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Journal of Fungi (Basel, Switzerland) May 2024pigments (MPs), a class of secondary metabolites produced by spp., can be classified into yellow, orange, and red MPs according to their differences in the wavelength...
pigments (MPs), a class of secondary metabolites produced by spp., can be classified into yellow, orange, and red MPs according to their differences in the wavelength of the maximum absorption. However, the biosynthetic sequence and cellular biosynthesis mechanism of different MPs components are still not yet completely clear in spp. In this study, the subcellular localization of five MPs synthases was investigated using fluorescent protein fusion expression. The results revealed that the proteins encoded by the MPs biosynthetic gene cluster were compartmentalized in various subcellular locations, including the mitochondrial polyketide synthase MrPigA, cytosolic enzymes consisting of the ketoreductase MrPigC, the oxidoreductase MrPigE, and the monooxygenase MrPigN, and the cell-wall-bound oxidoreductase MrPigF. Moreover, the correct localization of MrPigF to the cell wall was crucial for the synthesis of orange MPs. Lastly, we discussed the compartmentalized biosynthetic pathway of MPs. This study will not only be helpful in clarifying the biosynthetic sequence and biosynthesis mechanism of different MPs but also provides new insights into the cellular biosynthesis of secondary metabolites in filamentous fungi.
PubMed: 38921362
DOI: 10.3390/jof10060375 -
CEN Case Reports Jun 2024A 62-year-old man visited his primary care physician with the complaints of loss of appetite and fatigue. He was admitted to our hospital based on a diagnosis of acute...
A 62-year-old man visited his primary care physician with the complaints of loss of appetite and fatigue. He was admitted to our hospital based on a diagnosis of acute kidney injury, Fanconi syndrome as indicated by hypokalemia, hypouricemia, hypophosphatemia, elevated glucose levels in urine, and aminoaciduria. He had been taking multiple supplements, including Red Yeast Rice Cholesterol Help®, for one and a half years. After admission, all the supplements were stopped. Blood samples were collected; however, the samples were negative for diseases that could cause Fanconi syndrome. Renal biopsy revealed renal proximal tubular damage, mainly characterized by simplification of the proximal tubular epithelium. The mycotoxin, citrinin, which is reported to be produced by the mold used for producing red yeast rice, but not the mold Monascus pilosus used for Red Yeast Rice Cholesterol Help, reportedly causes proximal tubular damage. However, although the causative agent has not been identified, it was thought that a substance similar to citrinin, produced by the mold used for Red Yeast Rice Cholesterol Help®, caused proximal tubular damage, leading to acute kidney injury and Fanconi syndrome. Hence, all supplements were stopped, and the patient was treated with oral potassium and phosphorus preparations, leading to gradual recovery of his kidney function. We herein report the first case of acute kidney injury and Fanconi syndrome in a patient taking multiple health supplements, including Red Yeast Rice Cholesterol Help®. Early discontinuation of the oral supplements was probably useful in improving the patient's kidney function.
PubMed: 38900361
DOI: 10.1007/s13730-024-00903-0 -
Plants (Basel, Switzerland) May 2024Enhancing the aerobic stability of whole-plant corn silage is essential for producing high-quality silage. Our research assessed the effect of inoculation with or and...
Enhancing the aerobic stability of whole-plant corn silage is essential for producing high-quality silage. Our research assessed the effect of inoculation with or and its modulation of the bacterial and fungal microbial community structure in an aerobic stage of whole-plant corn silage. Following treatment with a distilled sterile water control, , and (2 × 10 cfu/g), whole-plant corn was ensiled for 60 days. Samples were taken on days 0, 3, and 7 of aerobic exposure, and the results showed that inoculation with or improved the aerobic stability of silage when compared to the effect of the control ( < 0.05). Inoculation with attenuated the increase in pH value and the decrease in lactic acid in the aerobic stage ( < 0.05), reducing the filamentous fungal counts. On the other hand, inoculation with or increased the diversity of the fungal communities ( < 0.05), complicating the correlation between bacteria or fungi, reducing the relative abundance of and in bacterial communities, and inhibiting the tendency of to replace in fungal communities, thus delaying the aerobic spoilage process. Due to the prevention of the development of aerobic spoilage microorganisms, the silage injected with or exhibited improved aerobic stability.
