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1.
J Sci Food Agric ; 100(4): 1822-1826, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31858597

RESUMO

BACKGROUND: Koumiss is a traditional fermented beverage made from mare's milk. The traditional backslopping method for koumiss production has shortcomings in terms of microbiological diversity and nutritional characteristics. In this study, a two-stage fermentation method was established to scale up the production of koumiss powder. The chemical composition and nutritional properties of a novel two-stage fermentation koumiss powder (TKP) were compared with backslopping koumiss powder (BKP). RESULTS: The TKP exhibited important nutritional and functional properties, including a high percentage of essential amino acids, and high polyunsaturated fatty acid, vitamin, and mineral content. The essential amino acid content of TKP was not significantly different from that of BKP. The oleic acid, linoleic acid, linolenic acid, and water-soluble vitamin content of TKP was higher than that of BKP. The Ca:P ratio of TKP was also close to the optimal Ca:P ratio in humans. CONCLUSION: The novel method could be applied for the scaled-up production of koumiss powder with similar nutritional properties to traditional backslopping koumiss powder. The successful production of koumiss powder could also promote the development of the koumiss industry. © 2019 Society of Chemical Industry.


Assuntos
Microbiologia de Alimentos/métodos , Kumis/análise , Leite/microbiologia , Pós/química , Aminoácidos/análise , Animais , Fermentação , Cavalos , Kumis/microbiologia , Lactobacillaceae/metabolismo , Leite/química , Minerais/análise , Valor Nutritivo , Vitaminas/análise
2.
Int J Food Microbiol ; 313: 108384, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31670259

RESUMO

Aiming at meeting the recommendations of the World Health Organization regarding the total fiber daily intake, an integrate biotechnological approach, combining xylanase treatment and lactic acid bacteria fermentation of milling by-products from pigmented wheat varieties, hull-less barley and emmer was proposed. The effects on the biochemical and nutritional features were investigated. Enhanced radical scavenging activity, increased concentrations of free amino acids (up to three times) and peptides and optimal in vitro protein digestibility (up to ca. 87%) value as well as relevant phytic acid degradation were achieved during bran fermentation. The main nutritional features of each matrix were enhanced and distinguished. Fortified breads were characterized by a concentration in total dietary fibers and protein of ca. 7 and 13% of dry matter, respectively. Compared to wheat bread the addition of pre-fermented brans caused a significant increase in protein digestibility (up to 79%), and a relevant decrease of the predicted glycemic index (ca. 8%) of the fortified bread. According to the results, this study demonstrates the potential of xylanase treatment and lactic acid bacteria fermentation to be used as suitable strategy to include bran in breadmaking, meeting both nutritional and sensory requests of modern consumers.


Assuntos
Pão/análise , Fibras na Dieta/análise , Endo-1,4-beta-Xilanases/química , Hordeum/microbiologia , Lactobacillales/metabolismo , Triticum/microbiologia , Biocatálise , Pão/microbiologia , Fibras na Dieta/metabolismo , Fermentação , Farinha/análise , Farinha/microbiologia , Aditivos Alimentares/análise , Aditivos Alimentares/metabolismo , Humanos , Lactobacillaceae/metabolismo , Valor Nutritivo , Ácido Fítico/análise , Ácido Fítico/metabolismo , Triticum/química , Resíduos/análise
3.
J Nutr ; 149(7): 1107-1115, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31162575

RESUMO

BACKGROUND: A link between high-fat diet consumption and obesity-related diseases is the disruption of the gut bacterial population, which promotes local and systemic inflammation. Wheat germ (WG) is rich in bioactive components with antioxidant and anti-inflammatory properties. OBJECTIVE: The aim of this study was to investigate the effects of WG supplementation in modulating the gut bacterial population and local and systemic inflammatory markers of mice fed a high-fat, high-sucrose (HFS) diet. METHODS: Six-week-old male C57BL/6 mice were randomly assigned to 4 groups (n = 12/group) and fed a control (C; 10% kcal fat, 10% kcal sucrose) or HFS (60% kcal fat, 20% kcal sucrose) diet with or without 10% WG (wt:wt) for 12 wk. Cecal bacteria was assessed via 16S rDNA sequencing, fecal short-chain fatty acids by GC, small intestinal CD4+ lymphocytes using flow cytometry, and gut antimicrobial peptide genes and inflammatory markers by quantitative polymerase chain reaction. Statistical analyses included Kruskal-Wallis/Dunn's test and 2-factor ANOVA using HFS and WG as factors. RESULTS: There was a 4-fold increase (P = 0.007) in the beneficial bacterial family, Lactobacillaceae, in the HFS + WG compared with the HFS group. Fecal propionic and n-butyric acids were elevated at least 2-fold in C + WG compared with the other groups (P < 0.0001). WG tended to increase (≥7%; P-trend = 0.12) small intestinal regulatory T cell:Th17 ratio, indicating a potential to induce an anti-inflammatory gut environment. WG elevated (≥35%) ileal gene expression of the anti-inflammatory cytokine Il10 compared to the unsupplemented groups (P = 0.038). Ileal gene expression of the antimicrobial peptides Reg3b and Reg3g was upregulated (≥95%) in the HFS + WG compared with other groups (P ≤ 0.040). WG reduced serum concentrations of the pro-inflammatory cytokines, interleukin (IL)-1B, IL-6, interferon-γ, and tumor necrosis factor-α (≥17%; P ≤ 0.012). CONCLUSIONS: WG selectively increased gut Lactobacillaceae, upregulated ileal antimicrobial peptides, and attenuated circulating pro-inflammatory cytokines of C57BL/6 mice fed a HFS diet. These changes may be vital in preventing HFS diet-induced comorbidities.


