Dimerumic acid as an antioxidant of the mold, Monascus anka

Genome mining of albocandins A-E from Streptomyces sp. YINM00030

The natural products of 2,5-diketopiperazines have attracted considerable attention due to their potent pharmacological activities. Guided by genome mining techniques, five albonoursin analogues, designated as albocandins A-E (1-5), were isolated from Streptomyces sp. YINM00030, an actinomycete sourced from the rhizosphere soil of medicinal plants. The structures and absolute configurations of these compounds were elucidated through comprehensive spectroscopic analyses, HRESIMS, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction analyses. The biosynthetic pathway of these compounds were proposed. The investigation of biological activity showed that albocandins C and D exhibited cytotoxic activity against five human cancer cell lines (HL-60, A549, SMMC-7721, MDA-MB-231, SW480) in vitro with IC50 values ranging from 3.50 to 32.66 μM.

Monascus pigment prevent the oxidative cytotoxicity in myotube derived hydrogen peroxide

The amounts of Reactive oxygen species (ROS) become higher by strenuous exercises which consume larger amounts of oxygen in active muscles. Since these ROS directly injured muscles, the high ROS concentration involves muscle fatigue. Thus, an immediate ROS scavenging system in the muscle is desired. Since Monascus pigment (MP) involves physiologically active substances which scavenge ROS, it may be a clue to save the muscle injury. However, there are no reports examining MP effects on oxidative stress in skeletal muscle. In this study, we investigated the effect and mechanism of MP on skeletal muscle cells damaged by oxidative stress. The ability to directly eliminate ROS was evaluated by mixing MP solutions with •OH and O2 •-, a type of ROS. The effect of peroxidation in C2C12 cells was evaluated by cell viability assay and Western blotting. MP scavenges •OH and O2 •-. MP treatment increases the survival rate under oxidative stress. At that time, the expression of catalase was increased: the enzyme change H2O2 into H2O to rescue the cells under oxidative stress. We conclude that monascus pigment suppressed myotube damage under oxidative stress by both non-enzymatic ROS scavenging and up-regulation of catalase expression.

Rhodotorulic Acid and its Derivatives: Synthesis, Properties, and Applications

Siderophores are low molecular weight compounds produced by microorganisms to scavenge iron in iron-deficient environments. Rhodotorulic acid, a natural hydroxamate siderophore, plays a vital role in iron acquisition for fungi and bacteria. As the simplest natural hydroxamate siderophore, it exhibits a high affinity for ferric ions, enabling it to form stable complexes that facilitate iron uptake and transport within microorganisms. This article provides a comprehensive analysis of this hydroxamate siderophore, rhodotorulic acid, its synthesis, physicochemical properties, and biological significance. It also explores its applications in antifungal and plant protection strategies. Insights into RA derivatives reveal distinct biological effects and applications with potential in various fields, from antioxidants to antifungals. Rhodotorulic acid and its derivatives show promise for novel therapies, plant protection strategies, and iron supplementation in agriculture. Understanding their properties could advance science and medicine with sustainable practices.

Microbial diversity and functional genes of red vinasse acid based on metagenome analysis

Red vinasse acid has a distinct flavor and a vivid red color that are directly tied to the intricate metabolic activities of microorganisms that produce it. In this study, metagenomic technology was used to mine its functional genes and examine the microbial diversity of red vinasse acid. The findings revealed the identification of 2,609 species, 782 genera, and 63 phyla of microorganisms, and the dominant genus was Lactobacillus. Amino acid metabolism and carbohydrate metabolism were significant activities among the 16,093 and 49,652 genes that were annotated in the evolutionary genealogy of genes: Non-supervised Orthologous Groups (eggNOG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, respectively. In gluconeogenesis, red vinasse acid encodes 194 genes controlling the transporter protein systems of different sugars and has key enzyme genes that catalyze the conversion of intracellular sugars into glycolytic intermediates. In amino acid flavor formation, red vinasse acid contains 32 control genes for branched-chain aminotransferase (BCAT), 27 control genes for aromatic-amino-acid transaminase (ArAT), 60 control genes for keto acid invertase, 123 control genes for alcohol/aldehyde dehydrogenase, and 27 control genes for acetyl esterase, which have the basis for the formation of strong flavor substances from amino acids.

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.

Comparative transcriptomics discloses the regulatory impact of carbon/nitrogen fermentation on the biosynthesis of Monascus kaoliang pigments

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The synthesis of Monascus pigments (MPs) depends on many fermentation conditions.

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Carbon and nitrogen had important effect on the biosynthesis of MPs.

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Comparative transcriptomic provided a comprehensive interpretation of the links between primary and secondary metabolisms in MPs.

