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1.
J Dairy Sci ; 105(8): 6513-6526, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35840409

RESUMO

Natural whey cultures (NWC) are undefined multiple-strain bacterial starter communities that can be affected by even small changes along the entire dairy chain. We applied a multidisciplinary approach to investigate how the addition of 2 mycotoxin-detoxifying agents [sodium smectite and lignocellulose-based material (B1); leonardite and betaine (B2)] to cow diets modified the microbiota of the NWC in manufacture of a Grana-like cheese. Microbiological and flow cytometry analyses showed that the content and viability of lactic acid bacteria (LAB) and the total whey microbiota were not affected by the detoxifying agents, and Streptococcus thermophilus, Lactobacillus helveticus, and Limosilactobacillus fermentum were the dominant taxa. Random amplified polymorphic DNA-PCR fingerprinting and metagenomic analysis highlighted differences in the bacterial community of the NWC and in the relative abundance of Bacteroidetes that increased when B1 and B2 were included in the diet. Two of 6 St. thermophilus biotypes were detected only in control samples; conversely, none of the Lb. helveticus biotypes found in control samples were isolated from B1 and B2. In vitro tests showed that the 2 binders did not significantly affect the development of St. thermophilus, but they stimulated the growth of Lb. helveticus strains recovered only from B1 and B2 NWC. The addition of binders in cow feed can affect the LAB biotypes present in NWC.


Assuntos
Queijo , Lactobacillus helveticus , Micotoxinas , Ração Animal/análise , Animais , Biodiversidade , Bovinos , Queijo/análise , DNA Bacteriano/análise , Microbiologia de Alimentos , Micotoxinas/análise , Soro do Leite/química , Proteínas do Soro do Leite/análise
2.
Nutrients ; 14(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35405944

RESUMO

Probiotics are suggested to impact physiological and psychological stress responses by acting on the gut-brain axis. We investigated if a probiotic product containing Bifidobacterium longum R0175, Lactobacillus helveticus R0052 and Lactiplantibacillus plantarum R1012 affected stress processing in a double-blinded, randomised, placebo-controlled, crossover proof-of-concept study (NCT03615651). Twenty-two healthy subjects (24.2 ± 3.4 years, 6 men/16 women) underwent a probiotic and placebo intervention for 4 weeks each, separated by a 4-week washout period. Subjects were examined by functional magnetic resonance imaging while performing the Montreal Imaging Stress Task (MIST) as well as an autonomic nervous system function assessment during the Stroop task. Reduced activation in regions of the lateral orbital and ventral cingulate gyri was observed after probiotic intervention compared to placebo. Significantly increased functional connectivity was found between the upper limbic region and medioventral area. Interestingly, probiotic intervention seemed to predominantly affect the initial stress response. Salivary cortisol secretion during the task was not altered. Probiotic intervention did not affect cognitive performance and autonomic nervous system function during Stroop. The probiotic intervention was able to subtly alter brain activity and functional connectivity in regions known to regulate emotion and stress responses. These findings support the potential of probiotics as a non-pharmaceutical treatment modality for stress-related disorders.


Assuntos
Bifidobacterium longum , Lactobacillus helveticus , Probióticos , Encéfalo/diagnóstico por imagem , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Masculino
3.
Comput Math Methods Med ; 2022: 4968016, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35265172

RESUMO

Objective: To study the preventive effect of Lactobacillus helveticus (L. helveticus) on periodontitis induced by Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) in rats. Methods: Eighteen 8-week-old female rats were randomly divided into three groups: Sham group, Trehalose group, and L. helveticus SBT2171 (LH2171) group. We measured the distance of the cementoenamel junction-alveolar bone crest (CEJ-ABC) to evaluate alveolar bone resorption. Hematoxylin-eosin staining was used to observe the histopathological changes of rat hemimaxillary tissues. We detected the expression of ß-defensins, tumor necrosis factor-α (TNF-α), interleukin- (IL-) 1ß, and IL-6 and the number of A. actinomycetemcomitans in rat gingival tissues by quantitative reverse transcriptase polymerase chain reaction. The levels of IL-1ß, IL-6, and TNF-α in rat gingival tissues were also measured by enzyme-linked immunosorbent assay. Results: Compared with the Trehalose group, the distance of CEJ-ABC was prominently reduced and alveolar bone resorption was notably improved in the LH2171 group. And the infiltration of inflammatory cells in the hemimaxillary tissue decreased obviously, periodontal fibers were arranged neatly, connective tissue small blood vessels proliferated, and the number of A. actinomycetemcomitans reduced significantly in the LH2171 group. In addition, the mRNA expression and release of inflammatory factors in the gingival tissues in the LH2171 group were notably lower than those in the Trehalose group. On the 21st and 36th day, the expression of ß-defensins in the gingival tissue of the LH2171 group increased significantly. Conclusion: L. helveticus improves alveolar bone resorption and increases the expression of ß-defensins thereby inhibiting the number of A. actinomycetemcomitans and thus prevents periodontitis.


