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1.
J Agric Food Chem ; 68(6): 1741-1749, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31964137

RESUMO

The goal of this study was to explore the regulatory mechanisms of phenyllactic acid (PLA) overaccumulation in Lactobacillus plantarum. The dynamics of PLA production revealed that 24 h was a suitable fermentation time, at which one of the largest differences in PLA content between strains S1 and YM-4-3 was 22.42 mg/L. Additionally, an optimization experiment showed that PLA production under the optimal condition (sample YM-4-3y) was up to 400.74 mg/L, 7.61-13.26 times as those of YM-4-3 and S1. Subsequently, an integrated analysis of genomic, transcriptomic and metabolomic data revealed that, YM-4-3 and YM-4-3y, compared with S1, although lacking a complete de novo biosynthetic pathway, increased PLA production by strengthening the core pathway and central carbon metabolism, and weakening the biosynthesis pathway of amino acids and their derivatives. These changes can provide sufficient precursors and compensate for or balance the energy consumed by the reinforced core pathway.


Assuntos
Lactatos/metabolismo , Lactobacillus plantarum/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Vias Biossintéticas , Fermentação , Genômica , Cinética , Lactatos/química , Lactobacillus plantarum/química , Lactobacillus plantarum/genética
2.
Food Microbiol ; 87: 103389, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948630

RESUMO

To overcome the deleterious effects of hydrogen peroxide, Lactobacillus plantarum elicits an adaptive response to oxidative stress. In this study, global transcriptomic analysis revealed that L. plantarum CAUH2 expanded its carbon source utilizing profile and enhanced glycolysis to produce more ATP to confront with H2O2 stress. Some antioxidant enzymes including NADH peroxidase, thioredoxin reductase and glutathione peroxidase were 6.11, 36.76 and 6.23-fold up-regulated at transcription level for H2O2 scavenging. Meanwhile, free ferrous iron (Fe2+) was maintained at low concentrations in the cytoplasm, which could limit Fenton reaction and reduce the production of hydroxyl radicals. To repair DNA lesion caused by H2O2, both base excision repair system and recombinational DNA repair pathway were employed by L. plantarum CAUH2. In addition, the expression of methionine sulfoxide reductases and thioredoxin were up-regulated to repair oxidized proteins. It is noteworthy that some transcriptional regulators (Spx, CcpA and MarR1) were predicted to participate in the adaptive response to H2O2 stress, suggesting that L. plantarum CAUH2 utilized a wide array of sensors to monitor oxidative stress and modulated the transcriptional regulation network under H2O2 stress. These findings provide novel insight into the protective mechanisms developed by L. plantarum to cope with oxidative stress.


Assuntos
Proteínas de Bactérias/genética , Peróxido de Hidrogênio/farmacologia , Lactobacillus plantarum/efeitos dos fármacos , Lactobacillus plantarum/genética , Proteínas de Bactérias/metabolismo , Perfilação da Expressão Gênica , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Lactobacillus plantarum/enzimologia , Lactobacillus plantarum/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidases/genética , Peroxidases/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Transcriptoma/efeitos dos fármacos
3.
J Sci Food Agric ; 100(5): 2007-2017, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31849068

RESUMO

BACKGROUND: Previous studies have shown that Lactobacillus plantarum LIP-1 (hereafter LIP-1) has an obvious hypolipidemic effect, and microencapsulated probiotics can ensure the strains live through the gastrointestinal tract. Although there has been much research on both preparation and assessment methods for probiotics microcapsules, most assessments were made in vitro and few were validated in vivo. In this study, the protective effect of microencapsulation and the possible hypolipidemic mechanisms of probiotic LIP-1 were evaluated in rats. Treatments included rats fed on a normal diet, a high-fat diet, and a high-fat diet with an intragastric supplement of either non-microencapsulated LIP-1 cells (NME LIP-1) or microencapsulated LIP-1 (ME LIP-1). Lipid metabolism indicators were measured during the experiment and following euthanasia. RESULTS: Microencapsulation increased survival and colonization of LIP-1 in the colon. ME LIP-1 was superior to NME LIP-1 in reducing cholesterol. The mechanisms behind the hypolipidemic effect exerted by LIP-1 are possibly due to promoting the excretion of cholesterol, improving antioxygenic potentials, enhancing recovery from the injury in the liver, cardiovascular intima and intestinal mucosa, promoting the generation of short-chain fatty acids, and improving lipid metabolism. CONCLUSIONS: This study confirms that microencapsulation provides effective protection of LIP-1 in the digestive system and the role of LIP-1 in the prevention and cure of hyperlipidaemia, providing theoretical support for probiotics to enter clinical applications. © 2019 Society of Chemical Industry.