Carbon and nitrogen play a fundamental role in the production of Monascus pigments. However, their effects on pigment biosynthesis remain undetermined. In this study, we found that Monascus kaoliang produces pigments via liquid fermentation using glycerol and peptone as suitable carbon and nitrogen sources, respectively. Comparative transcriptomic profiling was performed using RNA sequencing. It indicated that the differentially expressed genes (DEGs) of carbon were enriched using amino acids and carbohydrates via the transport and metabolism pathways, respectively. DEGs of nitrogen were enriched only using general functional prediction pathways. These data provide a comprehensive interpretation of the linkage between primary and secondary metabolisms in M. kaoliang. Moreover, they provide insights into the effects of various substances involved in secondary metabolism.

Hepatoprotective Effects of Chitosan and Chitosan Nanoparticles against Biochemical, Genetic, and Histological Disorders Induced by the Toxicity of Emamectin Benzoate

Background

Emamectin benzoate (EMB) is a biopesticide which used in agriculture as an insecticide. It is easier to reach ecologically and affects human health. This study aims to evaluate the protective effect of chitosan and chitosan nanoparticles against EMB-induced hepatotoxicity.

Methods

Male mice were distributed into four groups: G1: the negative control, G2: EMB group (5 mg/kg diet), G3: EMB with Chitosan, (600 mg/kg diet), and G4: EMB with Chitosan nanoparticles (600 mg/kg diet). The experiment continues for 8 weeks, and the animals were sacrificed, and their organs were removed and immediately weighed after sacrifice. The liver was quickly removed and processed for histopathological and genetic studies.

Results

Emamectin benzoate (EMB) treatment induced oxidative stress by increased levels of Malondialdehyde (MDA), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) with inhibition of acetylcholinesterase (AChE), Superoxide dismutase (SOD) and Catalase (CAT) levels. EMB produced several histopathological changes in the liver. Relative expressions of studied genes elevated in the liver with increase in DNA damage. Co-treatment with chitosan and chitosan nanoparticles reduced EMB related liver toxicity that belong to biochemical, histopathological, gene expression, and DNA damage by increasing antioxidant capacity.

Conclusion

This study offers insight into the potential for Chitosan and chitosan nanoparticles as a novel natural material against the oxidative stress induced by EMB.

Bioactive Pigments of Monascus purpureus Attributed to Antioxidant, HMG-CoA Reductase Inhibition and Anti-atherogenic Functions

Monascus purpureus is known to produce pigment molecules. The pigments were extracted from M. purpureus fermented rice. In-vitro antioxidant effects of pigments were observed and presumed to alleviate oxidative stress related atherosclerosis effect in rats fed with high fat diet (HFD) for 14 weeks. The formation of lipid peroxide due to the oxidation of serum lipid was higher in rats fed with HFD. While, the feeding of fermented rice (groups III-V) significantly lowered the formation of lipid peroxide (27.1–51.7%) in serum of rats, indicated antioxidative effect of pigments. In addition, feeding of fermented rice lowered serum cholesterol and triacylglycerol by 44.82 and 45.30%, respectively. Whereas, LDL-cholesterol levels were decreased by 70.12% and HDL-cholesterol increased by 34.58%. The atherogenic indices (LDL/HDL and TC/HDL) were reduced by 77.80 and 61.05%, respectively, in rats fed with fermented rice. These data confirmed the anti-atherosclerotic effect of pigments. Further liver enzyme, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity was significantly inhibited up to 54%. The identification of statins, sterols and fatty acids in fermented rice revealed the HMG-CoA reductase inhibitory activity. This was confirmed by synthesis of lower levels of cholesterol and triacylglycerol in liver of rats fed with fermented rice. Accordingly antioxidant, inhibition of HMG-CoA reductase, anti-atherogenic functions of M. purpureus fermented rice is attributed to the collective effect of bioactive metabolites.

Isolation and characterization of ergosterol from Monascus anka for anti-lipid peroxidation properties

Unbalanced lipid peroxidation damages the human body, and is associated with the formation of tumors, infections, inflammations, autoimmune diseases, and cardiovascular and cerebrovascular diseases. However, food and drugs that contain anti-lipid peroxidation active substances, can help to protect against these negative health impacts. We observed lipid peroxidation inhibition in the metabolites of fermented Monascus anka, in media with Dendrobium nobile Lindl. The anti-lipid peroxidation ability of the extracts was strongest in ethyl acetate, so this was selected for further purifications. A crystal with strong antioxidant properties was obtained by column chromatography. Based on its spectroscopic analysis by Electron Bombardment Ion Source and Mass Spectrometry (EI-MS), ¹H-Nuclear Magnetic Resonance (¹H-NMR), and ¹³C-Nuclear Magnetic Resonance (¹³C-NMR), the isolated crystal was identified as ergosterol. The inhibition rates of the lipid peroxide due to the ergosterol were 57.42%, at 2μg/mL in vitro. Simultaneously, the survival rates of the damaged cells treated with 0.3mmol/L H₂O₂ were significantly improved with the ergosterol, up to 43.88% (200μg/mL) and 46.64% (400μg/mL), compared to 36.47% for the injured cells. The survival rate of the cells was 78.32% (400μg/mL), with ergosterol as a prevention. Cell injury can increase the level of intracellular ROS, but its levels in the damaged cells were reduced after the ergosterol treatments, and the reduction increased with the increasing concentrations. A 400μg/mL concentration resulted in the lowest fluorescence intensity; 33421.11 AU below the normal level. Ergosterol significantly reduced the ROS levels, to reduce the cell damage. Ergosterol from Monascus anka was thus found to have strong anti-lipid peroxidation and antioxidant capabilities, and the ability to protect and repair damaged cells. It may consequently serve as a potential natural antioxidant and will play an important role in human anti-lipid peroxide.