Assuntos
Dieta Hiperlipídica , Sacarose na Dieta/administração & dosagem , Suplementos Nutricionais , Microbioma Gastrointestinal , Lactobacillaceae/metabolismo , Triticum , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Ácidos Graxos Voláteis/metabolismo , Mediadores da Inflamação/metabolismo , Interleucina-10/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Triticum/química
4.
Microbiology ; 165(7): 772-778, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31100055

RESUMO

To investigate the metabolism of 18:2n-6 and 18:3n-3 by pure cultures of Sharpea azabuensis, two different strains (RL 1 and ST18) were each incubated in the presence of 40 µg ml-1 18:2n-6 or 18:3n-3. Pure cultures of Butyrivibriofibrisolvens D1 and Butyrivibrio proteoclasticus P18 were included as control treatments. Similar to the metabolism of B. fibrisolvens, both S. azabuensis strains converted 18:2n-6 or 18:3n-3 to cis-9, trans-11 CLA or cis-9, trans-11, cis-15 CLnA, after which it was further reduced to trans-11 18:1 or trans-11, cis-15 18:2, respectively. B. proteoclasticus additionally reduced trans-11 18:1 to 18:0. Trans-11, cis-15 18:2 was also further metabolized by B. proteoclasticus, although trans-11 18:1 did not accumulate, and only minor amounts of 18:0 were formed. The time frame of 18:2n-6 and 18:3n-3 biohydrogenation by S. azabuensis was comparable with B. fibrisolvens, indicating that S. azabuensis and B. fibrisolvens might be alternative biohydrogenators of 18:2n-6 and 18:3n-3 in the rumen.


Assuntos
Lactobacillaceae/metabolismo , Ácido Linoleico/metabolismo , Rúmen/microbiologia , Ácido alfa-Linoleico/metabolismo , Animais , Butyrivibrio/química , Butyrivibrio/genética , Butyrivibrio/metabolismo , Bovinos/microbiologia , Cavalos/microbiologia , Lactobacillaceae/química , Lactobacillaceae/genética , Ácido Linoleico/química , Estrutura Molecular , Ácido alfa-Linoleico/química
5.
Water Environ Res ; 91(7): 573-580, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30695123

RESUMO

The waste-free policy is part of the process of sugar production from beets in which the resulting molasses are used for ethanol production. However, during this process another byproduct, namely vinasse, is created. Therefore, there is a problem with the utilization of wastewater, which cannot be disposed to the environment without being treated. Melanoidins, caramels, and hexoses alkaline degradation products contained in the vinasse give it a dark brown color. The aim of the study was to investigate the effect of the pH and the temperature on the decolorization of vinasse by lactic acid bacteria (Lactobacillus plantarum, L. casei, and Pediococcus parvulus). Experiments were performed in batch mode in a BioStatB bioreactor for 72 hrs. The medium consisted of 25% v/v sugar beet molasses vinasse, 77.34 gdm-3 of glucose, and 2.24 gdm-3 of yeast extract. The maximum decolorization was 25.14% and was achieved at noncontrolled pH 6.5 and at 30°C. PRACTITIONER POINTS: Lactobacillus plantarum, L. casei and Pediococcus parvulus showed potential for decolorization of sugar beet molasses vinasse. Controlled pH has a negative effect on sugar beet molasses vinasse decolorization. Toxic substances, i.e. acrylamide, 4-methylimidazole , 5-hydroxymethylfurfural and furfural after decolorization was not detected. Bacteria showed high degradation potential of 2-acetyl-4-(1,2,3,4)-tetrahydroxy-butylimidazole.


