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1.
Food Microbiol ; 106: 104059, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35690435

RESUMO

Thirty-seven lactic acid bacteria (LAB) strains were isolated from traditional dry sausages collected from Northeast China, including Latilactobacillus sakei (29 strains), Lactiplantibacillus plantarum (4 strains), Latilactobacillus curvatus (2 strains), Weissella hellenica (1 strain), and Lactococcus lactis (1 strain). Some LAB strains had tolerance to high concentrations of sodium chloride (6%), sodium nitrite (150 mg/L NaNO2), and acid (pH 4.0). They showed good growth and acidification properties and antimicrobial activity. Among them, five LAB strains that exhibited the best technological properties were selected and inoculated in the sausage model to explore their roles in flavor development. The contents of total free amino acids (FAAs) decreased ranging from 109.11 mg/g to 58.06 mg/g. A total of 46 volatile compounds were identified and the contents of volatile compounds increased in the sausage model during fermentation. Partial least squares regression analysis showed that Lb. sakei HRB10, Lb. plantarum MDJ2, W. hellenica HRB6, and Lc. lactis HRB0 promoted the generation of FAAs and volatile compounds in the sausage model. These findings demonstrated that the autochthonous LAB species are promising for the production of sausage with better flavor and fermentation performance.


Assuntos
Lactobacillales , Lactobacillus sakei , Produtos da Carne , Fermentação , Microbiologia de Alimentos , Produtos da Carne/microbiologia
2.
Int J Food Microbiol ; 366: 109575, 2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35176610

RESUMO

Latilactobacillus sakei comprises a biodiversity of strains, which display different assertiveness upon their application as starter cultures in raw sausage fermentation. While the assertiveness of winning partner strains has been referred to competitive exclusion based on genomic settings enabling occupation of multiple niches of the sausage habitat, single strain assertiveness of L. sakei remained unexplained. In this study we assessed the impact of the expression of a glycosyltransferase enabling the production of a glucan from sucrose to the assertiveness of L. sakei TMW 1.411, which expresses a plasmid-encoded glycosyltransferase (gtf). In a sausage fermentation model wild type L. sakei TMW 1.411 and its plasmid-cured mutant were employed in competition with each other and with other Latilactobacillus sakei strains. To differentiate any effects resulting from general sugar utilization from those of glucan formation, the experiments were carried out with glucose, fructose, and sucrose, respectively. It was shown that the type of sugar affects the individual strains behaviour, and that the wild type was more competitive than the mutant in the presence of any of these sugars. In direct competition between wild type and mutant, a clear competitive advantage could also be demonstrated for the strain possessing the plasmid with the glycosyltransferase. Since this competitive advantage was observed with all sugars, not just sucrose, and Gtf expression has been shown as independent of the employed sugar, it is suggested that possession of the gtf gene-carrying plasmid confers a competitive advantage. It appears that the Gtf contributes to competitive exclusion and the establishment of colonization resistance, to a larger extent by an adhesive functionality of the Gtf on the cellular surface than by the production of glucan. Hence, gtf genes can be used as a possible additional marker for the selection of assertive L. sakei starter strains in sausage fermentation.


Assuntos
Glicosiltransferases , Lactobacillus sakei/metabolismo , Produtos da Carne , Açúcares , Fermentação , Glicosiltransferases/genética , Produtos da Carne/microbiologia , Açúcares/metabolismo
3.
Microbiol Res ; 256: 126954, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34973546

RESUMO

Lactic acid bacteria that inhabit in the lung play important roles in maintaining the microbiome balance by interacting with the host immune system. Numerous metabolites (e.g., short chain fatty acids, bacteriocins, and hydrogen peroxide) produced by Lactobacillus sakei possess a special inhibitory spectrum against invading pathogens. In this research, the whole genome of L. sakei JD10 strain isolated from the porcine lung was sequenced and investigated. The whole size of the L. sakei JD10 chromosome was 1,989,921 bp, which encoded a total of 1951 predicted genes. Genome analyses revealed that many genes encoded carbohydrate-active enzymes (CAZymes) were predicted, which were responsible for the carbohydrate degradation and short chain fatty acids production. The metabolic profiles of short chain fatty acids in the L. sakei JD10 culture medium were measured by GC/TOFMS, and their regulatory effects on bacterial phagocytosis of RAW264.7 cells were also determined. The bacteriocin-producing genes of the L. sakei JD10 genome were also predicted, and a bacteriocin gene encoding carnocin was characterized and its molecular structure was analyzed. Two CRISPR-Cas system related genes were identified from the L. sakei JD10 genome, revealed that precise and efficient genome editing technologies could be applied for genetic engineering-manipulation. In all, investigation on the genomic features and metabolic features of L. sakei JD10 showed the potential probiotic traits to fight against pathogenic infection and regulate the host immune function.


