RESUMEN

AIMS: To develop antifungal lactic acid bacteria (LAB) and investigate their antifungal mechanisms against Aspergillus flavus in aflatoxin (AF) production. METHODS AND RESULTS: We isolated 179 LABs from cereal-based fermentation starters and investigated their antifungal mechanism against A. flavus through liquid chromatography-mass spectrometry and co-culture analysis techniques. Of the 179 isolates, antifungal activity was identified in Pediococcus pentosaceus, Lactobacillus crustorum, and Weissella paramesenteroides. These LABs reduced AF concentration by (i) inhibiting mycelial growth, (ii) binding AF to the cell wall, and (iii) producing antifungal compounds. Species-specific activities were also observed, with P. pentosaceus inhibiting AF production and W. paramesenteroides showing AF B1 binding activity. In addition, crucial extracellular metabolites for selecting antifungal LAB were involved in the 2',3'-cAMP-adenosine and nucleoside pathways. CONCLUSIONS: This study demonstrates that P. pentosaceus, L. crustorum, and W. paramesenteroides are key LAB strains with distinct antifungal mechanisms against A. flavus, suggesting their potential as biological agents to reduce AF in food materials.

Asunto(s)

Antifúngicos , Aspergillus flavus , Técnicas de Cocultivo , Lactobacillales , Metabolómica , Aspergillus flavus/metabolismo , Aspergillus flavus/crecimiento & desarrollo , Aspergillus flavus/efectos de los fármacos , Antifúngicos/farmacología , Antifúngicos/metabolismo , Lactobacillales/metabolismo , Lactobacillales/crecimiento & desarrollo , Fermentación , Aflatoxinas/biosíntesis , Grano Comestible/microbiología , Pediococcus pentosaceus/metabolismo , Antibiosis , Microbiología de Alimentos

RESUMEN

This study developed a method for quantifying eight short-chain fatty acids (SCFAs) in mouse fecal samples using solid-phase microextraction (SPME) coupled with triple quadrupole gas chromatography tandem mass spectrometry. Furthermore, significant factors affecting SCFA analysis, including SPME fiber selection, pH, salting-out agent, and sample collection time, were investigated. Contrary to previous studies, we found that the CAR/PDMS fiber had the highest extraction efficiency for all SCFAs. The optimal extraction efficiency was observed at pH 2.0, particularly for low-molecular-weight SCFAs. NaH2PO4 showed a more effective extraction efficiency than NaCl, owing to its pH stability and less interference with the solvent matrix. Additionally, our results showed that the SCFA concentration increased over collection time. The composition ratio of the eight SCFAs was maintained for up to 24 h; thus, we concluded that samples should be collected within four hours to obtain reliable results. Our findings may improve laboratory methods for SCFA extraction and mouse fecal sample analysis.

RESUMEN

Gellan gum (GG) is an anionic polysaccharide used as an additive in the food industry. However, the effect of GG on gut microbiota regulation and nonalcoholic fatty liver disease (NAFLD) has not yet been investigated. In vitro fermentation experiments have demonstrated that GG promoted the growth of probiotic strains such as Lactiplantibacillus rhamnosus and Bifidobacterium bifidum, producing metabolites beneficial to gut health. In mice, GG reduced hepatic triglyceride content, serum biomarkers, and body fat mass and weight gain induced by a high fat diet. Additionally, GG regulated the gut microbiota including Desulfovibrionales, Deferribacterales, Bacteroidales, and Lactobacillales at the order level and also promoted short-chain fatty acid production. Moreover, GG improved the expression of proteins related to hepatic inflammation and lipid metabolism. Taken together, GG ameliorated NAFLD, possibly by acting on the gut-liver axis via improving the gut health, indicating its potential as a food supplement and/or prebiotic against NAFLD.

