## 2 Results and Discussion
### Phenolic Acids and Polypphenols
The loading plot shows two groups of strong positive correlations: the 1 st group consists of ferulic acid, 3,5-di-O-caffeoylquinic acid, 4,5-di-O-caffeoylquinic acid, and citric acid, which are correlated with the reference Mate leaf, and the 2 nd group contains malic acid, neochlorogenic acid, chlorogenic acid, and rutin, which are positively correlated with all _I. aquifolium_. In addition, cryptochlorogenic acid seems to be able to distinguish _I. meserveae_. Many studies have been conducted on phenolic acid and polyphenol fractions from both _I. paraguariensis_ and other _llex_ taxa. A Polish team also conducted research on bioactive compounds in Yerba Mate, which is available on the local market. Quantitative analysis showed the presence of chlorogenic acids, with neochlorogenic acid as the dominant (5.4-39.0 mg g\({}^{-1}\)), followed by chlorogenic acid (1.8-19.0 mg g\({}^{-1}\)) and cryptochlorogenic acid (3.5-17.8 mg g\({}^{-1}\)). This shows a different trend from that observed in our study. In contrast, the caffe acid content was similar (0.4-0.6 mg g\({}^{-1}\)) [25]. In their study on the contents of flavonoids, phenolic acids, and xanthines in Yerba Mate, [PERSON] et al. found that the contents of chlorogenic acid and rutin in the phenolic acid fraction were 21.6 mg g\({}^{-1}\) and 6.8 mg g\({}^{-1}\), respectively [26]. Simultaneously, [PERSON] et al. conducted a study of the contents of bioactive compounds in spray-dried extracts and dehydrated leaves of _I. paraguariensis_. The contents of rutin (5.4 mg g\({}^{-1}\)), caffe acid (1.5 mg g\({}^{-1}\)), and neochlorogenic acid (91.4 mg g\({}^{-1}\)) were significantly higher than in dehydrated leaves, which contained 3.1 mg g\({}^{-1}\), 0.7 mg g\({}^{-1}\), and 24.8 mg g\({}^{-1}\)[27]. A study by [PERSON] et al. determined the contents of chlorogenic acids in European varieties of _I. aquifolium_ Argenteta Marginata and _I. meserveae_ Blue Angel, and identified chlorogenic acid as the predominant compound (11.6-23.3 mg g\({}^{-1}\)), with neochlorogenic (1.7-5.1 mg g\({}^{-1}\)) and cryptochlorogenic (2.2-5.3 mg g\({}^{-1}\)) being present as minor isomers. Figure 6: Principal component analysis of _llex_ taxons based on the contents of its polyphenol and phenolic acid constituents; PA—_I. paraguariensis_, AM—_I. aquifolium_ Aurea Marginata, SQ—_I. aquifolium_ Silver Queen, HNS—_I. aquifolium_ Handsworth New Silver, BP—_I. meserveae_ Blue Prince, BG—_I. meserveae_ Blue Girl, BPR—_I. meserveae_ Blue Princess; RT—rutin, QA—quinic acid, FA—fermic acid, CA—citric acid, MA—malic acid, QR—quercetin, CCHL—cryptochlorogenic acid, NCHL—neochlorogenic acid, CHL—chlorogenic acid, 3,5 DQA—3,5-di-O-caffeoylquinic acid, 4,5 DQA—4,5-di-O-caffeoylquinic acid. However, in _I. paraquiensis_, neochlorogenic acid (19.7 mg g\({}^{-1}\)) was present at the highest concentration. Quantitatively, 3,5- and 4,5-di-O-caffeoylquinic acids in both European and Argentinian varieties were present at levels comparable to our results. The rutin content in the samples from the Argentinian species was about half of that in European _Ilex_, which is also confirmed in Table 3 above [28]. [PERSON] et al. obtained a lower rutin content of about 0.8 mg g\({}^{-1}\) and a chlorogenic acid content of 0.3-28.0 mg g\({}^{-1}\) from the Chinese _Ilex kudingcha_ and _Ilex cornuta_ species [29]. [PERSON] et al. observed a relationship analogous to that observed by our team when they analysed chlorogenic acids (chlorogenic acid > neochlorogenic acid > cryptochlorogenic acid) in water extracts of _Ilex guayusa_. However, the quantitative relationship between 3,5 and 4,5-di-O-caffeoylquinic acids was the opposite; that is, 2.3 g L\({}^{-1}\) and 3.4 g L\({}^{-1}\)[30]. Using LC-MS/MS, a team of researchers qualitatively identified the chlorogenic acids, 3,5 and 4,5-di-O-caffeoylquinic acid, caffe acid and vanillic acid, and the glucosides of the aforementioned phenols in _I. glabra_[31]. [PERSON]'s team from the USA tested more than a dozen _Ilex_ samples for metabolomic and chemotaxonomic purposes.