Chemical composition and bioactivity changes in stale rice after fermentation with Cordyceps sinensis

Stale rice is typically discarded as waste because it has low eating quality as well as low nutritional and biofunctional values resulting from long-time storage. After solid-state fermentation with Cordyceps sinensis, fermented stale rice (FSR) grains contained higher amount of protein, carbohydrate, lipid, dietary fibre, vitamin E, β-glucan, amino acids and ergosterol than non-fermented stale rice. It also exhibited increased superoxide dismutase activity. When mice were administrated with powdered FSR in 1% carboxymethyl cellulose sodium salt solution (FSR-CMC-Na), increases in monoamine oxidase B (MAO-B) in brain, lipid peroxides (LPOs) in liver, and myocardial lipofuscin related to aging were inhibited, while the activity of MAO-B in liver was not significantly changed. The results suggest that solid-state fermentation of low-valued or waste stale rice could produce an important bioresource to develop bioactive food materials.