Unveiling the potential of red koji polysaccharides: biosynthesis, extraction, and multifaceted biological activities.

Red koji polysaccharides, derived from the fermentation of Monascus, have been recognized for their health-enhancing properties. This article reviews their structural characteristics, biosynthesis pathways, and biological activities. It emphasizes the need for sustainable practices in fermentation and the optimization of extraction methods for scalable production. The significance of exploring the molecular mechanisms involved in their biosynthesis is also highlighted to enhance yield and efficiency. Research indicates that red koji polysaccharides possess diverse biological functions, beneficial for pharmaceutical applications due to their health benefits and minimal toxicity. The review points out the necessity for more detailed studies on key enzymes and genes in biosynthesis to improve production methods. It also identifies the current challenges in production scalability and extraction efficiency. Furthermore, while these polysaccharides show potential in pharmaceuticals, their clinical efficacy and mechanism of action in human subjects require further investigation. The review briefly explores potential structural modifications to improve their biological activities. The review concludes that red koji polysaccharides hold significant untapped potential, particularly in drug formulation. Future research should focus on overcoming current production and application challenges, including conducting clinical trials to validate their efficacy and exploring structural modifications for enhanced therapeutic benefits. This comprehensive understanding of red koji polysaccharides paves the way for their expanded application in the pharmaceutical industry. © 2024 Society of Chemical Industry.

Linoleic acid functions as a quorum-sensing molecule in Monascus purpureus-Saccharomyces cerevisiae co-culture.

When Monascus purpureus was co-cultured with Saccharomyces cerevisiae, we noted significant changes in the secondary metabolism and morphological development of Monascus. In yeast co-culture, although the pH was not different from that of a control, the Monascus mycelial biomass increased during fermentation, and the Monacolin K yield was significantly enhanced (up to 58.87% higher). However, pigment production did not increase. Co-culture with S. cerevisiae significantly increased the expression levels of genes related to Monacolin K production (mokA-mokI), especially mokE, mokF, and mokG. Linoleic acid, that has been implicated in playing a regulating role in the secondary metabolism and morphology of Monascus, was hypothesized to be the effector. Linoleic acid was detected in the co-culture, and its levels changed during fermentation. Addition of linoleic acid increased Monacolin K production and caused similar morphological changes in Monascus spores and mycelia. Exogenous linoleic acid also significantly upregulated the transcription levels of all nine genes involved in the biosynthesis of Monacolin K (up to 69.50% higher), consistent with the enhanced Monacolin K yield. Taken together, our results showed the effect of S. cerevisiae co-culture on M. purpureus and suggested linoleic acid as a specific quorum-sensing molecule in Saccharomyces-Monascus co-culture.

The regulatory functions of oxylipins in fungi: A review.

Quorum sensing (QS) is a communication mechanism between microorganisms originally found in bacteria. In recent years, an important QS mechanism has been discovered in the field of fungi, namely, the lipoxygenase compound oxylipin of arachidonic acid acts as a QS molecule in life cycle control, particularly in the sexual and asexual development of fungi. However, the role of oxylipins in mediating eukaryotic communication has not been previously described. In this paper, we review the regulatory role of oxylipins and the underlying mechanisms and discuss the potential for application in major fungi. The role of oxylipin as a fungal quorum-sensing molecule is the main focus of the review. Besides, the quorum regulation of fungal morphological transformation, biofilm formation, virulence factors, secondary metabolism, infection, symbiosis, and other physiological behaviors are discussed. Moreover, future prospectives and applications are elaborated as well.

A Novel Microbial Consortia Catalysis Strategy for the Production of Hydroxytyrosol from Tyrosine.

Hydroxytyrosol, a valuable plant-derived phenolic compound, is increasingly produced from microbial fermentation. However, the promiscuity of the key enzyme HpaBC, the two-component flavin-dependent monooxygenase from Escherichia coli, often leads to low yields. To address this limitation, we developed a novel strategy utilizing microbial consortia catalysis for hydroxytyrosol production. We designed a biosynthetic pathway using tyrosine as the substrate and selected enzymes and overexpressing glutamate dehydrogenase GdhA to realize the cofactor cycling by coupling reactions catalyzed by the transaminase and the reductase. Additionally, the biosynthetic pathway was divided into two parts and performed by separate E. coli strains. Furthermore, we optimized the inoculation time, strain ratio, and pH to maximize the hydroxytyrosol yield. Glycerol and ascorbic acid were added to the co-culture, resulting in a 92% increase in hydroxytyrosol yield. Using this approach, the production of 9.2 mM hydroxytyrosol was achieved from 10 mM tyrosine. This study presents a practical approach for the microbial production of hydroxytyrosol that can be promoted to produce other value-added compounds.

