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1.
Int J Biol Macromol ; 253(Pt 3): 126944, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37722646

RESUMO

Exopolysaccharide (EPS), as a secondary metabolite of microorganisms, has been commonly used in the dairy industry to replace the traditional stabilizers. However, the EPS production by microorganism is generally low, which limits its application. A litchi polysaccharide (Lzp2-2) with the promoting effect on EPS production by Weissella confusa was purified. The SEM and FT-IR analysis indicated that Lzp2-2 displayed a compact netlike structure and typical bands of carbohydrates. The structure of Lzp2-2 was further elucidated, which was comprised of a major backbone structure [→3)-ß-D-Galp-(1→6)-ß-D-Galp-(1 â†’ 6)-ß-D-Galp-(1 â†’ 3)-ß-D-Glcp-(1 â†’ 6)-α-D-Glcp-(1 â†’ 3)-α-D-Glcp-(1→] linked with two side chains [α-L-Araf-(1 â†’ 5)-α-L-Araf-(1→, and ß-D-Glcp-(1 â†’ or α-L-Araf-(1→] at the O-3 and O-6) of ß-D-Galp-(1→, respectively. Finally, Lzp2-2 was applied as an additive to the medium of yoghurt fermented by W. confusa. The results indicated Lzp2-2 not only promoted the EPS production to improve the viscosity, texture and mouthfeel of yoghurt, but also facilitated the generation of other secondary metabolites (volatile organic compounds), thus elevating the flavor of yoghurt.


Assuntos
Litchi , Weissella , Espectroscopia de Infravermelho com Transformada de Fourier , Polissacarídeos/química , Weissella/química
2.
Int J Biol Macromol ; 246: 125631, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37399863

RESUMO

Lactic acid bacteria of the genus Weissella contribute to spontaneous fermentation in, e.g., sourdough or sauerkraut, but are not registered as starter cultures because of their pending safety assessment. Some strains are able to produce high amounts of exopolysaccharides. This study aims to demonstrate the techno-functionality of five dextrans from W. cibaria DSM14295, produced under varying cultivation conditions, with respect to structural and macromolecular properties. A maximum of 23.1 g/L dextran was achieved by applying the "cold shift" temperature regime. The dextrans differed in molecular mass (9-22∙108 Da, determined by HPSEC-RI/MALLS), intrinsic viscosity (52-73 mL/g), degree of branching (3.8-5.7 % at position O3, determined by methylation analysis) and their side chain length and architecture, determined by HPAEC-PAD after enzymatic hydrolysis. Stiffness of acid gels from milk spiked with these dextrans increased linearly with dextran concentration. Principal component analysis showed that dextrans produced in a semi-defined medium are primarily described by moisture sorption and branching properties, whereas dextrans produced in whey permeate were similar because of their functional and macromolecular properties. Overall, dextrans from W. cibaria DSM14295 have a high potential because of the high production yield and their functionality which can be tailored by the conditions during fermentation.


Assuntos
Weissella , Weissella/química , Dextranos/química , Fermentação , Temperatura Baixa
3.
Int J Biol Macromol ; 212: 193-201, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35594939

RESUMO

Steel corrosion is a global issue that affects safety and the economy. Currently, the homopolysaccharide (HoPS) structure of a novel lactic acid bacterium (LAB) is under study, as well as its application as a green corrosion inhibitor. Weissella cibaria FMy 2-21-1 is a LAB strain capable of producing HoPS in sucrose enriched media. The isolated and purified HoPS was characterized by different spectroscopic analyses as a linear α-1,6 dextran adopting a random coil conformation, with high molecular weight and extended size in water. The polysaccharide showed a semi-crystalline organization, which is a requirement for film formation. Its biocoating showed a grainy network structure, with a slightly lesser hydrophobic role in the aqueous environment than in the ionic one. The electrochemical measurements of the steel-HoPS coating showed that the biopolymer layer acts as an anodic-type corrosion inhibitor, with high resistance to corrosion by water and with chloride ions which prevent pitting, a corrosion process typical of bare steel. Few reports have cited the application of LAB HoPS as corrosive coating inhibitors. This work is the first to explore the influence of a structurally characterized dextran from Weissella cibaria strain as a potential steel corrosion inhibitor in ionic environments.