Assuntos
Lactobacillaceae/metabolismo , Eliminação de Resíduos Líquidos/métodos , Cor , Concentração de Íons de Hidrogênio , Temperatura
6.
Food Microbiol ; 76: 267-278, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30166150

RESUMO

Mawè is a West African spontaneous fermented cereal-based dough. Different types of mawè exist varying in type of cereal and/or production condition, with fermentations lasting 24-48 h. With the aim of obtaining a comprehensive understanding of the microbial ecology of mawè processing, a microbiological characterisation was performed for four mawè types, produced at eight sites in Benin. At the onset of the fermentations lactic acid bacteria (LAB) and yeast counts were on average 7.5 ±â€¯1.03 and 4.8 ±â€¯0.79 Log10 cfu/g, which increased to 9.2 ±â€¯0.38 and 7.4 ±â€¯0.42 Log10 cfu/g, respectively, at the end of the fermentations. LAB (n = 321) and yeasts (n = 298), isolated during the fermentations, were identified. The predominant LAB and yeast species were Lactobacillus fermentum and Pichia kudriavzevii, respectively, followed by Kluyveromyces marxianus, all present throughout the mawè fermentations. Further, microbial successions took place with Weissella confusa occurring mostly at the onset, while Pediococcus acidilactici and Saccharomyces cerevisiae were mainly associated with the end of the fermentations. Species diversity was influenced both by type of cereal and production condition. The dominating strain clusters of L. fermentum and P. kudriavzevii were ubiquitous and strain diversities were influenced by type of cereal and production site.


Assuntos
Grão Comestível/microbiologia , Fermentação , Alimentos e Bebidas Fermentados/microbiologia , Lactobacillaceae/isolamento & purificação , Leveduras/isolamento & purificação , Candida/isolamento & purificação , Candida/metabolismo , Microbiologia de Alimentos , Ácido Láctico/análise , Lactobacillaceae/classificação , Lactobacillaceae/metabolismo , Lactobacillus fermentum/isolamento & purificação , Pichia/isolamento & purificação , Pichia/metabolismo , Saccharomyces cerevisiae/isolamento & purificação , Saccharomyces cerevisiae/metabolismo , Leveduras/classificação , Leveduras/metabolismo
7.
Nutrients ; 10(10)2018 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-30249054

RESUMO

The bioavailability of pollen bioactive compounds for humans is limited. In this study, our aim was to enhance the health-related benefits of pollen by fermentation with a Kombucha/SCOBY (symbiotic culture of bacteria and yeasts) consortium. We performed the fermentation of pollen suspended from the beginning with SCOBY on sweetened green tea or on Kombucha vinegar, by adding pollen after 20 days of Kombucha fermentation. We analyzed: formation of bioactive compounds (anti-oxidant polyphenols, soluble silicon, hydroxy-acids, short chain fatty acids-SCFA); parameters related to Kombucha fermentation (dynamics of lactic acid bacteria-LAB, formation of organic acids, soluble sugar evolution on Kombucha vinegar); the influence of Kombucha fermentation on pollen morphology and ultrastructure; in vitro cytotoxic and antitumoral effects of the Kombucha fermented pollen. The pollen addition increases LAB proportion in the total number of SCOBY microbial strains. SEM images highlight the adhesion of the SCOBY bacteria to pollen. Ultrastructural analysis reveals the release of the pollen content. The content of bioactive compounds (polyphenols, soluble silicon species and SCFA) is higher in the fermented pollen and the product shows a moderate antitumoral effect on Caco-2 cells. The health benefits of pollen are enhanced by fermentation with a Kombucha consortium.


Assuntos
Antioxidantes/metabolismo , Ácidos Graxos Voláteis/metabolismo , Chá de Kombucha , Lactobacillaceae/metabolismo , Pólen , Silício/metabolismo , Chá , Adenocarcinoma/prevenção & controle , Animais , Antineoplásicos/metabolismo , Aderência Bacteriana , Células CACO-2 , Linhagem Celular Tumoral , Neoplasias do Colo/prevenção & controle , Meios de Cultura , Composição de Medicamentos/métodos , Fermentação , Microbiologia de Alimentos , Humanos , Chá de Kombucha/microbiologia , Camundongos , Extratos Vegetais/metabolismo , Extratos Vegetais/uso terapêutico , Pólen/microbiologia , Pólen/ultraestrutura , Polifenóis/metabolismo , Açúcares/metabolismo , Chá/metabolismo , Chá/microbiologia , Leveduras/metabolismo
8.
Appl Environ Microbiol ; 84(21)2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30143505

