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1.
Molecules ; 26(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34684821

RESUMO

Currently, there is a growing demand for flavorings, especially of natural origin. It is worth paying attention to the biotechnological processes of flavor production, characterized by simplicity, high efficiency and relatively low cost. In this study, we analyzed the ability of the Galac tomyces geotrichum mold to transform by-products of the dairy industry: sour whey and buttermilk to complex flavour mixtures with pleasant, honey-rose aroma. Furthermore, the aroma complexity of the fermentation product has been carefully identified applying a sensomic approach involving the use of gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS) and stable isotope dilution assay (SIDA) to identify and quantify aroma compounds. Based on the calculation of odor activity value (OAV), 13 key aroma compounds were present in both tested variants. The highest OAVs were found for phenylacetaldehyde (honey-like) in the buttermilk variant (912) and 2-phenylethanol (rose-like) in the sour whey variant (524). High values of this indicator were also recorded for phenylacetaldehyde (319) and 3-methyl-1-butanol with a fruity aroma (149) in the sour whey culture. The other compounds identified are 3-methylbutanal (malty), 2,3-butanedione (cheesy), isovaleric acid (cheesy), 3-(methylthio)-propanal (boiled potato), butanoic acid (vinegar), (E)-2-nonenal (fatty), ethyl furaneol (burnt sugar), dimethyl trisulfide (cabbage), and acetic acid (vinegar).


Assuntos
Leitelho/análise , Leitelho/microbiologia , Microbiologia de Alimentos , Geotrichum/metabolismo , Odorantes/análise , Soro do Leite/química , Soro do Leite/microbiologia , Acetaldeído/análogos & derivados , Acetaldeído/análise , Biotecnologia , Biotransformação , Fermentação , Aromatizantes/metabolismo , Tecnologia de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Olfatometria , Álcool Feniletílico/análise , Paladar , Compostos Orgânicos Voláteis/análise
2.
Appl Microbiol Biotechnol ; 105(10): 4255-4268, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33988734

RESUMO

The present study aimed to elucidate the effect of subinhibitory concentrations (sub-MICs) of juniper essential oil (EO), α-pinene, and sabinene on the quorum-sensing (QS)-mediated proteolytic and lipolytic properties of Pseudomonas fluorescens KM24. These activities were verified under in situ conditions, in which sub-MICs of the agents altered the morphology of KM24 cells. RNA-Seq studies revealed key coding sequences (CDSs)/genes related to QS and the proteolytic/lipolytic activities of pseudomonads. In this work, all the examined agents decreased autoinducer synthesis and influenced the mRNA expression of the encoding acyltransferase genes lptA, lptD, and plsB. The highest reduction on the 3rd and 5th days of cultivation was observed for the genes lptD (-5.5 and -5.61, respectively) and lptA (-3.5 and -4.0, respectively) following treatment with EO. Inhibition of the lptA, lptD, and plsB genes by singular constituents of EO was on average, from -0.4 to -0.7. At 5 days of cultivation the profile of AHLs of the reference P. fluorescens KM24 strain consisted of 3-oxo-C14-HSL, 3-oxo-C6-HSL, C4-HSL, and N-[(RS)-3-hydroxybutyryl]-HSL, the concentrations of which were 0.570, 0.018, 3.744, and 0.554 µg ml-1, respectively. Independent of the incubation time, EO, α-pinene, and sabinene also suppressed the protease genes prlC (-1.5, -0.5, and -0.5, respectively) and ctpB (-1.5, -0.7, and -0.4, respectively). Lipolysis and transcription of the lipA/lipB genes were downregulated by the agents on average from -0.3 to -0.6. α-Pinene- and sabinene-rich juniper EO acts as an anti-quorum-sensing agent and can repress the spoilage phenotype of pseudomonads. KEY POINTS: Juniper EO, α-pinene, sabinene exhibited anti-QS potential toward KM24. RNA-Seq revealed key CDSs/genes related to QS/proteolytic/lipolytic activities of KM24. Agents at sub-MIC levels influenced the mRNA expression of QS/lipase/protease genes.


