## 3 Results and Discussion
### Hemolytic Activity of R. tylphina Fruit Extract  
Considering our encouraging results indicating antioxidant and antistreptomycinococcus properties of the _R. tylphina_ fruit extract to be potentially used as an herbal remedy, it was tested for hemolytic activity against sheep erythrocytes to assess an initial extract toxicity profile, as some natural extracts might exhibit cytotoxic effects against eukaryotic cells.  
The results of the hemolytic activity of the concentrated _R. tylphina_ fruit extract (BBE, 61.51% ethanol, 20/1 (\(v/w\)) solvent/solid ratio, 5 min, 2.8 mm ceramic beads) are shown in Figure 10. Four dilutions of the _R. tylphina_ fruit extract--125, 250, 500, and 1000 ug/mL--were tested on RBCs by the erythrocyte viability assay, as previously described [49]. As noticed, hemolysis increases with increased concentration of the fruit extract.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Category** & **Microbial Strain** & **Zone of Inhibition** \\ \hline \multirow{4}{*}{Gram-positive bacteria} & _Bacillus subtilis_ ATCC 6633 & 8 \\  & _Enterococcus faecalis_ ATCC 29212 & 8 \\  & _Enterococcus faecalis_ VRE ATCC 51299 & – \\  & _Staphylococcus aureus_ ATCC 25923 & – \\  & _Streptococcus pyogenes_ ATCC 19615 & 20 \\ \hline \multirow{4}{*}{Gram-negative bacteria} & _Acinetobacter baumannii_ ATCC 19606 & – \\  & _Citrobacter freundi_ ATCC 13316 & – \\  & _Escherichia coli_ ATCC 25922 & – \\  & _Klebsiella arcongues_ ATCC 13048 & – \\  & _Klebsiella pneumoniae_ ATCC 13883 & 8 \\  & _Pseudomonas aeruginosa_ ATCC 27853 & – \\  & _Salmonella enterica_ ATCC 13076 & 12 \\ \hline \multirow{2}{*}{Microscopic fungus} & _Candida albicans_ ATCC10231 & – \\  & _Saccharomyces cerevisiae_ ATCC59763 & – \\ \hline \multirow{4}{*}{Gram-positive bacteria} & Clinical/food bacterial isolates & \\ \hline \multirow{4}{*}{Gram-positive bacteria} & _Staphylococcus aureus_ (clinical isolate) & – \\  & _Staphylococcus aureus_ (food isolate) & – \\  & _Streptococcus angsinosus_ (clinical isolate) & – \\  & _Streptococcus angsinosus_ group F (clinical isolate) & – \\  & _Streptococcus mutans_ (clinical isolate) & – \\ \hline Gram-negative bacteria & _Salmonella_ group D (clinical isolate) & 8 \\ \hline \hline \end{tabular}
\end{table}
Table 12: Inhibition zones (mm) of tested pathogenic microorganisms in the presence of the ethanolic extract from _R. tylphina_ fruits.  
Figure 10: Hemolytic activity of _R. tylphina_ fruit extract at different concentrations.  
The hemolytic activity increased with the extract concentration. The highest value (19.85 \(\pm\) 1.30%) was found at 1000 \(\upmu\)g/mL of the fruit extract (Figure 10). Even at the highest concentration, the hemolytic activity indicates a reduced toxic effect on sheep RBC, according to the general consideration of low toxicity at hemolysis lower than 20% (98,99). However, the authors considered that such results cannot guarantee that an extract will not be toxic to other cells in the human body.  
The hemolytic activity at which 50% of RBCs were lysed, HC\({}_{50}\), was determined based on a regression calculation using the equation Y = 0.0214X \(-\) 1.2169, from the plot of hemolysis as a function of extract concentration. The found HC\({}_{50}\) value was 2393.3 \(\upmu\)g/mL.  
No studies have been reported on the hemolytic activity of fruits of staghorn sumac. However, [PERSON] et al. (2014) (2014) described antihemolytic effect of _R. typhina_ leaf extract at 10 \(\upmu\)g/mL on human red cells.  
As indicated in Figure 11, the Kruskal-Wallis test applied to our experimental data showed a significant difference between the mean values of hemolysis and the extract concentration (\(p\) = 0.016). [PERSON]'s test for multiple comparisons indicated that the mean hemolysis percentage at 125 \(\upmu\)g/mL is significantly lower than the one found at 1000 \(\upmu\)g/mL (\(p\) = 0.0067 *).