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FEMS Microbiology Letters Jan 2024Monascus pigments (MPs) are a kind of natural ingredient fermented by Monascus spp., which contains three types of pigments: red, orange, and yellow ones. Monascus...
Monascus pigments (MPs) are a kind of natural ingredient fermented by Monascus spp., which contains three types of pigments: red, orange, and yellow ones. Monascus yellow pigments have a restricted yield and cannot meet industrial application. The method and mechanism of CaCl2 improving yellow pigments production by liquid fermentation of Monascus purpureus M8 were studied in order to overcome the low yield of yellow pigments produced by liquid fermentation. Changes in physiological and biochemical indicators explained the effects of CaCl2 on the production of Monascus yellow pigments from solid fermentation. The intracellular yellow pigments, orange pigments, and red pigments increased by 156.08%, 43.76%, and 42.73%, respectively, with 60 g/l CaCl2 addition to culture medium. The amount of red and orange pigments reduced, while the proportion of yellow pigments increased and the relative peak area of intracellular yellow pigments accounted for a dominant 98.2%, according to thin layer chromatography and high performance liquid chromatography analyses. Furthermore, the influence of CaCl2 extended to the modulation of pigments synthesis-related gene expression in M8 strain. This modulation led to a pronounced upregulation in the expression of the yellow pigments synthesis-related gene, mppE, signifying a pivotal role played by CaCl2 in orchestrating the intricate machinery behind yellow pigments biosynthesis.
Topics: Fermentation; Monascus; Calcium Chloride; Pigments, Biological
PubMed: 38378945
DOI: 10.1093/femsle/fnae012 -
Journal of Bioscience and Bioengineering May 2024The unique cellar fermentation process of Chinese strong-flavor Baijiu is the reason for its characteristic cellar aroma flavor. The types, abundance, community...
The unique cellar fermentation process of Chinese strong-flavor Baijiu is the reason for its characteristic cellar aroma flavor. The types, abundance, community structure and metabolic activity of microorganisms in the pit mud directly affect the microbial balance in the white spirit production environment, promoting the formation of typical aromas and influencing the quality of CFSB. During the production process, the production of off-flavor in the cellar may occur. The aim of this study is to elucidate the differences in microbiota and flavor between normal pit mud and abnormal pit mud (pit mud with off-flavor). A total of 46 major volatile compounds were identified, and 24 bacterial genera and 21 fungal genera were screened. The esters, acids, and alcohols in the abnormal pit mud were lower than those in the normal pit mud, while the aldehydes were higher. 3-Methyl indole, which has been proven to be responsible for the muddy and musty flavors, was detected in both types of pit mud, and for the first time, high levels of 4-methylanisole was detected in the pit mud. The microbial composition of the two types of pit mud showed significant differences in the bacterial genera of Sporosarcina, Lactobacillus, Garciella, Anaerosalibacter, Lentimicrobium, HN-HF0106, Petrimonas, Clostridium_sensu_stricto_12 and Bacillus, and the fungal genera of Millerozyma, Penicillium, Mortierella, Monascus, Saccharomyces, Issatchenkia, Pithoascus, Pseudallescheria, and Wickerhamomyces. Additionally, we speculate that Sporosarcina is the predominant bacterial genus responsible for the imbalance of microbiota in pit mud.
Topics: Odorants; Alcoholic Beverages; Bacteria; Fermentation; Microbiota
PubMed: 38369397
DOI: 10.1016/j.jbiosc.2023.12.009 -
Journal of Basic Microbiology Apr 2024In eukaryotes, methylation of histone H3 at lysine 4 (H3K4me) catalyzed by the complex of proteins associated with Set1 (COMPASS) is crucial for the transcriptional...
In eukaryotes, methylation of histone H3 at lysine 4 (H3K4me) catalyzed by the complex of proteins associated with Set1 (COMPASS) is crucial for the transcriptional regulation of genes and the development of organisms. In Monascus, the functions of COMPASS in establishing H3K4me remain unclear. This study first identified the conserved COMPASS core subunits MpSet1 and MpSwd3 in Monascus purpureus and confirmed their roles in establishing H3K4me2/3. Loss of MpSet1 and MpSwd3 resulted in slower growth and development and inhibited the formation of cleistothecia, ascospores, and conidia. The loss of these core subunits also decreased the production of extracellular and intracellular Monascus pigments (MPs) by 94.2%, 93.5%, 82.7%, and 82.5%, respectively. In addition, RNA high-throughput sequencing and quantitative real-time polymerase chain reaction (qRT-PCR) showed that the loss of MpSet1 and MpSwd3 altered the expression of 2646 and 2659 genes, respectively, and repressed the transcription of MPs synthesis-related genes. In addition, the ΔMpset1 and ΔMpswd3 strains demonstrated increased sensitivity to cell wall stress with the downregulation of chitin synthase-coding genes. These results indicated that the COMPASS core subunits MpSet1 and MpSwd3 help establish H3K4me2/3 for growth and development, spore formation, and pigment synthesis in Monascus. These core subunits also assist in maintaining cell wall integrity.
