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1.
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 , Alimentos e Bebidas Fermentados/microbiologia , Marcadores Genéticos/genética , Lactobacillus sakei/genética , RNA Ribossômico 16S/genética
2.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443614

RESUMO

Kombucha is a traditional beverage of sweetened black tea fermented with a symbiotic association of acetic acid bacteria and yeasts. In this study, kombucha fermented beverage (KFB) appeared to include nine chemical groups (alcohols, acids, lactones, condensed heterocyclic compounds, antibiotics, esters, aldehydes, fatty acids, and alkaloids) of many bioactive metabolites, as elucidated by gas chromatography-mass spectrometry (GC-MS) and IR spectra. The fermented metabolic components of KFB seem collectively to act in a synergistic action giving rise to the antimicrobial activity. Four types of kombucha preparations (fermented, neutralized, heat-treated and unfermented) were demonstrated with respect to their antimicrobial activity against some pathogenic bacterial and fungal strains using agar well diffusion assay. KFB exerted the strongest antimicrobial activities when compared with neutralized and heat-treated kombucha beverages (NKB and HKB). Staphylococcus aureus ATCC6538 (S. aureus) and Escherichia coli ATCC11229 (E. coli) were the organisms most susceptible to the antimicrobial activity of kombucha beverage preparations. Finally, the KFB preparation showed remarkable inhibitory activity against S. aureus and E. coli bacteria in a brain heart infusion broth and in some Egyptian fruit juices (apple, guava, strawberry, and tomato). These data reveal that kombucha is not only a prophylactic agent, but also appears to be promising as a safe alternative biopreservative, offering protection against pathogenic bacteria and fungi.


Assuntos
Anti-Infecciosos/análise , Anti-Infecciosos/farmacologia , Alimentos e Bebidas Fermentados/análise , Alimentos e Bebidas Fermentados/microbiologia , Concentração de Íons de Hidrogênio
3.
Molecules ; 26(15)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34361631

RESUMO

The cyclic lipopeptide produced from Bacillus pumilus strain HY1 was isolated from Korean soybean sauce cheonggukjang. The chemical structures of the surfactin isomers were analyzed using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and electrospray ionization tandem mass spectrometry (ESI-MS/MS). The five potential surfactin isoforms were detected with protonated masses of m/z 994.7, 1008.7, 1022.7, 1036.7, and 1050.7 and different structures in combination with Na+, K+, and Ca2+ ions. ESI-MS/MS analysis revealed that the isolated surfactin possessed the precise amino acid sequence LLVDLL and hydroxyl fatty acids with 12 to 16 carbons. The surfactin content during cheonggukjang fermentation increased from 0.3 to 51.2 mg/kg over 60 h of fermentation. The mixture of five surfactin isoforms of cheonggukjang inhibited the growth of two cancer cell lines. The growth of both MCF-7 and Caco-2 cells was strongly inhibited with 100 µg/µL of surfactin. This study is the first-time report of five surfactin isomers of Bacillus pumilus strain HY1 during Korean soybean sauce cheonggukjang fermentation, which has cytotoxic properties.


Assuntos
Bacillus pumilus/metabolismo , Proliferação de Células/efeitos dos fármacos , Alimentos e Bebidas Fermentados/microbiologia , Lipopeptídeos , Soja/microbiologia , Células CACO-2 , Humanos , Lipopeptídeos/química , Lipopeptídeos/isolamento & purificação , Lipopeptídeos/farmacologia , Células MCF-7
4.
Int J Food Microbiol ; 354: 109317, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34225032

RESUMO

The purpose of the present study was to control the fermentation time and nitrite content of suancai prepared with Lactobacillus plantarum. According to analyses of the consumption amount and rate of nutrients, growth-stimulating nutrients, essential nutrients and nutrients accelerating the fermentation process of suancai, Asp, Thr, Glu, Cys, Tyr, Mg2+, Mn2+ and inosine were selected as additions to suancai prepared with L. plantarum. The fermentation time and nitrite content of suancai supplemented with nutrients and prepared with L. plantarum were shortened by 2 days and 5 days and reduced by approximately 0.1-fold and 0.7-fold, respectively, compared with unsupplemented suancai prepared with L. plantarum at 25 °C and 10 °C. The fermentation time and nitrite content of suancai supplemented with nutrients and prepared with L. plantarum were shortened by 6 days and 15 days and reduced by approximately 0.17-fold and 0.8-fold, respectively, compared with suancai undergoing spontaneous fermentation at 25 °C and 10 °C. Furthermore, no significant differences were observed in sensory properties in suancai. The results of this study indicated that certain nutrients accelerated the growth of L. plantarum and reduced the fermentation time and nitrite content of suancai prepared with L. plantarum. These findings help to establish a foundation for the practical use of nutrients to control the fermentation of suancai.


