microbial fermentation
Dotaz
Zobrazit nápovědu
Microbial transglutaminase (MTG) is an enzyme widely used in the food industry because it creates cross-links between proteins, enhancing the texture and stability of food products. Its unique properties make it a valuable tool for modifying the functional characteristics of proteins, significantly impacting the quality and innovation of food products. In this study, response surface methodology was employed to optimize the fermentation conditions for microbial transglutaminase production by the strain Streptoverticillium cinnamoneum KKP 1658. The effects of nitrogen dose, cultivation time, and initial pH on the activity of the produced transglutaminase were investigated. The significance of the examined factors was determined as follows: cultivation time > nitrogen dose > pH. The interaction between nitrogen dose and cultivation time was found to be crucial, having the second most significant impact on transglutaminase activity. Optimal conditions were identified as 48 h of cultivation with a 2% nitrogen source dose and an initial medium pH of approximately 6.0. Under these conditions, transglutaminase activity ranged from 4.5 to 5.5 U/mL. The results of this study demonstrated that response surface methodology is a promising approach for optimizing microbial transglutaminase production. Future applications of transglutaminase include the development of modern food products with improved texture and nutritional value, as well as its potential use in regenerative medicine for creating biomaterials and tissue scaffolds. This topic is particularly important and timely as it addresses the growing demand for innovative and sustainable solutions in the food and biomedical industries, contributing to an improved quality of life.
In screening biocontrol strains with broad-spectrum and high-efficiency herbicidal activities, a strain with strong pathogenicity, HY-021, was isolated from the leaves of Rumex acetosa, which was identified as Botrytis fabiopsis based on morphology and molecular biology. The herbicidal activities of the fermentation filtrate of strain HY-021 against nine weeds, including Chenopodium album L., Elsholtzia densa Benth., Malva verticillata L. var. Crispa, Polygonum lapathifolium L., Amaranthus retroflexus L., Avena fatua L., Thlaspi arvense L., Polygonum aviculare L., and Galium spurium L., were determined in vitro and in vivo. The results showed that the pathogenicity of strain HY-021 to the different weeds in vitro was as follows: E. densa > A. retroflexus > P. aviculare > P. lapathifolium > M. verticillata > T. arvense > G. spurium > A. fatua > C. album. Seven days after inoculation with the HY-021 strain, the incidences in nine weeds were in the range of 32.9-87.23%, and the disease index values of the nine weeds were 41.73-94.57%. The pathogenic effects from high to low were A. retroflexus > E. densa > A. fatua > G. spurium > C. album > M. verticillata > T. arvense > P. aviculare > P. lapathifolium. The crop safety test showed that the biocontrol strain HY-021 was safe to V. faba, P. sativum, H. vulgare, and T. aestivum, but had a slight effect on B. napus. Scanning electron microscopy showed that the mycelium of strain HY-021 invaded the tissue through the stomata of C. album leaves, parasitized and reproduced in the tissue, and gradually destroyed the tissue. The results of this study provide a basis for the development and utilization of new and efficient microbial source herbicides.
- MeSH
- biologická kontrola škůdců * metody MeSH
- biologická ochrana * MeSH
- Botrytis * izolace a purifikace fyziologie genetika patogenita MeSH
- herbicidy metabolismus farmakologie MeSH
- kontrola plevele * metody MeSH
- listy rostlin mikrobiologie MeSH
- nemoci rostlin * mikrobiologie prevence a kontrola MeSH
- plevel * mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Čína MeSH
Apple replant disease (ARD) is a significant factor restricting the healthy development of the apple industry. Biological control is an important and sustainable method for mitigating ARD. In this study, a strain of Paenibacillus polymyxa GRY-11 was isolated and screened from the rhizosphere soil of healthy apple trees in old apple orchards in Shandong Province, China, and the effects of strain GRY-11 on soil microbial community and ARD were studied. The result showed that P. polymyxa GRY-11 could effectively inhibit the growth of the main pathogenic fungi that caused ARD, and the inhibition rates of the strain against Fusarium moniliforme, Fusarium proliferatum, Fusarium solani, and Fusarium oxysporum were 80.00%, 71.60%, 75.00%, and 70.00%, respectively. In addition, the fermentation supernatant played an active role in suppressing the growth of pathogenic fungi. The results of the pot experiment showed that the bacterial fertilizer of the GRY-11 promoted the growth of Malus hupehensis seedlings, improved the activity of protective enzymes in plant roots, enhanced the soil enzyme content, and optimized the soil microbial environment. In general, the GRY-11 can be used as an effective microbial preparation to alleviate ARD. Our study offers novel perspectives for the prevention of ARD.