Assuntos
Juniperus , Óleos Voláteis , Pseudomonas fluorescens , Biofilmes , Óleos Voláteis/farmacologia , Pseudomonas fluorescens/genética , Percepção de Quorum
3.
J Agric Food Chem ; 68(39): 10799-10807, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32865406

RESUMO

Fermented products with a pleasant aroma and with strong honey, rose, and fruit odor notes were developed through the biotransformation of a medium containing sour or sweet whey with the addition of l-phenylalanine by the Galactomyces geotrichum mold. In order to obtain the strong honey-rose aroma, G. geotrichum strains were screened and fermentation conditions were optimized to achieve a preferable ratio (>1) of phenylacetaldehyde to 2-phenylethanol by the Ehrlich pathway. This allowed post-fermentation products with the ratio of concentrations of phenylacetaldehyde to 2-phenylethanol being 1.7:1. Additionally, the use of gas chromatography-olfactometry (GC-O) analysis and the calculation of odor activity values (OAVs) allowed 10 key odorants to be identified in post-fermentation products. The highest OAVs were found for phenylacetaldehyde with a honey odor in both sour and sweet whey cultures (3010 and 1776, respectively). In the variant with sour whey, the following compounds with the highest OAVs were 3-methyl-1-butanol (131), 3-(methylthio)-propanal (119), 3-methylbutanal (90), dimethyl trisulfide (71), 2,3-butanedione (37), and 2-phenylethanol (29). In the post-fermentation product with sweet whey, the following compounds with the highest OAVs were 3-(methylthio)-propanal (112), dimethyl trisulfide (69), and 2,3-butanedione (41).


Assuntos
Geotrichum/metabolismo , Odorantes/análise , Compostos Orgânicos Voláteis/metabolismo , Soro do Leite/metabolismo , Acetaldeído/análogos & derivados , Acetaldeído/análise , Acetaldeído/metabolismo , Cromatografia Gasosa , Fermentação , Geotrichum/química , Olfatometria , Fenilalanina/metabolismo , Compostos Orgânicos Voláteis/química
4.
Int J Food Microbiol ; 331: 108732, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-32521374

RESUMO

The present study aimed to evaluate the anti-quorum sensing (anti-QS) and anti-proteolytic potentials of tarragon essential oil (TEO) and its major compounds against food-associated Pseudomonas spp. The activities were verified by in vitro, in silico and in situ approaches. In this work, methyl eugenol (ME)- and ß-phellandrene (ß-PH)-rich TEO was investigated. TEO at subMIC increased the percentage of saturated fatty acids in the bacterial membranes (from 7 to 22%) and exhibited anti-quorum sensing via decreasing the efficiency of QS autoinducer synthesis [3-oxo-C12-HSL (from 2.028 µg/mL to

Assuntos
Artemisia/química , Óleos Voláteis/farmacologia , Proteólise/efeitos dos fármacos , Pseudomonas/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/isolamento & purificação , 4-Butirolactona/farmacologia , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Simulação por Computador , Peixes/microbiologia , Homosserina/análogos & derivados , Homosserina/isolamento & purificação , Homosserina/farmacologia , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Pseudomonas/isolamento & purificação
5.
Int J Food Microbiol ; 319: 108503, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-31923767