Asunto(s)

Microbioma Gastrointestinal , Enfermedad del Hígado Graso no Alcohólico , Animales , Biomarcadores/metabolismo , Dieta Alta en Grasa/efectos adversos , Ácidos Grasos Volátiles/metabolismo , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/genética , Polisacáridos Bacterianos/farmacología , Triglicéridos/metabolismo

RESUMEN

Doenjang is a traditional Korean fermented soybean-based food that is now produced industrially as traditional Doenjang and modernized Doenjang, depending on the conditions of the manufacturing process. In this study, the effect of the production process on Doenjang metabolites was analyzed using untargeted capillary electrophoresis time-of-flight mass spectrometry (CE-TOF/MS). Of the 247 metabolites detected in 19 traditional and three modernized Doenjang samples, the level of 55 metabolites were significantly different between the two production groups. The S-plot of the orthogonal projection to latent structures-discriminant analysis (OPLS-DA) revealed that nine compounds (tryptamine, 2-phenylethylamine, citrulline, gamma-aminobutyric acid, putrescine, tyramine, 2-aminoisobutyric acid, stachydrine, and N5-ethylglutamine) were highly distributed in the traditional group, and six compounds (arginine, citric acid, choline, cytidine, hypoxanthine, and glucaric acid) were considered distinguishable metabolites of the modernized group. Microbial community analysis indicated that the levels of these metabolites were significantly altered by the presence of Bacillus spp., Enterococcus faecium, Tetragenococcus halophilus, Aspergillus oryzae, Penicillium spp., and Saccharomyces cerevisiae. These findings will give better understanding of the influence of the manufacturing process on Doenjang production in terms of both microbial activity and metabolite profiles.

Asunto(s)

Alimentos de Soja , Fermentación , Microbiología de Alimentos , Metabolómica , Alimentos de Soja/análisis , Glycine max/química

RESUMEN

Signaling lymphocytic activating molecule family member 1 (SLAMF1 or CD150) is a cell surface glycoprotein expressed on various immune populations, regulating cell-cell interactions, activation, differentiation, and inflammatory responses and has been suggested as a potential target for inflammatory diseases. Signaling is believed to be mediated by high-affinity homophilic interactions; the recombinant soluble form of SLAMF1 has optimal activity in the range of 20 µg/mL. This contradicts with a rather weak homo-dimerization binding constant (KD) value reported previously; however, the analytical approach and data analysis suffered from various technical limitations at the time and therefore warrants re-examination. To address this apparent discrepancy, we determined the KD of soluble SLAMF1 using sedimentation velocity analytical ultracentrifuge (SV-AUC). A globally fitted monomer-dimer model properly explains the data from a wide concentration range obtained with both UV and fluorescence detection systems. The analysis suggests the dimerization KD value for human SLAMF1 is 0.48 µM. Additionally, our data show that SLAMF1 self-association is not driven by non-specific binding to glycans supporting the view of specific protein-protein interaction. We anticipate antibody biotherapeutics capable of modulating the biological consequences of SLAMF1 interactions will be readily identified.

Asunto(s)

Miembro 1 de la Familia de Moléculas Señalizadoras de la Activación Linfocitaria/análisis , Ultracentrifugación , Dimerización , Humanos

RESUMEN

Plant-derived polysaccharides possess potential health benefits that improve intestinal health and the immune system. Molokhia leaves have a large amount of mucilage polysaccharide; in the present study, crude polysaccharide extract was prepared from molokhia leaves. The molecular weight of molokhia leaf polysaccharide fraction (MPF) was estimated to be 51.2 × 103 Da. Polysaccharide was methylated and the structure of MPF was mainly composed of rhamnogalacturonan-I structure with side chains, such as galactans and linear glucan (starch), as shown by GC-MS analysis. To study the biofunctional effects of MPF, its prebiotic and intestinal immune-enhancing activities were assayed in vitro. MPF exhibited good prebiotic activity, as shown by its high prebiotic scores, and increased contents of total short-chain fatty acids on five probiotic strains. In addition, MPF showed immune-enhancing activity on Peyer's patches, as revealed by the high bone marrow cell proliferating activity and production of immunoglobulin A and cytokines. These results demonstrate that MPF may be a potential beneficial prebiotic and intestinal immune-enhancer, which may have wide implications in the food industry.

Asunto(s)

Corchorus/metabolismo , Pectinas/química , Pectinas/farmacología , Animales , Médula Ósea/efectos de los fármacos , Corchorus/química , Carbohidratos de la Dieta/farmacología , Femenino , Galactanos/farmacología , Cromatografía de Gases y Espectrometría de Masas/métodos , Intestinos/efectos de los fármacos , Mesotelina , Ratones , Ratones Endogámicos C3H , Pectinas/metabolismo , Extractos Vegetales/metabolismo , Hojas de la Planta/química , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Polisacáridos/química , Prebióticos

