Monascus yellow, red and orange pigments from red yeast rice ameliorate lipid metabolic disorders and gut microbiota dysbiosis in Wistar rats fed on a high-fat diet

Molecular Mechanism of Mok I Gene Overexpression in Enhancing Monacolin K Production in Monascus pilosus

Monascus species are capable of producing various active metabolites, including monacolin K (MK) and pigments. Studies have shown that the overexpression of the mok I gene from the MK synthesis gene cluster in Monascus species can significantly increase MK production; however, the molecular mechanism has not yet been fully elucidated. Therefore, this study focused on the mok I gene of Monascus pilosus to construct overexpression strains of the mok I gene, resulting in high-yield MK production. Sixteen positive transformants were obtained, seven of which produced 9.63% to 41.39% more MK than the original strain, with no citrinin detected in any of the transformants. The qRT-PCR results revealed that the expression levels of mok I in the transformed strains TI-13, TI-24, and TI-25 increased by more than 50% compared to the original strain at various fermentation times, with the highest increase being 10.9-fold. Furthermore, multi-omics techniques were used to analyze the molecular mechanisms underlying enhanced MK production in transformed strains. The results indicated that mok I overexpression may enhance MK synthesis in M. pilosus by regulating the expression of key genes (such as MAO, HPD, ACX, and PLC) and the synthesis levels of key metabolites (such as delta-tocopherol and alpha-linolenic acid) in pathways linked to the biosynthesis of cofactors, the biosynthesis of unsaturated fatty acids, tyrosine metabolism, ubiquinone and other terpenoid-quinone biosynthesis, alpha-linolenic acid metabolism, and glycerophospholipid metabolism. These findings provide a theoretical basis for further study of the metabolic regulation of MK in Monascus species and for effectively enhancing their MK production.

Monascus pigments suppress fructose-mediated BSA glycation by trapping methylglyoxal and covalent binding to proteins

In this study, four Monascus pigments (ankaflavin, AK; monascin MS; rubropunctatin, O1; monascorubrin, O2) were proved to exhibit considerable anti-glycation properties in bovine serum albumin (BSA)-fructose model. AK (40.62 %) and MS (48.38 %) were found to exert lower inhibitory effects on the formation of fluorescent advanced glycation end products (AGEs) than aminoguanidine (59.4 %), while O1 (90.64 %) and O2 (93.82 %) displayed much stronger abilities. AK and MS could trap methylglyoxal (MGO) with maximum capture rates of 85.67 % and 84.90 %, respectively, and only mono-MGO adducts of them were detected. LC-Orbitrap MS/MS analysis revealed that four pigments significantly altered the type and reduced the number of the glycated sites and they all covalently bound to BSA, with O1 and O2 possessing high reactivity. Altogether, AK and MS suppressed fluorescent AGEs formation mainly via trapping MGO and covalently interacting with BSA, and blocking free amino groups was the dominant mechanism for O1 and O2. These findings presented new insights into Monascus pigments as dietary supplement for inhibiting protein glycation.

Specific gut microbiome's role in skin pigmentation: insights from SCARB1 mutants in Oujiang colour common carp

AIMS

Beyond the pivotal roles of the gut microbiome in initiating physiological processes and modulating genetic factors, a query persists: Can a single gene mutation alter the abundance of the gut microbiome community? Not only this, but the intricate impact of gut microbiome composition on skin pigmentation has been largely unexplored.

METHODS AND RESULTS

Based on these premises, our study examines the abundance of lipase-producing gut microbes about differential gene expression associated with bile acid synthesis and lipid metabolism-related blood metabolites in red (whole wild) and white (whole white wild and SCARB1-/- mutant) Oujiang colour common carp. Following the disruption of the SCARB1 gene in the resulting mutant fish with white body colour (SCARB1-/-), there is a notable decrease in the abundance of gut microbiomes (Bacillus, Staphylococcus, Pseudomonas, and Serratia) associated with lipase production. This reduction parallels the downregulation seen in wild-type white body colour fish (WW), as contrasting to the wild-type red body colour fish (WR). Meanwhile, in SCARB1-/- fish, there was a downregulation noted not only at the genetic and metabolic levels but also a decrease in lipase-producing bacteria. This consistency with WW contrasts significantly with WR. Similarly, genes involved in the bile acid synthesis pathway, along with blood metabolites related to lipid metabolism, exhibited downregulation in SCARB1-/- fish.

CONCLUSIONS

The SCARB1 knockout gene blockage led to significant alterations in the gut microbiome, potentially influencing the observed reduction in carotenoid-associated skin pigmentation. Our study emphasizes that skin pigmentation is not only impacted by genetic factors but also by the gut microbiome. Meanwhile, the gut microbiome's adaptability can be rapidly shaped and may be driven by specific single-gene variations.

Monascus red pigments alleviate high-fat and high-sugar diet-induced NAFLD in mice by modulating the gut microbiota and metabolites

Monascus red pigments (MRP) may have benefits against NAFLD with an unclear mechanism. This study aimed to explore the protective effect of MRP supplementation against NAFLD through regulation of gut microbiota and metabolites. The C57BL/6 mice animals were randomly allocated into the normal diet (NC), HFHS diet-induced NAFLD model, and MRP intervention group fed with HFHS diet. Serum lipid profiles and liver function parameters were measured. Liver and colon histopathology analysis was conducted to determine the injury in the liver and colon. 16S rRNA gene sequencing was employed to analyze gut microbial composition from fecal samples. Untargeted metabonomics was performed to analyze changes in metabolites in serum and fecal samples. MRP supplementation significantly improved the HFHS-induced alterations in body weight, lipid profiles, and liver function (p < .01). MRP supplementation decreased the abundance of Akkermansia, Candidatus saccharimonas, Dubosiella, and Oscillibacter, while increasing Lactobacillus, Lachnospiraceae NK4A136 group, and Rikenella in mice fed the HFHS diet. Furthermore, MRP supplementation improved the serum and fecal metabolic profiles induced by the HFHS diet, primarily involving the arachidonic acid metabolism, unsaturated fatty acid biosynthesis, and adipocyte lipolysis pathways. Liver function and lipid profiles were closely associated with the abundance of Lactobacillus, Streptococcus, Oscillibacter, Akkemansia, and Desulfovibrio (p < .01). These findings revealed that MRP supplementation may help restore gut microbiota composition and balance its metabolites, thereby improving NAFLD. This study presents a novel outlook on the potential benefits of MRP supplementation in ameliorating NAFLD and supports the application of MRP as a new functional food.

Phycobiliprotein Peptide Extracts from Arthrospira platensis Ameliorate Nonalcoholic Fatty Liver Disease by Modulating Hepatic Lipid Profile and Strengthening Fat Mobilization

Arthrospira platensis phycobiliprotein peptide extracts (PPEs) exhibit potential mitigative effects on hepatic steatosis. However, the precise role of PPEs in addressing high-fat-induced nonalcoholic fatty liver disease (NAFLD), as well as the underlying mechanism, remains to be elucidated. In this study, NAFLD was induced in rats through a high-fat diet (HFD), and the rats were subsequently treated with PPEs for a duration of 10 weeks. The outcomes of this investigation demonstrate that PPE supplementation leads to a reduction in body weight gain, a decrease in the accumulation of lipid droplets within the liver tissues, alterations in hepatic lipid profile, regulation of lipolysis-related gene expression within white adipose tissues and modulation of intestinal metabolites. Notably, PPE supplementation exhibits a potential to alleviate liver damage by manipulating neutral lipid metabolism and phospholipid metabolism. Additionally, PPEs appear to enhance fat mobilization by up-regulating the gene expression levels of key factors such as HSL, TGL, UCP1 and UCP2. Furthermore, PPEs impact intestinal metabolites by reducing the levels of long-chain fatty acids while concurrently increasing the levels of short-chain fatty acids. The findings from this study unveil the potential of PPE intervention in ameliorating NAFLD through the modulation of hepatic lipid profile and the reinforcement of the fat mobilization of intestinal metabolites. Thus, PPEs exhibit noteworthy therapeutic effects in the context of NAFLD.

