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1.
AMB Express ; 14(1): 14, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38282124

RESUMEN

Efficient utilization of galactose by microorganisms can lead to the production of valuable bio-products and improved metabolic processes. While Bacillus subtilis has inherent pathways for galactose metabolism, there is potential for enhancement via evolutionary strategies. This study aimed to boost galactose utilization in B. subtilis using adaptive laboratory evolution (ALE) and to elucidate the genetic and metabolic changes underlying the observed enhancements. The strains of B. subtilis underwent multiple rounds of adaptive laboratory evolution (approximately 5000 generations) in an environment that favored the use of galactose. This process resulted in an enhanced specific growth rate of 0.319 ± 0.005 h-1, a significant increase from the 0.03 ± 0.008 h-1 observed in the wild-type strains. Upon selecting the evolved strain BSGA14, a comprehensive whole-genome sequencing revealed the presence of 63 single nucleotide polymorphisms (SNPs). Two of them, located in the coding sequences of the genes araR and glcR, were found to be the advantageous mutations after reverse engineering. The strain with these two accumulated mutations, BSGALE4, exhibited similar specific growth rate on galactose to the evolved strain BSGA14 (0.296 ± 0.01 h-1). Furthermore, evolved strain showed higher productivity of protease and ß-galactosidase in mock soybean biomass medium. ALE proved to be a potent tool for enhancing galactose metabolism in B. subtilis. The findings offer valuable insights into the potential of evolutionary strategies in microbial engineering and pave the way for industrial applications harnessing enhanced galactose conversion.

2.
Microorganisms ; 11(9)2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37764128

RESUMEN

Nitric oxide (NO) is a free radical associated with physiological functions such as blood pressure regulation, cardiovascular health, mitochondrial production, calcium transport, oxidative stress, and skeletal muscle repair. This study aimed to isolate Latilactobacillus curvatus strains with enhanced NO production from the traditional Korean fermented food, jangajji, and evaluate their probiotic properties for industrial purposes. When cells were co-cultured with various bacterial stimulants, NO production generally increased, and NO synthesis was observed in the range of 20-40 mg/mL. The selected strains of Lat. curvatus were resistant to acid and bile conditions and with variable effectiveness (1-14%) in adhering to Caco-2 cells. Most bacterial strains can inhibit the growth of various pathogens. In addition, they are capable of reducing cholesterol levels via assimilation of cholesterol at 10-50%. Among the selected NO synthases from Lat. curvatus strains, the strain JBCC38 showed the highest capacity to scavenge ABTS (30.1%) and DPPH radicals (39.4%). Moreover, these strains exhibited immunomodulatory properties. The production of TNF-α and IL-6 in the macrophages treated with various bacterial stimulants was induced in all the selected strains.

3.
Microorganisms ; 11(8)2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37630480

RESUMEN

To understand the biological roles of Pediococcus pentosaceus strains as probiotics isolated from the traditional Korean fermented food, Jangajji, Pediococcus pentosaceus was selected based on its high cinnamoyl esterase (CE) and antioxidant activities. The acid and bile stability, intestinal adhesion, antagonistic activity against human pathogens, cholesterol-lowering effects, and immune system stimulation without inflammatory effects were evaluated. Nitric oxide (NO) levels were measured in co-culture with various bacterial stimulants. Fermentation ability was measured by using a broccoli matrix and the sulforaphane levels were measured. Resistance to acidic and bilious conditions and 8% adherence to Caco-2 cells were observed. Cholesterol levels were lowered by 51% by assimilation. Moreover, these strains exhibited immunomodulatory properties with induction of macrophage TNF-α and IL-6 and had microstatic effects on various pathogens. Co-culture with various bacterial stimulants resulted in increased NO production. Fermentation activity was increased with the strains, and higher sulforaphane levels were observed. Therefore, in the future, the applicability of the selected strain to broccoli matrix-based fermented functional foods should be confirmed.

