Polyphenols extracted from huangjiu have anti-inflammatory activity in lipopolysaccharide stimulated RAW264.7 cells

In the present study, an extraction method, combining extraction by ethyl acetate + ethanol and purification by HPD400 resin, was established to obtain huangjiu polyphenol extract (HPE). After extraction and purification, the polyphenol yield was 22.57%, and 90.57% protein and 97.99% sugar were removed. HPLC analysis indicated that (+)-catechin (91.33 μg mL^-1) was the predominant phenolic compound among the 11 detected polyphenols. In LPS-stimulated RAW264.7 cells, HPE exhibits anti-inflammatory effects by inhibiting the production of NO and pro-inflammatory cytokines (TNF-α, interleukin IL-6 and IL-1β). The anti-inflammatory effect of HPE is associated with the inhibition of iNOS expression, the suppression of NF-κB translocation to the nucleus, and the inhibition of the phosphorylation of IκB and the MAPK family proteins, e.g. p-38, Erk 1/2, and JNK. Moreover, the activation of Nrf2 and HO-1 is also related to the anti-inflammatory effect of HPE.