Assuntos
Dextranos , Weissella , Corrosão , Dextranos/química , Aço/química , Água , Weissella/química
4.
Int J Biol Macromol ; 204: 677-684, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35181327

RESUMO

An EPS produced by Weissella confusa H2 was purified through Sephadex G-100, and the preliminary structure characteristics and biological activities of H2 EPS were analyzed. Molecular mass of purified H2 EPS was 2.705 × 106 Da as measured with gel permeation chromatography (GPC). Composition of monosaccharides, nuclear magnetic resonance (NMR) spectroscopy spectroscopy and fourier transform infrared (FT-IR) showed that the EPS was a linear homopolysaccharide, mainly constituted of glucose and it is suggested that the EPS was dextran with α-(1 â†’ 6) glycosidic bonds and a few α-(1 â†’ 3) branches. Atomic force micrograph (AFM) and scanning electron microscopy (SEM) analysis of dextran further revealed sheets branched microstructure anchored with many irregular protuberances in aqueous solution. The XRD pattern reflected non-crystalline amorphous nature. In addition, the solubility, water-holding capacity, thermal property, rheological property and heavy metal chelating activity of the purified H2 dextran were determined. The dissolution percentage and water holding capacity of the dextran were 98.78 ± 1.37% and 426.03 ± 7.26%, respectively. The dextran exhibited good hydrophilicity, thermal stability and heavy metal chelating activity. Rheological studies exhibited rotational speed, pH, temperature, metal ions solutions dependent semiviscous nature. These results support its use as an additive in the food and environmental protection fields.


Assuntos
Dextranos , Weissella , Dextranos/química , Peso Molecular , Polissacarídeos Bacterianos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Weissella/química
5.
Int J Biol Macromol ; 199: 17-23, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-34952097

RESUMO

In this study, an exopolysaccharide (EPS) was produced by Weissella cibaria NC516.11 isolated from distiller grains of Chinese Baijiu. The structural characterization of EPS determined using fourier transform infrared spectra and nuclear magnetic resonance spectra demonstrated that W. cibaria NC516.11 had α-(1 â†’ 6) (93.46%) d-glucose linkages with a few α-(1 â†’ 3) (6.54%) d-glucose linked branches. The monosaccharide composition of the EPS was glucose, and its molecular weight was 2.82 × 106 Da. Scanning electron microscopy showed that the microstructure of EPS had a three-dimensional structure at low magnification and a particle structure that protruded from the surface at high magnification. The addition of EPS into dough can promote the cross-linking of starch molecules and increase the water-holding capacity. Dynamic rheology indicated that the aqueous solution of EPS is a pseudoplastic fluid, and the higher the concentration of EPS, the greater the viscosity. The addition of EPS to the gluten-free dough showed G' > G″, which could increase the viscoelastic properties of the dough and enhance the gluten network.


Assuntos
Polissacarídeos Bacterianos , Weissella , Glutens , Peso Molecular , Polissacarídeos Bacterianos/química , Reologia , Weissella/química
6.
Food Chem ; 362: 130221, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34098436

RESUMO

Exopolysaccharides (EPS) were produced by four newly isolated lactic acid bacteria strains, then further extracted, separated and characterised under standardised conditions. Using a sucrose carbon source, these LAB strains belonging to Weissella confusa/cibaria produced EPS with a dextran high molecular weight fraction. The obtained yields of EPS ranged from 3.2 g/L to 47.1 g/L and outstandingly high yields were obtained using Weissella confusa/cibaria 3MI3 isolated from spontaneous spelt sourdough. After purification the influence of EPS-dextran of molar mass 3,244,000 g/mol on resistant starch formation in wheat starch pastes and pasted samples after temperature-cycled storage was examined. Size exclusion chromatography with post-column derivatisation revealed that a 1.5% share of EPS dextran limited formation of high molar mass resistant starch in starch pastes during storage. This work provides new insight on hindering resistant starch formation by using EPS, which could be efficiently produced in sourdough, thus improving the properties of sourdough bread.