Assuntos
Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/administração & dosagem , Lactobacillus plantarum/metabolismo , Probióticos/administração & dosagem , Animais , Cápsulas/administração & dosagem , Dieta Hiperlipídica/efeitos adversos , Humanos , Hiperlipidemias/metabolismo , Lactobacillus plantarum/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar
4.
Food Microbiol ; 86: 103336, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31703861

RESUMO

Plant derived galactomannooligosaccharides (GMOS) are an emerging class of prebiotics, but no information is available on their utilization in lactobacilli at the molecular level. The current study aimed at identifying the genetic loci involved in the transport and catabolism of locust bean gum derived GMOS in Lactobacillus plantarum WCFS1. Substrate depletion study showed that L. plantarum WCFS1 can metabolize only short chain GMOS (degree of polymerization; DP ≤ 3). Global transcriptome microarray profiling of L. plantarum WCFS1 revealed differential expression when GMOS or control sugars (glucose, galactose, and mannose) were used as a sole carbohydrate source. Two genetic loci involved in cellobiose (~3.2 kb) and oligo-sucrose (~7.3 kb) utilization in L. plantarum WCFS1 were highly up-regulated up to 8.3 and up to 6.7-fold, respectively by GMOS utilization. qRT-PCR studies of the selected gene clusters showed correlation with microarray data. Altogether, transcriptome and qRT-PCR studies of L. plantarum WCFS1 suggested that un-substituted mannobiose (DP2) might be metabolized by proteins encoded by the cellobiose operon while, substituted DP2 (galactomannose) and DP3 (galactomannobiose) were most likely transported and catabolized by the oligo-sucrose utilization loci encoded proteins.


Assuntos
Proteínas de Bactérias/genética , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Oligossacarídeos/metabolismo , Proteínas de Bactérias/metabolismo , Galactose/metabolismo , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Glucose/metabolismo , Manose/metabolismo , Família Multigênica , Oligossacarídeos/química , Óperon
5.
Meat Sci ; 159: 107917, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31494521

RESUMO

In this study, effects of ingoing nitrite level (0, 50, 100 and 150 mg/kg), use of sodium ascorbate, addition of starter culture (Lactobacillus plantarum GM77 + Staphylococcus xylosus GM92) and cooking level (control, medium, medium well, well done and very well done) on nitrosamine formation in heat-treated sucuk, a type of semi-dry fermented sausage, were investigated. The use of ascorbate had no significant effect on NDMA (N-Nitrosodimethylamine) and NPIP (N-Nitrosopiperidine) contents in the presence of starter culture. A higher NPYR (N- Nitrosopyrrolidine) content was detected in the group with starter culture at 150 mg/kg nitrite level in comparison to the group without starter culture. Cooking level affected all identified nitrosamines very significantly. Ingoing nitrite level × cooking level interaction was only effective on NPIP and advanced cooking levels (well done and very well done) at higher ingoing nitrite levels (100 and 150 mg/kg) resulted in significant increases in NPIP content.


Assuntos
Ácido Ascórbico/química , Culinária , Dimetilnitrosamina/química , Produtos da Carne/análise , Nitritos/química , Animais , Bacteriocinas , Bovinos , Microbiologia de Alimentos , Temperatura Alta , Fosfatos de Inositol , Lactobacillus plantarum/metabolismo , Produtos da Carne/microbiologia , Carne Vermelha , Staphylococcus/metabolismo
6.
Food Chem ; 307: 125529, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31644982