Assuntos
Bacteriocinas , Lactobacillus sakei , Probióticos , Animais , Bacteriocinas/genética , Genômica , Lactobacillus sakei/genética , Lactobacillus sakei/metabolismo , Suínos
4.
Int J Food Microbiol ; 363: 109491, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-34862040

RESUMO

Biopreservation is a strategy that has been extensively covered by the scientific literature from a variety of perspectives. However, the development of quantitative modelling approaches has received little attention, despite the usefulness of these tools for the food industry to assess the performance and to set the optimal application conditions. The objective of this study was to evaluate and model the interaction between the antilisteria strain Latilactobacillus sakei CTC494 (sakacin K producer) and Listeria monocytogenes in vacuum-packaged sliced cooked ham. Cooked ham was sliced under aseptic conditions and inoculated with L. monocytogenes CTC1034 and/or L. sakei CTC494 in monoculture and coculture at 10:10, 10:103 and 10:105 cfu/g ratios of pathogen:bioprotective cultures. Samples were vacuum packaged and stored at isothermal temperature (2, 5, 10 and 15 °C). The growth of the two bacteria was monitored by plate counting. The Logistic growth model was applied to estimate the growth kinetic parameters (N0, λ, µmax, Nmax). The effect of storage temperature was modelled using the hyperbola (λ) and Ratkowsky (µmax) models. The simple Jameson-effect model, its modifications including the Ncri and the interaction γ factor, and the predator-prey Lotka Volterra model were used to characterize the interaction between both microorganisms. Two additional experiments at non-isothermal temperature conditions were also carried out to assess the predictive performance of the developed models through the Acceptable Simulation Zone (ASZ) approach. In monoculture conditions, L. monocytogenes and L. sakei CTC494 grew at all temperatures. In coculture conditions, L. sakei CTC494 had an inhibitory effect on L. monocytogenes by lowering the Nmax, especially with increasing levels of L. sakei CTC494 and lowering the storage temperature. At the lowest temperature (2 °C) L. sakei CTC494 was able to completely inhibit the growth of L. monocytogenes when added at a concentration 3 and 5 Log higher than that of the pathogen. The inhibitory effect of the L. sakei CTC494 against L. monocytogenes was properly characterized and modelled using the modified Jameson-effect with interaction γ factor model. The developed interaction model was tested under non-isothermal conditions, resulting in ASZ values ≥83%. This study shows the potential of L. sakei CTC494 in the biopreservation of vacuum-packaged cooked ham against L. monocytogenes. The developed interaction model can be useful for the industry as a risk management tool to assess and set biopreservation strategies for the control of L. monocytogenes in cooked ham.


Assuntos
Lactobacillus sakei , Listeria monocytogenes , Produtos da Carne , Contagem de Colônia Microbiana , Culinária , Microbiologia de Alimentos , Embalagem de Alimentos , Conservação de Alimentos , Modelos Teóricos , Temperatura , Vácuo
5.
Biomolecules ; 11(12)2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34944513

RESUMO

In the search for new biodegradable materials and greater microbiological safety and stability of perishable food products, this study aimed to develop a bioplastic antibacterial film incorporating bacteriocin for application in commercial curd cheese and monitoring of microbiological stability. Films with good handling characteristics as well as physical, barrier, and mechanical properties were obtained. Regarding the antibacterial activity, the microbial reduction was demonstrated in a food matrix, obtaining a reduction of 3 logarithmic cycles for the group of coagulase positive staphylococci and from 1100 to <3.00 MPN/g in the analysis of thermotolerant coliforms. Therefore, the film presented food barrier characteristics with the external environment and adequate migration of the antibacterial compound to the product, contributing to the reduction of contamination of a food with high initial microbial load.


