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1.
Braz J Microbiol ; 55(2): 1279-1286, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38652443

RESUMO

Probiotic-containing foods are among the most appreciated functional foods; however, probiotic-based dairy products cannot be consumed by people who are lactose intolerant, allergic to milk, or vegetarian or vegan individuals. Thus, new non-dairy matrices have been tested for probiotics delivery. This study evaluated the growth and viability of Limosilactobacillus fermentum ATCC 23271 and Lacticaseibacillus rhamnosus ATCC 9595 in Pitanga juice (Eugenia uniflora L.). The effects of the fermentation on the antioxidant and anti-infective properties of the juice were also analyzed. The E. uniflora juice allowed lactobacilli growth without supplementation, reaching rates around 8.4 Log CFU/mL and producing organic acids (pH values < 4) after 72 h of fermentation. The strain remained viable after 35 days of refrigerated storage. Fermentation by these bacteria increases the antioxidant capacity of the juice. The central composite rotational design was employed to evaluate the effects of bacterial inoculum and pulp concentration on growth and organic acids production by L. fermentum ATCC 23271. The strain was viable and produced organic acids in all tested combinations. L. fermentum-fermented juice and its cell-free supernatant significantly increased the survival of Tenebrio molitor larvae infected by enteroaggregative Escherichia coli 042. The results obtained in this study provide more insights into the potential of Pitanga juice to develop a functional non-dairy probiotic beverage with antioxidant and anti-infective properties.


Assuntos
Antioxidantes , Eugenia , Fermentação , Limosilactobacillus fermentum , Probióticos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Limosilactobacillus fermentum/metabolismo , Limosilactobacillus fermentum/crescimento & desenvolvimento , Limosilactobacillus fermentum/fisiologia , Limosilactobacillus fermentum/efeitos dos fármacos , Probióticos/farmacologia , Eugenia/química , Anti-Infecciosos/farmacologia , Sucos de Frutas e Vegetais/microbiologia , Sucos de Frutas e Vegetais/análise , Lacticaseibacillus rhamnosus/metabolismo , Lacticaseibacillus rhamnosus/crescimento & desenvolvimento , Lacticaseibacillus rhamnosus/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos
2.
Probiotics Antimicrob Proteins ; 14(5): 960-979, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35467236

RESUMO

The unbalance in the production and removal of oxygen-reactive species in the human organism leads to oxidative stress, a physiological condition commonly linked to the occurrence of cancer, neurodegenerative, inflammatory, and metabolic disorders. The implications of oxidative stress in the gut have been associated with gut microbiota impairments and gut dysbiosis. Some lactobacilli strains have shown an efficient antioxidant system capable of protecting against oxidative stress and related-chronic diseases. Recently, in vitro and experimental studies and some clinical trials have demonstrated the efficacy of the administration of various Limosilactobacillus fermentum strains to modulate beneficially the host antioxidant system resulting in the amelioration of a variety of systemic diseases phenotypes. This review presents and discusses the currently available studies on identifying L. fermentum strains with anti-oxidant properties, their sources, range of the administered doses, and duration of the intervention in experiments with animals and clinical trials. This review strives to serve as a relevant and well-cataloged reference of L. fermentum strains with capabilities of inducing anti-oxidant effects and health-promoting benefits to the host, envisaging their broad applicability to disease control.


Assuntos
Microbioma Gastrointestinal , Limosilactobacillus fermentum , Probióticos , Animais , Antioxidantes/metabolismo , Disbiose , Humanos , Limosilactobacillus fermentum/metabolismo , Probióticos/farmacologia
3.
Lett Appl Microbiol ; 74(6): 981-991, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35247276

RESUMO

The antibacterial activity of citrus essential oils (EOs) in the context of combating Limosilactobacillus fermentum, one of the most important bacterial contaminants in the bioethanol production industry, has never been explored previously. Industrial processes usually utilize sulfuric acid for cell treatment to decrease bacterial contamination. However, due to the hazardous nature of sulfuric acid, an alternative to it is highly desirable. Therefore, in the present study, the efficacy of Fremont IAC 543 mandarin EO against a strain of L. fermentum (ATCC® 9338™) was evaluated under proliferative/nonproliferative conditions, in both pure culture and co-culture with an industrial strain of Saccharomyces cerevisiae. The mandarin EO exhibited higher effectiveness against L. fermentum compared to that against S. cerevisiae under nonproliferative conditions (added to water rather than to culture medium). At the concentration of 0·05%, the EO was as effective as the acid solution with pH 2·0 in reducing the count of L. fermentum almost 5 log CFU ml-1 cycles, while the concentration of 0·1% led to the complete loss of bacterial culturability. When L. fermentum was co-cultured with S. cerevisiae, the efficacy of the EO against the bacterial strain was reduced. However, despite this reduced efficacy in co-culture, mandarin EO may be considered effective in combating L. fermentum and could be applied in processes where this bacterium proves to be unfavourable and does not interact with S. cerevisiae.


