## 3 Results and Discussion
### Assessment of Antioxidant Activity  
It is well-known that free radicals initiate the process of lipid peroxidation and the propagation of the chain of radical structures. Therefore, several methods have been developed to determine compounds' antioxidant properties [39; 40; 41]. For example, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazol-6-sulfonic acid) radical (ABTS) assays are two spectrophotometer techniques widely employed for assessing the antioxidant properties of natural extracts. Briefly, the DPPH method is based on reducing the purple DPPH radical to 1,1-diphenyl-2-picryl-hydrazine (DPPH-H). In contrast, the ABTS method implicates the reduction or radical scavenging of a blue/green ABTS radical to a colorless sulfonic acid [42]. Butylated hydroxyanisole (BHA) and ascorbic acid were used as the positive control. The IC\({}_{50}\) values were computed employing BioDataFit 1.02 program (Chang Broscience Inc, Castro Valley, CA, USA). In our study, OEO reduced the stable free radical DPPH with an IC\({}_{50}\) value of 93.12 \(\pm\) 0.03 \(\upmu\)g/mL (Table 3). [PERSON]'s test shows that the OEO's DPPH values are significantly lower than ascorbic acid (_p_ < 0.01). Previously, [PERSON] et al. documented low antioxidant capacity for Romanian _O. vulgare_ var. _aureum_ volatile oil, with a 58.18 \(\pm\) 0.07% inhibition [33]. Comparable effects were reported by [PERSON] et al. for oils isolated from _O. vulgare_ var. _aureum_ leaves and flowers with 63.1 \(\pm\) 0.7% and 66.4 \(\pm\) 2.23% inhibitions [34]. Better results were documented for oils extracted from _O. vulgare_ var. _aureum_ stems and whole plant, respectively, with inhibitions ranging between 80.3 \(\pm\) 0.01% to 88.6 \(\pm\) 0.1% [34]. However, because of the various modes of result expression used in different studies, directly comparing our findings with those reported in the literature is difficult. Nevertheless, the DPPH radical scavenging ability registered for the studied OEO is in accord with those previously described for _O. vulgare_ (46.66-97.61 \(\upmu\)g/mL), _Poliomithna longiflora_ (83.70 \(\pm\) 4.12 \(\upmu\)g/mL), _O. onites_ L. (116.74-132.93 \(\upmu\)g/mL) and _O. srivicum_ (91.45 \(\pm\) 2.30 \(\upmu\)g/mL) EOs [43; 44; 45; 46]. In the ABTS assay, OEO exhibited a good ability to scavenge the ABTS radical (IC\({}_{50}\) 27.63 \(\pm\) 0.01 \(\upmu\)g/mL) (Table 3), significantly more potent (_p_ < 0.01) than standard ascorbic acid (IC\({}_{50}\) 35.89 \(\pm\) 0.05 \(\upmu\)g/mL) according to the [PERSON]'s test. In contrast, BHA revealed significantly (_p_ < 0.001) higher antioxidant capability (IC\({}_{50}\) 8.71 \(\pm\) 0.01 \(\upmu\)g/mL) compared to OEO and ascorbic acid. Nevertheless, our results reveal that OEO was more effective in scavenging ABTS radicals than other oregano species: _O. tyttanthum_, _O. compactum_, _O. vulgare_, and _L. graveolens_[47; 48; 49; 50]. Previously published research investigating the DPPH and reactive oxygen species scavenging capability of different extracts discovered that these extracts have similar scavenging performance in both cases [51; 52]. This is to be expected, given that it is dependent on the extract components' capacity to reduce free radicals. Based on this, OEO could be a good source of antioxidants that can also quench endogenous reactive oxygen species. The beta-carotene/linoleic acid bleaching assay is based on the discoloration of beta-carotene determined by its reaction with the radicals resulting from the oxidation of linoleic acid in an emulsion. The presence of an antioxidant can delay the rate of beta-carotene discoloration. Table 3 displays the inhibition of beta-carotene bleaching by the OEO and the