Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 471
Filtrar
1.
Meat Sci ; 183: 108661, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34467880

RESUMO

The increasing concern of consumers about food quality and safety and their rejection of chemical additives has promoted the breakthrough of the biopreservation field and the development of studies on the use of beneficial bacteria and their metabolites as potential natural antimicrobials for shelf life extension and enhanced food safety. Control of foodborne pathogens in meat and meat products represents a serious challenge for the food industry which can be addressed through the intelligent use of bio-compounds or biopreservatives. This article aims to systematically review the available knowledge about biological strategies based on the use of lactic acid bacteria to control the proliferation of undesirable microorganisms in different meat products. The outcome of the literature search evidenced the potential of several strains of lactic acid bacteria and their purified or semi-purified antimicrobial metabolites as biopreservatives in meat products for achieving longer shelf life or inhibiting spoilage and pathogenic bacteria, especially when combined with other technologies to achieve a synergistic effect.


Assuntos
Conservação de Alimentos/métodos , Lactobacillales/fisiologia , Produtos da Carne/microbiologia , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bacteriocinas/farmacologia , Microbiologia de Alimentos , Lactobacillales/metabolismo , Produtos da Carne/análise
2.
Molecules ; 26(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34641607

RESUMO

The application of bacterial cultures in food fermentation is a novel strategy to increase the "natural" levels of bioactive compounds. The unique ability of lactic acid bacteria (LAB) to produce folate, B vitamins, and conjugated linolenic acid cis9trans11 C18:2 (CLA) during cold storage up to 21 days was studied. Although some species of LAB can produce folates and other important nutrients, little is known about the production ability of yogurt starter cultures. Pasteurized milk samples were inoculated with four different combinations of commercially available yogurt vaccines, including starter cultures of Bifidobacterium bifidum. Both the type of vaccine and the time of storage at 8 °C had a significant effect on the folate and CLA contents in the tested fermented milks. The highest folate content (105.4 µg/kg) was found in fresh fermented milk inoculated with Lactobacillus delbrueckii, Streptococcus thermophilus, and Bifidobacterium bifidum. Only the mix of Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, and Bifidobacterium bifidum showed potential (59% increase) to synthesize folate during seven days of storage. A significant increase in the content of CLA, when compared to fresh fermented milk, was observed during cold storage for up to 21 days in products enriched with Bifidobacterium bifidum.


Assuntos
Produtos Fermentados do Leite/microbiologia , Ácido Fólico/metabolismo , Lactobacillales/metabolismo , Ácidos Linoleicos Conjugados/metabolismo , Leite/metabolismo , Leite/microbiologia , Complexo Vitamínico B/metabolismo , Animais , Bifidobacterium bifidum/metabolismo , Biofortificação/métodos , Fermentação , Microbiologia de Alimentos , Lactobacillus delbrueckii/metabolismo , Probióticos , Streptococcus thermophilus/metabolismo , Fatores de Tempo
3.
Molecules ; 26(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34641608

RESUMO

The effect of spontaneous fermentation by lactic acid bacteria on the extraction yield of bioactive compounds and antioxidant activity from rosemary leaf extracts was investigated using high-performance thin-layer chromatography (HPTLC). Brining and spontaneous fermentation with lactic acid bacteria more than doubled extraction of polyphenolics and antioxidants from the rosemary leaves. The results show that lactic acid fermentation enhances antioxidant activity in extracts by increasing the total phenolic content but does not increase extraction of phytosterols. Increased extraction of phenolic oxidants during fermentation assisted extraction, results from the in situ generated natural eutectic solvent from the plant sample. ATR-FTIR spectra from the bioactive bands suggests that this increased antioxidant activity is associated with increased extraction of rosmarinic acid, depolymerised lignin, abietane diterpenoids and 15-hydroxy-7-oxodehydroabietic acid.


