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1.
Food Microbiol ; 86: 103348, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31703879

RESUMO

The effects of the incorporation of the essential oils from Origanum vulgare L. (OVEO; 0.07 µL/g) and Rosmarinus officinalis L. (ROEO; 2.65 µL/g) in combination in Minas Frescal cheese on the counts of the probiotic Lactobacillus acidophilus LA-5 and Escherichia coli O157:H7 were evaluated during refrigerated storage (7 ±â€¯0.5 °C). The terpenes of OVEO and ROEO, survival of the probiotic strain during in vitro digestion, as well as the physicochemical and sensory aspects were also monitored in Minas Frescal cheese. All terpenes decreased in cheese when the storage time increased. The incorporation of OVEO and ROEO delayed the increase in L. acidophilus LA-5 counts in cheese, but did not affect its ability to survive in cheese under simulated gastrointestinal conditions. The decreases in counts of E. coli O157:H7 observed in the first 15 days of refrigerated storage were strongly correlated (r ≥ 0.82) with the terpenes detected in cheese. Scores attributed for aroma, flavor, overall impression and purchase intention of cheese with OVEO and ROEO increased with the increase of the storage time. The incorporation of OVEO and ROEO in combination could be a strategy to control E. coli O157:H7 in probiotic Minas cheese during storage; however, the amounts of these substances should be cautiously selected considering possible negative sensory impacts in this product.


Assuntos
Queijo/microbiologia , Escherichia coli O157/crescimento & desenvolvimento , Aditivos Alimentares/análise , Lactobacillus acidophilus/crescimento & desenvolvimento , Óleos Voláteis/análise , Origanum/química , Óleos Vegetais/análise , Rosmarinus/química , Queijo/análise , Escherichia coli O157/efeitos dos fármacos , Aditivos Alimentares/farmacologia , Humanos , Lactobacillus acidophilus/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Paladar
2.
J Agric Food Chem ; 67(50): 13969-13977, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31747272

RESUMO

Various ß-galactosidase enzymes catalyze the trans-glycosylation reaction with lactose. The resulting galactooligosaccharide (GOS) mixtures are widely used in infant nutrition to stimulate growth of beneficial gut bacteria. GOS consists mainly of compounds with a degree of polymerization (DP) varying from 2-8 and with diverse glycosidic linkages. In recent years, we have elucidated in detail the composition of several commercial GOS mixtures in terms of DP and the structural identity of the individual compounds. In this work, 13 (single) probiotic strains of gut bacteria, belonging to 11 different species, were grown to stationary phase with a Vivinal GOS-derived sample purified to remove lactose and monosaccharides (pGOS). Growth among the probiotic strains varied strongly between 30 and 100% of OD600nm relative to positive controls with glucose. By identifying the components of the pGOS mixture that remain after growth, we showed that strains varied in their consumption of specific GOS compounds. All strains commonly used most of the GOS DP2 pool. Lactobacillus salivarius W57 also utilized the DP3 branched compound ß-d-Galp-(1 → 4)-[ß-d-Galp-(1 → 2)]-d-Glc. Bifidobacterial strains tended to use GOS with higher DP and branching than lactobacilli; Bifidobacterium breve DSM 20091, Lactobacillus acidophilus W37, and Bifidobacterium infantis DSM 20088 were exceptional in using 38, 36, and 35 compounds, respectively, out of the 40 different structures identified in pGOS. We correlated these bacterial GOS consumption profiles with their genomic information and were able to relate metabolic activity with the presence of genome-encoded transporters and carbohydrate-active enzymes. These detailed insights may support the design of synbiotic combinations pairing probiotic bacterial strains with GOS compounds that specifically stimulate their growth. Such synbiotic combinations may be of interest in food/feed and/or pharmacy/medicine applications.


Assuntos
Bifidobacterium/metabolismo , Lactobacillus/metabolismo , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Bifidobacterium/crescimento & desenvolvimento , Lactobacillus/crescimento & desenvolvimento , Lactobacillus acidophilus/crescimento & desenvolvimento , Lactobacillus acidophilus/metabolismo , Prebióticos/análise , Probióticos/metabolismo
3.
Acta Sci Pol Technol Aliment ; 18(2): 153-161, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31256543

