Table 3. Characterization of Phenolic Compounds in Lotus by Using LC-ESI-QTOF-MS/MS^a.

no.	proposed compounds	molecular formula	RT (min)	ionization mode	molecular weight	theoretical (m/z)	observed (m/z)	mass error (ppm)	MS/MS product ions	samples
Phenolic acid
	hydroxybenzoic acids
1	galloyl glucose	C13H16O10	10.541	[M – H]−	332.0743	331.0670	331.0668	–0.60	169, 125	LSE
2	2-hydroxybenzoic acid	C7H6O3	11.038	c[M – H]−	138.0317	137.0244	137.0248	2.92	93	LRP, LR, LSC,bLSE, LRK
3	4-hydroxybenzoic acid 4-O-glucoside	C13H16O8	11.054	[M – H]−	300.0845	299.0772	299.0770	–0.67	255, 137	LR,bLSE, LRK
4	gallic acid	C7H6O5	12.893	[M – H]−	170.0215	169.0142	169.0140	–1.18	125	LSC,bLSE
5	paeoniflorin	C23H28O11	34.596	c[M – H]−	480.1632	479.1559	479.1583	5.00	449, 357, 327	LSC,bLSE
	hydroxycinnamic acids
6	cinnamic acid	C9H8O2	12.479	c[M – H]−	148.0524	147.0451	147.0453	1.36	103	LRP, LR, LSC,bLSE
7	3-p-coumaroylquinic acid	C16H18O8	13.543	c[M – H]−	338.1002	337.0929	337.0921	–2.37	265, 173, 162	bLRP, LR, LSE, LRK
8	m-coumaric acid	C9H8O3	39.486	c[M – H]−	164.0473	163.0401	163.0405	3.03	119	LRP, LR,bLSC, LSE, LRK
9	caffeoyl glucose	C15H18O9	19.603	[M – H]−	342.0951	341.0878	341.0875	–0.88	179, 161	LSE
10	caffeic acid	C9H8O4	19.619	[M – H]−	180.0423	179.0350	179.0350	0.00	143, 133	LSE
11	3-feruloylquinic acid	C17H20O9	20.847	c[M – H]−	368.1110	367.1034	367.1025	–2.45	298, 288,192, 191	bLSE, LRK
12	ferulic acid 4-O-glucoside	C16H20O9	23.330	[M – H]−	356.1107	355.1034	355.1031	–0.84	193, 178, 149, 134	LR, LSC,bLSE
13	isoferulic acid	C10H10O4	23.344	c[M – H]−	194.0579	193.0506	193.0513	3.63	178, 149, 134	LRP, LR, LSC,bLSE, LRK
14	p-coumaric acid 4-O-glucoside	C15H18O8	23.754	[M – H]−	326.1002	325.0929	325.0940	3.38	163	bLR, LSE
15	sinapic acid	C11H12O5	26.118	c[M – H]−	224.0685	223.0612	223.0618	2.69	205, 163	LR,bLSC, LSE, LRK
16	verbascoside	C29H36O15	31.531	[M – H]−	624.2054	623.1981	623.1984	0.48	477, 461,315, 135	LSE
17	1-sinapoyl-2-feruloylgentiobiose	C33H40O18	60.158	[M – H]−	724.2215	723.2142	723.2122	–2.77	529, 499	LSE
	hydroxyphenylacetic acids
18	3,4-dihydroxyphenylacetic acid	C8H8O4	14.119	c[M – H]−	168.0423	167.0350	167.0346	–2.39	149, 123	LRP, LR, LSC,bLSE, LRK
19	2-hydroxy-2-phenylacetic acid	C8H8O3	14.616	c[M – H]−	152.0473	151.0400	151.0394	–3.97	136, 92	LRP, LSC,bLSE, LRK
	hydroxyphenylpentanoic acids
20	3-hydroxy-3-(3-hydroxyphenyl)propionic acid	C9H10O4	18.327	[M – H]−	182.0579	181.0506	181.0507	0.55	163, 135, 119	LSE
Flavonoids
	flavanols
21	(+)-catechin 3-O-gallate	C22H18O10	10.942	[M – H]−	442.0900	441.0827	441.0842	3.40	289, 169, 125	LRK