Doubled production of cordycepin analogs in cultured Cordyceps militaris by addition of Andrea droppings

Cordyceps sinensis is a traditional Chinese medicine with various biological activities. With its limited natural supply, cultured C. militaris has become the major alternative source, and the culture conditions may affect the chemical compositions. To improve the production of chemical ingredients, C. militaris was cultured with three different media, including rice only, rice plus 3% tea leaves, and rice plus 3% droppings of Andraca theae. The fractions of dried C. militaris cultured with rice were chromatographic separated to afford ten compounds: phenylalanine, dimerumic acid, nicotinic acid, tryptophan, N⁶-(2-hydroxyethyl)-adenosine, uracil, uridine, cordycepin, ergosterol, and mannitol. Of these, in the cultured medium of rice plus 3% Andraca droppings, the amount of one major compound cordycepin is about two folds than the highest reported data, and dimerumic acid and N⁶-(2-hydroxyethyl)-adenosine were isolated for the first time from this species.

Siderophores from the Entomopathogenic Fungus Beauveria bassiana

We report NMR- and MS-based structural characterizations of siderophores and related compounds from Beauveria bassiana (Balsamo-Crivelli) Vuillemin, including ten new chemical entities (2-4, 6-9, 11-12, and 15) and five known compounds, (1, 5, 10, 13, and 14). The siderophore mixture from ARSEF strain #2680 included two compounds in which N⁵-mevalonyl-N⁵-hydroxyornithine replaces both (2) or one (3) of the N⁵-anhydromevalonyl-N⁵-hydroxyornithine units of dimerumic acid (1). Mevalonolactone (14) was present as a degradation product of 2 and 3. ARSEF #2860 also produced compounds that have mannopyranose (5, 6) or 4-O-methyl-mannopyranose units (4, 7), two compounds (8, 9) that can be rationalized as 4-O-methyl-mannopyranosyl analogues of the esterifying acid moieties of metachelins A and B, respectively, and two probable decomposition products of 1, a nitro compound (11) and a formate (12). Beauverichelin A (15), a coprogen-type siderophore that represents the di-4-O-methyl-mannopyranosyl analogue of metachelin A, was detected in crude extracts of ARSEF #2860, but only in trace amounts. ARSEF strains #252 and #1955 yielded beauverichelin A in quantities that were sufficient for NMR analysis. Only the di- (1-7) and trihydroxamate (15) siderophores showed iron-binding activity in the CAS assay and, when ferrated, showed strong ESIMS signals consistent with 1:1 ligand/iron complexes.

Development of bioresources in Okinawa: understanding the multiple targeted actions of antioxidant phytochemicals

In research to develop healthy foods or preventive medicines from edible and medicinal herbs in Okinawa, we focused on the antioxidant activities of those bioresources. We first confirmed that the herbal antioxidant activities of such herbs increased upon ultraviolet irradiation treatment. This observation explains the high antioxidant activity of Okinawan vegetables, which grow under exposure to stronger ultraviolet light compared with those in other prefectures in Japan. Antidiabetic, hepatoprotective, cancer preventive, and cardioprotective actions were clarified using herbal extracts, and quercetin, chlorogenic acid, and gallic acid derivatives were isolated as antioxidant components from the herbs. Dimerumic acid was also isolated from the mold Monascus anka. All these antioxidants showed strong radical scavenging activities in vitro and beneficial effects in animal models. However, the concentrations of these compounds used in vivo seemed to be too low to have a physiologically important antioxidant effect based on their radical scavenging activities in vitro. Therefore, I performed a literature survey of antioxidant activities in vivo. Accumulating evidence has emerged that antioxidant phytochemicals show not only radical scavenging activities in vitro but also pleiotropic actions in vivo. The multitargeted, beneficial effects of antioxidant phytochemicals can be rationally explained using the xenohormesis concept, in which phytochemicals are the products of plant evolutionary adaptation to stress in plants, and their ability to induce a stress-adaptive response has been evolutionarily conserved in animals.

