Wheat germ is rich in quinones that exist as glycosides. In this study, we used Celluclast 1.5L to release the hydroxyquinones, which turn into benzoquinone, and prepared the water extract from enzyme-treated wheat germ (EWG). We investigated whether enzyme treatment altered the anti-inflammatory activity compared to the water extract of untreated wheat germ (UWG). UWG inhibited the production of inducible nitric oxide synthase (iNOS) and interleukin (IL)-12 and induced the production of IL-10 and heme oxygenase (HO)-1 in lipopolysaccharide (LPS)-stimulated macrophages. Enzyme treatment resulted in greater inhibition of iNOS and IL-10 and induction of HO-1 compared to UWG, possibly involving the modulation of nuclear factor (NF)-κB, activator protein 1 (AP-1) and nuclear factor erythroid 2-related factor (Nrf2). Mice fed UWG or EWG had decreased serum tumor necrosis factor (TNF)-α and increased serum IL-10 levels after intraperitoneal injection of LPS, with UWG being more effective for IL-10 and EWG more effective for TNF-α. Hepatic HO-1 gene was only expressed in mice fed EWG. We provide evidence that enzyme treatment is a useful biotechnology tool for extracting active compounds from wheat germ.
Keywords: benzoquinone; enzyme; inflammation; macrophages; wheat germ.