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1.
J Appl Microbiol ; 132(1): 562-570, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34133840

RESUMO

AIMS: Two putative probiotic strains, Lacticaseibacillus (Lc.) rhamnosus BFE5264 and Lactiplantibacillus (Lp.) plantarum NR74, have been shown to suppress cholesterol uptake and promote cholesterol efflux in Caco-2 cells. However, an in vivo beneficial effect of these strains on plasma cholesterol levels has not been verified yet; neither have the underlying mechanisms of regulating cholesterol metabolism clarified thus far. This study has focused on these two aspects. METHODS AND RESULTS: A murine model has been used, and the animals receiving a high-fat/high-cholesterol diet showed elevated plasma cholesterol levels. However, supplementation of Lc. rhamnosus BFE5264 and Lp. plantarum NR74 resulted in the down regulation of Niemann-Pick C1-like 1 (NPC1L1) in the intestine in addition to counteracting the diet-induced suppression of low-density lipoprotein receptor expression in the liver. ATP Binding Cassette Subfamily A Member 1 (ABCA1) was only significantly increased upon administration of Lc. rhamnosus BFE5264. CONCLUSIONS: The present findings demonstrate that supplementation with Lc. rhamnosus BFE5264 and Lp. plantarum NR74 may improve diet-induced hypercholesterolemia by suppression of cholesterol absorption in the small intestine and by supporting the regulation of cholesterol metabolism in the liver. SIGNIFICANCE AND IMPACT OF THE STUDY: This work contributes to understanding the beneficial effects of probiotics on host cholesterol metabolism and underlying mechanisms related to hypercholesterolemia.


Assuntos
Hipercolesterolemia , Probióticos , Animais , Células CACO-2 , Colesterol/metabolismo , Dieta , Humanos , Hipercolesterolemia/metabolismo , Absorção Intestinal , Intestinos , Fígado/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Camundongos
2.
Environ Microbiol ; 23(6): 3077-3098, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33899316

RESUMO

Chronic respiratory diseases are part of accumulating health problems partly due to worldwide increase in air pollution. By their antimicrobial and immunomodulatory properties, some probiotics constitute promising alternatives for the prevention and treatment of chronic respiratory diseases. We have isolated Bacillus strains from Korean fermented foods and selected three potentially probiotic strains (two Bacillus subtilis and one Bacillus amyloliquefaciens) based on safety, antimicrobial efficacy, activity against airborne pathogens and their immunomodulatory properties in vivo. Safety evaluation included in silico analysis for confirming absence of virulence genes. Safety for the respiratory tract was confirmed by an in vivo pathogenicity test using a murine model. Antimicrobial activity was displayed against several airborne pathogens. Potential antimicrobial metabolites such as 2,3-butanediol and propylene glycol were identified as possible antagonistic agents. Immunomodulatory properties in vitro were confirmed by upregulation of IL-10 expression in a macrophage cell line. Intranasal instillation and inhalation in an ovalbumin (OVA)-induced lung inflammation murine model reduced T helper type 2 (Th2) cytokines at transcriptional and protein levels in the lungs. The safety and potentially beneficial role of these Bacillus strains could be demonstrated for the respiratory tract of a murine model.


Assuntos
Bacillus amyloliquefaciens , Bacillus , Probióticos , Animais , Anti-Inflamatórios , Bacillus/genética , Camundongos , Sistema Respiratório
3.
Int J Syst Evol Microbiol ; 69(5): 1521-1523, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30896384

RESUMO

The meeting of International Committee on Systematics of Prokaryotes, Subcommittee on the taxonomy of Bifidobacterium,Lactobacillus and related organisms was held within the frame of the FoodMicro 2018 Congress (FoodMicro 2018, 3-6 September 2018, Berlin, Germany). The meeting comprised an open session with a workshop entitled 'Modern approaches of LAB identification and conservation' and a closed session on issues related to ICSP Subcommittee activities.