Structural Diversity and Biological Activities of the Cyclodipeptides from Fungi

Cyclodipeptides, called 2,5-diketopiperazines (2,5-DKPs), are obtained by the condensation of two amino acids. Fungi have been considered to be a rich source of novel and bioactive cyclodipeptides. This review highlights the occurrence, structures and biological activities of the fungal cyclodipeptides with the literature covered up to July 2017. A total of 635 fungal cyclodipeptides belonging to the groups of tryptophan-proline, tryptophan-tryptophan, tryptophan-Xaa, proline-Xaa, non-tryptophan-non-proline, and thio-analogs have been discussed and reviewed. They were mainly isolated from the genera of Aspergillus and Penicillium. More and more cyclodipeptides have been isolated from marine-derived and plant endophytic fungi. Some of them were screened to have cytotoxic, phytotoxic, antimicrobial, insecticidal, vasodilator, radical scavenging, antioxidant, brine shrimp lethal, antiviral, nematicidal, antituberculosis, and enzyme-inhibitory activities to show their potential applications in agriculture, medicinal, and food industry.

Monascus purpureus induced apoptosis on gastric cancer cell by scavenging mitochondrial reactive oxygen species

Monascus purpureus is a red dye derived from yeast rice and has been used as color additives for food in East Asia. Monascus purpureus consists of several bioactive components. Some of these components work as a radical scavenger, thus monascus purpureus would also eliminate reactive oxygen species. Cancer cells maintain the high level of reactive oxygen species than normal cell and are death by imbalance in pro-oxidant/antioxidant homeostasis. In this study, we investigated whether monascus purpureus induced cancer specific cell death by scavenging reactive oxygen species. Compared to normal cell, monascus purpureus had cancer specific cytotoxicity. Monascus purpureus and lovastatin, its component, scavenged free radicals caused by a xanthine/xanthine oxidase system, thus Monascus purpureus is likely to scavenge reactive oxygen species by a synergistic effect between lovastatin and other components. Monascus purpureus also decreased reactive oxygen species derived from mitochondria in cancer cells, and cellular apoptosis was induced via activation of caspase-9. Induction of apoptosis by reduction of reactive oxygen species generation decreased acid ceramidase, and this mechanism could be involved with increasing ceramide accumulation in cells.

2,5-diketopiperazines in food and beverages: Taste and bioactivity

2,5-Diketopiperazines (2,5-DKPs) have been found to occur in a wide range of food and beverages, and display an array of chemesthetic effects (bitter, astringent, metallic, and umami) that can contribute to the taste of a variety of foods. These smallest cyclic peptides also occur as natural products and have been found to display a variety of bioactivities from antibacterial, antifungal, to anthroprotective effects and have the potential to be used in the development of new functional foods. An overview of the synthesis of these small chiral molecules and their molecular properties is presented. The occurrence, taste, and bioactivity of all simple naturally occurring 2,5-DKPs to date have been reviewed and those found in food from yeasts, fungi, and bacteria that have been used in food preparation or contamination, as well as metabolites of sweeteners and antibiotics added to food are also reviewed.

Rice Koji Extract Enhances Lipid Metabolism through Proliferator-Activated Receptor Alpha (PPARα) Activation in Mouse Liver

Koji is made from grains fermented with Aspergillus oryzae and is essential for the production of many traditional Japanese foods. Many previous studies have shown that koji contributes to the improvement of dyslipidemia. However, little is known regarding the underlying mechanism of this effect. Furthermore, the compound contributing to the activation of lipid metabolism is unknown. We demonstrated that rice koji extract (RKE) induces the mRNA expression of peroxisome proliferator-activated receptor alpha (PPARα) target genes, which promotes lipid metabolism in murine hepatocytes. This effect was not observed in PPARα-KO hepatocytes. We also demonstrated that RKE contained linolenic acid (LIA), oleic acid (OA), and hydroxyoctadecadienoic acids (HODEs), which activate PPARα, using LC-MS analysis. Our findings suggest that RKE, containing LIA, OA, and HODEs, could be valuable in improving dyslipidemia via PPARα activation.

Dimerumic Acid and Deferricoprogen Activate Ak Mouse Strain Thymoma/Heme Oxygenase-1 Pathways and Prevent Apoptotic Cell Death in 6-Hydroxydopamine-Induced SH-SY5Y Cells

Parkinson's disease (PD) is a neurodegenerative disorder, which can be modeled using the neurotoxin 6-hydroxydopamine (6-OHDA) to generate oxidative stress. Here, we studied the effects of the antioxidants deferricoprogen (DFC) and dimerumic acid (DMA), produced by rice fermented with Monascus purpureus NTU 568, on 6-OHDA-induced apoptosis in SH-SY5Y cells and their potential protective mechanisms. DMA and DFC inhibited 6-OHDA-induced apoptosis and cellular reactive oxygen species (ROS) in SH-SY5Y human neuroblastoma cells. Molecular analysis demonstrated associated upregulation of the Ak mouse strain thymoma (Akt), heme oxygenase-1 (HO-1), and signal-regulated kinase (ERK) pathways along with inhibited phosphorylation of c-Jun N-terminal kinase (JNK) and p38 pathways and altered homodimeric glycoprotein, N-methyl-d-aspartate (NMDA) receptor, and immunoglobulin Fc receptor gene expression. These results suggested that the neuroprotection elicited by DMA and DFC against 6-OHDA-induced neurotoxicity was associated with the Akt, MAPK, and HO-1 pathways via regulating the gene expression of NMDA receptor, homodimeric glycoprotein, and immunoglobulin Fc receptor.