LipoCol Forte capsules reduce the risk of liver cancer: A propensity score-matched, nationwide, population-based cohort study

BACKGROUND

Liver cancer is among the top five most common cancers globally. Lipid-lowering drugs such as statins can lower the risk of liver cancer, but may also cause liver damage. LipoCol Forte capsules (LFC), a red yeast rice product, have demonstrated significant antihypercholesterolemic effects and a good safety profile in clinical studies.

AIM

To evaluate whether LFC lowers the risk of liver cancer in adults in this propensity score-matched, nationwide, population-based cohort study.

METHODS

We used data from Taiwan’s National Health Insurance Research Database, which includes electronic medical records for up to 99.99% of Taiwan’s population. LFC users and LFC non-users were matched 1:1 by propensity scores between January 2010 and December 2017. All had follow-up data for at least 1 year. Statistical analyses compared demographic distributions including sex, age, comorbidities, and prescribed medications. Cox regression analyses estimated adjusted hazard ratios (aHRs) after adjusting for potential confounders.

RESULTS

We enrolled 33231 LFC users and 33231 non-LFC users (controls). No significant differences between the study cohorts were identified regarding comorbidities and medications [standardized mean difference (SMD) < 0.05]. At follow-up, the overall incidence of liver cancer was significantly lower in the LFC cohort compared with controls [aHR 0.91; 95% confidence interval (CI): 0.86-0.95; P < 0.001]. The risk of liver cancer was significantly reduced in both females (aHR 0.87; 95%CI: 0.8-0.94; P < 0.001) and males (aHR 0.93; 95%CI: 0.87-0.98; P < 0.01) in the LFC cohort compared with their counterparts in the non-LFC cohort. The antitumor protective effects applied to patients with comorbidities (including hypertension, ischemic stroke, diabetes mellitus, hyperlipidemia, hepatitis B infection and hepatitis C infection). Those using LFC for more than 84 drug days had a 0.64-fold lower risk of liver cancer compared with controls (P < 0.001). Compared with controls, the risk of developing liver cancer in the LFC cohort progressively decreased over time; the lowest incidence of liver cancer occurred in LFC users followed-up for more than 6 years (27.44 vs 31.49 per 1,000 person-years; aHR 0.75; 95%CI: 0.68-0.82; P < 0.001).

CONCLUSION

This retrospective cohort study indicates that LFC has a significantly protective effect on lowering the risk of liver cancer, in a dose-dependent and time-dependent manner.

Genetic responses to adding nitrates to improve hydrophilic yellow pigment in Monascus fermentation

Nitrates can stimulate the biosynthesis of hydrophilic yellow pigments (HYPs) in Monascus ruber CGMCC 10910. To explore the molecular mechanisms whereby nitrates (NaNO₃ and NH₄NO₃) regulate HYP production, an integrated transcriptomic and proteomic analysis was conducted in this study. Nitrate addition led to an approximately 75% higher HYP production compared with the untreated group, especially compounds Y3 and Y4. Comparative transcriptomic analysis found that mpigsA, H, K, L, and P genes involved in yellow pigment biosynthesis were significantly upregulated. In addition, pigment biosynthesis-related (carbon catabolism, amino acid metabolism, polyketide synthesis, and fatty acid metabolism) genes were upregulated to provide precursors and energy for HYP biosynthesis and cell growth. Secretion-related (cytomembrane ergosterol biosynthetic, and transport) pathways were also noticeably regulated to accelerate transmembrane transport of HYPs. Meanwhile, proteomic analysis showed that nitrates improved the protein expression of hybrid polyketide synthase-nonribosomal peptide synthetase, oxidoreductase, glucoamylase, endo-1,4-beta-xylanase, O-acetylhomoserine, and isocitrate lyase to enhance HYP production. These findings demonstrated the regulatory mechanism of nitrates for enhancing HYP production in Monascus. KEY POINTS: • Nitrates stimulated the biosynthesis of Monascus hydrophilic yellow pigments (HYPs) • Nitrates affected transcriptional level of pigment biosynthesis- and transport genes • Increased expression of hybrid PKS-NRPS and transporters promoted production of HYPs.

Synergistic effect of polysaccharides and flavonoids on lipid and gut microbiota in hyperlipidemic rats

Hyperlipidemia is a global health risk factor, and its development is closely related to the absorption and metabolism of lipids in the intestine. In this study, the Auricularia auricula polysaccharide, the Tremella polysaccharide, and hawthorn flavonoids were mixed by equal weight (HDC), and then its effect on the intervention in the intestine and blood lipids of hyperlipidemic rats on a high-fat diet (HFD) was investigated. The results revealed that HDC significantly inhibited the development of hyperlipidemia and reduced lipid levels and fat accumulation. In addition, HDC improved the edema deformation of intestinal epithelial cells, impaired the intestinal barrier induced by HFD, and improved the antioxidant capacity of the intestine. HDC showed a significant synergistic effect. Analysis of the gut microbiota by 16s rRNA gene sequencing showed that HDC reduced the ratio of Bacteroidetes/Firmicutes and the relative abundance of actinomycetes. At the genus level, the relative abundance of Lactobacillus, Rumincococcaceae-UCG-14, and Muribaculaceae was increased and the relative abundance of Allobaculum, Corynebacterium-1, Blautia, and Turicibucter was decreased. Intestinal lipidomics showed that HDC reduced the levels of DGDG, LPE, PG, phSM, PIP2, SoG1, and SM in the intestine of HFD rats, although there were no significant differences in LPE, PG, and phSM. 42 HDC-acting lipid biomarkers were screened. In conclusion, these findings support the potential of HDC intervention to prevent hyperlipidemia by regulating gut microbiota and lipid absorption and metabolism in the intestine.

Natural Foods for the Treatment of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. The etiology of NAFLD is highly heterogeneous, which occurs and develops under the joint action of metabolism, inflammation, genetics, environment, and gut microbiota. At present, the principal therapeutic modalities targeting NAFLD are lifestyle interventions such as weight loss through diet and exercise. At present, there is no established therapy for the treatment of NAFLD, and many therapies are associated with a variety of side effects. A great number of in vitro and in vivo experiments have indicated that there are many natural foods that have therapeutic potential for NAFLD. This review summarizes the natural foods and their mechanisms that were found in recent years, furthermore, provides further information relevant to the treatment of NAFLD.

Modulation of gut microbiota and lipid metabolism in rats fed high-fat diets by Ganoderma lucidum triterpenoids

Ganoderma lucidum triterpenoids (GP) have been reported to help prevent and improve hyperlipidemia. Modulation of the gut microbiota was proposed as underlying factor as well as a novel measure to prevent and treat hyperlipidemia. The effects of GP on high-fat diet (HFD)-induced hyperlipidemia and gut microbiota modulation were determined in rats. Ultra-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF MS-MS) indicated that GP were enriched with ganoderic acids G, B, H, A, and F. After feeding with GP supplementation, serum lipid levels including total triglyceride, total cholesterol, and low-density-lipoprotein cholesterol were significantly decreased in hyperlipidemic rats. Furthermore, administration of GP also has reversed the HFD-induced gut microbiota dysbiosis, including a significant increase in Alloprevotella and reduced proportion of Blautia. The result above suggests that GP would be developed as a functional food to ameliorate lipid metabolic disorders and hyperlipidemia.

Nutraceutical Approaches to Dyslipidaemia: The Main Formulative Issues Preventing Efficacy

Currently, the nutraceutical approach to treat dyslipidaemia is increasing in use, and in many cases is used by physicians as the first choice in the treatment of patients with borderline values. Nutraceuticals represent an excellent opportunity to treat the preliminary conditions not yet showing the pathological signs of dyslipidaemia. Their general safety, the patient's confidence, the convincing proof of efficacy and the reasonable costs prompted the market of new preparations. Despite this premise, many nutraceutical products are poorly formulated and do not meet the minimum requirements to ensure efficacy in normalizing blood lipid profiles, promoting cardiovascular protection, and normalizing disorders of glycemic metabolism. In this context, bioaccessibility and bioavailability of the active compounds is a crucial issue. Little attention is paid to the proper formulations needed to improve the overall bioavailability of the active molecules. According to these data, many products prove to be insufficient to ensure full enteric absorption. The present review analysed the literature in the field of nutraceuticals for the treatment of dyslipidemia, focusing on resveratrol, red yeast rice, berberine, and plant sterols, which are among the nutraceuticals with the greatest formulation problems, highlighting bioavailability and the most suitable formulations.