RESUMO

Thirty nine strains of Galactomyces geotrichum molds were isolated from a traditional fried cottage cheese and production of polyunsaturated fatty acids (PUFA) was assessed. Among them eleven strains produced an extracellular lipids enriched in n-6 and n-3 PUFA. The extracellular lipids produced by G. geotrichum strain 38 contained the highest amounts of total PUFA (24.3%), with the highest contribution of n-3 fatty acids (17.9%), where α-linolenic, eicosapentaenoic, docosapentaenoic and docosahexaenoic acids were the main contributors. To obtain maximal production of PUFA, composition of the medium consisted of 10 g/L rapeseed oil, 5 g/L yeast extract, 0.05 g/L K2HPO4, 0.17 g/L MgSO4, 0.015 g/L MnSO4, 0.015 g/L ZnSO4, 0.05 g/L FeSO4, and 10 mg/L vitamin B12. The optimal growth conditions at 30 °C involve: aeration at 1.5 vvm (volume of air per volume of broth per minute) at pH 6.5. The cheese produced under described conditions contained higher amount of n-3 PUFA (0.25 mg/g cheese) in comparison to control (0.01 mg/g). α-Linolenic acid predominated among n-3 fatty acids. Galactomyces geotrichum is a natural microflora of dairy products, and could be used to enrich food/cheese in deficient omega-3 lipids.


Assuntos
Queijo/microbiologia , Ácidos Graxos Ômega-3/biossíntese , Geotrichum/metabolismo , Animais , Ácidos Graxos Ômega-6/biossíntese , Geotrichum/classificação , Geotrichum/isolamento & purificação
6.
Nutrients ; 11(2)2019 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-30813404

RESUMO

Fried cottage cheese is a dairy product, popular in some parts of Poland. Proteomic analysis of a culture of the mold Galactomyces geotrichum 38 isolated from fried cottage cheese was performed using UHPLC/MS. From the proteins identified, we selected those involved in the biosynthesis of bioactive compounds and those useful in industry. In the G. geotrichum 38 culture, the production quantities of vitamin B2 (224 µg/L), ergosterol (54.63 mg/kg), and trehalose (0.91 g/L) were determined by HPLC. The identified proteins were also used to prepare a hypothetical fatty acid biosynthesis pathway, and the percentage of individual sphingolipids in the culture was determined. Sphingolipids are also bioactive compounds. During culturing of G. geotrichum 38, the percentage of three sphingolipids increased. The last step of the research was to prepare a model of fried cottage cheese. The mold G. geotrichum 38, used in the process of ripening fried cottage cheese, synthesized vitamin B2 and erogsterol, which influenced the nutritional value of the product.


Assuntos
Queijo/microbiologia , Microbiologia de Alimentos , Regulação Fúngica da Expressão Gênica/fisiologia , Geotrichum/metabolismo , Culinária , Ergosterol/biossíntese , Proteínas Fúngicas , Humanos , Proteômica , Riboflavina/biossíntese , Esfingolipídeos/biossíntese , Trealose/biossíntese
7.
J Agric Food Chem ; 66(10): 2443-2448, 2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28145120

RESUMO

Application of gas chromatography-olfactometry (GC-O) carried out on the volatile fraction isolated by solvent-assisted flavor evaporation (SAFE) and solid phase microextraction (SPME) from Lazur mold-ripened cheese revealed 17 odor-active compounds. The highest flavor dilution factor (FD) has been obtained for methanethiol (2048) with a burnt odor note and for 2(3)-methylbutanoic acid (2048) with a cheesy, pungent odor. Further quantitation of the 15 most aroma-active compounds allowed for calculation of their odor activity values (OAV). The highest OAVs were obtained for methanethiol (500), 3(2)-methylbutanoic acid (321), 3-(methylthio)propanal (210), 2,3-butanedione (65), dimethyl trisulfide (22), butanoic acid (20), 1-octen-3-ol (18), ( Z)-4-heptenal (14), dimethyl disulfide (14), dimethyl sulfide (13), phenylacetaldehyde (6), 2-ethyl-3,5-dimethylpyrazine (5), and acetic acid (4). An aroma recombination experiment showed slight differences in the perception of cheesy/sweaty and moldy/musty notes. To verify the influence of methyl ketones on the aroma profile of mold-ripened cheese, recombinant has been additionally supplemented with 2-pentanone, 2-heptanone, and 2-nonanone in concentrations determined in Lazur cheese. The aroma profile remained unchanged, which would suggest that methyl ketones, in this particular cheese, do not play a significant role in the formation of aroma.


