DPPH radical scavengers from dried leaves of oregano (Origanum vulgare).
1,1-Dipehnyl-2-picrylhydrazyl (DPPH) radical scavenging activities were found in the extract of dried leaves of oregano (Origanum vulgare). The water-soluble active ingredients were isolated, and their structures were determined to be 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate and 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl 4-O-methylprotocatechuate by (1)H-, (13)C-NMR, DEPT, HMQC, and HMBC spectral analyses, and by NOE experiments. The DPPH radical scavenging activities of these compounds were compared with those of rutin, quercetin and rosmarinic acid at a concentration of 2 x 10(-5) M. The scavenging activity of 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate was almost the same as that of quercetin and rosmarinic acid, but that of 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybennzyl 4-O-methylprotocatechuate was less than that of quercetin, rosmarinic acid and 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate. The amount of 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate was estimated to be 3.8 mg/1 g of dried leaves by an HPLC analysis.
Matsuura
Hideyuki
H
Northern Advancement Center for Science & Technology, Sapporo, Japan. matsuura@chem.agr.hokudai.ac.jp
Chiji
Hideyuki
H
Asakawa
Chikako
C
Amano
Midori
M
Yoshihara
Teruhiko
T
Mizutani
Junya
J
D031162:Achillea; D001713:Biphenyl Compounds; D020844:Comfrey; D016166:Free Radical Scavengers / Q000032:analysis* / Q000302:isolation & purification; D006834:Hydrazines; D031339:Ocimum; D031341:Origanum / Q000737:chemistry*; D028528:Petroselinum; D010851:Picrates; D010936:Plant Extracts / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D013045:Species Specificity; D013055:Spectrophotometry, Infrared
D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D006834:Hydrazines; D010851:Picrates; D010936:Plant Extracts; C004931:1,1-diphenyl-2-picrylhydrazyl