Assuntos
Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/isolamento & purificação , Amido/química , Triticum , Weissella/metabolismo , Pão/análise , Fracionamento Químico , Fermentação , Armazenamento de Alimentos , Amido Resistente , Sacarose/metabolismo , Triticum/química , Triticum/microbiologia , Weissella/química , Weissella/isolamento & purificação
7.
Int J Biol Macromol ; 178: 306-315, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33652047

RESUMO

In this study, exopolysaccharides (EPSs) produced by Weissella confusa XG-3 were characterized. The monosaccharide composition of XG-3 EPS was determined to include glucose according to GC data, and its molecular weight was 3.19 × 106 Da, as determined by HPLC. Scanning electron microscopy (SEM) revealed a smooth, porous, and branched structure, and atomic force microscopy (AFM) confirmed the presence of round lumps and chains on irregular surfaces of XG-3 EPS. The results of the Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) analyses suggested that XG-3 EPS is a linear α-(1,6)-linked dextran. X-ray diffraction (XRD) data confirmed the noncrystalline amorphous structure, and the results of the Congo red assay corresponded to the random coiled chain conformation of XG-3 dextran. XG-3 dextran exhibited good radical scavenging activity and reducing power and possessed high thermal stability, with a degradation temperature (Td) of 306.8 °C. The absolute value of the zeta potential and particle size of XG-3 dextran continually increased with increasing dextran concentration. The water contact angle showed that XG-3 dextran had relatively high hydrophobicity in the presence of sucrose. XG-3 dextran stimulated the growth of Lactobacillus spp. and Bifidobacterium spp. These findings indicate that XG-3 dextran has unique characteristics and can be potentially applied as a food additive and an antioxidant.


Assuntos
Dextranos/química , Sequestradores de Radicais Livres/química , Polissacarídeos Bacterianos/química , Weissella/química
8.
Int J Biol Macromol ; 164: 2964-2973, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32853618

RESUMO

Exopolysaccharides (EPS) from lactic acid bacteria (LAB) are much diversed in structure, composition and applications which also adding a great commercial potential due to its generally recognized as safe (GRAS) status. LAB genus such as Lactobacillus, Leuconostoc, Streptococcus, Weissella, Lactococcus are known to produce EPS. Among this genus, Weissella is enormously reported for diversity and high production of EPS with wide range of industrial applications and bio-functional properties. This review summarize in detail about the Weissella EPS from genus to functional application. Physico-chemical characterization from production, purification step to structural elucidation of Weissella EPS is comprehensively discussed along with their properties. Weissella genus has revealed various EPS with significant functional potentials, making massive application in food and pharma industries as viscosifiers, biothickener, emulsifiers and stabilizers. In addition to this, biological properties of these EPS revealed multiple health promoting properties which can be explored for further applications in food and pharmaceutical sectors.


Assuntos
Polissacarídeos Bacterianos/isolamento & purificação , Polissacarídeos Bacterianos/farmacologia , Weissella/química , Indústria Farmacêutica , Indústria Alimentícia , Promoção da Saúde , Humanos
9.
Int J Biol Macromol ; 161: 648-655, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32512101

RESUMO

An exopolysaccharide (EPS) producer slimy-mucoid type colony was isolated from sourdough and identified as Weissella cibaria MED17. The 1H and 13C NMR spectra of EPS MED17 demonstrated that this EPS was a dextran type glucan ((1 â†’ 6)-linked α-D-glucose core structure) containing (1 â†’ 3)-linked α-D-glucose branches and proportion of (1 â†’ 6)-linked α-D-glucose units to (1 â†’ 3)-linked α-D-glucose units was 94.3:5.7%. The FTIR analysis also confirmed the (1 â†’ 6)-linked α-D-glucose linkage. A high level of thermal stability was observed for glucan MED17 as no degradation up to 300 °C was observed by TGA and DSC analysis. The XRD analysis of glucan MED17 showed its semi- crystalline nature and its compact sheet-like morphology was observed by SEM analysis. Finally, antioxidant characteristics of glucan MED17 were determined by ABTS and DPPH radical scavenging activity tests that revealed a moderate antioxidant activity of glucan MED17. These findings show potential techno-functional characteristics of glucan MED17.