RESUMO

Ten lactic acid bacteria (LAB) strains of different species isolated from Chinese traditional sourdough were investigated on their volatile compounds in sourdough fermentation. Sourdoughs fermented with different LAB species were analyzed by principal component analysis (PCA) based on their volatiles. Furthermore, the in situ gene expressions of Lactobacillus sanfranciscensis during sourdough fermentation were investigated by using RNA sequencing for the first time. PCA could discriminate between the sourdoughs fermented by homofermentative and heterofermentative LAB, the former containing more aldehydes and ketones with more than 6 carbon atoms, while the latter featuring ethanol and esters. The Lactobacillus plantarum-fermented sourdough was characterized by high C4-C6 volatiles content, while L. sanfranciscensis showed a unique volatile profile without explicit explanatory compounds. The RNA sequencing suggested that, compared to the sourdough fermented for 6 h, L. sanfranciscensis enhanced carbohydrate metabolism and self-protection activities, but decreased cell proliferation in sourdough at 12 h.


Assuntos
Pão/análise , Fermentação , Aromatizantes/metabolismo , Lactobacillus/metabolismo , Transcriptoma , /análise , Aromatizantes/análise , Microbiologia de Alimentos , Lactobacillus/genética , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Análise de Sequência de RNA , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
7.
Food Microbiol ; 86: 103330, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31703878

RESUMO

Pickle is a type of mildly lactic acid fermented vegetable and is a traditional dish favored in China, Japan, and Korea. Corruption of spoilage bacteria and accumulation of nitrite during vegetable fermentation are common problems that affect the pickle industry and consumer health. In this work, cucumber juice was used as a vegetable model to study the dominant mesophilic aerobic bacteria (MAB) producing nitrite during pickle fermentation. Virulent phages infecting the dominant MABs combined with Lactobacillus plantarum M6 were used to control these bacteria. Enterobacter cloacae and Pseudomonas fluorescens are the dominant MABs in the fermentation of cucumber juice containing 4% or 8% NaCl, with isolation percentages reaching 30.6% and 23.1%, respectively. Virulent phages PspYZU5415 and EcpYZU01 were isolated using P. fluorescens J5415 and E. cloacae J01 as the host bacteria, respectively. These two phages show a broad host range and strong lytic activity, and their genomes contain no toxins and antibiotic resistance genes. PspYZU5415 and EcpYZU01 were combined into a cocktail (designated as Phage MIX) that effectively inhibits the growth of E. cloacae and P. fluorescens in cucumber juice with different salt concentrations. PhageMIX combined with L. plantarum M6 decreased the counts of P. mendocina and E. cloacae to undetectable levels at 48 h during the fermentation of cucumber juice artificially contaminated with P. mendocina and E. cloacae. In addition, nitrite content increased to 11.3 mg/L at 20 h and then degraded completely at 36 h. By contrast, P. mendocina and E. cloacae remained in the groups without PhageMIX during fermentation (0-48 h). Nitrite content rapidly increased to 65.7 mg/L at 12 h and then decreased to 21.6 mg/L at 48 h in the control group. This study suggests that PhageMIX combined with lactic acid bacterial strains can be used as an ecological starter for controlling the dominant MABs P. mendocina and E. cloacae and for reducing nitrate production during the early stage of pickle fermentation.


Assuntos
Bacteriófagos/fisiologia , Bacteriófagos/patogenicidade , Cucumis sativus/microbiologia , Enterobacter cloacae/virologia , Microbiologia de Alimentos/métodos , Pseudomonas fluorescens/virologia , Verduras/microbiologia , Aerobiose , Bacteriófagos/genética , Bacteriófagos/isolamento & purificação , Cucumis sativus/metabolismo , Enterobacter cloacae/metabolismo , Fermentação , Especificidade de Hospedeiro , Lactobacillus plantarum/metabolismo , Nitritos/metabolismo , Pseudomonas fluorescens/metabolismo
8.
J Appl Microbiol ; 128(1): 191-201, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31561280

