## 3 Results
### Antibacterial Effects of T. vulgare Extracts
#### 3.3.1 Antibacterial Susceptibility--Agar Disc Diffusion Test  
The results of the agar disc diffusion test for antibacterial effects of the extract are shown in the Table 1. Analysis of the inhibition zone results of _T. vulgare_ flower extract showed that extracts made with a low-concentration solvent such as 30% ethanol and 30% acetone had no antibacterial effects. The 50% ethanol extracts of flowers were effective against the _S. aureus_ bovine isolate and _E. coli (V252)_. The 50% acetone extracts of flowers were effective against both _S. aureus_ strains, _E. coli (V252)_, and _S. agalactiae_. The 70% ethanol and 70% acetone extracts of flowers were both effective against _S. aureus_, _E. coli_, and _S. agalactiae_, but had no effect against _S. uberis_ or _Serratia liquefaciens_. There was no  
Figure 4: FTIR DRIFT spectra. (**A**) _T. vulgare_ parts: flowers and leaves; (**B**) Extract in 70% acetone of _T. vulgare_ parts: flowers and leaves; (**C**) Extract in 70%, 50%, and 30% ethanol of _T. vulgare_ flowers. significant difference between the results of 70% ethanol extracts and 70% acetone extracts of flowers (Table 2). Because ethanol is considered safer than acetone, it was used for further extract preparation and antibacterial analysis. All leaf extracts of _T. vulgare_ had an effect against the isolate of _S. aureus_ bovine mastitistits, _S. uberis_, and _Serratia liquefaciens_. The 70% ethanol extracts of leaves of _T. vulgare_ and all types of acetone extracts showed effectiveness against _S. aureus ATCC_ 25923 and _S. agalacliae_, but only the 70% acetone extract had a minimal effect against the reference culture of _E. coli_ \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Extract Sample** & **Extraction Solvent** & **TPC GAE mg/g DW \(\pm\) SD** \\ \hline \multirow{6}{*}{_T. vulgare_ flower} & Ethanol 30\% & 62.5 \(\pm\)10.9  \\  & Ethanol 70\% & 62.3 \(\pm\)9.2  \\  & Acetone 50\% & 77.4 \(\pm\)3.4  \\ \hline \multirow{6}{*}{_T. vulgare_ leaf extract} & Ethanol 30\% & 28.7 \(\pm\)9.6  \\ \cline{2-3}  & Ethanol 70\% & 24.5 \(\pm\)4.5  \\ \cline{2-3}  & Acetone 50\% & 28.1 \(\pm\)3.6  \\ \hline \hline \end{tabular}  
* TPC—Total Phenolic Content, GAE—Gallic Acid Equivalent, DW—Dry Plant weight, SD—standard deviation. Within columns, values with the same superscript letter are not significantly different at the \(p\leq 0.05\) level according to ANOVA and post hoc Tukey test.  
\end{table} 
Table 1: Total Phenolic Content of the ethanol and acetone extracts of flowers and leaves of _T. vulgare_. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline  & & & & & & & & & & \\ \cline{3-10}  & & E30\% & n & n & n & n & n & n & n \\  & E50\% & n & 17.0 \(\pm\) 2.5  & n \\  & E70\% & 14.8 \(\pm\) 1.3  & n & 9.3 \(\pm\) 1.2  & 7.8 \(\pm\) 0.5  & n \\ \cline{2-3}  & & A30\% & n & n & n & n & n & n & n \\  & A50\% & 19.0 \(\pm\) 2.5  & n & 8.3 \(\pm\) 0.5  & n \\  & A70\% & 15.3 \(\pm\) 2.1  & n & 8.3 \(\pm\) 0.5 [FOOTNOTE:]Footnote : footnotemark: [ENDFOOTNOTE] & n & 8.0 \(\pm\) 0 [FOOTNO_ATCC_ 25922. The best antibacterial effect was noted for 70% acetone and 70% ethanol extracts--with inhibition zone diameters ranging from 8.0 mm to 24.3 \(\pm\) 2.9 mm and from 9.3 \(\pm\) 1.3 mm to 24.3 \(\pm\) 2.9 mm, respectively. Antibacterial effectiveness increased against _S. aureus_ with an increase in concentration of the solvent, but no such relationship was observed for the rest of the bacterial samples. Since there were no significant differences (Table 2) between measurements amongst effective extracts, for further analysis, we chose the 70% ethanol extract of _T. vulgare_ leaves as it is considered a safer solvent. 3.2 Broth Microdilution Method for Determination of Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC)  
To determine precise effective concentrations of most active extracts, we applied broth microdilution tests, and the results are shown in Table 3. _T. vulgare_ flowers were effective against _E. coli_ strains, _S. aureus_ strains, and _S.