Anti-inflammatory properties of yellow and orange pigments from Monascus purpureus NTU 568.

The Monascus species has been used in foods for thousands of years in China. In this study, 10 azaphilone pigments, including four yellow and six orange pigments, were isolated from the fermented rice and dioscorea of Monascus purpureus NTU 568. By employing lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells, we determined the inhibitory activities of these pigments on nitric oxide (NO) production. As a result, four orange pigments, monaphilols A-D, showed the highest activities (IC50 = 1.0-3.8 μM), compared with the other two orange pigments, monascorubrin (IC50 > 40 μM) and rubropunctatin (IC50 = 21.2 μM), and the four yellow pigments ankaflavin (IC50 = 21.8 μM), monascin (IC50 = 29.1 μM), monaphilone A (IC50 = 19.3 μM), and monaphilone B (IC50 = 22.6 μM). Using Western blot and ELISA kits, we found that treatments with 30 μM of the yellow pigments and 5 μM of the orange pigments could down-regulate the protein expression of inducible nitric oxide synthase (iNOS) and suppress the production of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6). We also used two animal experiments to evaluate the anti-inflammatory effects of these pigments. In a 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema model, eight of these pigments (0.5 mg/ear) could prevent ear edema against TPA administrations on the ears of BALB/c mice. In an LPS-injection mice model, several of these pigments (10 mg/kg) could inhibit the NO, TNF-α, IL-1β, and IL-6 levels in the plasma of BALB/c mice. As concluded from the in vitro and in vivo studies, six azaphilonoid pigments, namely, ankaflavin, monaphilone A, and monaphilols A-D, showed high potential to be developed into chemopreventive foods or drugs against inflammation-associated diseases.