Assuntos
Queijo/análise , Fungos/metabolismo , Odorantes/análise , Adulto , Queijo/microbiologia , Feminino , Fermentação , Aromatizantes/química , Aromatizantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Olfato , Paladar , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
8.
Acta Sci Pol Technol Aliment ; 16(1): 5-16, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28362468

RESUMO

The article reviews the properties of the Galactomyces geotrichum species, the mould that is most important for the dairy industry. G. geotrichum mould has been isolated from milk, cheeses and alcoholic beverage. Its presence in food products makes it possible to obtain a characteristic aroma and taste, which corresponds to the needs and preferences of consumers. G. geotrichum plays an important role in ecology, where the mould is employed for the degradation of various hazardous substances and wastewater treatment. It has also been found to have potential for biofuel production. In addition to this, G. geotrichum can be applicable in two further major areas: agriculture and health protection.


Assuntos
Laticínios/microbiologia , Saccharomycetales , Biodegradação Ambiental , Biocombustíveis/microbiologia , Biotecnologia , Microbiologia de Alimentos , Gerenciamento de Resíduos , Águas Residuárias/microbiologia
9.
N Biotechnol ; 36: 17-25, 2017 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-28043869

RESUMO

The aim of this study was to evaluate the ability of bacterial cultures isolated from cattle, poultry or pig faeces and manure to produce rhamnolipids, as well as to investigate the influence of interspecies communication on possible quantitative differences in the production of rhamnolipid congeners. Initial screening methods (oil spreading, drop collapse, haemolytic activity and emulsification activity) showed that approximately 36% of the 51 isolated cultures exhibited the ability to produce biosurfactants. Subsequent studies using a selected culturable mixed culture (which included Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli) revealed that only P. aeruginosa was able to produce this biosurfactant. HPLC-MS analysis showed that the surface active compounds were rhamnolipids. Further comparative studies confirmed that the total yield of rhamnolipids was notably higher in the bioreactor inoculated with the selected mixed culture (940.58±1.10mg/L) compared to the bioreactor inoculated with the axenic strain of P. aeruginosa (108.47±0.41mg/L). Twelve rhamnolipid congeners were identified during cultivation of the selected mixed culture, whereas six congeners were detected during cultivation of the sole axenic strain of P. aeruginosa. Furthermore, increased production of rhamnolipids was observed when the concentration of autoinducer molecules (AI-2) responsible for interspecies signaling increased, suggesting the influence of quorum-sensing communication on biosynthesis efficiency. This observation may be of importance for large-scale production of this biosurfactant, as it opens new possible solutions based on the use of mixed cultures or external addition of stimulating autoinducers.


Assuntos
Fezes/microbiologia , Glicolipídeos/biossíntese , Animais , Biotecnologia , Bovinos/microbiologia , Galinhas/microbiologia , Enterococcus faecalis/isolamento & purificação , Enterococcus faecalis/metabolismo , Escherichia coli/isolamento & purificação , Escherichia coli/metabolismo , Homosserina/análogos & derivados , Homosserina/metabolismo , Lactonas/metabolismo , Esterco/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/metabolismo , Percepção de Quorum , Tensoativos/metabolismo , Sus scrofa/microbiologia
10.
J Sci Food Agric ; 97(2): 659-668, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27144959

RESUMO

BACKGROUND: Knowledge regarding microaerophilic and anaerobic specific spoilage organisms (SSOs) is crucial for an appropriate evaluation of vacuum-packed ham. The objective of this study was to characterize the SSO community in vacuum-packed ham by a culture-dependent technique and MiSeq next-generation sequencing (NGS) platform. The relation between changes among the SSO group in the ham and changes in sensory characteristics of the product was also assessed. RESULTS: In the study, conventional microbiological analyses were employed in order to establish the participation of several groups of microorganisms in the deterioration of vacuum-packed ham. The diversity of the SSO group in the product was further assessed with the use of MiSeq NGS technology. The bacteria identified in sliced cooked ham belonged mostly to four phyla, namely Actinobacteria, Proteobacteria, Firmicutes and Bacteroidetes. A temperature of 4 °C favoured the development of mesophilic and psychrophilic/psychrotrophic flora, mainly Lactobacillaceae, Enterobacteriaceae and Micrococcaceae families. A high ratio of Brochothrix thermosphacta species and new, cold-tolerant Clostridium spp. was also observed. The growth of these microorganisms facilitated changes in the pH value and organoleptic characteristics of the product. CONCLUSION: This study confirms that the combination of culturing and MiSeq NGS technology improves the microbial evaluation of food. © 2016 Society of Chemical Industry.


