Red yeast rice dietary supplements have been proven to ameliorate hyperglycemia, but the mechanism was unclear. In this work, ankaflavin (AK) and monascin (MS), as typical pigments derived from red yeast rice, were found to exert noteworthy inhibitory ability against α-glucosidase, with an IC50 of 126.5 ± 2.5 and 302.6 ± 2.5 μM, respectively, compared with acarbose (IC50 = 341.3 ± 13.6 μM). They also exhibited mixed-type inhibition of α-glucosidase in vitro and caused fluorescence quenching through the static-quenching process. Molecular-docking studies indicated that AK and MS bind to amino acid residues outside the catalytic center, which induces structural changes in the enzyme, thus influencing its catalytic activity. The anti-glycation ability of Monascus-fermented products was evaluated, and they exhibited a high inhibition rate of 87.1% in fluorescent advanced glycation end-product formation at a concentration of 0.2 mg mL-1, while aminoguanidine showed a rate of 75.7% at the same concentration. These results will be significant in broadening the application scope of Monascus pigments, especially AK and MS, in treating type 2 diabetes.

Monascus purpureus copiously yields beneficial secondary metabolites , including Monascus pigments, which are broadly used as food additives, as a nitrite substitute in meat products, and as a colorant in the food industry. Monascus yellow pigments (monascin and ankaflavin) have shown potential antidiabetic, antibacterial, anti-inflammatory, antidepressant, antibiotic, anticancer, and antiobesity activities. Cosmetic and textile industries are other areas where it has established its potential as a dye. This paper reviews the production methods of Monascus yellow pigments, biosynthesis of Monascus pigments from M. purpureus, factors affecting yellow pigment production during fermentation, and the pharmacological properties of monascin and ankaflavin.

ANKASCIN 568-R is an extract derived from red mold rice (RMR) fermented using Monascus purpureus NTU 568. RMR fermented using M. purpureus NTU 568 prevents cardiovascular diseases and decreases blood lipid levels. This study evaluates the safety of ANKASCIN 568-R, since it has not determined yet. After daily oral ANKASCIN 568-R for 13 consecutive weeks, we evaluated the toxicity tolerance of Sprague-Dawley rats and performed dose formulation analysis on monascin and ankaflavin. The dose formulation analysis showed that ANKASCIN 568-R concentrations were lower than the target concentration and out of range ( ± 15%) at week 8 and on the last dosing day for both monascin (all dose groups) and ankaflavin at the 100 mg/kg dose. The lowest reported concentrations for the low, middle, and high dose formulations were 34.7, 115.2, and 398.1 mg/mL, respectively. We also evaluated the genotoxicity of ANKASCIN 568-R and showed no genotoxicity potential at all ANKASCIN 568-R doses investigated. The no observed adverse effect level of ANKASCIN 568-R was determined to be 796.2 mg/kg/day. This study revealed the first toxicity evaluation data of ANKASICN 568-R, and the data demonstrated ANKASICN 568-R was safe and can be used in daily life.

Alcohol metabolism causes an excessive accumulation of liver lipids and inflammation, resulting in liver damage. The yellow pigments monascin (MS) and ankaflavin (AK) of Monascus purpureus-fermented rice were proven to regulate ethanol-induced damage in HepG2 cells, but the complete anti-inflammatory and anti-fatty liver mechanisms in the animal model are still unclear. This study explored the roles of MS and AK in improving alcoholic liver injury. MS and AK were simultaneously fed to evaluate their effects and mechanisms in C57BL/6J mice fed the Lieber-DeCarli liquid alcohol diet for 6 weeks. The results indicated that MS and AK significantly reduced the serum aspartate aminotransferase and alanine aminotransferase activity, as well as the total liver cholesterol and triglyceride levels. The histopathological results indicated that MS and AK prevented lipid accumulation in the liver. MS and AK effectively enhanced the activity of antioxidant enzymes and reduced the degree of lipid peroxidation; AK was particularly effective and exhibited a superior preventive effect against alcoholic liver injury and fatty liver. In addition to inhibiting the phosphorylation of the MAPK family, MS and AK directly reduced TNF-α, IL-6, and IL-1β levels, thereby reducing NF-κB and its downstream iNOS and COX-2 expressions, as well as increasing PPAR-γ, Nrf-2, and HO-1 expressions to prevent liver damage. MS and AK also directly reduced TNF-α, IL-6, and IL-1β expression, thereby reducing the production of NF-κB and its downstream iNOS and COX-2, and increasing PPAR-γ, Nrf-2, and HO-1 expressions, preventing alcohol damage to the liver.