- MeSH
- antibióza MeSH
- biologická kontrola škůdců * MeSH
- biologická ochrana * MeSH
- Fusarium růst a vývoj MeSH
- houby růst a vývoj MeSH
- kořeny rostlin mikrobiologie MeSH
- Malus * mikrobiologie růst a vývoj MeSH
- nemoci rostlin * mikrobiologie prevence a kontrola MeSH
- Paenibacillus polymyxa * izolace a purifikace fyziologie genetika klasifikace MeSH
- půdní mikrobiologie MeSH
- rhizosféra MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Čína MeSH
Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Burkholderia cenocepacia are considered emerging pathogens classified as a public health problem due to extensive antimicrobial resistance. Therefore, the discovery of new therapeutic strategies has become crucial. This study aimed to evaluate the antimicrobial activity of gallic acid and methyl gallate against non-fermenting bacteria. The study included five clinical isolates of Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Burkholderia cenocepacia. The minimum inhibitory concentrations of gallic acid and methyl gallate were determined by the broth microdilution method. Growth curves, metabolic activity, and biofilm formation of each bacterial strain in the presence or absence of phenolic compounds were performed. Finally, the therapeutic efficacy of the compounds was evaluated using an in vivo model. Gallic acid and methyl gallate showed antibacterial activity against bacterial strains in a concentration range of 64 to 256 μg/mL, both compounds reduced bacterial growth and metabolic activity of the strains, even at subinhibitory concentrations. Only, methyl gallate exhibited activity to inhibit the formation of bacterial biofilms. Moreover, gallic acid and methyl gallate increased larval survival by up to 60% compared to 30% survival of untreated larvae in a bacterial infection model in Galleria mellonella. Our results highlight the potential of gallic acid and methyl gallate as therapeutic alternatives for infections by emerging non-fermentative bacteria.
Allodiploid hybrid species, Aspergillus latus, belonging to section Nidulantes, is a hybrid of A. spinulosporus and an unknown species closely related to A. quadrilineatus and A. sublatus. This hybrid has often been misidentified as the species in section Nidulantes, such as A. nidulans, A. spinulosporus, A. sublatus, or other cryptic species. Aspergillus latus has not been reported in Japan as well as Asia so far. In this study, we screened 23 clinical strains identified as A. spinulosporus isolated in Japan from 2012 to 2023 and found seven A. latus strains. To characterize the A. latus strains, we conducted comprehensive phenotyping including morphological observation, whole genome sequences, and phylogenetic analysis based on calmodulin (CaM) gene. In addition, we conducted antifungal susceptibility testing for A. latus strains. As a result, the morphological characters of A. latus were more similar to those of A. spinulosporus compared to A. sublatus. However, the ascospore of A. latus differed from that of A. spinulosporus. Phylogenetic analysis revealed that different CaM alleles from the same isolate clustered separately with A. spinulosporus and A. sublatus, consistent with its hybrid origin. Furthermore, A. latus strains showed reduced susceptibility to caspofungin and amphotericin B compared to A. spinulosporus, while they were susceptible to azoles. Our results suggest that A. latus has been a causative pathogen of aspergillosis in Japan since 2013.