Assuntos
Aggregatibacter actinomycetemcomitans/patogenicidade , Lactobacillus helveticus/fisiologia , Periodontite/prevenção & controle , beta-Defensinas/fisiologia , Perda do Osso Alveolar/etiologia , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/prevenção & controle , Animais , Biologia Computacional , Modelos Animais de Doenças , Feminino , Gengiva/microbiologia , Mediadores da Inflamação/metabolismo , Periodontite/microbiologia , Periodontite/fisiopatologia , Probióticos/farmacologia , Ratos , Ratos Sprague-Dawley , Trealose/farmacologia
4.
Int J Biol Macromol ; 208: 314-323, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35278514

RESUMO

In order to study the mechanism of high viscosity of Sayram ketteki yoghurt, the growth, acidification properties, in situ exopolysaccharides (EPS) production of Lactobacillus helveticus MB2-1 in milk medium were investigated. The microstructure of the yoghurt was analyzed. The characteristics of in situ EPS produced by this strain in yoghurt were studied by high-performance liquid chromatography (HPLC), Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible (UV-vis) analysis. The amount of in situ EPS produced could be up to 689.47 mg/L. The micrographs of Sayram ketteki yoghurt demonstrated that the in situ EPS secreted by ropy L. helveticus MB2-1 were closely connected with proteins, effectively filling the three-dimensional network structure of casein clusters, thereby resulting in high viscosity of yoghurt. Besides, the molecular weight of in situ EPS was 9.34 × 104 Da, and the in situ EPS was determined to be a new heteropolysaccharide, containing fucose, which made it unique. Moreover, the set yoghurts added with in situ EPS were demonstrated fine effects on the texture improvement. These results illustrated that L. helveticus MB2-1 could be set as a good starter and the in situ EPS could be considered as a probiotic stabilizer substitute for fermented dairy products.


Assuntos
Produtos Fermentados do Leite , Lactobacillus helveticus , Fermentação , Lactobacillus helveticus/química , Polissacarídeos Bacterianos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Iogurte
5.
J Sci Food Agric ; 102(3): 1095-1104, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34312867

RESUMO

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitory peptides are potential alternatives to the synthetic ACE inhibitory drugs, but the in vivo antihypertensive effects of most of them have not been confirmed. The tripeptide Leu-Pro-Pro (LPP) is one of the few peptides that have been proved clinically effective in reducing the blood pressure of hypertensive patients and casein is currently its major source. LPP is contained in multiple fractions of zein, and corn gluten meal (CGM) is hence a potential new source of LPP. For this purpose, CGM was fermented with a Lactobacillus helveticus strain and the medium composition was optimized; the decoloration of the resultant hydrolysate was investigated as well. RESULTS: LPP could be successfully released from CGM by fermentation with the strain Lactobacillus helveticus CICC 22536. The highest LPP content and protein recovery of 561 mg kg-1 and 14.92% occurred in the medium containing 20 g L-1 glucose, 15 g L-1 beef extract, 60 g L-1 CGM, 10 g L-1 CaCO3 , 0.5 g L-1 NaCl, and inoculation amount 6%. The supplementation of Flavourzyme® further improved the two parameters to 662 mg kg-1 and 36.94%, respectively. The permeate of the hydrolysate after ultrafiltration through a 5 kDa membrane could be effectively decolored by the macroporous resin XAD-16 without notable protein loss, and its LPP content was further boosted to 743 mg kg-1 . CONCLUSION: CGM is a potential new source of LPP and its ultrafiltered and decolored hydrolysate could be used to develop new antihypertensive functional foods. © 2021 Society of Chemical Industry.