RESUMEN

Toll-like receptors (TLRs) have a crucial role in the recognition of pathogens and initiation of immune responses1-3. Here we show that a previously uncharacterized protein encoded by CXorf21-a gene that is associated with systemic lupus erythematosus4,5-interacts with the endolysosomal transporter SLC15A4, an essential but poorly understood component of the endolysosomal TLR machinery also linked to autoimmune disease4,6-9. Loss of this type-I-interferon-inducible protein, which we refer to as 'TLR adaptor interacting with SLC15A4 on the lysosome' (TASL), abrogated responses to endolysosomal TLR agonists in both primary and transformed human immune cells. Deletion of SLC15A4 or TASL specifically impaired the activation of the IRF pathway without affecting NF-κB and MAPK signalling, which indicates that ligand recognition and TLR engagement in the endolysosome occurred normally. Extensive mutagenesis of TASL demonstrated that its localization and function relies on the interaction with SLC15A4. TASL contains a conserved pLxIS motif (in which p denotes a hydrophilic residue and x denotes any residue) that mediates the recruitment and activation of IRF5. This finding shows that TASL is an innate immune adaptor for TLR7, TLR8 and TLR9 signalling, revealing a clear mechanistic analogy with the IRF3 adaptors STING, MAVS and TRIF10,11. The identification of TASL as the component that links endolysosomal TLRs to the IRF5 transcription factor via SLC15A4 provides a mechanistic explanation for the involvement of these proteins in systemic lupus erythematosus12-14.

Asunto(s)

Factores Reguladores del Interferón/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Lisosomas/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Receptor Toll-Like 7/metabolismo , Receptor Toll-Like 8/metabolismo , Receptor Toll-Like 9/metabolismo , Secuencias de Aminoácidos , Animales , Femenino , Humanos , Inmunidad Innata , Interferón Tipo I/inmunología , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Péptidos y Proteínas de Señalización Intracelular/genética , Lupus Eritematoso Sistémico/metabolismo , Masculino , Proteínas de Transporte de Membrana/deficiencia , Proteínas de Transporte de Membrana/genética , Proteínas del Tejido Nervioso/deficiencia , Proteínas del Tejido Nervioso/genética , Unión Proteica , Transducción de Señal

RESUMEN

Excessive alcohol consumption can increase gut permeability and alter the gut bacterial communities, influencing the pathogenesis of several disorders including alcoholic liver disease, endotoxemia, and systemic inflammation. Although recent studies have highlighted a pivotal role for gut microbiota in alcohol metabolism and alcoholic liver injury, the results have primarily been obtained from binge models treated with physiologically acute dose of alcohol. We sought to investigate the effect of low-dose (0.8 g/kg/day) and short-term (one week) consumption of alcohol on changes in gut microbiota composition in mice. The low-dose consumption of alcohol immediately altered fecal microbiota composition in mice after 1 and 7 days of treatment. We also evaluated the influence of alcoholic beverages containing various microbes using fermented rice liquors (FRLs, called Makgeolli in Korea) on gut microbiota and systemic inflammation. One week of FRLs consumption restored fecal microbiota compositions altered by alcohol administration in mice, with the abundance of Bacteroidetes and Firmicutes phyla recovered to levels of the control group. In addition, mice receiving FRLs exhibited increased fecal production of short-chain fatty acids (SCFA) such as butyric acid and propionic acid within 7 days, and reduced inflammatory responses induced by alcohol administration in the serum and colon. Taken together, these results suggest that short-term and low-dose alcohol intake induces alterations in fecal microbiota composition, and FRLs administration can restore microbial composition and suppress intestinal inflammation, highlighting potential benefits of FRLs as fermented foods.

Asunto(s)

Consumo de Bebidas Alcohólicas/efectos adversos , Microbioma Gastrointestinal , Oryza/química , Animales , Bacterias/clasificación , Biología Computacional , Ácidos Grasos Volátiles , Heces/química , Heces/microbiología , Fermentación , Microbiología de Alimentos , Masculino , Ratones , Ratones Endogámicos C57BL