Assuntos
Antioxidantes/química , Antioxidantes/metabolismo , Lactobacillales/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Rosmarinus/química , Rosmarinus/metabolismo , Abietanos/química , Abietanos/metabolismo , Cromatografia em Camada Delgada , Cinamatos/química , Cinamatos/metabolismo , Depsídeos/química , Depsídeos/metabolismo , Fermentação , Humanos , Lignina/química , Lignina/metabolismo , Fenóis/química , Fenóis/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
4.
J Food Sci ; 86(9): 4172-4182, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34333773

RESUMO

The objective of this study was to develop probiotic beverages, enriched with plant proteins, with high nutritional value. A rice-based beverage fermented with a specific probiotic formulation comprised Lactobacillus acidophilus CL1285, Lactobacillus casei LBC80R and Lactobacillus rhamnosus CLR2 has been enriched with a combination of pea and rice proteins (PR) or pea and hemp proteins (PH) at 13 and 11% total protein, respectively. These protein associations have been selected because their amino acid ratio was >1, as recommended by the FAO. The beverage enriched with protein significantly increased its viscosity by more than 10 times thanks to the enrichment, while the fermentation reduced it by 50% for PR and 20% for PH. In vitro protein digestibility results showed that the protein enrichment and the fermentation treatment significantly increased digestibility values of the beverages with value of 72.7% for fermented PR beverage and 61.4% for unenriched fermented control beverage (p ≤ 0.05). Peptide profiles of PR and PH enriched beverages indicated that the fermentation led to a reduced level of high molecular weight (HMW) peptides of about 60% and an increase of low molecular weight (LMW) peptides by over 50%. Therefore, both the fermentation and the enrichment in protein increased the nutritional value of the rice-based beverages. PRACTICAL APPLICATION: Good quality of probiotics formulation and high-protein products are in increasing demand and plant proteins as an alternative of animal protein are popular. This study has permit to develop rice-based commercial probiotic beverages enriched in a combination of pea and rice or pea and hemp proteins in order to obtain a complete protein in terms of amino acids composition. The lactic acid fermentation and the enrichment with a plant protein combination led to a better protein digestibility of beverage.


Assuntos
Microbiologia de Alimentos , Alimentos Fortificados , Lactobacillales , Proteínas de Plantas , Probióticos , Animais , Alimentos Fortificados/análise , Alimentos Fortificados/microbiologia , Lactobacillales/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo
5.
Appl Environ Microbiol ; 87(20): e0105521, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34347516

RESUMO

Nutritional dependencies, especially those regarding nitrogen sources, govern numerous microbial positive interactions. As for lactic acid bacteria (LAB), responsible for the sanitary, organoleptic, and health properties of most fermented products, such positive interactions have previously been studied between yogurt bacteria. However, they have never been exploited to create artificial cocultures of LAB that would not necessarily coexist naturally, i.e., from different origins. The objective of this study was to promote LAB positive interactions, based on nitrogen dependencies in cocultures, and to investigate how these interactions affect some functional outputs, e.g., acidification rates, carbohydrate consumption, and volatile-compound production. The strategy was to exploit both proteolytic activities and amino acid auxotrophies of LAB. A chemically defined medium was thus developed to specifically allow the growth of six strains used, three proteolytic and three nonproteolytic. Each of the proteolytic strains, Enterococcus faecalis CIRM-BIA2412, Lactococcus lactis NCDO2125, and CIRM-BIA244, was cocultured with each one of the nonproteolytic LAB strains, L. lactis NCDO2111 and Lactiplantibacillus plantarum CIRM-BIA465 and CIRM-BIA1524. Bacterial growth was monitored using compartmented chambers to compare growth in mono- and cocultures. Acidification, carbohydrate consumption, and volatile-compound production were evaluated in direct cocultures. Each proteolytic strain induced different types of interactions: strongly positive interactions, weakly positive interactions, and no interactions were seen with E. faecalis CIRM-BIA2412, L. lactis NCDO2125, and L. lactis CIRM-BIA244, respectively. Strong interactions were associated with higher concentrations of tryptophan, valine, phenylalanine, leucine, isoleucine, and peptides. They led to higher acidification rates, lower pH, higher raffinose utilization, and higher concentrations of five volatile compounds. IMPORTANCE Interactions of lactic acid bacteria (LAB) are often studied in association with yeasts or propionibacteria in various fermented food products, and the mechanisms underlying their interactions are being quite well characterized. Concerning interactions between LAB, they have mainly been investigated to test antagonistic interactions. Understanding how they can positively interact could be useful in multiple food-related fields: production of fermented food products with enhanced functional properties or fermentation of new food matrices. This study investigated the exploitation of the proteolytic activity of LAB strains to promote positive interactions between proteolytic and nonproteolytic strains. The results suggest that proteolytic LAB do not equally stimulate nonproteolytic LAB and that the stronger the interactions between LAB are, the more functional outputs we can expect. Thus, this study gives insight into how to create new associations of LAB strains and to guarantee their positive interactions.