Assuntos
Limosilactobacillus fermentum , Óleos Voláteis , Antibacterianos/metabolismo , Etanol/metabolismo , Fermentação , Microbiologia Industrial , Limosilactobacillus fermentum/metabolismo , Óleos Voláteis/farmacologia , Saccharomyces cerevisiae/metabolismo
4.
Sci Rep ; 11(1): 21691, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34737363

RESUMO

We characterized two LysM domains of Limosilactobacillus fermentum, belonging to proteins Acglu (GenBank: KPH22907.1) and Pgb (GenBank: KPH22047.1) and bacterium like particles (BLP) derived from the immunomodulatory strain Lacticaseibacillus rhamnosus IBL027 (BLPs027) as an antigen display platform. The fluorescence protein Venus fused to the novel LysM domains could bind to the peptidoglycan shell of lactobacilli and resisted harsh conditions such as high NaCl and urea concentrations. Acglu with five LysM domains was a better anchor than Pgb baring only one domain. Six-week-old BALB/c mice were nasally immunized with the complex Venus-Acglu-BLPs027 at days 0, 14 and 28. The levels of specific serum IgG, IgG1 and IgG2a and the levels of total immunoglobulins (IgT) and IgA in broncho-alveolar lavage (BAL) were evaluated ten days after the last boosting. Venus-Acglu-BLPs027, nasally administered, significantly increased specific BAL IgT and IgA, and serum IgG levels. In addition, spleen cells of mice immunized with Venus-Acglu-BLPs027 secreted TNF-α, IFN-γ and IL-4 when stimulated ex vivo in a dose-dependent manner. We constructed a Gateway compatible destination vector to easily fuse the selected LysM domain to proteins of interest for antigen display to develop mucosal subunit vaccines.


Assuntos
Imunidade nas Mucosas/imunologia , Limosilactobacillus fermentum/imunologia , Limosilactobacillus fermentum/metabolismo , Adjuvantes Imunológicos , Administração Intranasal , Animais , Feminino , Imunização/métodos , Imunoglobulina A/imunologia , Lactobacillus/imunologia , Lactobacillus/metabolismo , Lacticaseibacillus rhamnosus/imunologia , Lacticaseibacillus rhamnosus/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Domínios Proteicos/imunologia , Vacinação
5.
Food Res Int ; 131: 109034, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32247478

RESUMO

Cocoa fermentation is a spontaneous process shaped by a variable microbial ecosystem which is assembled due to cross-feeding relationship among yeasts and bacteria, resulting in a synchronized microbial succession started by yeasts, followed by lactic acid bacteria (LAB) and finalized by acetic acid bacteria (AAB). Several studies have indicated the effect of microbial interactions in food ecosystems highlighting the importance of quorum sensing (QS) in bacterial adaptation in harsh environments modulating several phenotypes such as biofilm formation, tolerance to acid stress, bacteriocin production, competence, morphological modifications, motility, among others. However, antagonic interactions also occur, and can be marked by Quorum Quenching (QQ) activity, negatively impacting QS regulated phenotypes. Our current knowledge regarding microbial cocoa composition and functioning is based on culture-based analysis and culture-independent PCR-based methods. Therefore, we set out to investigate the application of metagenomics analysis on a classical spontaneous cocoa fermentation in order to describe: (I) the microbial taxonomic composition; (II) the functional potential of the cocoa microbiome; (III) the microbiome putative QS potential; and (IV) the microbiome QQ potential. Both aims III and IV are related to the expression of effectors that may confer advantageous traits along fermentation which can explain their dominance in specific time zones during the entire process. We have observed a bacterial succession shaped by yeasts and filamentous fungi and then Enterobacteriaceales, LAB and AAB, as well as a diverse genetic metabolic potential related to proteins and carbohydrates metabolism associated to the yeast Saccharomyces cerevisiae and members of the Enterobacteriaceales order and LAB and AAB groups. In addition, in silico evidences of interspecific QS arsenal were found in members of the genera Enterobacter, Lactobacillus, Bacillus and Pantoea, while inferences of intraspecific QS potential were found in the members of the genera Bacillus, Enterobacter, Komagataeibacter, Lactobacillus and Pantoea. In addition, a QQ potential was detected in Lactobacillus and in AAB members. These findings indicate that QS and QQ may modulate bacterial dominance in different time points during fermentation, along with cross-feeding, being responsible for their maintenance in a large time range.


