## 3 Results and Discussion
### Antimicrobial Activity  
Aqueous and ethanolic extracts of _C. sativa_ leaves at concentrations of 100 mg/mL and 10 mg/mL showed bactericidal activity against the Gram-positive bacterium _Staphylococcus aureus_. However, no antimicrobial effect was observed against other tested bacteria, including both Gram-negative (_Escherichia coli_, _Klebsiella pneumoniae_, _Pseudomonas aeruginosa_, _Serratia marcescens_) and Gram-positive (_Enterococcus faecalis_ and _Listeria monocytogenes_) strains. Additionally, the tested extracts did not exhibit antifungal activity against the _Candida albicans_ yeast. For both aqueous and ethanolic extracts, the use of a concentration of 1 mg/mL did not show antimicrobial effects (Figure 2A,B). Our findings corroborate previous studies indicating that _C. sativa_ leaves possess antimicrobial activity against _Staphylococcus aureus_[14, 47]. The results of microbiological analyses conducted by [PERSON] et al. (2020) demonstrate a comparable inhibitory effect on _Staphylococcus_ growth. Tenfold dilutions of a 45% aqueous extract of _C. sativa_ produced diameter zones of inhibition of _Staphylococcus aureus_ cultures in the range of 6 mm (20\(\times\)-320\(\times\) dilutions) to 13 mm (10-fold dilutions) [48]. Similarly, our analysis showed that aqueous extracts at concentrations of 10 and 100 mg/mL produced inhibition zones of 5.5-6 mm and 11-12 mm, respectively. For alcoholic extracts, the inhibition zones ranged from 7 to 10 mm and from 6 to 7 mm at concentrations of 10 and 100 mg/mL, respectively. In particular, other studies have shown a wider spectrum of susceptible microbial species compared to our work on the efficacy of the extract. In addition to inhibition of growth in _S. aureus_, a previous study demonstrated inhibitory effects against _Enterococcus faecalis_ and Gram-negative bacteria, namely _Escherichia coli_ and _Klebsiella pneumoniae_[48]. Similarly, another study reported that the soluble fraction of ethyl acetate from an aqueous leaf extract (pH 3.0) of _C. sativa_ exhibited inhibitory activity against six bacterial strains in addition to _Staphylococcus_, with MICs ranging between 64 and 256 ug/mL. _E. aerogenes_ and _S. aureus_ were the most sensitive bacteria (MIC = 62.5 ug/mL), while _Proteus vulgaris_, _Pseudomonas aeruginosa_ and _Enterococcus cloacae_ showed MIC values of 125 ug/mL. The least sensitive bacteria were _E. coli_ and _K. pneumoniae_ (MIC = 250 ug/mL) [14], confirming our analysis. The differences in the growth inhibition (halos) of the analyzed bacterial species in different  
Figure 2: Test results for antimicrobial analysis. (**A**) Water and ethanolic extracts of _C. sativa_ leaf-mediated changes in microbial growth. The tested microorganisms were treated with surface spots of _C. sativa_ leaf extracts at 100 mg/mL, 10 mg/mL and 1 mg/mL on indicator lawn media of NA agar (bacteria) and YPD agar (_Candida_). Representative micrographs of bacterial and yeast culture plates. (**B**) Table with diameters of bacterial growth inhibition (halos) induced by aqueous and ethanolic extracts of _C. sativa_ leaves at concentrations of 10 and 100 mg/mL. The values are expressed as means \(\pm\) SD of three biological replicates. Letters indicate statistically significant differences (capital letter < 0.001) among samples according to ANOVA and [PERSON]’s test. research papers are likely due to the different methods of extract application to the culture medium. In this study, extracts were applied using the spot method, unlike the agar well diffusion method, where 0.05 mL of the extract was introduced into a well in agar [47]. The variability in antimicrobial activity of different _C. sativa_ extracts is probably due to both the extraction solvent and the plant part used to produce them. This suggests that some active antimicrobial substances contained in the biomass dissolve to varying degrees in the applied solvents. The choice of solvent may depend on the desired metabolites to be extracted from the biomass of _C.