Assuntos
Lactobacillales/metabolismo , Interações Microbianas , Nitrogênio/metabolismo , Aminoácidos/metabolismo , Animais , Técnicas de Cocultura , Microbiologia de Alimentos , Lactobacillales/crescimento & desenvolvimento , Lactose/metabolismo , Lupinus , Leite , Peptídeos , Proteólise , Rafinose/metabolismo , Sacarose/metabolismo , Compostos Orgânicos Voláteis/metabolismo
6.
Food Microbiol ; 100: 103868, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34416967

RESUMO

Kimchi is one of the primary sources of high sodium content in the Korean diet. Low-sodium kimchi is commercially manufactured to minimize the health effects of high salt. We investigated the influence of lactic acid bacteria (LAB) as starter culture in combination with 1% or 2.5% salt on the survival of pathogenic Escherichia coli and physicochemical properties of kimchi during fermentation at 10 °C and 25 °C. Among ten strains of LAB isolated from kimchi, Leuconostoc mesenteroides (KCTC 13374) and Lactobacillus plantarum (KCTC 33133) exhibited antimicrobial activities against pathogenic E. coli (EPEC, ETEC, and E. coli O157:H7) and strong tolerance to low pH (2 and 3) and 0.3% bile salts. Thus, L. mesenteroides and L. plantarum were used as starter cultures for kimchi that contained 1% and 2.5% salt. All pathogenic E. coli strains survived in kimchi regardless of starter cultures or salt concentration for over 15 days at 10 °C, but they died off within 4 days at 25 °C. Survival of pathogenic E. coli was better in naturally fermented kimchi (titratable acidity:0.65%) than kimchi fermented with starter cultures (titratable acidity:1.0%). At 10 °C, the average delta value of E. coli O157:H7 (16.15 d) was smaller than those of EPEC (20.76 d) and ETEC (20.20 d) in naturally fermented kimchi. Overall, survival ability of E. coli O157:H7 was lower than EPEC and ETEC, although differences were not significant. Reduced salt concentration from 2.5% to 1% in kimchi did not affect the growth of LAB and the fermentation period. Pathogenic E. coli died at a faster rate in kimchi fermented with starter cultures and 1% salt than in naturally fermented kimchi with 2.5% salt.


Assuntos
Brassica/microbiologia , Escherichia coli Enteropatogênica/crescimento & desenvolvimento , Escherichia coli Enterotoxigênica/crescimento & desenvolvimento , Escherichia coli O157/crescimento & desenvolvimento , Lactobacillales/metabolismo , Cloreto de Sódio/metabolismo , Antibiose , Brassica/química , Contagem de Colônia Microbiana , Escherichia coli Enteropatogênica/fisiologia , Escherichia coli Enterotoxigênica/fisiologia , Escherichia coli O157/fisiologia , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Cloreto de Sódio/análise
7.
Nutrients ; 13(8)2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34444949

RESUMO

The prevalence of gastritis in humans is constantly growing and a prediction of an increase in this health problem is observed in many countries. For this reason, effective dietary therapies are sought that can alleviate the course of this disease. The objective of this study was to determine the effect of chemically pure oat beta-glucan preparations with different molar masses, low or high, used for 30 days in patients with histologically diagnosed chronic gastritis. The study enrolled 48 people of both genders of different ages recruited from 129 patients with a gastritis diagnosis. Before and after the therapy, hematological, biochemical, immunological and redox balance parameters were determined in the blood and the number of lactic acid bacteria and SCFA concentrations in the feces. Our results demonstrated a beneficial effect of oat beta-glucans with high molar mass in chronic gastritis in humans, resulting in reduced mucosal damage and healthy changes in SCFA fecal concentration and peripheral blood serum glutathione metabolism and antioxidant defense parameters. This fraction of a highly purified oat beta-glucan is safe for humans. Its action is effective after 30 days of use, which sheds new light on the nutritional treatment of chronic gastritis.