Assuntos
Alimentos e Bebidas Fermentados , Lactobacillus plantarum , Nutrientes , Fermentação , Alimentos e Bebidas Fermentados/análise , Alimentos e Bebidas Fermentados/microbiologia , Lactobacillus plantarum/metabolismo , Nitritos/análise , Nutrientes/metabolismo
5.
Int J Food Microbiol ; 354: 109316, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34247020

RESUMO

Fermented soy sauces are used as food seasonings in Eastern countries and all over the world. Depending on their cultural origins, their production differs in parameters such as wheat addition, temperature, and salt concentration. The fermentation of lupine seeds presents an alternative to the use of soybeans; however, the microbiota and influencing factors are currently unknown. In this study, we analyse the microbiota of lupine Moromi (mash) fermentations for a period of six months and determine the influence of different salt concentrations on the microbiota dynamics and the volatile compound composition. Cultured microorganisms were identified by protein profiling using matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS), and 16S rRNA gene amplicon sequencing provided an overview of the microbiota including non-cultured bacteria. The volatile compounds were determined by gas chromatography-mass spectrometry (GC-MS). At all salt concentrations, we found that Tetragenococcus halophilus (up to 1.4 × 109 colony forming units (CFU)/mL on day 21) and Chromohalobacter japonicus (1.9 × 109 CFU/mL, day 28) were the dominating bacteria during Moromi fermentation. Debaryomyces hansenii (3.6 × 108 CFU/mL, day 42) and Candida guilliermondii (2.2 × 108 CFU/mL, day 2) were found to be the most prevalent yeast species. Interestingly, Zygosaccharomyces rouxii and other yeasts described as typical for soy Moromi were not found. With increasing salinity, we found lower diversity in the microbiota, the prevalence-gain of typical species was delayed, and ratios differed depending on their halo- or acid tolerance. GC-MS analysis revealed aroma-active compounds, such as pyrazines, acids, and some furanones, which were mostly different from the aroma compounds found in soy sauce. The absence of wheat may have caused a change in yeast microbiota, and the use of lupine seeds may have led to the differing aromatic composition. Salt reduction resulted in a more complex microbiome, higher cell counts, and did not show any spoiling organisms. With these findings, we show that seasoning sauce that uses lupine seeds as the sole substrate is a suitable gluten-free, soy-free and salt reduced alternative to common soy sauces with a unique flavour.


Assuntos
Alimentos e Bebidas Fermentados , Lupinus , Microbiota , Sementes , Chromohalobacter/metabolismo , Enterococcaceae/metabolismo , Alimentos e Bebidas Fermentados/microbiologia , Microbiologia de Alimentos , Lupinus/química , Microbiota/efeitos dos fármacos , Microbiota/genética , RNA Ribossômico 16S/genética , Saccharomycetales/metabolismo , Sementes/microbiologia , Cloreto de Sódio/farmacologia
6.
Int J Food Microbiol ; 354: 109322, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34247021

RESUMO

During spontaneous meat fermentation, diverse microbial communities develop over time. These communities consist mainly of lactic acid bacteria (LAB) and coagulase-negative staphylococci (CNS), of which the species composition is influenced by the fermentation temperature and the level of acidification. Recent development and application of amplicon-based high-throughput sequencing (HTS) methods have allowed to gain deeper insights into the microbial communities of fermented meats. The aim of the present study was to investigate the effect of different fermentation temperatures and acidification profiles on the CNS communities during spontaneous fermentation, using a previously developed amplicon-based HTS method targeting both the 16S rRNA and tuf genes. Spontaneous fermentations were performed with five different lots of meat to assess inter-lot variability. The process influence was investigated by fermenting the meat batters for seven days at different fermentation temperatures (23 °C, 30 °C, and 37 °C) and in the absence or presence of added glucose to simulate different acidification levels. Additionally, the results were compared with a starter culture-initiated fermentation process. The data revealed that the fermentation temperature was the most influential processing condition in shaping the microbial communities during spontaneous meat fermentation processes, whereas differences in pH were only responsible for minor shifts in the microbial profiles. Furthermore, the CNS communities showed a great level of variability, which depended on the initial microbial communities present and their competitiveness.