RESUMO

BACKGROUND: Recently, interest in the development of functional foods enriched with bioactive components has increased. Dairy products supplemented with tea extracts known for their health-promoting properties are good examples of such products. However, most of the scientific studies and applications focus on green tea. The present study was established to estimate the effect of Pu-erh tea supplementation on the viability of starter microorganisms and selected physico-chemical and sensory properties of probiotic ABT-yoghurt. METHODS: ABT-yoghurts (Lactobacillus acidophilus La-5, Bifidobacterium animalis ssp. lactis BB-12, Streptococcus thermophilus) were produced from cow’s milk with 0%, 5%, 10% or 15% (v/v) of Pu-erh tea infusion added before the fermentation stage. The products obtained were subjected to the following analyses one day after production (colour profile) and after 7, 14 and 21 days of cold storage: ferric reducing antioxidant power (FRAP) and anti-radical power (ARP) measured against DPPH radical, titratable acidity, pH, texture parameters (back extrusion test), viability of starter cultures and sensory quality (hedonic scale experiment). RESULTS: Pu-erh tea supplementation significantly enhanced the antioxidant potential of probiotic yoghurts as a 3–6.5-fold increase in FRAP and a 10–24-fold increase in ARP values were observed in comparison to plain ABT-yoghurt. Pu-erh tea slightly enhanced the viability of L. acidophilus and reduced the pH of probiotic yoghurts. Higher concentrations of Pu-erh tea caused decreased firmness and consistency while cohesiveness and index of viscosity remained unaffected upon supplementation. The addition of Pu-erh tea infusion modified the colour and sensory properties of the probiotic yoghurts but the sensory quality of the tea yoghurts was rated lower when compared to the plain one. Among all tea yoghurts, the one with 15% Pu-erh tea additive received the highest scores in sensory assessment. CONCLUSIONS: Pu-erh tea may be successfully applied as a functional additive to probiotic yoghurts, signifi- cantly enhancing the antioxidant properties of fermented milk and ensuring a high rate of starter bacteria viability during storage. However, the level of fortification must be carefully chosen as some doses negatively influence texture parameters and sensory quality.


Assuntos
Antioxidantes/farmacologia , Camellia sinensis , Fermentação , Manipulação de Alimentos/métodos , Probióticos , Chá , Iogurte/análise , Animais , Bifidobacterium animalis/crescimento & desenvolvimento , Bovinos , Suplementos Nutricionais , Feminino , Alimento Funcional , Humanos , Concentração de Íons de Hidrogênio , Lactobacillus acidophilus/crescimento & desenvolvimento , Viabilidade Microbiana , Leite/microbiologia , Extratos Vegetais/farmacologia , Reologia , Streptococcus thermophilus/crescimento & desenvolvimento , Paladar , Viscosidade , Iogurte/microbiologia
4.
Acta Sci Pol Technol Aliment ; 18(2): 185-193, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31256546

RESUMO

BACKGROUND: In yoghurt production, additives and flavours are added after the fermentation process, but in the case of yoghurts with the addition of tea extracts all studies concern set-type yoghurts. For this reason, the aim of this study was to analyse the effect of green, black, red (Pu-erh) and white tea extracts addition on sensory characteristics, pH, viscosity and colour of stirred probiotic yoghurts stored for two weeks. METHODS: Skim milk powder (10% w/w), sucrose (4% w/w) and typical yoghurt cultures with the addition of Lactobacillus acidophilus LA-5 were applied for yoghurt manufacture. Then yoghurts were stirred and 4, 8, 12% black, red, green and white tea extracts were added. The samples were analysed after 1, 3, 7 and 14 days of storage at 5ºC. Instrumental colour (L*a*b*) determination, rheological measurements and sensory evaluation were carried out. RESULTS: The pH analysis of the final yoghurt samples showed that the type and quantity of tea extract addition had little effect. Apparent viscosity was affected by 12% addition of tea extracts but not by storage time. The instrumental analysis of the colour confirmed the visual assessment. Sensory evaluation revealed that yoghurts with the addition of green tea extract were the most accepted. The addition of extracts made of red, black and white tea resulted in lower values of all the sensory characteristics tested. CONCLUSIONS: The stirring method can be applied to the production of probiotic yoghurts with various tea extracts. The acidity of the yoghurts was practically not affected by the addition of the infusion derived from the different types of tea. 4% addition of tea extract did not affect the viscosity of the yoghurts. The best sensory scores among tea yoghurts were obtained by yoghurt with 4% green tea addition.


Assuntos
Camellia sinensis , Fermentação , Manipulação de Alimentos , Probióticos , Chá , Iogurte/análise , Animais , Cor , Alimento Funcional , Humanos , Concentração de Íons de Hidrogênio , Lactobacillus acidophilus/crescimento & desenvolvimento , Leite/microbiologia , Extratos Vegetais , Reologia , Paladar , Viscosidade , Iogurte/microbiologia
5.
Nutrients ; 11(6)2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31181695

RESUMO

Distribution of the microbiota varies according to the location in the gastrointestinal (GI) tract. Thus, dysbiosis during aging may not be limited to faecal microbiota and extend to the other parts of the GI tract, especially the cecum and colon. Lactobacillus acidophilus DDS-1, a probiotic strain, has been shown to modulate faecal microbiota and its associated metabolic phenotype in aging mice. In the present study, we investigated the effect of L. acidophilus DDS-1 supplementation on caecal- and mucosal-associated microbiota, short-chain fatty acids (SCFAs) and immunological profiles in young and aging C57BL/6J mice. Besides differences in the young and aging control groups, we observed microbial shifts in caecal and mucosal samples, leading to an alteration in SCFA levels and immune response. DDS-1 treatment increased the abundances of beneficial bacteria such as Akkermansia spp. and Lactobacillus spp. more effectively in caecal samples than in mucosal samples. DDS-1 also enhanced the levels of butyrate, while downregulating the production of inflammatory cytokines (IL-6, IL-1ß, IL-1α, MCP-1, MIP-1α, MIP-1ß, IL-12 and IFN-γ) in serum and colonic explants. Our findings suggest distinct patterns of intestinal microbiota, improvements in SCFA and immunological profiles with DDS-1 supplementation in aging mice.