Assuntos
Avena , Gastrite/dietoterapia , beta-Glucanas/administração & dosagem , Adulto , Idoso , Doença Crônica , Método Duplo-Cego , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Fezes/microbiologia , Feminino , Gastrite/microbiologia , Humanos , Lactobacillales/metabolismo , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Resultado do Tratamento , Adulto Jovem
8.
World J Microbiol Biotechnol ; 37(8): 143, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34328568

RESUMO

Antifungal and antibacterial activities of twenty-six combinations of lactic acid bacteria, propionibacteria, acetic acid bacteria and dairy yeasts inoculated in whey and milk were investigated. Associations including acetic acid bacteria were shown to suppress growth of the opportunistic yeast Candida albicans in well-diffusion assays. The protective effect of milk fermented with the two most promising consortia was confirmed in Caco-2 cell culture infected with C. albicans. Indeed, these fermented milks, after heat-treatment or not, suppressed lactate dehydrogenase release after 48 h while significant increase in LDH release was observed in the positive control (C. albicans alone) and with fermented milk obtained using commercial yogurt starter cultures. The analysis of volatile compounds in the cell-free supernatant using solid phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS) showed accumulation of significant amount of acetic acid by the consortium composed of Lactobacillus delbrueckii 5, Lactobacillus gallinarum 1, Lentilactobacillus parabuchneri 3, Lacticaseibacillus paracasei 33-4, Acetobacter syzygii 2 and Kluyveromyces marxianus 19, which corresponded to the zone of partial inhibition of C. albicans growth during well-diffusion assays. Interestingly, another part of anti-Candida activity, yielding small and transparent inhibition zones, was linked with the consortium cell fraction. This study showed a correlation between anti-Candida activity and the presence of acetic acid bacteria in dairy associations as well as a significant effect of two dairy associations against C. albicans in a Caco-2 cell model. These two associations may be promising consortia for developing functional dairy products with antagonistic action against candidiasis agents.


Assuntos
Candida/crescimento & desenvolvimento , Produtos Fermentados do Leite/microbiologia , Lactobacillales/metabolismo , Leite/microbiologia , Animais , Antibiose , Células CACO-2 , Bovinos , Produtos Fermentados do Leite/análise , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactobacillales/química , Lactobacillales/classificação , Leite/química
9.
Molecules ; 26(14)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34299468

RESUMO

Inoculation of sourdough allows the fermentation medium to be dominated by desired microorganisms, which enables determining the kinetics of the conversion of chemical compounds by individual microorganisms. This knowledge may allow the design of functional food products with health features dedicated to consumers with special needs. The aim of the study was to assess the dynamics of transformations of fermentable oligosaccharide, disaccharide, monosaccharide and polyol (FODMAP) compounds from wheat flour as well as their antioxidant activity during inoculated and spontaneous sourdough fermentation. The FODMAP content in grain products was determined by the fructan content with negligible amounts of sugars and polyols. To produce a low-FODMAP cereal product, the fermentation time is essential. The 72 h fermentation time of L. plantarum-inoculated sourdough reduced the FODMAP content by 91%. The sourdough fermentation time of at least 72 h also positively influenced the content of polyphenols and antioxidant activity, regardless of the type of fermentation. The inoculation of both L. plantarum and L. casei contributed to a similar degree to the reduction in FODMAP in sourdough compared to spontaneous fermentation.


Assuntos
Antioxidantes/metabolismo , Farinha/análise , Ácido Láctico/metabolismo , Lactobacillales/metabolismo , Polímeros/metabolismo , Polifenóis/metabolismo , Triticum/metabolismo , Carboidratos/química , Fermentação , Lactobacillales/crescimento & desenvolvimento , Triticum/microbiologia
10.
Curr Microbiol ; 78(9): 3430-3438, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34255153

RESUMO

An attempt was made, to characterize natural antibiotics or lantibiotics from unconventional sources and its antibacterial spectrum against food borne pathogens and drug resistant bacteria. Six different traditional fermented foods i.e., fermented fish, fermented soybeans, Soibum (fermented bamboo shoots), milk, idly and dosa batter were used for the isolation of bacteriocin producing Lactic acid bacteria (LAB). Among all bacterial cultures isolated from the various sources, 129 cultures have found to produce antimicrobial compounds. Nisin specific reporter bacteria was utilized as biosensor to identify the Nisin like bacteriocin, where 10 cultures found to be positive Nisin producer. Identified Nisin like bacteriocin was partially concentrated by using ammonium sulphate followed by butanol extraction. Minimum inhibitory concentration (MIC) was analyzed against food borne pathogen and drug resistant bacteria. MIC of partially purified Nisin (pp-Nisin) of all the LAB isolates against food-borne pathogens are ranged between 0.5 and 92 µg/ml respected to various Gram-positive bacteria. Similarly, the drug resistant bacteria were also inhibited by pp-Nisin (MIC ranged between 15 and 175 µg/ml). All samples of ppnisin exhibited auto induction ability. Taxonomic identification of the nisin producers was done by whole genome sequencing which reveals that cultures belongs to Lactococcus lactis ssp. lactis. Also it was found that Lactococcus lactis ssp. lactis C2d and Lactococcus lactis ssp. lactis SP2C4 harbor nisA gene and Lactococcus lactis ssp. lactis FS2 (L. lactis FS2) harbor nisQ gene. The finding of this study highlights the first case of L. lactis FS2 isolated from fermented fish harbor nisQ gene. Antibacterial activity of pp-Nisin against drug resistant LAB is also reported.