Assuntos
Fermentação , Alimentos e Bebidas Fermentados , Microbiologia de Alimentos , Sequenciamento de Nucleotídeos em Larga Escala , Produtos da Carne , Microbiota , Alimentos e Bebidas Fermentados/microbiologia , Produtos da Carne/microbiologia , Microbiota/genética , RNA Ribossômico 16S/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-34313582

RESUMO

Thirteen Gram-stain-positive bacterial strains were isolated from Chinese traditional pickle and the gut of honeybee (Apis mellifera). These strains were characterized using a polyphasic taxonomic approach. The data demonstrated that 12 of the 13 strains represented eight novel species belonging to the genera Apilactobacillus, Secundilactobacillus, Levilactobacillus and Lacticaseibacillus; strains HN36-1T, 887-11T, F79-211-2T, 866-3T, 6-5(1)T, 13B17T, 117-1T and ZW152T were designated as the type strains. Based upon the data of polyphasic characterization obtained in the present study, eight novel species, Apilactobacillus nanyangensis sp. nov., Secundilactobacillus hailunensis sp. nov., Secundilactobacillus yichangensis sp. nov., Levilactobacillus andaensis sp. nov., Levilactobacillus wangkuiensis sp. nov., Levilactobacillus lanxiensis sp. nov., Lacticaseibacillus mingshuiensis sp. nov. and Lacticaseibacillus suilingensis sp. nov., are proposed and the type strains are HN36-1T (=JCM 33867T=CCTCC AB 2019385T), 887-11T (=NCIMB 15201T=CCM 8950T=JCM 33864T=CCTCC AB 2018396T), F79-211-2T (=NCIMB 15254T=JCM 33866T=CCTCC AB 2019384T), 866-3T (=JCM 33863T=CCTCC AB 2019383T), 6-5(1)T (=NCIMB 15229T=CCM 8977T=JCM 33564T=CCTCC AB 2019168T), 13B17T (=NCIMB 15230T=CCM 8979T=JCM 33565T=CCTCC AB 2019167T), 117-1T (=NCIMB 15232T=CCM 8980T=JCM 33567T) and ZW152T (=JCM 34363T=CCTCC AB 2020299T=LMG 32143T=CCM 9110T), respectively.


Assuntos
Abelhas/microbiologia , Alimentos e Bebidas Fermentados/microbiologia , Lactobacillaceae/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Microbiologia de Alimentos , Genes Bacterianos , Lactobacillaceae/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
8.
Int J Food Microbiol ; 354: 109248, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34059319

RESUMO

This work was carried out to elaborate selenium (Se) bio-enriched fermented Mediterranean fruit juices. To this purpose, pomegranate and table red grape juices were added with sodium selenite (Na2SeO3) and fermented by Levilactobacillus brevis CRL 2051 and Fructobacillus tropaeoli CRL 2034 individually or combined. To better evaluate the effect of selenite addition and starter strain inoculums on the total bacterial community of the fruit juices, fermentation trials were performed with raw and pasteurized fruit juices. No statistical significant differences were observed for total mesophilic microorganisms (TMM) and rod-shaped lactic acid bacteria (LAB) levels among raw and pasteurized juices inoculated with the starter strains, while significant differences between those juices with and without selenite were registered. LAB cocci, Pseudomonadaceae and yeasts were detected only for the raw juice preparations. The dominance of L. brevis CRL 2051 and F. tropaeoli CRL 2034 was confirmed by randomly amplified polymorphic DNA (RAPD)-PCR analysis. After fermentation, pH dropped for all inoculated trials and control raw juices. The soluble solid content (SSC) levels of the raw juices were higher than the corresponding pasteurized trials. The thermal treatment affected consistently yellowness of grape juice trials and redness of pomegranate juices. No microbial Se accumulation was registered for pomegranate juices, while F. tropaeoli CRL 2034 accumulated the highest amount of Se (65.5 µg/L) in the grape juice. For this reason, only trials carried out with raw grape juices were investigated by metagenomics analysis by Illumina MiSeq technology. Non-inoculated grape juices were massively fermented by acetic acid bacteria while Fructobacillus and Lactobacillus (previous genus name of Levilactobacillus) represented the highest operational taxonomy units (OTUs) relative abundance % of the trials inoculated with the starter strains as confirmed by this technique.