Assuntos
Enterobacteriaceae/crescimento & desenvolvimento , Embalagem de Alimentos , Conservação de Alimentos , Armazenamento de Alimentos , Lactobacillaceae/crescimento & desenvolvimento , Carne/microbiologia , Micrococcaceae/crescimento & desenvolvimento , Animais , Biologia Computacional , Enterobacteriaceae/classificação , Enterobacteriaceae/isolamento & purificação , Fast Foods/análise , Fast Foods/microbiologia , Qualidade dos Alimentos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Concentração de Íons de Hidrogênio , Lactobacillaceae/classificação , Lactobacillaceae/isolamento & purificação , Carne/análise , Fenômenos Mecânicos , Micrococcaceae/classificação , Micrococcaceae/isolamento & purificação , Tipagem Molecular , Polônia , Análise de Componente Principal , Refrigeração , Sensação , Sus scrofa , Vácuo
11.
Food Chem ; 197(Pt A): 648-57, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26616999

RESUMO

Elderberry (EDB) Sambucus nigra L. is one of the oldest medicinal plants which is useful for therapeutic and nutritional purposes due to a large amount of biologically active constituents, including compounds with a high antioxidant capacity. The present study focused on the antioxidant potential of the colon-available EDB fruit extract, derived from the artificial gastrointestinal tract, with regard to human colonic mucosa cells cultured in vitro. Despite the significant loss of EDB bioactive compounds due to the digestion process, the colon-digested extract was able to reduce the excessive intracellular ROS production (22%) and oxidative DNA damage (46%) in the colon cells at a dose of 1 mg of freeze-dried EDB powder/ml. Moreover, the colon-digested EDB extract inhibited oxidant-induced mutagenicity (26%) in the Salmonella typhimurium TA102 strain, as determined by the Ames test. In conclusion, the current in vitro study confirmed that the fruits of S. nigra are capable of protecting colonic cells against the detrimental effects of oxidative stress.


Assuntos
Colo/citologia , Frutas/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Sambucus nigra/química , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular , Colo/efeitos dos fármacos , Colo/metabolismo , Dano ao DNA/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/toxicidade , Mucosa Intestinal/efeitos dos fármacos , Mutagênicos/toxicidade , Extratos Vegetais/análise , Espécies Reativas de Oxigênio/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/metabolismo
12.
J Sci Food Agric ; 96(12): 4037-47, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26710926

RESUMO

BACKGROUND: In the process of Pseudomonas fluorescens biofilm formation, N-acyl-l-homoserine lactone (AHL)-mediated flagella synthesis plays a key role. Inhibition of AHL production may attenuate P. fluorescens biofilm on solid surfaces. This work validated the anti-biofilm properties of p-coumaric and gallic acids via the ability of phenolics to suppress AHL synthesis in P. fluorescens KM120. The dependence between synthesis of AHL molecules, expression of flagella gene (flgA) and the ability of biofilm formation by P. fluorescens KM120 on a stainless steel surface (type 304L) was also investigated. RESULTS: Research was carried out in a purpose-built flow cell device. Limitations on AHL synthesis in P. fluorescens KM120 were observed at concentrations of 120 and 240 µmol L(-1) of phenolic acids in medium. At such levels of gallic and p-coumaric acids the ability of P. fluorescens KM120 to synthesize 3-oxo-C6-homoserine lactone (HSL) was not observed. These concentrations caused decreased expression of flgA gene in P. fluorescens KM120. The changes in expression of AHL-dependent flgA gene significantly decreased the rate of microorganism colonization on the stainless steel surface. CONCLUSION: Phenolic acids are able to inhibit biofilm formation. The results obtained in the work may help to develop alternative techniques for anti-biofilm treatment in the food industry. © 2015 Society of Chemical Industry.