Assuntos
Glutens/metabolismo , Lactobacillus helveticus/metabolismo , Oligopeptídeos/metabolismo , Zea mays/química , Zea mays/microbiologia , Inibidores da Enzima Conversora de Angiotensina/análise , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Anti-Hipertensivos/análise , Anti-Hipertensivos/isolamento & purificação , Anti-Hipertensivos/metabolismo , Fermentação , Glutens/análise , Oligopeptídeos/análise , Oligopeptídeos/isolamento & purificação
6.
J Nutr Biochem ; 99: 108858, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34587540

RESUMO

Inflammatory bowel disease (IBD) is a group of chronic inflammatory gastrointestinal diseases that causes worldwide suffering. L. helveticus is a probiotic that can enhance intestinal barrier function via alleviation of excessive inflammatory response. Citrulline, a functional amino acid, has been reported to stimulate muscle synthesis and to function with a prebiotic-like action with certain Lactobacillus strains. The aim of this study was to investigate the potential synergistic effect of combining L. helveticus and citrulline on protection against damage induced by dextran sulfate sodium (DSS) in a mouse model. 6-week-old male C57BL/6J mice were fed with DSS water and randomly divided for administering with different milk treatments: 1) plain milk (control or DSS control), 2) 1% (w/v) citrulline enriched milk (Cit_milk), 3) milk fermented with L. helveticus (LHFM) and 4) DSS+milk fermented with L. helveticus with 1% (w/v) citrulline (Cit_LHFM). The treatment effects on the survival and macroscopic and microscopic signs were examined. All treatments presented different degrees of protective effects on attenuating the damages induced by DSS. All treatments reduced the body weight loss, disease activity index (DAI), histological scores, pro-inflammatory cytokine expression (IL-6, TNF-α and IFN-γ) and production (IL-4) (all P <0.05) and the tight junction (TJ) protein (zonula occluden-1 (ZO-1) expression. LHFM and Cit_LHFM improved survival rate (both at P<0.05). Particularly, Cit_LHFM showed greater effects on protecting the damages induced by DSS, especially in ameliorating colonic permeability, TJ protein (ZO-1, occludin and claudin-1) expression and distribution as well as in reducing IL-4 and IL-17 expression (all P <0.05). Our findings suggested that the combination of and citrulline had significant synergistic effect on protecting against injury from DSS-induced colitis. Therefore, citrulline enriched L. helveticus fermented milk is suggested to be a potential therapy for treating IBD.


Assuntos
Citrulina/metabolismo , Colite/dietoterapia , Produtos Fermentados do Leite/microbiologia , Lactobacillus helveticus/metabolismo , Animais , Citrulina/análise , Colite/induzido quimicamente , Colite/genética , Colite/metabolismo , Produtos Fermentados do Leite/análise , Sulfato de Dextrana/efeitos adversos , Humanos , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-4/genética , Interleucina-4/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Leite/metabolismo , Leite/microbiologia , Proteínas de Junções Íntimas/genética , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismo
7.
PLoS One ; 16(12): e0250234, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34914726

RESUMO

AIM: To investigate the effect of influenza vaccination with or without probiotic supplementation on the immune response and incidence of influenza-like illness (ILI) in the elderly. METHODS: A randomized double-blind, placebo-controlled trial with a modified factorial design was conducted in 554 healthy elderly subjects aged 67 ± 5.6 (ranging from 60-90) years old in the Primary Health Care Center (Puskesmas area) of the Pulo Gadung District East Jakarta. Subjects received either a trivalent influenza vaccine or placebo at the start of the study, and a probiotic supplement (Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011) or a placebo for 6 months. Subjects were randomly assigned into four intervention groups: influenza vaccine and probiotics (n = 141), influenza vaccine and placebo (n = 136), placebo and probiotics (n = 140), and both placebo (n = 137). The primary outcome was ILI incidence within 6 months. The secondary outcomes were seroprotection and seroconversion rates at 1, 4, and 6 months after administering the interventions. RESULTS: This study showed that the trivalent influenza vaccine increased seroprotection (RR 3.6 [95%CI 2.92-4.47]; p<0.010) and seroconversion (RR 29.8 [95%CI 11.1-79.5]; p<0.010) rates 1 month after vaccination in elderly people while the probiotic supplement did not alter influenza antibody titers (p = 1.000 and p = 0.210). The relative ILI incidence risk was similar between vaccinated and non-vaccinated groups, as well as in the probiotic group compared to the non-probiotic group. CONCLUSION: The tested trivalent influenza vaccine significantly induced seroprotection and seroconversion in the vaccinated subjects, while probiotics administration did not influence these parameters. Vaccinated individuals displayed a similarly low ILI incidence as those in the Control Group. However, the observed trend towards a reduction of ILI incidence with probiotics supplementation warrants further assessments in a larger, at-risk population. CLINICAL TRIAL REGISTRY NUMBER: NCT03695432.