Assuntos
Cacau/microbiologia , Fermentação , Percepção de Quorum/fisiologia , Ácido Acético/metabolismo , Bactérias/classificação , Bactérias/metabolismo , Cacau/metabolismo , Simulação por Computador , Alimentos Fermentados/microbiologia , Manipulação de Alimentos , Microbiologia de Alimentos , Limosilactobacillus fermentum/classificação , Limosilactobacillus fermentum/metabolismo , Metagenômica , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/metabolismo , Análise de Sequência de DNA
6.
Probiotics Antimicrob Proteins ; 12(4): 1459-1470, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31970648

RESUMO

The aim of this study was to assess the protective effect of the intracellular content obtained from potential probiotic bacteria against acrylamide-induced oxidative damage in human erythrocytes. First, the antioxidant properties of 12 potential probiotic strains was evaluated. Two commercial probiotic bacteria were included as reference strains, namely, Lactobacillus casei Shirota and Lactobacillus paracasei 431. Data showed that the intracellular content from four strains, i.e., Lactobacillus fermentum J10, Lactobacillus pentosus J24 and J26, and Lactobacillus pentosus J27, showed higher (P < 0.05) antioxidant capacity in most methods used. Thereafter, the intracellular content of such pre-selected strains was able to prevent the disturbance of the antioxidant system of human erythrocytes exposed to acrylamide, thereby reducing cell disruption and eryptosis development (P < 0.05). Additionally, the degree of oxidative stress in erythrocytes exposed to acrylamide was significantly (P < 0.05) reduced to levels similar to the basal conditions when the intracellular content of Lact. fermentum J10, Lact. pentosus J27, and Lact. paracasei 431 were employed. Hence, our findings suggest that the intracellular contents of specific Lactobacillus strains represent a potential source of metabolites with antioxidant properties that may help reduce the oxidative stress induced by acrylamide in human erythrocytes.


Assuntos
Acrilamida/farmacologia , Antioxidantes/farmacologia , Misturas Complexas/farmacologia , Lacticaseibacillus casei/química , Lacticaseibacillus paracasei/química , Lactobacillus pentosus/química , Limosilactobacillus fermentum/química , Acrilamida/antagonistas & inibidores , Antioxidantes/química , Catalase/metabolismo , Células Cultivadas , Cromanos/farmacologia , Misturas Complexas/química , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Lacticaseibacillus casei/metabolismo , Limosilactobacillus fermentum/metabolismo , Lacticaseibacillus paracasei/metabolismo , Lactobacillus pentosus/metabolismo , Malondialdeído/antagonistas & inibidores , Malondialdeído/metabolismo , Oxirredução , Estresse Oxidativo , Probióticos/química , Superóxido Dismutase/metabolismo
7.
Food Microbiol ; 86: 103339, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31703886

RESUMO

The study of microbial communities associated with spontaneous fermentation of agave juice for tequila production is required to develop starter cultures that improve both yield and quality of the final product. Quantification by HPLC of primary metabolites produced during the fermentations was determined. A polyphasic approach using plate count, isolation and identification of microorganisms, denaturing gradient gel electrophoresis and next generation sequencing was carried out to describe the diversity and dynamics of yeasts and bacteria during small-scale spontaneous fermentations of agave juice from two-year samplings. High heterogeneity in microbial populations and fermentation parameters were observed, with bacteria showing higher diversity than yeast. The core microorganisms identified were Saccharomyces cerevisiae and Lactobacillus fermentum. Practices in tequila production changed during the two-year period, which affected microbial community structure and the time to end fermentation. Bacterial growth and concomitant lactic acid production were associated with low ethanol production, thus bacteria could be defined as contaminants in tequila fermentation and efforts to control them should be implemented.


Assuntos
Bebidas Alcoólicas/microbiologia , Bactérias/metabolismo , Leveduras/isolamento & purificação , Agave/química , Agave/microbiologia , Bebidas Alcoólicas/análise , Bactérias/química , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , Etanol/metabolismo , Fermentação , Cinética , Limosilactobacillus fermentum/química , Limosilactobacillus fermentum/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Leveduras/química , Leveduras/genética , Leveduras/metabolismo
8.
Int J Food Microbiol ; 304: 106-118, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31176963