Assuntos
Envelhecimento , Ácido Butírico/metabolismo , Disbiose/prevenção & controle , Microbioma Gastrointestinal , Inflamação/prevenção & controle , Lactobacillus acidophilus/crescimento & desenvolvimento , Probióticos/uso terapêutico , Envelhecimento/imunologia , Envelhecimento/metabolismo , Animais , Bactérias/crescimento & desenvolvimento , Ceco/microbiologia , Colo/metabolismo , Colo/microbiologia , Citocinas/sangue , Citocinas/metabolismo , Regulação para Baixo , Disbiose/microbiologia , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Inflamação/microbiologia , Mucosa Intestinal/microbiologia , Camundongos Endogâmicos C57BL , Modelos Animais
6.
Lett Appl Microbiol ; 68(1): 31-37, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30269343

RESUMO

Lactobacillus acidophilus is one of the widespread probiotic bacteria that can overcome acid and bile barrier of stomach and intestine, respectively, and then have beneficial effects on the host improving its intestinal microbial balance. The cell membrane FO F1 -ATPase is an important factor in the response and tolerance to low pH through the action of controlling the H+ concentration between the cell cytoplasm and external medium. In this study, the effects of extremely high-frequency EMI at the frequencies of 51·8 GHz and 53 GHz and cetfazidime ( µmol l-1 ) on survival of L. acidophilus VKM B-1660 in the gastrointestinal model in vitro and on ATPase activity of their membrane vesicles were investigated. Irradiated L. acidophilus survived in media with acid pH; the irradiation stimulated N,N'-dicyclohexylcarbodiimide-sensitive FO F1 -ATPase activity under acidic conditions, but enhanced the inhibitory effects of ceftazidime. Probably irradiated L. acidophilus is overcoming the acid barrier even in the presence of ceftazidime due to the FO F1 -ATPase. The obtained results can allow the use of L. acidophilus in food industry, veterinary and medicine. SIGNIFICANCE AND IMPACT OF THE STUDY: The probiotic property of lactobacilli is defined with survival in different conditions of human digestive tract even in the presence of antibiotics and subjected to electromagnetic irradiation (EMI) at the extremely high frequency. Despite the fact that EMI and antibiotic ceftazidime affected Lactobacillus acidophilus; the viable number of bacterial cells was decreased in in vitro gastrointestinal model, but they could to grow in fresh growth medium. The changes in the FO F1 -ATPase activity were obtained at acidic pH. Thus, these bacteria can overcome acid barrier due to the FO F1 -ATPase: the irradiation stimulates the FO F1 -ATPase activity in the acidic conditions, but enhances the effects of ceftazidime. The results are important for identifying the mechanisms of lactobacilli survival for physical and chemical factors and valuable for use.


Assuntos
Antibacterianos/farmacologia , Ceftazidima/farmacologia , Radiação Eletromagnética , Lactobacillus acidophilus/crescimento & desenvolvimento , ATPases Translocadoras de Prótons/metabolismo , Bile/metabolismo , Membrana Celular/efeitos dos fármacos , Dicicloexilcarbodi-Imida , Trato Gastrointestinal/microbiologia , Humanos , Concentração de Íons de Hidrogênio , Lactobacillus acidophilus/efeitos dos fármacos , Lactobacillus acidophilus/efeitos da radiação , Probióticos
7.
Food Sci Technol Int ; 25(2): 120-129, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30235945

RESUMO

In this study, probiotic bacteria such as Lactobacillus acidophilus and Bifidobacterium bifidum were encapsulated in alginate beads with a mean diameter of 54.25 ± 0.18 µm by internal gelation. Encapsulated and free cells as control samples were then added to the pasteurized grape juice and stored for 60 days. At the end of the storage period, the survivability of the bacteria in the encapsulated samples was significantly ( P<0.05) higher than that in the free cells (8.67 ± 0.12 and 7.57 ± 0.08 log cfu mL-1 for L. acidophilus and 8.27 ± 0.05 and 7.53 ± 0.07 log cfu mL-1 for B. bifidum for encapsulated and free forms, respectively). The results generally showed a decrease in °Brix, pH, and color, whereas acidity and turbidity have increased the in probiotic grape juice after the storage period of 60 days. For all treatments, the numbers of surviving cells were more than the recommended minimum (107 cfu g-1) at the end of the storage period.


