Table 7.

Phenolic compounds identified in Parthenium genus and members of the Asteraceae family screened in leaf and twig extracts of guayule by HPLC-DAD.

		Rt (min)	λ (nm)	References
1	Gallic acid	6.76	280	[23,45,46]
2	Pyrogallol	7.77	280	[45]
3	Chlorogenic acid	11.27	280; 330; 350	[12,24,33,46,47,48]
4	Catechin	11.47	280	[12,47,49]
5	Criptochlorogenic acid	11.57	280; 330; 350	[48]
6	Vanillic acid	14.18	280	[23,31,45,50]
7	Isovanillic acid	14.25	280	[12]
8	Caffeic acid	14.29	280; 330; 350	[23,31,45,48,49,50]
9	Syringic acid	14.85	280	[51,52]
10	Cynarin	16.4	280, 330,350	[12,47,53]
11	p-Coumaric acid	20.00	280; 330; 350	[23,48,50]
12	Rutin	20.27	280; 330; 350	[24,46,47]
13	Verbascoside	21.42	280; 330; 350	[26]
14	Luteolin 7-O-β-D-glucoside	21.61	280; 330; 350	[45,49]
15	Sinapic acid	21.88	280; 330; 350	[20]
16	Ferulic acid	21.98	280; 330; 350	[23,50]
17	1,5-Di-caffeoylquinic acid	24.19	280; 330; 350	[12,31,47,53]
18	3,5-Di-caffeoylquinic acid	24.37	280; 330; 350	[12,31,47,53]
19	Chicoric acid	24.18	280; 330; 350	[20]
20	Myricetin	27.40	280; 330; 350	[24]
21	3,4-DMCA	30.95	280; 330; 350	[20]
22	Luteolin	34.01	280; 330; 350	[33,45]
23	Quercetin	34.21	280; 330; 350	[33,46]
24	Cinnamic acid	35.52	280	[26]
25	Apigenin	37.31	280; 330; 350	[20,33]
26	Naringenin	37.41	280; 330; 350	[52]
27	Kaempferol	38.06	280; 330; 350	[11,24]
28	Mangostin	45.5	280; 330; 350	[54]