Assuntos
4-Butirolactona/análogos & derivados , Ácidos Cumáricos/farmacologia , Ácido Gálico/farmacologia , Pseudomonas fluorescens/efeitos dos fármacos , 4-Butirolactona/biossíntese , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Flagelos/genética , Microbiologia de Alimentos , Regulação Bacteriana da Expressão Gênica , Humanos , Propionatos , Pseudomonas fluorescens/genética
13.
Biofouling ; 31(7): 587-97, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26313563

RESUMO

This study evaluated the effectiveness of selected disinfectants against bacterial cells within a biofilm using flow cytometry, the conventional total viable count test and scanning electron microscopy (SEM). A flow cytometric procedure based on measurement of the cellular redox potential (CRP) was demonstrated to have potential for the rapid evaluation of activity against biofilm and planktonic forms of microbes. Quaternary ammonium compound-based disinfectant (QACB) demonstrated a higher level of anti-microbial activity than a performic acid preparation (PAP), with mean CRP values against P. aeruginosa cells of 2 and 1.33 relative fluorescence units (RFU) vs 63.33 and 61.33 RFU for 8 and 24 h cultures respectively. Flow cytometric evaluation of the anti-biofilm activity demonstrated a higher efficacy of QACB compared to PAP for P. aeruginosa cells of 1 and 0.66 RFU vs 18.33 and 22.66 RFU for 8 and 24 h cultures respectively. SEM images of treated P. aeruginosa cells demonstrated disinfectant-specific effects on cell morphology.


Assuntos
Biofilmes , Enterococcus faecalis , Plâncton , Pseudomonas aeruginosa , Compostos de Amônio Quaternário/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Desinfetantes/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/fisiologia , Citometria de Fluxo/métodos , Microscopia Eletrônica de Varredura/métodos , Plâncton/efeitos dos fármacos , Plâncton/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia
14.
J Sci Food Agric ; 95(9): 1892-902, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25186016

RESUMO

BACKGROUND: Broccoli is a common vegetable recognized as a rich source of antioxidants. To date, research on the antioxidant properties of broccoli, predominantly conducted on extracts, has not considered the lesions of composition and this activity after gastrointestinal digestion. Here the stability of antioxidants during gastrointestinal digestion was evaluated in conjunction with the protective effects of broccoli sprouts (BS) against oxidative stress in human colon cells. RESULTS: The obtained data suggest that, among the biocompounds identified in BS, glucosinolates were mainly degraded under gastrointestinal digestion, while phenolics, particularly hydroxycinnamic acid derivatives, were the most resistant constituents. The antioxidant capacity of BS extract subjected to gastrointestinal digestion was similar to or higher than that determined for non-digested BS. Gastrointestinal digested BS extract exhibited reactive oxygen species (ROS)-inhibitory capacity in NCM460 human colon cells, with 1 mg mL(-1) showing an ROS clearance of 76.59%. A 57.33% reduction in oxidative DNA damage in NCM460 cells due to treatment with digested BS extract was observed. CONCLUSION: The results lend support to the possible application of BS as a rich source of antioxidants to improve the defensive system against oxidative stress in the human colon mucosa.