4.
Foods ; 11(12)2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35741909

RESUMEN

Ginsenoside Rf (G-Rf) is a saponin of the protopanaxatriol family and a bioactive component of Korean ginseng. Several ginsenosides are known to have a positive effect on exercise endurance, but there is not yet a report on that of G-Rf. Forced swimming tests were performed on G-Rf-treated mice to evaluate the effect of G-Rf on exercise endurance. Subsequently, the expression of markers related to myoblast differentiation and mitochondrial biogenesis in murine skeletal C2C12 myotubes and tibialis anterior muscle tissue was determined using Western blotting, quantitative real-time polymerase chain reaction, and immunofluorescence staining to elucidate the mechanism of action of G-Rf. The swimming duration of the experimental animal was increased by oral gavage administration of G-Rf. Moreover, G-Rf significantly upregulated the myoblast differentiation markers, mitochondrial biogenesis markers, and its upstream regulators. In particular, the mitochondrial biogenesis marker increased by G-Rf was decreased by each inhibitor of the upstream regulators. G-Rf enhances exercise endurance in mice, which may be mediated by myoblast differentiation and enhanced mitochondrial biogenesis through AMPK and p38 MAPK signaling pathways, suggesting that it increases energy production to satisfy additional needs of exercising muscle cells. Therefore, G-Rf is an active ingredient in Korean ginseng responsible for improving exercise performance.

5.
Food Sci Biotechnol ; 31(7): 787-796, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35720463

RESUMEN

Chlorophyll-rich samples, such as kale, interfere with the analysis of residual pesticides and adversely affect the integrity of tandem mass spectrometers. Dispersed solid-phase (d-SPE) extraction using graphitized carbon black effectively removes pigments from kale extracts; however, it also reduces the recoveries of 30 pesticides. To overcome this, alternative sorbents, including ENVI-Carb, ChloroFiltr, and Z-Sep+, were evaluated in this study. A sorbent combination based on 50 mg of Z-Sep+ was most advantageous (21/30), good precision (< 15%), excellent pigment removal capacity, and low matrix effect. The limit of quantification (0.0001-0.0040 mg/kg) was lower than the Korean maximum residue limits levels. The proposed method was validated according to international guidelines and applied to real kale samples. The results demonstrated that d-SPE using Z-Sep+ provides an effective strategy for ensuring mass spectrometry system integrity and improving the analytical accuracy in chlorophyll-rich samples. Supplementary information: The online version contains supplementary material available at 10.1007/s10068-022-01101-3.

6.
Microorganisms ; 9(11)2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34835374

RESUMEN

Conjugated linoleic acid (CLA) isomers are potent health-promoting fatty acids. This study evaluated the probiotic properties of 10 strains of high CLA-producing lactic acid bacteria (LAB) isolated from Jeot-gal, a high-salt, fermented seafood. Two isolates, Lactiplantibacillus plantarum JBCC105683 and Lactiplantibacillus pentosus JBCC105676, produced the largest amounts of CLA (748.8 and 726.9 µg/mL, respectively). Five isolates, L. plantarum JBCC105675, L. pentosus JBCC105676, L. pentosus JBCC105674, L. plantarum JBCC105683, and Lactiplantibacillus paraplantarum JBCC105655 synthesized more cis-9, trans-11-CLA than trans-10, cis-12-CLA (approximately 80:20 ratio). All the strains survived severe artificial acidic environments and showed antimicrobial activity and strong adhesion capability to Caco-2 cells as compared to the commercial strain Lactocaseibacillus rhamnosus GG. Among them, Pediococcus acidilactici JBCC105117, L. paraplantarum JBCC105655, and L. plantarum JBCC105683 strongly stimulated the immunological regulatory gene PMK-1 and the host defense antimicrobial peptide gene clec-60 in Caenorhabditis elegans. Moreover, three strains showed a significant induction of tumor necrosis factor-α, interleukin (IL)-1ß, IL-6, IL-12, and IL-10 production in RAW 264.7 macrophages, indicating that they were promising candidates for probiotics with high CLA-converting activity. Our results indicate that the newly isolated CLA-producing LAB might be useful as a functional probiotic with beneficial health effects that modulate the immune system.