Assuntos
Bacteriocinas , Lactobacillales , Lactococcus lactis , Nisina , Animais , Bacteriocinas/genética , Fermentação , Lactobacillales/genética , Lactobacillales/metabolismo , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Nisina/metabolismo
11.
FEMS Microbiol Lett ; 368(11)2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34086864

RESUMO

Artisanal products support the conservation of the indigenous biodiversity of food microbiomes, although they do not always comply to quality and hygienic requirements for the dairy industry. This study describes the development of an autochthonous starter culture to produce Matsoni, a traditional Georgian fermented milk. To this end, strains of lactic acid bacteria isolated from artisanal Matsoni samples were used to design a starter formulation reproducing the dominant microbial diversity, also preserving quality characteristics and ensuring the safety of the product. As a result, strains that represent the acidifying portion of the starter (Lactobacillus delbrueckii subsp. lactis, L. delbrueckii subsp. bulgaricus and Streptococcus thermophilus) were combined in different ratios and strain combinations, together with cultures of Lactobacillus rhamnosus that were chosen for their potential beneficial traits. The strain association acting better in milk cultures at laboratory scale was selected as starter culture for the production of Matsoni in pilot-scale industrial trials.


Assuntos
Produtos Fermentados do Leite/microbiologia , Produtos Fermentados do Leite/análise , Fermentação , Microbiologia de Alimentos , República da Geórgia , Concentração de Íons de Hidrogênio , Lactobacillales/classificação , Lactobacillales/crescimento & desenvolvimento , Lactobacillales/isolamento & purificação , Lactobacillales/metabolismo , Probióticos , Paladar
12.
Sci Rep ; 11(1): 12028, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103574

RESUMO

The lactic acid bacteria (LAB) Lactobacillus plantarum (strains 22F and 25F) and Pediococcus acidilactici (strain 72N) have appeared promising as replacements for antibiotics in in vitro studies. Microencapsulation, especially by the spray-drying method, has been used to preserve their numbers and characteristics during storage and digestion. This study compared the efficacy of these strains and their microencapsulated form with antibiotic usage on growth performance, faecal microbial counts, and intestinal morphology in nursing-finishing pigs. A total of 240 healthy neonatal pigs were treated on days 0, 3, 6, 9, and 12 after cross-fostering. Sterile peptone water was delivered orally to the control and antibiotic groups. Spray-dried Lactobacillus plantarum strain 22F stored for 6-months was administered to piglets in the spraydry group. Three ml of each the three fresh strains (109 CFU/mL) were orally administered to piglets in each group. All pigs received the basal diets, but these were supplemented with routine antibiotic for the antibiotic group. Pigs in all the probiotic supplemented groups exhibited a better average daily gain and feed conversion ratio than those of the controls in the nursery and grower phases. Probiotic supplementation increased viable lactobacilli and decreased enterobacterial counts. Antibiotic additives reduced both enterobacterial and lactobacilli counts. Villous height and villous height:crypt depth ratio were greater in probiotic and antibiotic supplemented pigs comparing to the controls, especially in the jejunum. The results demonstrated the feasibility of using these strains as a substitute for antibiotics and the practicality of the microencapsulation protocol for use in swine farms.