RESUMEN

Nuruk is a fermentation agent used to manufacture alcoholic beverages, which contains a variety of microorganisms. Most microorganisms in Nuruk are useful for the production of alcoholic beverages; however, Nuruk can be infected with Aspergillus flavus, which produces aflatoxin (AF). Therefore, this study analyzed total AF concentrations in Nuruk, the transfer of AF from Nuruk to alcoholic beverages, and AF-producing microorganisms to determine the safety of alcoholic beverages with respect to this toxin. ELISA showed that total AF levels in 14 of 61 Nuruk samples exceeded 15 ppb, the Korean permissible level in cereal products. In alcoholic beverages produced with Nuruk containing AF levels >15 ppb, only AF G1 was detected, at a level of 0.3 ppb, and the transfer ratio of AF G1 was approximately 1.2% to 1.3%. The dominant genera in Nuruk were Aspergillus and Rhizopus. Among 30 strains belonging to Aspergillus, 10 produced only AF B1 at levels of 0.1 to 2.4 ppb after incubation at 25 °C for 8 days on potato dextrose agar plates. Although AF in Nuruk was rarely transferred to alcoholic beverages and the aflatoxigenic strains were found to possess poor AF-producing capacity, further efforts to reduce AF in Nuruk are needed to ensure the safety of alcoholic beverages.

Asunto(s)

Aflatoxinas/análisis , Bebidas Alcohólicas/análisis , Aflatoxinas/metabolismo , Bebidas Alcohólicas/microbiología , Aspergillus flavus/metabolismo , Grano Comestible/química , Grano Comestible/metabolismo , Grano Comestible/microbiología , Fermentación , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Rhizopus/metabolismo , Almidón/análisis , Almidón/metabolismo

RESUMEN

In the present study, we aimed to determine the cause of surface film formation in three rice vinegars fermented using the traditional static fermentation method. The pH and total acidity of vinegar were 3.0-3.3 and 3.0-8.7%, respectively, and acetic acid was the predominant organic acid present. Colonies showing a clear halo on GYC medium were isolated from the surface film of all vinegars. Via 16S rDNA sequencing, all of the isolates were identified as Acetobacter pasteurianus. Furthermore, field-emission scanning electron microscopy analysis showed that the bacterial cells had a rough surface, were rod-shaped, and were ∼1 × 2 µm in size. Interestingly, cells of the isolate from one of the vinegars were surrounded with an extremely fine threadlike structure. Thus, our results suggest that formation of the surface film in rice vinegar was attributable not to external contamination, to the production of bacterial cellulose by A. pasteurianus to withstand the high concentrations of acetic acid generated during fermentation. However, because of the formation of a surface film in vinegar is undesirable from an industrial perspective, further studies should focus on devising a modified fermentation process to prevent surface film formation and consequent quality degradation.

RESUMEN

In this study, a total of 58 different kinds of nuruk (a traditional Korean fermentation starter) were prepared, including 46 kinds of restored nuruk from ancient documents. Each nuruk was evaluated by analysis of its saccharification power, and the enzyme activities of glucoamylase, α-amylase, ß-amylase, protease, and ß-glucanase. The range of saccharification power (sp) of the restored nuruk ranged between 85 and 565 sp. The diastatic enzymes, α-amylase, ß-amylase, and glucoamylase, were significantly correlated to the saccharification power value; conversely, ß-glucanase and protease did not have a correlative relationship with saccarification power. In addition, their brewing properties on chemical and organoleptic aspects of traditional alcoholic beverage production were compared. Each raw and supplementary material contained in nuruk showed its own unique characteristics on Korean alcoholic beverage brewing. For the first time, in this study, the traditional Korean nuruk types mentioned in ancient documents were restored using modernized production methods, and also characterized based on their brewing properties. Our results could be utilized as a basis for further study of traditional alcoholic beverages and their valuable microorganisms.

Asunto(s)

Fermentación , Microbiología de Alimentos , Hongos/enzimología , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimología , Bebidas Alcohólicas/microbiología , Activación Enzimática , Pruebas de Enzimas , Glucano 1,4-alfa-Glucosidasa/metabolismo , Glicósido Hidrolasas , Concentración de Iones de Hidrógeno , Péptido Hidrolasas/metabolismo , República de Corea , Saccharomyces cerevisiae/clasificación , Temperatura , alfa-Amilasas/metabolismo , beta-Amilasa/metabolismo

