Investigation of the 95% EtOH extract of red yeast rice fermented with the pink mutant of the fungus Monascus purpureus BCRC 38108 led to the isolation of three new azaphilone derivatives, namely monascusazaphilones A–C (1–3), together with two known compounds. Compounds 1–3 were isolated from this species for the first time. Their structures were elucidated by 1-D and 2-D nuclear magnetic resonance spectroscopy together with HR–ESI–MS analysis and comparison of the spectroscopic data with those reported in the literatures. All isolates were evaluated for their inhibitory effects on nitric oxide (NO) production by macrophages. Among the isolates, compound 1 demonstrated stronger inhibition on NO production.

Three new and rare chromone derivatives, epiremisporine C (1), epiremisporine D (2), and epiremisporine E (3), were isolated from marine-derived Penicillium citrinum, together with four known compounds, epiremisporine B (4), penicitrinone A (5), 8-hydroxy-1-methoxycarbonyl-6-methylxanthone (6), and isoconiochaetone C (7). Among the isolated compounds, compounds 2–5 significantly decreased fMLP-induced superoxide anion generation by human neutrophils, with IC₅₀ values of 6.39 ± 0.40, 8.28 ± 0.29, 3.62 ± 0.61, and 2.67 ± 0.10 μM, respectively. Compounds 3 and 4 exhibited cytotoxic activities with IC₅₀ values of 43.82 ± 6.33 and 32.29 ± 4.83 μM, respectively, against non-small lung cancer cell (A549), and Western blot assay confirmed that compounds 3 and 4 markedly induced apoptosis of A549 cells, through Bcl-2, Bax, and caspase 3 signaling cascades.

Phytochemical investigation of the EtOAc-soluble fraction of the ethanolic extract of a yellow mutant of the fungus Monascus purpureus BCRC 38110 (Eurotiaceae) grown on rice resulted in the isolation of one new azaphilone derivative, monapurpureusone (1), one acetophenone metabolite isolated for the first time from natural source, monapurpureusin (2), along with four known compounds, TW94a (3), ergosterol (4), monascin (5), and ankaflavin (6). The structures and relative configurations of these compounds were elucidated by spectroscopic analyses, including 1D- and 2D-NMR spectroscopy and mass spectrometry, and by the comparison of their NMR data with those of related compounds. Some phytochemicals were evaluated for both anti-inflammatory activity through the measurement of nitric oxide (NO) production levels in lipopolysaccharide (LPS)-stimulated murine-derived macrophages RAW264.7 cell lines and antioxidant activities. Graphical Abstract

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.