7.
Food Res Int ; 141: 109942, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33641948

RESUMEN

This study aimed to comparatively analyze the volatile flavor of rooibos tea (Aspalathus linearis) obtained by two commonly used flavor extraction methods, simultaneous distillation-extraction (SDE) and steam distillation under reduced pressure (DRP). The tea obtained by the two extraction methods, were analyzed by gas chromatography-mass spectrometry to identify volatile aroma-related compounds. Descriptive sensory analysis of the extracted rooibos tea flavor was carried out by a trained panel (n = 7). Fifty volatile compounds were identified, including 26 and 25 aroma-active compounds by SDE (45.9 µg/g) and DRP (37.5 µg/g), respectively. SDE recovered larger quantities of alcohols, acids, and esters, whereas DRP was useful for analyzing thermally unstable volatile compounds, including various alcohols, aldehydes, and hydrocarbons. Descriptive sensory analysis revealed that ketones and phenolic compounds may be responsible for the sensory attributes woody and grassy green, whereas the aldehydes and acidic compounds may contribute to floral and fruity.


Asunto(s)
Aspalathus , Compuestos Orgánicos Volátiles , Cromatografía de Gases y Espectrometría de Masas , Humanos , Percepción , , Compuestos Orgánicos Volátiles/análisis
8.
Int J Biol Macromol ; 164: 3835-3845, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32835798

RESUMEN

In the present study, to verify the effect of polysaccharides derived from persimmon leaves (PLE) at epithelial-to-mesenchymal transition (EMT), A549 cells were treated with TGF-ß1 alone or co-treated with TGF-ß1 and PLE (50 and 75 µg/mL). PLE-treated cells showed higher expression of E-cadherin and lower expression of N-cadherin and vimentin compared to TGF-ß1-treated cells by inhibiting the levels of transcription factors, including Snail, Slug, and ZEB1, all associated with EMT. PLE also significantly decreased migration, invasion, and anoikis resistance through TGF-ß1 mediated EMT suppression, whereby PLE inhibited the levels of MMP-2 and MMP-9 while cleaving PARP. These inhibitory effects of PLE against EMT, migration, invasion, and anoikis resistance were determined by activating the canonical SMAD2/3 and non-canonical ERK/p38 signaling pathways. Therefore, these results suggest that PLE could be used as a potential chemical therapeutic agent for early metastasis of lung cancer in vitro.


Asunto(s)
Diospyros/química , Transición Epitelial-Mesenquimal/efectos de los fármacos , Hojas de la Planta/química , Polisacáridos/aislamiento & purificación , Polisacáridos/farmacología , Factor de Crecimiento Transformador beta1/farmacología , Células A549 , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Metaloproteinasa 1 de la Matriz , Polisacáridos/química , Proteínas Recombinantes , Transducción de Señal/efectos de los fármacos , Factores de Transcripción/genética
9.
J Food Sci ; 85(4): 1098-1104, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32147835

RESUMEN

Newly developed magnetic carbon particles prepared from coffee grounds were used as the sorbent for the magnetic solid-phase extraction of eight phthalic acid esters (PAEs) from plastic bottled water prior to their analysis by GC-MS. The method, which uses coffee-ground particles coated with iron oxide, was validated, and exhibited linearities for the eight PAEs, with coefficients of determination above 0.998 in the 0.005 to 0.1 mg/L concentration range. Limits of detection and limits of quantification of 0.00003 to 0.002 mg/L and 0.0001 to 0.005 mg/L, respectively, were achieved, with recoveries (%) ranging between 77% and 120%, and relative standard deviations for intra- and interday precisions below 16.3% at three fortification levels. No PAE residues were detected when the developed and validated method was applied to 10 real plastic bottled water samples. Taken together, the developed magnetic solid-phase extraction method is a useful tool for monitoring phthalate esters in aqueous samples. PRACTICAL APPLICATION: The development of a new, inexpensive, and efficient magnetic sorption material derived from spent coffee grounds, and its ability to determine phthalate esters in aqueous solutions was described by GC-MS/MS. The developed magnetic solid-phase extraction method is a useful tool for monitoring phthalate esters in aqueous samples.


