## 4 Discussion
excelsa_ contained only trace amount of these compounds. [PERSON] et al. [15] have also observed that hydroxybenzoic derivatives constitute the biggest part of _Juniperus axycedrus_ leaf phenolic acids. However, they found that salicylic and 4-OH benzoic acid were the most abundant ones. The highest concentration of phenolic glycosides was determined in the leaves of _J. communis_, _J. [PERSON]_, _[PERSON]. [PERSON]_, and _[PERSON]. [PERSON]_, whereas in the case of _J. [PERSON]_ and _[PERSON]. [PERSON]_, glycosides represented a relatively small portion of all polyphenols. Quercetin derivatives (e.g., rutin, isoquercetin, quercetin) were found to be predominant, reaching concentrations \(\geq\)2375.00 ng/mg. Quercetin, apigenin, luteolin and their glucosides, isorhamnetin glucosides, and catechin were previously reported in juniper samples [6; 15; 17; 30; 31]. In the study of [PERSON] and [PERSON] [32], catechin was found (206.654 ug/g extract), while rutin was found (110.203 ug/g extract) for _Juniperus axycedrus_ L. subsp. oxycedrus needles. We did not find free kaempfer, naringenin, or myricetin glucosides previously identified in some species [11; 13; 31]. However, we have detected free myricetin. Moreover, kaempfer 3-O-rutinoside was found in _J. communis_ 'Laxa', _J. formozana_, _J. sibrica_, _J. excelsa_, and _J. sabina_ var. _balkanensis_, and kaempfer 3-glucose (astragalin) with naringenin glucoside was found in all the studied species. All the studied juniperus species are very diverse in terms of polyphenolic profile. Moreover, the polyphenolic profile established for _J. communis_ 'Laxa' differed greatly from the one recently reported by [PERSON] et al. [31] for _J. communis_ shoot collected in Poland. Similarly, polyphenolic profiles of other studied juniper extracts are very diverse in terms of composition [6; 11; 17]. Therefore, it can be assumed that the species, variety, and origin strongly influence the phytochemical composition of juniper plant material. The major chemical components in the _J. excels_ leaves were monoterpene hydrocarbons, sesquiterpene hydrocarbons, and oxygen-containing sesquiterpenes [32]. Other major phenolic constituents found in extracts of _J. excels_ species are coumarins, lignans, sesquiterpenes, abietane, labdane and pimarane diterpenes, flavonoids, flavone glycosides, and tannins [33]. In leaves and seed cones extracts of _J. excels_, catechin, quercitrin, epicatechin, rutin, apigenin, and amentoflavone were present in substantial amounts. Phenolic acids were found in small amounts (0.26% and 0.48% of dry weight (DW) of leaves and seed cones, respectively); the dominant compounds were 2,5-dihydroxybenzoic and _p_-hydroxybenzoic acid. Furthermore, lignans, mainly matairesinol, were present in moderate amounts, primarily in seedcones, while coumarins were found in small amounts in both _J. excelsa_ extracts [34]. The antioxidant activity of a given plant extract depends on the plant's pchytochemical profile. Some of the phenolics (anthocyanidin, catechins, flavonoids), tannins (ellagic and gallic acids), phenyl isopropanoids (caffeic, coumaric, ferulic acids), lignans, catechol, and many others act as antioxidants [35]. There are many reports in the available literature on the antioxidant activity of juniper fruit [5]. The aqueous and ethanolic extracts from _J. communis_ L. fruits demonstrated a strong total antioxidant capacity at the concentrations of 20, 40, and 60 ug/mL. At these concentrations, both extracts of juniper fruit demonstrated effective reducing power, metal-chelating activity, as well as antiradical potential in various scavenging assays. These fruit extracts effectively inhibited the peroxidation of the linoleic acid [36]. However, most studies on the antioxidant potential of juniper concern essential oils [37; 38]. The in vitro antioxidant capacity of juniper oil has been observed using various free radical scavenging tests. It is mainly attributed to electron transport, which makes juniper essential oil a powerful antioxidant.