RESUMO

In the present study, we investigated whether reducing the particle size of wheat bran affects the colonizing microbial community using batch fermentations with cecal inocula from seven different chickens. We also investigated the effect of in-feed administration of regular wheat bran (WB; 1,690 µm) and wheat bran with reduced particle size (WB280; 280 µm) on the cecal microbial community composition of broilers. During batch fermentation, WB280 was colonized by a lactic acid-producing community (Bifidobacteriaceae and Lactobacillaceae) and by Lachnospiraceae that contain lactic acid-consuming butyric acid-producing species. The relative abundances of the Enterobacteriaceae decreased in the particle-associated communities for both WB and WB280 compared to that of the control. In addition, the community attached to wheat bran was enriched in xylan-degrading bacteria. When administered as a feed additive to broilers, WB280 significantly increased the richness of the cecal microbiota and the abundance of bacteria containing the butyryl-coenzyme A (CoA):acetate CoA-transferase gene, a key gene involved in bacterial butyrate production, while decreasing the abundances of Enterobacteriaceae family members in the ceca. Particle size reduction of wheat bran thus resulted in the colonization of the bran particles by a very specific lactic acid- and butyric acid-producing community and can be used to steer toward beneficial microbial shifts. This can potentially increase the resilience against pathogens and increase animal performance when the reduced-particle-size wheat bran is administered as a feed additive to broilers.IMPORTANCE Prebiotic dietary fibers are known to improve the gastrointestinal health of both humans and animals in many different ways. They can increase the bulking capacity, improve transit times, and, depending on the fiber, even stimulate the growth and activity of resident beneficial bacteria. Wheat bran is a readily available by-product of flour processing and is a highly concentrated source of (in)soluble dietary fiber. The intake of fiber-rich diets has been associated with increased Firmicutes and decreased Proteobacteria numbers. Here, we show that applying only 1% of a relatively simple substrate which was technically modified using relatively simple techniques reduces the concentration of Enterobacteriaceae This could imply that in future intervention studies, one should take the particle size of dietary fibers into account.


Assuntos
Ração Animal/microbiologia , Galinhas/microbiologia , Fibras na Dieta/análise , Enterobacteriaceae/crescimento & desenvolvimento , Microbioma Gastrointestinal , Lactobacillaceae/crescimento & desenvolvimento , Ração Animal/análise , Animais , Ácido Butírico/metabolismo , Ceco/microbiologia , Galinhas/metabolismo , Fibras na Dieta/metabolismo , Fibras na Dieta/microbiologia , Fermentação , Ácido Láctico/metabolismo , Lactobacillaceae/metabolismo , Tamanho da Partícula , Triticum/química , Triticum/metabolismo , Triticum/microbiologia
9.
Cell Metab ; 27(6): 1222-1235.e6, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29874567

RESUMO

Multiple sclerosis (MS) is more common in western countries with diet being a potential contributing factor. Here we show that intermittent fasting (IF) ameliorated clinical course and pathology of the MS model, experimental autoimmune encephalomyelitis (EAE). IF led to increased gut bacteria richness, enrichment of the Lactobacillaceae, Bacteroidaceae, and Prevotellaceae families and enhanced antioxidative microbial metabolic pathways. IF altered T cells in the gut with a reduction of IL-17 producing T cells and an increase in regulatory T cells. Fecal microbiome transplantation from mice on IF ameliorated EAE in immunized recipient mice on a normal diet, suggesting that IF effects are at least partially mediated by the gut flora. In a pilot clinical trial in MS patients, intermittent energy restriction altered blood adipokines and the gut flora resembling protective changes observed in mice. In conclusion, IF has potent immunomodulatory effects that are at least partially mediated by the gut microbiome.


Assuntos
Autoimunidade , Sistema Nervoso Central/imunologia , Encefalomielite Autoimune Experimental , Jejum , Microbioma Gastrointestinal , Esclerose Múltipla , Adipocinas/sangue , Adulto , Animais , Bacteroidaceae/metabolismo , Encefalomielite Autoimune Experimental/dietoterapia , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/microbiologia , Feminino , Humanos , Lactobacillaceae/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Esclerose Múltipla/dietoterapia , Esclerose Múltipla/imunologia , Esclerose Múltipla/microbiologia , Projetos Piloto , Linfócitos T Reguladores/imunologia , Células Th17/imunologia
10.
Food Microbiol ; 70: 143-154, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29173621

RESUMO

Nicastrese goat's cheese is produced in the South of Italy under traditional procedures, from raw goat milk without any starter cultures addition. Samples from milk to ripened cheese provided by 4 different farms were subjected to a polyphasic approach to study their physico-chemical, microbiological and sensorial characteristics. In addition, volatile organic compounds formation in the final products was studied. Overall, gross composition and microbiological data revealed a significant variability among samples, which was confirmed by both the volatile organic compounds generated in the final products and by the sensorial data. Conventional technique allowed us to identify 720 isolates, mainly belonging to Lactococcus lactis, Lactobacillus plantarum, Lactobacillus casei, Lactobacillus brevis, Leuconostoc mesenteroides, and Enterococcus faecalis. Culture-independent methods revealed shifts in the microbial community structure, with an increase in biodiversity of metabolically active bacterial species, from milk to cheese samples. Analysis of volatile organic compounds (VOCs) allowed the identification of 36 compounds; free fatty acids and ketones represented the main detected, followed by alcohols and esters. Moreover, statistical analysis was performed in order to correlate VOCs to bacterial species. Data showed that ester compounds as well as alcohol and aldehydes were positively correlated to NSLAB, indicating that the occurrence of L. casei, L. plantarum and L. brevis species is relevant for the VOCs formation in the final product.