Assuntos
Alginatos , Bifidobacterium/crescimento & desenvolvimento , Armazenamento de Alimentos , Sucos de Frutas e Vegetais/microbiologia , Lactobacillus acidophilus/crescimento & desenvolvimento , Probióticos , Vitis , Cápsulas , Frutas , Sucos de Frutas e Vegetais/análise , Humanos , Viabilidade Microbiana , Pasteurização
8.
Int J Biol Macromol ; 121: 870-881, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30342141

RESUMO

Hyaluronic acid (HA) is a natural polymer with various molecular weights that specify multiple biological roles. Traditionally, HA is obtained from animal waste and conventional pathogenic streptococci. However, there are challenges in these processes such as the presence of exotoxins, hyaluronidase, and viral contamination. In order to reduce these problems, this study was conducted to produce HA using recombinant bacterium that is generally recognized as safe (GRAS), and thereafter increase production through experimental design. At first, some lactic acid bacteria were screened and evaluated for HA production. Accordingly, among the selected bacteria, Lactobacillus acidophilus PTCC1643 produced about 0.25 g HA/L in the 48th hour of cultivation, and was thus selected as an alternative host for heterologous HA production. An expression vector containing HA synthase genes was transformed into L. acidophilus by electroporation. Consequently, HA production increased to 0.4 g/L. Eventually, response surface method (RSM) was used, which increased HA production to 1.7 g/L. This is approximately 7-fold higher than that produced at first. The resulting HA was characterized by FTIR spectroscopy and its molecular weight was estimated using agarose gel electrophoresis. In conclusion, L. acidophilus could be a safe, effective, and novel HA producer with industrial potential and commercial prospects.


Assuntos
Meios de Cultura/química , Engenharia Genética , Ácido Hialurônico/biossíntese , Lactobacillus acidophilus/genética , Lactobacillus acidophilus/metabolismo , Eletroporação , Hialuronoglucosaminidase/genética , Hialuronoglucosaminidase/metabolismo , Lactobacillus acidophilus/crescimento & desenvolvimento , Peso Molecular
9.
Anaerobe ; 55: 142-151, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30576791

RESUMO

Clostridium difficile infection is a range of toxin - mediated intestinal diseases that is often acquired in hospitals and small communities in developed countries. The main virulence factors of C. difficile are two exotoxins, toxin A and toxin B, which damage epithelial cells and manifest as colonic inflammation and mild to severe diarrhea. Inhibiting C. difficile adherence, colonization, and reducing its toxin production could substantially minimize its pathogenicity and lead to faster recovery from the disease. This study investigated the efficacy of probiotic secreted bioactive molecules from Lactobacillus acidophilus La-5, in decreasing C. difficile attachment and cytotoxicity in human epithelial cells in vitro. L. acidophilus La-5 cell-free supernatant (La-5 CFS) was used to treat the hypervirulent C. difficile ribotype 027 culture with subsequent monitoring of cytotoxicity and adhesion. In addition, the effect of pretreating cell lines with La-5 CFS in protecting cells from the cytotoxicity of C. difficile culture filtrate or bacterial cell attachment was examined. La-5 CFS substantially reduced the cytotoxicity and cytopathic effect of C. difficile culture filtrate on HT-29 and Caco-2 cells. Furthermore, La-5 CFS significantly reduced attachment of the C. difficile bacterial cells on both cell lines. It was also found that pretreatment of cell lines with La-5 CFS effectively protected cell lines from cytotoxicity and adherence of C. difficile. Our study suggests that La-5 CFS could potentially be used to prevent and cure C. difficile infection and relapses.


Assuntos
Antibacterianos/metabolismo , Antibiose , Toxinas Bacterianas/metabolismo , Infecções por Clostridium/prevenção & controle , Clostridium difficile/crescimento & desenvolvimento , Células Epiteliais/microbiologia , Lactobacillus acidophilus/crescimento & desenvolvimento , Toxinas Bacterianas/toxicidade , Células CACO-2 , Sobrevivência Celular , Clostridium difficile/metabolismo , Meios de Cultura/química , Células Epiteliais/fisiologia , Células HT29 , Humanos , Lactobacillus acidophilus/metabolismo , Modelos Biológicos
10.
Acta Sci Pol Technol Aliment ; 17(3): 247-255, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30269464

RESUMO

BACKGROUND: Magnesium is a micronutrient which plays an important role in a wide range of fundamental cellular reactions. Deficiency of magnesium leads to serious biochemical and symptomatic changes. The present study was carried out to establish the influence of magnesium lactate fortification on the physico- chemical, microbiological and rheological properties of fat-free yogurt manufactured using different starters. METHODS: In this study, yogurts were produced from fat-free milk, standardized with skimmed milk powder to 6% protein content, and then divided into two parts. One part was left without supplementa- tion as a control and in the second part, magnesium L-lactate hydrate was added in the amount of 317.30 mg 100 g–1, which was equal to 35 mg of Mg2+ 100 g–1 of milk. Both mixtures were blended, pasteurized at 85°C for 30 minutes, cooled to 45°C and then divided into three parts, inoculated with: (1) YC-X11 yogurt cul- ture, (2) YF-L811 yogurt culture and (3) VITAL yogurt culture supplemented with probiotics (Lactobacillus acidophilus, Bifidobacterium lactis) respectively. Fermentation was performed at 43°C and the final yogurts were cooled to 5°C. After 24 hours of cold storage, the pH values, titratable acidity, syneresis, color, texture profile, viscosity, sensory analysis and microbiology of the yogurts were analyzed. RESULTS: The results showed that addition of magnesium lactate significantly reduced syneresis and increased the hardness of fat-free yogurts. There was no impact on the viability of starter bacteria in the yogurts after 24 hours of refrigerated storage. CONCLUSIONS: Magnesium lactate showed good potential for the fortification of dairy foods, according to physicochemical data. Further research is needed regarding the influence of storage time and to establish whether the observed effects are largely due to the magnesium cation or lactate anion.


