Table 1.

Peak assignments of the aqueous methanol extract of Mexican oregano

Peak no.a	tR (min)	[M+H]+/[M−H]− (m/z)	[A+H]+/[A−H]− (m/z)	UV λmax (nm)	Identification
1	11.90	467/465	305/303	288,360	Pentahydroxyflavanone-A hexoside (II-6-A)
2	13.13	465/463	303/301	282,344	6-Hydroxyluteolin 7-O-hexoside (I-8-A)
3	15.00	467/465	305/303	288,364	Pentaflavanone-B hexoside-1 (II-7-A)
4	15.27	467/465	305/303	288,364	Pentaflavanone-B hexoside-2 (II-7-B)
5	18.83	449/447	287/285	284,334	Scutallarein 7-O-hexoside (I-3-A)
6b	19.46	449/447	287/285	256,266sh,346	Luteolin 7-O-glucoside (I-6-A)
7b	20.34	305/303	—	290,336sh	Taxifolin (II-5)
8c	24.42	449/447	303/301	282,346	6-Hydroxyluteolin 7-O-rhamnoside (I-8-B)
9	24.52	303/301	—	282,346	6-Hydroxyluteolin (I-8)
10	25.07	453/451	291/289	226,286	3-Hydroxyphloretin 6′-O-hexoside (III-2-A)
11b	26.46	433/431	271/269	268,338	Apigenin 7-O-glucoside (I-2-A)
12b	32.61	437/435	275/273	226,286	Phloridzin (III-1-A)
13b	33.80	287/285	—	284,338	Scutellarein (I-3)
14b	41.88	289/287	—	288,336sh	Eriodictyol (II-4)
15b	43.51	287/285	—	256,266sh,348	Luteolin (I-6)
16b	44.08	303/301	—	256,266sh,370	Quercetin (I-7)
17b	50.63	273/271	—	292,332sh	Naringenin (II-2)
18c	50.98	301/299	—	276,336	6-Methylscutellarein (I-4)
19	57.00	315/313	—	278,334	6,7-Dimethylscutellarein (I-5)
20b	61.23	287/285	—	290,336sh	Sakuranetin (II-3)
21b	61.83	257/255	—	290,334sh	Pinocembrin (II-1)
22b	62.12	271/269	—	266,314sh,360	Galangin (I-1)
23	63.63	285/283	—	266,340	Methylgalangin (I-9)

^aPeak numbers in Fig. 2.

^bThe identification was confirmed by direct comparison with standard compound, respectively.

^cDetermined from their peak in the LC chromatogram of TLC band-6 or other TLC band.