Assuntos
Vacinas contra Influenza/administração & dosagem , Influenza Humana , Lactobacillus helveticus , Lactobacillus rhamnosus , Probióticos/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Humanos , Incidência , Indonésia/epidemiologia , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade
8.
J Dairy Sci ; 104(11): 11499-11508, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34454765

RESUMO

Cow milk protein is one of the leading food allergens. This study aimed to develop an effective method for reducing milk sensitization by evaluating antigenicity of fermented skim milk protein using Lactobacillus helveticus KLDS 1.8701, Lactobacillus plantarum KLDS 1.0386, and a combination of both strains. The proteolytic systems of strains in terms of genotype and phenotype are characterized by complete genome sequence, and evaluation the antigenicity of skim milk proteins was determined by ELISA and liquid chromatography with tandem mass spectrometry. Our results showed that the genomes encoded a variety of peptidase genes. For fermented skim milk, the degree of hydrolysis of the combined strains was higher than that of individual strain. Electrophoresis showed that the band color density of α-casein (α-CN) by fermentation of the combined strains was reduced when compared with control group. The fermentation process of the combined strains inhibited α-CN, ß-lactoglobulin, and α-lactalbumin antigenicity by 69.13, 36.10, and 20.92, respectively. Major allergic epitopes of α-CN and ß-lactoglobulin were cleaved by abundant proteases of combined strains. In all, this study showed that the fermentation process involving both L. helveticus and L. plantarum strains could reduce cow milk protein allergenicity through the combination of cell-envelope proteinase and peptidase on α-CN.


Assuntos
Lactobacillus helveticus , Lactobacillus plantarum , Alérgenos , Animais , Bovinos , Feminino , Fermentação , Proteínas do Leite
9.
Int J Biol Macromol ; 187: 664-674, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34339781

RESUMO

Symbiotic bacteria, including members of the Bacteroides genus, are known to digest dietary fibers in the gastrointestinal tract. The metabolism of complex carbohydrates is restricted to a specified subset of species and is likely orchestrated by polysaccharide utilization loci (PULs) in these microorganisms. ß-Mannans are plant cell wall polysaccharides that are commonly found in human nutrients. Here, we report the structural basis of a PUL cluster, BdPUL12, which controls ß-mannan-like glycan catabolism in Bacteroides dorei. Detailed biochemical characterization and targeted gene disruption studies demonstrated that a key glycoside hydrolase, BdP12GH26, performs the initial attack on galactomannan or glucomannan likely via an endo-acting mode, generating mannooligosaccharides and mannose. Importantly, coculture assays showed that the B. dorei promoted the proliferation of Lactobacillus helveticus and Bifidobacterium adolescentis, likely by sharing mannooligosaccharides and mannose with these gut probiotics. Our findings provide new insights into carbohydrate metabolism in gut-inhabiting bacteria and lay a foundation for novel probiotic development.


Assuntos
Proteínas de Bactérias/metabolismo , Bacteroides/enzimologia , Galactose/análogos & derivados , Mananas/metabolismo , Manose/metabolismo , Manosidases/metabolismo , Oligossacarídeos/metabolismo , Probióticos , Proteínas de Bactérias/genética , Bacteroides/genética , Bacteroides/crescimento & desenvolvimento , Bifidobacterium adolescentis/crescimento & desenvolvimento , Bifidobacterium adolescentis/metabolismo , Galactose/metabolismo , Microbioma Gastrointestinal , Hidrólise , Lactobacillus helveticus/crescimento & desenvolvimento , Lactobacillus helveticus/metabolismo , Manosidases/genética , Simbiose
10.
J Dairy Sci ; 104(10): 10540-10549, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34275634

RESUMO

Gas production by obligatory heterofermentative lactic acid bacteria such as Paucilactobacillus wasatchensis is a sporadic problem in Cheddar cheese and results in undesired slits and cracks in the cheese. Growth of Pa. wasatchensis is not rapid, which makes investigations of gas production difficult to consistently execute. A primary objective of this study was to develop a model gas production test that could be used to investigate the effect of galactose and ribose utilization on gas production by Pa. wasatchensis and determine whether galactose-fermenting adjunct cultures could prevent gas formation. Paucilactobacillus wasatchensis WDC04 was inoculated at 101 to 106 cfu/mL into carbohydrate-restricted MRS broth containing different ribose and galactose levels and incubated for up to 21 d at 23°C. Gas production in the broth was detected using a Durham tube inverted on a 6-cm-long capillary tube; cells were enumerated at 4, 8, and 12 d; and residual galactose was also measured. Gas production was sporadic except for when 105 cfu/mL of Pa. wasatchensis WDC04 was inoculated into broth containing 0.3% ribose and 0.7% galactose. In those tubes, gas production was consistently observed after 8-d incubation, by which time galactose levels had decreased to 0.15%. Co-inoculation of Pa. wasatchensis WDC04 with as few as 103 cfu/mL of a lactose-negative galactose-positive adjunct culture (Pediococcus acidilactici 23F, Lacticaseibacillus paracasei UW4, or Lactobacillus helveticus 7995) resulted in galactose depletion by d 4 and no observable gas production by d 12. With less galactose available to the slower-growing Pa. wasatchensis WDC04, its growth was limited to 108 cfu/mL when any of the adjunct cultures was co-inoculated, compared with 109 cfu/mL when grown on its own. We concluded that galactose-fermenting adjunct cultures have potential for preventing unwanted gas production in cheese by competition for resources and especially by removing the 6-carbon galactose before it can be utilized for energy by an obligatory heterofermentative lactobacilli such as Pa. wasatchensis and produce carbon dioxide.