22	(+)-gallocatechin 3-O-gallate	C22H18O11	11.106	c[M – H]−	458.0849	457.0776	457.0781	1.10	305, 169	LSE
23	(−)-epigallocatechin	C15H14O7	21.832	c[M – H]−	306.0740	305.0667	305.0675	2.62	261, 219	LRP, LSC,bLR
24	procyanidin trimer C1	C45H38O18	22.246	c[M – H]−	866.2058	865.1985	865.1989	0.46	739, 713, 695	LRP,b LR, LSC
25	cinnamtannin A2	C60H50O24	24.081	c[M – H]−	1154.2692	1153.2619	1153.2656	3.21	739	LR,bLSC
26	(−)-epicatechin	C15H14O6	24.208	c[M – H]−	290.0790	289.0717	289.0714	–1.04	245, 205, 179	LRP, LR, LRK, LSC,bLSE
27	4″-O-methylepigallocatechin 3-O-gallate	C23H20O11	32.575	c[M – H]−	472.1006	471.0933	471.0927	–1.27	169, 319	LRP, LSC,bLSE
28	procyanidin dimer B1	C30H26O12	78.369	c[M – H]−	578.1424	577.1351	577.1340	–1.90	451	bLRP, LR, LSC, LRK
	flavanones
29	eriocitrin	C27H32O15	34.931	c[M – H]−	596.1741	595.1668	595.1650	–3.00	431, 287	bLSC, LSE
30	naringin	C27H32O14	41.624	c[M – H]−	580.1792	579.1719	579.1696	–4.00	271	bLRP, LSE
31	8-prenylnaringenin	C20H20O5	45.721	[M + H]+	340.1311	341.1384	341.1389	1.47	323, 137	bLRP, LR, LRK
32	hesperidin	C28H34O15	52.573	[M + H]+	610.1898	611.1971	611.1962	–1.47	593, 465, 449, 303	LSE
33	hesperetin 3′-O-glucuronide	C22H22O12	52.779	c[M – H]−	478.1111	477.1038	477.1048	2.10	301, 175, 113, 85	LRP,bLR, LSE, LRK
	flavones
34	apigenin 7-O-apiosyl-glucoside	C26H28O14	14.031	c[M + H]+	564.1479	565.1552	565.1552	0.00	296	LR,bLSE
35	apigenin 7-O-glucuronide	C21H18O11	22.201	[M + H]+	446.0849	447.0922	447.0933	2.46	271, 253	bLRP, LR
36	apigenin 6,8-di-C-glucoside	C27H30O15	32.309	c[M – H]−	594.1585	593.1512	593.1532	3.37	503, 473	LSC,bLSE
37	chrysoeriol 7-O-glucoside	C22H22O11	40.657	c[M + H]+	462.1162	463.1235	463.1221	–3.00	445, 427, 409, 381	LSE
38	apigenin 6-C-glucoside	C21H20O10	41.736	c[M – H]−	432.1056	431.0983	431.0984	0.23	413, 341, 311	LR, LRP, LSC,bLSE
39	neodiosmin	C28H32O15	52.580	c[M + H]+	608.1741	609.1814	609.1826	1.97	301, 286	bLSC, LSE
	flavonols
40	patuletin 3-O-glucosyl-(1->6)-[apiosyl(1->2)]-glucoside	C33H40O22	21.872	[M – H]−	788.2011	787.1938	787.1907	–3.94	625, 463, 301, 271	LSE
41	quercetin 3-O-xylosyl-rutinoside	C32H38O20	26.493	[M + H]+	742.1956	743.2029	743.2058	3.90	479, 317	LSC
42	myricetin 3-O-rutinoside	C27H30O17	27.025	c[M – H]−	626.1483	625.1410	625.1393	–2.72	301	LSC,bLSE
43	quercetin 3-O-glucosyl-xyloside	C26H28O16	27.754	c[M – H]−	596.1377	595.1304	595.1306	0.34	265, 138, 116	LSC,bLSE
44	kaempferol 3,7-O-diglucoside	C27H30O16	28.897	c[M – H]−	610.1534	609.1461	609.1479	2.95	447, 285	LSC,bLSE