RESUMO

AIMS: To investigate the genetic determinates for conjugated linolenic acid (CLNA) production in Lactobacillus plantarum ZS2058, a high CLNA producer. METHODS AND RESULTS: After culturing with α-linolenic acid (ALA) in the medium, the fatty acid compositions of supernatant fluid and cell pellets were analysed via GC-MS. cis9,trans11,cis15-CLNA was identified to be the predominant isomer. And during CLNA production, 10-hydroxy-cis12-cis15-octadecenoic acid (10-HOEA) and 10-oxo-cis12-cis15-octadecenoic acid (10-OXOA) were accumulated. The E. coli recombinants harbouring genes encoding myosin-cross-reactive antigen (MCRA), short-chain dehydrogenase/oxidoreductase (DH) and acetoacetate decarboxylase (DC), respectively, were analysed for their roles in CLNA production. The results indicated that MCRA converted ALA to 10-HOEA, following converted to 10-OXOA by DH. While with the combination of three recombinants, ALA could be transformed into CLNA plus 10-HOEA and 10-OXOA. When the three genes were deleted, none of the L. plantarum ZS2058 knockout mutants could produce any CLNA, after complementation, and all the complementary mutants recovered the CLNA-production ability at similar levels as the wild strain. CONCLUSIONS: Lactobacillus plantarum ZS2058 produced CLNA from ALA with 10-HOEA and 10-OXOA as intermediates. The triple-component isomerase of MCRA, DH and DC was the unique genetic determinant for CLNA generation. SIGNIFICANCE AND IMPACT OF THE STUDY: The current results firstly provided conclusive evidence that the triple-component isomerase complex was shared by both CLA and CLNA production in lactobacilli.


Assuntos
Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Ácidos Linoleicos Conjugados/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Escherichia coli/genética , Ácidos Graxos/análise , Isomerases/genética , Isomerases/metabolismo , Ácidos Linoleicos Conjugados/química , Complexos Multienzimáticos , Ácidos Oleicos/química , Ácidos Oleicos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ácido alfa-Linoleico/metabolismo
9.
Meat Sci ; 160: 107958, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31669862

RESUMO

This study focused on sarcoplasmic and myofibrillar protein degradation and the formation of peptides with antioxidant activity by mixed starters (Lactobacillus plantarum CD101 and Staphylococcus simulans NJ201). Gel electrophoresis indicated that the mixed starters can hydrolyze both sarcoplasmic and myofibrillar proteins, and the concentration of peptides increased (P < .05). Compared with the control group, using mixed starters led to a significant increase (P < .05) in the DPPH radical scavenging activity, Fe2+ chelating activity, and ABTS radical scavenging activity of sarcoplasmic proteins, but demonstrated no significant difference in myofibrillar proteins. Two hydrophobic fractions (C2, C5) separated by RP-HPLC in the inoculation groups with sarcoplasmic proteins showed high DPPH radical scavenging activity (66.60%, 60.50%). Eighteen peptides were identified by LC-MS/MS, which mainly arose from triosephosphate isomerase, creatine kinase M-type, and glyceraldehyde-3-phosphate dehydrogenase. Hydrophobic amino acids accounted for a large proportion. Our results indicate that mixed starters affect proteolytic characterization and contribute to the formation of peptides with antioxidant capacity in sarcoplasmic proteins.


Assuntos
Lactobacillus plantarum/metabolismo , Produtos da Carne/microbiologia , Proteólise , Staphylococcus/metabolismo , Animais , Antioxidantes/química , Fermentação , Proteínas Musculares/metabolismo , Miofibrilas/metabolismo , Peptídeos/metabolismo , Suínos
10.
J Microbiol Biotechnol ; 29(11): 1729-1738, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31635439

RESUMO

In sourdough fermentation, lactic acid bacteria perform important roles in the production of volatile and antimicrobial compounds, and exerting health-promoting effects. In this study, we report the probiotic properties and baking characteristics of Lactobacillus plantarum SPC-SNU 72-2 isolated from kimchi. This strain is safe to use in food fermentation as it does not carry genes for biogenic amine production (i.e., hdc, tdc, and ldc) and shows no ß-hemolytic activity against red blood cells. The strain is also stable under simulated human gastrointestinal conditions, showing tolerance to gastric acid and bile salt, and adheres well to colonic epithelial cells. Additionally, this strain prevents pathogen growth and activates mouse peritoneal macrophages by inducing cytokines such as tumor necrosis factor-α, interleukin (IL)-6, and IL-12. Furthermore, the strain possesses good baking properties, providing rich aroma during dough fermentation and contributing to the enhancement of bread texture. Taken together, L. plantarum SPC-SNU 72-2 has the properties of a good starter strain based on the observation that it improves bread flavor and texture while also providing probiotic effects comparable with commercial strains.