Assuntos
Antibacterianos/administração & dosagem , Fezes/microbiologia , Lactobacillales/metabolismo , Lactobacillus plantarum/metabolismo , Pediococcus acidilactici/metabolismo , Probióticos/administração & dosagem , Ração Animal/análise , Animais , Animais Recém-Nascidos , Peso Corporal , Dieta/veterinária , Suplementos Nutricionais , Esquema de Medicação , Feminino , Masculino , Suínos
13.
Folia Microbiol (Praha) ; 66(5): 761-774, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34110617

RESUMO

This study aimed to isolate lactic acid bacteria (LABs) of technological interest from Moroccan camel milk and select starter or adjunct culture for dairy product manufacturing. The phenotypic and biochemical identification of 47 isolates revealed the existence of ten Lactococcus lactis, eleven Lactobacillus plantarum, three Lactobacillus brevis, two Lactobacillus paracasei, eleven Enterococcus spp., seven Lactococcus spp. and two Lactobacillus spp. Our strains showed a fast acidifying ability (ΔpH ranged between 0.69 ± 0.01 and 1.22 ± 0.05 after 6 h), high proteolytic and autolytic activities (1.93 ± 0.02 to 9.9 ± 0.022 mM glycine and 15.21 ± 2.21% to 83.24 ± 1% respectively), and an important lipolytic and free radical scavenging capacity. Furthermore, they were able to use citrate, to produce exopolysaccharide, and they exhibited antibacterial activity against Gram-negative and Gram-positive pathogenic bacteria and had no hemolytic activity. This study has shown that Moroccan camel milk represents a rich biotope of interesting LABs for dairy products industry.


Assuntos
Microbiologia de Alimentos , Lactobacillales , Leite , Animais , Camelus , Laticínios/microbiologia , Lactobacillales/classificação , Lactobacillales/isolamento & purificação , Lactobacillales/metabolismo , Leite/microbiologia
14.
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
15.
Food Microbiol ; 99: 103836, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119120

RESUMO

Greece is a country possessing many cheese products granted with a PDO (Protected Designation of Origin) certificate, with high exporting activities. In this study, we analyzed six popular cheese PDO products purchased from different industries to assess their microbial communities using amplicon metabarcoding analysis. To this end, using Next Generation Sequencing technology, we sequenced the 16S rRNA gene and the ITS spacer for prokaryotes and fungi, respectively. Alpha diversity indices revealed higher bacterial species richness for some cheeses (Kopanisti, Batzos) and poor for others (Feta, Galotiri). Kopanisti, together with Kalathaki and Anevato, also presented increased species diversity concerning fungal populations. Results showed that lactic acid bacteria (LAB) prevailed the bacterial populations in all samples (Lactococcus, Lactobacillus, Streptococcus, Leuconostoc), whereas for fungi, members of the Saccharomycetaceae, Dipodascaceae and Debaryomycetaceae families prevailed the fungal populations. Several other genera were identified that make up each product's microbiome leading to the creation of the unique organoleptic attributes of Greek PDO cheeses. However, the identified species could not be directly linked to certain cheese types, assuming that starter and adjunct cultures, combined with the raw material used during production greatly impact the microbial communities in cheeses. Our data, produced for the first time for six Greek PDO cheeses, can be exploited in the process of creating a core microbial signature within each cheese type, supporting the Greek brand name and valorizing cheese products.


Assuntos
Queijo/microbiologia , Fungos/isolamento & purificação , Lactobacillales/isolamento & purificação , Microbiota , DNA Bacteriano/genética , Fungos/classificação , Fungos/genética , Fungos/metabolismo , Grécia , Lactobacillales/classificação , Lactobacillales/genética , Lactobacillales/metabolismo , Filogenia , RNA Ribossômico 16S/genética
16.
Int J Food Microbiol ; 350: 109242, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34044228