45	myricetin 3-O-glucoside	C21H20O13	38.995	c[M – H]−	480.0904	479.0831	479.0834	0.63	317	LRP,bLR, LSC, LRK
46	kaempferol 3-O-glucosyl-rhamnosyl-galactoside	C33H40O20	40.180	c[M – H]−	756.2113	755.2040	755.2025	–2.00	285	LSC
47	kaempferol 3-O-(2″-rhamnosyl-galactoside) 7-O-rhamnoside	C33H40O19	41.143	[M – H]−	740.2164	739.2091	739.2106	2.03	593, 447, 285	bLRP, LSE
48	quercetin 3′-O-glucuronide	C21H18O13	45.016	[M – H]−	478.0747	477.0674	477.0653	–4.40	301	LSC,bLSE
49	myricetin 3-O-rhamnoside	C21H20O12	45.314	c[M – H]−	464.0955	463.0882	463.0871	–2.38	317	LRP, LR, LSC,bLSE, LRK
50	quercetin 3-O-arabinoside	C20H18O11	45.598	c[M – H]−	434.0849	433.0776	433.0780	0.90	301	LRP,bLR, LSE
51	isorhamnetin	C16H12O7	85.555	c[M – H]−	316.0583	315.0510	315.0510	0.00	300, 271	LSC,bLSE
	dihydrochalcones
52	3-hydroxyphloretin 2′-O-xylosyl-glucoside	C26H32O15	12.115	[M – H]−	584.1741	583.1668	583.1688	3.43	289	LSE
53	3-hydroxyphloretin 2′-O-glucoside	C21H24O11	38.973	c[M – H]−	452.1319	451.1246	451.1247	0.22	289, 273	LRP, LSC,bLRK
54	phloridzin	C21H24O10	47.041	c[M – H]−	436.1369	435.1296	435.1303	1.61	273	LRP, LR,bLRK
	anthocyanins
55	peonidin 3-O-diglucoside-5-O-glucoside	C34H43O21	10.988	c[M + H]+	787.2297	788.2370	788.2399	3.68	625, 478, 317	bLRP, LR, LSE
56	cyanidin 3-O-(6″-p-coumaroyl-glucoside)	C30H27O13	16.009	c[M + H]+	595.1452	596.1525	596.1515	–1.68	287	bLR, LRP
57	delphinidin 3-O-glucoside	C21H21O12	22.187	c[M + H]+	465.1033	466.1106	466.1095	–2.36	303	LRP,bLR, LSC, LSK
58	delphinidin 3-O-glucosyl-glucoside	C27H31O17	26.933	[M + H]+	627.1561	628.1634	628.1664	4.78	465, 303	LSE
59	isopeonidin 3-O-arabinoside	C21H21O10	41.565	[M + H]+	433.1135	434.1208	434.1200	–1.84	271, 253, 243	bLSC, LSE
60	cyanidin 3,5-O-diglucoside	C27H31O16	42.675	c[M + H]+	611.1612	612.1685	612.1672	–2.12	449, 287	bLSC, LSE
61	pelargonidin 3-O-rutinoside	C27H31O14	50.950	[M + H]+	579.1714	580.1787	580.1814	4.65	271, 433	LSE
	isoflavonoids
62	6″-O-malonylglycitin	C25H24O13	37.252	[M + H]+	532.1217	533.1290	533.1274	–3.00	285, 270, 253	LSE
63	5,6,7,3′,4′-pentahydroxyisoflavone	C15H10O7	37.837	c[M + H]+	302.0427	303.0500	303.0503	0.99	285, 257	bLRP, LR, LSC, LSE, LRK
64	6″-O-acetyldaidzin	C23H22O10	41.868	c[M – H]−	458.1213	457.1140	457.1129	–2.41	221	LRP, LR, LSC,bLSE
65	violanone	C17H16O6	47.057	cM – H]−	316.0947	315.0874	315.0881	2.22	300, 285, 135	LRP, LR, LSE,bLRK
66	3′-hydroxydaidzein	C15H10O5	50.933	[M + H]+	270.0528	271.0601	271.0613	4.43	253, 241, 225	LRP, LR, LSC,bLSE