Assuntos
Fermentação , Alimentos e Bebidas Fermentados , Microbiologia de Alimentos , Sucos de Frutas e Vegetais , Ácido Láctico , Selênio , Alimentos e Bebidas Fermentados/microbiologia , Sucos de Frutas e Vegetais/microbiologia , Ácido Láctico/metabolismo , Lactobacillaceae/genética , Lactobacillaceae/metabolismo , Leuconostocaceae/genética , Leuconostocaceae/metabolismo , Região do Mediterrâneo , Técnica de Amplificação ao Acaso de DNA Polimórfico , Selênio/metabolismo
9.
Food Microbiol ; 99: 103820, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119105

RESUMO

Sub-Saharan region is often characterized by food and nutrition insecurity especially "hidden hunger" which results from inadequate micronutrients in diets. African indigenous leafy vegetables (AILVs) can represent a valid food source of micronutrients, but they often go to waste resulting in post-harvest losses. In an attempt to prolong AILVs shelf-life while enhancing their nutritional quality, fermentation was studied from a microbiological and nutritional point of view. Pumpkin leaves (Cucurbita sp.) were spontaneously fermented using the submerged method with 3% NaCl and 3% sucrose. Controls were set up, consisting of leaves with no additions. During fermentation, samples of both treatments were taken at 0, 24, 48, 72 and 168 h to monitor pH and characterize the microbial population through culture-based and molecular-based analyses. Variations between fresh and treated leaves in B-group vitamins, carotenoids, polyphenols, and phytic acid were evaluated. Data revealed that the treatment with addition of NaCl and sucrose hindered the growth of undesired microorganisms; in controls, unwanted microorganisms dominated the bacterial community until 168 h, while in treated samples Lactobacillaceae predominated. Furthermore, the content in folate, ß-carotene and lutein increased in treated leaves compared to the fresh ones, while phytic acid diminished indicating an amelioration in the nutritional value of the final product. Thus, fermentation could help in preserving Cucurbita sp. leaves, avoiding contamination of spoilage microorganisms and enhancing the nutritional values.


Assuntos
Cucurbita/química , Alimentos e Bebidas Fermentados/análise , Folhas de Planta/química , Verduras/química , Carotenoides/análise , Carotenoides/metabolismo , Cucurbita/microbiologia , Fermentação , Alimentos e Bebidas Fermentados/microbiologia , Segurança Alimentar , Lactobacillaceae/metabolismo , Valor Nutritivo , Folhas de Planta/microbiologia , Verduras/microbiologia , Vitaminas/análise , Vitaminas/metabolismo
10.
Nutrients ; 13(5)2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34062976

RESUMO

Dysbiosis of the gut microbiota has been associated with different illnesses and emotional disorders such as stress. Traditional fermented foods that are rich in probiotics suggest modulation of dysbiosis, which protects against stress-induced disorders. The academic stress was evaluated in medical students using the SISCO Inventory of Academic Stress before and after ingestion of an aguamiel-based beverage fermented with Lactobacillus plantarum, Lactobacillus paracasei and Lactobacillus brevis (n = 27) and a control group (n = 18). In addition, microbial phyla in feces were quantified by qPCR. The results showed that the consumption of 100 mL of a beverage fermented with lactic acid bacteria (3 × 108 cfu/mL) for 8 weeks significantly reduced academic stress (p = 0.001), while the control group (placebo intervention) had no significant changes in the perception of academic stress (p = 0.607). Significant change (p = 0.001) was shown in the scores for environmental demands, and physical and psychological factors. Consumption of the fermented beverage significantly increased the phyla Firmicutes and Bacteroidetes but not Gammaproteobacteria. No significant changes were found in the control group, except for a slight increase in the phylum Firmicutes. The intake of this fermented beverage suggest a modulation of gut microbiota and possible reduction in stress-related symptoms in university students, without changing their lifestyle or diet.