Assuntos
Terminologia como Assunto , Berlim , Bifidobacterium/classificação , Congressos como Assunto , Lactobacillus/classificação
4.
Int J Syst Evol Microbiol ; 69(7): 2172-2173, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30896387

RESUMO

The meeting of International Committee on Systematics of Prokaryotes, Subcommittee on the taxonomy of Bifidobacterium, Lactobacillus and related organisms was held within the frame of the FoodMicro 2016 Congress in Dublin (FoodMicro 2016, 19-22 July 2016, Dublin, Ireland). The meeting comprised an open session with a workshop entitled 'Research and networking taxonomy in food with an emphasis on LAB' and a closed session on issues related to ICSP Subcommittee activities.

6.
Diabetes Obes Metab ; 20(7): 1688-1701, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29516607

RESUMO

AIMS: Although peroxisome proliferator-activated receptors (PPARs)α/γ dual agonists can be beneficial for treatment of dyslipidemia in patients with type 2 diabetes, their use is limited owing to various side effects, including body weight gain, edema, and heart failure. We aimed to demonstrate that amodiaquine, an antimalarial agent, has potential as a PPARα/γ dual agonist with low risk of adverse effects. METHODS: We screened a Prestwick library (Prestwick Chemical; Illkirch, France) to identify novel PPARα/γ dual agonists and selected amodiaquine (4-[(7-chloroquinolin-4-yl)amino]-2-[(diethylamino)methyl]phenol), which activated both PPAR-α & -γ, for further investigation. We performed both in vitro, including glucose uptake assay and fatty acid oxidation assay, and in vivo studies to elucidate the anti-diabetic and anti-obesity effects of amodiaquine. RESULTS: Amodiaquine selectively activated the transcriptional activities of PPARα/γ and enhanced both fatty acid oxidation and glucose uptake without altering insulin secretion in vitro. In high-fat diet-induced obese and genetically modified obese/diabetic mice, amodiaquine not only remarkably ameliorated insulin resistance, hyperlipidemia, and fatty liver but also decreased body weight gain. CONCLUSION: Our findings suggest that amodiaquine exerts beneficial effects on glucose and lipid metabolism by concurrent activation of PPARα/γ. Furthermore, amodiaquine acts as an alternative insulin-sensitizing agent with a positive influence on lipid metabolism and has potential to prevent and treat type 2 diabetes while reducing the risk of lipid abnormalities.


Assuntos
Amodiaquina/farmacologia , Antimaláricos/farmacologia , Glicemia/efeitos dos fármacos , Resistência à Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , PPAR alfa/agonistas , PPAR gama/agonistas , Células 3T3-L1 , Animais , Glicemia/metabolismo , Peso Corporal , Proliferação de Células , Dieta Hiperlipídica , Modelos Animais de Doenças , Ácidos Graxos/metabolismo , Fígado Gorduroso , Hiperlipidemias , Técnicas In Vitro , Fígado/metabolismo , Camundongos , Camundongos Obesos , Oxirredução , Triglicerídeos/metabolismo
7.
Appl Microbiol Biotechnol ; 101(4): 1605-1614, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27858139

RESUMO

The functional features of Lactobacillus plantarum HAC01 (HAC01), isolated from fermented Korean kimchi, were studied with regard to the fat mass, immunometabolic biomarkers and dysbiosis in a diet-induced obesity (DIO) murine model. L. rhamnosus GG (LGG) served as reference strain and a PBS-treated group as control. The administration of L. plantarum HAC01 resulted in reduction of the mesenteric adipose depot, the conjunctive tissue closely associated with the gastrointestinal tract, where lipid oxidative gene expression was upregulated compared to the control group. Metagenome analysis of intestinal microbiota showed that both strains HAC01 and LGG influenced specific bacterial families such as the Lachnospiraceae and Ruminococcaceae rather than the phyla Firmicutes and Bacteroidetes as a whole. The relative abundance of the Lachnospiraceae (phylum Firmicutes) was significantly higher in both LAB-treated groups than in the control. Comparing the impact of the two Lactobacillus strains on microbial composition in the gut also suggests strain-specific effects. The study emphasises the need for deeper studies into functional specificity of a probiotic organism at the strain level. Alleviation of obesity-associated dysbiosis by modulation of the gut microbiota appears to be associated with "indicator" bacterial taxa such as the family Lachnospiraceae. This may provide further insight into mechanisms basic to the mode of probiotic action against obesity and associated dysbiosis.