Dietary supplementation with Tolypocladium sinense mycelium prevents dyslipidemia inflammation in high fat diet mice by modulation of gut microbiota in mice

Obesity is a risk factor for many serious health problems, associated with inflammation, hyperlipidemia, and gut dysbiosis. Prevention of obesity is especially important for human health. Tolypocladium sinense is one of the fungi isolated from Chinese caterpillar fungus, which is a traditional Chinese medicine with putative gut microbiota modulation effects. Here, we established a high-fat diet (HFD)-induced hyperlipidemia mice model, which was supplemented with lyophilized T. sinense mycelium (TSP) daily to evaluate its anti-obesity effects. The results indicated that TSP supplementation can effectively alleviate the inflammatory response and oxidative stress levels caused by obesity. TSP significantly prevented obesity and suppressed dyslipidemia by regulating the expression of lipid metabolism genes in the liver. TSP is also effective in preventing the HFD-induced decline in short-chain fatty acid (SCFA) content. Gut microbiota profiling showed that TSP supplementation reversed HFD diet-induced bacterial abundance and also altered the metabolic pathways of functional microorganisms, as revealed by KEGG analysis. It is noteworthy that, correlation analysis reveals the up-regulated gut microbiota (Lactobacillus and Prevotella_9) are closely correlated with lipid metabolism parameters, gene expression of liver lipid metabolism and inflammatory. Additionally, the role of TSP in the regulation of lipid metabolism was reconfirmed by fecal microbiota transplantation. To sum up, our results provide the evidence that TSP may be used as prebiotic agents to prevent obesity by altering the gut microbiota, alleviating the inflammatory response and regulating gene expression of liver lipid metabolism.

Comparative Transcriptomic and Metabolomic Analyses Reveal the Regulatory Effect and Mechanism of Tea Extracts on the Biosynthesis of Monascus Pigments

Monascus pigments (MPs) are natural edible pigments with high safety and strong function, which have been widely used in food and health products. In this study, different types of tea extracts (rich in polyphenols) were used to regulate the biosynthesis of MPs. The results showed that 15% ethanol extract of pu-erh tea (T11) could significantly increase MPs production in liquid fermentation of Monaco's purpureus M3. Comparative transcriptomic and metabolomic analyses combined with reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to further explore the regulatory mechanism of T11 on the biosynthesis of MPs. Comparative transcriptomic analysis showed that there were 1503 differentially expressed genes (DEGs) between the Con group and the T11 group, which were mainly distributed in carbohydrate metabolism, amino acid metabolism, energy metabolism, lipid metabolism, metabolism of terpenoids and polyketides, etc. A total of 115 differential metabolites (DMs) identified by metabolomics between the Con and T11 groups were mainly enriched in glutathione metabolism, starch and sucrose metabolism, alanine, aspartic acid and glutamate metabolism and glycine, serine and threonine metabolism, etc. The results of metabolomics were basically consistent with those of gene transcriptomics, indicating that the regulatory effect of T11 on the biosynthesis of MPs is mainly achieved through affecting the primary metabolic pathway, providing sufficient energy and more biosynthetic precursors for secondary metabolism. In this study, tea extracts with low economic value and easy access were used as promoters of MPs biosynthesis, which may be conducive to the application of MPs in large-scale industrial production. At the same time, a more systematic understanding of the molecular regulatory mechanism of Monascus metabolism was obtained through multi-omics analysis.

Biogenic Synthesis of Silver Nanoparticles Using Catharanthus roseus and Its Cytotoxicity Effect on Vero Cell Lines

Background: Type 2 diabetes mellitus (DM2) is a chronic and sometimes fatal condition which affects people all over the world. Nanotherapeutics have shown tremendous potential to combat chronic diseases—including DM2—as they enhance the overall impact of drugs on biological systems. Greenly synthesized silver nanoparticles (AgNPs) from Catharanthus roseus methanolic extract (C. AgNPs) were examined primarily for their cytotoxic and antidiabetic effects. Methods: Characterization of C. AgNPs was performed by UV−vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and atomic force microscopy (AFM). The C. AgNPs were trialed on Vero cell line and afterwards on an animal model (rats). Results: The C. AgNPs showed standard structural and functional characterization as revealed by FTIR and XRD analyses. The zetapotential analysis indicated stability while EDX analysis confirmed the formation of composite capping with Ag metal. The cytotoxic effect (IC50) of C. AgNPs on Vero cell lines was found to be 568 g/mL. The animal model analyses further revealed a significant difference in water intake, food intake, body weight, urine volume, and urine sugar of tested rats after treatment with aqueous extract of C. AgNPs. Moreover, five groups of rats including control and diabetic groups (NC1, PC2, DG1, DG2, and DG3) were investigated for their blood glucose and glycemic control analysis. Conclusions: The C. AgNPs exhibited positive potential on the Vero cell line as well as on experimental rats. The lipid profile in all the diabetic groups (DG1-3) were significantly increased compared with both of the control groups (p < 0.05). The present study revealed the significance of C. AgNPs in nanotherapeutics.

Monascus spp. and citrinin: Identification, selection of Monascus spp. isolates, occurrence, detection and reduction of citrinin during the fermentation of red fermented rice

Red fermented rice (RFR) is rice fermented using Monascus spp. This product contains monacolin K, providing health benefits including mitigation of diarrhoea and improving blood circulation. RFR can produce pigments that can act as natural colour and flavouring agents. However, Monascus spp. (a fungal starter to ferment RFR) can also produce the mycotoxin, citrinin (CIT) which is believed to have adverse effects on human health. CIT in RFR has been reported worldwide by using different methods of detection. This review focuses on the production of RFR by solid-state fermentation (SSF) and submerged fermentation (SmF), the occurrence of CIT in RFR, CIT quantification, the factors affecting the growth of Monascus spp., pigments and CIT production in RFR, and possible methods to reduce CIT in RFR. This review will help the food industries, researchers, and consumers understand the risk of consuming RFR, and the possibility of controlling CIT in RFR.

Increased Water-Soluble Yellow Monascus Pigment Productivity via Dual Mutagenesis and Submerged Repeated-Batch Fermentation of Monascus purpureus

Monascus pigments (MPs) have been used in the food industry for more than 2,000 years and are known for their safety, bold coloring, and physiological activity. MPs are mainly yellow (YMPs), orange (OMPs), and red (RMPs). In this study, a mutant strain Monascus purpureus H14 with high production of water-soluble YMPs (WSYMPs, λ_max at 370 nm) was generated instead of primary YMPs (λ_max at 420 nm), OMPs (λ_max at 470 nm), and RMPs (λ_max at 510 nm) produced by the parent strain M. purpureus LQ-6 through dual mutagenesis of atmospheric and room-temperature plasma and heavy ion beam irradiation (HIBI), producing 22.68 U/ml extracellular YMPs and 10.67 U/ml intracellular YMPs. WSYMP production was increased by 289.51% in optimal conditions after response surface methodology was applied in submerged fermentation. Application of combined immobilized fermentation and extractive fermentation improved productivity to 16.89 U/ml/day, 6.70 times greater than with conservative submerged fermentation. The produced WSYMPs exhibited good tone stability to environmental factors, but their pigment values were unstable to pH, light, and high concentrations of Ca²⁺, Zn²⁺, Fe²⁺, Cu²⁺, and Mg²⁺. Furtherly, the produced exYMPs were identified as two yellow monascus pigment components (monascusone B and C₂₁H₂₇NO₇S) by UHPLC-ESI-MS. This strategy may be extended to industrial production of premium WSYMPs using Monascus.

