## 4 Discussion  
For a very long time, wild fruits found in forests and orchards have been used in Polish folk medicine. Now, their popularity has been growing, and they have become increasingly available in shops and herbalists. Due to media coverage, an increase in the culinary use of some wild plants for food, drinks, and medicine can be observed. Studies on polyphenols in the herein-selected fruits are often carried out using chromatographic or spectrophotometric methods. However, most of these studies focus on pooled and general characteristics, such as total phenolic content [14; 27], total phenolic acids [27; 28], total flavonoid content [7; 29], total monomeric anthocyanin content [27], total antioxidant activity [14], or single polyphenic compounds. Although EA and Q are very common among over 8000 of \"phenolics\", there are surprisingly few papers specifically measuring the contents of these two compounds in Polish medicinal fruits. Discussing EA and Q together is valuable because, despite their structural differences, both have anticancer properties, and their activity is synergistic. It has been confirmed that EA and Q together have a greater effect on human leukemia cells than can be explained by a simple additive effect. Fruits like blueberries, raspberries, and strawberries, which contain both EA and Q, are used in studies examining biochemical interactions [30]. Their synergistic action has been demonstrated in studies of cytotoxicity in models using different human cancer cells (lung-line A549, colorectal-line HCT-116, and breast-line MDA-MB-231) [31]. Figure 3: Comparison of TPC (**A**) and TFC (**B**) values in studied the fruit samples. Moreover, EA and Q have been identified together as distinctive tyrosinase (TYR) inhibitors in the study of _Geranium_ sp. activity, used in folk medicine. TYR is a multifunctional enzyme associated with the pathogenesis of melanoma and other pigmentation disorders [32]. Furthermore, studies about EA and ellagitannins mainly focus on pomegranate extract and its vasculoprotective effects [33] and anticancer activity [34]. Our findings show that wild fruits of barberry, blackthorn, elderberry, lingonberry, rownberry, and sea-buckthorn contain both EA and Q. In contrast, EA was not detected in some chokeberry and hawthorn samples. Thus, these wild plants can serve as promising materials for biochemical research. We decided to determine the content of EA and Q in the unconjugated forms, as the final effects of dietary polyphenols--particularly those that are glycolysated or oligomeric/polymeric--depend on the composition and function of the gut microbiota [35]. Unbound forms are more readily bioavailable because they do not require multi-step catabolism, primarily hydrolysis mediated by the gut microbiota, which is highly variable and influenced by various factors [36]. Selected medicinal fruits, predominantly red or orange-red in color, represent complex matrices due to high anthocyanin content. Consequently, chromatographic analysis of such material employing an ultraviolet detector, such as HPLC-UV-Vis or HPLC-PDA, can be challenging. The usage of mass spectrometric detection allows for more accurate identification of compounds and shorter analysis time. Considering the above advantages, LC-MS or LC-MS/MS systems have increasingly been used for simultaneous or individual quantitative analysis of EA and Q in a variety of plant materials and food products [25; 37; 38]. Among the studied wild fruits, the highest contents of free EA were noted for sea-buckthorn. Interestingly, some other researchers did not find EA in this fruit [39]. In the available literature, these compounds are not extensively studied and described, but data on the free EA content in blackthorn, barberry, and elderberry fruits are very limited or researchers did not confirm the presence of this phenolic acid in medicinal fruit such as rowanberry (Table 4).