“…In detail, numbered according to the elution order (t R , Table 3 ): 3,4,5-trihydroxybenzoic acid 1 (gallic acid, GA), 3,5-dihydroxybenzoic acid 2 (3,5-DHBA), 3,4-dihydroxybenzoic acid 3 (protocatecuic acid, PCA), 5-caffeoylquinic acid 4 (5CQA), 2,5-dihydroxybenzoic acid 5 (2,5-DHBA, gentisic acid), catechin 6 (Cat), 4-caffeoylquinic acid 7 (4CQA), p -hydroxybenzoic acid 8 (pHBA), vanillic acid 9 (VA), caffeic acid 10 (CA), syringic acid 11 (SyA), m -hydroxybenzoic acid 12 (mHBA), 2,6-dihydroxybenzoic acid 13 (2,6-DHBA), coumaric acid 14 (CuA), sinapic acid 15 (SA), ferulic acid 16 (FA), rutin 17 (Ru), myricitrin 18 (My), quercetin-3-O-glucoside 19 (Q3G), kampferol-3-O-rutinoside 20 (K3R), salicylic acid 21 (SaA), hesperidin 22 (He), quercetin 23 (Q), kampferol 24 (K), isoxanthohumol 25 (IsoX), xanthohumol 26 (X). The analysis was carried out by an HPLC-ESI-MS/MS in SIR mode method previously developed for 14 compounds ( 1 , 3 , 4 , 8 – 12 , 14 – 17 , 23 , 24 ) (Petrucci et al 2020b , 2021 ) and herein slightly modified to include 12 more compounds ( 2 , 5 – 7 , 13 , 18 – 22 , 25 , 26 ), whose quality-of-analysis parameters are resumed in Table 2 . Briefly, all calibration curves showed a good linearity in the investigated concentration range 10 ÷ 80 µg/L, as evidenced by the R 2 values ranging within 0.9715 ÷ 1 (the minimum value 0.9715 was found for X), reported in Table 2 ; LOD and LOQ values were in the concentration ranges 0.070 ÷ 10.23 µg/L and 0.22 ÷ 31.01 µg/L, respectively (the higher LOD and LOQ values were found for SaA).…”