Assuntos
Pão/microbiologia , Microbiologia de Alimentos , Lactobacillus plantarum/metabolismo , Probióticos/metabolismo , Animais , Antibiose , Aderência Bacteriana , Ácidos e Sais Biliares/metabolismo , Pão/análise , Células CACO-2 , Fermentação , Humanos , Imunomodulação , Lactobacillus plantarum/genética , Lactobacillus plantarum/fisiologia , Maltose/metabolismo , Camundongos , Viabilidade Microbiana , Probióticos/análise , Compostos Orgânicos Voláteis/análise
11.
Microb Cell Fact ; 18(1): 183, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655584

RESUMO

BACKGROUND: α-Amylases specifically catalyse the hydrolysis of the internal α-1, 4-glucosidic linkages of starch. Glycoside hydrolase (GH) family 13 is the main α-amylase family in the carbohydrate-active database. Lactobacillus plantarum WCFS1 possesses eleven proteins included in GH13 family. Among these, proteins annotated as maltose-forming α-amylase (Lp_0179) and maltogenic α-amylase (Lp_2757) were included. RESULTS: In this study, Lp_0179 and Lp_2757 L. plantarum α-amylases were structurally and biochemically characterized. Lp_2757 displayed structural features typical of GH13_20 subfamily which were absent in Lp_0179. Genes encoding Lp_0179 (Amy2) and Lp_2757 were cloned and overexpressed in Escherichia coli BL21(DE3). Purified proteins showed high hydrolytic activity on pNP-α-D-maltopyranoside, being the catalytic efficiency of Lp_0179 remarkably higher. In relation to the hydrolysis of starch-related carbohydrates, Lp_0179 only hydrolysed maltopentaose and dextrin, demonstrating that is an exotype glucan hydrolase. However, Lp_2757 was also able to hydrolyze cyclodextrins and other non-cyclic oligo- and polysaccharides, revealing a great preference towards α-1,4-linkages typical of maltogenic amylases. CONCLUSIONS: The substrate range as well as the biochemical properties exhibited by Lp_2757 maltogenic α-amylase suggest that this enzyme could be a very promising enzyme for the hydrolysis of α-1,4 glycosidic linkages present in a broad number of starch-carbohydrates, as well as for the investigation of an hypothetical transglucosylation activity under appropriate reaction conditions.


Assuntos
Proteínas de Bactérias/química , Glicosídeo Hidrolases/química , Lactobacillus plantarum/metabolismo , alfa-Amilases/química , Clonagem Molecular , Escherichia coli/genética , Polissacarídeos/metabolismo , Amido/metabolismo , Especificidade por Substrato
12.
Nat Commun ; 10(1): 4548, 2019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591402

RESUMO

There are many industrially-relevant enzymes that while active, are severely limited by thermodynamic, kinetic, or stability issues (isomerases, lyases, transglycosidases). In this work, we study Lactobacillus sakei L-arabinose isomerase (LsLAI) for D-galactose to D-tagatose isomerization-that is limited by all three reaction parameters. The enzyme demonstrates low catalytic efficiency, low thermostability at temperatures > 40 °C, and equilibrium conversion < 50%. After exploring several strategies to overcome these limitations, we show that encapsulating LsLAI in gram-positive Lactobacillus plantarum that is chemically permeabilized enables reactions at high rates, high conversions, and elevated temperatures. In a batch process, this system enables ~ 50% conversion in 4 h starting with 300 mM galactose (an average productivity of 37 mM h-1), and 85% conversion in 48 h. We suggest that such an approach may be invaluable for other enzymatic processes that are similarly kinetically-, thermodynamically-, and/or stability-limited.


Assuntos
Aldose-Cetose Isomerases/metabolismo , Proteínas de Bactérias/metabolismo , Galactose/metabolismo , Hexoses/metabolismo , Lactobacillus plantarum/enzimologia , Aldose-Cetose Isomerases/genética , Proteínas de Bactérias/genética , Biocatálise , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Isomerismo , Cinética , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Temperatura Ambiente
13.
Molecules ; 24(20)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618866