67	6″-O-acetylglycitin	C24H24O11	50.950	c[M + H]+	488.1319	489.1392	489.1410	3.68	285, 270	bLSE, LRP
68	3′-hydroxygenistein	C15H10O6	51.305	c[M + H]+	286.0477	287.0550	287.0546	–1.39	269, 259	LSC, LSE,bLRK
69	dihydrobiochanin A	C16H14O5	54.847	[M + H]+	286.0841	287.0914	287.0922	2.79	269, 203,201, 175	LRP
70	2-dehydro-O-desmethylangolensin	C15H12O4	75.685	c[M – H]−	256.0736	255.0663	255.0655	–3.14	135, 119	LRP,bLRK
71	3′,4′,7-trihydroxyisoflavanone	C15H12O5	83.053	c[M – H]−	272.0685	271.0612	271.0608	–1.48	177, 151, 119, 107	LRP, LR, LSC,bLSE, LRK
Other polyphenols
	hydroxycoumarins
72	coumarin	C9H6O2	8.486	[M + H]+	146.0368	147.0441	147.0442	0.68	103, 91	LRP
73	esculin	C15H16O9	13.406	[M + H]+	340.0794	341.0867	341.0862	–1.47	179, 151	bLRP, LR, LSC
74	salvianolic acid B	C36H30O16	27.074	[M – H]−	718.1534	717.1461	717.1485	3.35	519, 339, 321, 295	LSE
75	scopoletin	C10H8O4	41.480	c[M – H]−	192.0423	191.0350	191.0357	3.66	176	LRP,bLR, LRK
	alkylmethoxyphenols
76	4-vinylsyringol	C15H14O3	21.803	c[M + H]+	242.0943	243.1016	243.1019	1.23	225, 211, 197	bLRP, LSE
	hydroxybenzoketones
77	2,3-dihydroxy-1-guaiacylpropanone	C10H12O5	9.879	c[M – H]−	212.0685	211.0612	211.0602	–4.70	167, 123, 105, 93	LRP
78	2-hydroxy-4-methoxyacetophenone 5-sulfate	C9H10O7S	12.844	[M – H]−	262.0147	261.0074	261.0069	–1.92	181, 97	LSE
	tyrosols
79	hydroxytyrosol 4-O-glucoside	C14H20O8	9.777	c[M – H]−	316.1158	315.1085	315.1076	–2.90	153, 123	bLSC, LR
80	demethyloleuropein	C24H30O13	12.181	[M – H]−	526.1686	525.1613	525.1633	3.81	495	LSE
81	3,4-DHPEA-AC	C10H12O4	37.614	c[M – H]−	196.0736	195.0663	195.0659	–2.05	135	LRP, LR,bLRK
Lignans
82	todolactol A	C20H24O7	39.718	c[M – H]−	376.1522	375.1449	375.1439	–2.67	313, 137	LRP,bLRK
83	7-hydroxymatairesinol	C20H22O7	41.309	c[M – H]−	374.1366	373.1293	373.1298	1.30	343, 313, 298, 285	LR
84	matairesinol	C20H22O6	45.898	[M – H]−	358.1416	357.1343	357.1338	–1.40	342, 327, 313, 221	LRP, LR,bLRK
Stilbenes
85	resveratrol	C14H12O3	31.317	c[M – H]−	228.0786	227.0713	227.0709	–1.80	212, 185, 157, 143	bLRP, LR, LSC, LRK
86	resveratrol 3-O-glucoside	C20H22O8	42.667	[M – H]−	390.1315	389.1242	389.1240	–0.51	227	LRK

^aLotus samples mentioned in abbreviations are lotus rhizome pulp (LR), lotus rhizome peel (LRP), lotus rhizome knot (LRK), lotus seed cotyledon (LSC), and lotus seed embryo (LSE).

^bCompound was detected in more than one lotus sample; data presented in this table are from the asterisk sample.

^cCompounds were detected in both negative [M – H]⁻ and positive [M + H]⁺ modes of ionization, while only single mode data were presented.