Coking-Resistant Polyethylene Upcycling Modulated by Zeolite Micropore Diffusion.

Although the mass production of synthetic plastics has transformed human lives, it has resulted in waste accumulation on the earth. Here, we report a low-temperature conversion of polyethylene into olefins. By mixing the polyethylene feed with rationally designed ZSM-5 zeolite nanosheets at 280 °C in flowing hydrogen as a carrier gas, light hydrocarbons (C1-C7) were produced with a yield of up to 74.6%, where 83.9% of these products were C3-C6 olefins with almost undetectable coke formation. The reaction proceeds in multiple steps, including polyethylene melting, flowing to access the zeolite surface, cracking on the zeolite surface, formation of intermediates to diffuse into the zeolite micropores, and cracking into small molecules in the zeolite micropores. The ZSM-5 zeolite nanosheets kinetically matched the cascade cracking steps on the zeolite external surface and within micropores by boosting the intermediate diffusion. This feature efficiently suppressed the intermediate accumulation on the zeolite surface to minimize coke formation. In addition, we found that hydrogen participation in the cracking process could hinder the formation of polycyclic species within zeolite micropores, which also contributes to the rapid molecule diffusion. The coking-resistant polyethylene upcycling process at a low temperature not only overturns the general viewpoint for facile coke formation in the catalytic cracking over the zeolites but also demonstrates how the polyethylene-based plastics can be upcycled to valuable chemicals. In addition to the model polyethylene, the reaction system worked efficiently for the depolymerization of multiple practically used polyethylene-rich plastics, enabling an industrially and economically viable path for dealing with plastic wastes.

Zeolite Fixed Metal Nanoparticles: New Perspective in Catalysis.

ConspectusLoading metal nanoparticles on the surface of solid supports has emerged as an efficient route for the preparation of heterogeneous catalysts. Notably, most of these supported metal nanoparticles still have shortcomings such as dissatisfactory activity and low product selectivity in catalysis. In addition, these metal nanoparticles also suffer from deactivation because of nanoparticle sintering, leaching, and coke formation under harsh conditions. The fixation of metal nanoparticles within zeolite crystals should have advantages of high activities for metal nanoparticles and excellent shape selectivity for zeolite micropores as well as extraordinary stability of metal nanoparticles immobilized with a stable zeolite framework, which is a good solution for the shortcomings of supported metal nanoparticles.Materials with metal nanostructures within the zeolite crystals are normally denoted as metal@zeolite, where the metal nanoparticles with diameters similar to those of industrial catalysts are usually larger than the micropore size. These metal nanoparticles are enveloped with the zeolite rigid framework to prevent migration under harsh reaction conditions, which is described as a fixed structure. The zeolite micropores allow the diffusion of reactants to the metal nanoparticles. As a result, metal@zeolite catalysts combine the features of both metal nanoparticles (high activity) and zeolites (shape selectivity and thermal stability), compared with the supported metal nanoparticles.In this Account, we describe how the zeolite micropore and metal nanoparticle synergistically work to improve the catalytic performance by the preparation of a variety of metal@zeolite catalysts. Multiple functions of zeolites with respect to the metal nanoparticles are highlighted, including control of the reactant/product diffusion in the micropores, the adjustment of reactant adsorption on the metal nanoparticles, and sieving the reactants and products with zeolite micropores. Furthermore, by optimizing the wettability of the zeolite external surface, the zeolite crystals could form a nanoreactor to efficiently enrich the crucial intermediates, thus boosting the performance in low-temperature methane oxidation. Also, the microporous confinement weakens the adsorption of C1 intermediates on the metal sites, accelerating the C-C coupling to improve C2 oxygenate productivity in syngas conversion. In particular, the zeolite framework efficiently stabilizes the metal nanoparticles against sintering and leaching to give durable catalysts. Clearly, this strategy not only guides the rational design of efficient heterogeneous catalysts for potential applications in a variety of industrial chemical reactions but also accelerates the fundamental understanding of the catalytic mechanisms by providing new model catalysts.

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.

Studies on the biosynthetic pathways of melanin in Auricularia auricula.