Assuntos
Tecido Adiposo/metabolismo , Microbioma Gastrointestinal/fisiologia , Lactobacillus plantarum/fisiologia , Obesidade/metabolismo , Obesidade/microbiologia , Animais , Dieta Hiperlipídica/efeitos adversos , Camundongos , Obesidade/etiologia
9.
Fish Shellfish Immunol ; 42(1): 177-83, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25449382

RESUMO

The effects of a dietary probiotic mixture containing Lactococcus (Lc.) lactis BFE920 isolated from bean sprout and autochthonous Lactobacillus (Lb.) plantarum FGL0001 originally isolated from the hindgut of olive flounder (Paralichthys olivaceus) were investigated for the purpose of improving the probiotic effects of Lc. lactis BFE920 on the olive flounder. The immunostimulatory, disease protective, and weight gain effects of Lc. lactis BFE920 were significantly improved when olive flounder (average weight 37.5±1.26 g) were fed the probiotic mixture (log10 7.0 CFU each/g feed pellet) for 30 days. Flounder fed the mixture showed improved skin mucus lysozyme activity and phagocytic activity of innate immune cells compared to flounder fed a single probiotic agent or a control diet. While the levels of neutrophil activity in flounder fed the single probiotic agent or the mixture were similar, they were significantly higher than levels in a control group. Additionally, probiotic-fed flounder showed significantly increased expressions of IL-6, IL-8, and TNF-α in the intestine compared to the control group. Following a 30-day period of being fed probiotics or a control diet, the olive flounder were challenged with an i.p. injection of Streptococcus iniae (log10 6.0 CFU/fish). The groups fed the mixed probiotics, Lc. lactis BFE920, Lb. plantarum FGL0001, and the control diet had survival rates of 55%, 45%, 35%, and 20%, respectively. Flounder fed the probiotic mixture gained 38.1±2.8% more body weight compared to flounder fed the control diet during the 30-day study period. These data strongly suggest that a mixture of Lc. lactis BFE920 and Lb. plantarum FGL0001 may serve as an immunostimulating feed additive useful for disease protection in the fish farming industry.


Assuntos
Adjuvantes Imunológicos/farmacologia , Resistência à Doença/efeitos dos fármacos , Linguado/imunologia , Imunidade Inata/efeitos dos fármacos , Probióticos/farmacologia , Animais , Citocinas/imunologia , Suplementos Nutricionais , Lactobacillus plantarum , Lactococcus lactis , Nitroazul de Tetrazólio , Fagocitose/imunologia , Análise de Sobrevida
11.
Fish Shellfish Immunol ; 35(5): 1585-90, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24041843

RESUMO

The protective effect of a food-grade lactic acid bacterium Lactococcus lactis BFE920 against disease of olive flounder (Paralichthys olivaceus) cultivated on a large scale was studied. Initially, antimicrobial activity of L. lactis against several fish pathogens was evaluated in vitro; the probiotic showed strong antibacterial activity against Streptococcus iniae, Streptococcus parauberis and Enterococcus viikkiensis, and moderate activity against Lactococcus garviae. When olive flounders were fed for two weeks with experimental diets containing varying concentrations of L. lactis (1 × 10(6), 5 × 10(6), 2.5 × 10(7) and 1.25 × 10(8) CFU/g feed), all the experimental feed groups showed 68-77% survival upon challenge with S. iniae. A field-scale feeding trial with L. lactis dietary supplement was conducted in a local fish farm (n = 12,000) for three months, and disease resistance, innate immune parameters and growth performance were evaluated. The average weight gain and feed efficiency were increased up to 6.8% and 8.5%, respectively. At the end of the feeding trial, the olive flounders were challenged with S. iniae. The L. lactis-fed group was protected from S. iniae challenge with a 66% survival rate. This disease protection is due to the flounder's innate immunity activated by the L. lactis administration: increased lysosomal activities and production of IL-12 and IFN-γ. These data clearly indicated that L. lactis BFE920 may be developed as a functional feed additive for protection against diseases, and for enhancement of feed efficiency and weight gain in olive flounder farming.