Neuroprotective effects of dimerumic acid and deferricoprogen from Monascus purpureus NTU 568-fermented rice against 6-hydroxydopamine-induced oxidative stress and apoptosis in differentiated pheochromocytoma PC-12 cells

Context Oxidative stress plays a key role in neurodegenerative disorders, including Parkinson's disease (PD). Rice fermented with Monascus purpureus Went (Monascaceae) NTU 568 (red mould rice) was found to contain antioxidants, including dimerumic acid (DMA) and deferricoprogen (DFC). Objective The effects of DMA and DFC on 6-hydroxydopamine (6-OHDA)-induced cytotoxicity and potential protective mechanisms in differentiated PC-12 pheochromocytoma cells were investigated. Materials and methods DMA (0-60 μM) or DFC (0-10 μM) was co-treated with 6-OHDA (200 μM, 24 h exposure) in differentiated PC-12 cells. Cell viability and intercellular reactive oxygen species (ROS) were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and 2',7'-dichlorofluorescein-diacetate (DCFH-DA) assays, respectively. Cell apoptosis was determined by DNA fragmentation analysis and propidium iodide staining by flow cytometry. Western blot analysis was used to measure the levels of cell protein expression. Results DMA and DFC significantly increased cell viability to 72% and 81% in 6-OHDA-induced differentiated PC-12 cell cultures, respectively. Furthermore, DMA and DFC reduced 6-OHDA-induced formation of extracellular and intercellular ROS by 25% and 20%, respectively, and decreased NADPH oxidase-2 expression in differentiated PC-12 cells. DMA and DFC inhibited 6-OHDA-induced apoptosis and decreased activation of caspase-3 via regulation of Bcl-2-associated X protein (Bax) and Bcl-2 protein expression in differentiated PC-12 cells. Conclusion DMA and DFC may protect against 6-OHDA toxicity by inhibiting ROS formation and apoptosis. These results showed that the metabolites from M. purpureus NTU 568 fermentation were potential therapeutic agents for PD induced by oxidative damage and should be encouraged for further research.

Biodegradable siderophores: survey on their production, chelating and complexing properties

The academic and industrial research on the interactions of complexing agents with the environment has received more attention for more than half a century ago and has always been concerned with the applications of chelating agents in the environment. In contrast, in recent years, an increasing scholarly interest has been demonstrated in the chemical and biological degradation of chelating agents. This is reflected by the increasing number of chelating agents-related publications between 1950 and middle of 2016. Consequently, the discovery of new green biodegradable chelating agents is of great importance and has an impact in the non-biodegradable chelating agent’s replacement with their green chemistry analogs. To acquire iron, many bacteria growing aerobically, including marine species, produce siderophores, which are low-molecular-weight compounds produced to facilitate acquisition of iron. To date and to the best of our knowledge, this is a concise and complete review article of the current and previous relevant studies conducted in the field of production, purification of siderophore compounds and their metal complexes, and their roles in biology and medicine.

The ameliorative effect of Monascus purpureus NTU 568-fermented rice extracts on 6-hydroxydopamine-induced neurotoxicity in SH-SY5Y cells and the rat model of Parkinson's disease

TheMonascus purpureusNTU 568-fermented rice extract contains antioxidants DMA and DFC, and it could reduce behavioral, neuronal, and biochemical characteristics in 6-OHDA-lesion rats.

Neurocytoprotective Effects of Aliphatic Hydroxamates from Lovastatin, a Secondary Metabolite from Monascus-Fermented Red Mold Rice, in 6-Hydroxydopamine (6-OHDA)-Treated Nerve Growth Factor (NGF)-Differentiated PC12 Cells

Lovastatin, a secondary metabolite isolated from Monascus-fermented red rice mold, has neuroprotective activity and permeates the blood-brain barrier. The aim of this study was to enhance the activity of lovastatin for potential use as a treatment for neuronal degeneration in Parkinson's disease. Six lovastatin-derived compounds were semisynthesized and screened for neurocytoprotective activity against 6-hydroxydopamine (6-OHDA)-induced toxicity in human neuroblastoma PC12 cells. Four compounds, designated as 3a, 3d, 3e, and 3f, significantly enhanced cell viability. In particular, compound 3f showed excellent neurocytoprotective activity (97.0 ± 2.7%). Annexin V-FITC and propidium iodide double staining and 4',6-diamidino-2-phenylindole staining indicated that compound 3f reduced 6-OHDA-induced apoptosis in PC12 cells. Compound 3f also reduced caspase-3, -8, and -9 activities, and intracellular calcium concentrations elevated by 6-OHDA in a concentration-dependent manner, without inhibiting reactive oxygen species generation. JC-1 staining indicated that compound 3f also stabilized mitochondrial membrane potential. Thus, compound 3f may be used as a neurocytoprotective agent. Future studies should investigate its potential application as a treatment for Parkinson's disease.