Assuntos
Bactérias/crescimento & desenvolvimento , Manipulação de Alimentos , Alimentos Fortificados , Dureza , Lactatos , Magnésio , Iogurte/análise , Animais , Bifidobacterium/crescimento & desenvolvimento , Dieta com Restrição de Gorduras , Gorduras na Dieta , Fermentação , Humanos , Concentração de Íons de Hidrogênio , Lactobacillus acidophilus/crescimento & desenvolvimento , Hidróxido de Magnésio , Leite/microbiologia , Proteínas do Leite/análise , Minerais , Probióticos , Paladar , Oligoelementos , Viscosidade , Iogurte/microbiologia
11.
FEMS Microbiol Ecol ; 94(9)2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30052968

RESUMO

The early gut microbiome is essential for health, and diet has a profound influence in its composition. Oligosaccharides in breast milk or formula act as prebiotics, influencing gut microbiome structure. Here we simulated the impact of a dietary switch from fructooligosaccharides (FOS) to 2-fucosyllactose (2FL) in a continuous culture containing a consortium of species of the infant gut microbiome. During growth on FOS the consortium was dominated by Lactobacillus acidophilus, characterized by high amounts of lactate. Switching to 2FL led to a decrease in total biomass, and a recovery in Bifidobacterium infantis and Escherichia coli levels. While FOS was rapidly metabolized by the consortium, 2FL was utilized only after a delay. 2FL consumption was followed by a gradual switch from lactate to acetate. The activity of these bacterial species correlated well with gene expression analysis. Mathematical modeling of a multi-species consortium in continuous culture was capable to explain in great part the behavior of the system. The model was finally used to represent the outcome of the system after 48 h after each regime. This work highlights the impact of dietary changes in the gut microbiome, and provides a modeling framework to predict this influence.


Assuntos
Bifidobacterium/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Microbioma Gastrointestinal/efeitos dos fármacos , Lactobacillus acidophilus/crescimento & desenvolvimento , Oligossacarídeos/farmacologia , Prebióticos/análise , Trissacarídeos/farmacologia , Dieta , Feminino , Humanos , Lactente , Leite Humano/química , Modelos Biológicos
12.
PLoS One ; 13(6): e0196941, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29874233

RESUMO

The aim of this study was to compare the effect of Lactobacillus acidophilus on the attachment, invasion, and interaction of Shigella sonnei and Vibrio cholerae with Caco-2 epithelial cells. Also, the anti-apoptotic and anti-inflammatory effect of L. acidophilus was investigated on S. sonnei and V. cholerae interaction with Caco-2 cells as the representatives of invasive and non-invasive intestinal bacteria. It was found that pretreatment with L. acidophilus significantly prevented from adherence and internalization of S. sonnei/V. cholerae and reduced the expression of tumour necrosis factor-α and interleukin-8 in host cells. No significant difference was observed in inhibitory effect of Lactobacilli in V. cholerae and S. sonnei attachment, emphasizing on the role of lactobacilli as a physical barrier in inhibiting direct contact with host cell by competitive exclusion, which may affect attachment and subsequent internalization of both invasive and non-invasive pathogenic bacteria in a same scale. The evaluation of early and late apoptosis in Caco-2 cells exposed to V. cholerae/S. sonnei and pretreated by L. acidophilus indicated no remarkable difference in L. acidophilus anti-apoptotic effect on Caco-2 cells against invasive and non-invasive bacterial infection. Moreover, L. acidophilus by itself showed no apoptotic effect on Caco-2 cells. Statistical analysis revealed that L. acidophilus in S. sonnei infected cells was able to reduce pro-inflammatory immune responses (TNF-α, IL-8 and IL-1ß) and NO and PGE2 secretion more strongly compared with V. cholerae infected cells. These data showed for the first time that the protective effect of Lactobacilli, as a probiotic bacterium, in interaction suppression was more in invasive bacteria including S. sonnei than in non-invasive V. cholerae.