Assuntos
Doenças dos Peixes/imunologia , Doenças dos Peixes/prevenção & controle , Linguado , Imunidade Inata/imunologia , Lactococcus lactis , Probióticos/farmacologia , Infecções Estreptocócicas/veterinária , Animais , Aquicultura/métodos , Primers do DNA/genética , Suplementos Nutricionais , Imunidade Inata/efeitos dos fármacos , Nitroazul de Tetrazólio , Probióticos/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/prevenção & controle , Aumento de Peso/efeitos dos fármacos , Aumento de Peso/fisiologia
12.
PLoS One ; 18(2): e0280850, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36735734

RESUMO

Hepatobiliary abnormality and metabolic disorders are frequently observed complications in patients with inflammatory bowel diseases (IBD). Given that microbiota dysbiosis is a common pathophysiological feature of both IBD and metabolic diseases, we examined how the IBD-induced dysbiosis affects the host metabolism and contributes to the development of associated metabolic diseases using germ-free (GF) mice transplanted with fecal microbiota of DSS-induced colitis mice. There was no significant change in inflammation or barrier integrity in the gut of GF mice that received microbiota from colitis mice compared to their counterparts that were transplanted with microbiota from non-colitis healthy mice. Interestingly, it was observed that the GF recipients of colitis-induced altered microbiota showed a significant decrease in the weight of adipose tissues including mesenteric, epididymal, subcutaneous, and brown fat without any change in body weight, which was accompanied by abnormalities in adipose tissue functions such as fat storage and adiponectin production. Transplantation of colitis-induced altered microbiota also disrupted hepatic lipid metabolism in the GF recipient mice, which was observed by increases in synthesis and accumulation of cholesterol and bile acids in hepatocytes and a decrease in plasma HDL-cholesterol. Additional observations including elevated plasma levels of insulin, decreased hepatic production of FGF21, and decreased levels of fecal short chain fatty acids (SCFAs) and hepatic expression of SCFA receptors led to a conclusion that the transplantation of the colitis-associated dysbiotic microbiota was causally associated with impairments of insulin action and FGF21-adiponectin axis, possibly due to the low SCFA-producing capacity of the colonized microbiota, leading to metabolic abnormalities including adipose tissue dysfunction and dysregulated hepatic lipid metabolism. Our findings suggest potential mechanisms that explain how colitis-associated gut dysbiosis may contribute to the development of metabolic dysfunctions, which could be applied to clinical practice to improve the efficacy of treatment of IBD patients with comorbid metabolic disorders or vice versa.


Assuntos
Colite , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Insulinas , Animais , Camundongos , Adiponectina/metabolismo , Colesterol , Colite/induzido quimicamente , Colite/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Disbiose , Microbioma Gastrointestinal/fisiologia , Metabolismo dos Lipídeos , Camundongos Endogâmicos C57BL
13.
Front Microbiol ; 14: 1292266, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38449878

