Table 1.

Discriminant polyphenol compounds identified by the VIP (variable importance in projection) with a score > 1.2. VIP makers were classified in classes and subclasses according to the Phenol Explorer database. Each compound as provided with a VIP score ± standard error and log fold-change values obtained by pairwise comparison among different Cydonia oblonga Mill. organs.

Class	Sub-Class	Discriminant Compound (OPLS-DA)	VIP Score ± SE	Log FC [Leaf] vs. [Stem]	Log FC [Leaf] vs. [Whole Fruit]	Log FC [Stem] vs. [Whole Fruit]
Flavonoids	Anthocyanins	Petunidin 3-O-glucoside	1.23 ± 0.31	−2.63	1.98	4.61
		Delphinidin 3-O-arabinoside/Delphinidin 3-O-xyloside	1.23 ± 0.30	−2.45	−0.08	2.37
		Cyanidin 3-O-xyloside/Cyanidin 3-O-arabinoside	1.22 ± 0.33	−2.55	−0.22	2.33
		Cyanidin 3-O-(6″-malonyl−3″-glucosyl-glucoside)	1.22 ± 0.32	0.68	−1.43	−2.11
		Cyanidin 3-O-sambubioside 5-O-glucoside	1.21 ± 0.35	−5.03	−2.14	2.89
		Pelargonidin 3-O-sambubioside	1.21 ± 0.33	−7.07	5.10	12.16
		Peonidin 3-O-(6″-acetyl-glucoside)	1.21 ± 0.33	−3.58	0.22	3.81
		Cyanidin 3-O-xylosyl-rutinoside	1.21 ± 0.27	−1.18	16.11	17.29
	Dihydrochalcones	3-Hydroxyphloretin 2′-O-xylosyl-glucoside	1.20 ± 0.32	−4.04	−2.99	1.05
		Dihydroquercetin 3-O-rhamnoside	1.21 ± 0.37	−3.72	−1.56	2.16
	Flavanols	Theaflavin	1.21 ± 0.34	−21.79	−18.84	2.96
	Flavanones	Eriodictyol	1.22 ± 0.34	−1.60	7.36	8.97
		Eriodictyol 7-O-glucoside	1.21 ± 0.37	−3.72	−1.56	2.16
	Flavones	Cannflavin A	1.21 ± 0.34	1.13	−1.36	−2.49
		Chrysoeriol 7-O-(6″-malonyl-glucoside)	1.21 ± 0.33	−7.01	−0.43	6.58
		Luteolin 7-O-glucuronide	1.21 ± 0.33	−21.43	−1.39	20.04
		Cirsimaritin	1.20 ± 0.27	−0.16	−2.97	−2.80
	Flavonols	Quercetin 3-O-xylosyl-glucuronide	1.23 ± 0.28	−1.92	16.55	18.47
		Kaempferol 3-O-(2″-rhamnosyl−6″-acetyl-galactoside) 7-O-rhamnoside	1.22 ± 0.31	−2.21	16.25	18.45
		Quercetin 3-O-xylosyl-rutinoside	1.21 ± 0.35	−3.42	−0.97	2.45
		Kaempferol 3-O-glucuronide	1.21 ± 0.33	−21.41	−1.39	20.02
		Kaempferide	1.21 ± 0.33	−10.61	−7.96	2.65
		Myricetin	1.20 ± 0.27	17.61	−4.19	−21.80
	Isoflavonoids	Glycitin	1.22 ± 0.32	−3.02	7.17	10.19
		6″-O-Malonylgenistin	1.20 ± 0.32	−5.45	−4.09	1.36
Phenolic acids	Hydroxybenzoic acids	Protocatechuic acid / 3,5-Dihydroxybenzoic acid	1.22 ± 0.34	19.83	−1.75	−21.58
	Hydroxycinnamic acids	p-Coumaroylquinic acid/3-p-Coumaroylquinic acid/4-p-Coumaroylquinic acid/5-p-Coumaroylquinic acid	1.22 ± 0.33	−3.97	−0.78	3.18
		Stigmastanol ferulate	1.20 ± 0.44	−2.85	1.85	19.70
		3,5-Dicaffeoylquinic acid/4,5-Dicaffeoylquinic acid/3,4-Dicaffeoylquinic acid	1.20 ± 0.33	−4.09	−1.86	2.23