Study On Anti-Inflammatory Chemical Constituents From Artemisia Scoparia Waldst.Et Kit.

Artemisiae Scopariae Herba (ASH) is the dried aerial parts of Artemisia scoparia Waldst.et Kit. or Artemisia capillaris Thunb. from Family Asteraceae. It can clear heat and promote dieresis, cure jaundice by normalizing functioning of the gallbladder. As one of the most commonly used Traditional Chinese Medicines (TCMs), ASH plays a key role in the classic formulas like Yinchenhao Tang. Previous research have indicated the anti-inflammatory activity of the extract from Artemisia scoparia Waldst.et Kit. (AS), while the active constituents have not been reported. Moreover, the formula granules of TCMs had been used clinically with argument and controversy due to the lack of fundamental research. The aqueous extract from AS have been used as the formula granules of ASH clinically.Therefore, systematically study of the anti-inflammatory active chemical constituents of the aqueous extracts from AS were carried out.The preliminary isolation method of the aqueous extract from AS by using macroporous resin was determined under the guidance of UPLC analysis. Under the elution by gradient ethanol solution (0%,10%,30%,50%, and 100% ethanol parts), the aqueous extract from AS was separated into 5 parts. The anti-inflammatory activity of the 5 parts mentioned above was evaluated by the LPS-induced RAW264.7 macrophage cells model. The results showed that the 50% and 100% ethanol parts can significantly reduce inflammatory mediators nitric oxide (NO) by 83.8% and 58.6% under the safe dose 40μg·L-1, respectively. Thus, the anti-inflammatory active fractions of the formula granules of ASH were 50% and 100% ethanol parts.The chemical constituents of the anti-inflammatory active fractions from the aqueous extract of AS were systematically studied. The compounds were isolated and purified by recrystallization and various column chromatographies including macroporous resin, silica gel, Sephadex LH-20, and semi-preparative HPLC. Their structures were identified on the basis of spectroscopic methods and physicochemical characteristics.15 compounds were isolated from the anti-inflammatory fractions and were identified as 4’-hydroxyacetophenone (YC-1),2,5-dihydroxycinnamic acid ethyl ester (YC-2), quercetin (YC-3), luteolin(YC-4),7S,8R-dihydrodehydroconiferyl alcohol (YC-5), prudomestin (YC-6),7,4’-dimethoxykaempferol (YC-7), 95,12S,13S-trihydroxy-10E-octadecenoate (YC-8),6-O-(E)-caffeoyl-hydroxy-phenethylalcohol-4’-O-β-D-glucopyranoside(YC-9),6-O-(E)-caffeoyl-p-hydr-oxyacetophenone-4’-O-β-D-glucopyranoside (YC-10), isorhmnetin-4’-O-β-D-glucoside (YC-11), kaempferol-3-O-β-D-glucoside (YC-12), quercetin-7-O-α-L-rhamnoside (YC-13), stearic acid (YC-14) and β-daucosterol (YC-15), respectively. All the compounds were obtained from the formula granules of Artemisiae Scopariae Herba for the first time, among them, compounds YC-8, YC-11, YC-12 were isolated from genus Artemisia for the first time, and compounds YC-2, YC-5, YC-9, YC-10 were obtained from Artemisia scoparia Waldst. et Kit for the first time.Based on the chemical studies, the anti-inflammatory effect of 12 compounds isolated before were evaluated by the LPS-induced RAW264.7 macrophage cells model. The results indicated that all the tested compounds exhibited inhibition of NO production stimulated by LPS in RAW264.7 macrophage cells at different extent, among them, quercetin-7-O-α-L-rhamnoside (YC-13) show the best effect with IC50 value of 7.89 μM.