Asunto(s)
Coffea/química , Agua Potable/análisis , Ésteres/aislamiento & purificación , Magnetismo/métodos , Ácidos Ftálicos/aislamiento & purificación , Plásticos/aislamiento & purificación , Extracción en Fase Sólida/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Carbono/química , Ésteres/química , Cromatografía de Gases y Espectrometría de Masas , Límite de Detección , Magnetismo/instrumentación , Ácidos Ftálicos/análisis , Plásticos/química , Semillas/química , Extracción en Fase Sólida/instrumentación , Contaminantes Químicos del Agua/química
10.
Foods ; 8(7)2019 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-31336601

RESUMEN

The monitoring of food quality and safety requires a suitable analytical method with simultaneous detection in order to control pesticide and herbicide residues. In this study, a novel analytical method, referred to as "dispersive solid-liquid extraction", was applied to monitor seven sulfonylurea herbicides in strawberries. This method was optimized in terms of the amount of C18 and the volume of added water, and it was validated through satisfactory linearities (R2 > 0.99), recoveries of 70% to 84% with acceptable precisions, and limits of quantification lower than the maximum residue limits for the seven sulfonylurea herbicides in strawberries. The cleanup efficiency of the dispersive solid-liquid extraction technique was compared to that of the QuEChERS- ("quick, easy, cheap, effective, rugged and safe") based method with dispersive solid phase extraction. The recoveries of the former were found to be comparable to those involving QuEChERS C18 cleanup (recoveries of 74%-87%). The method was used to determine sulfonylurea herbicide residues in ten strawberry samples. None of the samples had herbicide residues higher than that of limit of quantifications (LOQs) or maximum residue limits (MRLs). The results suggest that the dispersive solid-liquid extraction method combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) is effective for the analysis of sulfonylurea herbicide residues in strawberries.

11.
Food Chem ; 298: 125050, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31260955

RESUMEN

An analytical method involving QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation, followed by LC-MS/MS and GC-MS/MS was developed and validated for the determination of 60 pesticides in eggs. Recoveries of 70-120% were achieved for selected pesticides and relative standard deviations <20% were obtained for most analytes at three concentrations. The limit of quantification was <10 µg kg-1 for 83% of the total pesticides. This method was used to analyze 58 egg samples and the residues of seven pesticides (disulfoton, fipronil sulfone, cyromazine, o,p-DDT, p,p-DDD, p,p-DDT, and permethrin) were quantified in 16 egg samples at levels of 5-10 µg kg-1, which was below the corresponding the maximum residue levels, as established by Korean Ministry of Food and Drug Safety. We demonstrated that LC-MS/MS and GC-MS/MS in combination with QuEChERS can be used to routinely monitor multiple pesticide residues in egg samples.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Animales , Pollos , Cromatografía Líquida de Alta Presión , Disulfotón/análisis , Huevos/análisis , Femenino , Límite de Detección , Pirazoles/análisis , Reproducibilidad de los Resultados
12.
Food Chem ; 293: 438-445, 2019 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-31151632

RESUMEN

In this study, deep eutectic solvents (DESs) coupled with ultrasound-assisted extraction (UAE) were evaluated and optimized for the extraction of major flavonoids from common buckwheat sprouts. Initially, 18 different choline chloride (CC)-based DESs were evaluated as potential extraction solvents, and 80% CCTG (CC-based DES composed of triethylene glycol and 20 vol% water) extracted significantly higher (p < 0.05) amounts of flavonoids than other DESs studied. The extraction efficiency of 80% CCTG was even higher (p < 0.05) than that of methanol for the extraction of vitexin and quercetin-3-O-robinobioside. Procedure using 80% CCTG and UAE were optimized; an extraction temperature of 56 °C and extraction time of 40 min were considered optimal. The optimized extraction procedure was reliable and efficient for the extraction of major flavonoids from common buckwheat sprouts. In addition, flavonoids could be efficiently recovered from DES extracts with high recovery yields (>97%) by using a C18 solid-phase extraction.


Asunto(s)
Fagopyrum/química , Flavonoides/química , Extractos Vegetales/química , Solventes/química , Cromatografía Líquida de Alta Presión , Fagopyrum/metabolismo , Flavonoides/aislamiento & purificación , Extracción en Fase Sólida , Sonicación , Temperatura
13.
Artículo en Inglés | MEDLINE | ID: mdl-31251696