Assuntos
Queijo , Lactobacillus helveticus , Animais , Queijo/análise , Microbiologia de Alimentos , Galactose , Lactose
11.
Am J Clin Nutr ; 113(4): 905-914, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-34269370

RESUMO

BACKGROUND: We previously conducted the Probiotic Regimen for Outpatient Gastroenteritis Utility of Treatment (PROGUT) study, which identified no improvements in children with acute gastroenteritis (AGE) administered a probiotic. However, the aforementioned study did not evaluate immunomodulatory benefits. OBJECTIVES: The object of this study was to determine if stool secretory immunoglobulin A (sIgA) concentrations in children with AGE increase more among participants administered a Lactobacillus rhamnosus/helveticus probiotic compared with those administered placebo. METHODS: This a priori planned multicenter, randomized, double-blinded, placebo-controlled ancillary study enrolled children presenting for emergency care who received a 5-d probiotic or placebo course. Participants submitted stool specimens on days 0, 5, and 28. The primary endpoint was the change in stool sIgA concentrations on day 5 compared with baseline. RESULTS: A total of 133 (n = 66 probiotic, 67 placebo) of 886 PROGUT participants (15.0%) provided all 3 specimens. Median stool sIgA concentrations did not differ between the probiotic and placebo groups at any of the study time points: day 0 median (IQR): 1999 (768, 4071) compared with 2198 (702, 5278) (P = 0.27, Cohen's d = 0.17); day 5: 2505 (1111, 5310) compared with 3207 (982, 7080) (P = 0.19, Cohen's d = 0.16); and day 28: 1377 (697, 2248) compared with 1779 (660, 3977) (P = 0.27, Cohen's d = 0.19), respectively. When comparing measured sIgA concentrations between days 0 and 5, we found no treatment allocation effects [ß: -0.24 (-0.65, 0.18); P = 0.26] or interaction between treatment and specimen collection day [ß: -0.003 (-0.09, 0.09); P = 0.95]. Although stool sIgA decreased between day 5 and day 28 within both groups (P < 0.001), there were no differences between the probiotic and placebo groups in the median changes in sIgA concentrations when comparing day 0 to day 5 median (IQR) [500 (-1135, 2362) compared with 362 (-1122, 4256); P = 0.77, Cohen's d = 0.075] and day 5 to day 28 [-1035 (-3130, 499) compared with -1260 (-4437, 843); P = 0.70, Cohen's d = 0.067], respectively. CONCLUSIONS: We found no effect of an L. rhamnosus/helveticus probiotic, relative to placebo, on stool IgA concentrations. This trial was registered at clinicaltrials.gov as NCT01853124.


Assuntos
Fezes/microbiologia , Gastroenterite/terapia , Imunoglobulina A Secretora , Imunomodulação , Lactobacillus helveticus/imunologia , Lactobacillus rhamnosus/imunologia , Probióticos/uso terapêutico , Doença Aguda/terapia , Serviços Médicos de Emergência , Feminino , Gastroenterite/microbiologia , Humanos , Lactente , Masculino
12.
Am J Gastroenterol ; 116(7): 1523-1532, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34183579