Topics: Monascus; Fermentation; Pigments, Biological
PubMed: 38362934
DOI: 10.1002/jobm.202300686 -
Journal of the Science of Food and... May 2024Ergothioneine (EGT) is a high-value food functional factor that cannot be synthesized by humans and other vertebrates, and the low yield limits its application.
BACKGROUND
Ergothioneine (EGT) is a high-value food functional factor that cannot be synthesized by humans and other vertebrates, and the low yield limits its application.
RESULTS
In this study, the optimal fermentation temperature, fermentation time, initial pH, inoculum age, and inoculation ratio on EGT biosynthesis of Rhodotorula mucilaginosa DL-X01 were optimized. In addition, the effects of three key precursor substances - histidine, methionine, and cysteine - on fungal EGT synthesis were verified. The optimal conditions were further obtained by response surface optimization. The EGT yield of R. mucilaginosa DL-X01 under optimal fermentation conditions reached 64.48 ± 2.30 mg L at shake flask fermentation level. Finally, the yield was increased to 339.08 ± 3.31 mg L (intracellular) by fed-batch fermentation in a 5 L bioreactor.
CONCLUSION
To the best of our knowledge, this is the highest EGT yield ever reported in non-recombinant strains. The fermentation strategy described in this study will promote the efficient biosynthesis of EGT in red yeast and its sustainable production in the food industry. © 2024 Society of Chemical Industry.
Topics: Humans; Animals; Ergothioneine; Rhodotorula; Antioxidants; Histidine; Fermentation; Monascus
PubMed: 38353320
DOI: 10.1002/jsfa.13287 -
Food & Function Feb 2024In our previous study, a polyphenol-utilization targeted quinoa product was developed solid-state fermentation with . In this study, we investigated the...
In our previous study, a polyphenol-utilization targeted quinoa product was developed solid-state fermentation with . In this study, we investigated the polyphenol-related novel functions of the fermented product further. Compared with unfermented quinoa, fermented quinoa alleviated the trapping effect of the macromolecules, especially in the colonic fermentation stage, resulting in enhanced polyphenol bioaccessibility. , , , , and might contribute to polyphenol liberation and metabolism in fermented quinoa. Additionally, fermented quinoa polyphenols presented an efficient anti-obesity effect by enhancing hepatic antioxidant enzyme activities, suppressing fatty acid synthesis, accelerating fatty acid oxidation, and improving bile acid synthesis. Moreover, fermented quinoa polyphenol supplementation alleviated gut microbiota disorder induced by a high-fat diet, resulting in a decreased ratio of /, and increased relative abundances of and . The obtained results suggested that the principal anti-obesity effect of fermented quinoa polyphenols might act through the AMPK/PPAR/CPT-1 pathway. In conclusion, solid-state fermentation effectively enhanced the bioaccessibility of quinoa, and the fermented quinoa polyphenols showed considerable anti-obesity effect. Our findings provide new perspectives for the development of dietary polyphenol-based satiety-enhancing functional foods.
Topics: Polyphenols; Chenopodium quinoa; Monascus; Fermentation; Gastrointestinal Microbiome; Fatty Acids
PubMed: 38317482
DOI: 10.1039/d3fo04555b -
PeerJ 2024Fungi can have important beneficial and detrimental effects on animals, yet our understanding of the diversity and function of most bee-associated fungi is poor. Over 2...
Fungi can have important beneficial and detrimental effects on animals, yet our understanding of the diversity and function of most bee-associated fungi is poor. Over 2 million bumblebee colonies are traded globally every year, but the presence and transport of viable fungi within them is unknown. Here, we explored whether any culturable fungi could be isolated from commercial bumblebee nests. We collected samples of various substrates from within 14 bumblebee colonies, including the honey, honey cup wall, egg cup wall, and frass then placed them on agar and recorded any growth. Fungal morphotypes were then subcultured and their ITS region sequenced for identification. Overall, we cultured 11 fungal species from the various nest substrates. These included both pathogenic and non-pathogenic fungi, such as sp., sp., and sp. Our results provide the first insights into the diversity of viable fungal communities in commercial bumblebee nests. Further research is needed to determine if these fungi are unique to commercial colonies or prevalent in wild bumblebee nests, and crucially to determine the ecological and evolutionary implications of these fungi in host colonies.
Topics: Bees; Animals; Aspergillus; Penicillium; Agar
PubMed: 38313023
DOI: 10.7717/peerj.16713 -
Journal of the Science of Food and... Jul 2024Baijiu brewing is a complex and multifaceted multimicrobial co-fermentation process, in which various microorganisms interact to form an interdependent micro-ecosystem,...