RESUMEN

Pesticides are used to increase crop yields and preserve quality by protecting crops against pests; however, their overuse can adversely affect human health and the environment. Herein, we report the development of a multi-pesticide screening method using optimized QuEChERS coupled with liquid chromatography/quadrupole time-of-flight (QTOF) mass spectrometry for the analysis of 13 pesticides in wheat flour. Mass accuracies with errors of less than 2.4 ppm were obtained for all analysed pesticides, and the method provided satisfactory recovery and linearity. Repeatabilities of 0.3-12.7% and reproducibilities of 2.5-15.2% were observed in full-scan TOF mode. The performance of the developed full-scan TOF method was compared to that obtained in high-resolution multiple reaction monitoring (MRM-HR) mode. The limits of quantification for the full-scan TOF and MRM-HR modes ranged from 2 to 10, and 3 to 9 µg kg-1, respectively. The two quantification methods exhibited high sensitivities (limit of detections: 1-3 µg kg-1 in full-scan TOF, and 1-3 µg kg-1 for MRM-HR mode). No pesticide residues were detected when the developed method was applied to 22 real wheat flour samples.


Asunto(s)
Harina/análisis , Análisis de los Alimentos , Contaminación de Alimentos/análisis , Residuos de Plaguicidas/análisis , Extracción en Fase Sólida , Triticum/química , Cromatografía Líquida de Alta Presión , Espectrometría de Masas , Factores de Tiempo
14.
Food Sci Biotechnol ; 28(2): 481-489, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30956860

RESUMEN

In order to improve the slow ethanol fermentation during acetic acid fermentation process of black raspberry vinegar (BRV), the microbiological and physicochemical aspects of the effects of indigenous Saccharomyces cerevisiae JBCC-21A were examined. The selected S. cerevisiae JBCC-21A showed better growth and ethanol production rates than the commercial yeast strains. The ethanol production rate was 3-times faster than the traditional method. Acetic acid fermentation by S. cerevisiae JBCC-21A began 10 days earlier than the traditional method and reached up to 60 g/L acetic acid. Bacterial counts revealed Acetobacter pasteurianus was the only dominant species throughout the inoculated acetic acid fermentation. The physicochemical and functional properties of the fermented vinegar using indigenous S. cerevisiae JBCC-21A maintained a high quality similar to the traditional method, while being the faster fermentation process. Thus, it is suggested that inoculation of the indigenous S. cerevisiae strain in order to shorten the fermentation time without affecting the quality of traditional BRV.

15.
J Biotechnol ; 298: 57-63, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-30986518

RESUMEN

Streptococcus mutans plays a key role in the development of dental caries and promotes the formation of oral biofilm produced by glucosyltransferases (GTFs). Bacillus velezensis K68 was isolated from traditional fermented foods and inhibits biofilm formation mediated by S. mutans. Gene amplification results demonstrated that B. velezensis K68 contained genes for the biosynthesis of 1-deoxynojirimycin (1-DNJ), a known GTF expression inhibitor. The presence of the GabT1, Yktc1, and GutB1 genes required for 1-DNJ synthesis in B. velezensis K68 was confirmed. Supernatant from B. velezensis K68 culture medium inhibited biofilm formation by 84% when S. mutans was cultured for 48 h, and inhibited it maximally when 1% glucose was added to the S. mutans culture medium as a GTF substrate. In addition, supernatant from B. velezensis K68 medium containing 3 ppb 1-DNJ decreased S. mutans cell surface hydrophobicity by 79.0 ± 0.8% compared with that of untreated control. The supernatant containing 1-DNJ decreased S. mutans adherence by 99.97% and 98.83% under sugar-dependent and sugar-independent conditions, respectively. S. mutans treated with the supernatant exhibited significantly reduced expression of the essential GTF genes gtfB, gtfC, and gtfD compared to that in the untreated group. Thus, B. velezensis inhibits biofilm formation, adhesion, and GTF gene expression of S. mutans through 1-DNJ production.