RESUMEN

Tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) is an adapter protein that mediates a wide array of protein-protein interactions via its TRAF domain and a RING finger domain that possesses non-conventional E3 ubiquitin ligase activity. First identified nearly two decades ago as a mediator of interleukin-1 receptor (IL-1R)-mediated activation of NFκB, TRAF6 has since been identified as an actor downstream of multiple receptor families with immunoregulatory functions, including members of the TNFR superfamily, the Toll-like receptor (TLR) family, tumor growth factor-ß receptors (TGFßR), and T-cell receptor (TCR). In addition to NFκB, TRAF6 may also direct activation of mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K), and interferon regulatory factor pathways. In the context of the immune system, TRAF6-mediated signals have proven critical for the development, homeostasis, and/or activation of B cells, T cells, and myeloid cells, including macrophages, dendritic cells, and osteoclasts, as well as for organogenesis of thymic and secondary lymphoid tissues. In multiple cellular contexts, TRAF6 function is essential not only for proper activation of the immune system but also for maintaining immune tolerance, and more recent work has begun to identify mechanisms of contextual specificity for TRAF6, involving both regulatory protein interactions, and messenger RNA regulation by microRNAs.

Asunto(s)

Sistema Inmunológico/metabolismo , Factor 6 Asociado a Receptor de TNF/metabolismo , Animales , Homeostasis , Humanos , Sistema Inmunológico/crecimiento & desarrollo , Tolerancia Inmunológica , Activación de Linfocitos , Transducción de Señal , Receptores Toll-Like/metabolismo

RESUMEN

Numerous factors such as geographical origin, cultivar, climate, cultural practices, and manufacturing processes influence the chemical compositions of tea, in the same way as growing conditions and grape variety affect wine quality. However, the relationships between these factors and tea chemical compositions are not well understood. In this study, a new approach for non-targeted or global analysis, i.e., metabolomics, which is highly reproducible and statistically effective in analysing a diverse range of compounds, was used to better understand the metabolome of Camellia sinensis and determine the influence of environmental factors, including geography, climate, and cultural practices, on tea-making. We found a strong correlation between environmental factors and the metabolome of green, white, and oolong teas from China, Japan, and South Korea. In particular, multivariate statistical analysis revealed strong inter-country and inter-city relationships in the levels of theanine and catechin derivatives found in green and white teas. This information might be useful for assessing tea quality or producing distinct tea products across different locations, and highlights simultaneous identification of diverse tea metabolites through an NMR-based metabolomics approach.

Asunto(s)

Camellia sinensis/química , Camellia sinensis/metabolismo , Extractos Vegetales/análisis , Té/química , Té/metabolismo , Geografía , Metabolómica/métodos , Extractos Vegetales/química

RESUMEN

Naive T cell populations are maintained in the periphery at relatively constant levels via mechanisms that control expansion and contraction and are associated with competition for homeostatic cytokines. It has been shown that in a lymphopenic environment naive T cells undergo expansion due, at least in part, to additional availability of IL-7. We have previously found that T cell-intrinsic deletion of TNFR-associated factor (TRAF) 6 (TRAF6ΔT) in mice results in diminished peripheral CD8 T cell numbers. In this study, we report that whereas naive TRAF6ΔT CD8 T cells exhibit normal survival when transferred into a normal T cell pool, proliferation of naive TRAF6ΔT CD8 T cells under lymphopenic conditions is defective. We identified IL-18 as a TRAF6-activating factor capable of enhancing lymphopenia-induced proliferation (LIP) in vivo, and that IL-18 synergizes with high-dose IL-7 in a TRAF6-dependent manner to induce slow, LIP/homeostatic-like proliferation of naive CD8 T cells in vitro. IL-7 and IL-18 act synergistically to upregulate expression of IL-18R genes, thereby enhancing IL-18 activity. In this context, IL-18R signaling increases PI3K activation and was found to sensitize naive CD8 T cells to a model noncognate self-peptide ligand in a way that conventional costimulation via CD28 could not. We propose that synergistic sensitization by IL-7 and IL-18 to self-peptide ligand may represent a novel costimulatory pathway for LIP.

Asunto(s)

Linfocitos T CD8-positivos/inmunología , Interleucina-18/inmunología , Interleucina-7/inmunología , Linfopenia/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Factor 6 Asociado a Receptor de TNF/genética , Animales , Antígenos CD28/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Proteínas de Homeodominio/genética , Interleucina-18/farmacología , Interleucina-7/farmacología , Activación de Linfocitos/inmunología , Recuento de Linfocitos , Linfopenia/genética , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fosfatidilinositol 3-Quinasas/inmunología , Receptores de Interleucina-18/biosíntesis , Transducción de Señal/inmunología , Regulación hacia Arriba