RESUMO

INTRODUCTION: It is unclear whether the alleged efficacy of probiotics in childhood acute gastroenteritis depends on the duration and severity of symptoms before treatment. METHODS: Preplanned secondary analysis of 2 randomized placebo-controlled trials in children 3-48 months of age was conducted in 16 emergency departments in North America evaluating the efficacy of 2 probiotic products (Lactobacillus rhamnosus GG and a combination probiotic: L. rhamnosus and L. helveticus). Participants were categorized in severity groups according to the duration (<24, 24-<72, and ≥72 hours) and the frequency of diarrhea episodes in the 24 hours (≤3, 4-5, and ≥6) before presentation. We used regression models to assess the interaction between pretreatment diarrhea severity groups and treatment arm (probiotic or placebo) in the presence of moderate-to-severe gastroenteritis (Modified Vesikari Scale score ≥9). Secondary outcomes included diarrhea frequency and duration, unscheduled healthcare provider visits, and hospitalization. RESULTS: A total of 1,770 children were included, and 882 (50%) received a probiotic. The development of moderate-to-severe gastroenteritis symptoms after the initiation of treatment did not differ between groups (probiotic-18.4% [162/882] vs placebo-18.3% [162/888]; risk ratio 1.00; 95% confidence interval 0.87, 1.16; P = 0.95). There was no evidence of interaction between baseline severity and treatment (P = 0.61) for the primary or any of the secondary outcomes: diarrhea duration (P = 0.88), maximum diarrheal episodes in a 24-hour period (P = 0.87), unscheduled healthcare visits (P = 0.21), and hospitalization (P = 0.87). DISCUSSION: In children 3-48 months with acute gastroenteritis, the lack of effect of probiotics is not explained by the duration of symptoms or frequency of diarrheal episodes before presentation.


Assuntos
Diarreia/terapia , Gastroenterite/terapia , Probióticos/uso terapêutico , Pré-Escolar , Feminino , Humanos , Lactente , Lactobacillus helveticus , Lactobacillus rhamnosus , Masculino , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
13.
Microb Genom ; 7(4)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33900907

RESUMO

Lactobacillus helveticus is a well characterized lactobacillus for dairy fermentations that is also found in malt whisky fermentations. The two environments contain considerable differences related to microbial growth, including the presence of different growth inhibitors and nutrients. The present study characterized L. helveticus strains originating from dairy fermentations (called milk strains hereafter) and malt whisky fermentations (called whisky strains hereafter) by in vitro phenotypic tests and comparative genomics. The whisky strains can tolerate ethanol more than the milk strains, whereas the milk strains can tolerate lysozyme and lactoferrin more than the whisky strains. Several plant-origin carbohydrates, including cellobiose, maltose, sucrose, fructooligosaccharide and salicin, were generally metabolized only by the whisky strains, whereas milk-derived carbohydrates, i.e. lactose and galactose, were metabolized only by the milk strains. Milk fermentation properties also distinguished the two groups. The general genomic characteristics, including genomic size, number of coding sequences and average nucleotide identity values, differentiated the two groups. The observed differences in carbohydrate metabolic properties between the two groups correlated with the presence of intact specific enzymes in glycoside hydrolase (GH) families GH1, GH4, GH13, GH32 and GH65. Several GHs in the milk strains were inactive due to the presence of stop codon(s) in genes encoding the GHs, and the inactivation patterns of the genes encoding specific enzymes assigned to GH1 in the milk strains suggested a possible diversification manner of L. helveticus strains. The present study has demonstrated how L. helveticus strains have adapted to their habitats.


Assuntos
Lactobacillus helveticus/isolamento & purificação , Lactobacillus helveticus/fisiologia , Leite/microbiologia , Vinho/microbiologia , Adaptação Fisiológica , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bovinos , Etanol/metabolismo , Fermentação , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Lactobacillus helveticus/classificação , Lactobacillus helveticus/genética
14.
J Pept Sci ; 27(7): e3329, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33860571

RESUMO

Tyrosinase is a copper-containing enzyme involved in the biosynthesis of melanin pigment, which is the most important photo protective agent against skin photo carcinogenesis. Excess production of melanin causes hyperpigmentation leading to undesired browning in human skin, fruits, and vegetable as well as plant-derived foods. Moreover, the role of tyrosinase in the onset and progression of various diseases such as cancers, Alzheimer's, and Parkinson diseases has been well documented in the literature. In this respect, tyrosinase inhibitors have been in the center of attention particularly as the efficient skin whitening agents. Among a wide range of compounds possessing anti-tyrosinase activity, peptides both natural and synthetic derivatives have attracted attention due to high potency and safety.