Asunto(s)
1-Desoxinojirimicina/metabolismo , Bacillus/metabolismo , Caries Dental/microbiología , Streptococcus mutans/metabolismo , Proteínas Bacterianas/genética , Biopelículas/crecimiento & desarrollo , Caries Dental/prevención & control , Regulación Bacteriana de la Expresión Génica , Glucosiltransferasas/antagonistas & inhibidores , Glucosiltransferasas/genética , Humanos , Streptococcus mutans/patogenicidad
16.
J Gen Appl Microbiol ; 65(4): 188-196, 2019 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-30773526

RESUMEN

Biogenic amines (BAs) are widely present in nearly all fermented foods and beverages, and excess consumption can cause adverse health effects. To prepare BA-free Korean black raspberry wine (BRW), four autochthonous starter yeast strains without hazardous BA synthesis activity were selected and their physiological and biochemical properties were examined. The selected strains were identified as Saccharomyces cerevisiae based on 26S rDNA sequencing and microsatellite analysis. Molecular fingerprinting revealed that isolates were quite different from commercial wine yeast S. cerevisiae (52.4% similarity), but genetically relevant to commercial beer yeasts. The four S. cerevisiae strains produced over 10% ethanol during BRW fermentation. In addition, the fermented BRW with these strains showed higher levels of total flavonoids and similar antioxidant activity compared to the control sample. Potentially hazardous BAs that commonly occur in black raspberry extract (BRE) such as cadaverine, histamine, and spermidine were also not detected in the fermented BRW. Thus, we suggest that our strains are promising fermentation tools to ensure high quality and enhanced functionality in the production of BA-free BRW.


Asunto(s)
Aminas Biogénicas/biosíntesis , Fermentación , Rubus/microbiología , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/aislamiento & purificación , Vino/microbiología , Reactores Biológicos , Etanol , Repeticiones de Microsatélite , Saccharomyces cerevisiae/metabolismo
17.
Artículo en Inglés | MEDLINE | ID: mdl-30676884

RESUMEN

The present study aimed to investigate the occurrence of emerging mycotoxins in cereals (n = 61) and cereal-based products (n = 36) collected from Korean market. First of all, using the quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction method, and ultrahigh-pressure liquid chromatography (UPLC) with triple quadruple tandem mass spectrometry (MS/MS), we developed a simple and fast method for quantitative determination of eight emerging mycotoxins including alternariol (AOH), alternariol monomethyl ether (AME), tentoxin (TEN), beauvericin (BEA) and enniatins (ENs; ENA, ENA1, ENB and ENB1). The developed analytical method was validated in parameters of linearity, precision and accuracy. For UPLC-MS/MS analysis, the recoveries of emerging mycotoxins from spiked samples at three concentration levels ranged from 82.7% to 108.8% with RSDs between 0.4% and 14.7%. Analytical methods were applied to determine the contamination of mycotoxins in cereal and cereal-based product samples. Sixty-three of the total 97 samples were contaminated with at least one emerging mycotoxin. The maximum number of emerging mycotoxins observed in a single sample was six out of eight analytes. The highest level of contamination was detected in cereal at 70.9 µg/kg for alternariol monomethyl ether (AME). However, currently there is no international standard for emerging mycotoxins in food. Accordingly, it is necessary to establish a database of emerging mycotoxins contamination through continuous monitoring.


Asunto(s)
Comercio , Grano Comestible/química , Contaminación de Alimentos/análisis , Micotoxinas/análisis , Cromatografía Liquida , República de Corea , Espectrometría de Masas en Tándem
18.
Exp Ther Med ; 14(1): 635-641, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28672978

RESUMEN

Certain strains of lactobacilli have been reported to exert favorable effects on atopic dermatitis (AD). Jeotgal, a traditional Korean food, is a salted fermented seafood known to harbor many lactic acid bacteria. In the present study, two novel lactobacillus strains were isolated from Jeotgal, and their anti-AD effects were investigated. Lactobacilli isolated from Jeotgal were identified, according to conjugated linoleic acid-producing activity, as Lactobacillus plantarum (JBCC105645 and JBCC105683). AD-like skin lesions were induced in BALB/c mice using dinitrofluorobenzene (DNFB). Ear swelling, histological analysis and serum immunoglobulin E (IgE) levels in mice were evaluated to investigate the anti-AD effects of lactobacilli. Cytokine production of ex vivo cluster of differentiation (CD)4+ T cells, and interleukin (IL)-12 production of in vitro macrophages were also evaluated to establish a putative mechanism of the action of lactobacilli. Administration of JBCC105645 or JBCC105683 suppressed ear swelling and serum IgE levels in DNFB-treated mice (P<0.05). Notably, JBCC105645 was more effective than JBCC105683 (P<0.05). Treatment with the lactobacilli also induced a significant decrease in IL-4 production with concomitant increase in interferon (IFN)-γ production in DNFB-exposed CD4+ T cells, and an increase in IL-12 production in macrophages (P<0.05). Taken together, the lactobacilli isolated from Jeotgal may suppress the development of AD-like skin inflammation in mice by modulating IL-4 and IFN-γ production in CD4+ T cells, presumably via enhancing IL-12 production by macrophages.

