Optimization of extraction conditions and enhancement of phenolic content and antioxidant activity of pearl millet fermented with Aspergillus awamori MTCC-548

摘要

Abstract The present study envisaged two stage optimization of conditions using {RSM} for extraction of total phenolic compounds from pearl millet koji prepared with Aspergillus awamori. Antioxidant activity was determined by employing {DPPH} and radical cation of ABTS. In phase-1, fermentation time (5–8 days), extraction temperature (40–60?°C), extraction time (45–60?min.) and solvent (ethanol, 50%; 0.5?ml HCL?+?99.5?ml methanol) were tested for maximizing extraction process. The optimum conditions of phenolic recovery were achieved at 8 days fermentation time, 40?°C extraction temperature, 45?min. extraction time with 50% ethanol as solvent, with values of 169.19?mg GAE/g for TPC, 262.7 {VCEAC} μmol/g for {DPPH} and 281.86 {VCEAC} μmol/g for ABTS. {TPC} were found to be positively correlated (p?