RESUMO

Nicaraguan cocoa bean fermentations of several single local cocoa varieties originating from the same region (North Highlands of Nicaragua, San Jose de Bocay/El Cuá) were compared to fermentations of blended cocoa varietals from other producing regions of the country (Waslala and Nueva Guinea) making use of High Throughput Sequencing techniques, metabolite target analysis and sensory evaluation of cocoa liquor samples. A succession of the important cocoa-related yeasts Hanseniaspora uvarum/opuntiae, Saccharomyces cerevisiae and/or Pichia kudriavzevii was seen for single varietals and Nueva Guinea fermentations, while Kazachstania humilis dominated the mid and end phase of the Waslala cocoa fermentations. Tatumella species (mainly Tatumella terrea and Tatumella punctata) predominated the bacterial community at the onset of all fermentations followed by unusually late (generally 2 days into the fermentations) appearance of Lactobacillus fermentum relative to fermentations in other parts of the World. Acetobacter spp. were the main acetic acid bacteria during all fermentations, but also Gluconobacter spp. were involved in some single-variety fermentations. All fermentations proved complete as determined by metabolite analysis with bean sucrose being fully depleted and pulp sugars exhausted after 48-72 h of fermentation. From an organoleptic point of view, all Nicaraguan cocoas of this study reflected fine fruity (citrus or berry-like) flavours with distinct herbal or caramel notes. Floral notes were associated with the cases where P. kudriavzevii was involved in the later stages of fermentation. Intense citrus/fruity character was related to high pulp and bean citrate concentrations. Off-notes were found in some over-fermented batches where Bacillus spp. was detected. No relation between cut-test results and organoleptic appreciation was seen.


Assuntos
Bactérias/metabolismo , Cacau/microbiologia , Chocolate/microbiologia , Fermentação/fisiologia , Fungos/metabolismo , Ácido Acético/metabolismo , Acetobacter/metabolismo , Bactérias/isolamento & purificação , Reatores Biológicos/microbiologia , Enterobacteriaceae/metabolismo , Fungos/isolamento & purificação , Gluconobacter/metabolismo , Hanseniaspora/metabolismo , Limosilactobacillus fermentum/metabolismo , Pichia/metabolismo , Saccharomyces cerevisiae/metabolismo
9.
Food Res Int ; 121: 812-816, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31108812

RESUMO

Helicobacter pylori, a gastric carcinogenic pathogen, colonizes the stomach of 50% of the human population and is considered as a WHO priority 2 due to its antibiotics resistance. Therefore, research should aim to avoid H. pylori infection. Probiotics are an emerging alternative to handle this pathogen, making it necessary to have means to evaluate their effectiveness. This work evaluated the effect of a carrageenan encapsulated probiotic, Lactobacillus fermentum UCO-979C strain, against the pathogenic H. pylori SS1 strain under simulated gastric conditions (fasting or standard diet, pH 3.0 under microaerophilic condition and agitation). Samples were obtained from simulators up to 2.5 h after adding the probiotic, either planktonic or carrageenan encapsulated, and H. pylori were counted using enriched Columbia agar. Gastric simulations under fasting or standard diet showed collaboration between L. fermentum and carrageenan against the pathogen, it is undetectable at 1.5 or 2.5 h, respectively, allowing to conclude that the administration of the probiotic under fasting (harsher acid environment) provides a better anti-H. pylori effect that administering it associated with the diet. Thus, it can be suggested to consume low pH resistant probiotics under fasting.


Assuntos
Carragenina/química , Células Imobilizadas/microbiologia , Helicobacter pylori/metabolismo , Limosilactobacillus fermentum/metabolismo , Probióticos , Estômago/microbiologia , Jejum , Microbioma Gastrointestinal , Concentração de Íons de Hidrogênio , Viabilidade Microbiana
10.
Sci Rep ; 9(1): 5625, 2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30948743

RESUMO

The purpose of this work was to model the survival of the microorganism and the kinetics of drying during the encapsulation of Lactobacillus fermentum K73 by Refractance Window drying. A whey culture medium with and without addition of maltodextrin were used as encapsulation matrices. The microorganism with the encapsulation matrices was dried at three water temperatures (333, 343 and 353 K) until reaching balanced moisture. Microorganism survival and thin layer drying kinetics were studied by using mathematical models. Results showed that modified Gompertz model and Midilli model described the survival of the microorganism and the drying kinetics, respectively. The most favorable process conditions found with the mathematical modelling were a drying time of 2460 s, at a temperature of 353 K. At these conditions, a product with 9.1 Log CFU/g and a final humidity of 10% [wet basis] using the culture medium as encapsulation matrix was obtained. The result shows that Refractance Window can be applied to encapsulate the microorganism probiotic with a proper survival of the microorganism.


Assuntos
Encapsulamento de Células/métodos , Limosilactobacillus fermentum/metabolismo , Limosilactobacillus fermentum/fisiologia , Dessecação/métodos , Liofilização/métodos , Umidade , Viabilidade Microbiana , Modelos Teóricos , Probióticos , Temperatura , Proteínas do Soro do Leite
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