RESUMO

Lactic acid fermentation is a traditional process to preserve foods and to modify their organoleptic properties. This process is generally conducted in a spontaneous way, allowing indigenous lactic acid bacteria (LAB) of the matrix and of the environment to compete and grow. The aim of this study was to better characterise LAB strains ability to modify aroma profiles in fruit and vegetable matrices, by focusing on two key enzymatic activities: ß-glucosidase and alcohol dehydrogenase (ADH). Firstly, 200 LAB isolated from Cambodian and Vietnamese fermented foods were screened for their ß-glucosidase activity and duplicate isolates identified through RAPD-PCR analysis were discarded. Thereby, 40 strains were found positive for ß-glucosidase using p-nitrophenyl-ß-D-glucopyranoside as substrate. Among them, 14 displayed an activity greater than 10 nmol/min/mg dry cell. Thirteen were identified as Lactiplantibacillus (L.) plantarum and one as L. pentosus. Secondly, four strains of different phenotypes for ß-glucosidase activity were tested for ADH activity. The highest reduction ability for hexanal and (E)-2-hexenal was obtained for Limosilactobacillus (L.) fermentum V013-1A for which no ß-glucosidase activity was detectable. The three other strains (L. plantarum C022-2B, C022-3B, and V0023-4B2) exhibited a lower reduction ability and only for hexanal. Thirdly, mashed tomatoes were fermented with these four strains individually to evaluate their ability to release volatile compounds from the tomato precursors. Fifty-eight volatile compounds were identified and quantified by HS-SPME/GC-MS. Untreated tomatoes were rich in aldehydes. The tomatoes fermented with L. plantarum strains were rich in ketones whereas those with L. fermentum were rich in alcohols. However, for the generation of terpenoids that provide flower and fruit flavours, our screening of ß-glucosidase activity was not able to explain the differences among the strains. For ADH activity, L. fermentum exhibited a high activity in fermentation as most of the target aldehydes and ketones disappeared and were replaced by their corresponding alcohols. The L. plantarum strains exhibited a lower activity but with an important substrate-selectivity diversity. A better knowledge of the functionality of each LAB strain in the food matrix will permit to predict and shape the aroma profiles of fermented food.


Assuntos
Álcool Desidrogenase/metabolismo , Frutas/microbiologia , Lactobacillales/metabolismo , Verduras/microbiologia , beta-Glucosidase/metabolismo , Reatores Biológicos/microbiologia , Fermentação , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Ácido Láctico/análise , Lactobacillales/isolamento & purificação , Odorantes/análise , Técnica de Amplificação ao Acaso de DNA Polimórfico
17.
Microb Cell Fact ; 20(1): 109, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34049541

RESUMO

BACKGROUND: Plant-based milk alternatives are more popular than ever, and chickpea-based milks are among the most commercially relevant products. Unfortunately, limited nutritional value because of low levels of the essential amino acid L-lysine, low digestibility and unpleasant taste are challenges that must be addressed to improve product quality and meet consumer expectations. RESULTS: Using in-silico screening and food safety classifications, 31 strains were selected as potential L-lysine producers from approximately 2,500 potential candidates. Beneficially, 30% of the isolates significantly accumulated amino acids (up to 1.4 mM) during chickpea milk fermentation, increasing the natural level by up to 43%. The best-performing strains, B. amyloliquefaciens NCC 156 and L. paracasei subsp. paracasei NCC 2511, were tested further. De novo lysine biosynthesis was demonstrated in both strains by 13C metabolic pathway analysis. Spiking small amounts of citrate into the fermentation significantly activated L-lysine biosynthesis in NCC 156 and stimulated growth. Both microbes revealed additional benefits in eliminating indigestible sugars such as stachyose and raffinose and converting off-flavour aldehydes into the corresponding alcohols and acids with fruity and sweet notes. CONCLUSIONS: B. amyloliquefaciens NCC 156 and L. paracasei subsp. paracasei NCC 2511 emerged as multi-benefit microbes for chickpea milk fermentation with strong potential for industrial processing of the plant material. Given the high number of L-lysine-producing isolates identified in silico, this concept appears promising to support strain selection for food fermentation.


Assuntos
Vias Biossintéticas , Aromatizantes/metabolismo , Lactobacillales/genética , Lactobacillales/metabolismo , Lisina/biossíntese , Substitutos do Leite/metabolismo , Açúcares/metabolismo , Cicer/metabolismo , Fermentação , Microbiologia de Alimentos , Genoma Bacteriano , Lactobacillales/isolamento & purificação , Paladar
18.
Electron. j. biotechnol ; 51: 67-78, May. 2021. graf, tab
Artigo em Inglês | LILACS | ID: biblio-1343435