RESUMO

Proteolysis in fermented milk, a complex and dynamic process, depends on the starter cultures used. This study aimed to evaluate the influence of Lactobacillus plantarum or Bifidobacterium animalis subsp. lactis, or both, co-fermented with Streptococcus thermophilus, on the changes in the proteolysis profile of fermented milk during 21-day storage at 4 °C, including the pH value, proteolytic degree, protease activity, aminopeptidase activity, free amino acid content, and electrophoresis performance. The results showed that the treatments with co-cultures exhibited a higher amount of free amino groups and neutral protease activity at an extracellular level, whereas lower pH values and aminopeptidase activities towards the six substrates at an intracellular level than the ones with a single-strain of S. thermophilus over the refrigerated storage were observed. In co-fermentation with S. thermophilus, B. animalis subsp. lactis did not significantly affect the concentrations of most free amino acids, while contributions of L. plantarum were found. Electrophoresis indicated that the mixed starters, especially the co-cultures containing L. plantarum, showed a stronger degradation for caseins than the pure S. thermophilus culture. These findings suggest that culture combinations may influence the proteolysis characteristics of the fermented products, and probiotic cultures must be carefully chosen for fermented production.


Assuntos
Bifidobacterium animalis , Produtos Fermentados do Leite/análise , Armazenamento de Alimentos , Lactobacillus plantarum , Streptococcus thermophilus , Aminoácidos , Bifidobacterium animalis/metabolismo , Fermentação , Microbiologia de Alimentos , Lactobacillus plantarum/metabolismo , Peptídeo Hidrolases , Proteólise , Streptococcus thermophilus/metabolismo
14.
J Basic Microbiol ; 59(11): 1134-1142, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31549433

RESUMO

Oenococcus oeni is the main bacteria extensively used in malolactic fermentation due to its high tolerance against stress factors in wine production. Among these, ethanol is one of the main challenges to O. oeni, and its ethanol tolerance mechanism remains unclear. In this study, the puuE gene related to ethanol tolerance from O. oeni SD-2a was heterologously expressed in Lactobacillus plantarum WCFS1. Results showed that the recombinant strain (W-pMG36epuuE) exhibited better growth performance and survival rate compared to the control strain (W-pMG36e) under ethanol-stress conditions. In addition, it was found that the activities of superoxide dismutase and the concentration of glutathione of W-pMG36epuuE were significantly higher than those of W-pMG36e. This resulted in the decrease of intracellular reactive oxygen species (ROS) accumulation (10.34% lower than control). Moreover, heterologous expression of puuE in WCFS1 exhibited improved activities of two ATPases in membrane, increasing the cell membrane integrity (37.67% higher than control). These results revealed the role of the puuE gene in improving ethanol tolerance in O. oeni by decreasing ROS accumulation and enhancing cell membrane integrity.


Assuntos
4-Aminobutirato Transaminase/genética , Proteínas de Bactérias/genética , Etanol/metabolismo , Lactobacillus plantarum/metabolismo , Oenococcus/enzimologia , 4-Aminobutirato Transaminase/metabolismo , Proteínas de Bactérias/metabolismo , Membrana Celular/metabolismo , Fermentação , Lactobacillus plantarum/genética , Lactobacillus plantarum/crescimento & desenvolvimento , Oenococcus/genética , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Vinho/microbiologia
15.
J Dairy Sci ; 102(12): 10838-10844, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31548063

RESUMO

Lactobacillus plantarum J26, a significant probiotic isolated from Chinese traditional fermented dairy products, exerts a positive immunomodulatory effect by regulating the expression of immune-related genes. We investigated expression of the cytokines IL-1α, IL-1ß, IL-6, and tumor necrosis factor-α in the intestinal tract of mice stimulated by L. plantarum J26. In vivo, these cytokines were upregulated, peaked on d 5, and then decreased to the control level, indicating that L. plantarum J26 could induce expression of the genes encoding these proinflammatory cytokines. Teichoic acids produced by L. plantarum are recognized as key immunomodulatory molecules involved in the regulation of the host immune response. To better understand the genetic basis of this immunomodulatory mechanism, we sequenced and analyzed the whole genome of L. plantarum J26. The genome of L. plantarum J26 contains a circular chromosome and 4 circular plasmids. Lactobacillus plantarum J26 was predicted to synthesize ribitol-type backbones of wall teichoic acid. Furthermore, orthologous average nucleotide identity (OrthoANI) values showed that the genome was highly similar (>98.00%) to other L. plantarum strains, especially to L. plantarum ST-III and JDM1. The genomic data of L. plantarum J26 provide a genetic basis to further elucidate its mechanism of immunoregulation and will facilitate its application in the functional dairy food industry.