Melanin is a natural pigment ubiquitously present in living organisms, including bacteria, fungi, plants, and animals. Melanin produced by the edible mushroom Auricularia auricula has a remarkable potential for resource development. Several A. auricula strains planted across China were collected and analyzed for mycelial growth rate and colony red, green, blue (RGB) value for color block. Further, the effects of various nutrients on melanin formation, including different carbon and nitrogen sources were evaluated to optimize the medium for submerged fermentation. The pathways involved in the biosynthesis of melanin in A. auricula were investigated using an enzyme inhibitor assay and intermediate determination. In addition, the functional activity of purified A. auricula melanin was assessed. The highest melanin yield (1.797 g/L) was displayed by strain AU-3 in medium I. A. auricula melanin was composed of eumelanin, pheomelanin, and 1,8-dihydroxynaphthalene melanin, and the biosynthetic pathways involved were Raper-Mason and 1,8-dihydroxynaphthalene melanin pathway. In addition, melanin purified from A. auricula exhibited substantial antioxidant, antibacterial, and antitumor activities.

Histamine Causes Pyroptosis of Liver by Regulating Gut-Liver Axis in Mice.

Huangjiu usually caused rapid-drunkenness and components such as ß-benzyl ethanol (ß-be), isopentanol (Iso), histamine (His), and phenethylamine (PEA) have been reported linked with intoxication. However, the destructive effect of these components on gut microbiota and liver is unclear. In this study, we found oral treatment of these components, especially His, stimulated the level of oxidative stress and inflammatory cytokines in liver and serum of mice. The gut microbiota community was changed and the level of lipopolysaccharide (LPS) increased significantly. Additionally, cellular pyroptosis pathway has been assessed and correlation analysis revealed a possible relationship between gut microbiota and liver pyroptosis. We speculated oral His treatment caused the reprogramming of gut microbiota metabolism, and increased LPS modulated the gut-liver interaction, resulting in liver pyroptosis, which might cause health risks. This study provided a theoretical basis for the effect of Huangjiu, facilitating the development of therapeutic and preventive strategies for related inflammatory disorders.

Transcriptome analysis revealing molecular mechanisms of enhanced pigment yield by succinic acid and fluconazole.

This study aimed to elucidate the molecular mechanisms through which succinic acid and fluconazole stimulate Monascus pigment biosynthesis under liquid fermentation conditions. The pigment yield was significantly improved by adding 0.35 g·L-1 succinic acid or 1.5 g·L-1 fluconazole. Transcriptome sequencing and RT-qPCR confirmation were performed to reveal transcriptome changes. The results indicated that the addition of succinic acid significantly decreased mRNA expression of genes involved in fatty acid biosynthesis while increasing expression of genes involved in pyruvate metabolism. Fluconazole significantly down-regulated transcripts involved in branched-chain amino acid metabolism, fatty acid metabolism, glycolysis/gluconeogenesis, and pyruvate metabolism, as well as the generation of acetyl-CoA for pigment biosynthesis. On the other hand, nitrogen metabolism and lysine degradation pathways were significantly enriched, which could stimulate the generation of acetyl-CoA. Therefore, the mechanism for enhancing pigment yield may be attributed to the competitive regulation of metabolic pathways toward acetyl-CoA biosynthesis. Additionally, up-regulation of some different key genes in the presence of fluconazole or succinic acid was involved in improving pigment production. This study deepens the theoretical understanding for enhancing pigment biosynthesis and provides a few potential approaches for improving pigment yield.

Regulated synthesis and metabolism of Monascus pigments in a unique environment.

Microbial fermentation in extreme environments is the focus of research, which provides new insights for the production and application of Monascus pigments. In this paper, the regulation of Monascus pigments metabolism by optimizing the conditions, such as osmotic pressure, high sugar stress, light, extreme temperature, high-water content, low-frequency magnetic field and ultrasonics, is reviewed and summarized in four parts: the mycelium growth of Monascus spp., metabolic pathways, gene expression and composition characteristics of Monascus pigments. The relationship between mycelial morphology, gene expression and pigments production during fermentation under unique environments is discussed. Based on the changes in metabolic pathways and composition characteristics, the regulatory mechanism of Monascus pigments under unique conditions is proposed. Moreover, the fermentation strategy and application prospects of Monascus pigments in unique environments are also discussed. This work will provide a theoretical basis and practical guidance for the optimized production of Monascus pigments.

