Wyniki wyszukiwania - Biblioteka Nauki

1

Exopolysaccharides of Rhizobium leguminosarum biovar trifolii harbouring cloned Exo region

100%

Urbanik-Sypniewska T. , Skorupska A. , Derylo M.

Acta Biochimica Polonica

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1992

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tom 39

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nr 2

EN

Rhizobium lexuminosarum bv. trifolii produces an acidic exopolysac- charide (EPS) which plays an important role in the development of nitrogen-fixing nodules. Tn5 mutant of R. trifolii <>3 defective in EPS production (Exo") forms ineffective (Fix-) nodules on red clover. This Exo mutation is complemented by the pARF1368 and pARF25c<>Miiid.s isolated fnuii bank of Rhizobium trifolii TA1, but the complementation is not correlated with restoration of Fix* phenotypt-. Furthermore, these cosmids introduced to wild-type of R. trifolii 24 repress its ability to form nitrogen- -fixing nodules. These results might suggest that bacteria with cosmids carrying the exo region form FPS of altered structure. It has been shown by 'll-n.m.r. that exopolysaccharides produced by R. trifolii 93pARF- 1368 and 93pARF25 contain less non-carbohydrate residues (acetyl, pyruvyl and 3-hydroxybutanoyl) than the wild type KPS. These data suggest that the biological activity of the exopolysaccharide of R. trifolii depends on the contents of the non-carbohydrate substitutions.

2

The region for exopolysaccharide synthesis in Rhizobium leguminosarum biovar trifolii is located on the non-symbiotic plasmid

88%

Skorupska A. , Derylo M. , Golinowski W.

Acta Biochimica Polonica

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1991

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tom 38

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nr 4

3

Bifidogenic and antioxidant activity of exopolysaccharides produced by Lactobacillus rhamnosus E/N cultivated on different carbon sources

75%

Polak-Berecka M. , Wasko A. , Szwajgier D. , Choma A.

Polish Journal of Microbiology

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2013

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tom 62

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nr 2

EN

Lactobacillus rhamnosus E/N is a probiotic bacterium, which synthesizes exopolysaccharides (EPS) with significant bifidogenic and antioxidant activities. The sugar composition of the EPSs produced depended on carbohydrates used as a carbon source in the growth media. Five Bifidobacterium strains were tested in vitro for their ability to utilize all the EPSs studied. The highest bifidogenic activity was revealed by EPSs obtained from Lactobacillus cultures supplemented with Gal, Lac, and Mal as the only carbon source, while significant antioxidant effects were observed in EPSs isolated from growth media enriched with galactose, lactose, and sucrose.

4

Importance of eps genes from Bacillus subtilis in biofilm formation and swarming

63%

Nagorska K. , Ostrowski A. , Hinc K. , Holland I. B. , Obuchowski M.

Journal of Applied Genetics

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2010

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tom 51

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nr 3

EN

Unicellular organisms naturally form multicellular communities, differentiate into specialized cells, and synchronize their behaviour under certain conditions. Swarming, defined as a movement of a large mass of bacteria on solid surfaces, is recognized as a preliminary step in the formation of biofilms. The main aim of this work was to study the role of a group of genes involved in exopolvsaccharide biosynthesis during pellicle formation and swarming in Bacillus subtilis strain 168. To assess the role of particular proteins encoded by the group of epsI-epsO genes that form the eps operon, we constructed a series of insertional mutants. The results obtained showed that mutations in epsJ-epsN, but not in the last gene of the eps operon (epsO), have a severe effect on pellicle formation under all tested conditions. Moreover, the inactivation of 5 out of the 6 genes analysed caused total inhibition of swarming in strain 168 (that does not produce surfactin) on LB medium. Following restoration of the sfp gene (required for production of surfactin, which is essential for swarming of the wild-type bacteria), the sfp⁺ strains defective in eps genes (except epsO) generated significantly different patterns during swarming on synthetic B medium, as compared to the parental strain 168 sfp⁺.

5

Analysis and glycosyl composition of the exopolysaccharide isolated from submerged fermentation of Ganoderma lucidum CG144

63%

Rubel R. , Freire dos Santos L. , Stutz Dalla Santa H. , Porto de Souza Vandenberghe L. , Wojciechowski A. L. , de Carvalho J. C. , Habu S. , Destefanis Vitola F. M. , Augur C. , Soccol C. R.