RESUMO

Introduction: Allergic airway diseases are one of the serious health problems in worldwide and allergic airway inflammation is a prerequisite led to the exacerbated situation such as mucus hypersecretion, epithelial barrier damage and microbiota dysbiosis. Because of side effects and low efficiencies of current therapeutics, the need for novel alternatives has been urged. Probiotics in which have diverse and beneficial modulatory effects have been applied to the airway inflammation model and the underlying mechanism needs to be investigated. Methods: We aimed to evaluate whether our target strain, Lactiplantibacillus plantarum APsulloc331261 (GTB1TM) isolated from green tea, can ameliorate allergic airway inflammation in mice and to figure out the mechanism. We induced allergic airway inflammation to mice by ovalbumin (OVA) and administered GTB1 orally and the immune and epithelial barrier markers were assessed. The gut metabolite and microbiota were also analysed, and the in vitro cell-line experiment was introduced to confirm the hypothesis of the study. Results: GTB1 ameliorated type 2 inflammation and suppressed mucin hypersecretion with the inhibition of MUC5AC in inflamed mice. Moreover, GTB1 increased the butyrate production and the relative abundance of butyrate producer, Clostridium cluster IV. We assumed that butyrate may have a potential role and investigated the effect of butyrate in mucin regulation via human airway epithelial cell line, A549. Butyrate significantly reduced the gene expression of MUC5AC in A549 cells suggesting its regulatory role in mucus production. Conclusion: Therefore, our study demonstrates that the oral administration of GTB1 can ameliorate allergic airway inflammation and mucin hypersecretion by butyrate production.

14.
Probiotics Antimicrob Proteins ; 15(3): 451-459, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-34647241

RESUMO

The functional characteristics of Lactobacillus johnsonii BFE6154, first isolated from Maasai traditional fermented milk, were previously identified in vitro, but its cholesterol-lowering properties have not been verified yet. In this study, we investigated the effect of L. johnsonii BFE6154 on cholesterol regulation and the mode of action. Stimulation of Caco-2 intestinal epithelial cells with L. johnsonii BFE6154 downregulated the gene expression of Niemann-Pick C1-like 1 (NPC1L1) through the activation of liver X receptor (LXR). Also, stimulation of HepG2 cells with the metabolites produced by L. johnsonii BFE6154 revealed an increase in the gene expression of low-density lipoprotein receptor (LDLR). Oral administration of L. johnsonii BFE6154 in mice receiving a high-fat and high-cholesterol diet (HFHCD), reduced total cholesterol and low-density lipoprotein-cholesterol (LDL) and increased high-density lipoprotein-cholesterol (HDL) in the blood, compared to the control. Diet-induced hypercholesterolemic mice receiving L. johnsonii BFE6154 showed a suppression of cholesterol absorption under the control of NPC1L1 in the intestine. Furthermore, L. johnsonii BFE6154 consumption ameliorated the hepatic cholesterol level and LDLR expression, which was reduced by HFHCD. These molecular modulations led to the increase of cholesterol excretion and the decrease of cholesterol levels in the feces and liver, respectively. Taken together, these results suggest that L. johnsonii BFE6154 may protect against diet-induced hypercholesterolemia through the regulation of cholesterol metabolism in the intestine and liver.


Assuntos
Hipercolesterolemia , Lactobacillus johnsonii , Humanos , Camundongos , Animais , Hipercolesterolemia/etiologia , Hipercolesterolemia/terapia , Células CACO-2 , Proteínas de Membrana Transportadoras/metabolismo , Colesterol , Dieta , LDL-Colesterol/metabolismo
15.
Sci Rep ; 13(1): 17918, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37864021

RESUMO

Mucosal tissues serve as the first defense line and their commensal microbiota play a role in sustaining of host health. This study aimed to isolate and evaluate a putative probiotic strain on various mucosal regions. Lactobacillus sakei HEM 224 was isolated from traditional Korean kimchi and identified. In the safety assessment L. sakei HEM 224 showed negative results for hemolysis, biogenic amine production and transferable antibiotic resistance. The probiotic potential of strain HEM 224 in diverse mucosal areas was shown in two different models, viz. a murine model with colitis induced by dextran sulfate sodium (DSS) and an allergic airway inflammation model induced by ovalbumin (OVA). In the colitis model, oral administration of L. sakei HEM 224 improved colitis physiology with immunomodulation, enhancing barrier components and gut microbiota alteration. In the allergic airway inflammation model, the intranasal administration of the strain decreased type 2 inflammation and enhanced epithelial barrier integrity from the airways. These results demonstrate that L. sakei HEM 224 can ameliorate inflammatory conditions in both the gastrointestinal and respiratory tracts through the reinforcement of the epithelial barrier and immunomodulation.