PubMed: 38891280
DOI: 10.3390/plants13111471 -
Current Vascular Pharmacology Jun 2024Hypertension is associated with endothelial dysfunction. An imbalance in the production of Nitric Oxide (NO) and Reactive Oxygen Species (ROS), leading to impaired...
Chronic Administration of Red Yeast Rice Mitigates Endothelial Dysfunction in Spontaneously Hypertensive Rats by Inhibiting Oxidative Stress and Endothelial Nitric Oxide Synthase Uncoupling.
BACKGROUND
Hypertension is associated with endothelial dysfunction. An imbalance in the production of Nitric Oxide (NO) and Reactive Oxygen Species (ROS), leading to impaired NO-cyclic Guanosine Monophosphate (cGMP) pathway, contributes to this disorder. Red Yeast Rice (RYR), produced from the fermentation of rice with Monascus purpureus, is a traditional functional food originating from China. Although recognized for its anti-dyslipidemia properties, there has been growing evidence regarding the anti-hypertensive effects of RYR. However, these studies only focused on its direct and short-term effects.
AIM
This study aims to investigate the vasoprotective effects of chronic oral RYR administration using Spontaneously Hypertensive Rats (SHR).
MATERIALS AND METHODS
SHR were randomly divided into 3 groups: SHR - Control; SHR - RYR extract (100 mg/kg/day); SHR - lovastatin (10 mg/kg/day). Wistar-Kyoto Rats (WKY) were used as normotensive controls. All animals were treated for 12 weeks by oral gavage. Systolic Blood Pressure (SBP) was measured weekly (tail-cuff method). Vascular reactivity was determined using isolated rat aortic rings in an organ bath. Aortic ROS, NO, tetrahydrobiopterin (BH4 ), and cGMP levels were evaluated.
RESULTS
Administration of RYR attenuated SBP elevation and enhanced endothelium-dependent vasodilation in aortic rings. In addition, RYR decreased ROS production and significantly improved the level of vascular NO, BH4, and cGMP.
CONCLUSION
In an SHR model, treatment with RYR for 12 weeks exerts an SBP lowering effect that can be attributed to improved vascular function via reduction of oxidative stress, decreased endothelial NO Synthase (eNOS) uncoupling and enhanced NO-cGMP pathway.
PubMed: 38847159
DOI: 10.2174/0115701611295900240529104225 -
Heliyon Jun 2024Exploring the symbiotic potential between fungal and yeast species, this study investigates the co-cultivation dynamics of , a prolific producer of pharmacologically...
Exploring the symbiotic potential between fungal and yeast species, this study investigates the co-cultivation dynamics of , a prolific producer of pharmacologically relevant secondary metabolites, and . The collaborative interaction between these microorganisms catalyzed a substantial elevation in the biosynthesis of secondary metabolites, prominently Monacolin K and natural pigments. Central to our discoveries was the identification and enhanced production of oxylipins (13S-hydroxyoctadecadienoic acid,13S-HODE), putative quorum-sensing molecules, within the co-culture environment. Augmentation with exogenous oxylipins not only boosted Monacolin K production by over half but also mirrored morphological adaptations in , affecting both spores and mycelial structures. This augmentation was paralleled by a significant upregulation in the transcriptional activity of genes integral to the Monacolin K biosynthetic pathway, as well as genes implicated in pigment and spore formation. Through elucidating the interconnected roles of quorum sensing, G-protein-coupled receptors, and the G-protein-mediate signaling pathway, this study provides a comprehensive view of the molecular underpinnings facilitating these metabolic enhancements. Collectively, our findings illuminate the profound influence of co-culture on , advocating for oxylipins as a pivotal quorum-sensing mechanism driving the observed symbiotic benefits.