19.
Braz. j. microbiol ; 47(2): 452-460, Apr.-June 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-780816

RESUMEN

Abstract A high concentration of histamine, one of the biogenic amines (BAs) usually found in fermented foods, can cause undesirable physiological side effects in sensitive humans. The objective of this study is to isolate indigenous Acetobacter strains from naturally fermented Bokbunja vinegar in Korea with reduced histamine production during starter fermentation. Further, we examined its physiological and biochemical properties, including BA synthesis. The obtained strain MBA-77, identified as Acetobacter aceti by 16S rDNA homology and biochemical analysis and named A. aceti MBA-77. A. aceti MBA-77 showed optimal acidity % production at pH 5; the optimal temperature was 25 °C. When we prepared and examined the BAs synthesis spectrum during the fermentation process, Bokbunja wine fermented with Saccharomyces cerevisiae showed that the histamine concentration increased from 2.72 of Bokbunja extract to 5.29 mg/L and cadaverine and dopamine was decreased to 2.6 and 10.12 mg/L, respectively. Bokbunja vinegar prepared by A. aceti MBA-77 as the starter, the histamine concentration of the vinegar preparation step was decreased up to 3.66 mg/L from 5.29 mg/L in the wine preparation step. To our knowledge, this is the first report to demonstrate acetic acid bacteria isolated from Bokbunja seed vinegar with low spectrum BA and would be useful for wellbeing vinegar preparation.


Asunto(s)
Vino/análisis , Aminas Biogénicas/análisis , Acetobacter/metabolismo , Histamina/metabolismo , Rubus/microbiología , Saccharomyces cerevisiae/metabolismo , Vino/microbiología , Acetobacter/aislamiento & purificación , Acetobacter/genética , Histamina/análisis , Ácido Acético/análisis , Ácido Acético/metabolismo , Fermentación , Rubus/metabolismo , Microbiología de Alimentos
20.
Braz J Microbiol ; 47(2): 452-60, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26991285

RESUMEN

A high concentration of histamine, one of the biogenic amines (BAs) usually found in fermented foods, can cause undesirable physiological side effects in sensitive humans. The objective of this study is to isolate indigenous Acetobacter strains from naturally fermented Bokbunja vinegar in Korea with reduced histamine production during starter fermentation. Further, we examined its physiological and biochemical properties, including BA synthesis. The obtained strain MBA-77, identified as Acetobacter aceti by 16S rDNA homology and biochemical analysis and named A. aceti MBA-77. A. aceti MBA-77 showed optimal acidity % production at pH 5; the optimal temperature was 25°C. When we prepared and examined the BAs synthesis spectrum during the fermentation process, Bokbunja wine fermented with Saccharomyces cerevisiae showed that the histamine concentration increased from 2.72 of Bokbunja extract to 5.29mg/L and cadaverine and dopamine was decreased to 2.6 and 10.12mg/L, respectively. Bokbunja vinegar prepared by A. aceti MBA-77 as the starter, the histamine concentration of the vinegar preparation step was decreased up to 3.66mg/L from 5.29mg/L in the wine preparation step. To our knowledge, this is the first report to demonstrate acetic acid bacteria isolated from Bokbunja seed vinegar with low spectrum BA and would be useful for wellbeing vinegar preparation.


Asunto(s)
Acetobacter/metabolismo , Aminas Biogénicas/análisis , Histamina/metabolismo , Rubus/microbiología , Vino/análisis , Ácido Acético/análisis , Ácido Acético/metabolismo , Acetobacter/genética , Acetobacter/aislamiento & purificación , Fermentación , Microbiología de Alimentos , Histamina/análisis , Rubus/metabolismo , Saccharomyces cerevisiae/metabolismo , Vino/microbiología
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