Assuntos
Agave , Alimentos e Bebidas Fermentados/microbiologia , Probióticos/administração & dosagem , Estresse Psicológico/terapia , Estudantes de Medicina/psicologia , Adulto , Disbiose/microbiologia , Disbiose/psicologia , Fezes/microbiologia , Feminino , Fermentação , Microbioma Gastrointestinal , Humanos , Lactobacillales , Estudos Longitudinais , Masculino , México , Estudos Prospectivos , Método Simples-Cego , Estresse Psicológico/microbiologia , Adulto Jovem
11.
Arch Microbiol ; 203(7): 4693-4703, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34189594

RESUMO

Six different fermented vegetables were collected from Zhejiang Province, China, to explore the associated bacterial community using a high-throughput sequencing platform. A total of 24 phyla, 274 families and 569 genera were identified from 6 samples. Firmicutes and Proteobacteria were the main phyla in all of the samples. Brevibacterium was the major genus in Xiaoshan pickled radish. Lactobacillus-related genera and Vibrio were the major genera in fermented potherb mustard and its brine. Enterobacter and Cobetia were the major genera in fermented radish and its brine. Chromohalobacter was the major genus in the tuber mustard. These results indicated clear differences were there between the bacterial genera present in Xiaoshan pickled radish, fermented potherb mustard, fermented radish, and tuber mustard. This demonstrated the possible influences of raw materials and manufacturing processes. Furthermore, a large number of lactic acid bacteria were isolated and identified by culture-dependent and 16S rRNA gene sequence analysis, which accounted for more than 68% of all the isolates. In addition, whole-genome analysis of Levilactobacillus suantsaii, Latilactobacillus sakei subsp. sakei, and Weissella cibaria showed that they had large numbers of genes associated with carbohydrate metabolism. This may explain why these three bacterial strains can grow in fermented vegetable environments.


Assuntos
Alimentos e Bebidas Fermentados , Microbiologia de Alimentos , Lactobacillales , Microbiota , Verduras , China , Alimentos e Bebidas Fermentados/microbiologia , Genoma Bacteriano/genética , Genômica , Lactobacillales/genética , Microbiota/genética , RNA Ribossômico 16S/genética , Verduras/microbiologia
12.
Food Chem ; 361: 129997, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34029911

RESUMO

The contribution of free amino acids and thiamine to the production of potent meat aroma compounds in nitrite-reduced, dry-fermented sausages inoculated with a D. hansenii strain was the objective of this study. For this, three different sausage formulations were manufactured; a control and two formulations reduced by half in nitrate and nitrite and one of them inoculated with D. hansenii. Free amino acids, thiamine content and savoury volatile compounds were analysed. Eleven savoury volatile compounds were quantitated. Among them, the most potent compounds above their odour thresholds were 2-methyl-3-furanthiol, 2-acetyl-1-pyrroline, methional, dimethyl trisulfide and methyl-2-methyl-3-furyl disulfide. Their generation was affected by D. hansenii inoculation as shown by the decrease in methional and methyl 2-methyl-3-furyl disulfide content, and the increase of methionol. Nitrate and nitrite reduction did not significantly affect amino acid and thiamine contents.


Assuntos
Aminoácidos/análise , Debaryomyces , Alimentos e Bebidas Fermentados/análise , Produtos da Carne/análise , Odorantes/análise , Aldeídos/análise , Fermentação , Alimentos e Bebidas Fermentados/microbiologia , Produtos da Carne/microbiologia , Nitratos/metabolismo , Nitritos/metabolismo , Tiamina/análise , Fermento Seco
13.
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 , Alimentos e Bebidas Fermentados/microbiologia , Frutas/microbiologia , Lactobacillales/metabolismo , Verduras/microbiologia , beta-Glucosidase/metabolismo , Reatores Biológicos/microbiologia , Fermentação , Alimentos e Bebidas Fermentados/análise , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Ácido Láctico/análise , Lactobacillales/isolamento & purificação , Odorantes/análise , Técnica de Amplificação ao Acaso de DNA Polimórfico
14.
Food Chem ; 358: 129863, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33940298