Assuntos
Células Epiteliais/microbiologia , Intestinos/microbiologia , Lactobacillus acidophilus/crescimento & desenvolvimento , Shigella sonnei/crescimento & desenvolvimento , Vibrio cholerae/crescimento & desenvolvimento , Células CACO-2 , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Inflamação/metabolismo , Inflamação/microbiologia , Inflamação/patologia , Interleucina-8/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/patologia , Fator de Necrose Tumoral alfa/metabolismo
13.
Pharm Nanotechnol ; 6(3): 201-208, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29886841

RESUMO

BACKGROUND: Facile, environmental friendly synthesis of metal oxide nanoparticles is of paramount importance when its biological applications are considered. OBJECTIVE: Current study reports phyto-fabrication of Zinc oxide nanoparticles using aqueous extract of Piper betel leaves as stabilizing and capping agent using co-precipitation method. RESULTS: P betel synthesized ZnO nanoparticles (PZnO) was characterized using Powder X-ray diffraction, UV-Visible spectroscopy, scanning electron microscopy and dynamic light scattering. PXRD pattern demonstrated hexagonal wurtzite structure with preferred orientation (100) plane confirmed by JCPDS file 36-1451. UV- Vis spectroscopy showed peak at 370 nm due to band edge of semiconductor, the PZnO. The average particle size determined by DLS measurement was 69 nm and morphologically the particles were short rod shaped and agglomerated as demonstrated by SEM images. Antibacterial activity of PZnO against dental pathogens namely Streptococcus mutans and Lactobacillus acidphillus was performed using well-diffusion method and antioxidant activity against 2, 2 diphenyl 1 picrylhydrazyl (DPPH) free radicals and were compared with ZnO used in clinical dentistry (DZnO). PZnO showed higher antioxidant activity of ~70% at 200 µg/mL with consistent activity at lower aliquots. PZnO showed higher antimicrobial activity than DZnO against both tested microbes and also exhibited inhibitory effects in concentration as low as 3.25 µg/mL. Cytotoxicity study using Balb 3T3 mouse fibroblast cell lines showed <40% cellular growth inhibition by both PZnO and DZnO, indicating their benignity towards selected cell lines. CONCLUSION: Phyto-fabricated facile PZnO nanoparticles having demonstrable antibacterial and antioxidant activity can be considered for use in clinical dentistry after further clinical trials.


Assuntos
Antibacterianos , Antioxidantes , Nanopartículas Metálicas , Piper , Extratos Vegetais , Óxido de Zinco , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Antioxidantes/administração & dosagem , Antioxidantes/química , Células 3T3 BALB , Compostos de Bifenilo/química , Sobrevivência Celular/efeitos dos fármacos , Odontologia , Lactobacillus acidophilus/efeitos dos fármacos , Lactobacillus acidophilus/crescimento & desenvolvimento , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Camundongos , Picratos/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Folhas de Planta/química , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/crescimento & desenvolvimento , Óxido de Zinco/administração & dosagem , Óxido de Zinco/química
14.
Braz. j. microbiol ; 49(2): 303-309, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889222

RESUMO

Abstract Soymilk was produced from vegetable soybean and fermented by probiotics (Lactobacillus acidophilus La-5, Bifidobacterium animalis Bb-12) in co-culture with Streptococcus thermophilus. The composition of the fermented beverage and oligosaccharides content were determined. The effect of fructooligosaccharides and inulin on the fermentation time and viability of probiotic microorganisms throughout 28 days of storage at 5 °C were evaluated. The soymilk from vegetable soybeans was fermented in just 3.2 h, when pH reached 4.8. Fermentation reduced the contents of stachyose and raffinose in soymilk. Prebiotics had no effect on acidification rate and on viability of B. animalis and S. thermophilus in the fermented beverage. The viable counts of B. animalis Bb-12 remained above 108 CFU mL-1 in the fermented soymilk during 28 days of storage at 5 °C while L. acidophilus La-5 was decreased by 1 log CFU mL-1. The fermented soymilk from vegetable soybeans showed to be a good food matrix to deliver probiotic bacteria, as well as a soy product with a lower content of non-digestible oligosaccharides.


Assuntos
Bebidas/análise , Leite de Soja/metabolismo , Streptococcus thermophilus/metabolismo , Simbióticos , Bifidobacterium animalis/metabolismo , Lactobacillus acidophilus/metabolismo , Oligossacarídeos/análise , Temperatura , Contagem de Colônia Microbiana , Leite de Soja/isolamento & purificação , Streptococcus thermophilus/crescimento & desenvolvimento , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Fermentação , Bifidobacterium animalis/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Inulina/análise , Lactobacillus acidophilus/crescimento & desenvolvimento
15.
Food Funct ; 9(5): 2979-2988, 2018 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-29767655

RESUMO

Stachyose is a functional oligosaccharide, acting as a potential prebiotic for colonic fermentation. To understand the mechanism of how stachyose promotes the growth of probiotic bacterium, we analyzed the differences of the proteome of Lactobacillus acidophilus grown on stachyose or glucose. By a combination of two-dimensional electrophoresis and mass spectrometry analysis, we observed 16 proteins differentially abundant under these two conditions and identified 9 protein spots. Six of these proteins were highly abundant when stachyose was used as the sole carbon source. They included the phosphotransferase system, the energy coupling factor (ECF) transporter and the mannose-6-phosphate isomerase, involved in the uptake and catabolism of stachyose in Lactobacillus acidophilus CICC22162. Supportively, these observations were validated by quantitative RT-PCR analysis and enzymatic activity determination. Positive correlation was found between the content of the proteins and their mRNA levels. Additionally, we explored the recognition mechanism for stachyose binding to the newly identified ECF transporter by MD simulations and free energy analysis. Taken together, these results provide new insights into the mechanism of stachyose in promoting the growth of probiotic bacterium.