Biosynthesis and polyketide oxidation of Monascus red pigments in an integrated fermentation system with microparticles and surfactants

Monascus red pigments are widely used in the food industry, mainly as intracellular red pigments. The low yields of extracellular red pigments (ERPs) make them unsuitable for large-scale industrial production. Herein, a novel integrated fermentation system (IFS) consisting of sodium starch octenyl succinate and Triton X-100 was explored for increasing yield, resulting in an ERP yield of 126.7 U/mL, 82.6% higher production than controls (69.4 U/mL). Major ERP components in control fermentations were monascopyridine A and monascopyridine B, but dehydro derivatives, rubropunctamine and monascorubramine, predominated in the test fermentations, presumably due to polyketide oxidation induced by Triton X-100. Improvement of hyphal morphology, membrane permeability, respiratory activity, and gene expression for red pigment biosynthesis is likely to be critical to increase yield and change the compositions. This study provides an effective strategy to accelerate the biosynthesis and secretion of Monascus pigments.

Analysis of the differences in the chemical composition of monascus rice and highland barley monascus

Monascus rice (MR) and highland barley monascus (HBM), the monascus fermented products, are applied in food and medicine to reduce cholesterol and promote digestion. Due to the fermentation substrates, their compositions are different. However, the exact differences have not been reported to date. By UPLC-Q-Orbitrap HRMS analysis, multiple components of twenty batches of MR and HBM samples were identified. In total, 100 components were confirmed (e.g., monacolins, pigments, decalin derivatives, amino acids). Then, principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) were used to filter the components of MR and HBM. In the PCA model, 88.1% of the total variance was uncovered. The OPLS-DA model showed better discrimination between MR and HBM, and the values of R²X, R²Y, and Q² were 0.837, 0.996, and 0.956, respectively. Based on the value of the variable importance in projection (VIP) and the result of the t-test, 424 components (VIP > 1, p < 0.05) were acquired. Finally, 11 differential components were selected as the characteristic compounds to discriminate between MR and HBM: the content of 9 monacolins (3-hydroxy-3,5-dihydrodehydromonacolin K, monacolin K, dehydromonacolin K, dehydromonacolin J hydroxy acid, monacophenyl, dihydromonacolin J hydroxy acid, monacolin L, dehydromonacolin J, and monacolin R) in HBM was higher than the content in MR, but the content of 2 pigments (ankaflavin and monascin) was lower in HBM and higher in MR. The findings revealed the similarities and differences in the chemical composition between MR and HBM, which is expected to provide a basis for quality control of HBM.

Red yeast rice dietary intervention reduces oxidative stress-related inflammation and improves intestinal microbiota

Inflammation and oxidative stress play key roles in the aging process, while red yeast rice (RYR), a traditional Chinese fermented food, has anti-oxidant and anti-inflammatory effects. To understand the anti-aging function of RYR in vivo, this study established a D-galactose-induced aging mouse model to verify the positive effects of RYR dietary intervention on aging and explore the related underlying mechanism. Eight weeks of RYR dietary intervention was shown to have a significant inhibitory effect on cognitive decline and hippocampal damage. The molecular mechanistic studies showed that the anti-aging effects of RYR were achieved by (i) improving the oxidative stress-related damage (increasing SOD, CAT, and GSH, and reducing MDA), (ii) regulating the NF-κB inflammation pathway induced by oxidative stress (decreasing the pro-inflammatory cytokines IL-6, TNF-α, IFN-γ, iNOs, and IL-1β, increasing the anti-inflammatory cytokine IL-10, and decreasing the expression of the NF-κB protein), (iii) slowing down apoptosis caused by oxidative stress (reducing the expression of P21 and P53), (iv) restoring the abundance of Lactobacillus, Lachnospiraceae and Rikenellaceae downregulated by D-galactose, and (v) reducing the abundance of Akkermansia and Helicobacter enriched by D-galactose. Mass spectrometry revealed orange pigments (rubropunctatin and monascorubrin) as the main antioxidant components in RYR, which might play key roles in aging inhibition. This study provides theoretical support for the wide application of orange pigments as an antioxidant dietary supplement.

Coconut Cream Agar as a simple and rapid semiquantitative method to screen citrinin-producing Monascus spp. isolates isolated from red fermented rice

Red fermented rice (RFR) is produced using Monascus spp. This product has some health benefits. However, RFR can also contain the mycotoxin, citrinin (CIT) and that has adverse effects on human health. The objective of the study was to develop a simple and rapid screening method for the detection of Monascus spp. isolates that can produce CIT by using Coconut Cream Agar (CCA). RFR was spread onto CCA and other media and incubated at 30 °C for 7 days. All the media were observed daily under ultraviolet (UV) light and any Monascus spp. colony that produced light blue fluorescence was recorded as a CIT-producer. Two different isolates (MF1 and MS1) isolated from CCA were selected for further analysis. All (100%; 10/10 plates) of CCA inoculated with MF1 produced light blue fluorescence after incubation for 4 days, meanwhile 30% (3/10 plates) of MS1 produced weak fluorescence on CCA after incubation for 7 days. Isolates MF1 and MS1 were identified as M. purpureus with the ability to produce CIT by having polyketide synthase (pksCT) and transcriptional regulator (ctnA) genes. CIT was quantified by high-performance liquid chromatography (HPLC). CCA is a simple and rapid method to detect CIT-producers of Monascus spp.

Natural Sources, Pharmacological Properties, and Health Benefits of Daucosterol: Versatility of Actions

Daucosterol is a saponin present in various natural sources, including medicinal plant families. This secondary metabolite is produced at different contents depending on species, extraction techniques, and plant parts used. Currently, daucosterol has been tested and explored for its various biological activities. The results reveal potential pharmacological properties such as antioxidant, antidiabetic, hypolipidemic, anti-inflammatory, immunomodulatory, neuroprotective, and anticancer. Indeed, daucosterol possesses important anticancer effects in many signaling pathways, such as an increase in pro-apoptotic proteins Bax and Bcl2, a decrease in the Bcl-2/Bax ratio, upregulation of the phosphatase and tensin homolog (PTEN) gene, inhibition of the PI3K/Akt pathway, and distortion of cell-cycle progression and tumor cell evolution. Its neuroprotective effect is via decreased caspase-3 activation in neurons and during simulated reperfusion (OGD/R), increased IGF1 protein expression (decreasing the downregulation of p-AKT3 and p-GSK-3b4), and activation of the AKT5 signaling pathway. At the same time, daucosterol inhibits key glucose metabolism enzymes to keep blood sugar levels within normal ranges. Therefore, this review describes the principal research on the pharmacological activities of daucosterol and the mechanisms of action underlying some of these effects. Moreover, further investigation of pharmacodynamics, pharmacokinetics, and toxicology are suggested.

Effects of mokF gene deletion and overexpression on the Monacolin K metabolism yields of Monascus purpureus

Monascus purpureus is a fungus known for producing various physiologically active secondary metabolites. Of these, Monacolin K, a compound with hypocholesterolemic effects, is controlled by the biosynthetic gene mokF. Here, mokF deletion and overexpression strains (F2 and C3, respectively) were constructed using genetic engineering and compared with the M. purpureus wild strain (M1). The results showed that Monacolin K production was reduced by 50.86% in F2 and increased by 74.19% in C3. Of the three strains, C3 showed the highest production of Monacolin K and the most abnormal morphology. In addition, mokF influenced the expression level of mokA-mokI and might play an important role in regulating the biosynthesis of secondary metabolites in M. purpureus. Overall, our study verified the function of mokF in M. purpureus using gene deletion and overexpression technology. KEY POINTS: • The deletion and overexpression strains of mokF gene were successfully constructed. • The deletion or overexpression of mokF gene directly affected Monacolin K production. •The mokF gene had little effect on Monascus pigments and cell biomass.

The biological activity and application of Monascus pigments: a mini review

Monascus pigments (MPs), as secondary metabolites of Monascus, are microbial pigments which have been used for thousands of years. MPs are widely used in food industry as food pigments and preservatives, which have the stability of light resistance, high temperature resistance and acid-base change resistance. In addition, the antioxidant, antibacterial, antiviral and anti-tumor biological activities of MPs have also attracted people’s attention. Moreover, Due to the presence of citrinin, the safety of MPs still needs to be discussed and explored. In this paper, the production, biological activity, application in various fields and methods of detection and reduction of citrinin of MPs were reviewed, which provide new insights into the study and safe application related to human different diseases, medicines or health care products with MPs as active substances.