Assuntos
Sequestradores de Radicais Livres , Glucanos , Polissacarídeos Bacterianos , Weissella/química , Configuração de Carboidratos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Glucanos/química , Glucanos/isolamento & purificação , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/isolamento & purificação
10.
J Food Sci ; 85(2): 394-403, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31976556

RESUMO

The delivery of active probiotic cells in capsules can reduce probiotic cell loss induced by detrimental external factors during digestion. In this study, we determined the optimal conditions for the encapsulation of Weissella cibaria JW15 (JW15) within calcium and polyethylene glycol (PEG)-alginate with chicory root extract powder (CREP). JW15 was encapsulated as the core material (109 cells/mL, 2 mL/min), and a solution containing a mixture of 1.5% sodium alginate and 1% CREP was extruded into a receiving bath with 0.1 M calcium chloride (CaCl2 ) and 0.05% PEG. Capsule morphology and size were measured using optical microscopy. The optimal air pressure and frequency vibration for capsules containing alginate only (Al) were 200 mbar and 200 Hz, respectively and 100 mbar and 350 Hz for capsules containing alginate with CREP (Ch), respectively. The voltage for both capsules types was fixed at 1.35 kV. Then, the capsules were incubated in a simulated gastrointestinal (GI) system for 6 hr at 37 °C. The addition of PEG in a CaCl2 hardening solution led to degradation of the Ch capsule (Ch-PEG) and the release of cells into the small intestine vessel in the simulated GI system. By contrast, the cells were trapped within the Al capsules. Based on these data, effective encapsulation using alginate with CREP and PEG can enable JW15 to be released at a targeted anatomical site of activity within the GI system, thereby, enhancing the efficacy of probiotic cells. These protective effects can be leveraged during the development of probiotic products. PRACTICAL APPLICATION: Weissella cibaria JW15 (109 cells/mL) was encapsulated in biodegradable and biocompatible capsules, prepared by mixing 1.5% alginate with 1% chicory root extract powder (CREP) in 0.1 M CaCl2 and 0.05% PEG using an encapsulator. The optimal processing parameters were as follows: pressure, 100 mbar; vibration frequency, 350 Hz; voltage, 1.35 kV; and core flow rate, 2 mL/min. When the resulting capsules were subjected to a simulated gastrointestinal system for 6 hr, the cells were released into the small intestine, and up to 95% cell viability was preserved. These results suggest that capsules made from alginate with CREP and formulated using calcium and PEG are a promising delivery system for probiotic cells.


Assuntos
Alginatos/química , Cichorium intybus/química , Composição de Medicamentos/métodos , Extratos Vegetais/química , Probióticos/química , Weissella/química , Cápsulas/química , Cápsulas/metabolismo , Trato Gastrointestinal/metabolismo , Humanos , Viabilidade Microbiana , Modelos Biológicos , Raízes de Plantas/química , Probióticos/metabolismo
11.
Int J Biol Macromol ; 143: 305-313, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31816378

RESUMO

Weissella confusa is a commonly found species in boza, a highly viscous beverage obtained from fermented cereals. Exopolysaccharide (EPS) produced by Weissella confusa C19 was characterized and the role of different cereals on its rheological characteristics were studied. Thus, the effect of the type of cereals on textural characteristics of boza for standard boza production and the fate of W. confusa during fermentation were assessed. W. confusa C19 EPS consisted of glucose, sucrose and 1.7 mg/kg protein. Structural characterization of water-soluble dextran was determined by 1H NMR, functional groups were identified by Fourier transform infrared spectroscopy (FT-IR) and the crystal structure was determined by X-ray diffraction (XRD). After EPS characterization, different cereal-based media including maize, oat, rice and wheat were used for the growth and EPS production of the bacterium. The rheologial properties of EPS obtained from different cereal-based media showed that the steady shear behavior of EPS was pseudoplastic. W. confusa C19 is a unique strain that can adapt to the environment containing high sugar to produce high amounts of polysaccharides. Besides new information on EPS from W. confusa origin, this study showed that the amount of dextran increased using solid media fortified with different cereals.


