Antioxidant and tyrosinase inhibitory effects of neolignan glycosides from Crataegus pinnatifida seeds.
In our efforts to find an inhibitor of melanin formation and develop potential depigmenting agents for skin-protecting cosmetics and medicinal products from natural resources, we focused on the seeds of Crataegus pinnatifida which showed antioxidant and tyrosinase-inhibiting activities. By activity-guided fractionation of an extract of C. pinnatifida seeds, four new neolignan glycosides, pinnatifidaninsides A-D (1-4), along with two known compounds (5-6), were isolated. Their structures were elucidated by spectroscopic analyses, especially 1D, 2D NMR and CD spectra. The antioxidant and tyrosinase-inhibiting activities of all isolates were assayed. Compound 6 showed good activity against 2,2-diphenyl-1-pikrylhydrazyl, while compounds 1, 2, 5, and 6 exhibited strong 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) free radical scavenging activity, being as effective as, or even more effective than the positive control Trolox. Moreover, compounds 5 and 6 displayed a moderate mushroom tyrosinase inhibitory activity.
Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang, P. R. China.
Xiao-Xiao
XX
Huang
Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang, P. R. China.
Qing-Bo
QB
Liu
Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang, P. R. China.
Jie
J
Wu
Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang, P. R. China.
Li-Hong
LH
Yu
Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang, P. R. China.
Qian
Q
Cong
School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang, P. R. China.
Yan
Y
Zhang
Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang, P. R. China.
Li-Li
LL
Lou
Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang, P. R. China.
Ling-Zhi
LZ
Li
Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang, P. R. China.
Shao-Jiang
SJ
Song
D000975:Antioxidants / Q000494:pharmacology*; D027825:Crataegus / Q000737:chemistry*; D004353:Drug Evaluation, Preclinical / Q000379:methods; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D006027:Glycosides / Q000737:chemistry*; D017705:Lignans / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D012639:Seeds / Q000737:chemistry; D013329:Structure-Activity Relationship
D000975:Antioxidants; D004791:Enzyme Inhibitors; D006027:Glycosides; D017705:Lignans; D014442:Monophenol Monooxygenase