Therapeutic Potential of Natural Plants Against Non-Alcoholic Fatty Liver Disease: Targeting the Interplay Between Gut Microbiota and Bile Acids

Non-alcoholic fatty liver disease (NAFLD) remains a common disease with a significant health and economic burden worldwide. The gut microbiota (GM) and bile acids (BAs), which play important roles in the gut-liver axis, have been confirmed to jointly participate in the development of NAFLD. GM not only regulate bile acids’ synthesis, transport, and reabsorption by regulating other metabolites (such as trimetlyl amine oxide, butyrate), but also regulate dehydrogenation, dehydroxylation and desulfurization of bile acids. Meanwhile, disordered bile acids influence the gut microbiota mainly through promoting the bacterial death and lowering the microbial diversity. Although weight loss and lifestyle changes are effective in the treatment of NAFLD, the acceptability and compliance of patients are poor. Recently, increasing natural plants and their active ingredients have been proved to alleviate NAFLD by modulating the joint action of gut microbiota and bile acids, and considered to be promising potential candidates. In this review, we discuss the efficacy of natural plants in treating NAFLD in the context of their regulation of the complex interplay between the gut microbiota and bile acids, the crosstalk of which has been shown to significantly promote the progression of NAFLD. Herein, we summarize the prior work on this topic and further suggest future research directions in the field.

Red Yeast Rice for Hyperlipidemia: A Meta-Analysis of 15 High-Quality Randomized Controlled Trials

Background: RYR is a commonly used lipid-lowering dietary supplements in Asian and European countries, showing considerable benefits and low toxicity. This quantitative study aims to present high-quality evidence regarding the efficacy and safety of RYR in treating hyperlipidemia, in order to promote its clinical application. Methods: PubMed, embase, and Cochrane Central Register of Controlled Trials databases were systematically searched, and high-quality randomized controlled trials comparing RYR with non-RYR interventions were included. RevMan5.3 software was used to conduct the meta-analysis. Results: A total of 1,012 individuals participated in this study (481 in the experimental and 531 in the control group). In comparison to statins, RYR was more effective in lowering TG (MD, -19.90; 95% CI, -32.22 to -7.58; p = 0.002), comparable in lowering LDL-C and elevating HDL-C, and less effective in lowering TC (MD, 12.24; 95% CI, 2.19 to 22.29; p = 0.02). Compared with nutraceutical, RYR significantly reduced TC (MD, -17.80; 95% CI, -27.12 to -8.48; p = 0.0002) and LDL-C (MD, -14.40; 95% CI, -22.71 to -6.09; p = 0.0007), and elevated HDL-C (MD, 7.60; 95% CI, 4.33 to 10.87; p < 0.00001). Moreover, RYR effectively synergized nutraceutical to further reduce TC (MD, -31.10; 95% CI, -38.83 to -23.36; p < 0.00001), LDL-C (MD, -27.91; 95% CI, -36.58 to -19.24; p < 0.00001), and TG (MD, -26.32; 95% CI, -34.05 to -18.59; p < 0.00001). Additionally, RYR significantly reduced apoB (MD, -27.98; 95% CI, -35.51 to -20.45; p < 0.00001) and, whether alone or in combination, did not increase the risk of adverse events in patients with hyperlipidemia. Conclusion: RYR at 200-4800 mg daily appears to be a safe and effective treatment for hyperlipidemia, effectively regulating blood lipid levels with an exceptional impact on TG. Looking forward, high-quality clinical trials with longer observation periods are required to evaluate the efficacy and safety of RYR as a long-term medication. Systematic Review Registration: (https://www.crd.york.ac.uk/PROSPERO/), identifier (CRD4202128450).

Effects of a Novel Magnesium Complex on Metabolic and Cognitive Functions and the Expression of Synapse-Associated Proteins in Rats Fed a High-Fat Diet

This study was conducted to compare the effects of a novel form of magnesium, Mg picolinate (MgPic), to magnesium oxide (MgO) on metabolic and cognitive functions and the expression of genes associated with these functions in rats fed a high-fat diet (HFD). Forty-two Wistar rats were divided into six groups: control, MgO, MgPic, HFD, HFD + MgO, and HFD + MgPic. Mg was supplemented at 500 mg of elemental Mg/kg diet for 8 weeks. MgPic and MgO supplementation decreased visceral fat, serum glucose, insulin, leptin, TC, TG, FFA, testosterone, FSH, LH, SHBG, IGF-1, and MDA levels, but increased brain SOD, CAT, and GSH-Px activities in HFD rats. Inflammation and cognitive-related markers (presynaptic synapsin PSD95, postsynaptic PSD93, postsynaptic GluR1, and GluR2) were improved in HFD rats administered Mg, with more significant effects seen in the MgPic group. MgPic also decreased brain NF-κB but elevated brain Nrf2 levels, compared with the HFD group. The phosphorylation levels of Akt (Thr308), Akt (Ser473), PI3K try 458/199, and Ser9-GSK-3 in the brain were improved after Mg treatment in HFD rats, with more potent effects seen from MgPic supplementation. MgPic has a higher bioavailability and is more effective in improving metabolic parameters and enhancing memory than MgO. The pro-cognitive effects of MgO and MgPic could be mediated via modulation of the AMPA-type glutamate receptor and activation of the PI3K-Akt-GSK-3β signaling pathway. These findings further support the use of MgPic in the management of metabolic and cognitive disorders.

Polygoni Multiflori Radix Praeparata Ethanol Extract Exerts a Protective Effect Against High-Fat Diet Induced Non-Alcoholic Fatty Liver Disease in Mice by Remodeling Intestinal Microbial Structure and Maintaining Metabolic Homeostasis of Bile Acids

In the prescription of Traditional Chinese Medicine for lipid metabolism, Polygoni Multiflori Radix Preparata (ZhiHeShouWu, RPMP) was widely used. In recent years, RPMP ethanol extract has been reported for the treatment of non-alcoholic fatty liver disease (NAFLD). However, the role of RPMP ethanol extract in the treatment of NAFLD has not been fully elucidated. Therefore, we examined the optimal therapeutic dose of RPMP ethanol extracts. Afterward, a mouse model of non-alcoholic fatty liver induced by a high-fat diet (HFD) was treated with RPMP ethanol extract to further evaluate the mechanism of action of RPMP ethanol extract treatment. And the serum lipid metabolism indexes and liver function indexes showed that the RPMP ethanol extract in the 1.35 g/kg dose group exhibited better therapeutic effects than the 2.70 g/kg dose group. Meanwhile, RPMP ethanol extract can regulate the biochemical indicators of serum and liver to normal levels, and effectively reduce liver steatosis and lipid deposition. RPMP ethanol extract treatment restored HFD-induced disruption of the compositional structure of the intestinal microbial (IM) and bile acids (BAs) pools. And restore the reduced expression of intestinal barrier-related genes caused by HFD administration, which also effectively regulates the expression of genes related to the metabolism of BAs in mice. Thus, RPMP ethanol extract can effectively improve the abnormal lipid metabolism and hepatic lipid accumulation caused by HFD, which may be related to the regulation of IM composition, maintenance of intestinal barrier function, and normal cholesterol metabolism in the body.