- MeSH
- antifungální látky farmakologie MeSH
- Aspergillus * genetika klasifikace izolace a purifikace účinky léků MeSH
- aspergilóza * mikrobiologie epidemiologie MeSH
- fylogeneze MeSH
- kalmodulin genetika MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- sekvenování celého genomu MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Japonsko MeSH
Super- and low-shedding phenomena have been observed in genetically homogeneous hosts infected by a single bacterial strain. To decipher the mechanisms underlying these phenotypes, we conducted an experiment with chicks infected with Salmonella Enteritidis in a non-sterile isolator, which prevents bacterial transmission between animals while allowing the development of the gut microbiota. We investigated the impact of four commensal bacteria called Mix4, inoculated at hatching, on chicken systemic immune response and intestinal microbiota composition and functions, before and after Salmonella infection. Our results revealed that these phenotypes were not linked to changes in cell invasion capacity of bacteria during infection. Mix4 inoculation had both short- and long-term effects on immune response and microbiota and promoted the low-shedder phenotype. Kinetic analysis revealed that Mix4 activated immune response from day 4, which modified the microbiota on day 6. This change promotes a more fermentative microbiota, using the aromatic compounds degradation pathway, which inhibited Salmonella colonization by day 11 and beyond. In contrast, control animals exhibited a delayed TNF-driven pro-inflammatory response and developed a microbiota using anaerobic respiration, which facilitates Salmonella colonization and growth. This strategy offers promising opportunities to strengthen the barrier effect against Salmonella and possibly other pathogens.
- MeSH
- Bacteria * klasifikace genetika izolace a purifikace MeSH
- kur domácí * mikrobiologie imunologie MeSH
- nemoci drůbeže * mikrobiologie imunologie prevence a kontrola MeSH
- Salmonella enteritidis * imunologie růst a vývoj MeSH
- salmonelová infekce u zvířat * mikrobiologie imunologie prevence a kontrola MeSH
- střevní mikroflóra * MeSH
- symbióza MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Monascus pigments having yellow, orange, and red colors are widely studied for their potential beneficial properties. Many different biological activities have been reported regarding Monascus pigments and their derivatives, but the usual method is to test complex extracts from the mycelium of the fungus or from a fungus-fermented substrate. However, this review is mainly concerned with the biological activities of purified Monascus pigments. Both yellow (ankaflavin, monascin) and red (rubropunctamine, monascorubramine) Monascus pigments are proven antioxidants if used in concentrations of 10 μg/mL or higher. Antimicrobial activity against Gram-positive and Gram-negative bacteria and fungi has been observed with all Monascus pigments. However, the best antimicrobials are red Monascus pigments, and their amino acid derivatives (l-cysteine derivatives have MIC 4 μg/mL against Enterococcus faecalis). Yellow monaphilones and orange monaphilols seem to have the highest anti-inflammatory activity (IC50 1.7 μM of monaphilol D) and, together with red Monascus pigment derivatives, have mild antiobesity and antidiabetic activities. Further, monascin and ankaflavin in daily doses of 0.5 and 0.08 mg, respectively, lowered serum blood levels of low-density lipoprotein cholesterol complexes in rats on a high-fat diet. Orange Monascus pigments, rubropunctatin and monaphilols A and C, exhibit cytotoxic and antitumor activities (IC50 8-10 μM).