Assuntos
Ágar/química , Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Embalagem de Alimentos/métodos , Lactobacillus sakei/química , Antibacterianos/química , Bacteriocinas/química , Queijo/microbiologia , Coagulase/metabolismo , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos , Tecnologia de Alimentos , Testes de Sensibilidade Microbiana , Staphylococcus/enzimologia
6.
Nutrients ; 13(11)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34836191

RESUMO

The potential of KDP, a lactic acid bacterial strain of Lactobacillus sakei, to enhance the production of mucosal specific immunoglobulin A (IgA) in mice and thereby enhance gut mucosal immunity was examined. KDP is composed of dead cells isolated from the Korean traditional food kimchi. Female BALB/c mice orally received 0.25 mg KDP once daily for 5 weeks and were co-administrated ovalbumin (OVA) for negative control and cholera toxin for positive control. Mice administered KDP exhibited increased secretory IgA (sIgA) contents in the small intestine, Peyer's patches, serum, colon, and lungs as examined by ELISA. KDP also significantly increased the gene expression of Bcl-6, IL-10, IL-12p40, IL-21, and STAT4. In addition, KDP acted as a potent antioxidant, as indicated by its significant inhibitory effects in the range of 16.5-59.4% for DPPH, nitric oxide, maximum total antioxidant capacity, and maximum reducing power. Finally, KDP exhibited potent antimicrobial activity as evidenced by a significant decrease in the growth of 7 samples of gram-negative and gram-positive bacteria and Candida albicans. KDP's adjuvant effect is shown to be comparable to that of cholera toxin. We conclude that KDP can significantly enhance the intestine's secretory immunity to OVA, as well as act as a potent antioxidant and antimicrobial agent. These results suggest that orally administered KDP should be studied in clinical trials for antigen-specific IgA production.


Assuntos
Anti-Infecciosos/farmacologia , Proteínas de Bactérias/farmacologia , Imunidade nas Mucosas/efeitos dos fármacos , Imunoglobulina A Secretora/efeitos dos fármacos , Mucosa Intestinal/imunologia , Lactobacillus sakei , Animais , Toxina da Cólera/farmacologia , Feminino , Intestino Delgado/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/farmacologia
7.
Biotechnol Lett ; 43(12): 2243-2257, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34652635

RESUMO

The biopreservation strategy allows extending the shelf life and food safety through the use of indigenous or controlled microbiota and their antimicrobial compounds. The aim of this work was to characterize an inhibitory substance with bacteriocin-like activity (Sak-59) produced by the potentially probiotic L. sakei strain from artisanal traditional Kazakh horse meat product Kazy. The maximum production of Sak-59 occurred at the stationary phase of the L. sakei growth. Sak-59 showed inhibitory activity against gram-positive meat spoilage bacteria strains of Listeria monocytogenes, Staphylococcus aureus, and pathogenic gram-negative bacteria strains of Serratia marcescens and Escherichia coli, but not against the tested Lactobacilli strains. Sak-59 activity, as measured by diffusion assay in agar wells, was completely suppressed after treatment with proteolytic enzymes and remained stable after treatment with α-amylase and lipase, indicating that Sak-59 is a peptide and most likely not glycosylated or lipidated. It was concluded that Sak-59 is a potential new bacteriocin with a characteristic activity spectrum, which can be useful in the food and feed industries.


Assuntos
Bacteriocinas/genética , Microbiologia de Alimentos , Lactobacillus sakei/química , Produtos da Carne/microbiologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Bacteriocinas/isolamento & purificação , Bacteriocinas/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Armazenamento de Alimentos , Cavalos/microbiologia , Humanos , Lactobacillus sakei/genética , Peptídeos/química , Peptídeos/farmacologia , Serratia marcescens/efeitos dos fármacos , Serratia marcescens/patogenicidade , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade
8.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638967

RESUMO

The objective of this work was to develop a chitosan/agar-agar bioplastic film incorporated with bacteriocin that presents active potential when used as food packaging. The formulation of the film solution was determined from an experimental design, through the optimization using the desirability function. After establishing the concentrations of the biopolymers and the plasticizer, the purified bacteriocin extract of Lactobacillus sakei was added, which acts as an antibacterial agent. The films were characterized through physical, chemical, mechanical, barrier, and microbiological analyses. The mechanical properties and water vapor permeability were not altered by the addition of the extract. The swelling property decreased with the addition of the extract and the solubility increased, however, the film remained intact when in contact with the food, thus allowing an efficient barrier. Visible light protection was improved by increased opacity and antibacterial capacity was effective. When used as Minas Frescal cream cheese packaging, it contributed to the increase of microbiological stability, showing a reduction of 2.62 log UFC/g, contributing a gradual release of the active compound into the food during the storage time. The film had an active capacity that could be used as a barrier to the food, allowing it to be safely packaged.