RESUMEN

UNLABELLED: In Korean rice wine (makgeolli) model, we tried to develop a prediction model capable of eliciting a quantitative relationship between initial amino acids in makgeolli mash and major aromatic compounds, such as fusel alcohols, their acetate esters, and ethyl esters of fatty acids, in makgeolli brewed. Mass-spectrometry-based electronic nose (MS-EN) was used to qualitatively discriminate between makgeollis made from makgeolli mashes with different amino acid compositions. Following this measurement, headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry (GC-MS) combined with partial least-squares regression (PLSR) method was employed to quantitatively correlate amino acid composition of makgeolli mash with major aromatic compounds evolved during makgeolli fermentation. In qualitative prediction with MS-EN analysis, the makgeollis were well discriminated according to the volatile compounds derived from amino acids of makgeolli mash. Twenty-seven ion fragments with mass-to-charge ratio (m/z) of 55 to 98 amu were responsible for the discrimination. In GC-MS combined with PLSR method, a quantitative approach between the initial amino acids of makgeolli mash and the fusel compounds of makgeolli demonstrated that coefficient of determination (R(2)) of most of the fusel compounds ranged from 0.77 to 0.94 in good correlation, except for 2-phenylethanol (R(2) = 0.21), whereas R(2) for ethyl esters of MCFAs including ethyl caproate, ethyl caprylate, and ethyl caprate was 0.17 to 0.40 in poor correlation. PRACTICAL APPLICATION: The amino acids have been known to affect the aroma in alcoholic beverages. In this study, we demonstrated that an electronic nose qualitatively differentiated Korean rice wines (makgeollis) by their volatile compounds evolved from amino acids with rapidity and reproducibility and successively, a quantitative correlation with acceptable R2 between amino acids and fusel compounds could be established via HS-SPME GC-MS combined with partial least-squares regression. Our approach for predicting the quantities of volatile compounds in the finished product from initial condition of fermentation will give an insight to food researchers to modify and optimize the qualities of the corresponding products.

Asunto(s)

Aminoácidos/análisis , Nariz Electrónica , Odorantes/análisis , Oryza/química , Compuestos Orgánicos Volátiles/análisis , Vino/análisis , Acetatos/análisis , Alcoholes/análisis , Ésteres/análisis , Fermentación , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Corea (Geográfico) , Modelos Teóricos , Alcohol Feniletílico/análisis , Reproducibilidad de los Resultados , Microextracción en Fase Sólida/métodos

RESUMEN

Fatty acids (FAs) are essential constituents of cell membranes, signaling molecules, and bioenergetic substrates. Because CD8(+) T cells undergo both functional and metabolic changes during activation and differentiation, dynamic changes in FA metabolism also occur. However, the contributions of de novo lipogenesis to acquisition and maintenance of CD8(+) T cell function are unclear. In this article, we demonstrate the role of FA synthesis in CD8(+) T cell immunity. T cell-specific deletion of acetyl coenzyme A carboxylase 1 (ACC1), an enzyme that catalyzes conversion of acetyl coenzyme A to malonyl coenzyme A, a carbon donor for long-chain FA synthesis, resulted in impaired peripheral persistence and homeostatic proliferation of CD8(+) T cells in naive mice. Loss of ACC1 did not compromise effector CD8(+) T cell differentiation upon listeria infection but did result in a severe defect in Ag-specific CD8(+) T cell accumulation because of increased death of proliferating cells. Furthermore, in vitro mitogenic stimulation demonstrated that defective blasting and survival of ACC1-deficient CD8(+) T cells could be rescued by provision of exogenous FA. These results suggest an essential role for ACC1-mediated de novo lipogenesis as a regulator of CD8(+) T cell expansion, and may provide insights for therapeutic targets for interventions in autoimmune diseases, cancer, and chronic infections.

Asunto(s)

Acetil-CoA Carboxilasa/inmunología , Linfocitos T CD8-positivos/inmunología , Proliferación Celular , Ácidos Grasos/inmunología , Homeostasis/inmunología , Acetil-CoA Carboxilasa/genética , Acetil-CoA Carboxilasa/metabolismo , Animales , Linfocitos T CD8-positivos/metabolismo , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Células Cultivadas , Ácidos Grasos/metabolismo , Citometría de Flujo , Expresión Génica/inmunología , Interacciones Huésped-Patógeno/inmunología , Antígenos Comunes de Leucocito/inmunología , Antígenos Comunes de Leucocito/metabolismo , Lipogénesis/genética , Lipogénesis/inmunología , Listeria monocytogenes/genética , Listeria monocytogenes/inmunología , Listeria monocytogenes/fisiología , Listeriosis/genética , Listeriosis/inmunología , Listeriosis/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ovalbúmina/genética , Ovalbúmina/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa

