to comparable concentrations of different ROS species. A strong interdependency of antibacterial efficacy of the applied Tb-PAW's and bacteria species is apparent. To date, the exact mode of action of PAW has not been fully elucidated. As described by [PERSON] et al. [35] the effect of other ROS and RNS produced in PTW besides NO3\({}^{-}\) is not well understood. According to [PERSON] et al. [36], plasma-activated chemical solutions (PACS) containing H+, NO2\({}^{-}\) and H2O2 and especially their conversion to peroxynitrite, play a key role in microbial decontamination. [PERSON] et al. [25], who emphasized the role of peroxynitrite in their work, also supported this statement. However, other authors have noted that H2O2, hydroxyl radicals (\(\bullet\)OH), and ozone (O3) for example, play important roles ([PERSON] et al. [37]). Thus, further research is necessary to understand the mode of action of PAW. The TRIS-buffer used in the present study caused the ph-value of the Tb-PAW to be neutral, giving the opportunity for their in situ application on open wounds and skin of living animals. Some studies compared the results between PAW and plasma-activated buffer in relation to their acidity and figured a lower pH-value would increase the inactivation rate [16; 17; 38]. Consequently, we decided on the one hand to buffer the PAL, on the other hand to adjust the control solution to the pH-value of the Tb-PAW, which was also associated with high inactivations. Tb-PAW Inactivation Ability of E. coli, F. necrophorum and P. levii under the Influence of Bovine Serum Albumin  
In the present study the impact of bovine serum albumin (BSA) on the antimicrobial capacities of Tb-PAW against _E. coli, F. necrophorum_ and _P. levii_ was tested evaluating if proteins, which are present for example, on the skin of the cattle with DD might influence the overall Tb-PAW efficacy. The reduction rates of Tb-PAW applications containing 5% BSA and without BSA are shown in Figure 4. As described above, the Tb-PAW could significantly (\(p\leq 0.05\)) reduce all bacterial species below the detection limit. Under the influence of 5% BSA _E. coli_ was significantly reduced by 4.48 \(\pm\) 0.42 log values. The reductions for _F. necrophorum_ and _P. levii_ using 5% BSA were 4.39 \(\pm\) 0.28 and 4.55 \(\pm\) 0.37 log values, respectively. The addition of 5% BSA to the Tb-PAWs revealed no significant impact on occurring reduction rates. The 30% BSA solution contained NaN3 as an antimicrobial agent, thus control samples with the existing concentrations of NaN3 (0.1 mg/L) were additionally analyzed during the BSA-impact study. No significant differences between all groups could be obtained. The results are reported in the Supplementary Material (see Table S1). The presented results disagree with other studies revealing a buffer effect of organic materials, which can considerably reduce antimicrobial activities of PALs [39; 40]. BSA is described as a protein that can not only form a physical barrier between microorganisms and reactive species, but also actively interacts with free radicals leading to a decrease in the antimicrobial properties of PALs [39; 41]. For example, [PERSON] et al. [39] demonstrated that BSA reduced the antimicrobial efficacy of PAW against _S. aureus_ after a treatment time of 10 min. In the study by [PERSON] et al. [40], bacterial suspensions were added after combining beef extract or peptone with PAW (different protein concentrations) and after a waiting time of 15 min resulting in decreasing bacterial reduction properties with increasing protein concentrations.