Assuntos
Antioxidantes/análise , Brassica/química , Colo/metabolismo , Digestão , Mucosa Intestinal/metabolismo , Modelos Biológicos , Plântula/química , Antioxidantes/efeitos adversos , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Brassica/economia , Brassica/crescimento & desenvolvimento , Linhagem Celular , Sobrevivência Celular , Fenômenos Químicos , Ácidos Cumáricos/efeitos adversos , Ácidos Cumáricos/análise , Ácidos Cumáricos/metabolismo , Dano ao DNA , Suplementos Nutricionais/efeitos adversos , Suplementos Nutricionais/análise , Liofilização , Fármacos Gastrointestinais/efeitos adversos , Fármacos Gastrointestinais/análise , Fármacos Gastrointestinais/isolamento & purificação , Fármacos Gastrointestinais/metabolismo , Glucosinolatos/efeitos adversos , Glucosinolatos/análise , Glucosinolatos/metabolismo , Humanos , Estresse Oxidativo , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Plântula/crescimento & desenvolvimento
15.
Acta Biochim Pol ; 61(4): 759-63, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25473655

RESUMO

Study presented here demonstrates the ability of three newly isolated strains, obtained from environmental probes (manure, bottom sediment, and food waste) and identified as Clostridium bifermentans, Clostridium butyricum, and Hafnia alvei, to synthesize 1,3-propanediol (1,3-PD), organic acids (such as lactic, acetic, fumaric, succinic, and butyric acids), and ethanol from glycerol. The production of 1,3-PD as well as the glycerol pathways in C. bifermentans and H. alvei cells have not been investigated and described yet by others. Moreover, there is no data in the available literature on the products of glycerol utilization by H. alvei and there is only some incoherent data (mainly from the first half of the twentieth century) about the ability of C. bifermentans to carry out glycerol degradation. Additionally, this study presents complete hypothetical glycerol pathways and the basic fermentation kinetic parameters (such as yield and productivity) for both strains as well as for the newly isolated C. butyricum strain.


Assuntos
Clostridium bifermentans/metabolismo , Clostridium butyricum/metabolismo , Propilenoglicóis/metabolismo
16.
J Biosci Bioeng ; 118(6): 651-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24994472

RESUMO

The purpose of these investigations was to evaluate the reduction capability of phenolic acids (ferulic, chlorogenic, gallic, and p-coumaric acids) on indole acetic acid synthesis by food-associated Pseudomonas fluorescens KM05. Specific genetic primer for the type III secretion system (TTSS) in P. fluorescens KM05 was designed and the influence of phenolic acids on its expression was investigated. In the work the ferulic and chlorogenic acids at the concentration of 0.02 and 0.04 µg/ml affected on bacterial growth pattern and the signal molecules production. The phenolic acids, that were appreciable effective against P. fluorescens KM05 indole acetic acid production, significantly suppressed TTSS gene.


Assuntos
Sistemas de Secreção Bacterianos/efeitos dos fármacos , Sistemas de Secreção Bacterianos/genética , Microbiologia de Alimentos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Hidroxibenzoatos/farmacologia , Ácidos Indolacéticos/metabolismo , Pseudomonas fluorescens/efeitos dos fármacos , Pseudomonas fluorescens/metabolismo , Ácido Clorogênico/farmacologia , Ácidos Cumáricos/farmacologia , Ácido Gálico/farmacologia , Regulação Bacteriana da Expressão Gênica/genética , Oxirredução , Propionatos , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/crescimento & desenvolvimento , Transdução de Sinais/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/genética , Virulência/efeitos dos fármacos
17.
Springerplus ; 2(1): 44, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23503672

RESUMO

Clostridium bifermentans strains, isolated from a manure, were examinated for their ability to produce lactic acid from PY medium with glycerol under different pH conditions and when PY medium was supplemented with saccharides such as fructose, sorbitol, glucose, mannose, mannitol, maltose, xylose, raffinose, and arabinose. In the last test performed, the ability of investigated strains to produce lactic acid from mixed carbon source (glycerol plus saccharide) was checked. The strains of Cl. bifermentans, designated as CB 371, CB 374, and CB 376 grew and produced lactic acid on PY medium irrespective of pH and the carbon source used. The optimal lactic acid production on PY medium with glycerol was obtained at pH of 7.0 in case of CB 371 and 376 (19.63 g/L and 16.65 g/L, accordingly) and at pH 8.0 in case of CB 374 (13.88 g/L). The best productivity of lactic acid on PY media by CB 371, CB 374, and CB 376 (above 30 g/L) was observed when mannitol was used as a carbon source. The mixed carbon source did not increase productivity of lactic acid by Cl. bifermentans. The yield of lactic acid was approximately equal to the yield of lactic acid obtained on the medium with only glycerol and lower than in medium with only mannitol. Thus, from the environmental point of view it is more beneficial to use the medium with waste-type material only, such as glycerol.