Effects of Huangjiu, Baijiu and Red Wine Combined With High-Fat Diet on Glucose and Lipid Metabolism: Aggravate or Alleviate?

AIM: To compare effects on certain health indices in rodents of different doses of alcoholic beverages, huangjiu (Chinese yellow wine), red wine and baijiu (Chinese liquor) combined with high-fat diet (HFD) and the pure HFD. METHODS: A total of 80 rats were randomly divided into eight groups and treated with (a) basal diet (3.5 kcal/g); (b) HFD (19.5% w/w lard, 4.5 kcal/g) and (c) HFD with low or high doses of separate alcoholic beverages (2.5 and 5 g/kg ethanol, respectively) for 28 weeks. RESULTS: Chronic drinking when combined with HFD was associated with reduced body weight, fat accumulation and serum TNF-α level, serum TG, TC and LDL-C levels, and improved glucose tolerance (OGTT) and insulin sensitivity (ITT), hepatic enzymes; elevated levels or activities of the antioxidant enzymes like superoxide dismutase, catalase and glutathione reductase, reduced the content of lipid peroxidation productions such as malondialdehyde, in comparison with the pure HFD intake. In addition, compared with HFD, drinking plus HFD improved microbiota dysbiosis, down-regulated the ratio of Firmicutes/Bacteroidetes and promoted the growth of some probiotics including Prevotellaceae_UCG-001 and norank_f__Bacteroidales_S24-7_group. CONCLUSION: Overall, the three beverages showed different impacts on indicators but red wine showed the most 'beneficial' effects. Of course, higher ethanol dosages can be expected to cause overall negative health effects, and harms of high fat intake can be prevented by healthier diet.

Structural Insights for the Stronger Ability of Shrimp Ferritin to Coordinate with Heavy Metal Ions as Compared to Human H-Chain Ferritin.

Although apoferritin has been widely utilized as a new class of natural protein nanovehicles for encapsulation and delivery of nutraceuticals, its ability to remove metal heavy ions has yet to be explored. In this study, for the first time, we demonstrated that the ferritin from kuruma prawns (Marsupenaeus japonicus), named MjF, has a pronouncedly larger ability to resist denaturation induced by Cd2+ and Hg2+ as compared to its analogue, human H-chain ferritin (HuHF), despite the fact that these two proteins share a high similarity in protein structure. Treatment of HuHF with Cd2+ or Hg2+ at a metal ion/protein shell ratio of 100/1 resulted in marked protein aggregation, while the MjF solution was kept constantly clear upon treatment with Cd2+ and Hg2+ at different protein shell/metal ion ratios (50/1, 100/1, 250/1, 500/1, 1000/1, and 2500/1). Structural comparison analyses in conjunction with the newly solved crystal structure of the complex of MjF plus Cd2+ or Hg2+ revealed that cysteine (Cys) is a major residue responsible for such binding, and that the large difference in the ability to resist denaturation induced by these two heavy metal ions between MjF and HuHF is mainly derived from the different positions of Cys residues in these two proteins; namely, Cys residues in HuHF are located on the outer surface, while Cys residues from MjF are buried within the protein shell. All of these findings raise the high possibility that prawn ferritin, as a food-derived protein, could be developed into a novel bio-template to remove heavy metal ions from contaminated food systems.

Insulin Receptor Substrate 1 Is Involved in the Phycocyanin-Mediated Antineoplastic Function of Non-Small Cell Lung Cancer Cells.

Phycocyanin, derived from marine algae, is known to have noteworthy antineoplastic properties. However, the underlying mechanism involved in phycocyanin-mediated anti-growth function on non-small cell lung cancer (NSCLC) cells is still ambiguous. Here, we investigated the mechanism of action of phycocyanin on H1299, A549, and LTEP-a2 cells. According to the results obtained, insulin receptor substrate 1 (IRS-1) expression was reduced by phycocyanin. Cell phenotype tests showed that siRNA knockdown of IRS-1 expression significantly inhibited the growth, migration, colony formation, but promoted the apoptosis of NSCLC cells. Meanwhile, phycocyanin and IRS-1 siRNA treatment both reduced the PI3K-AKT activities in NSCLC cells. Moreover, overexpression of IRS-1 accelerated the proliferation, colony formation, and migration rate of H1299, A549, and LTEP-a2 cells, which was contradicting to the knockdown results. Overall, this study uncovered a regulatory mechanism by which phycocyanin inhibited the growth of NSCLC cells via IRS-1/AKT pathway, laying the foundation for the potential target treatment of NSCLC.

