## 4 Discussion
In accordance with our study, the authors noted a dose-dependent effectiveness of the oil, whose highest concentration (100 \(\upmu\)g/mL) induced up to 100% growth inhibition of all evaluated strains. Low values for minimum inhibitory concentration (MIC) of _C. verum_ bark EO (0.1563 \(\upmu\)L/mL) against _P. corylophilum_ (declaring its antifungal efficacy) have been observed in the study performed by [PERSON] et al. [73]. The antifungal potential of cinnamon leaf EO against _Eurotium_, _Aspergillus_, and _Penicillium_ spp. has also been shown by the results of [PERSON] et al. [74]. Many scientific reports have documented that the antifungal properties of EOs can be connected to theattendance of individual bioactive substances present in their composition [7, 15]. Therefore, we assume that (_E_)-cinnamaldehyde may be responsible for the antifungal activities of our EOs (mainly CCEO, and CVBEO) which was also proven by [PERSON] et al. [75] whose findings revealed the substance to be effective against the growth of yeasts, bacteria, and microscopic filamentous fungi. Moreover, the inhibitory effects and mechanism of the substance's action on fungi growth and mycotoxin production have been demonstrated by [PERSON] et al. [76]. In this study, the growth of _A. flavus_ and aflatoxin B1 (AFB1) generation were completely inhibited by 0.80 mmol/L of cinnamaldehyde. Its lower concentration (0.40 mmol/L) markedly decreased AFB1 production with an inhibition scale of 68.9%, but it had no effect on fungal growth showing a dose-dependent effect. The inhibitory action of (_E_)-cinnamaldehyde against microorganism growth is based on the inhibition of ATPases [77] biosynthesis of their cell walls [78], and changes in their membrane structure and integrity [79]. In addition, the antifungal effects observed in our study may also be attributed to the high content of eugenol (the main compound in our CCVEO) which was evaluated in some previous reports dealing with the prevention of fungal spore germination and mycelial growth [80, 81, 82]. Mechanisms of eugenol action are associated with its destructive effects on the envelope of fungal cells [83], and with disruption of the cytoplasmic membrane due to the ability of its phenolic hydroxyl group to increase eugenol solubility in aqueous suspensions that improve its transition through the hydrophilic section of the cell envelope [84]. Since wheat bread is a staple food [85], we used it as a model food for _in situ_ evaluation of the antifungal efficacy of the EOs in the next part of our study. [PERSON] et al. [2] stated that this bakery product belongs to an intermediate-moisture food with MC ranging from 35 to 42% and value for a\({}_{w}\) above 0.95, which is in agreement with our results (40.89 \(\pm\) 0.88% and 0.946 \(\pm\) 0.002, respectively). Moreover, it is known that bread loaves are prone to mold spoilage after a few days of storage [3] which corresponds with our results demonstrating the growth of total microorganisms and fungi on our bread samples after two weeks of their storage period. Most importantly, the presence of coliform bacteria was not detected in our bread samples during the entire period of storage reflecting the safety of the bread and its correct production technology [86]. Among microorganisms detected in our study, the most isolated species was _Penicillium_ spp. which is in line with the results of [PERSON] and [PERSON] [4] recognizing _Penicillium_ as the most common kind of bread mold. Summarily, wheat bread is susceptible to microbial spoilage, suggesting its application as a suitable model substrate for similar kinds of experiments. The antimicrobial properties of diverse EOs have been intensively studied against several organisms _in situ_, commonly by direct contact methods [87, 88]. However, these methods may be less successful due to the high hydrophobicity or volatility of EOs, altering their antimicrobial effectiveness [89].