BACKGROUND
Baijiu brewing is a complex and multifaceted multimicrobial co-fermentation process, in which various microorganisms interact to form an interdependent micro-ecosystem, subsequently influencing metabolic activities and compound production. Among these microorganisms, Bacillus, an important bacterial genus in the liquor brewing process, remains unclear in its role in shaping the brewing microbial community and its functional metabolism.
RESULTS
A baijiu fermentation system was constructed using B. subtilis JP1 isolated from native jiupei (grain mixture) combined with daqu (a saccharifying agent) and huangshui (a fermentation byproduct). Based on high-throughput amplicon sequencing analysis, it was evident that B. subtilis JP1 significantly influences bacterial microbial diversity and fungal community structure in baijiu fermentation. Of these, Aspergillus and Monascus emerge as the most markedly altered microbial genera in the jiupei community. Based on co-occurrence networks and bidirectional orthogonal partial least squares discriminant analysis models, it was demonstrated that the addition of B. subtilis JP1 intensified microbial interactions in jiupei fermentation, consequently enhancing the production of volatile flavor compounds such as heptanoic acid, butyl hexanoate and 3-methylthiopropanol in jiupei.
CONCLUSION
B. subtilis JP1 significantly alters the microbial community structure of jiupei, enhancing aroma formation during fermentation. These findings will contribute to a broader application in solid-state fermentation. © 2024 Society of Chemical Industry.
Topics: Bacillus subtilis; Fermentation; Microbiota; Volatile Organic Compounds; Metabolome; Bacteria; Alcoholic Beverages; Aspergillus; Flavoring Agents; Fungi; Monascus
PubMed: 38296914
DOI: 10.1002/jsfa.13345 -
Journal of the Science of Food and... Jul 2024Red koji polysaccharides, derived from the fermentation of Monascus, have been recognized for their health-enhancing properties. This article reviews their structural... (Review)
Review
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.
Topics: Humans; Polysaccharides; Monascus; Animals; Fermentation
PubMed: 38294276
DOI: 10.1002/jsfa.13318 -
Food Chemistry: X Mar 2024The Xiecun Huangjiu (XCHJ), an exemplary representation of North Huangjiu, exhibits a distinct and invigorating aroma predominantly formed during its aging period. In...
The Xiecun Huangjiu (XCHJ), an exemplary representation of North Huangjiu, exhibits a distinct and invigorating aroma predominantly formed during its aging period. In this study, we observed dynamic changes in 16 key aroma compounds by gas chromatography-mass spectrometry (GC-MS) during the aging of XCHJ, with compounds such as phenethylalcohol, isoamylalcohol, benzaldehyde, and ethylbenzoate initially increasing and then decreasing. Ultra-Performance Liquid Chromatography (UPLC) detected nineteen amino acids, with total content ranging from 1901.45 to 3764.45 mg/L. High-throughput sequencing indicated that and et al. were abundant in aged XCHJ. Totally, 4 bacteria and 8 fungi exhibited strong associations with aroma compounds production. Physicochemical properties were primarily interacted with , , , , and . Furthermore, co-occurrence network analysis highlighted significant interactions between , , , and amino acids. These findings provide valuable insights for the regulation of aroma in aged XCHJ.
PubMed: 38292673
DOI: 10.1016/j.fochx.2024.101132 -
International Journal of Food... Mar 2024Knowledge of the metabolism of functional enzymes is the key to accelerate the transformation and utilization of raw materials during high temperature Daqu (HTD)...
Knowledge of the metabolism of functional enzymes is the key to accelerate the transformation and utilization of raw materials during high temperature Daqu (HTD) manufacturing. However, the metabolic contribution of raw materials-wheat is always neglected. In this research, the relationship between the metabolism of wheat and microorganisms was investigated using physicochemical and sequencing analysis method. Results showed that the process of Daqu generation was divided into three stages based on temperature. In the early stage, a positive correlation was found between Monascus, Rhizopus and glucoamylase metabolism (r > 0.8, p < 0.05). Meanwhile, the glucoamylase metabolism in wheat occupied 63.8 % of the total matrix at the day 4. In the middle to later stages, the wheat metabolism of proteases, α-amylases and lipases in gradually reached their peak. Additionally, Lactobacillus and α-amylases presented a positive correlation (r > 0.7, p < 0.05), and the α-amylases metabolism in wheat occupied 22.18 % of the total matrix during the same time period. More importantly, the changes of enzyme activity metabolic pathway in wheat and microorganism were reflected by respiratory entropy (RQ). Overall, these results guide the choice of substrate during Daqu production.
Topics: Fermentation; Bacteria; Triticum; Glucan 1,4-alpha-Glucosidase; Temperature; Microbiota; alpha-Amylases; Alcoholic Beverages
PubMed: 38281434
DOI: 10.1016/j.ijfoodmicro.2024.110589