RESUMO

BACKGROUND: Endometritis is the most common disease of dairy cows and traditionally treated with antibiotics. Lactic acid bacteria can inhibit the growth of pathogens and also have potential for treatment of endometritis. Using PacBio single-molecule real-time sequencing technology, we sequenced the fulllength l6S rRNA of the microbiota in uterine mucus samples from 31 cows with endometritis, treated with lactic acid bacteria (experimental [E] group) and antibiotics (control [C] group) separately. Microbiota profiles taken before and after treatment were compared. RESULTS: After both treatments, bacterial species richness was significantly higher than before, but there was no significant difference in bacterial diversity. Abundance of some bacteria increased after both lactic acid bacteria and antibiotic treatment: Lactobacillus helveticus, Lactococcus lactis, Lactococcus raffinolactis, Pseudomonas alcaligenes and Pseudomonas veronii. The bacterial species that significantly decreased in abundance varied depending on whether the cows had been treated with lactic acid bacteria or antibiotics. Abundance of Staphylococcus equorum and Treponema brennaborense increased after lactic acid bacteria treatment but decreased after antibiotic treatment. According to COG-based functional metagenomic predictions, 384 functional proteins were significantly differently expressed after treatment. E and C group protein expression pathways were significantly higher than before treatment (p < 0.05). CONCLUSIONS: In this study, we found that lactic acid bacteria could cure endometritis and restore a normal physiological state, while avoiding the disadvantages of antibiotic treatment, such as the reductions in abundance of beneficial microbiota. This suggests that lactic acid bacteria treatment has potential as an alternative to antibiotics in the treatment of endometritis in cattle.


Assuntos
Animais , Feminino , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Endometrite/tratamento farmacológico , Lactobacillales/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Antibacterianos/administração & dosagem , Bactérias/isolamento & purificação , Bactérias/crescimento & desenvolvimento , Bactérias/efeitos dos fármacos , Útero/microbiologia , RNA Ribossômico 16S/genética , Ácido Láctico , Lactobacillales/genética , Microbiota
19.
Benef Microbes ; 12(2): 187-197, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33789554

RESUMO

Asthma is an inflammatory lung disease that affects more women than men in adulthood. Clinical evidence shows that hormonal fluctuation during the menstrual cycle and menopause are related to increased asthma severity in women. Considering that life expectancy has increased and that most women now undergo menopause, strategies to prevent the worsening of asthma symptoms are particularly important. A recent study from our group showed that re-exposure of ovariectomised allergic mice to antigen (ovalbumin) leads to an exacerbation of lung inflammation that is similar to clinical conditions. However, little is known about the role of probiotics in the prevention of asthma exacerbations during the menstrual cycle or menopause. Thus, our objective was to evaluate the effects of supplementation with kefir, a popular fermented dairy beverage, as a preventive strategy for modulating allergic disease. The results show that the preventive kefir administration decreases the influx of inflammatory cells in the airways and exacerbates the production of mucus and the interleukin 13 cytokine. Additionally, kefir changes macrophage polarisation by decreasing the number of M2 macrophages, as shown by RT-PCR assay. Thus, kefir is a functional food that potentially prevents allergic airway inflammation exacerbations in ovariectomised mice.


Assuntos
Asma/prevenção & controle , Kefir/microbiologia , Probióticos/administração & dosagem , Animais , Asma/genética , Asma/imunologia , Feminino , Fermentação , Humanos , Interleucina-13/genética , Interleucina-13/imunologia , Kefir/análise , Lactobacillales/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/efeitos adversos , Ovalbumina/imunologia
20.
Cells ; 10(3)2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33809924

RESUMO

Numerous honeybee (Apis mellifera) products, such as honey, propolis, and bee venom, are used in traditional medicine to prevent illness and promote healing. Therefore, this insect has a huge impact on humans' way of life and the environment. While the population of A. mellifera is large, there is concern that widespread commercialization of beekeeping, combined with environmental pollution and the action of bee pathogens, has caused significant problems for the health of honeybee populations. One of the strategies to preserve the welfare of honeybees is to better understand and protect their natural microbiota. This paper provides a unique overview of the latest research on the features and functioning of A. mellifera. Honeybee microbiome analysis focuses on both the function and numerous factors affecting it. In addition, we present the characteristics of lactic acid bacteria (LAB) as an important part of the gut community and their special beneficial activities for honeybee health. The idea of probiotics for honeybees as a promising tool to improve their health is widely discussed. Knowledge of the natural gut microbiota provides an opportunity to create a broad strategy for honeybee vitality, including the development of modern probiotic preparations to use instead of conventional antibiotics, environmentally friendly biocides, and biological control agents.


Assuntos
Abelhas/microbiologia , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Mel , Lactobacillales/metabolismo , Animais , Criação de Abelhas , Abelhas/efeitos dos fármacos , Abelhas/metabolismo , Disbiose , Interações Hospedeiro-Patógeno , Humanos , Inseticidas/efeitos adversos , Controle Biológico de Vetores , Probióticos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...