Influence of alcoholic solid- state fermentation process on bioactive constituents and antioxidant activity from mulberries( Morus nigra L.)

The aim of the present study was to evaluate the changes of contents of total phenol,flavonoids and anthocyanins from sun- dried mulberry( Morus nigra L.) and their antioxidant activities( DPPH,FRAP,ABTS) during fermentation process. The result showed that the total phenol was increased with the 10 days prefermentation period,while the contents of flavonoids and anthocyanins were gradually decreased. The antioxidant activity,showing a trend of a rise at first followed by a decline,was reduced by nearly 50% after the end of fermentation.The methods of DPPH and FRAP radical scavenging activities were more suitable for displaying the variation of antioxidative capacity of fermented mulberry wine than the method of ABTS radical scavenging activities.After the end of fermentation,14.21 g / kg of reducing sugar,101.6 g / kg concentration of ethanol,2.124 g / kg of total phenol,579.4 mg / kg of anthocyanins,41.2 g / kg of flavonoids,21.1% of DPPH radical scavenging rate,40.9 μmol Fe²⁺/ L of FRAP antioxidant activity and 23.241 g / L of total extracts were obtained,which provided a feasible way to further develop high biological activity and deeply processed products of mulberries.