Table 1.

Main classes of compounds identified by LC-UV-ESI-MS² in crabapple leaves.

No.	MW	[M-H]^−a	MS²[M-H]-(m/z)^a	Putative identify	RL	GL	Classification
1	626	625	[625]:463,301	Quercetin-3-O-diglucoside (P1)^c(Sanchez-Rabaneda et al., 2004)	√	√	Flavonol
2	449	–	[449]:287	Cyanidin-3-O-galactoside (P2)^b	√	ND	Anthocyanin
3	354	353	[353]:191,173,179	4-O-caffeoylquinic acid (P3)^b	√	√	Phenolic acid
4	466	465	[465]:285,241	Taxifolin-3-O-glucoside (P4)^b	√	ND	Dihydroflavonol
5	578	577	[577]:451,425,407	Procyanidin B2 (P5)^b	√	√	Flavan-3-ols
6	518	517	[517]:385	Xyloside roseoside (P6)	ND	√	Terpenoids
7	450	449	[449]:269	Astilbin (P7)^b	√	ND	Dihydroflavonol
8	386	385	[385]:223	Roseoside (P8)^c(Winterhalter et al., 1994)	√	√	Terpenoids
9	290	289	[289]:245,205	(-)–Epicatechin (P9)^b	√	√	Flavan-3-ols
10	610	609	[609]:565,301	Rutin (P10)^b	√	√	Flavonol
11	464	463	[463]:301	Quercetin-3-O-glucoside (P11)^b	√	√	Flavonol
12	464	463	[463]:301	Quercetin-7-O-glucoside (P12)	√	√	Flavonol
13	434	433	[433]:301	Quercetin-3-O-arabinoside (P13)^b	√	√	Flavonol
14	506	505	[505]:463,301	Acetyl quercetin-3-O-glucoside(P14)	√	√	Flavonol
15	506	505	[505]:463,301	Acetyl quercetin-7-O-glucoside (P15)	√	√	Flavonol
16	434	433	[433]:301	Quercetin-7-O-arabinoside (P16)	√	√	Flavonol
17	448	447	[447]:301	Quercetin-3-O-rhamnoside (P17)^c(Lommen et al., 2000)	√	√	Flavonol
18	436	435	[436]:273	Phloridzin (P18)^b	√	√	Dihydrochalcone
19	594	593	[593]:447:285	Luteolin-5-O-rutinoside (P19)	ND	√	Flavone

MW, molecular weight.

Obtained by ion trap mass spectrometry.

Identification confirmed by direct comparison with standards.

Identification confirmed by reference compounds in the plant sample.

P1–P19, serial number of the identified compounds, used henceforth.

RL and GL, the ever-red and ever-green leaves, respectively from M.cv. “Royalty” and M.cv. “Flame” crabapple, used henceforth.

ND, none detected; √, detected.