Objective To study the chemical constituents, antioxidant activity and anti-inflammatory activity of the n-butanol fraction from Primulina eburnea. Methods Compounds were separated and purified using chromatographic techniques such as normal-phase and reversed-phase silica gel column chromatography, Sephadex LH-20 gel column chromatography and RP-HPLC. Meanwhile, their structures were identified by spectroscopic techniques including NMR, UV and IR. Subsequently, the antioxidant activities of obtained compounds were evaluated by the DPPH and ABTS assays, while the Griess assay was employed to determine the effect of these compounds on NO production in lipopolysaccharide (LPS)-induced RAW264.7 cells to assess their anti-inflammatory activity. Results A total of 20 compounds were isolated from the n-butanol fraction of P. eburnea and were respectively identified as spathodic acid-28-O-β-D-gentiobioside (1), calceolarioside B (2), 2-(3,4-dihydroxyphenyl)ethanol glucoside (3), salidroside (4), tyrosol (5), 6-hydroxyapigenin-7-O-β-[2-O-β-xyloglucoside] (6), icariol A₂(7), (+)-isolariciresinol (8), 5-methoxy-(+)-isolariciresinol (9), (+)-syringaresinol-4'-O-β-D-glucopyranoside (10), dihydrophaseic acid (11), (6S,9R)-roseoside (12), esculetin (13), p-hydroxybenzoic acid (14), protocatechuic acid (15), vanillic acid (16), syringic acid (17), caffeic acid (18), caffeic acid methyl ester (19) and methyl-3-O-β-D-glucopyranosyl-4-hydroxy caffeic acid (20). Meanwhile, compounds 7, 17 and 18 exhibited significant antioxidant activity. Compounds 3, 5—9 exhibited significant inhibitory effects on the production of NO in LPS-induced RAW264.7 cells. Conclusion Compound 1 is a new triterpenoid glycoside, named eburneoside A. While compounds 4, 6, 9—12, 14, 15 and 20 were isolated for the first time from the genus Primulina. Additionally, compounds 17 and 18 were firstly isolated from P. eburnea. Furthermore, some of these compounds exhibited significant antioxidant and anti-inflammatory activities.

Gesneriaceae  /  Primulina eburnea (Hance) Yin Z. Wang  /  triterpenoid glycoside  /  antioxidant activity  /  anti-inflammatory activity  /  eburneoside A  /  salidroside  /  icariol A₂  /  syringic acid