Filamentous fungi as a source of natural antioxidants

Ten species of filamentous fungi grown in submerged flask cultures were investigated for antioxidant capacity. Effective antioxidant activity was demonstrated in terms of β-carotene/linoleic acid bleaching, radical scavenging, reduction of metal ions and chelating abilities against ferrous ions. Different extraction methods affected antioxidant activities through their effect on biologically active compounds produced in fungal mycelia. The methanolic extract of each fungus was typically more effective in antioxidant properties. Phenolic content was established in the range of 0.44-9.33 mg/g, flavonoid contents were in the range of 0.02-3.90 mg/g and condensed tannin contents were in the range of 1.77-18.83 mg/g. Total phenol content of each extract was attributed to overall antioxidant capacity (r ⩾ 0.883-1.000). Submerged cultivation of Grifola frondosa, Monascus purpureus, Pleurotus spp., Lentinula edodes and Trametes versicolor proved to be an effective method for the production of natural antioxidants.

Metachelins, mannosylated and N-oxidized coprogen-type siderophores from Metarhizium robertsii

Under iron-depleted culture conditions, the entomopathogenic fungus Metarhizium robertsii (Bischoff, Humber, and Rehner) (= M. anisopliae) produces a complex of extracellular siderophores including novel O-glycosylated and N-oxidized coprogen-type compounds as well as the known fungal siderophores N(α)-dimethylcoprogen (NADC) and dimerumic acid (DA). Metachelin A (1), the most abundant component in the M. robertsii siderophore mixture, was characterized as a 1094 Da analogue of NADC that is O-glycosylated by β-mannose at both terminal hydroxyl groups and N-oxidized at the dimethylated α-nitrogen. The mixture also contained a 1078 Da analogue, metachelin B (2), which lacks the N-oxide modification. Also characterized were the aglycone of 1, i.e., the N-oxide of NADC (3), and the monomannoside of DA (6). N-Oxide and O-glycosyl substituents are unprecedented among microbial siderophores. At high ESIMS source energy and at room temperature in DMSO, 1 underwent Cope elimination, resulting in loss of the N(α)-dimethyl group and dehydration of the α-β bond. High-resolution ESIMS data confirmed that all tri- and dihydroxamate siderophores (1-6) complex with trivalent Fe, Al, and Ga. In a chrome azurol S assay, all of the M. robertsii siderophores showed iron-binding activity roughly equivalent to that of desferrioxamine B.

Suppression of dimerumic acid on hepatic fibrosis caused from carboxymethyl-lysine (CML) by attenuating oxidative stress depends on Nrf2 activation in hepatic stellate cells (HSCs)

Hyperglycemia facilitates the formation of advanced glycation end-products (AGEs) in type-2 diabetes. Evidence indicates that carboxymethyl-lysine (CML) is highly prevalent in diabetes, resulting in hepatic fibrosis. The current study was designed to evaluate the effects of dimerumic acid (DMA) identified from Monascus-fermented products on receptor for AGEs (RAGE) signal and hepatic stellate cells (HSCs) activation by CML treatment. We found that DMA (50 μM) eliminated collagen generation, mRNA expressions of α-smooth muscle actin (α-SMA), platelet-derived growth factor-β receptor (PDGF-βR), and procollagen 1a1 (proCol-1a1) in CML (100 μg/ml)-treated HSCs, and these effects were similar to allyl isothiocyanate (AITC; 50 μM). In addition, the suppression of α-SMA, PDGF-βR, proCol-1a1 by DMA were abolished while nuclear factor-erythroid 2-related factor 2 (Nrf2) silence in CML-treated HSCs. These findings suggested that DMA and AITC increased Nrf2 and glutamate-cysteine ligase (GCL) activities thereby inhibiting oxidative stress caused by CML and showing anti-fibrogentic effect in HSCs.