PubMed: 38845857
DOI: 10.1016/j.heliyon.2024.e31619 -
Food Chemistry May 2024Monascus species are functional fermentation fungi with great potential for selenium (Se) supplementation. This study investigated the effects of Se bio-fortification on...
Monascus species are functional fermentation fungi with great potential for selenium (Se) supplementation. This study investigated the effects of Se bio-fortification on the growth, morphology, and biosynthesis of Monascus ruber M7. The results demonstrated a significant increase in the yield of orange and red Monascus pigments (MPs) in red yeast rice (RYR) by 38.52% and 36.57%, respectively, under 20 μg/mL of selenite pressure. Meanwhile, the production of citrinin (CIT), a mycotoxin, decreased from 244.47 μg/g to 175.01 μg/g. Transcriptome analysis revealed significant upregulation of twelve genes involved in MPs biosynthesis, specifically MpigE, MpigF, and MpigN, and downregulation of four genes (mrr3, mrr4, mrr7, and mrr8) associated with CIT biosynthesis. Additionally, three genes encoding cysteine synthase cysK (LogFC = 1.6), methionine synthase metH (LogFC = 2.2), and methionyl-tRNA synthetase metG (LogFC = 1.8) in selenocompound metabolism showed significantly upregulated. These findings provide insights into Se biotransformation and metabolism in filamentous fungi.
PubMed: 38843715
DOI: 10.1016/j.foodchem.2024.139740 -
Food Chemistry May 2024Citrinin is a hepato-nephrotoxic mycotoxin produced by fungal species. The Monascus purpureus fungus plays a crucial role in the fermentation of red rice to produce red...
Development and validation of an analytical method for determination of citrinin in red rice and red yeast rice-based food supplements by ultra-high performance liquid chromatography tandem mass spectrometry.
Citrinin is a hepato-nephrotoxic mycotoxin produced by fungal species. The Monascus purpureus fungus plays a crucial role in the fermentation of red rice to produce red yeast rice-based food supplements, which represent the primary source of human exposure to citrinin. In this study, a simple and sensitive analytical method was successfully developed and validated for the citrinin determination in these products. The extraction process involved a QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) step and citrinin determination by ultra high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). The proposed method provided satisfactory linearity, percentage of recovery from 82 to 104% with relative standard deviations (RSD) lower than 14%, and limits of detection and quantification of 0.07 μg/Kg and 0.24 μg/kg, respectively. Among the 14 samples analyzed, citrinin was found in two red rice samples (0.24 and 0.46 μg/kg) and in six food supplements (from 0.44 to 87 μg/kg).
PubMed: 38843711
DOI: 10.1016/j.foodchem.2024.139941 -
Journal of Natural Medicines Jun 2024Recently, health hazards, such as kidney damage, have been reported owing to the ingestion of a health food product, so-called "foods with functional claims (FFC)'',...
Recently, health hazards, such as kidney damage, have been reported owing to the ingestion of a health food product, so-called "foods with functional claims (FFC)'', containing beni-koji (red yeast rice). Although not an expected compound in the FFC, the detection of puberulic acid has also been reported. Further investigations of these health food products, such as the identification of other unintended compounds and clarifying the health impacts of puberulic acid, are required. To clarify the causes of these health issues, we investigated the presence of unintended compounds in the FFC containing beni-koji using comprehensive instrumental analyses. Using differential analysis, novel compounds 1 and 2 were detected as unexpected components between the samples with and without adverse event reports. Although limited to the samples available for analyses in this study, both compounds 1 and 2 were detected in all the samples that also contained puberulic acid. Compounds 1 and 2, with molecular formulas of CHO and CHO, respectively, may be lovastatin derivatives. Their structures were confirmed using NMR analyses and are novel natural compounds. For definitive confirmation, we are in the process of synthesizing compounds 1 and 2 from lovastatin. The route of contamination of these compounds are currently under investigation. The findings of this study could be used to address the growing health hazards associated with health food products.
