## 4 Discussion
The obtained data showed that the content of secondary metabolites depended more on the type of cultivar than different water source regimes [26]. A comparison of the chemical composition and antioxidant activity between leaves and infloresances of hops was previously carried out. For example, [PERSON] et al. [27] reported the data on the aqueous extracts of Obyknovenny hops produced in Russia. In the two samples, the content of \(\alpha\)-acids and total phenols was similar in terms of quality but different from a quantitative point of view with poorer leaf extract and less antioxidant power. [PERSON] and co-authors [28] investigated cv. Aurora and cv. Hallertauer Magnum from four different European hop-growing regions in Slovenia, Austria, Germany and the Czech Republic, respectively. The infloresances had both higher levels of phenols and greater radical scavenging ability in the DPPH assay. Despite this, the leaf extract from one of the two cultivars was found to be the best iron reducer. More recently, [PERSON] et al. [29] found that 99% methanol extract from hops infloresances and leaves (unspecified cultivar) had similar total polyphenic content and a good activity against DPPH. [PERSON] and collaborators [30] explored the feasibility of using Magnum hops leaves and infloresances in varying percentages as functional components of teas. After preparation, the estimation of the total polyphenol content and free radical scavenging power demonstrated their richness in phenolic compounds and, in general, a greater capacity of tea containing hops leaves than those prepared with hops infloresances in reducing the DPPH radical. The analysis of Lithuanian hops showed similar results in terms of total polyphenols and flavonoids and anti-radical activity between the four studied cultivars and some differences between their leaves and cones [31]. [PERSON] et al. [32] confirmed the antioxidant activity of Chinock hops by testing the hot water, ethanol and CO\({}_{2}\) extracts obtained from the dried infloresances by two complementary in vitro assays, such as inhibition of hydroxyl radicals and protection of a \(\beta\)-carotene-linoleic acid model system. Any differences between the data on chemical profiles and related biological activity of these works and our obtained results on Chinock hops extracts can be reasonably attributed to the fresh and not dried or lyophilized starting plant material compared to the used solvent and/or to the extraction method, and the probable effects from both biotic (e.g., competitors, predators, parasites) and abiotic factors (physical or chemical such as soil, sunlight, temperature, water, salinity, oxygen, heavy metals) [33]. For example, in our previous work [11], the dried infloresances of the same hops cultivar, also grown in Italy but in a different area, were analyzed, highlighting a composition rich in \(\beta\)-myrcene, \(\beta\)-caryophyllene and humulene. While for these last two compounds the percentage values were almost overlapping, the content of \(\beta\)-myrcene was significantly lower than that found in fresh infloresances investigated in this study. A careful statistical investigation highlighted that for fresh leaves (Figure 3A), the most important compounds were \(\beta\)-caryophyllene (higher in powder than in unpowdered) and humulene (higher in unpowdered). On the other hand, for fresh leaves (Figure 3B), the most important compounds were \(\beta\)-myrcene (higher in unpowdered than in powdered) and humulene (higher in powdered than in unpowdered). In general, plant polyphenols, divided into two major groups, flavonoids and non-flavonoids, have antioxidant activity among their most important biological properties [34]. Likewise, terpen, a large and varied class of molecules produced by numerous plants, can function as antioxidant compounds. This prerogative is exploited in the pharmaceutical and cosmetic fields [35], and the search for antioxidant compounds among natural terpene compounds has significantly increased in recent years [36].