Assuntos
Dextranos/farmacologia , Grão Comestível/química , Reologia/métodos , Weissella/química , Dextranos/biossíntese , Dextranos/química , Fermentação , Espectroscopia de Ressonância Magnética , Polissacarídeos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Sacarose/química , Sacarose/farmacologia , Triticum/química
12.
Int J Biol Macromol ; 143: 797-805, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31715230

RESUMO

The present study focused on production, optimization and characterization of exopolysaccharide (EPS) from Weissella confusa MD1. The purified EPS MD1 was also evaluated for in vitro biological activities. The maximum yield of EPS (10.07 ± 0.32 g/L) was obtained with optimized culture conditions of 35 °C at pH 6.5 for 36 h with 4% (w/v) galactose and 1% (w/v) ammonium nitrate supplemented in MRS broth. The crude EPS was purified with diethylamino ethanol-Sepharose Fast Flow column and Sephadex-G 75 column. The physicochemical and functional characterization of the EPS was done by high-performance thin-layer chromatography (HPTLC), high-performance gel permeation chromatography (HPGPC), fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), thermo gravimetric and differential scanning calorimetric (TG-DSC) analysis, x-ray diffraction (XRD) and scanning electron microscopy (SEM). HPGPC analysis showed molecular weight of purified EPS MD1 as 2.909 KDa. Monosaccharide analysis showed that EPS was a novel mannan with mannose as the only monomeric unit present, suggesting EPS to be a homopolysaccharide containing â†’ 6) α-Man p (1 â†’ linkages. Microstructure studies by SEM showed MD1 EPS has globular and porous structure. The purified EPS MD1 exhibited higher thermal stability having degradation temperature around 267.74 °C with melting enthalpy value (Δ H) of 337.7 J/g. The EPS showed promising antioxidant activities with excellent antibiofilm activity against Staphylococcus aureus, Listeria monocytogenes, Salmonella enterica and Salmonella typhi. These striking physicochemical characteristics features and bioactivities of EPS would serve as potential candidate in food processing industry to be used as food adjunct in foods with health benefits. This is the first study reporting a mannan homopolysaccharide from Weissella sp. to be structurally characterized.


Assuntos
Mananas/farmacologia , Polissacarídeos Bacterianos/farmacologia , Weissella/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Compostos de Bifenilo/química , Carbono/farmacologia , Sequestradores de Radicais Livres/farmacologia , Espectroscopia de Ressonância Magnética , Mananas/isolamento & purificação , Mananas/ultraestrutura , Testes de Sensibilidade Microbiana , Peso Molecular , Monossacarídeos/análise , Nitrogênio/farmacologia , Picratos/química , Polissacarídeos Bacterianos/isolamento & purificação , Polissacarídeos Bacterianos/ultraestrutura , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Difração de Raios X
13.
Curr Pharm Biotechnol ; 20(9): 766-771, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244418

RESUMO

BACKGROUND: The development of antibiotic resistance amongst bacterial pathogens and a population explosion, e.g. in countries such as Indonesia, are two issues the world is facing today. These issues have stimulated interest in the development of new antimicrobial therapeutic agents and contraceptive strategies, such as novel spermicides. Bacteriocins, which are bacterially-derived antimicrobial peptides, may fulfill some of the criteria for these new agents. METHODS: Weissella confusa MBF8-1, originally isolated from a homemade soy product, exhibits antibacterial activity that was subsequently found to be plasmid-encoded, presumably by three peptides Bac1, Bac2 and Bac3. In the present study, we tested cell-free MBF8-1 bacteriocin preparations and chemically-synthesized versions of Bac1, Bac2 and Bac3 peptides for (i) its antibacterial activity against the indicator bacterium Leuconostoc mesenteroides and (ii) its ability to affect the motility of spermatozoa. Nisin, a known lantibiotic bacteriocin, was used as the control. RESULTS: Here, we demonstrate that synthetic Bac1, in combination with synthetic Bac2, was sufficient to inhibit the growth of L. mesenteroides and affect sperm motility. However, the presence of all three synthetic peptides, s-Bac1, s-Bac2 and s-Bac3, was required for full potency. CONCLUSION: In summary, the bacteriocin-like peptides of W. confusa MBF8-1 have the potential to be developed as a narrow-spectrum antimicrobial agent and a novel spermicidal agent.