PubMed: 38834898
DOI: 10.1007/s11418-024-01827-w -
Food Research International (Ottawa,... Jul 2024The Monascus-fermented cheese (MC) is a unique cheese product that undergoes multi-strain fermentation, imparting it with distinct flavor qualities. To clarify the role...
The Monascus-fermented cheese (MC) is a unique cheese product that undergoes multi-strain fermentation, imparting it with distinct flavor qualities. To clarify the role of microorganisms in the formation of flavor in MC, this study employed SPME (arrow)-GC-MS, GC-O integrated with PLS-DA to investigate variations in cheese flavors represented by volatile flavor compounds across 90-day ripening periods. Metagenomic datasets were utilized to identify taxonomic and functional changes in the microorganisms. The results showed a total of 26 characteristic flavor compounds in MC at different ripening periods (VIP>1, p < 0.05), including butanoic acid, hexanoic acid, butanoic acid ethyl ester, hexanoic acid butyl ester, 2-heptanone and 2-octanone. According to NR database annotation, the genera Monascus, Lactococcus, Aspergillus, Lactiplantibacillus, Staphylococcus, Flavobacterium, Bacillus, Clostridium, Meyerozyma, and Enterobacter were closely associated with flavor formation in MC. Ester compounds were linked to Monascus, Meyerozyma, Staphylococcus, Lactiplantibacillus, and Bacillus. Acid compounds were linked to Lactococcus, Lactobacillus, Staphylococcus, and Bacillus. The production of methyl ketones was closely related to the genera Monascus, Staphylococcus, Lactiplantibacillus, Lactococcus, Bacillus, and Flavobacterium. This study offers insights into the microorganisms of MC and its contribution to flavor development, thereby enriching our understanding of this fascinating dairy product.
Topics: Cheese; Volatile Organic Compounds; Fermentation; Monascus; Food Microbiology; Taste; Metagenomics; Gas Chromatography-Mass Spectrometry; Bacteria; Flavoring Agents
PubMed: 38823869
DOI: 10.1016/j.foodres.2024.114483 -
International Journal of Biological... Jun 2024In recent years, the considerable potential of endophytic bacteria and fungi as prolific producers of exopolysaccharides (EPSs) have attracted interest. In this study,...
In recent years, the considerable potential of endophytic bacteria and fungi as prolific producers of exopolysaccharides (EPSs) have attracted interest. In this study, 56 endophytes were isolated from Cyclocarya paliurus, and the secondary metabolites of EPSs were extracted from Monascus purpureus, Penicillium citrinum and Aspergillus versicolor, screened, and named MPE, PCE and AVE, respectively. In this work, the physicochemical properties and antioxidant activities of three EPSs, their cell proliferation activity on IEC-6 and RAW264.7 were investigated. The three EPSs were mainly composed of neutral sugar and differ in microstructure. However, MPE had a loose structure, and PCE exhibited a dense and sheet-like structure. In addition, the three EPSs performed ordinary antioxidant activity in vitro but showed excellent cell proliferation activity on IEC-6 and RAW264.7. The cell proliferation activity of PCE was 1.4-fold that of the controls at a concentration of 800 μg/mL on IEC-6, and MPE exhibited 1.3-fold increase on RAW264.7. This study provided scientific evidence and insights into the application of endophytes as a novel plant resource possessing huge application potential.
Topics: Mice; Animals; Antioxidants; RAW 264.7 Cells; Endophytes; Cell Proliferation; Juglandaceae; Penicillium; Aspergillus; Fungal Polysaccharides; Monascus; Rats
PubMed: 38816295
DOI: 10.1016/j.ijbiomac.2024.132110