Study on production of yellow pigment from potato fermented by Monascus

Abstract

Aiming at the problem of low yield of monascus yellow pigment liquid fermentation, a new process for producing yellow pigment by liquid fermentation of Monascus from potato has been designed. In this process, the color value of intracellular yellow pigment reaches 341.2U/g, which is 58.73% higher than that of conventional liquid fermentation; the color value of extracellular yellow pigment reached 168U/g, which was 38.39% higher than that of conventional liquid fermentation. It was identified by liquid chromatography-mass spectrometry that the intracellular yellow pigments produced by this method were mainly Monascus and Monascus anka. The yields of these two pigments were increased by 33.91% and 84.32%, and their concentrations were 274.6 μg/mL and 167.1 μg/mL, respectively. In addition, the content of citrinin produced by the new process method was 97.85% lower than that of the original Monascus C100 strain and the fermentation broth has good stability. The electronic nose analysis of the fermentation broth indicated that the flavor substances were mainly alcohols and aldehydes and ketones. The antioxidant activity of the fermentation broth is good, for example: the reducing power is comparable to the reducing power of 350 μg/mL VC, the maximum DPPH free radical scavenging rate is 69.81%, the IC50 value of the superoxide anion free radical scavenging rate is 0.873 mL, ABTS The maximum free radical scavenging rate was comparable to the VC scavenging rate of 0.0035 mg/mL, and the maximum scavenging rate of hydroxyl radicals was 87.95%.