Assuntos
Queijo/microbiologia , Lactobacillaceae/isolamento & purificação , Animais , Biodiversidade , Queijo/análise , Fermentação , Cabras , Itália , Lactobacillaceae/classificação , Lactobacillaceae/genética , Lactobacillaceae/metabolismo , Leite/química , Leite/microbiologia , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
11.
J Sci Food Agric ; 98(1): 113-121, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28542883

RESUMO

BACKGROUND: Daqu is a fermentative saccharification agent that is used to initiate fermentation in the production of Chinese liquor and vinegar. This study investigated the differences of amylase, protease and esterase in dominance of different types of Daqu, which can be useful for quality control and flavor improvement of Daqu production by enzyme technology. RESULTS: Hydrolase activities in different Daqu samples were compared by principal component analysis (PCA). Based on protein electrophoresis and 1 H NMR spectroscopy, the protein patterns and metabolites in Daqu were further analysed. The results indicated that the highest amylase activities and diversities were found in low/medium-temperature of Daqu which had light-flavour and strong-flavour. Proteases play a significant role in determining the quality of high-temperature Daqu samples which had a sauce-flavour. Furthermore, the contributions of esterase to both strong and sauce flavour development in high-temperature Daqu are similar. CONCLUSION: Results from the present work showed that differences in amylase, protease and esterase play a leading role in different types of Daqu, which can be useful for quality control and technology development of Daqu. © 2017 Society of Chemical Industry.


Assuntos
Bebidas Alcoólicas/análise , Proteínas de Bactérias/análise , Hidrolases/análise , Lactobacillaceae/metabolismo , Bebidas Alcoólicas/microbiologia , Proteínas de Bactérias/metabolismo , China , Fermentação , Aromatizantes/análise , Aromatizantes/metabolismo , Hidrolases/metabolismo , Lactobacillaceae/enzimologia
12.
J Nutr ; 147(11): 2031-2040, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28954838

RESUMO

Background: Changes in whole-grain chemical composition can affect the site of nutrient digestion, which may alter substrate availability and gut microbiota composition.Objective: This study elucidated the function of whole-grain fermentable fiber composition on ileal substrate flow, hindgut substrate availability, and subsequent gut microbial profiles in pigs.Methods: Five whole grains-1) high-fermentability, high-ß-glucan hull-less barley (HFB); 2) high-fermentability, high-amylose hull-less barley (HFA); 3) moderate-fermentability hull-less barley (MFB); 4) low-fermentability hulled barley (LFB); or 5) low-fermentability hard red spring wheat (LFW)-were included at 800 g/kg into diets fed to ileal-cannulated growing pigs for 9 d in a 6 (periods) × 5 (diets) Youden square. Digesta were analyzed for nutrient flow and microbial composition via 16S ribosomal RNA gene sequencing.Results: The consumption of fermentable whole grains, HFB, and HFA increased (P < 0.05) ileal starch flow by 69% and dry matter flow by 37% compared with LFB and LFW intakes. The consumption of HFB and HFA increased (P < 0.05) fecal Firmicutes phylum abundance by 26% and 21% compared with LFB intake and increased (P < 0.05) fecal Dialister genus abundance, on average, by 98% compared with LFB and LFW intakes. Fecal Sharpea and Ruminococcus genera abundances increased (P < 0.05) with HFB intake compared with LFB and LFW intakes. In contrast, the consumption of LFB increased (P < 0.05) fecal Bacteroidetes phylum abundance by 43% compared with MFB intake. Ileal starch flow and fecal Firmicutes abundance were positively correlated and determined by using principal components analysis.Conclusions: Increasing dietary fermentable fiber from whole grains can increase ileal substrate flow and hindgut substrate availability, shifting the fecal microbiota toward Firmicutes phylum members. Thus, digesta substrate flow is important to shape gut microbial profiles in pigs, which indicates that the manipulation of substrate flow should be considered as a tool to modulate gut microbiota composition.


Assuntos
Fibras na Dieta/análise , Microbioma Gastrointestinal , Íleo/microbiologia , Amido/análise , Grãos Integrais/química , Amilose/administração & dosagem , Amilose/análise , Ração Animal , Animais , Dieta/veterinária , Fibras na Dieta/administração & dosagem , Fezes/química , Fezes/microbiologia , Fermentação , Firmicutes/isolamento & purificação , Firmicutes/metabolismo , Hordeum/química , Íleo/metabolismo , Lactobacillaceae/isolamento & purificação , Lactobacillaceae/metabolismo , Masculino , Análise de Componente Principal , RNA Ribossômico 16S/isolamento & purificação , Ruminococcus/isolamento & purificação , Ruminococcus/metabolismo , Amido/administração & dosagem , Suínos , Triticum/química , beta-Glucanas/administração & dosagem , beta-Glucanas/análise
13.
Appl Microbiol Biotechnol ; 101(19): 7409-7415, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28812142