RESUMO

Traditional high-salt fermented Suanyu is an ethnic fermented fish product in southwest China. Lactic acid bacteria (LAB) are the most appropriate strains because of their technological properties during ripening fermentation. The diversity of LAB in high-salt fermented Chinese Suanyu was examined through high-throughput sequencing (HTS), and the most suitable LAB strain was acquired through strain isolation and characterization, surimi simulation fermentation system, and principal component analysis (PCA). The processing adaptability of the strain was examined via Suanyu fermentation. Results showed that Lactobacillus, Tetragenococcus, and Weissella were the dominant bacteria in Suanyu, and their contributions were 53.99%, 35.60%, and 4.10%, respectively. The most suitable strain (Lactobacillus plantarum B7) rapidly produced acid, exhibited a strong antibacterial activity, showed salt tolerance, and had no amino acid decarboxylase activity. pH decreased to about 3.6. Eventually, the ability to tolerate 20% salt was observed, and the activity of amino acid decarboxylase was negative. Fermented Suanyu with B7 rapidly produced acid (11.7% d-1). The non-protein nitrogen (NPN) and total free amino acid (FAA) contents of fermented Suanyu were higher and its total volatile base nitrogen (TVB-N), thiobarbituric acid (TBARS), and biogenic amines (BAs) levels were lower than those of naturally fermented Suanyu. Therefore, B7 is a potential microbial starter for Suanyu industrial production.


Assuntos
Bactérias/metabolismo , Alimentos e Bebidas Fermentados/microbiologia , Produtos Pesqueiros/microbiologia , Aminoácidos/análise , Animais , Bactérias/genética , Aminas Biogênicas/análise , Fermentação , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/metabolismo , RNA Ribossômico 16S , Weissella/isolamento & purificação
15.
J Microbiol Biotechnol ; 31(5): 726-732, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-33820888

RESUMO

In this study, we evaluated the immune-enhancing activity of kimchi-derived Lactobacillus plantarum 200655 on immune suppression by cyclophosphamide (CP) in ICR mice. Animals were fed distilled water or 1×109 colony-forming unit/kg B.W. 200655 or Lactobacillus rhamnosus GG as a positive control for 14 days. An in vivo model of immunosuppression was induced using CP 150 and 100 mg/kg B.W. at 7 and 10 days, respectively. Body weight, spleen index, spleen weight, and gene expression were measured to estimate the immune-enhancing effects. The dead 200655 (D-200655) group showed an increased spleen weight compared to the sham control (SC) group. Similarly, the spleen index was significantly higher than that in the CP-treated group. The live 200655 (L-200655) group showed an increased mRNA expression of tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6 in splenocytes. Also, the iNOS and COX-2 mRNA expression was upregulated in the L-200655 group compared to the CP-only (SC) group. The phosphorylation of ERK and MAPK was also upmodulated in the L-200655 group. These results indicate that L. plantarum 200655 ameliorated CP-induced immune suppression, suggesting that L. plantarum 200655 may have the potential to enhance the immune system.


Assuntos
Alimentos e Bebidas Fermentados/microbiologia , Hospedeiro Imunocomprometido/efeitos dos fármacos , Lactobacillus plantarum , Probióticos/farmacologia , Alanina Transaminase/sangue , Animais , Ciclofosfamida/farmacologia , Citocinas/metabolismo , Modelos Animais de Doenças , Hospedeiro Imunocomprometido/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Lactobacillus plantarum/isolamento & purificação , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Probióticos/administração & dosagem , República da Coreia , Baço/efeitos dos fármacos , Baço/imunologia
16.
J Microbiol ; 59(5): 460-466, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33907972

RESUMO

To date, all species in the genus Salicibibacter have been isolated in Korean commercial kimchi. We aimed to describe the taxonomic characteristics of two strains, NKC5-3T and NKC21-4T, isolated from commercial kimchi collected from various regions in the Republic of Korea. Cells of these strains were rod-shaped, Gram-positive, aerobic, oxidase- and catalase-positive, non-motile, halophilic, and alkalitolerant. Both strains, unlike other species of the genus Salicibibacter, could not grow without NaCl. Strains NKC5-3T and NKC21-4T could tolerate up to 25.0% (w/v) NaCl (optimum 10%) and grow at pH 7.0-10.0 (optimum 8.5) and 8.0-9.0 (optimum 8.5), respectively; they showed 97.1% 16S rRNA gene sequence similarity to each other and were most closely related to S. kimchii NKC1-1T (97.0% and 96.8% similarity, respectively). The genome of strain NKC5-3T was nearly 4.6 Mb in size, with 4,456 protein-coding sequences (CDSs), whereas NKC21-4T genome was nearly 3.9 Mb in size, with 3,717 CDSs. OrthoANI values between the novel strains and S. kimchii NKC1-1T were far lower than the species demarcation threshold. NKC5-3T and NKC21-4T clustered together to form branches that were distinct from the other Salicibibacter species. The major fatty acids in these strains were anteiso-C15:0 and anteiso-C17:0, and the predominant menaquinone was menaquinone-7. The polar lipids of NKC5-3T included diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), and five unidentified phospholipids (PL), and those of NKC21-4T included DPG, PG, seven unidentified PLs, and an unidentified lipid. Both isolates had DPG, which is the first case in the genus Salicibibacter. The genomic G + C content of strains NKC5-3T and NKC21-4T was 44.7 and 44.9 mol%, respectively. Based on phenotypic, genomic, phylogenetic, and chemotaxonomic analyses, strains NKC5-3T (= KACC 22040T = DSM 111417T) and NKC21-4T (= KACC 22041T = DSM 111418T) represent two novel species of the genus Salicibibacter, for which the names Salicibibacter cibarius sp. nov. and Salicibibacter cibi sp. nov. are proposed.