Monascus yellow pigments (MYPs), as food colorants, are of great interest to the food industry, because of their beneficial biological activities. In this study, a comparative metabolomics strategy revealed the metabolic regulatory mechanism of MYP overproduction, comparing ammonium chloride with peptone as nitrogen sources. Metabolomics-based multivariate regression modeling showed that metabolic biomarkers/modules, such as glucose, lactate, and the pentose phosphate (PP) pathway, were closely associated with the biosynthesis of MYPs. Exogenous addition of glucose increased production of MYPs, whereas lactate reduced it. Inhibition of the PP pathway with dehydroepiandrosterone decreased MYP production, while increasing the shunting production of orange and red pigments. All these treatments significantly changed the expression profiles of the pigment biosynthetic gene cluster and the mycelial morphology. Overall, this study demonstrates the feasibility of elucidating the mechanism of MYP biosynthesis by comprehensive metabolomics analysis, as well as discovering potential engineering targets of efficiency improvements to commercial MYP production. KEY POINTS: • Comparative metabolomics revealed the biomarkers/modules of MYP production. • A rational exogenously adding strategy was implemented to regulate MYP synthesis. • Expression profiles of gene cluster and mycelial morphology were characterized.

The pigment was extracted from Penicillium aculeatum, purified and characterized as Ankaflavin by spectroscopic analysis. The stability of the pigment was determined under various conditions and was found to possess high stability. The cytotoxicity property of the purified pigment was determined by MTT assay in MCF-7, HCT116 and PC-3 and the studies were compared with its activity in CHOK1 cells. In MCF-7 and in CHOK 1 cells, the pigment exhibited very less toxicity. However, significant cytotoxicity was observed in HCT116 and PC-3 cells with IC50 of 162 μg mL-1 and 85 μg mL-1 for HCT116 and PC-3 cells respectively. In vitro toxicity was tested by haemolysis assay and MTT assay in HEK 293 cells. The pigment showed least cytotoxicity (<5%) at 160 and 320 μg mL-1 concentrations HEK 293 cells and negligible (<5%) toxicity on human erythrocytes at 160 and 320 μg mL-1, the highest concentrations tested.

Monascus species produce several potent bioactive metabolites through polyketide secondary metabolic pathways; however, little is known of the regulation of metabolic processes in this organism. Therefore, we investigated the effect of extreme growth conditions on the production of secondary metabolites by Monascus purpureus strain NTU 568 and identified pathways that plausibly regulate the polyketide pathways by using proteomic analysis. Citrinin, a type of antibiotic, is synthesized through the polyketide pathway in M. purpureus NTU 568. We hypothesized that production of citrinin might be inhibited by ethanol. When M. purpureus NTU 568 was cultured in the medium containing 4% ethanol, the secretion of secondary metabolites was inhibited, but the dry cell weight was increased. We also found that branched chain amino acid degradation and the expression level of aldehyde dehydrogenase (ALDH) were downregulated, but proteins related to the heat shock response were induced. Furthermore, polyketide synthesis-related proteins, fatty acid synthase, epoxide hydrolase, and proteins involved in the shikimate secondary metabolic pathway were inhibited by ethanol treatment. These results suggested that reduced production of polyketide metabolites resulted not only from the expression levels of proteins in the polyketide synthesis pathway but also from reduction in the concentration of primary metabolism-generated molecules (e.g., acetyl-CoA, fatty acids) that are used as substrates for polyketide syntheses. This study provides insights into the polyketide secondary metabolism of Monascus as well as into improvement of the production of bioactive secondary metabolites in Monascus species.