RESUMO

Activated carbon (AC) is an increasingly attractive remediation alternative for the sequestration of dioxins at contaminated sites globally. However, the potential for AC to reduce the bioavailability of dioxins in mammals and the residing gut microbiota has received less attention. This question was partially answered in a recent study examining 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced hallmark toxic responses in mice administered with TCDD sequestered by AC or freely available in corn oil by oral gavage. Results from that study support the use of AC to significantly reduce the bioavailability of TCDD to the host. Herein, we examined the bioavailability of TCDD sequestered to AC on a key murine gut commensal and the influence of AC on the community structure of the gut microbiota. The analysis included qPCR to quantify the expression of segmented filamentous bacteria (SFB) in the mouse ileum, which has responded to TCDD-induced host toxicity in previous studies and community structure via sequencing the 16S ribosomal RNA (rRNA) gene. The expression of SFB 16S rRNA gene and functional genes significantly increased with TCDD administered with corn oil vehicle. Such a response was absent when TCDD was sequestered by AC. In addition, AC appeared to have a minimal influence on murine gut community structure and diversity, affecting only the relative abundance of Lactobacillaceae and two other groups. Results of this study further support the remedial use of AC for eliminating bioavailability of TCDD to host and subsequent influence on the gut microbiome.


Assuntos
Carvão Vegetal/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Dibenzodioxinas Policloradas/administração & dosagem , Animais , Disponibilidade Biológica , Carvão Vegetal/farmacocinética , Óleo de Milho/administração & dosagem , Óleo de Milho/farmacocinética , Feminino , Íleo/microbiologia , Lactobacillaceae/metabolismo , Camundongos , Dibenzodioxinas Policloradas/farmacocinética , Dibenzodioxinas Policloradas/toxicidade , RNA Ribossômico 16S/genética , Transcriptoma
14.
J Med Food ; 20(7): 637-645, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28598242

RESUMO

In this study, the antithrombotic and thrombolytic ability of second fermented extract of Ophiopogon japonicus (FEOJ) was verified in thrombosis-induced rats. Thrombosis was induced by oral administration of 2% carrageenan for 4 weeks. Five experimental groups (n = 9/group) involved in the study were control group, thrombosis group, low-dose FEOJ group (2 mL/kg, low-dose Ophiopogon japonicus [LOJ]), middle-dose FEOJ group (6 mL/kg, medium-dose Ophiopogon japonicus [MOJ]), and high-dose FEOJ group (12 mL/kg, high-dose Ophiopogon japonicus [HOJ]). The clotting time (CT), bleeding time (BT), prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen (FBG) were assessed in blood samples, and histological studies were performed on liver and lung tissues. The results demonstrated delayed CT only in MOJ and HOJ groups and delayed BT in all FEOJ groups compared with those in thrombosis and control groups (P < .05). Similarly, APTT was significantly delayed only in MOJ and HOJ groups, and PT was significantly delayed in all FEOJ groups, compared with those in control and thrombosis groups (P < .05). Although concentrations of FBG were similar in control, thrombosis, and LOJ groups, the tendency for decreased concentration of FBG (statistically nonsignificant) in MOJ and HOJ groups has been observed. Histological examination of livers and lungs revealed that thrombosis was partially improved in FEOJ group compared with the thrombosis group. In conclusion, CT, BT, PT, and APTT were prolonged in FEOJ group more than in control and thrombosis groups, thereby, depicting antithrombotic and thrombolytic effects. However, concentration-dependent effects of FEOJ were more prominent in MOJ and HOJ groups than in the LOJ group.


Assuntos
Anticoagulantes/administração & dosagem , Ophiopogon/química , Extratos Vegetais/administração & dosagem , Trombose/tratamento farmacológico , Animais , Anticoagulantes/isolamento & purificação , Anticoagulantes/metabolismo , Tempo de Sangramento , Coagulação Sanguínea/efeitos dos fármacos , Carragenina/efeitos adversos , Fermentação , Humanos , Lactobacillaceae/metabolismo , Masculino , Ophiopogon/microbiologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Tempo de Protrombina , Ratos , Ratos Sprague-Dawley , Trombose/sangue , Trombose/induzido quimicamente
15.
J Hazard Mater ; 336: 41-51, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28472707

RESUMO

Α novel two-phase bioreactor for the microbial removal of Cr(VI) from wastewater with high chromium concentration (up to 1350ppm) is developed. Among several potential solid-phase adsorbents tested, Cloisite® 30B, a natural montmorillonite modified with a quaternary ammonium salt that absorbs Cr(VI) in a reversible manner proved to be optimal as the solid phase of the bioreactor. Cloisite® 30B has no toxicity to the acclimated biomass and keeps the concentration of Cr(VI) ions at sub-inhibitory levels that ensure the efficient microbial removal of Cr(VI). The microbial removal of Cr(VI) was achieved using an acclimated mixed culture developed from anaerobic sludge. The novel bioreactor was operated as a Sequencing Batch Reactor (SBR) under anaerobic and mesophilic conditions for over 200 cycles, without further addition of the solid adsorbent, and led to even 100% removal of Cr(VI) with high removal rates for concentrations ranging from 900-1350mg/L Cr(VI). The reduction of Cr(VI) to the less toxic Cr(III) was proved to be mediated by lactate, generated by a lactic acid bacterium, 99% similar to Pediococcus acidilactici as demonstrated by molecular methods The reduction of Cr(VI) took place extracellularly where it reacts with the lactic acid produced during the process of glycolysis.