Assuntos
Genoma Bacteriano , Lactobacillus plantarum/genética , Probióticos , Animais , Produtos Fermentados do Leite/microbiologia , Citocinas/metabolismo , Fatores Imunológicos/farmacologia , Lactobacillus plantarum/imunologia , Lactobacillus plantarum/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Probióticos/farmacologia , Ácidos Teicoicos/metabolismo , Sequenciamento Completo do Genoma
16.
Genome Biol ; 20(1): 158, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391098

RESUMO

BACKGROUND: Several genome-scale metabolic reconstruction software platforms have been developed and are being continuously updated. These tools have been widely applied to reconstruct metabolic models for hundreds of microorganisms ranging from important human pathogens to species of industrial relevance. However, these platforms, as yet, have not been systematically evaluated with respect to software quality, best potential uses and intrinsic capacity to generate high-quality, genome-scale metabolic models. It is therefore unclear for potential users which tool best fits the purpose of their research. RESULTS: In this work, we perform a systematic assessment of current genome-scale reconstruction software platforms. To meet our goal, we first define a list of features for assessing software quality related to genome-scale reconstruction. Subsequently, we use the feature list to evaluate the performance of each tool. To assess the similarity of the draft reconstructions to high-quality models, we compare each tool's output networks with that of the high-quality, manually curated, models of Lactobacillus plantarum and Bordetella pertussis, representatives of gram-positive and gram-negative bacteria, respectively. We additionally compare draft reconstructions with a model of Pseudomonas putida to further confirm our findings. We show that none of the tools outperforms the others in all the defined features. CONCLUSIONS: Model builders should carefully choose a tool (or combinations of tools) depending on the intended use of the metabolic model. They can use this benchmark study as a guide to select the best tool for their research. Finally, developers can also benefit from this evaluation by getting feedback to improve their software.


Assuntos
Bactérias/metabolismo , Genoma Bacteriano , Redes e Vias Metabólicas/genética , Software , Bordetella pertussis/genética , Bordetella pertussis/metabolismo , Genes Bacterianos , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Pseudomonas putida/genética , Pseudomonas putida/metabolismo
17.
Appl Microbiol Biotechnol ; 103(18): 7687-7702, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31388732

RESUMO

In recent years, there is an increasing interest from the winemaking industry for the use of mixed fermentations with Starmerella bacillaris (synonym Candida zemplinina) and Saccharomyces cerevisiae, due to their ability to modulate metabolites of oenological interest. The current study was carried out to elucidate the effect of this fermentation protocol on the growth and malolactic activity of lactic acid bacteria (LAB) used for malolactic fermentation (MLF) and on the chemical and volatile profile of Nebbiolo wines and their chromatic characteristics. To this end, two LAB species, namely Lactobacillus plantarum and Oenococcus oeni, were inoculated at the beginning and at the end of the alcoholic fermentation (AF) performed by pure and mixed yeast using the abovementioned yeasts. The different yeast inoculation protocols and the combination of species tested influenced greatly the interactions and behavior of the inoculated yeasts and LAB during AF and MLF. For both LAB species, inoculation timing was critical to how rapidly MLF started and finished. Fermentation inoculated with L. plantarum, at the beginning of the AF, completed MLF faster than those inoculated with O. oeni. The presence of Starm. bacillaris in mixed fermentation promoted LAB growth and activity, in particular, O. oeni. Furthermore, LAB species choice had a greater impact on the volatile and chromatic profile of the wines than inoculation time. These findings reveal new knowledge about the importance of LAB species choice and inoculation time to ensure fast MLF completion and to improve wine characteristics in mixed fermentation with Starm. bacillaris and S. cerevisiae.