Assuntos
Colite , Latilactobacillus sakei , Probióticos , Humanos , Camundongos , Animais , Inflamação , Colite/induzido quimicamente , Colite/terapia , Sistema Respiratório , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Colo , Camundongos Endogâmicos C57BL
16.
J Bacteriol ; 193(20): 5868, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21952542

RESUMO

Weissella thailandensis fsh4-2 is a heterofermentative lactic acid bacterium isolated from the Korean fermented seafood condiment jeotkal. Here we report the draft genome sequence of W. thailandensis fsh4-2 (1,651 genes, 1,436 encoding known proteins, 183 encoding unknown proteins, 32 RNA genes), which consists of 50 large contigs of >100 bp.


Assuntos
Produtos Pesqueiros/microbiologia , Genoma Bacteriano , Weissella/genética , Sequência de Bases , Dados de Sequência Molecular , Weissella/isolamento & purificação
17.
Probiotics Antimicrob Proteins ; 13(1): 60-71, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32607730

RESUMO

Unveiling and understanding differences in physiological features below the species level may serve as an essential fast-screening tool for selecting strains that can promote a specific probiotic effect. To study the intra-species diversity of Bacillus, a genus with a wide range of enzyme activities and specificity, 190 Bacillus strains were isolated from traditional Korean fermented food products. Altogether, in the preliminary safety screening, 8 of these strains were found negative for lecithinase and hemolysis activity and were selected for further investigations. On the basis of different levels of enzyme functionalities (high or low proteolytic, amylolytic, and lipolytic (PAL) activities), two Bacillus subtilis strains were selected for an in vivo study. Each of the two strains was separately administered at a level of 1 × 108 CFU per day to C57BL/6 mice that were fed 60% high-fat diet ad libitum for 8 weeks, while Xenical, an anti-obesity drug, was used as a positive control in the experimental setup. B. subtilis M34 and B. subtilis GS40a with low and high amylolytic activities, respectively, induced significantly different and contrasting physiological effects. The production of short-chain fatty acids appeared to be closely associated with a shift in the gut microbiota.


Assuntos
Bacillus subtilis/isolamento & purificação , Dieta Hiperlipídica/efeitos adversos , Alimentos Fermentados/microbiologia , Microbioma Gastrointestinal , Obesidade , Probióticos , Segurança , Animais , Bacillus subtilis/classificação , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/induzido quimicamente , Obesidade/metabolismo , Obesidade/microbiologia , Obesidade/terapia , Probióticos/isolamento & purificação , Probióticos/farmacologia , República da Coreia
18.
J Food Prot ; 73(5): 870-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20501038

RESUMO

The diversity of Bacillus species isolated from the fermented soup condiment okpehe in Nigeria was studied using a combination of phenotypic and genotypic methods. Fifty strains presumptively characterized as Bacillus spp. using the API 50 CHB test were further identified by PCR of randomly amplified polymorphic DNA (RAPD) and by amplified ribosomal DNA restriction analysis (ARDRA) genotyping methods. ARDRA fingerprinting with HhaI, HinfI, and Sau3AI restriction enzymes did not allow successful differentiation between the Bacillus species, except for distinguishing B. cereus from other Bacillus species. This problem was overcome with the combination of RAPD PCR and ARDRA genotypic fingerprinting techniques. Sequencing of 16S rRNA genes of selected strains representative of the major clusters revealed that the Bacillus strains associated with this fermentation were B. subtilis, B. amyloliquefaciens, B. cereus, and B. licheniformis (in decreasing order of incidence). The presence of enterotoxin genes in all B. cereus strains was demonstrated by multiplex PCR. The high incidence of detection (20%) of possibly pathogenic B. cereus strains that contained enterotoxin genes indicated that these fermented foods may constitute a potential health risk.