Assuntos
Antibacterianos/química , Bacteriocinas/química , Plásticos Biodegradáveis/química , Biopolímeros/química , Embalagem de Alimentos/métodos , Ágar/química , Materiais Biocompatíveis/química , Queijo/microbiologia , Quitosana/química , Temperatura Alta , Lactobacillus sakei/química , Lactobacillus sakei/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Permeabilidade , Extratos Vegetais/química , Plastificantes/química , Rodófitas/química , Solubilidade , Vapor
9.
J Microbiol Biotechnol ; 31(11): 1568-1575, 2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34528915

RESUMO

Obesity and related metabolic diseases are major problems worldwide. Some probiotics are currently considered potential therapeutic strategies for obesity. We aimed to investigate the antiobesity efficacy of Latilactobacillus sakei WIKIM31 in obese mice induced by a high fat diet. The administration of a high-fat diet with L. sakei WIKIM31 reduced body weight gain, epididymal fat mass, triglyceride and total cholesterol levels in the blood, and remarkably decreased the expression of lipogenesis-related genes in the epididymal adipose tissue and liver. Interestingly, intake of L. sakei WIKIM31 improved gut barrier function by increasing the gene expression of tight junction proteins and suppressing the inflammatory responses. Additionally, L. sakei WIKIM31 enhanced the production of short-chain fatty acids, such as butyrate and propionate, in the intestinal tract. These results showed that L. sakei WIKIM31 can be used as a potential therapeutic probiotic for obesity.


Assuntos
Inflamação/prevenção & controle , Lactobacillus sakei , Metabolismo dos Lipídeos , Obesidade/prevenção & controle , Probióticos , Aumento de Peso , Células 3T3-L1 , Tecido Adiposo/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Lipogênese , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos
10.
Int J Food Microbiol ; 355: 109335, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34343716

RESUMO

Latilactobacillus sakei group comprises four closely related species, making it difficult to accurately distinguish them with standard markers such as the 16S rRNA gene. The objective of our study was to mine novel markers for PCR detection and discrimination of L. sakei group species and L. sakei subspecies by comparative pan-genomic analysis. A total of 63 genome sequences of L. sakei group species consisted of 119,899 coding genes, yielding 5741 pan-genomes, 831 core-genomes, 3347 accessory-genomes, and 1563 unique-genomes. The accessory-genome was compared to extract unique candidate genes common only to genomes of the same species. The candidate genes were then aligned with the other bacterial genomes to select marker genes present in all genomes of a given species, but not in the genomes of other species. We identified the arginine/ornithine antiporter, putative cell surface protein precursor, sodium:solute symporter, PRD domain protein, PTS sugar transporter subunit IIC, and phosphoenolpyruvate-dependent sugar phosphotransferase system EIIC as marker genes for L. sakei, L. sakei subsp. sakei, L. sakei subsp. carnosus, L. curvatus, L. graminis, and L. fuchuensis, respectively. Primer pairs were designed for each marker and showed 100% specificity for 48 lactic acid bacterial reference strains. The PCR method developed in this study was used to evaluate 106 strains isolated from fermented foods to demonstrate that the marker genes provided a viable alternative to the 16S rRNA gene. We also applied the method to the monitoring of kimchi samples to quantify L. sakei group species or subspecies. Our PCR method based on novel markers can rapidly identify L. sakei group with high accuracy and high throughput.


Assuntos
Biologia Computacional , Lactobacillus sakei , Reação em Cadeia da Polimerase em Tempo Real , /microbiologia , Marcadores Genéticos/genética , Lactobacillus sakei/genética , RNA Ribossômico 16S/genética
11.
Artigo em Inglês | MEDLINE | ID: mdl-34281032

RESUMO

Dry-cured sausages are traditional in Mediterranean countries, and Paio do Alentejo (PA) is one of the most popular in South Portugal. The aim of the present work was to evaluate the effect of combined starters on the safety and quality of PA preserving its sensory quality. Physicochemical parameters, namely pH and water activity (aW), microbiological parameters, biogenic amines, color, texture, and sensory attributes were assessed. Three starter cultures were used, namely Staphylococcus equorum S2M7 and Lactobacillus sakei CV3C2, both separate and combined with the 2RB4 yeast strain at a concentration of 106 cfu/g. Dextrose 0.25% was added to the meat batter. Starters had a significant effect on the reduction of aW values (0.845 to 0.823). The treatment with L. sakei as well as the co-inoculation of L. sakei with S. equorum effectively reduced the L. monocytogenes counts to undetectable levels. Sausages co-inoculated with S. equorum S2M7/L. sakei CV3C2 showed a significant reduction in the content of vasoactive amines, namely tryptamine (26.21 to 15.70) and ß-phenylethylamine (4.80 to 3.69). Regarding texture, control PA showed higher hardness values, and the starters promoted the cohesiveness of the batter while reducing chewiness. The studied starters did not compromise the sensory characteristics of PA.