Integrative Metabolomic and Transcriptomic Analyses Uncover Metabolic Alterations and Pigment Diversity in Monascus in Response to Different Nitrogen Sources

Nitrogen in different chemical forms is critical for metabolic alterations in Monascus strains and associated pigment diversity. In this study, we observed that ammonium-form nitrogen was superior in promoting the biosynthesis of Monascus pigments (MPs) when compared with nitrate and organic forms. Moreover, with any nitrogen source, the production of yellow and orange pigments was highly synchronized but distantly related to red pigments. However, transcriptional analyses of MP gene clusters suggested a low contribution to MP accumulation, suggesting that MP-limiting factors were located outside the gene cluster. Our metabolomic analyses demonstrated that red pigment biosynthesis was closely related to intracellular amino acids, whereas orange and yellow pigments were associated with nucleotides. In addition, weighted gene coexpression network analyses (WGCNA) based on transcriptomic data showed that multiple primary metabolic pathways were closely related to red pigment production, while several secondary pathways were related to orange pigments, and others were involved with yellow pigment regulation. These findings demonstrate that pigment diversity in Monascus is under combined regulation at metabolomic and transcriptomic levels. IMPORTANCE Natural MPs containing a mixture of red, orange, and yellow pigments are widely used as food coloring agents. MP diversity provides foods with versatile colors and health benefits but, in turn, complicate efforts to achieve maximum yield or desirable combination of pigments during the manufacturing process. Apart from the MP biosynthetic gene cluster, interactions between the main biosynthetic pathways and other intracellular genes/metabolites are critical to our understanding of MP differentiation. The integrative multiomics analytical strategy provides a technical platform and new perspectives for the identification of metabolic shunting mechanisms in MP biosynthesis. Equally, our research highlights the influence of intracellular metabolic alterations on MP differentiation, which will facilitate the rational engineering and optimization of MP production in the future.

The beneficial effects of Lactobacillus brevis FZU0713-fermented Laminaria japonica on lipid metabolism and intestinal microbiota in hyperlipidemic rats fed with a high-fat diet

This study aimed to investigate the beneficial effects of the oral administration of Lactobacillus brevis FZU0713-fermented Laminaria japonica (FLJ) on lipid metabolism and intestinal microbiota in hyperlipidemic rats fed with a high-fat diet (HFD). The results demonstrated that the oral administration of FLJ significantly inhibited obesity and improved the serum and hepatic biochemical parameters in HFD-fed rats. Histopathological results also indicated that FLJ intervention could significantly reduce the accumulation of lipid droplets in the liver induced by HFD feeding. Furthermore, FLJ intervention up-regulated the fecal short-chain fatty acid (SCFA) levels (mainly acetate, propionate and isobutyrate) in HFD-fed rats. Intestinal microbiota profiling by 16S rRNA gene sequencing revealed that FLJ intervention increased the relative abundance of Akkermansia, Collinsella, Ruminococcaceae_UCG-013, Defluviitaleaceae_UCG-011, Intestinimonas, Actinomyces and Tyzzerella, but decreased the abundance of Flavonifractor, Collinsella, Sporosarcina and Lacticigenium. Based on Spearman's correlation, the fecal levels of TC, TG, acetic acid and butyric acid were positively correlated with the relative abundance of Akkermansia and Ruminococcaceae_NK4A214, but negatively correlated with the relative amount of Flavonifractor and Collinsella. The metabolic function of intestinal microbiota predicted by PICRUSt analysis of 16S rRNA gene sequences demonstrated that primary and secondary bile acid biosyntheses, fatty acid biosynthesis, taurine and hypotaurine metabolism, arachidonic acid metabolism, glycolysis/gluconeogenesis, etc. were significantly down-regulated after 8 weeks of FLJ intervention. Additionally, FLJ intervention significantly regulated the hepatic mRNA levels (including BSEP, CYP7A1, LDLR, HMGCR, CD36 and SREBP1-C) involved in lipid metabolism and bile acid homeostasis. In conclusion, these findings support the possibility that Laminaria japonica fermented with probiotic Lactobacillus has the potential to reduce the disturbance of lipid metabolism by regulating intestinal microflora and liver gene expression profiles, so it can be employed as a potential functional food to prevent hyperlipidemia.

Spirulina platensis polysaccharides attenuate lipid and carbohydrate metabolism disorder in high-sucrose and high-fat diet-fed rats in association with intestinal microbiota

This study aimed to evaluate the possibility that Spirulina platensis crude polysaccharides may ameliorate the lipid and carbohydrate metabolism disorder, including obesity, hyperlipidemia, hyperglycemia, hepatic steatosis, and gut dysbiosis. The results showed Spirulina platensis crude polysaccharides could improve body weight, serum/liver lipid and carbohydrate indexes, and liver antioxidant parameters in high-sucrose and high-fat diet (HFD)-fed rats, which were accompanied by regulated liver mRNA expressions involved in lipid and carbohydrate metabolism disorder. In addition, SPLP intervention significantly decreased cecal level of propionic acid in HFD-fed rats. Notably, the SPLP could alter the relative abundance of Firmicutes, Bacteroides, Proteobacteria, and Actinobacteria at phylum levels. Based on Spearman's rank correlation coefficient, serum/liver lipid and carbohydrate profiles were found significantly positively correlated with genera Romboutsia, Allobaculum, Blautia, Phascolarctobacterium, Bifidobacterium, Coprococcus, Turicibacter, Erysipelotrichaceae_unclassified, Olsenella, Escherichia/Shigella, Coprobacillus, Lachnospiracea incertae, and Lactobacillus, but strongly negatively correlated with genera Atopostipes, Flavonifractor, Porphyromonadaceae_unclassified, Barnesiella, Oscillibacter, Paraprevotella, Jeotgalicoccus, Corynebacterium, Alloprevotella and Bacteroides. It was concluded that oral administration of SPLP could remarkably ameliorate the lipid and carbohydrate metabolism disorder and significantly modulate the intestinal microbiota in HFD-fed rats.

Comparative Study on the Antioxidant Activity of Monascus Yellow Pigments From Two Different Types of Hongqu-Functional Qu and Coloring Qu

This study is the first to investigate the difference in the composition of Monascus azaphilone pigments (MonAzPs) between functional Qu (FQ) and coloring Qu (CQ) and analyze their relationships with antioxidant activity. The composition of key active components and antioxidant activity of the ethanol extracts of FQ and CQ were analyzed by Uv-vis, HPLC, and chemical antioxidant tests. The composition of MonAzPs of the ethanol extracts was further analyzed by HPLC-MS. Seven Monascus yellow pigments (MYPs) with high abundance were successfully purified for the antioxidation evaluation in vitro and in the cell. Correlation analysis between the metabolites and the antioxidant activity of Hongqu indicated that MonAzPs might play an essential role in the antioxidant activity (r > 0.80). By contrast, the monacolin K (MK), polysaccharide, ergosterol, and γ-aminobutyric acid (GABA) were not significantly correlated with the antioxidant activity. Orthogonal partial least squares discriminant analysis (OPLS-DA) based on the composition of MonAzPs revealed that the abundance of MYPs is significantly different between FQ and CQ (P < 0.05 and VIP > 1.0). Seven MYPs (monasfluore A, monaphilone B, monascuspilion, monascin, monaphilone A, ankaflavin, and new yellow pigment) with high abundance were successfully purified for the antioxidation evaluation. Chemical antioxidant tests revealed that the antioxidant activities of monaphilone A, ankaflavin, and new yellow pigment only from CQ were significantly more potent than monasfluore A and monascuspilion only separated from FQ. The cellular antioxidant assay (CAA) showed that the new yellow pigment had the best antioxidant activity (quercetin equivalent 7.23 μM), followed by monasfluore A and monaphilone B, all of which were significantly better than monascin and ankaflavin, the two most frequently reported MYPs. Research on the structure-activity relationship demonstrated that alterations of the hydroxyl that occurred on C-3' or C-11 obviously affected the antioxidant activities of MYPs. Our findings provide evidence that MYPs may be the key active components for CQ to have a more potent antioxidant capacity than FQ. The alterations of the hydroxyl that occurred on C-3' or C-11 obviously affected the antioxidant activities of MYPs.

