Gallic acid (peak 1), catechin (peak 2), chlorogenic acid (peak 3), caffeic acid (peak 4), p-coumaric acid
(peak 5), epicatechin (peak 6), orientin (peak 7), vitexin (peak 8), cyanidin-3-0-glucoside (peak 9), luteolin (peak 10), apigenin (peak 11), and chrysin (peak 12).
Ralph et al., 1994 ) show that the composition of lignin in the cell wall changes during cell development, shifting from highly condensed p-coumaric acid
plus guaiacyl-type monolignols in the middle lamella to predominantly guaiacyl-type lignin through the primary and into the secondary cell wall, and then to syringyl-type lignin in a portion of the primary cell wall, but predominantly in the secondary cell wall.
In this way, compounds 1 to 5 were identified as drabanemoroside , kaempferol 3-O-[alpha]-L-rhamnopyranosyl(1[right arrow]2)- [alpha]-L-rhamnopyranoside , kaempferol , phydroxybenzoic acid , and p-coumaric acid
Chemical analysis of the JW-E JW-E (mg/g) Phenol content (a) 141.02[+ or -]7.36 Proanthocyanidins (b) 297.13[+ or -]19.98 Total anthocyanins (c) 59.62[+ or -]9.13 Hydroxycinnamic acids Syringic acid 8.48[+ or -]0.18 Caffeic acid 6.71[+ or -]0.42 Ferulic acid 1.12[+ or -]0.15 p-Coumaric acid
24.37[+ or -]0.21 Cinnamic acid 0.24[+ or -]0.11 Results are expressed as mean [+ or -] SD of three determinations.
Phenolic acids such as p-coumaric acid
(pCA) and ferulic acid (FA) appear to be important factors in limiting digestion of cell wall polysaccharides by ruminants (Hartley and Ford, 1989).
Aliquots of standard p-coumaric acid
, kaempferol, chlorogenic acid, salicylic acid, rutin and the extracts were applied as spots at the origin on a plate and developed with butanol-acetic acid-water (BAW 4:1:5) in a presaturated chromatographic chamber.
Final concentrations were in the following range: 0.11-1.82 [micro]M for ferulic acid, 1.28-20.40 [micro]M for p-coumaric acid
and 0.08-1.20 [micro]M for trans-cinnamic acid.
The detection of chlorogenic acid, p-coumaric acid
, quercetin, cinnamic acid, kaempferol, chrysin, and artepillin C in BPEE was conducted at 290 nm and the content of each constituent was estimated using its authentic compound.
The main constituents of our propolis sample were isolated and identified: flavonoids are present in small quantities in Brazilian propolis (kaempferid, 5,6,7-trihydroxy-3,4'-dimethoxyflavone, aromadendrine-4'-methyl ether); a prenylated p-coumaric acid
and two benzopyranes: E and Z 2,2-dimethyl-6-carboxyethenyl-8-prenyl-2H-benzopyranes); essential oils (spathulenol, (2Z,6E)-farnesol, benzyl benzoate and prenylated acetophenones); aromatic acids (dihydrocinnamic acid, p-coumaric acid
, ferulic acid, caffeic acid, which are common for poplar propolis, 3,5-diprenyl-p-coumaric acid, 2,2-dimethyl-6-carboxy-ethenyl-8-prenyl-2H-1-benzopyran); di- and triterpenes, among others.
Ursolic acid, oleanolic acid, kaempferol, p-coumaric acid
, FA, rutin, scopolamine lactone, and caffeic acid controls were purchased from Shanghai Yuanye Bio-Technology Co, Ltd, China.
The protection may be attributed to the combined effects of its constituents rather than to any single factor as the leaves are rich in carotenoid content ([beta]-carotene, lutein, Zeaxanthine), ascorbic acid, flavonoids and p-coumaric acid
. Thus Spinacia, showing protection in liver, may prove promising as a rich source of antioxidants because its use is cost-effective, especially for peoples in adverse and hazardous circumstances who are living in poverty.
The antioxidant activity exhibited by small centaury infusion may be due to the presence of several phenolic compounds in this extract, namely esters of p-coumaric acid
, ferulic acid, sinapic acid and kaempferol, which were identified in our previous work (Valentao et al.