Assuntos
Lactobacillus sakei , Produtos da Carne , Aminas Biogênicas , Fermentação , Microbiologia de Alimentos , Produtos da Carne/análise , Portugal , Staphylococcus
12.
J Ethnopharmacol ; 280: 114448, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34303805

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Milk production, processing and consumption are integral part of traditional practices in Fulani tribe of Cameroon. It has been observed that Fulani are resistant to malaria. Dairy products traditionally processed by Fulani are intensively used in the ritual treatment of malarial, inflammations and behavioural disorders. Many studies have demonstrated that fermented milk is a rich source of probiotic bacteria. However, the antimalarial activity of probiotics isolated from this natural source has not been experimentally tested. AIM OF THE STUDY: Hence, this study was therefore aimed at evaluating the antimalarial activity of a probiotic bacterium Lactobacillus sakei isolated from traditionally fermented milk in mice infected with chloroquine sensitive Plasmodium berghei ANKA. MATERIALS AND METHODS: The probiotic bacterium was isolated from the Cameroonian Mborro Fulani's traditionally fermented milk and identified using the 16S r RNA gene sequencing. The schizontocidal activity of Lactobacillus sakei on established malaria infection was evaluated. Eighty-four healthy young adult Balb/c mice infected with Plasmodium berghei parasite were randomly divided into two sets of seven group of six mice each, and were given three different doses of Lactobacillus sakei, chloroquine and sulfadoxine/pyrimethamine for seven and fourteen days respectively. The level of parasitaemia, body temperature, survival time and haematological parameters were evaluated. RESULTS: The parasite growth inhibition was observed to increase with increasing dose of probiotic bacterium with maximum suppression being 100 % at dose 3 on day 20. Also, the probiotic bacterium significantly prevented body weight loss and was associated with body temperature reduction and prevented (p<0.05) a decrease in haematological parameters compared to that untreated malaria infected mice. CONCLUSION: The results obtained suggest that Lactobacillus sakei is a probiotic bacterium with antimalarial activity in mice infected with chloroquine sensitive Plasmodium berghei.


Assuntos
Antimaláricos/farmacologia , Lactobacillus sakei , Malária/terapia , Plasmodium berghei/efeitos dos fármacos , Probióticos/farmacologia , Animais , Antimaláricos/administração & dosagem , Camarões , Cloroquina/farmacologia , Modelos Animais de Doenças , Combinação de Medicamentos , Malária/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Leite/microbiologia , Parasitemia/parasitologia , Parasitemia/terapia , Probióticos/administração & dosagem , Pirimetamina/farmacologia , Sulfadoxina/farmacologia
13.
Food Microbiol ; 99: 103829, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119114

RESUMO

The endogenous microflora of mussels, filter feeders, can include pathogens with resulting food safety concerns. The aim was to develop a cook-then-ferment technology to extend shelf life and safety of a ready-to-eat mussels. Only after cooking to destroy the mussel's endogenous microflora could an edible product be made as determined by pH decline after fermentation and the fate of common pathogens. Perna canaliculus was bought live at retail on many dates. Fermentation was with commercial lactic cultures incubated under vacuum at 30 °C for four days. Using one culture containing Pediococcus pentosaceus and Staphylococcus carnosus as a model, pH typically declined to 4.5 to 4.7, and common pathogens, Staphylococcus aureus, Salmonella and Vibrio parahaemolyticus were absent or reduced to acceptable levels. The fate of Listeria monocytogenes was studied with five cultures. These were variably effective at inhibition with one clear success, Chr Hansen's T-SC-150 containing a specific strain of Lactobacillus sakei, and flavour-generating Staphylococcus carnosus. This culture's efficacy was confirmed with sterile extracts of LAB challenging L. monocytogenes in vitro. This culture was also the most rapid fermenter by pH fall. Cook-then-ferment technology may be applied to other novel foods to minimise a disruptive endogenous microflora.