Assuntos
Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermicidas/farmacologia , Weissella/química , Antibacterianos/isolamento & purificação , Bacteriocinas/isolamento & purificação , Humanos , Nisina/farmacologia , Plasmídeos , Espermicidas/isolamento & purificação
14.
Int J Biol Macromol ; 120(Pt A): 1315-1321, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30194998

RESUMO

An exopolysaccharide (EPS) was produced by Weissella cibaria YB-1 isolated from pickle Chinese cabbage. The EPS was purified and characterized. The monosaccharide composition of the EPS was glucose, and its molecular mass was 3.89 × 106 Da, as determined by gas chromatography (GC) and high performance liquid chromatography (HPLC). The structural characterization of purified EPS determined by Fourier transform infrared (FT-IR) spectra and nuclear magnetic resonance (NMR) spectra demonstrated that W. cibaria YB-1 synthesized a linear dextran that predominately had α-(1 → 6) glycosidic linkages with only a few α-(1 → 3) (4.3%) linked branches. The water solubility index (WSI), water holding capacity (WHC) and emulsifying activity (EA) of YB-1 dextran were 95.23 ±â€¯4.45, 287.84 ±â€¯16.23 and 84.43 ±â€¯3.65%, respectively. The in-vitro antioxidant activities of the dextran showed good scavenging effects on superoxide anion radical and hydroxyl radical.


Assuntos
Brassica/microbiologia , Polissacarídeos/isolamento & purificação , Weissella/química , Dextranos/química , Fermentação , Peso Molecular , Polissacarídeos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Weissella/patogenicidade
15.
Molecules ; 23(8)2018 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-30096901

RESUMO

Recently, studies have explored the use of probiotics like the Weissella cibaria strain, CMU (oraCMU), for use as preventive dental medicine instead of chemical oral care methods. The present study was conducted to investigate the antibacterial properties of the cell-free supernatant (CFS) from this bacterium. Cell morphology using the scanning electron microscope, and the antibacterial effect of CFS under various growth conditions were evaluated. The production of hydrogen peroxide, organic acids, fatty acids, and secretory proteins was also studied. Most of the antibacterial effects of oraCMU against periodontal pathogens were found to be acid- and hydrogen peroxide-dose-dependent effects. Lactic acid, acetic acid, and citric acid were the most common organic acids. Among the 37 fatty acids, only 0.02% of oleic acid (C18:1n-9, cis) was detected. Proteomic analysis of the oraCMU secretome identified a total of 19 secreted proteins, including N-acetylmuramidase. This protein may be a potential anti-microbial agent effective against Porphyromonas gingivalis.


Assuntos
Antibacterianos/farmacologia , Saúde Bucal , Probióticos/farmacologia , Weissella/química , Ácidos Carboxílicos/metabolismo , Ácidos Graxos/biossíntese , Peróxido de Hidrogênio/metabolismo , Cinética , Proteoma/metabolismo , Weissella/citologia , Weissella/crescimento & desenvolvimento , Weissella/ultraestrutura
16.
J Biosci Bioeng ; 126(6): 769-777, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30042003