Development of a Novel Restrictive Medium for Monascus Enrichment From Hongqu Based on the Synergistic Stress of Lactic Acid and Ethanol

Hongqu is a famous fermented food produced by Monascus and has been used as food coloring, wine starters and food additives for thousands of years in China. Excellent Monascus strain is an important prerequisite for producing high-quality Hongqu. However, the isolation of Monascus pure culture from Hongqu samples is time-consuming and laborious because it is easily interfered by other microorganisms (especially filamentous fungi). Therefore, the development of restrictive medium for Monascus enrichment from Hongqu is of great significance for the preparation and screening of excellent Monascus strains. Results of this study showed that Monascus has good tolerance to lactic acid and ethanol. Under the conditions of tolerance limits [7.5% lactic acid (v/v) and 12.0% ethanol (v/v)], Monascus could not grow but it still retained the vitality of spore germination, and the spore activity gradually decreased with the increasing concentrations of lactic acid and ethanol. More interestingly, the addition of lactic acid and ethanol significantly changed the microbial community structure in rice milk inoculated with Hongqu. After response surface optimization, Monascus could be successfully enriched without the interference of other microorganisms when 3.98% (v/v) lactic acid and 6.24% (v/v) ethanol were added to rice milk simultaneously. The optimal enrichment duration of Monascus by the restrictive medium based on the synergistic stress of lactic acid and ethanol is 8∼24 h. The synergistic stress of lactic acid and ethanol had no obvious effects on the accumulation of major metabolites in the progeny of Monascus, and was suitable for the enrichment of Monascus from different types of Hongqu. Finally, the possible mechanisms on the tolerance of Monascus to the synergistic stress of lactic acid and ethanol were preliminarily studied. Under the synergistic stress of lactic acid and ethanol, the cell membrane of Monascus defends against lactic acid and ethanol into cells to some extent, and the superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities of Monascus were higher than those of other fungi, which significantly reduced the degree of lipid peroxidation of cell membrane, while secreting more amylase to make reducing sugars to provide the cells with enough energy to resist environmental stress. This work has great application value for the construction of Monascus strain library and the better development of its germplasm resources.

A facile macroporous resin-based method for separation of yellow and orange Monascus pigments

The yellow Monascus pigments (YMPs) named monascin and ankaflavin and the orange Monascus pigments (OMPs) named rubropunctatin and monascorubrin are two groups of bioactive components in a mixture state in the Monascus fermented products. In order to separate these two groups of bioactive pigments, a facile macroporous resin-based method was developed. The weak-polar resin CAD-40 was selected from the seven tested macroporous resins as it revealed better properties for the adsorption and desorption of the YMPs and OMPs. Then, CAD-40 resin was used for column-chromatographic separation. After eluted by 4 bed volumes of ethanol, the yellow group (monascin and ankaflavin) and the orange group (rubropunctatin and monascorubrin) were successfully separated and purified, with an increased content from 49.3% and 44.2% in the crude pigment extract to 85.2% and 83.0% in the final products, respectively. This method would be helpful for the large-scale separation and purification of Monascus pigment products with specific bioactivity.

GC × GC-MS analysis and hypolipidemic effects of polyphenol extracts from Shanxi-aged vinegar in rats under a high fat diet

Oxidative stress, inflammation and gut microbiota disorders can be induced by long-term high-fat diets (HFD). In order to confirm that polyphenols can improve these symptoms, polyphenols from Shanxi-aged vinegar (SAVEP) were extracted, and the components were detected by Comprehensive two-dimensional gas chromatography mass spectrometry (GC × GC-MS). 41 polyphenols include 18 phenolic acids and 17 polyphenols, which have not been reported. The mechanism of SAVEP on oxidative stress and inflammatory stress induced by HFD in rats and its regulating effect on intestinal flora disorder were studied. The results showed that SAVEP could significantly improve the lipid, inflammatory stress and oxidative stress related indicators compared with the Model group ("Model" refers to the group that successfully constructed a hyperlipidemia model by feeding HFD without any drugs or SAVEP in subsequent experiments.). In addition, SAVEP decreased the Firmicutes/Bacteroidetes ratio compared with the Model group, and elevated the relative abundance of beneficial bacteria. Conclusively, SAVEP can alleviate the oxidative stress and inflammatory stress caused by HFD, improving intestinal microbial disorders. The Spearman's correlation analysis revealed that Desulfovibrio, Lactobacillus and Akkermansia were correlated negatively with all of the inflammatory indicators, whereas Ruminococcus was the opposite. These results suggest that SAVEP may be a novel strategy against oxidative stress and inflammation, restoring the normal microbial community ecology of the gut and the treatment of metabolic syndromes.

Natural Pigments of Bacterial Origin and Their Possible Biomedical Applications

Microorganisms are considered one of the most promising niches for prospecting, production, and application of bioactive compounds of biotechnological interest. Among them, bacteria offer certain distinctive advantages due to their short life cycle, their low sensitivity to seasonal and climatic changes, their easy scaling as well as their ability to produce pigments of various colors and shades. Natural pigments have attracted the attention of industry due to an increasing interest in the generation of new products harmless to humans and nature. This is because pigments of artificial origin used in industry can have various deleterious effects. On this basis, bacterial pigments promise to be an attractive niche of new biotechnological applications, from functional food production to the generation of new drugs and biomedical therapies. This review endeavors to establish the beneficial properties of several relevant pigments of bacterial origin and their relation to applications in the biomedical area.

Red yeast rice prevents chronic alcohol-induced liver disease by attenuating oxidative stress and inflammatory response in mice

Alcoholic liver disease (ALD) is characterized by dyslipidemia, hepatic steatosis, steatohepatitis, edema, necrosis, etc. Studies have reported that some dietary nutrition factors have beneficial effects in improving ALD. Red yeast rice (RYR), a traditional herbal supplement, has been confirmed to lower cholesterol mainly due to its component monacolin K. However, the effect of RYR on ALD has not been investigated. In this study, mice were supplemented with a daily oral gavage of 4 g/kg 50% ethanol for 8 weeks to induce a chronic ALD. RYR (150 mg kg^-1  day^-1 ) was supplied to ALD mice in treatment group. The results showed that RYR supplementation significantly attenuated hyperlipidemia, elevated circulating inflammatory cytokines, hepatic structural damage, and oxidative stress in mice supplemented with alcohol with no effects on body weight. Moreover, RYR significantly suppressed alcohol-induced hepatic NF-κB activation and apoptosis. Our results suggest that RYR is capable of preventing ALD mainly by attenuating hepatic oxidative stress and inflammatory response. PRACTICAL APPLICATIONS: RYR was known for cholesterol-lowering effect through its main component monacolin K. The current study revealed that RYR was capable of ameliorating ALD, which is characterized by profound dyslipidemia, hepatic steatosis, steatohepatitis, edema, etc. Our results indicated that the protective effect of RYR on ALD is largely achieved by regulating lipid metabolism, and closely related to the anti-inflammatory and antioxidant effects of RYR. This study provides research foundation for the development of RYR-related food or pharmaceutical products, especially targeting for ALD.

Inducing red pigment and inhibiting citrinin production by adding lanthanum(III) ion in Monascus purpureus fermentation

Monascus pigments (MPs) are widely used natural colorants in Asian countries. The problems of low extracellular red pigment (ERP) and high citrinin remain to be solved in Monascus pigment production. The effect of lanthanum(III) ion (LaCl₃) on Monascus purpureus fermentation was investigated in this study. The yields of ERP and biomass respectively reached maxima of 124.10 U/mL and 33.10 g/L by adding 0.4 g/L La³⁺ on the second day in the total 8-day fermentation; simultaneously, citrinin was decreased by 59.93% and 38.14% in the extracellular and intracellular fractions, respectively. Reactive oxygen species (ROS) levels were obviously improved by La³⁺ treatment, while the activities of catalase (CAT) and superoxide dismutase (SOD) were increased compared with the control. The ratio of unsaturated/saturated fatty acids in mycelia was increased from 2.94 to 3.49, indicating that the permeability and fluidity of the cell membrane were enhanced under La³⁺ treatment. Gene expression analysis showed that the relative expression levels of Monascus pigment synthesis genes (pksPT, mppB, mppD, MpFasB2, and MpPKS5) were significantly upregulated by La³⁺ treatment, and in contrast, the relative expression levels of citrinin synthesis genes (ctnA, pksCT and mppC) were markedly downregulated. This work confirmed that LaCl₃ possesses the potential to induce red pigment biosynthesis and inhibit citrinin production in M. purpureus fermentation. KEY POINTS: • La³⁺ induced red pigment and inhibited citrinin production in Monascus fermentation. • La³⁺ regulated genes expression up for Monascus pigment and down for citrinin. • La³⁺ increased the UFAs in cell membrane to enhance the permeability and fluidity.