Assuntos
Produtos Biológicos/farmacologia , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Peptídeos/farmacologia , Produtos Biológicos/síntese química , Produtos Biológicos/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Lactobacillus helveticus/química , Monofenol Mono-Oxigenase/metabolismo , Peptídeos/síntese química , Peptídeos/química
15.
Chembiochem ; 22(10): 1765-1768, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33523590

RESUMO

The use of nicotinamide cytosine dinucleotide (NCD), a biocompatible nicotinamide adenosine dinucleotide (NAD) analogue, is of great scientific and biotechnological interest. Several redox enzymes have been devised to favor NCD, and have been successfully applied in creating NCD-dependent redox systems. However, molecular interactions between cofactor and protein have still to be disclosed in order to guide further engineering efforts. Here we report the structural analysis of an NCD-favoring malic enzyme (ME) variant derived from Escherichia coli. The X-ray crystal structure data revealed that the residues located at position 346 and 401 in ME acted as the "gatekeepers" of the adenine moiety binding cavity. When Arg346 was substituted with either acidic or aromatic residues, the corresponding mutants showed substantially reduced NCD preference. Inspired by these observations, we generated Lactobacillus helveticus derived d-lactate dehydrogenase variants at Ile177, the counterpart to Arg346 in ME, and found a similar trend in terms of cofactor preference changes. As many NAD-dependent oxidoreductases share key structural features, our results provide guidance for protein engineering to obtain more NCD-favoring variants.


Assuntos
Proteínas de Bactérias/metabolismo , Malato Desidrogenase/metabolismo , NAD/química , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sítios de Ligação , Cristalografia por Raios X , Escherichia coli/enzimologia , L-Lactato Desidrogenase/química , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Lactobacillus helveticus/enzimologia , Malato Desidrogenase/química , Simulação de Dinâmica Molecular , Mutagênese Sítio-Dirigida , NAD/metabolismo , Oxirredução
16.
Sci Rep ; 11(1): 3763, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33580118

RESUMO

Social stress exacerbates anxious and depressive behaviors in humans. Similarly, anxiety- and depressive-like behaviors are triggered by social stress in a variety of non-human animals. Here, we tested whether oral administration of the putative anxiolytic probiotic strains Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 reduces the striking increase in anxiety-like behavior and changes in gut microbiota observed following social defeat stress in Syrian hamsters. We administered the probiotic at two different doses for 21 days, and 16S rRNA gene amplicon sequencing revealed a shift in microbial structure following probiotic administration at both doses, independently of stress. Probiotic administration at either dose increased anti-inflammatory cytokines IL-4, IL-5, and IL-10 compared to placebo. Surprisingly, probiotic administration at the low dose, equivalent to the one used in humans, significantly increased social avoidance and decreased social interaction. This behavioral change was associated with a reduction in microbial richness in this group. Together, these results demonstrate that probiotic administration alters gut microbial composition and may promote an anti-inflammatory profile but that these changes may not promote reductions in behavioral responses to social stress.


Assuntos
Comportamento Animal/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Probióticos/farmacologia , Animais , Ansiolíticos/farmacologia , Ansiedade/tratamento farmacológico , Ansiedade/microbiologia , Bifidobacterium longum , Microbioma Gastrointestinal/fisiologia , Lactobacillus helveticus , Mesocricetus/microbiologia , Mesocricetus/fisiologia , Comportamento Social , Derrota Social , Estresse Psicológico/metabolismo , Estresse Psicológico/microbiologia
17.
PLoS One ; 16(1): e0245903, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33493208

RESUMO

Lactobacillus helveticus carries many properties such as the ability to survive gastrointestinal transit, modulate the host immune response, accumulate biopeptides in milk, and adhere to the epithelial cells that could contribute to improving host health. In this study, the applicability as functional cultures of four L. helveticus strains isolated from Italian hard cheeses was investigated. A preliminary strain characterization showed that the ability to produce folate was generally low while antioxidant, proteolytic, peptidase, and ß-galactosidase activities resulted high, although very variable, between strains. When stimulated moDCs were incubated in the presence of live cells, a dose-dependent release of both the pro-inflammatory cytokine IL-12p70 and the anti-inflammatory cytokine IL-10, was shown for all the four strains. In the presence of cell-free culture supernatants (postbiotics), a dose-dependent, decrease of IL-12p70 and an increase of IL-10 was generally observed. The immunomodulatory effect took place also in Caciotta-like cheese made with strains SIM12 and SIS16 as bifunctional (i.e., immunomodulant and acidifying) starter cultures, thus confirming tests in culture media. Given that the growth of bacteria in the cheese was not necessary (they were killed by pasteurization), the results indicated that some constituents of non-viable bacteria had immunomodulatory properties. This study adds additional evidence for the positive role of L. helveticus on human health and suggests cheese as a suitable food for delivering candidate strains and modulating their anti-inflammatory properties.