RESUMO

Weissella cibaria 27 (W27) is a new lactic acid bacterium which has been screened from kimchi, and is important in diary fermentation. This is first-attempt to understand the effects of sucrose and achieve the highest exopolysaccharide (EPS) productivity from W27. The metabolic compounds of lactic acid, acetic acid and ethanol are at similar levels when the cultures with glucose or lactose; except for EPS is significantly increased up to 24.8 g/L with 60 g/L of sucrose. Scanning electron microscopy (SEM) results reveal cell length changing shorter after sucrose addition. By Taguchi's approach, an L9 orthogonal array was adopted to evaluate the effects of culture were ranked according to the EPS production as temperature > time > initial pH, in which optimal conditions were at 22°C and pH 6.2 for 24 h. The major composition of EPS is dextran of α-1,6 glycosidic linkage with molecular weight of 1.2 x 107 Da by nuclear magnetic resonance (NMR) and high-performance size-exclusion chromatography (HPSEC) analysis. The surface property of W27 induced by sucrose is become more hydrophobic to better inhibit bacteria. The simple cultural approach for this new dextran producing strain, W27, has potential in the food, feed, antibacterial agent, and cosmetic industry.


Assuntos
Antibacterianos/metabolismo , Antibacterianos/farmacologia , Polissacarídeos Bacterianos/metabolismo , Polissacarídeos Bacterianos/farmacologia , Sacarose/farmacologia , Weissella , Fermentação/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Lactose/metabolismo , Testes de Sensibilidade Microbiana , Peso Molecular , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/isolamento & purificação , Temperatura , Weissella/química , Weissella/efeitos dos fármacos , Weissella/metabolismo
17.
Int J Biol Macromol ; 115: 820-828, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29660455

RESUMO

In the present study, an exopolysaccharide (EPS)-producing strain SJ14 isolated from Sichuan paocai was identified as Weissella cibaria, with a typical ropy phenotype. W. cibaria SJ14 possessed good capabilities of acid production, salt tolerance, and nitrite depletion. The crude polysaccharides were obtained from the culture supernatant of strain SJ14 and further fractionated by DEAE-Sepharose Fast Flow ion-exchange and Sephadex G-100 size-exclusion chromatography. Consequently, two acidic EPS fractions (EPS-1 and EPS-3) were obtained with the average molecular weights of 7.12 × 104 and 3.01 × 104 Da, respectively. They were heteropolysaccharides, among which EPS-1 were rich in mannose, and composed of mannose, glucose, galactose, arabinose, xylose, and rhamnose in a molar ratio of 23.79: 4.80: 1.66: 1.00: 0.21: 0.09, whereas EPS-3 consisted of galactose, mannose, glucose, and arabinose in a molar ratio of 7.47: 3.69: 1.00: 0.85 were rich in galactose. Two EPS fractions also exhibited potential antioxidant properties in vitro, showing strong scavenging activities on three kinds of free radicals and reducing power, and the antioxidant activities of EPS-1 were significantly stronger than that of EPS-3.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Verduras/química , Verduras/microbiologia , Weissella/química , Antioxidantes/isolamento & purificação , Fermentação , Peso Molecular , Polissacarídeos Bacterianos/isolamento & purificação , Weissella/metabolismo
18.
Int J Biol Macromol ; 111: 514-525, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29337101

RESUMO

The production, optimization, and characterization of exopolysaccharide (EPS) from Weissella confusa OF126 and the in-vitro probiotic potentials of this strain was investigated. The EPS produced on sucrose modified-MRS broth was characterized. The purified EPS had an average molecular weight of 1.1 × 106 Da. HPLC analysis revealed the presence of glucose monomers, indicating its homopolysaccharide nature. The structural characteristics of the EPS were investigated by FTIR, and NMR spectroscopy. FTIR spectroscopy revealed the presence of hydroxyl, carboxyl, N-acetyl and amine groups. NMR analysis confirmed that the EPS contained α-(1 → 6) linkage and α-(1 → 3) branched linkage. The EPS showed strong in-vitro antioxidant activity. Four significant factors were optimized using Central Composite Design (CCD) and Response Surface Methodology (RSM). The predicted optimum conditions for EPS production were cultivation time (48.50 h), sucrose concentration (24.00 g/L), pH (7.00) and yeast extract (2.50%).The EPS produced was predicted to be 3.10 g/L, while the experimental yield was 3.00 g/L. This strain was found to possess desirable probiotic attributes by its ability to survive at pH 2.0 and in the presence of bile salts (0.50% (w/v)) for 4 h. The results obtained from this study demonstrate W. confusa OF126 as a promising probiotic and the EPS produced can find useful applications in industries.