- MeSH
- antibakteriální látky farmakologie chemie izolace a purifikace MeSH
- antiflogistika farmakologie chemie izolace a purifikace MeSH
- antiinfekční látky farmakologie chemie izolace a purifikace MeSH
- antioxidancia farmakologie chemie izolace a purifikace MeSH
- biologické pigmenty * farmakologie chemie izolace a purifikace MeSH
- flaviny farmakologie chemie MeSH
- grampozitivní bakterie účinky léků MeSH
- heterocyklické sloučeniny tricyklické MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- molekulární struktura MeSH
- Monascus * chemie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Daunomycin is a chemotherapeutic agent widely used for the treatment of leukemia, but its toxicity toward healthy dividing cells limits its clinical use and its production by fermentation. Herein, we describe the development of a specialized cultivation medium for daunomycin production, including a shift to oil rather than sugar as the primary carbon source. This achieved an almost threefold increase in daunomycin yields, reaching 5.5-6.0 g/L. Daunomycin produced in the oil-based medium was predominantly found in the solid sediment, whereas that produced in the sugar-based medium was mostly soluble. The oil-based medium thus induces an autonomous daunomycin-resistance mechanism involving biogenic nanoparticle formation. The characterization of the nanoparticles confirmed the incorporation of iron and daunomycin, indicating that this approach has the potential to mitigate cytotoxicity while improving yields. The presence of proteins associated with iron homeostasis and oxidative stress responses revealed the ability of the production strain to adapt to high iron concentrations. Our findings provide insight into the mechanisms of biogenic nanoparticle formation and the optimization of cultivation processes. Further investigation will help to refine microbial production systems for daunomycin and also broaden the application of similar strategies for the synthesis of other therapeutically important compounds.
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Exclusive enteral nutrition (EEN) is an effective treatment for active Crohn's disease (CD). This study explored the immunostimulatory potential of a cell-free fecal filtrate and related this with changes in the fecal microbiota and metabolites in children with active CD undertaking treatment with EEN. METHODS: Production of tumor necrosis factor α (TNFα) from peripheral blood mononuclear cells was measured following their stimulation with cell-free fecal slurries from children with CD, before, during, and at completion of EEN. The metabolomic profile of the feces used was quantified using proton nuclear magnetic resonance and their microbiota composition with 16S ribosomal RNA sequencing. RESULTS: Following treatment with EEN, 8 (72%) of 11 patients demonstrated a reduction in fecal calprotectin (FC) >50% and were subsequently labeled FC responders. In this subgroup, TNFα production from peripheral blood mononuclear cells was reduced during EEN (P = .008) and reached levels like healthy control subjects. In parallel to these changes, the fecal concentrations of acetate, butyrate, propionate, choline, and uracil significantly decreased in FC responders, and p-cresol significantly increased. At EEN completion, TNFα production from peripheral blood mononuclear cells was positively correlated with butyrate (rho = 0.70; P = .016). Microbiota structure (β diversity) was influenced by EEN treatment, and a total of 28 microbial taxa changed significantly in fecal calprotectin responders. At EEN completion, TNFα production positively correlated with the abundance of fiber fermenters from Lachnospiraceae_UCG-004 and Faecalibacterium prausnitzii and negatively with Hungatella and Eisenbergiella tayi. CONCLUSIONS: This study offers proof-of concept data to suggest that the efficacy of EEN may result from modulation of diet-dependent microbes and their products that cause inflammation in patients with CD.
- MeSH
- Crohnova nemoc * terapie mikrobiologie imunologie MeSH
- dítě MeSH
- enterální výživa * metody MeSH
- feces * mikrobiologie chemie MeSH
- leukocytární L1-antigenní komplex * analýza MeSH
- leukocyty mononukleární imunologie metabolismus MeSH
- lidé MeSH
- mladiství MeSH
- střevní mikroflóra * MeSH
- TNF-alfa * metabolismus MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Ectoine is an important natural secondary metabolite in halophilic microorganisms. It protects cells against environmental stressors, such as salinity, freezing, drying, and high temperatures. Ectoine is widely used in medical, cosmetic, and other industries. Due to the commercial market demand of ectoine, halophilic microorganisms are the primary method for producing ectoine, which is produced using the industrial fermentation process "bacterial milking." The method has some limitations, such as the high salt concentration fermentation, which is highly corrosive to the equipment, and this also increases the difficulty of downstream purification and causes high production costs. The ectoine synthesis gene cluster has been successfully heterologously expressed in industrial microorganisms, and the yield of ectoine was significantly increased and the cost was reduced. This review aims to summarize and update microbial production of ectoine using different microorganisms, environments, and metabolic engineering and fermentation strategies and provides important reference for the development and application of ectoine.
- MeSH
- aminokyseliny diaminové * metabolismus MeSH
- biotechnologie MeSH
- fermentace MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH