ANTIOXIDANT PROPERTIES OF ETHANOLIC AND METHANOLIC EXTRACTS FROM MONASCUS‐FERMENTED SOYBEANS

Soybeans are very common foods in oriental countries used as a meat substitute. Monascusspecies possess functional components and have been used on traditional fermented food. Solid-state fermentation of the soybean substrate by Monascus species is a new area of investigation. In the present study, methanolic extracts from three samples exhibited better antioxidant activity in the conjugated diene method, reducing power, scavenging ability on 1,1-diphenyl-2-picrylhydrazyl radicals and chelating ability on ferrous ions. Monascus species inoculated onto the soybean substrate contributed higher reducing power, scavenging and chelating abilities and higher amounts of phenol components than uninoculated soybean product. Overall, Monascus-fermented soybeans showed better antioxidant properties and can be developed as a new dietary supplement and functional food. PRACTICAL APPLICATION Soybeans and soy products are rich in isoflavones and are very common foods used as a meat substitute in oriental countries. Fungus Monascus has been used as a traditional fermented food and its metabolic products are also utilized as food pigments or biological agents in oriental countries for centuries. Many reporters showed that soy isoflavone aglycones and Monascus spp. metabolite exhibited physiological activities. In addition, previous studies showed a fermentation process using microorganisms to inoculate onto a nonsoluble material that can produce chemicals and enzymes. Therefore, the ethanolic and methanolic extracts from Monascus-fermented soybeans were evaluated for antioxidant properties, and the information obtained would be more valuable than that from soybeans to develop new functional foods.