Assuntos
Antioxidantes/química , Polissacarídeos/química , Probióticos/química , Weissella/química , Antioxidantes/isolamento & purificação , Ácidos e Sais Biliares/química , Glucose/química , Humanos , Polissacarídeos/isolamento & purificação , Probióticos/isolamento & purificação
19.
Int J Biol Macromol ; 107(Pt B): 1765-1772, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29030182

RESUMO

The aim of this study was to monitor the influence of the fermentation conditions on the exopolysaccharides (EPS) biosynthesis. For this, different culture media compositions were tested on an isolated lactic acid bacteria (LAB) strain, identified by 16S rDNA sequence as being Weissella confusa. It was proved that this bacterial strain culture in MRS medium supplemented with 80g/L sucrose and dissolved in UHT milk produced up to 25.2g/L of freeze-dried EPS, in static conditions, after 48h of fermentative process. Using FTIR and NMR analysis, it was demonstrated that the obtained EPS is a dextran. The thermal analysis revealed a dextran structure with high purity while GPC analysis depicted more fractions, which is normal for a biological obtained polymer. A concentration up to 3mg/mL of dextran proved to have no cytotoxic effect on normal human dermal fibroblasts (NHDF). Moreover, at this concentration, dextran breaks up to 70% of the biofilms formed by the Candida albicans SC5314 strain, and has no antimicrobial activity against standard bacterial strains. Due to their characteristics, these EPS are suitable as hydrophilic matrix for controlled release of drugs in pharmaceutical industry.


Assuntos
Dextranos/biossíntese , Weissella/química , Antifúngicos/farmacologia , Varredura Diferencial de Calorimetria , Morte Celular , Sobrevivência Celular , Cromatografia em Gel , Fermentação/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
20.
Sci Rep ; 7: 40040, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-28067304

RESUMO

The occurrence of atopic dermatitis (AD), a chronic inflammatory skin disease, has been increasing steadily in children and adults in recent decades. In this study, we evaluated the ability of the lactic acid bacterium Weissella cibaria WIKIM28 isolated from gatkimchi, a Korean fermented vegetable preparation made from mustard leaves, to suppress the development of AD induced by 2,4-dinitrochlorobenzene in a murine model. Oral administration of W. cibaria WIKIM28 reduced AD-like skin lesions, epidermal thickening, and serum immunoglobulin E levels. Furthermore, the production of type 2 helper T (Th2) cytokines such as interleukin (IL)-4, IL-5, and IL-13 decreased in peripheral lymph node cells. Moreover, the intake of W. cibaria WIKIM28 increased the proportion of CD4+CD25+Foxp3+ regulatory T (Treg) cells in mesenteric lymph nodes (MLNs) and IL-10 levels in polyclonally stimulated MLN cells. In conclusion, the oral administration of W. cibaria WIKIM28 isolated from gatkimchi ameliorated AD-like symptoms by suppressing allergic Th2 responses and inducing Treg responses. These results suggest that W. cibaria WIKIM28 may be applicable as a probiotic for the prevention and amelioration of AD.


Assuntos
Proteínas de Bactérias/administração & dosagem , Células Dendríticas/imunologia , Dermatite Atópica/tratamento farmacológico , Tolerância Imunológica , Fatores Imunológicos/administração & dosagem , Linfócitos T Reguladores/imunologia , Weissella/química , Administração Oral , Animais , Proteínas de Bactérias/isolamento & purificação , Células Dendríticas/efeitos dos fármacos , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/patologia , Modelos Animais de Doenças , Imunoglobulina E/sangue , Fatores Imunológicos/isolamento & purificação , Camundongos Endogâmicos BALB C , Pele/patologia , Linfócitos T Reguladores/efeitos dos fármacos , Resultado do Tratamento
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