18.
Bioelectrochemistry ; 87: 50-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22503710

RESUMO

CuO∙SiO(2) hybrid oxide precipitated on a semi-technical scale was thoroughly characterised in terms of physicochemical properties. Its particle size distribution and SEM analysis were performed to establish dispersion and surface morphology. Chemical analysis provided information on the content of CuO and SiO(2) oxides in the hybrid systems. The oxide systems were also subjected to elemental analysis. Zeta potential determinations were evaluated to obtain information regarding the interactions between colloidal particles. The stability of copper silicates' water dispersions was estimated on the basis of zeta potential measurements. The obtained oxide systems were used as components of polymer composites with polyester resins, which were subjected to mechanical tests and bactericidal tests against Pseudomonas aeruginosa, a well known biofilm-forming microorganism. The anti-adhesive activity of the CuO·SiO(2) enriched polymers was assessed using a 9-degree scale of adhesion. A significant reduction in the P. aeruginosa biofilm development rate was achieved for Palatal A 400-01 resins enriched with both 2 and 8 phr of the filler. In the case of Aropol M 105 TB resins the introduction of CuO∙SiO(2) caused inhibition of bacterial colonisation but to a smaller extent. These results strongly indicate that the biological activity of Cu was maintained. The release of copper ions into the local environment was examined by atomic absorption spectrometry (AAS). Maximum values of 1.621 and 5.934 mg/dm(3) of released copper were detected. The surface composition of both resins studied by energy dispersive X-ray spectroscopy (EDS) contributed to the data suggesting homogenous distribution of Si; however copper seemed to form local aggregates. The presented results may be of great significance for those dealing with materials tailored for specific needs.


Assuntos
Materiais Biocompatíveis/síntese química , Biofilmes/efeitos dos fármacos , Cobre/química , Pseudomonas aeruginosa/efeitos dos fármacos , Dióxido de Silício/química , Aderência Bacteriana/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Biofilmes/crescimento & desenvolvimento , Coloides , Teste de Materiais , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Pseudomonas aeruginosa/crescimento & desenvolvimento , Resinas Sintéticas/química , Silicatos/química , Espectrometria por Raios X , Espectrofotometria Atômica
19.
J Biosci Bioeng ; 113(5): 631-3, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22300717

RESUMO

A selective isolation procedure of clostridial strains from natural samples able to convert glycerol to 1,3-propanediol (1,3-PD) and organic acids was investigated. The modified PY medium of high concentration of NaHCO(3) was shown to be highly selective for Clostridium bifermentans. Obtained isolates produced mainly 1,3-PD, lactic, acetic, and formic acids from glycerol.


Assuntos
Clostridium bifermentans/isolamento & purificação , Microbiologia Industrial/métodos , Microbiologia Ambiental , Glicerol/metabolismo , Propilenoglicóis/metabolismo
20.
Postepy Hig Med Dosw (Online) ; 64: 582-9, 2010 Nov 25.
Artigo em Polonês | MEDLINE | ID: mdl-21109710

RESUMO

The metabolism of a high density population of bacteria is regulated by a quorum sensing mechanism. Cell-to-cell communication of microorganisms regulates the process of production of pathogenicity factors including formation and differentiation of bacterial biofilms. The role of the quorum sensing system in the expression of virulence features is described in this paper. The possibility of application of the quorum sensing mechanism in medicine is also discussed.


Assuntos
Biofilmes , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Negativas/patogenicidade , Percepção de Quorum/fisiologia , Virulência , Humanos
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