Assuntos
Manipulação de Alimentos/métodos , Lactobacillales/metabolismo , Perna (Organismo)/microbiologia , Frutos do Mar/microbiologia , Animais , Culinária , Fast Foods/microbiologia , Fermentação , Lactobacillus sakei/metabolismo , Listeria monocytogenes/crescimento & desenvolvimento , Perna (Organismo)/química , Frutos do Mar/análise , Staphylococcus aureus/crescimento & desenvolvimento
14.
Microbiol Spectr ; 9(1): e0007421, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34190593

RESUMO

Obesity is a major public health problem related to various chronic health conditions. Lactobacillus species has been reported in obese individuals; however, its role is unknown. We compared the abundance and composition of Lactobacillus species by analyzing feces from 64 healthy control subjects and 88 obese subjects. We isolated one Lactobacillus strain from the feces of a subject with obesity and further analyzed its genetic and molecular features. We found that an increased abundance and higher prevalence of Lactobacillus sakei distinguished the fecal microbiota of the obese group from that of healthy subjects and that it was related to the increased levels of reactive oxygen species (ROS) induced by higher fat intake. The L. sakei ob4.1 strain, isolated from the feces of a subject with obesity, showed high catalase activity, which was regulated by oxidative stress at the gene transcription level. L. sakei ob4.1 maintained colon epithelial cell adhesion ability under ROS stimulation, and treatment with saturated fatty acid increased colon epithelial ROS levels in a dose-dependent manner; however, L. sakei ob4.1 did not change the level of fat-induced colon epithelial ROS. Exposing mice to a high-fat diet revealed that high-fat-diet-induced colon ROS was associated with the increased colonization of L. sakei ob4.1 through catalase activity. Four-week supplementation with this strain in mice fed a high-fat diet did not change their body weights or ROS levels. A high-fat diet induces changes in the colon environment by increasing ROS levels, which provides a colonization benefit to an L. sakei strain with high catalase activity. IMPORTANCE Lactobacillus provides many health benefits; its various species are widely used as probiotics. However, an increased abundance of Lactobacillus has been reported in obesity, and the role of Lactobacillus strains in obesity remains unknown. We found a high abundance of the Lactobacillus sakei species in a group of obese subjects and examined its relationship with a high-fat diet and reactive oxygen species (ROS) in the feces. To find the underlying mechanism, we analyzed and characterized an L. sakei strain isolated from a severely obese individual. We found that higher gut oxidative stress could link high-fat-diet-induced obesity and L. sakei. This translational research identifies the roles of the host gut environment in the colonization and survival of L. sakei.


Assuntos
Lactobacillus sakei/crescimento & desenvolvimento , Obesidade/microbiologia , Estresse Oxidativo , Animais , Colo/metabolismo , Colo/microbiologia , Dieta Hiperlipídica/efeitos adversos , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal , Humanos , Lactobacillus/classificação , Lactobacillus/genética , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/isolamento & purificação , Lactobacillus sakei/genética , Lactobacillus sakei/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Espécies Reativas de Oxigênio/metabolismo
15.
Transl Vis Sci Technol ; 10(6): 8, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-34111255

RESUMO

Purpose: The study investigates the regulatory effects exhibited by lysate of Lactobacillus sakei pro-Bio65 (4%; L.SK) on the human conjunctival epithelial (HCE) cell line. Methods: Trypan blue and methylthiazol tetrazolium (MTT) methods were used to assess cell growth and viability. Mitochondrial membrane potential was assessed by JC-1 staining and cytofluorimetric detection methods. The antioxidant pattern and the intracellular reactive oxygen species (ROS) levels were analyzed by spectrophotometric and spectrofluorimetric methods. NF-κB luciferase activity was quantified by luminometric detection. NF-κB nuclear translocation, as well as mitochondrial morphology, were investigated by immunofluorescence using confocal microscopy. Cytokines and COX2 expression levels were determined by Western blot analyses. Results: This study demonstrates that L.SK exposure does not influence HCE cell proliferation and viability in vitro. L.SK paraprobiotic induces mild-low levels of intracellular ROS. It is coupled to changes in the mitochondrial membrane potential (ΔΨm), in a context of a regular mitochondrial-network organization. The negative modulation of tumor necrosis factor alpha (TNF-α) expression levels and rising antioxidant defense efficiency, mediated by the upregulation of glutathione (GSH) and increased antioxidant enzymatic activities, were observed. Conclusions: This study demonstrates that L.SK empowers the antioxidant endogenous efficiency of HCE cells, by the upregulation of the GSH content and the enzymatic antioxidant pattern, and concurrently reduces TNF-α protein expression. Translational Relevance: Although the obtained in vitro results should be confirmed by in vivo investigations, our data suggest the possibility of L.SK paraprobiotic application for promoting eye health, exploring its use as an endogen antioxidant system inducer in preventing and treating different oxidative stress-based, inflammatory, and age-related conditions.