Dimerumic acid attenuates receptor for advanced glycation endproducts signal to inhibit inflammation and diabetes mediated by Nrf2 activation and promotes methylglyoxal metabolism into d-lactic acid

This study was designed to evaluate the effects of dimerumic acid (DMA) on receptor for advanced glycation endproducts (RAGE) signal activation and THP-1 monocyte inflammation treated with S100b, a specific ligand of RAGE. We found that DMA inhibited inflammatory cytokine production via upregulation of nuclear factor-erythroid 2-related factor 2 (Nrf2) and alleviated oxidative stress through attenuation of p47phox translocation to the membrane of S100b-treated THP-1 monocytes. We found that DMA activated Nrf2 mediated by the p38 kinase pathway in THP-1 monocytes. However, anti-inflammatory activity of DMA was attenuated by Nrf2 siRNA treatment. In an animal model, methylglyoxal (MG; 200mg/kg bw) was chosen to induce diabetes in Balb/C mice (6 weeks) in this work. The in vivo verification of anti-inflammation in peripheral blood mononuclear cells by DMA treatment was confirmed by tumor necrosis factor-α and interleukin-1β measurements. Oral glucose tolerance test, insulin tolerance test, hyperinsulinemia, and hyperglycemia were improved in MG-treated mice by DMA treatment and these effects were greater than those of silymarin and N-acetylcysteine. Furthermore, DMA increased hepatic glyoxalase mRNA and glutathione mediated by Nrf2 activation to metabolize MG into d-lactic acid, thereby reducing serum and hepatic AGE levels and suppressing inflammatory factor generation in MG-treated mice. However, DMA did not exert the antiglycation activity in MG-bovine serum albumin incubation. Taken together, the results indicate that DMA is a novel antioxidant and Nrf2 activator that lowers AGE levels and may prove to be an effective treatment for diabetes.

Ku70 and ku80 null mutants improve the gene targeting frequency in Monascus ruber M7

Normally, gene targeting by homologous recombination occurs rarely during a transformation process since non-homologous recombination is predominant in filamentous fungi. In our previous researches, the average gene replacement frequency (GRF) in Monascus ruber M7 was as low as 15 %. To develop a highly efficient gene targeting system for M. ruber M7, two M. ruber M7 null mutants of ku70 (MrΔku70) and ku80 (MrΔku80) were constructed which had no apparent defects in the development including vegetative growth, colony phenotype, microscopic morphology and spore yield compared with M. ruber M7. In addition, the production of some significant secondary metabolites such as pigments and citrinin had no differences between the two disruptants and the wild-type strain. Further results revealed that the GRFs of triA (encoding a putative acetyltransferase) were 42.2 % and 61.5 % in the MrΔku70 and MrΔku80 strains, respectively, while it was only about 20 % in M. ruber M7. Furthermore, GRFs of these two disruptants at other loci (the pigE, fmdS genes in MrΔku70 and the ku70 gene in MrΔku80) were investigated, and the results indicated that GRFs in the MrΔku70 strain and the MrΔku80 strain were doubled and tripled compared with that in M. ruber M7, respectively. Therefore, the ku70 and ku80 null mutants of M. ruber M7, especially the ku80-deleted strain, will be excellent hosts for efficient gene targeting.

Protective effect of deferricoprogen isolated from Monascus purpureus NTU 568 on citrinin-induced apoptosis in HEK-293 cells

Monascus species have traditionally been used in Asian food, with rice as their fermentation substrate. Red mold rice (RMR) contains citrinin, a nephrotoxic agent capable of exerting oxidative stress and cellular apoptosis. We investigated the components in RMR that could minimize the adverse effects of citrinin. Combining chemical separations and bioactivity assays, we identified an antioxidative component called deferricoprogen (DFC) in the fermented rice of Monascus purpureus NTU 568. The DFC structure was confirmed by nuclear magnetic resonance (NMR) and mass spectra analysis. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical-scavenging activity of DFC was similar to that of vitamin E. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay and flow cytometric analysis showed the effect of DFC and citrinin on cell viability and cell cycle. DFC was found to be protective against the cytotoxicity and cell death induced by citrinin on human embryonic kidney (HEK-293) cells. DFC also demonstrated anti-apoptotic property in preventing citrinin-induced apoptosis.

Biochemical aspects of red koji and tofuyo prepared using Monascus fungi

Red koji or red mold rice is prepared by growing a genus Monascus on steamed rice. For centuries, it has been used in Asia for the production of fermented foods including red rice wine and fermented tofu. Although red koji is an important source of various hydrolytic enzymes critical for food fermentation, information on the enzymatic properties in red koji has been limited. Hydrolytic enzymes produced by Monascus fungi may play important roles in ripening of tofuyo (Japanese fermented tofu) regarding the chemical and physical properties of the product. This review provides an introduction of red koji, its properties, and the application of hydrolytic enzymes, especially aspartic proteinases and carboxypeptidases from Monascus fungi. We also describe tofuyo and a novel fermented soybean protein food using a microbial action originating from red koji.

Monascus-fermented dioscorea enhances oxidative stress resistance via DAF-16/FOXO in Caenorhabditis elegans

BACKGROUND

Monascus-fermented products are mentioned in an ancient Chinese pharmacopoeia of medicinal food and herbs. Monascus-fermented products offer valuable therapeutic benefits and have been extensively used in East Asia for several centuries. Several biological activities of Monascus-fermented products were recently described, and the extract of Monascus-fermented products showed strong antioxidant activity of scavenging DPPH radicals. To evaluate whether Monascus-fermented dioscorea products have potential as nutritional supplements, Monascus-fermented dioscorea's modulation of oxidative-stress resistance and associated regulatory mechanisms in Caenorhabditis elegans were investigated.

