Chemical constituents and their antioxidant and anti-inflammatory activities from edible Cornus officinalis fruits

Cornus officinalis fruits, an edible functional food with the tonic effect, belongs to the Cornaceae family. It is widely used in both traditional medicine and in some food production. A phytochemical study on the fruits of Cornus officinalis resulted in 20 structurally diverse compounds including 2 new lignans, named officinalignans A-B (1-2), and 2 new iridoids, named loganin-(4'-O-7 '')-alpha-morroniside (3) and 2'-O-p-coumaroyl-kingiside (4). These structures were identified by various spectroscopic techniques and chemical methods, including NMR, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), CD spectra and acid hydrolysis. The radical scavenging effects of all isolates were investigated. Compounds 1, 4, 15 and 18 showed significant inhibitory activities against 2,2-diphenyl-1-picrylhydrazyl (DPPH), whereas 7 and 17 displayed good 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical-scavenging activities that was even more potent than that of trolox. In addition, all isolates were evaluated for their anti-inflammatory activities by detecting the nitric oxide (NO), tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) production by the lipopolysaccharides (LPS) in macrophages cell line RAW264.7, and compounds 3-4 and 6-7 exhibited the potent inhibition. The results disclosed that the lignans and iridoids from C. officinalis fruits can be regarded as a potential new source of antioxidants and inflammation inhibitors. [GRAPHICS] .