Antioxidant activities and anticancer effects of red yeast rice grown in the medium containing garlic

The effects of culture time on antioxidant and anticancer activities of red yeast rice-garlic (RYRG) ethanol extracts were investigated. RYRG is a product of red yeast rice (Monascus pilosus) grown in medium containing garlic for 0, 2, 4, 6, and 8 weeks. The total phenolic and total flavonoid contents of RYRG extracts were increasing with the length of culture periods. The DPPH free radical scavenging activity of RYRG extracts also increased with culture time. The RYRG extracts prevented brain lipid peroxidation in culture time dependent manner. The RYRG extracts showed anti-proliferative effects against HepG2 human liver cancer cells, HT-29 human colon cancer cells, and B16F10 murine melanoma cells. The IC50 value of 8-week fermented RYRG extract was the lowest among sample groups. Therefore, the results indicated that RYRG extracts exhibit culture time-dependent antioxidant and anti-cancer activities associated with the increase on phenolic and flavonoid contents. The RYRG extract is therefore a promising candidate as chemopreventive agents.