PRINCIPAL FINDINGS

We examined oxidative stress resistance of the ethanol extract of red mold dioscorea (RMDE) in C. elegans, and found that RMDE-treated wild-type C. elegans showed an increased survival during juglone-induced oxidative stress compared to untreated controls, whereas the antioxidant phenotype was absent from a daf-16 mutant. In addition, the RMDE reduced the level of intracellular reactive oxygen species in C. elegans. Finally, the RMDE affected the subcellular distribution of the FOXO transcription factor, DAF-16, in C. elegans and induced the expression of the sod-3 antioxidative gene.

CONCLUSIONS

These findings suggest that the RMDE acts as an antioxidative stress agent and thus may have potential as a nutritional supplement. Further studies in C. elegans suggest that the antioxidant effect of RMDE is mediated via regulation of the DAF-16/FOXO-dependent pathway.

Ankaflavin and monascin regulate endothelial adhesion molecules and endothelial NO synthase (eNOS) expression induced by tumor necrosis factor-α (TNF-α) in human umbilical vein endothelial cells (HUVECs)

Previous studies have established that red mold rice can regulate blood pressure in spontaneously hypertensive rats (SHR) and that Monascus -fermented products, including monacolin K, ankaflavin (AF), and monascin (MS), can inhibit expression of adhesion factors such as E-selectin and endothelin-1 to prevent human acute monocytic leukemia cell line THP-1 monocytes from adhering to human aortic endothelial cells. However, it remains unknown whether AF and MS act directly on human umbilical endothelial cells (HUVECs) to enhance nitric oxide (NO) synthesis through the stimulation of endothelial NO synthase (eNOS) expression. To address this knowledge gap, this study investigated whether AF and MS directly regulate NO synthesis and attenuate adhesion factor expression induced by treatment with tumor necrosis factor-α (TNF-α) in HUVECs. The results revealed that both AF and MS (20 μM) treatments promoted increases in eNOS expression and decreases in vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and endothelin-1 mRNA and protein expression resulting from 12 h of TNF-α treatment. These effects are attributed to the ability of AF and MS to inhibit extracellular signal-regulated protein kinase (ERK) phosphorylation and nuclear factor κB (NF-κB) translocation from the cytoplasm into the nucleus, thereby exerting antihypertensive activity.

A Review and Update of Red Yeast Rice

Dyslipidemia is a growing concern causing significant morbidity and mortality. High cholesterol levels increase the risk of individuals developing heart disease, stroke, and other disease states. Dietary modification is the initial approach for treatment, but many patients require statins (3-hydroxy-3-methylglutaryl co-enzyme A reductase inhibitors) to reduce cardiovascular risk. Unfortunately, a number of patients cannot tolerate statins, leading to practitioners searching for alternative regimens. One alternative that has been extensively studied is red yeast rice ( Monascus purpureus), a dietary supplement. In patients with dyslipidemia, red yeast rice was efficacious and safe for short-term use (<16 weeks). Red yeast rice has also been studied head to head with statins and was shown to be noninferior in reducing cholesterol levels and cardiovascular risk. Because of the positive clinical effects seen in dyslipidemia, researchers have begun to study its use in other disease states.

Reduction of serum lipids by the intake of the extract of garlic fermented with Monascus pilosus: a randomized, double-blind, placebo-controlled clinical trial

BACKGROUND & AIMS

A dietary supplement containing garlic fermented with Monascus pilosus (MGFE) may be useful to decrease the lipid concentrations in serum without serious adverse effects. The aim of the study was to assess whether MGFE decreases serum lipid contents in volunteers with mild hyperlipidemia in a randomized, double-blind, placebo-controlled, parallel-group trial.

METHODS

Healthy subjects (n = 55) with serum triglyceride concentrations of 120-200mg/dL were randomly assigned to take either MGFE or placebo capsules for 12 wk.

RESULTS

A borderline, but not significant effect, to decrease triglyceride concentrations in serum (approximately 15% reduction at maximum, P = 0.062, in time × treatment interaction effect) was observed by the MGFE intake for 12 wk. The decreased reading exhibited a significant difference at wk-8 between the MGFE and placebo groups (unpaired t test, P = 0.007). The total cholesterol (P = 0.003) and LDL cholesterol (P = 0.001) contents in the serum and the LDL/HDL ratio (P < 0.001) were significant in time × treatment interaction effects by the MGFE intake. However, no alteration in the body fat percentage and abdominal circumference was observed.

CONCLUSIONS

The intake of MGFE decreased triglyceride and cholesterol in serum with no appreciable adverse effects in normal to mildly hyperlipidemic individuals, suggesting that it may be effective to improve and prevent the metabolic syndrome. This clinical trial was registered with Clinicaltrials.gov as NCT00938249.