Assuntos
Queijo/microbiologia , Lactobacillus helveticus/isolamento & purificação , Microbiologia de Alimentos , Humanos , Itália , Lactobacillus helveticus/genética , Lactobacillus helveticus/metabolismo , Leucócitos Mononucleares/metabolismo
18.
Food Microbiol ; 94: 103651, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33279076

RESUMO

Lactobacillus (L.) helveticus is widely used in food industry due to its high proteolytic activity. However, such activity varies greatly between isolates, and the determining factors regulating the strength of proteolytic activity in L. helveticus are unclear. This study sequenced the genomes of 60 fermented food-originated L. helveticus and systemically examined the proteolytic activity-determining factors. Our analyses found that the strength of proteolytic activity in L. helveticus was independent of the isolation source, geographic location, phylogenetic closeness between isolates, and distribution of cell envelope proteinases (CEPs). Genome-wide association study (GWAS) identified two genes, the acetate kinase (ackA) and a hypothetical protein, and 15 single nucleotide polymorphisms (SNPs) that were associated with the strength of the proteolytic activity. Further investigating the functions of these gene components revealed that ackA and two cysteine peptidases coding genes (pepC and srtA) rather than the highly heterogeneous and intraspecific CEPs were linked to the level of proteolytic activity. Moreover, the sequence type (ST) defined by SNP analysis revealed a total of ten STs, and significantly weaker proteolytic activity was observed among isolates of ST2. This study provides practical information for future selection of L. helveticus of strong proteolytic activity.


Assuntos
Acetato Quinase/metabolismo , Proteínas de Bactérias/metabolismo , Laticínios/microbiologia , Grão Comestível/microbiologia , Lactobacillus helveticus/enzimologia , Peptídeo Hidrolases/metabolismo , Acetato Quinase/química , Acetato Quinase/genética , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Bovinos , Genoma Bacteriano , Estudo de Associação Genômica Ampla , Lactobacillus helveticus/genética , Lactobacillus helveticus/isolamento & purificação , Lactobacillus helveticus/metabolismo , Peptídeo Hidrolases/química , Peptídeo Hidrolases/genética , Filogenia , Proteólise
19.
Food Chem ; 340: 128152, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33032150

RESUMO

Soy protein isolates were fermented by three commercial Lactobacillus helveticus strains for a maximum of seven days to investigate the resulting proteolysis. The proteolytic activity of the most active strain (LH88) was further analyzed (LC-MS/MS and GC-MS) and it was shown that the ß-conglycinin α subunit 1, ß-conglycinin α' subunit, glycinin G1, and 2S albumin were specifically degraded. Peptigram analysis and visualization of the crystal structure showed that the hydrolysis sites of ß-conglycinin α subunit, α' subunit, and the glycinin G1 were located on the surface of the molecule or at the mobile disordered region, hence being highly accessible for the proteinase of LH88. The proteins were partially further degraded to free amino acids, and subsequently catabolized to volatile compounds. However, most of the proteins remained native, even after seven days of fermentation, thus additional modification of protein structure or adjustment of fermentation conditions are required for effective generation of flavor compounds.


Assuntos
Lactobacillus helveticus/metabolismo , Proteínas de Soja/metabolismo , Aminoácidos/análise , Técnicas de Cultura Celular por Lotes , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Lactobacillus helveticus/crescimento & desenvolvimento , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/metabolismo , Peptídeos/análise , Peptídeos/metabolismo , Proteólise , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/isolamento & purificação , Proteínas de Armazenamento de Sementes/metabolismo , Proteínas de Soja/química , Proteínas de Soja/isolamento & purificação , Espectrometria de Massas em Tandem , Compostos Orgânicos Voláteis/análise
20.
Food Chem ; 341(Pt 1): 128180, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33032249

RESUMO

Lactobacillus helveticus FAM22155 was the most efficient among five lactic acid bacteria at removing aflatoxin B1 (AFB1) during solid-state fermentation on wheat bran substrate. The mechanism of removal was explored by comparing different fermentation modes. Liquid fermentation had little effect on the breakdown of AFB1. However, a protein extract from the fermented bran was equally effective at degrading aflatoxin B1 as living cell digestion. After treatment with heat and protease K, the degrading capacity of the protein extract was significantly reduced. Taken together, the observed biotransformation of AFB1 was mainly associated with proteins produced during bran fermentation. Four products of U-[13C17]-AFB1 were found by mass spectrometry, including Ⅱ-1 (C11H10O4), Ⅱ-2 (C11H10O4), III (C15H12O5), and IV (C14H10O4). These products all lack the lactone ring indicating lower toxicity than aflatoxin B1.


Assuntos
Aflatoxina B1/metabolismo , Fibras na Dieta/microbiologia , Lactobacillus helveticus/metabolismo , Aflatoxina B1/análise , Biotransformação , Fibras na Dieta/metabolismo , Fermentação , Microbiologia de Alimentos , Lactobacillales/metabolismo
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