Assuntos
Lactobacillus sakei , Fator de Necrose Tumoral alfa , Antioxidantes , Glutationa/metabolismo , Humanos , Lactobacillus sakei/metabolismo , Estresse Oxidativo , Fator de Necrose Tumoral alfa/metabolismo
16.
Meat Sci ; 180: 108584, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34087663

RESUMO

In this work, Italian salami were produced using microbial starters (Pediococcus pentosaceus, Lactobacillus sakei, and Staphylococcus xylosus) and compared to a control sample (without starter). Metabolomics in combination with microbiological and sensory analyses were used to investigate the overall quality. Samples were analyzed immediately after stuffing, following 7, 30, and 45 days of ripening. Each microbial starter imposed distinctive metabolomic signatures at the end of ripening. The accumulated discriminant compounds were mainly related to lipid oxidation (including hydroxy- and epoxy derivatives of fatty acids) following the inoculation with L. sakei. However, the inoculation with P. pentosaceus resulted in the accumulation of γ-glutamyl peptides, compounds driving a kokumi-related taste. Noteworthy, our findings supported the involvement of the chemical compounds profiled in the definition of final taste and aroma. This information paves the way towards the definition of more objective and tailored starters-related flavours enhancement approaches in the sector of cured meat.


Assuntos
Manipulação de Alimentos/métodos , Produtos da Carne/análise , Produtos da Carne/microbiologia , Animais , Fermentação , Microbiologia de Alimentos , Humanos , Lactobacillus sakei , Lipídeos/análise , Odorantes , Oxirredução , Pediococcus pentosaceus , Staphylococcus , Sus scrofa , Paladar
17.
Biosci Biotechnol Biochem ; 85(6): 1536-1545, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-33885732

RESUMO

We analyzed the mechanisms underlying enhanced IgA production in the cells of Peyer's patch cells via membrane vesicles derived from Lactobacillus sakei subsp. sakei NBRC 15893. Depletion of CD11c+ cells from Peyer's patch cells suppressed the enhanced IgA production mediated by membrane vesicles. Meanwhile, the stimulation of bone-marrow-derived dendritic cells with membrane vesicles increased gene expression of inducible nitric oxide synthase, retinaldehyde dehydrogenase 2, and several inflammatory cytokines. The production of nitric oxide and interleukin (IL)-6 by membrane vesicle stimulation was induced via Toll-like receptor 2 on bone marrow-derived dendritic cells. Inhibition of inducible nitric oxide synthase and retinaldehyde dehydrogenase 2, as well as the neutralization of IL-6 in Peyer's patch cells, suppressed the enhanced IgA production by membrane vesicle stimulation. Hence, nitric oxide, retinoic acid, and IL-6 induced by membrane vesicles play crucial roles in the enhanced IgA production elicited by membrane vesicles in Peyer's patch cells.


Assuntos
Membrana Celular/metabolismo , Imunoglobulina A/biossíntese , Lactobacillus sakei/citologia , Nódulos Linfáticos Agregados/metabolismo , Nódulos Linfáticos Agregados/citologia
18.
Appl Environ Microbiol ; 87(6)2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33452026

RESUMO

Kimoto-style seed mash is a traditional preparation method for sake that takes advantage of spontaneous lactic acid fermentation before the growth of yeast. Lactic acid helps decrease the pH in seed mash and control the growth of unfavorable microorganisms. In this study, we carried out a comprehensive analysis of the change in the bacterial community and chemical composition during the lactic acid fermentation stage in kimoto-style seed mash preparation. The bacterial transitions were diverse at five sake breweries, but they exhibited three patterns. Lactobacillus sakei was the dominant species in the later stage of lactic acid fermentation in all sake breweries. This species was found to be the most important bacterium for the accumulation of lactic acid, because its average production rate of lactic acid in seed mash reached 4.44 × 10-11 mg cell-1 h-1, which is 10 times higher than those of other species. As a result of specific growth rate analysis, it was revealed that the growth rate of L. sakei was influenced by the strain, pH, and temperature. The effects of pH and temperature were explained by the square root model, and the result indicates that the strains isolated in this study were incapable of growth below pH 3.9. The growth curve predicted using the growth model fit the actual cell density in two out of five sake breweries; however, our model did not work well for the remaining three sake breweries, and we presume that the error was caused by the strain or an unknown factor.IMPORTANCE It is important to produce lactic acid in kimoto-style seed mash; however, the bacterial transition is different depending on the sake brewery. The reason why there are diverse bacterial transitions during kimoto-style seed mash preparation for each sake brewery is unclear so far, and it causes difficulty in starting kimoto-style seed mash. Our findings indicate that the changes in pH caused by lactic acid bacteria grown prior to L. sakei in seed mash influence the growth of L. sakei and are related to the diversity of the bacterial transition. This study uses comprehensive analytical methods to reveal that there is a diversity of bacterial transition and chemical compositions in kimoto-style seed mash depending on the sake brewery and to explain the differences in bacterial transition depending on the characteristics of L. sakei.