Assuntos
Fermentação , Ácido Láctico/metabolismo , Lactobacillus plantarum/metabolismo , Malatos/metabolismo , Interações Microbianas , Oenococcus/metabolismo , Lactobacillales/crescimento & desenvolvimento , Lactobacillales/metabolismo , Vinho/análise , Vinho/microbiologia
18.
Ultrason Sonochem ; 59: 104724, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421618

RESUMO

Due to their nonpathogenic status, biosurfactants produced by Lactobacillus strains have been shown to have potential applicability in several industrial sectors, particularly food and pharmaceutical industries. However, products with high efficiency are needed to fulfill the demand for these biosurfactants. Therefore, the present study investigated kinetic parameters, biomass and biosurfactant production of Lactobacillus plantarum ATCC 8014 applying standard MRS and modified MRS (supplemented standard MRS by nitrogen and carbon sources) culture medium under various ultrasonic frequencies of 20, 25, 35, 45, 130 and 950 kHz to obtain more efficient conditions. The optimum conditions were found when using the modified MRS treated by the frequency of 25 kHz (the power of 7.4 W) for 30 min, which led to a significant effect on the growth rate (µmax, h-1) rather than control. Furthermore, this condition caused the highest population (10.07 ±â€¯0.1 log CFU/mL) and biomass concentration (4.33 ±â€¯0.06 g/L), and lowest surface tension (39.26 ±â€¯0.5 mN/m), leading to higher biosurfactant production. Hence, given the results of the present study, it can be established that controlled ultrasound exposure and supplementation of culture media using the main growth factors can intensify the microbial activity and the productivity of biological processes.


Assuntos
Biotecnologia/métodos , Lactobacillus plantarum/metabolismo , Tensoativos/metabolismo , Ondas Ultrassônicas , Biomassa , Cinética , Lactobacillus plantarum/fisiologia , Viabilidade Microbiana
19.
Food Microbiol ; 84: 103242, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421747

RESUMO

This paper describes a mixed fermentation model made by assembling block hosting models for the growth of lactic acid bacteria (Lactobacillus plantarum) and a yeast strain (Pichia kluyveri), metabolic production and the physical-chemical changes which occur during the fermentation of gowé. The growth model for P. kluyveri was developed on a synthetic medium following the gamma concept taking into account the effect of pH, temperature, concentrations in glucose, lactic acid and ethanol. Additional parameters for the previously defined L. plantarum growth model were also determined (glucose and ethanol concentrations). The model was validated in three different gowé processing conditions. Even if the model underestimates LAB growth, it explains what occurs in the product and enables in silico extrapolation to various fermentation conditions. The predicted hydrolysis rates of native and gelatinised starches showed that increasing malt content is not an efficient way to increase the sweetness of gowé in contrast to increasing the level of pre-cooking. The builing-block model developed in this study could be applied to many other fermented foods and particularly to non-alcoholic but acid and sweet cereal based beverages.


Assuntos
Fermentação , Lactobacillus plantarum/metabolismo , Modelos Biológicos , Pichia/metabolismo , Hidrólise , Lactobacillus plantarum/crescimento & desenvolvimento , Pichia/crescimento & desenvolvimento
20.
Food Microbiol ; 84: 103262, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421756

RESUMO

The organoleptic attributes of Prunus mahaleb, a fruit representing a new source of bioactive compounds, are so pronounced that it can be consider non-edible. This study was designed to evaluate the acceptance of P. mahaleb fruits after fermentation with different Saccharomyces cerevisiae and Lactobacillus plantarum protechnological strains. Four different bacterial and one yeast strains, as single or mixed starter formulation, were used to inoculate an aqueous suspension of P. mahaleb fruits. The fermented fruits and fermentation broths were subjected to physico-chemical characterization and the organoleptic properties of both samples were also assessed by a hedonic panel. The obtained results indicated that all the employed strains were able to grow and to ferment the matrix. However, the mixed starter FG69 + Li180-7 (L. plantarum/S. cerevisiae) had the best impact on sensory characteristics of P. mahaleb fruit and fermented medium. The adopted protocol allowed us to attain edible fruits and a new fermented non-dairy drink with valuable probiotic health-promoting properties. In our knowledge, this is the first study concerning the exploitation of P. mahaleb fruits. This investigation confirmed the potential of yeasts and lactic acid bacteria co-inoculation in the design of starter tailored for this kind of food applications.


Assuntos
Fermentação , Frutas/microbiologia , Lactobacillus plantarum/metabolismo , Prunus/microbiologia , Saccharomyces cerevisiae/metabolismo , Microbiologia de Alimentos , Malatos/análise , Probióticos
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