## 2 Materials and Methods
### EPR Spectroscopic Assessment of Antioxidant Capacities of Hop Oils  
The antioxidant capacity of the commercial hop oils was determined using the method previously described in reference [44]. A Bruker EMX EPR spectrometer (Bruker-Biospin, Germany), operating at room temperature (21 \(\pm\) 0.5 \({}^{\circ}\)C) at the X-band frequency, provided the electron paramagnetic resonance (EPR) spectra. The typical working parameters of the instrument were: microwave power, 20.12 mW; time constant, 40.96; gain, 1 \(\times\) 10\({}^{4}\) G; central field, 3480 G; and modulation amplitude, 2.0 G. The regression equations for the linear relationship between percent inhibition of the EPR signal intensity and the mole number of a given standard were assessed as y = 1547.8x + 4.7 for TR, y = 3767.6x + 2 for GA, and y = 1627.8x + 0.8 for AA, where y is inhibition [%] and x is sample volume [mL]. Based on these equations, we calculated the antioxidant capacity per 100 mL of the studied samples in umol TR, umol GA, and umol AA, respectively. A typical reaction mixture contained 1 mL of 200 umol L\({}^{-1}\) DPPH\(\bullet\) solution in ethanol and 0.025 to 0.100 mL of sample. For each sample, the regression equation of the linear relationship was determined between the percent inhibition (% I) of the EPR signal intensity and the volume of sample (\(V\)). This equation was used to calculate the % I value corresponding to 100 mL of the studied sample. Then, from the standard curves obtained for TR, GA, and AA, we calculated the antioxidant activity per 100 mL sample expressed in umol TR, umol GA, and umol AA, respectively. All measurements were performed in triplicate (n = 3). High-Performance Thin-Layer Chromatography--Effect-Directed Analysis (HPTLC-EDA) of Hop Oils and Selected Essential Oil Standards  
Hop oils (50 \(\mu\)L mL\({}^{-1}\) in cyclohexane--acetone, 1:1) and standards (5 \(\mu\)L mL\({}^{-1}\) in ethanol) were manually applied using a 10 microliter syringe (Hamilton, Bonaduz, Switzerland) in 0.5-5.0 \(\mu\)L band\({}^{-1}\) aliquots as 5 mm bands with a 9 mm track distance onto the HPTLC layers, at8 mm from the bottom. HPTLC separations were carried out with \(n\)-hexane or chloroform in an unsaturated 20 cm \(\times\) 10 cm Twin Trough Chamber (CAMAG, Muttenz, Switzerland) up to the migration distance of 65 or 75 mm, respectively. After development, the plates were dried in a cold stream of air and cut into segments using a smartCUT Plate Cutter (CAMAG) or a blade. Plate segments were derivatised by dipping them into anisaldehyde reagent (50 \(\mu\)L \(p\)-anisaldehyde, 10 mL methanol, 1 mL acetic acid, and 500 \(\mu\)L concentrated sulfuric acid (96%)), heated at 110 \({}^{\circ}\)C for 5 min, and then documented (digital camera, Cybershot DSC-HK60, Sony, Neu-Isenburg, Germany) under white light illumination in transmittance mode (Vis; 96891 Salobrena 2 LED lamp, Eglo Lux, Dunakeszi, Hungary). For SPME-GC-MS analysis, 70 \(\mu\)L aliquots of Azacca and Cascade oils and 30 \(\mu\)L of Azacca oil were applied as 7 cm bands and developed with chloroform or n-hexane, respectively. Zones of interest were eluted with ethanol using the TLC-MS Interface (CAMAG). Free radical scavenging activity was detected by dipping the chromatogram into a DPPH\(\bullet\) solution (0.02% in methanol). Antioxidants were indicated by bright zones against a purple background [45]. The HPTLC-\(\alpha\)-glucosidase assays were performed based on the previously described methods [37; 38], but with modifications. Substrates (2-naphthyl-\(\alpha\)-D-glucopyranoside or 4-methylumbelliferyl-\(\alpha\)-D-glucopyranoside) were dissolved in DMSO (10 mg in 0.4 mL) and diluted with 9.6 mL phosphate buffer (0.1 M, pH 7.5). The developed and dried chromatograms were first sprayed (airbrush, Revell, Bunde, Germany) with one of the substrate solutions and then with \(\alpha\)-glucosidase solution (5 units mL\({}^{-1}\) in 0.1 M phosphate buffer, pH 7.5). After spraying with each solution, the layers were allowed to become unglazed.