Assuntos
Reatores Biológicos , Cromo/isolamento & purificação , Lactobacillaceae/metabolismo , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Anaerobiose , Bentonita/química , Biodegradação Ambiental , Cromo/análise , DNA Bacteriano/genética , Glicólise , Ácido Láctico/biossíntese , Ácido Láctico/metabolismo , Lactobacillaceae/genética , Oxirredução , RNA Ribossômico 16S/genética , Esgotos , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise
16.
Trends Biotechnol ; 35(8): 756-769, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28549804

RESUMO

Lactic acid bacteria are well known to be beneficial for food production and, as probiotics, they are relevant for many aspects of health. However, their potential as cell factories for the chemical industry is only emerging. Many physiological traits of these microorganisms, evolved for optimal growth in their niche, are also valuable in an industrial context. Here, we illuminate these features and describe why the distinctive adaptation of lactic acid bacteria is particularly useful when developing a microbial process for chemical production from renewable resources. High carbon uptake rates with low biomass formation combined with strictly regulated simple metabolic pathways, leading to a limited number of metabolites, are among the key factors defining their success in both nature and industry.


Assuntos
Biotecnologia/métodos , Lactobacillaceae , Biomassa , Biotecnologia/tendências , Lactobacillaceae/genética , Lactobacillaceae/crescimento & desenvolvimento , Lactobacillaceae/metabolismo
17.
Adv Appl Microbiol ; 99: 1-51, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28438266

RESUMO

Two-component systems (TCSs) are widespread signal transduction pathways mainly found in bacteria where they play a major role in adaptation to changing environmental conditions. TCSs generally consist of sensor histidine kinases that autophosphorylate in response to a specific stimulus and subsequently transfer the phosphate group to their cognate response regulators thus modulating their activity, usually as transcriptional regulators. In this review we present the current knowledge on the physiological role of TCSs in species of the families Lactobacillaceae and Leuconostocaceae of the group of lactic acid bacteria (LAB). LAB are microorganisms of great relevance for health and food production as the group spans from starter organisms to pathogens. Whereas the role of TCSs in pathogenic LAB (most of them belonging to the family Streptococcaceae) has focused the attention, the roles of TCSs in commensal LAB, such as most species of Lactobacillaceae and Leuconostocaceae, have been somewhat neglected. However, evidence available indicates that TCSs are key players in the regulation of the physiology of these bacteria. The first studies in food-associated LAB showed the involvement of some TCSs in quorum sensing and production of bacteriocins, but subsequent studies have shown that TCSs participate in other physiological processes, such as stress response, regulation of nitrogen metabolism, regulation of malate metabolism, and resistance to antimicrobial peptides, among others.


Assuntos
Lactobacillaceae/metabolismo , Transdução de Sinais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bacteriocinas/metabolismo , Microbiologia de Alimentos , Histidina Quinase/genética , Histidina Quinase/metabolismo , Ácido Láctico/metabolismo , Lactobacillaceae/enzimologia , Lactobacillaceae/genética
18.
Food Microbiol ; 65: 95-104, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28400025

RESUMO

Buckwheat sourdoughs supplemented with molasses as natural sucrose source were fermented with levan-producing Gluconobacter (G.) albidus TMW 2.1191 and Kozakia (K.) baliensis NBRC 16680. Cell growth, concomitant levan and low-molecular-weight metabolite production were monitored. Sourdough breads were prepared with different sourdoughs from both strains (24, 30 and 48 h fermentation, respectively) and analyzed with respect to bread volume, crumb hardness and sensory characteristics. During fermentation, levan, acetic and gluconic acids were increasingly produced, while spontaneously co-growing lactic acid bacteria additionally formed acetic and lactic acids. Sourdoughs from both strains obtained upon 24 h of fermentation significantly improved the bread sensory and quality, including higher specific volume as well as lower crumb hardness. Buckwheat doughs containing isolated levan, with similar molecular size and mass compared to in situ produced levan in the sourdough at 48 h, verified the positive effect of levan on bread quality. However, the positive effects of levan were masked to a certain extent by the impact from the natural acidification during fermentations. While levan-producing acetic acid bacteria are a promising alternative for the development of clean-label gluten-free breads without the need of additives, an appropriate balance between acidification and levan production (amount and structure) must be reached.