Assuntos
Lactobacillus acidophilus/crescimento & desenvolvimento , Lactobacillus acidophilus/metabolismo , Oligossacarídeos/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Eletroforese em Gel Bidimensional , Lactobacillus acidophilus/genética , Probióticos/química , Probióticos/metabolismo , Proteoma/química , Proteoma/genética , Proteoma/metabolismo , Proteômica
16.
J Microbiol Methods ; 148: 145-150, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29656125

RESUMO

The purpose of the study is to develop the new methodology of strategic ultrasound treatment on lactic acid bacteria (LAB) to induce stress response for the enhancement of ß-glucosidase activity that can be used for the biotransformation of glucosides into aglycones isoflavones in soymilk. Among the five LAB tested, Lactobacillus acidophilus BCRC 10695 showed the best ability to release ß-glucosidase for further ultrasonic stimulation to induce proper stress response. With ultrasound (20 kHz, amplitude at 20%) to irradiate on L. acidophilus BCRC 10695 at stationary phase of growth for 2 min and 24 h of re-incubation, the ß-glucosidase activity was enhanced to 3.91 U/ml, which was 1.82 times of that without ultrasound treatment. Using the ultrasound-treated L. acidophilus BCRC 10695 to ferment soymilk, the fraction of aglycones in total isoflavones in soymilk was effectively increased from 21.8% initially to 97.9% in 24 h. The strategic ultrasound treatment on L. acidophilus BCRC 10695 demonstrated promotion of ß-glucosidase activity, and this methodology had the potential to be applied in the production of functional soymilk by adding probiotics LAB to increase the bioactive isoflavones and nutritional values for human health.


Assuntos
Isoflavonas/metabolismo , Lactobacillus acidophilus/metabolismo , Lactobacillus acidophilus/efeitos da radiação , Sonicação/métodos , beta-Glucosidase/metabolismo , Biotransformação , Fermentação , Lactobacillus acidophilus/enzimologia , Lactobacillus acidophilus/crescimento & desenvolvimento , Leite de Soja/metabolismo
17.
J Hosp Infect ; 99(4): 443-452, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29702133

RESUMO

Clostridium difficile infection (CDI) has become the leading healthcare-associated infection and cause of outbreaks around the world. Although various innovative treatments have been developed, preventive strategies using multi-faceted infection control programmes have not been successful in reducing CDI rates. The major risk factor for CDI is the disruption of the normally protective gastrointestinal microbiota, typically by antibiotic use. Supplementation with specific probiotics has been effective in preventing various negative outcomes, including antibiotic-associated diarrhoea and CDI. However, a consensus of which probiotic strains might prevent CDI has not been reached and meta-analyses report high degrees of heterogeneity when studies of different probiotic products are pooled together. We searched the literature for probiotics with sufficient evidence to assess clinical efficacy for the prevention of CDI and focused on one specific probiotic formulation comprised of three lactobacilli strains (Lactobacillus acidophilus CL1285, Lactobacillus casei LBC80R, Lactobacillus rhamnosus CLR2, Bio-K+) for its ability to prevent CDI in healthcare settings. A literature search on this probiotic formulation was conducted using electronic databases (PubMed, Google Scholar), abstracts from infectious disease and infection control meetings, and communications from the probiotic company. Supporting evidence was found for its mechanisms of action against CDI and that it has an excellent safety and tolerability profile. Evidence from randomized controlled trials and facility-level interventions that administer Bio-K+ show reduced incidence rates of CDI. This probiotic formulation may have a role in primary prevention of healthcare-associated CDI when administered to patients who receive antibiotics.


Assuntos
Infecções por Clostridium/prevenção & controle , Lactobacillus acidophilus/crescimento & desenvolvimento , Lactobacillus casei/crescimento & desenvolvimento , Lactobacillus rhamnosus/crescimento & desenvolvimento , Prevenção Primária/métodos , Probióticos/administração & dosagem , Humanos , Incidência , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
18.
Proteomics ; 18(5-6): e1700308, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29412508

