Erigeron annuus Protects PC12 Neuronal Cells from Oxidative Stress Induced by ROS-Mediated Apoptosis

Table 3

Retention time and calibration curves of standards (n = 3).

Number	Phenolic compounds	Rt^a (min)	R^2b	Calibration curve^c (Y = aX + b)
1	Homogentisic acid	5.07	1.00	Y = 15266X − 261028
2	Gallic acid	6.37	0.99	Y = 12344X − 257389
3	Protocatechnic acid	7.67	1.00	Y = 17658X − 339681
4	Chlorogenic acid	10.16	1.00	Y = 21148X − 461992
5	(+)-Catechin	10.26	1.00	Y = 3427.1X − 41775
6	Caffeic acid	12.49	1.00	Y = 45912X − 904096
7	Phloretic acid	15.58	0.99	Y = 6986.6X − 173117
8	p-Coumaric acid	16.95	1.00	Y = 109086X − 2095025
9	Ferulic acid	18.92	1.00	Y = 52036X − 996550
10	Veratric acid	19.76	1.00	Y = 12550X − 234385
11	Salicylic acid	21.13	1.00	Y = 5350X − 102288
12	Naringin	22.25	0.99	Y = 11740X − 158668
13	Hesperidin	23.12	1.00	Y = 3197X − 57859
14	Quercetin	30.61	1.00	Y = 11756X − 257156
15	Cinnamic acid	31.90	1.00	Y = 112897S − 2E + 06
16	Naringenin	33.88	0.99	Y = 47325X − 691049
17	Kaempferol	34.69	1.00	Y = 27333X − 605965
18	Hesperitin	34.97	0.99	Y = 31446X − 426773

^aRt: retention time; ^bcorrelation coefficients for three data points in the calibration curve; ^cwhere the Y and X are the peak area and concentration of the analyses (μg/mL), respectively.