Uric acid (UA) is an end product of purine metabolism by the enzyme xanthine oxidase (XOD). Hyperuricemia is characterized by the accumulation of serum UA and is an important risk factor for gout and many chronic disorders. XOD inhibitors or uricase (catalyzes UA to the more soluble end product) can prevent these chronic diseases. However, currently available hypouricemic agents induce severe side effects. Therefore, we developed new microbial fermented extracts (MFEs) with substantial XOD inhibition activity from Lactobacillus (MFE-21) and Acetobacter (MFE-25), and MFE-120 with high uricase activity from Aspergillus. The urate-lowering effects and safety of these MFEs were evaluated. Our results showed that MFE-25 exerts superior urate-lowering effects in the therapeutic model. In the preventive model, both MFE-120 and MFE-25 significantly reduced UA. The results of the safety study showed that no organ toxicity and no treatment-related adverse effects were observed in mice treated with high doses of MFEs. Taken together, the results showed the effectiveness of MFEs in reducing hyperuricemia without systemic toxicity in mice at high doses, suggesting that they are safe for use in the treatment and prevention of hyperuricemia.

Monascus species are asexually or sexually reproduced homothallic fungi that can produce a red colorant, specifically the so-called red yeast rice or Anka, which is used as a food ingredient in Asia. Traditional experiences of using Monascus for treating indigestion, enhancing blood circulation, and health remedies motivate us to investigate and repurpose Monascus-fermented products. Here, two new 5H-cyclopenta[c]pyridine type azaphilones, 5S,6S-monaspurpyridine A (1) and 5R,6R-monaspurpyridine A (2), two new xanthonoids, monasxanthones A and B (3 and 4), one new naphthalenone, monasnaphthalenone (5), and one new azaphilone, monapurpurin (6), along with two known compounds were isolated from the 70% EtOH extract of a citrinin-free domesticated strain M. purpureus BCRC 38110. The phytochemical properties of the xanthonoid and naphthalenone components were first identified from Monascus sp. differently from the representative ingredients of polyketide-derived azaphilones. UVB-induced cell viability loss and reactive oxygen species (ROS) overproduction in human keratinocytes were attenuated by monascuspirolide B (7) and ergosterol peroxide (8), indicating their photoprotective potentials. Ergosterol peroxide (8) decreased the melanin contents and tyrosinase activities of mouse melanocytes, depending on the concentration, suggesting their anti-melanogenic effects. In conclusion, six new and two known compounds were isolated from M. purpureus BCRC 38110, and two of them exhibited dermal protective activities. The results revealed the novel potential of M. purpureus for developing natural cosmeceutics against skin photoaging.

Four new pyridine derivatives, monasnicotinates A–D (1–4) were isolated from the red yeast rice of Monascus pilosus BCRC 38093. Their structures were elucidated on the basis of physicochemical evidence, in-depth NMR spectroscopic analysis, and high-resolution mass spectrometry. Their inhibitory effects on NO production was also evaluated.