Assuntos
Bacillaceae/classificação , Bacillaceae/isolamento & purificação , Alimentos e Bebidas Fermentados/microbiologia , Filogenia , Bacillaceae/genética , Bacillaceae/fisiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/análise , Genômica , Concentração de Íons de Hidrogênio , Fosfolipídeos/análise , RNA Ribossômico 16S/genética , República da Coreia , Cloreto de Sódio , Especificidade da Espécie
17.
Food Microbiol ; 98: 103573, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875193

RESUMO

Chinese Sichuan Paocai (CSP) is one of the world's best-known fermented vegetables with a large presence in the Chinese market. The dynamic microbial community is the main contributor to Paocai fermentation. However, little is known about the ecological distribution and functional importance of these community members. In this study, metatranscriptomics was used to comprehensively explore the active microbial community members and key transcripts with significant functions in the Paocai fermentation process. Enterobacter, Leuconostoc, and Lactobacillus dominated the three-fermentation stages (Pre-, Mid- and Lat-), respectively. Carbon metabolism was the most abundant pathway. GH (glycoside hydrolase) and GT (lycosyl transferase) were the two most highly expressed carbohydrate-active enzymes. The most highly differentially expressed genes were grouped in the biosynthesis of amino acids, followed by glycolysis. Meta-pathways in the Sichuan Paocai fermentation ecosystem were reconstructed, Lactobacillaceae and Enterobacteriaceae were the two most important metabolic contributors. In addition, the nrfA and nirB were two genes referred to distinct nitrite reductase enzymes and 9 specialized genes, such as eclo, ron and ent were expressed to produce autoinducer 2 (AI-2) kinase in response to population density. The present study revealed functional enzymes and meta-pathways of the active microbial communities, which provide a deeper understanding of their contribution to CSP products.


Assuntos
Brassica/microbiologia , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/metabolismo , Alimentos e Bebidas Fermentados/microbiologia , Lactobacillaceae/isolamento & purificação , Microbiota , Verduras/microbiologia , Brassica/metabolismo , China , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Fermentação , Microbiologia de Alimentos , Lactobacillaceae/classificação , Lactobacillaceae/genética , Lactobacillaceae/metabolismo , Metagenômica , Transcriptoma , Verduras/metabolismo
18.
Food Microbiol ; 98: 103767, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875203

RESUMO

The variable quality of cocoa produced by farmers is still a problem in the value chain, strongly depending on microbial activities. We analyzed the variability of cocoa microbiota from all twelve producing regions in Cote d'Ivoire, and described the geographical distribution of isolated microbiota, using a mapping. Microbial species were identified by ribosomal genes sequencing, strains were typed by RFLP and their techno-functional capacities were further investigated. Results showed a restricted diversity of lactic acid bacteria (LAB) and acetic acid bacteria (AAB) with respectively 10 and 5 strains. The dominant LAB and AAB strains, notably Lactobacillus plantarum 1 A, Acetobacter pasteurianus 1 A, Acetobacter okinawensis 2 A, and Acetobacter tropicalis 3 A, were found in all regions assuming that the acid microbiota was weakly variable. In contrast, the distribution of their functional performance such as acidification capability was variable, stronger in strains from Nawa and Haut-Sassandra regions and weaker in Indenie-Djuablin and San Pedro; this distribution seemed to be random. Moreover, the study also revealed a complex yeasts population showing a wide genetic diversity with 22 species and 45 strains indicating an intraspecific heterogeneity. Strains were generally different from a region to another and the resulting yeasts microbiota was globally variable in the regions. Likewise, the functional capacities such as pectinolytic was weak in P. kudriazevii strain 2 K from Gboklè and strong in P. kudriazevii strain 2 A from Loh-Djiboua. Additionally, the quality of fermented beans was also variable in the regions. The great variation of yeasts strains in the different regions may be the main microbial factors responsible for variation of the fermented cocoa quality observed.


