## 4 Discussion
These authors reported that the ABTS value for lemon balm was 10.97 mmol Trolox/L, while it was 3.49 mmol Trolox/L for peppermint and 3.27 mmol Trolox/L for lavender. After three months of storage at various temperatures, about 50% of antioxidant activity was lost. [PERSON] et al. [31] confirmed the high oxidative capacity of lemon balm, which is in the range of 27.95-43.08 mg Trolox/g FM for the first harvest and 32.40-45.57 mg Trolox/g FM for the second. In these studies, extracts were prepared using 50% methanol. Different results were obtained by [PERSON] et al. [46] by comparing the antioxidant capacity of the same species with unknown growing conditions in methanol: water (80.20, \(v/v\)) extracts. The highest values were obtained for peppermint (2.59 mg Trolox/g FW), followed by lavender (2.54 mg Trolox/g FW) and lemon balm (1.39 mg Trolox/g FW). The high antioxidant capacity of lemon balm has also been confirmed in the FRAP method, especially in methanol solution. However, in this case, no statistical difference was found between lemon balm and mint. In the literature on the subject, it is difficult to find a simultaneous comparison of the antioxidant properties of the same species in different solvents. [PERSON] et al. [44], testing water infusions of these species, obtained the highest values for lemon balm (14.20 mmol Trolox/L) compared to peppermint (6.17 mmol Trolox/L) and lavender (3.72 mmol Trolox/L). The results obtained by [PERSON] et al. [47] using aqueous extracts clearly indicate lemon balm as the dominant species in terms of antioxidant properties. Similarly, [PERSON] et al. [31] confirmed the high antioxidant capacity of lemon balm, which varies depending on the production and harvesting method in the range of 83.82-150.70 mg Trolox/g FW for the first harvest and 55.96-105.08 mg Trolox/g FW for the second harvest. In these studies, extracts were prepared using 50% methanol. In turn, [PERSON] et al. [46] compared the antioxidant capacity of the same species using the FRAP test and obtained different results. Peppermint had the highest antioxidant potential (1.88 mg Trolox/g FW), followed by lavender (1.19 mg Trolox/g FW) and lemon balm (0.40 mg Fe/g FW). In this case, the tests used methanol:water solutions (80:20, \(v/v\)). In this study, we have found that the highest level of polyphenolic compounds was measured in the infusion of peppermint as compared to other extracts (Table 2). Similarly, the same order for these herb species was observed by [PERSON] et al. [45]. These authors have used 50% ethanol-water extracts for polyphenol determination. The total content of polyphenols in peppermint was also higher compared to lemon balm in the study by [PERSON] et al. [48] and was in the range of 91.80-101.43 for mint and 40.90-65.84 mg/g eq for lemon balm expressed as tannic acid. Moreover, they showed that the total content of polyphenols in both species increased after the application of mineral and biological fertilization. Similar results were found in the study of [PERSON] et al. [49], who extracted total polyphenols using 10 mL of 80% methanol and obtained 0.467, 0.340 and 0.560 mg GAE/kg FW. These authors also found that the total phenolic compound depended on the application of the protein solution in various concentrations (0.0%, 0.25% and 0.50%) during the growth in a hydroponic system. It should also be noted that regardless of the solvent used, lavender had a much lower polyphenol content compared to other species. However, as research by [PERSON] et al. [50] indicates, the content of polyphenolic compounds may be related to the genotype used in the research. However, from a general point of view, frozen samples of medicinal plants are characterized by a lower content of phenolic compounds [47]. [PERSON] et al. [33] assessed the total polyphenol content in a 50% ethanol solution for beer mint. They obtained the lowest value for fresh mint (12.43 mg) and the highest (27.12 mg) gallic acid equivalents (GAEs) (g D.M.)