RESUMEN

A commercial electronic tongue was used to discriminate Korean rice wines (makgeolli) brewed from nine cultivars of rice with different amino acid and fatty acid compositions. The E-tongue was applied to establish prediction models with sensory evaluation or LC-MS/MS by partial least squares regression (PLSR). All makgeollis were classified into three groups by principal components analysis, and the separation pattern was affected by rice qualities and yeast fermentation. Makgeolli taste changed from the complicated comprising sweetness, saltiness, and umami to the uncomplicated, such as bitterness and then, sourness, with a decrease of amino acids and fatty acids in the rice. The quantitative correlation between E-tongue and sensory scores or LC-MS/MS by PLSR demonstrated that E-tongue could well predict most of the sensory attributes with relatively acceptable r(2), except for bitterness, but could not predict most of the chemical compounds responsible for taste attributes, except for ribose, lactate, succinate, and tryptophan.

Asunto(s)

Electrónica/instrumentación , Vino/análisis , Electrónica/métodos , Fermentación , Análisis de los Alimentos , Oryza/química , Gusto

RESUMEN

Makgeolli, also known as Takju, is a non-filtered traditional Korean alcoholic beverage that contains various floating matter, including yeast cells, which contributes to its high physiological functionality. In the present study, we assessed the levels of ß-glucan and glutathione in various yeast strains isolated from traditional Korean Nuruk and selected a ß-glucan- and glutathione-rich yeast strain to add value to Makgeolli by enhancing its physiological functionality through increased levels of these compounds. Yeast ß-glucan levels ranged from 6.26% to 32.69% (dry basis) and were strongly species-dependent. Dried Saccharomyces cerevisiae isolated from Nuruk contained 25.53 µg/mg glutathione, 0.70 µg/mg oxidized glutathione, and 11.69 µg/g and 47.85 µg/g spermidine and L-ornithine monohydrochloride, respectively. To produce functional Makgeolli, a ß-glucan- and glutathione-rich yeast strain was selected in a screening analysis. Makgeolli fermented with the selected yeast strain contained higher ß-glucan and glutathione levels than commercial Makgeolli. Using the selected yeast strain to produce Makgeolli with high ß-glucan and glutathione content may enable the production of functional Makgeolli.

RESUMEN

Dendritic cells (DCs) are a heterogeneous group of professional antigen presenting cells that lie in a nexus between innate and adaptive immunity because they recognize and respond to danger signals and subsequently initiate and regulate effector T-cell responses. Initially thought to be absent from the CNS, both plasmacytoid and conventional DCs as well as DC precursors have recently been detected in several CNS compartments where they are seemingly poised for responding to injury and pathogens. Additionally, monocyte-derived DCs rapidly accumulate in the inflamed CNS where they, along with other DC subsets, may function to locally regulate effector T-cells and/or carry antigens to CNS-draining cervical lymph nodes. In this review we highlight recent research showing that (a) distinct inflammatory stimuli differentially recruit DC subsets to the CNS; (b) DC recruitment across the blood-brain barrier (BBB) is regulated by adhesion molecules, growth factors, and chemokines; and (c) DCs positively or negatively regulate immune responses in the CNS.

Asunto(s)

Sistema Nervioso Central/inmunología , Células Dendríticas/inmunología , Encefalitis/inmunología , Inmunidad Innata/inmunología , Mielitis/inmunología , Animales , Humanos , Receptor Cross-Talk/inmunología

RESUMEN

Lactic acid bacteria play important roles in various fermented foods in Asia. Besides being the main component in kimchi and other fermented foods, they are used to preserve edible food materials through fermentation of other raw-materials such as rice wine/beer, rice cakes, and fish by producing organic acids to control putrefactive microorganisms and pathogens. These bacteria also provide a selective environment favoring fermentative microorganisms and produce desirable flavors in various fermented foods. This paper discusses the role of lactic acid bacteria in various non-dairy fermented food products in Asia and their nutritional and physiological functions in the Asian diet.

Asunto(s)

Microbiología de Alimentos/métodos , Ácido Láctico/metabolismo , Lactobacillales/metabolismo , Fermentación , Humanos