Four new monacolin analogs from Monascus purpureus-fermented rice

Structural Elucidation and Complete NMR Spectral Assignments of Monascus Monacolin Analogs

One new monacolin analog, monacolin V (1), together with two new monacolin-like natural products, 6-hydroxyl monacolin P (2) and 3-keto monacolin S (3), were isolated from the ethyl acetate portion of red yeast rice ethanol extract. Their structures were identified by HRESIMS and NMR experiments, and the complete assignments of 1H and 13C NMR data for three compounds were obtained by the aid of HSQC, HMBC, 1H-1H COSY, and NOESY data. This is the first time that the NMR data of compounds 2 and 3 have been fully assigned.

Red fermented rice elution fractions inhibits cancer cell proliferation by regulating the FGFR1/PI3K/AKT signaling pathway

This study aims to elucidate the potential targets and molecular mechanisms underlying the anticancer effects of Red fermented rice extract using molecular simulation techniques. The inhibitory effects of different elution fractions of Red fermented rice extract on A549 and MCF-7 cell proliferation were evaluated through CCK-8 assays. Liquid chromatography-mass spectrometry (LC-MS) was employed to elucidate the structural information of active components, while molecular simulation techniques aided in identifying target proteins based on small molecule structures. Protein immunoblotting was utilized to investigate the mechanisms of action of relevant targets. The study found that the petroleum ether-ethyl acetate and ethyl acetate elution fractions of Red fermented rice extract significantly inhibited A549 and MCF-7 cell proliferation, with stronger effects observed on A549 cells. LC-MS structural analysis identified 25 small molecule structures. Molecular simulations successfully revealed interaction between active elution fractions of Red fermented rice extract and the cancer-related protein FGFR1. Further investigation into the phosphorylation of FGFR1 and its downstream pathway targets PI3K/AKT demonstrated that the active elution fractions exerted their anticancer activity by inhibiting the phosphorylation of FGFR1, PI3K, and AKT proteins. This comprehensive study, integrating CCK-8 assays, LC-MS, molecular simulation techniques, and protein immunoblotting, provides a deep understanding of the anticancer mechanisms of Red fermented rice extract, guiding its further development and clinical application.

Structural elucidation and complete NMR spectral assignments of Monascus monacolin analogues

Three new monacolin analogues, 3,6-dihydroxy-monacolin P (1), 6-methoxy monacolin S (2), and 6-methoxy dehydromonacolin S (3), were isolated from a fraction that strongly inhibited 3-hydroxy-3-methylglutaryl-CoA reductase from the ethyl acetate portion of red yeast rice ethanol extract. Their structures were determined through a combination of 1D and 2D NMR experiments, mass spectrometry analysis, and known literature reports.

Investigations into Chemical Components from Monascus purpureus with Photoprotective and Anti-Melanogenic Activities

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.

Perspectives on Functional Red Mold Rice: Functional Ingredients, Production, and Application

Monacolin K (MK) is a secondary metabolite of the Monascus species that can inhibit cholesterol synthesis. Functional red mold rice (FRMR) is the fermentation product of Monascus spp., which is rich in MK. FRMR is usually employed to regulate serum cholesterol, especially for hypercholesterolemic patients who refuse statins or face statin intolerance. The present perspective summarized the bioactive components of FRMR and their functions. Subsequently, efficient strategies for FRMR production, future challenges of FRMR application, and possible directions were proposed. This perspective helps to understand the present situation and developmental prospects of FRMR.

Polyhydroxylated sterols from Monascus purpureus-fermented rice

Using a cell-based cytotoxicity assay, two new polyhydroxylated sterols, 16(S),22(S)-epoxy-3β,5α,6β,20(R),23(R),25-hexahydroxy-7-ergostene and 3β,7β,8α,25-tetrahydroxy-5,22E-ergostadiene were isolated from the ethyl acetate portion of the ethanolic extract of Monascus purpureus. Their structures were elucidated by spectroscopic analysis and in comparison with those reported in the literature. Both compounds showed cytotoxic activity against the lung adenocarcinoma (A549) with IC₅₀ values of 12.6 and 18.5 μM, exhibited moderate activities against human ovarian cancer (A2780), with IC₅₀ values of 8.8 and 9.4 μM.

Quality and Authenticity Control of Functional Red Yeast Rice-A Review

Red yeast rice (RYR) is made by fermenting the rice with Monascus. It is commonly used in food colorants, dyeing, and wine making in China and its neighboring countries. Nowadays RYR has two forms on the market: common RYR is used for food products, the other form is functional RYR for medicine. However, some researchers reported that commercial lovastatin (structure is consistent with monacolin K) is illegally added to common RYR to meet drug quality standards, so as to imitate functional RYR and sell the imitation at a higher price. Based on current detection methods, it is impossible to accurately distinguish whether functional RYR is adulterated. Therefore, it is especially important to find a way to authenticate functional RYR. In the current review, the advances in history, applications, components (especially monacolins, monacolins detection methods), quality standards, authentication methods and perspectives for the future study of RYR are systematically reviewed.