Assuntos
Bactérias/isolamento & purificação , Bactérias/metabolismo , Cacau/microbiologia , Microbiota , Leveduras/isolamento & purificação , Leveduras/metabolismo , Ácido Acético/metabolismo , Bactérias/classificação , Bactérias/genética , Biodiversidade , Cacau/metabolismo , Costa do Marfim , Fermentação , Alimentos e Bebidas Fermentados/microbiologia , Ácido Láctico/metabolismo , Sementes/metabolismo , Sementes/microbiologia , Leveduras/classificação , Leveduras/genética
19.
Food Microbiol ; 98: 103787, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875215

RESUMO

The fungal communities and volatile compounds of traditional dry sausages collected from five different regions in Northeast China, including Harbin (HRB), Daqing (DQ), Suihua (SH), Hegang (HG) and Mudanjiang (MDJ) were investigated in this study. The results revealed clear differences among the fungal community structures of the sausages. Aspergillus pseudoglaucus, Debaryomyces hansenii, and Trichosporon asahii were found to be the predominant species in the sausages from HRB, HG, and MDJ, respectively. Candida zeylanoides was the predominant species in the sausage from DQ and SH. Additionally, 88 volatile compounds were identified in all sausages, of which 31 volatile compounds were the most important flavor contributors (odor activity value > 1). Potential correlation analysis revealed that 8 fungi (D. hansenii, C. zeylanoides, T. asahii, A. pseudoglaucus, Aspergillus sydowii, Penicillium expansum, A. alternata, and Alternaria tenuissima) showed significant positive correlations with ≥3 key volatile compounds. Among these fungi, D. hansenii was regarded as a core functional fungus responsible for the formation of the volatile compounds, given its strong connection with the highest number of key volatile compounds. These results provide detailed insight into the fungal communities of traditional dry sausages and a deeper understanding of the contribution of these fungi to sausage flavor.


Assuntos
Alimentos e Bebidas Fermentados/microbiologia , Fungos/isolamento & purificação , Fungos/metabolismo , Produtos da Carne/microbiologia , Micobioma , Compostos Orgânicos Voláteis/metabolismo , Animais , Fermentação , Alimentos e Bebidas Fermentados/análise , Microbiologia de Alimentos , Fungos/classificação , Fungos/genética , Odorantes/análise , Suínos , Paladar , Compostos Orgânicos Voláteis/análise
20.
Sci Data ; 8(1): 113, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879798

RESUMO

ODFM is a data management system that integrates comprehensive omics information for microorganisms associated with various fermented foods, additive ingredients, and seasonings (e.g. kimchi, Korean fermented vegetables, fermented seafood, solar salt, soybean paste, vinegar, beer, cheese, sake, and yogurt). The ODFM archives genome, metagenome, metataxonome, and (meta)transcriptome sequences of fermented food-associated bacteria, archaea, eukaryotic microorganisms, and viruses; 131 bacterial, 38 archaeal, and 28 eukaryotic genomes are now available to users. The ODFM provides both the Basic Local Alignment Search Tool search-based local alignment function as well as average nucleotide identity-based genetic relatedness measurement, enabling gene diversity and taxonomic analyses of an input query against the database. Genome sequences and annotation results of microorganisms are directly downloadable, and the microbial strains registered in the archive library will be available from our culture collection of fermented food-associated microorganisms. The ODFM is a comprehensive database that covers the genomes of an entire microbiome within a specific food ecosystem, providing basic information to evaluate microbial isolates as candidate fermentation starters for fermented food production.


Assuntos
Gerenciamento de Dados/métodos , Bases de Dados Genéticas , Alimentos e Bebidas Fermentados/microbiologia , Metagenoma , Archaea/genética , Bactérias/genética , Vírus/genética
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