Screening and evaluation of Monascus purpureus FJMR24 for enhancing the raw material utilization rate in rice wine brewing

BACKGROUND

The rapid development of the rice wine industry has increased the demand for raw materials worldwide. A fungal strain with good adaptability to rice wine brewing conditions, which can also enhance the utilization rate of raw materials (URRM), thus increasing the production efficiency, was sought in the present research.

RESULTS

The strain FJMR24 was successfully isolated and screened from 35 fermentation starters and exhibited high amylase activity (2200.9 ± 18.5 U g^-1 ) and high glucoamylase activity (2330.4 ± 31.9 U g^-1 ). Based on a morphological examination and a sequence analysis of the internal transcribed spacer (ITS) gene and β-tubulin gene, FJMR24 was identified as Monascus purpureus, which is an edible and versatile fungus that plays a dominant role in the processing of Hong Qu. A moderate pH of 5-6 under incubation at 35 °C for 5-6 days was favorable for the growth and enzyme production of FJMR24. The strain could also tolerate the extreme conditions of 15-45 °C, 18% ethanol (v/v), and an acidity of pH 2. The excellent fermentation adaptability of FJMR24 might enable it to retain high enzyme activity during rice wine brewing. As a result of the action of FJMR24, the URRM of the base liquor increased by around 26% due to increased starch hydrolysis efficiency, which was mainly due to the high unit enzyme activity of FJMR24.

CONCLUSION

This study provides perspectives for the application of a M. purpureus strain with high starch hydrolysis activity for enhancing the URRM in traditional rice wine brewing. © 2020 Society of Chemical Industry.

DHA-enriched phospholipids from large yellow croaker roe regulate lipid metabolic disorders and gut microbiota imbalance in SD rats with a high-fat diet

Large yellow croaker roe phospholipids (LYCRPLs) have great nutritional value because they are rich in docosahexaenoic acid (DHA), which is an n-3 polyunsaturated fatty acid (n-3 PUFA). In previous research, we studied the effect of LYCRPLs on the inhibition of triglyceride accumulation at the cellular level. However, its lipid regulation effect in rats on a high-fat diet and its influence on the gut microbiota has not yet been clarified. In this study, a high-fat diet was used to induce the lipid metabolism disorder in SD rats, and simvastatin, low-dose, medium-dose and high-dose LYCRPLs were given by intragastric administration for 8 weeks. The rats' body weight, food intake, organ index, blood biochemical indicators, epididymal fat tissue and liver histopathology were compared and analyzed. High-throughput 16S rRNA gene sequencing technology and bioinformatics analysis technology were also used to analyze the diversity of gut microbiota in rats. We found that LYCRPLs can significantly regulate lipid metabolism, and improve the gut microbiota disorder induced in rats by a high-fat diet. These results can lay a foundation for the study of the regulation mechanism of LYCRPLs lipid metabolism, and also provide a theoretical basis for the development of LYCRPLs as functional food additives and excipients with hypolipidemic effects.

Medicinal Chemistry Friendliness of Pigments from Monascus-Fermented Rice and the Molecular Docking Analysis of Their Anti-Hyperlipidemia Properties

In this study, the physicochemical properties, pharmacokinetics properties, and drug-likeness of pigments from Monascus-fermented rice (Monascus pigments, MPs) were predicted in silico using SwissADME tool. In silico prediction of physicochemical properties showed that MPs had desirable lipophilic drug-like physicochemical properties including molecular weight (236 to 543), TPSA (44.76 to 179.77), lipophilicity (−0.81 to 4.14), and water solubility (−4.94 to −0.77). The pharmacokinetic properties of MPs (i.e., GIA, P-glycoprotein substrate, and CYP3A4 inhibitor) illustrated that most MPs had high intestinal absorption and bioavailability, but some MPs might cause pharmacokinetics-related drug–drug interactions. Following this, six main well-known MPs (monascin, ankaflavin, rubropunctatin, monascorubrin, rubropunctamine, monascorubramine) were selected for molecular docking with some enzyme receptors. The docking results were shown with the best molecular docking poses, and the interacting residues, number and distance of hydrogen bonds of the MPs and monacolin K (for docking with 3-hydroxy-3-methyl glutaryl coenzyme A reductase (HMG-CoA reductase)), or MPs and oleic acid (for docking with lipase). Dissociation constants showed that MPs had lower inhibitory potential for HMGR (compared with Monacolin K), and higher inhibitory potential for lipase. Individual pigments from Monascus-fermented rice, therefore, have the potential to be developed as drug candidates for controlling hyperlipidemia.

Pharmacokinetic-Pharmacodynamic Modeling of the Antioxidant Activity of Quzhou Fructus Aurantii Decoction in a Rat Model of Hyperlipidemia

BACKGROUND

Quzhou Fructus Aurantii (QFA) is an herb that is commonly used to alleviate inflammation in individuals dealing with obesity.To date, however, no systematic pharmacokinetic (PK) or pharmacodynamic (PD) analyses of the clinical efficacy of QFA under hyperlipemia-associated oxidative stress conditions have been conducted. The present study, was therefore designed to construct a PK-PD model for this herb, with the goal of linking QFA PK profiles to key therapeutic outlines to guide the therapeutic use of this herb in clinical settings.

METHODS

Rats were fed a high-fat diet in order to establish a model of hyperlipidemia, after which they were randomized into a normal control group (NCG), a normal treatment group (NTG), a model control group (MCG), and a model treated group (MTG) (n = 6 each). QAF decoction was used to treat rats in the NTG and MTG groups (25 g/kg), while equivalent volumes of physiological saline were administered to rats in the NCG and MCG groups. Plasma samples were collected from the mandibular vein for animals at appropriate time points and analyzed via high-performance liquid chromatography (HPLC). We evaluated PK properties for three QAF components and compared these dynamics between the NTG and MTG groups, while also measuring levels of lipid peroxidation (LPO) in the plasma of rats in all four treatment groups. We then constructed a PK-PD model based upon plasma neohesperidin, luteolin, and nobiletin concentrations and LPO levels using a three-compartment PK model together with a Sigmoid E_max PD model. This model thereby enabled us to assess the antioxidative impact of neohesperidin, luteolin, and nobiletin on hyperlipidemia in rats.

RESULTS

When comparing the NTG and MTG groups, we detected significant differences in the following parameters pertaining to neohesperidin, luteolin, and nobiletin:t_1/2β, V1,  t_1/2γ, CL1 (p < 0.01) and AUC_0-t, T_max, C_max (p < 0.05). Relative to NTG group rats, AUC_0-t, T_maxandC_maxvalues significantly higher for MTG group rats (p < 0.01), while t_1/2β, V1, and  t_1/2γ values were significantly lower in MTG group rats (p < 0.01) in MTG rats. QAF decoction also exhibited excellent PD efficacy in MTG rats, with significant reductions in plasma LPO levels relative to NTG rats (p < 0.01) following treatment. This therapeutic efficacy may be attributable to the activity of neohesperidin, luteolin, and nobiletin, as LPO levels and plasma concentrations of these compounds were negatively correlated in treated rats. Based upon Akaike Information Criterion (AIC) values, we determined that neohesperidin, luteolin, and nobiletin PK processes were consistent with a three-compartment model. Together, these findings indicated that three active components in QAF decoction (neohesperidin, luteolin, and nobiletin) may exhibit antioxidant activity in vivo.

CONCLUSION

Our in vivo data indicated that neohesperidin, luteolin and nobiletin components of QAF decoctions exhibit distinct PK and PD properties. Together, these findings suggest that hyperlipidemia-related oxidative stress can significantly impact QFA decoction PK and PD parameters. Our data additionally offer fundamental insights that can be used to design appropriate dosing regimens for individualized clinical QAF decoction treatment.