Assuntos
Bacillus/genética , Condimentos/microbiologia , DNA Bacteriano/análise , Microbiologia de Alimentos , Bacillus/classificação , Cromossomos Bacterianos/genética , Impressões Digitais de DNA , Fermentação , Genes Bacterianos/genética , Variação Genética , Genótipo , Dados de Sequência Molecular , Nigéria , Fenótipo , Filogenia , RNA Ribossômico 16S/análise , Técnica de Amplificação ao Acaso de DNA Polimórfico , Especificidade da Espécie
19.
Food Microbiol ; 27(6): 757-68, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20630317

RESUMO

The diversity of lactic acid bacteria associated with Hussuwa fermentation, a Sudanese fermented sorghum food, was studied using a polyphasic taxonomical approach. Predominant strains could be well characterised based on a combination of phenotypic tests and genotypic methods such as ARDRA, rep-PCR and RAPD-PCR, as well as 16S rRNA gene sequencing of representative strains. Thus, the majority (128 of 220, 58.3%) of strains exhibited phenotypic properties typical of heterofermentative lactobacilli and of these, 100 strains were characterised more closely using the genotyping methods. The majority (97/100) strains could be characterised as Lactobacillus fermentum strains. Seventy-two of 220 strains (32.7%) showed phenotypic properties that are characteristic of pediococci. Of 41 selected strains investigated by genotyping techniques, 38 (92.7%) could be characterised as Pediococcus acidilactici strains, while three (7.3%) could be characterised as Pediococcus pentosaceus strains. The Hussuwa fermentation thus appears to be dominated by L. fermentum strains and P. acidilactici strains. For this reason, we selected representative and predominant strains as potential starter cultures for Hussuwa fermentation. These strains, L. fermentum strains BFE 2442 and BFE 2282 and P. acidilactici strain BFE 2300, were shown on the basis of RAPD-PCR fingerprinting to predominate in a model fermentation when used as starter cultures inoculated at 1 x 10(6) CFU/g and to lower the pH of the fermentation to below pH 4.0 within 48 h. These cultures should be studied for further development as starter preparations in pilot scale studies in actual field fermentations.


Assuntos
Fermentação , Lactobacillus/crescimento & desenvolvimento , Pediococcus/crescimento & desenvolvimento , Sorghum/microbiologia , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Genótipo , Humanos , Lactobacillus/classificação , Lactobacillus/genética , Lactobacillus/metabolismo , Pediococcus/classificação , Pediococcus/genética , Pediococcus/metabolismo , Filogenia , RNA Bacteriano , RNA Ribossômico 16S , Técnica de Amplificação ao Acaso de DNA Polimórfico
20.
Microorganisms ; 8(10)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32992853

RESUMO

The bacteriocin-producing strain Enterococcus faecium ST10Bz, isolated from boza, a Bulgarian cereal-based beverage, exhibited strong activity against Listeria strains, vancomycin-resistant and other Enterococcus strains, but not against most of the other lactic acid bacteria (LAB) strains included in the test panel. Bacteriocin ST10Bz was proven as a stable antimicrobial, even after exposure to various environmental conditions, including varying pH values, temperatures, and commonly used chemicals in industry and laboratory practice. Bacteriocin activity against L. monocytogenes ATCC®15313™ was recorded at 25,600 AU/mL when the producer strain was cultured in MRS broth at 25 °C and 30 °C, and 19,200 AU/mL, when cultured at 37 °C. Additionally, bacteriocin ST10Bz exhibited bactericidal mode of action when added to actively growing cultures of L. monocytogenes ATCC®15313™ and Enterococcus faecalis 200A. E. faecium ST10Bz was susceptible to the antibiotics kanamycin, gentamycin, ampicillin, streptomycin, tylosin, chloramphenicol, clindamycin, tetracycline, and vancomycin; with no evidence for vanA, B, C, D, E, or G genes. PCR analysis of DNA from strain ST10Bz generated positive results for presence of some bacterial adhesion genes, including map, mub and ef-tu, as well as the gamma aminobutyric acid (GABA) production-related gene, gad. Under simulated gastrointestinal conditions in single and co-culture with L. monocytogenes ATCC®15313™ and E. faecalis 200A, E. faecium ST10Bz showed a high survival rate and the ability to reduce the viable numbers of the two test strains.

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