Assuntos
Ácido Acético/metabolismo , Acetobacteraceae/metabolismo , Pão/microbiologia , Fagopyrum/microbiologia , Frutanos/biossíntese , Gluconobacter/metabolismo , Acetobacteraceae/crescimento & desenvolvimento , Antineoplásicos , Bactérias/metabolismo , Pão/análise , Fermentação , Farinha/microbiologia , Microbiologia de Alimentos , Frutanos/metabolismo , Gluconobacter/crescimento & desenvolvimento , Glutens , Lactobacillaceae/crescimento & desenvolvimento , Lactobacillaceae/metabolismo
19.
Int J Food Microbiol ; 241: 252-261, 2017 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-27810447

RESUMO

Lactic acid bacteria strains, previously isolated from the same matrix, were used to ferment quinoa flour aiming at exploiting the antioxidant potential. As in vitro determined on DPPH and ABTS radicals, the scavenging activity of water/salt-soluble extracts (WSE) from fermented doughs was significantly (P<0.05) higher than that of non-inoculated doughs. The highest inhibition of linoleic acid autoxidation was found for the quinoa dough fermented with Lactobacillus plantarum T0A10. The corresponding WSE was subjected to Reverse Phase Fast Protein Liquid Chromatography, and 32 fractions were collected and subjected to in vitro assays. The most active fraction was resistant to further hydrolysis by digestive enzymes. Five peptides, having sizes from 5 to 9 amino acid residues, were identified by nano-Liquid Chromatography-Electrospray Ionisation-Mass Spectra/Mass Spectra. The sequences shared compositional features which are typical of antioxidant peptides. As shown by determining cell viability and radical scavenging activity (MTT and DCFH-DA assays, respectively), the purified fraction showed antioxidant activity on human keratinocytes NCTC 2544 artificially subjected to oxidative stress. This study demonstrated the capacity of autochthonous lactic acid bacteria to release peptides with antioxidant activity through proteolysis of native quinoa proteins. Fermentation of the quinoa flour with a selected starter might be considered suitable for novel applications as functional food ingredient, dietary supplement or pharmaceutical preparations.


Assuntos
Antioxidantes/metabolismo , Chenopodium quinoa/microbiologia , Farinha/microbiologia , Lactobacillaceae/metabolismo , Antioxidantes/análise , Pão/microbiologia , Chenopodium quinoa/química , Chenopodium quinoa/metabolismo , Cromatografia Líquida de Alta Pressão , Fermentação , Farinha/análise , Humanos , Ácido Láctico/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Espectrometria de Massas por Ionização por Electrospray
20.
Appl Biochem Biotechnol ; 182(1): 142-154, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27844338

RESUMO

The colorimetric assay is phospholipid/polydiacetylene vesicle-based assay used for the detection of membrane-acting peptides. Bacteriocins and halocins are antimicrobial peptides known to kill target cells by membrane disruption. Therefore, the assay was applied for high-throughput (HTP) screening of bacteriocins and halocins produced by lactic acid bacteria and haloarchaea, respectively. The assay consisted of vesicles which were synthesized using four different phospholipids: dipalmitoylphosphatydilcholine (DPPC), dimyristoylphosphatidylcholine (DMPC), dimyristoylphosphoethanolamine (DMPE) and dimyristoylphosphatidylglycerol (DMPG) in combination with diacetylene monomer 10,12-tricosadiy noic acid (TRCDA). These vesicles demonstrated blue colour at 640 nm and turned pink/red after interaction with nisin. DMPE/TRCDA vesicles showed pink colour with the highest colorimetric response (CR %) after treatment with nisin and, therefore, selected for the screening of bacteriocins and halocins. The colour of the vesicles was changed within 5 min in the presence of 5 µM nisin suggesting the sensitivity of assay. The assay was applied on 54 strains of lactic acid bacteria (LAB) and 53 haloarchaea for screening of bacteriocins and halocins, respectively. Out of these strains, three strains of LAB and five strains of haloarchaea were found to be bacteriocin and halocin non-producer, respectively. The other strains demonstrated the presence of bacteriocins and halocins. The colorimetric assay was found to be rapid, specific and reliable for HTP screening of antimicrobial peptides such as bacteriocins and halocins from producer strains isolated from various natural resources.


Assuntos
Bacteriocinas/análise , Colorimetria/métodos , Halobacteriaceae/metabolismo , Ensaios de Triagem em Larga Escala , Lactobacillaceae/metabolismo , Peptídeos/análise , 1,2-Dipalmitoilfosfatidilcolina/química , Peptídeos Catiônicos Antimicrobianos , Bacteriocinas/biossíntese , Dimiristoilfosfatidilcolina/química , Ácidos Graxos Insaturados/química , Halobacteriaceae/química , Lactobacillaceae/química , Peptídeos/metabolismo , Fosfatidiletanolaminas/química , Fosfatidilgliceróis/química
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