Hyperlipidemia and inflammation play important roles in the development and progression of atherosclerosis. Atherosclerosis is regarded as an inflammatory response of blood vessels to injury at the start of atherosclerotic plaque formation, which then leads to cardiovascular events. Edible fungi of the Monascus species have been used as traditional Chinese medicines in East Asia for several centuries. The fermented products of Monascus purpureus NTU 568 possess a number of functional secondary metabolites including the anti-inflammatory pigments monascin and ankaflavin. Compounds derived from M. purpureus have been shown to have hypolipidemic effects. We aimed to evaluate the effects of M. purpureus NTU 568 fermentation product an extract (Ankascin 568 plus) containing monascin and ankaflavin on blood lipids in volunteers with borderline high levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) by conducting a 12-week randomized, double-blind, placebo-controlled, adaptive-design study. This study enrolled 40 subjects aged 18-65 years from a population of patients with TC and LDL-C levels of ≥180 mg/dL and 130-190 mg/dL, respectively. Measured endpoints included lipid profile, liver, kidney and thyroid function, electrolyte balance, creatinine phosphokinase, and fasting blood glucose. After 4 weeks of treatment (500 mg Ankascin 568 plus/day), the changes in the lipid levels showed that the active products had a more favorable effect than the placebo. Compared to the baseline, statistically significant decreases of 11.9% and 19.0% were observed in TC and LDL-C levels, respectively (p < 0.05 for all pairs). This study demonstrated that subjects administered one 500 mg capsule of Ankascin 568 plus for more than 4 weeks exhibited a significant reduction in serum TC and LDL-C levels. Therefore, Ankascin 568 plus may be a potentially useful agent for the regulation of blood lipids and the treatment of coronary artery diseases.

BACKGROUND: Alcoholic hepatitis is a necroinflammatory process that is associated with fibrosis and leads to cirrhosis in 40% of cases. The hepatoprotective effects of red mold dioscorea (RMD) from Monascus purpureus NTU 568 were evaluated in vivo using a mouse model of chronic alcohol-induced liver disease (ALD).
RESULTS: ALD mice were orally administered vehicle (ALD group) or vehicle plus 307.5, 615.0 or 1537.5 mg kg-1 (1 ×, 2 × and 5 ×) RMD for 5 weeks. RMD lowered serum leptin, hepatic total cholesterol, free fatty acid and hepatic triglyceride levels and increased serum adiponectin, hepatic alcohol dehydrogenase and antioxidant enzyme levels. Furthermore, ankaflavin (AK) and monascin (MS), metabolites of RMD fermented with M. purpureus 568, induced peroxisome proliferator-activated receptor-γ expression and the concomitant suppression of ethanol-induced elevation of sterol regulatory element-binding transcription factor-1 and TG in HepG2 cells.
CONCLUSIONS: These results indicate the hepatoprotective effect of Monascus-fermented RMD. Moreover, AK and MS were identified as the active constituents of RMD for the first time and were shown to protect against ethanol-induced liver damage. © 2017 Society of Chemical Industry.

Hypertension and cardiovascular complications are the leading causes of death worldwide. Antihypertensive drugs often cause various side effects, and improper use of antihypertensive medications can result in irreparable damage. Edible fungi of the Monascus species have been used as traditional Chinese medicines in Southeast Asia for several centuries. The fermented products of Monascus purpureus NTU 568 (ANKASCIN 568) possess a number of functional secondary metabolites including the anti-inflammatory pigments monascin (MS) and ankaflavin (AK). In this study, a double-blind, placebo-controlled clinical trial was performed in which patients with mild to moderate hypertension were randomly assigned to receive placebo or two 500-mg capsules of Ankascin 568 for 8 weeks. The effects of this treatment on the regulation of blood pressure (BP) were then examined. The results showed that systolic blood pressure (SBP) decreased from 141.6 ± 12.0 to 133.9 ± 14.4 mmHg (P < 0.05), and diastolic blood pressure (DBP) decreased from 91.7 ± 8.1 to 84.8 ± 7.4 mmHg (P < 0.05). Moreover, Ankascin 568 treatment effectively reduced serum triglycerides and total cholesterol (TC), increased high-density lipoprotein cholesterol (HDL-C), and reduced low-density lipoprotein cholesterol (LDL-C) levels, thereby improving the serum lipid profile. Additionally, administration of Ankascin 568 did not cause significant rhabdomyolysis nor impaired the metabolic or physiological functions of the liver or kidney. In conclusion, patients administered Ankascin 568 for 8 weeks exhibited significant in reduction of SBP, serum TC and LDL-C levels, which should contribute to better cardiovascular health.