Promotion of monacolin K production in Monascus extractive fermentation: the variation in fungal morphology and in the expression levels of biosynthetic gene clusters.

BACKGROUND: Monacolin K, an important secondary metabolite of Monascus, possesses a cholesterol-lowering effect and is widely used in the manufacture of antihypertensive drugs. In the present study, we constructed an extractive fermentation system by adding non-ionic surfactant and acquired a high monacolin K yield. The mechanism was determined by examining both cell morphology and the transcription levels of the related mokA-I genes in the monacolin K biosynthetic gene cluster. RESULTS: The monacolin K yield was effectively increased to 539.59 mg L-1 during extraction, which was an increase of 386.16% compared to that in the control group fermentation. The non-ionic surfactant showed good biocompatibility with Monascus. Electron scanning microscopy revealed alterations in the morphology of Monascus. The loosened mycelial structure and increased number of cell surface wrinkles were found to be related to the increased cell-membrane permeability and extracellular accumulation of monacolin K. Gene expression levels were measured via a quantitative reverse transciptase-polymerase chain reaction. By contrast, in the control group, mokA, mokB, mokC, mokD and mokF showed higher-level and longer-term expression in the extractive fermentation group, whereas mokE and mokG did not present a similar trend. The expression levels of mokH and mokI, encoding a transcription factor and efflux pump, respectively, were also higher than the control levels. CONCLUSION: The addition of a non-ionic surfactant to Monascus fermentation effectively increases the yield of monacolin K by transforming the fungus morphology and promoting the expression of monacolin K biosynthesis genes. © 2021 Society of Chemical Industry.

The structure and stability analysis of the pea seed legumin glycosylated by oligochitosan.

BACKGROUND: The functionality of pea proteins is relatively weak relative to that of soybean proteins, which limits the application of pea proteins in food and nutritional applications. Glycosylation is a promising approach to influence the protein structure and in turn change the functional properties of pea proteins. RESULTS: In this study, the effect of transglutaminase-induced oligochitosan glycosylation on the structural and functional properties of pea seed legumin was studied. Different oligochitosan-modified legumin complexes (OLCs) were prepared by applying different molar ratios of legumin to oligochitosan (1:1 to 1:4) induced by transglutaminase (10 U g-1 protein). Results of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), glucosamine, and free amino analysis showed that the legumin could be covalently bonded with the oligochitosan and were influenced by the applying dose of the oligochitosan. Infrared spectroscopy, fluorescence, and scanning electron microscopy analysis indicated that the structure of the different OLC samples could be changed to different extents. Moreover, although the emulsifying activity decreased, the emulsification stability, thermal stability, and in vitro digestive stability of the OLCs were remarkably improved relative to that of the untreated legumin. CONCLUSION: Oligochitosan glycosylation could change the structure of the legumin and consequently improve its emulsification stability, thermal stability, and in vitro digestive stability. This study will facilitate the legumin functionalization by the glycosylation approach to fabricate protein-oligochitosan complex for potential food and nutritional applications. © 2020 Society of Chemical Industry.

Molecular mechanism of the response of Zygosaccharomyces rouxii to D-fructose stress by the glutathione metabolism pathway.

Zygosaccharomyces rouxii produces high levels of 4-hydroxy-2,5-dimethyl-3(2H)-furanone in YPD medium supplemented with 120 g/L D-fructose and 180 g/L NaCl after 5 d. D-fructose has a stress effect on Z. rouxii, and GSH-Px is a main enzyme involved in the defense of Z. rouxii against oxygen stress according to our previous report. In order to further explore the molecular mechanism of the glutathione metabolism pathway in Z. rouxii in response to D-fructose stress, changes in the expression of genes and proteins involved in the synthesis of glutathione precursor amino acids and enzymes were observed. In addition, changes in the intermediates related to glutathione synthesis in Z. rouxii were reported. The results indicated that some gene-encoding enzymes involved in the glutamate, cysteine and glycine biosynthesis pathways and key genes involved in glutathione synthesis were upregulated. The expression levels of other genes, except SHMT, were consistent with the qRT-PCR results. The contents of γ-glutamylcysteine and glutathione amide in the D-fructose group were higher than those in the control group. In the D-fructose stress groups, the metabolic flux towards glutathione synthesis was increased. These results might provide more in-depth and detailed theoretical support for the oxidative stress defense mechanism of Z. rouxii under D-fructose stress.

