Study of Grape Polyphenols by Liquid Chromatography-High-Resolution Mass Spectrometry (UHPLC/QTOF) and Suspect Screening Analysis

Table 3

Stilbene [M-H]⁻ ions identified in Primitivo grape extract. Identification scores calculated with respect to the theoretical mass are reported. Numbers correspond to the peaks of chromatogram in Figure 6.

Peak	Stilbene compounds	Formula	Rt (min)	M-H^−		Error (ppm)
				Experimental	Theoretical
				/	/
1	E-Astringin (piceatannol glucoside)	C20H21O9	13.94	405.1198	405.1191	1.7
2	E-Piceid	C20H21O8	14.94	389.1249	389.1242	1.8
3	Z-Astringin	C20H21O9	15.12	405.1190	405.1191	−0.2
4	Piceatannol	C14H11O4	15.92	243.0666	243.0663	1.2
5	Z-Piceid	C20H21O8	15.97	389.1244	389.1242	0.5
6	Dimer 1 (pallidol)	C28H21O6	16.50	453.1347	453.1344	0.7
7	Pallidol-3-O-glucoside	C34H31O11	17.01	615.1869	615.1872	−0.5
8	Dimer 2	C28H21O6	17.16	453.1345	453.1344	0.2
9	trans-Resveratrol	C14H11O3	17.29	227.0716	227.0714	0.9
10	Caraphenol B	C28H21O7	17.91	469.1292	469.1293	−0.2
11	Tetramer 1	C56H41O12	18.10	905.2602	905.2604	−0.2
12	Tetramer 2	C56H41O12	18.49	905.2607	905.2604	0.3
13	Dimer 3 (Z--viniferin)	C28H21O6	18.61	453.1346	453.1344	0.4
14	Dimer 4 (E--viniferin)	C28H21O6	18.81	453.1346	453.1344	0.4
15	Trimer 1 (Z-miyabenol C)	C42H31O9	18.84	679.1976	679.1974	0.3
16	Trimer 2 (E-miyabenol C)	C42H31O9	18.93	679.1977	679.1974	0.4
17	Dimer 5 (-viniferin)	C28H21O6	19.56	453.1342	453.1344	−0.4