Table 4.

Effect of 30 ligands on MC1R content (X  ± SD, n = 6).

Number	Ligands	MC1R (ng/L)	Inhibition (%)
	Control	4.389 ± 0.022	0
1	Licochalcone A	2.590 ± 0.006	40.99
2	Salvianolic acid A	2.652 ± 0.006	39.58
3	Linolenic acid	2.679 ± 0.018	38.97
4	Isochlorogenic acid A	2.703 ± 0.025	38.44
5	Melitose	2.892 ± 0.025	34.13
6	Isorhamnetin-3-O-neohespeidoside	2.924 ± 0.025	33.39
7	Isochlorogenic acid C	3.178 ± 0.019	27.60
8	Platycodin D	3.187 ± 0.018	27.40
9	Palmitoyl tripeptide-1	3.238 ± 0.022	26.25
10	Ginsenoside Rg3	3.285 ± 0.006	25.18
11	Ginsenoside Rb2	3.351 ± 0.007	23.43
12	Matrixyl	3.409 ± 0.003	22.35
13	Aucubin	3.418 ± 0.029	22.15
14	Neohesperidin	3.441 ± 0.018	21.61
15	Argireline	3.471 ± 0.005	20.93
16	Nonapeptide-1	3.569 ± 0.029	18.71
17	Asiaticoside	3.592 ± 0.011	18.17
18	Isoorientin	3.666 ± 0.030	16.49
19	Notoginsenoside R1	3.719 ± 0.006	15.28
20	β-Sitosterol	3.746 ± 0.020	14.67
21	Isoliquiritin	3.758 ± 0.011	14.41
22	Ononin	3.902 ± 0.018	11.11
23	Procyanidin	3.911 ± 0.024	10.91
24	Palmitoyl tetrapeptide-7	3.920 ± 0.011	10.70
25	Aloin	3.923 ± 0.040	10.64
26	(-)-Epigallocatechin gallate (EGCG)	3.926 ± 0.025	10.57
27	Bisdemethoxycurcumin	4.033 ± 0.093	8.14
28	Tannic acid	4.133 ± 0.018	5.86
29	Geniposide	4.287 ± 0.028	2.36
30	α-MSH	4.582 ± 0.015	-4.38

Compared with the control group, *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. Compared with arbutin, ^#P < 0.05, ^##P < 0.01, ^###P < 0.001, ^####P < 0.0001.