Assuntos
Bebidas Alcoólicas , Ácido Láctico/metabolismo , Lactobacillus sakei/crescimento & desenvolvimento , Lactobacillus sakei/metabolismo , Arginina/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , Temperatura
19.
World J Microbiol Biotechnol ; 37(2): 31, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33458785

RESUMO

Spheroids of intestinal cells (Caco-2) were used to evaluate the adhesion/invasion ability of Listeria monocytogenes (pathogen) and Lactobacillus sakei 1 (potential probiotic). Besides, transcriptomic analyses of Caco-2 cells in three dimensional cultures were done, with the aim of revealing possible host-foodborne bacteria interactions. Result of adhesion assay for L. monocytogenes in Caco-2 spheroids was 22.86 ± 0.33%, but it was stimulated in acidic pH (4.5) and by the presence of 2% sucrose (respectively, 32.56 ± 1.35% and 33.25 ± 1.26%). Conversely, the invasion rate of L. monocytogenes was lower at pH 4.5, in comparison with non-stressed controls (18.89 ± 1.05% and 58.65 ± 0.30%, respectively). L. sakei 1 adhered to Caco-2 tridimensional cell culture (27.30 ± 2.64%), with no invasiveness. There were 19 and 21 genes down and upregulated, respectively, in tridimensional Caco-2 cells, upon infection with L. monocytogenes, which involved immunity, apoptosis; cytoprotective responses, cell signalling-regulatory pathways. It was evidenced despite activation or deactivation of several pathways in intestinal cells to counteract infection, the pathogen was able to hijack many host defense mechanisms. On the other hand, the probiotic candidate L. sakei 1 was correlated with decreased transcription of two genes in Caco-2 cells, though it stimulated the expression of 14 others, with diverse roles in immunity, apoptosis, cytoprotective response and cell signalling-regulatory pathways. Our data suggest the use of tridimensional cell culture to mimic the intestinal epithelium is a good model for gathering broad information on the putative mechanisms of interaction between host and bacteria of importance for food safety, which can serve as a basis for further in-depth investigation.


Assuntos
Técnicas de Cultura de Células/métodos , Intestinos/citologia , Lactobacillus sakei/fisiologia , Listeria monocytogenes/fisiologia , Aderência Bacteriana , Reatores Biológicos/microbiologia , Células CACO-2 , Proliferação de Células , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Intestinos/química , Intestinos/microbiologia , Probióticos/farmacologia , Esferoides Celulares/química , Esferoides Celulares/citologia
20.
Colloids Surf B Biointerfaces ; 197: 111387, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33049659

RESUMO

Alginate microspheres loaded with two fermentation active agents, calcium cations and strain LS0296 identified as Lactobacillus sakei, have been prepared and characterized. The role of calcium cation is twofold, it acts as gelling cation and as fermentation active agent. Encapsulation and the presence of calcium ions in the same compartment do not inhibit the activity of LS0296. Molecular interactions in microspheres are complex, including mainly hydrogen bonds and electrostatic interactions. In vitro calcium cations and strain LS0296 release profiles were fitted to the Korsmeyer-Peppas empirical model. The calcium cation release process is driven at first by Fickian diffusion through microspheres and then by anomalous transport kinetics. The in vitro LS0296 release process is driven by Fickian diffusion through microspheres showing a much slower releasing rate than calcium cations. The release of LS0296 strain is followed by a decrease in the pH value. Results obtained give us a new insight into complex interactions between bacterial cultures and microsphere constituents. Prepared formulations of calcium alginate microspheres loaded with LS0296 could be used as a new promising tool and a model for different starter cultures encapsulation and use in the production of fermented foods.


Assuntos
Lactobacillus sakei , Alginatos , Cálcio , Fermentação , Ácido Glucurônico , Íons , Microesferas
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