RESUMO

Many health effects of Lactobacillus acidophilus are desirable among these the adhesion ability is vital to enhance the possibility of colonization and stabilization associated with the gut mucosal barrier. In this study, the growth characteristics and the adhesion activity of L. acidophilus in the intestine-like pH environment (pH 7.5) are identified. The number of bacteria adhering to the HT-29 cells is found with a gradual increase trend (pH 5.5-7.5). This also leads to the morphological changes of L. acidophilus after exposure to different pH environments. Furthermore, with the help of the isobaric tags for relative and absolute quantification (iTRAQ) proteomic analysis, 207 proteins are detected differentially expressed at pH of 7.5. The use of GO analysis and KEGG analysis indicates three essential pathways related to the cell envelope peptide-glycan biosynthesis, carbohydrate metabolism, and amino acid metabolism are obviously changed. Adhesion related surface protein fmtB and PrtP are upregulated in pH 7.5 group. While the moonlight proteins like pyruvate kinase, which binds specifically to the mucin layer and inhibits the adhesive activity of L. acidophilus, is found downregulated. These results could be useful to understand the adhesion mechanism of L. acidophilus adapting for the gut mucosal barrier in the intestinal environment.


Assuntos
Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Intestinos/fisiologia , Lactobacillus acidophilus/crescimento & desenvolvimento , Lactobacillus acidophilus/metabolismo , Proteínas de Membrana/metabolismo , Proteoma/análise , Proteínas de Bactérias/genética , Células HT29 , Humanos , Concentração de Íons de Hidrogênio , Intestinos/microbiologia , Proteínas de Membrana/genética
19.
Appl Microbiol Biotechnol ; 102(6): 2635-2644, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29427145

RESUMO

Date syrup is rich in fermentable sugars and may be used as a substrate for different microbial fermentations, including lactic acid fermentation processes. The beneficial effects of ultrasounds (US) on bioprocesses have been reported for several microorganisms, due to the enhancement of cell growth, as well as improvements in yields and productivities. Therefore, US treatments (30 kHz, 100 W, 10-30 min) were applied to two lactobacilli (Lactobacillus helveticus PTCC 1332 and Lactobacillus acidophilus PTCC 1643), during fermentation using date syrup as substrate. The effects on lactic acid fermentation were evaluated by analyzing cell growth (dry cell weight and viable cell count), substrate consumption (quantification of glucose and fructose), and product formation (quantification of lactic acid) over time. The effects of US were also evaluated on cell membrane permeability. Both lactobacilli were able to grow well on date syrup without the need for addition of further ingredients. The US effects were highly dependent on treatment duration: treatments of 10- and 20-min stimulated lactobacilli growth, while the treatment extension to 30 min negatively affected cell growth. Similarly, the 10- and 20-min treatments increased sugar consumption and lactic acid production, contrarily to the 30-min treatment. All US treatments increased cell membrane permeability, with a more pronounced effect at more extended treatments. The results of this work showed that application of appropriate US treatments could be a useful tool for stimulation of lactic acid production from date syrup, as well as for other fermentative processes that use date syrup as substrate.


Assuntos
Ácido Láctico/metabolismo , Lactobacillus acidophilus/metabolismo , Lactobacillus acidophilus/efeitos da radiação , Lactobacillus helveticus/metabolismo , Lactobacillus helveticus/efeitos da radiação , Extratos Vegetais , Ultrassonografia , Membrana Celular/efeitos da radiação , Fermentação , Lactobacillus acidophilus/crescimento & desenvolvimento , Lactobacillus helveticus/crescimento & desenvolvimento , Permeabilidade/efeitos da radiação , Phoeniceae , Fatores de Tempo
20.
Braz J Microbiol ; 49(2): 303-309, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29122477

RESUMO

Soymilk was produced from vegetable soybean and fermented by probiotics (Lactobacillus acidophilus La-5, Bifidobacterium animalis Bb-12) in co-culture with Streptococcus thermophilus. The composition of the fermented beverage and oligosaccharides content were determined. The effect of fructooligosaccharides and inulin on the fermentation time and viability of probiotic microorganisms throughout 28 days of storage at 5°C were evaluated. The soymilk from vegetable soybeans was fermented in just 3.2h, when pH reached 4.8. Fermentation reduced the contents of stachyose and raffinose in soymilk. Prebiotics had no effect on acidification rate and on viability of B. animalis and S. thermophilus in the fermented beverage. The viable counts of B. animalis Bb-12 remained above 108CFUmL-1 in the fermented soymilk during 28 days of storage at 5°C while L. acidophilus La-5 was decreased by 1logCFUmL-1. The fermented soymilk from vegetable soybeans showed to be a good food matrix to deliver probiotic bacteria, as well as a soy product with a lower content of non-digestible oligosaccharides.


Assuntos
Bebidas/análise , Bifidobacterium animalis/metabolismo , Lactobacillus acidophilus/metabolismo , Leite de Soja/metabolismo , Streptococcus thermophilus/metabolismo , Simbióticos , Bifidobacterium animalis/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Fermentação , Concentração de Íons de Hidrogênio , Inulina/análise , Lactobacillus acidophilus/crescimento & desenvolvimento , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Oligossacarídeos/análise , Leite de Soja/isolamento & purificação , Streptococcus thermophilus/crescimento & desenvolvimento , Temperatura
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