A new flavonol glycoside from the flowers of <i>Hosta plantaginea</i> with cyclooxygenases-1/2 inhibitory and antioxidant activities

Abstract

<i>Hosta plantaginea</i> was a traditional Chinese medicinal plants used to treat inflammatory and painful diseases with partial scientific validation. Solvent extractions followed by repeated chromatographic purification of the <i>H. plantaginea</i> flowers led to the isolation of one new flavonoid glycoside, hostaflavone A (<b>1</b>), together with one related known compound, kaempferol-3-<i>O</i>-sophoroside-7-<i>O</i>-glucoside (<b>2</b>), and their structures were elucidated on the basis of chemical and spectral evidence, as well as by comparison with literature data. Compounds <b>1</b> and <b>2</b> were evaluated for the anti-inflammatory activites against cyclooxygenases (COX-1 and COX-2) and DPPH free radical-scavenging activities <i>in vitro</i>. The results revealed that <b>1</b> and <b>2</b> exhibited significant COX-1 inhibition and moderate COX-2 inhibition compared to the reference celecoxib. Additionally, <b>1</b> and <b>2</b> displayed insignificant antioxidant activities compared to the positive control L-ascorbic acid.