Investigation of the mycelial morphology of Monascus and the expression of pigment biosynthetic genes in high-salt-stress fermentation.

Extreme environments, for example high-salt-stress condition, that can induce secondary metabolite biosynthesis in fungi are a promising and effective strategy for producing natural Monascus pigments used as food colourants and nutraceutical supplements. In this study, the relationship between the mycelial morphology and expression of pigment biosynthetic genes in high-salt-stress fermentation (HSF) with Monascus ruber CGMCC 10910 was investigated. The Monascus fungus grew well under HSF conditions with 35 g/l NaCl, and the intracellular yellow pigment yield in HSF was 40% higher than that in conventional batch fermentation (CBF). Moreover, the mycelial morphology was maintained in a better state, with a hyphal diameter of 5-6 µm in HSF, indicating good biocatalytic activity for pigment synthesis. The rate of the relative content of intracellular orange pigments to yellow pigments (O/Y) significantly (p < 0.05) changed, and the extracellular yellow pigments were transformed into each other, indicating that the pigment biosynthesis pathway was changed to promote yellow pigment accumulation in HSF. The pigment biosynthesis genes MpPKS5, MpFasB2, mppE, mppD and mppB were significantly (p < 0.05) up-regulated by approximately 58.4-106.1%, whereas the regulatory genes mppR1 and mppR2 were significantly (p < 0.05) down-regulated by approximately 23.2% and 59.0% in HSF. Notably, the mppE gene was highly correlated with (r > 0.95, p < 0.05) hyphal diameter. These findings indicated that the cultivation of the Monascus fungus under high-salt-stress conditions was beneficial for pigment biosynthesis by controlling the mycelial morphology to regulate gene expression. This study first described the relationship between the mycelial morphology and expression of pigment biosynthetic genes in Monascus during fermentation. KEY POINTS: • High-salt-stress fermentation (HSF) was first performed to improve Monascus pigment yield. • Pigment biosynthesis was enhanced by maintaining the mycelial morphology in an improved state in HSF. • Gene expression was up-/downregulated to promote yellow pigment accumulation in HSF. • The mycelial morphology was highly related to the expression of pigment biosynthetic genes in HSF.

Overexpression of global regulator LaeA increases secondary metabolite production in Monascus purpureus.

Monascus is a filamentous fungus that produces several secondary metabolites. Here, we investigated the effects of the global regulator LaeA on the synthesis of pigments and monacolin K in Monascus purpureus with spectrophotometer and HPLC methods. The LaeA gene was isolated from M. purpureus M1 to create an overexpression construct. An LaeA-overexpressing strain L3 was with 48.6% higher monacolin K production than the M1 strain. The L3 strain also produced higher Monascus pigments than the M1 strain. SEM showed that LaeA overexpression resulted in altered mycelial morphology. Compared with the M1 strain, the L3 strain expressed higher levels of monacolin K synthesis-related genes mokA, mokB, mokE, and mokH. Overall, these results suggest that LaeA plays a role in regulating the production of secondary metabolites and mycelial growth in Monascus. This study provides important insights into the mechanisms underlying the effects of the LaeA gene on the secondary metabolites of M. purpureus.

Essential Oil and Juice from Bergamot and Sweet Orange Improve Acne Vulgaris Caused by Excessive Androgen Secretion.

Acne vulgaris is one of the most common chronic inflammatory skin diseases. Bergamot and sweet orange are rich in nutritional and functional components, which exhibit antioxidant, anti-inflammatory, and antiapoptotic effect. The aim of this study was to evaluate the potential effect of bergamot and sweet orange (juice and essential oil) on acne vulgaris caused by excessive secretion of androgen. Eighty male golden hamsters were randomly divided into 10 groups and received low or high dose of bergamot and sweet orange juice and essential oil, physiological saline, and positive drugs for four weeks, respectively. Results showed that all interventions could improve acne vulgaris by reducing the growth rate of sebaceous gland spots, inhibiting TG accumulation, decreasing the release of inflammatory cytokines (notably reducing IL-1α levels), promoting apoptosis in the sebaceous gland, and decreasing the ratio of T/E2. Among them, bergamot and orange essential oil may have better effects (dose dependent) on alleviating acne vulgaris than the corresponding juice. In view of the large population of acne patients and the widespread use of sweet orange and bergamot, this study is likely to exert an extensive and far-reaching influence.