Acta Societatis Botanicorum Poloniae

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2014

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tom 83

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nr 3

EN

The evaluation of glycosyl composition is an essential step to guide future research designs applied in bioactivity. In the same way, the unexplored potential bioactivity of exopolysaccharide from Ganoderma lucidum is huge. Therefore, this study investigated the glycosyl composition of the exopolysaccharide isolated from submerged fermentation of G. lucidum to serve as guide for future studies on bioactivity. Glycosyl content and composition were evaluated by combined GC/ MS of the TMS derivatives of the monosaccharide methyl glycosides produced from the sample by acidic methanolysis. Glycosyl composition analysis showed that the dominant carbohydrate component in all samples of exopolysaccharide isolated from submerged fermentation of G. lucidum CG 144 was glucose (58.1%), mannose (26.6%) and galactose (12.5%) which can be referred to as heteroglycan. These results suggest that this Ganoderma exopolysaccharide may be a new immunomodulatory agent.

6

Exopolysaccharide from Lactobacillus rhamnosus KL37 inhibits T cell-dependent immune response in mice

63%

Nowak B. , Srottek M. , Ciszek-Lenda M. , Skalkowska A. , Gamian A. , Gorska S. , Marcinkiewicz J.

Archivum Immunologiae et Therapiae Experimentalis

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2020

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tom 68

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nr 3

7

Highly thermostable exopolysaccharide produced by the moderately halophilic bacterium isolated from a man-made young salt lake in Romania

63%

Cojoc R. , Merciu S. , Oancea P. , Pincu E. , Dumitru L. , Enache M.

Polish Journal of Microbiology

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2009

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tom 58

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nr 4

289-294

EN

Halophilic bacterial strains isolated from a man-made salt lake in Romania produce a specific exopolysaccharide. This product is synthesized under both static and stirring conditions, and the yield of this exoploysaccharide depends on the composition of the culture medium. The highest amount of polymer was obtained in the presence of casamino acids and yeast extract, under stirring conditions. This polymer has high thermostability, with a melting point at 207°C. The melting process is associated with the thermal degradation of the compound. This polymer is characterized by maximum absorbtion at 260 nm and fluorescence emission at 530 nm. The FT-IR analysis of the polymer revealed the presence of a saccharide structure and of amine and sulfate groups throughout the sugar backbone.

8

Exopolysaccharides from Xanthomonas citri pv. malvacearum induce resistance in cotton against bacterial blight

63%

Keshkeih R. A. , Abu-Ghorrah M. , Jalloul A.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2019

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tom 100

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nr 2

9

Isolation and characterization of exopolysaccharide-producing Lactobacillus plantarum SKT109 from Tibet Kefir

63%

Wang J. , Zhao X. , Tian Z. , He C. , Yang Y. , Yang Z.

Polish Journal of Food and Nutrition Sciences

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2015

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tom 65

|

nr 4

EN

Lactobacillus plantarum SKT109 was isolated and identified from Tibet Kefir, and the exopolysaccharride (EPS)-producing properties of the strain were evaluated. Growth of strain SKT109 in a semi-defined medium at 37°C increased the viscosity of the medium, corresponding to production of an EPS (58.66 mg/L). The EPS was isolated and purified, and it was shown to consist of fructose and glucose in an approximate molar ratio of 3:1, with an average molecular weight of 2.1x106 Da. The aqueous solution of EPS at 1% (w/v) exhibited shear thinning behavior. Microstructural studies of the EPS demonstrated a highly compact structure with a smooth surface, facilitating formation of film by the polymer; the EPS was composed of many different sizes of spherical lumps with tendency to form molecular aggregates. Studies on the milk fermentation characteristics of L. plantarum SKT109 showed that the strain survived well in fermented milk with counts about 8.0 log cfu/g during 21 days of storage at 4°C. The use of the EPS-producing strain improved the rheology of the fermented milk without causing post-acidification during storage. Particularly, L. plantarum SKT109 improved the fermented milk flavor by increasing the concentration of characteristic flavor compounds and eliminating those with disgusting flavors. The results of the present study indicated that EPS-producing L. plantarum SKT109 could serve as a promising candidate for further exploitation in fermented foods.

10

Role of Rhizobium surface components in biological nitrogen fixation

63%

Lorkiewicz Z.

Bulletin of the Polish Academy of Sciences. Biological Sciences

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1994

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tom 42

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nr 2

11

Ocena wpływu kultury starterowej Weissella cibaria ZFJ3 na właściwości lepkie zakwasów gryczanych i jakość pieczywa bezglutenowego

51%

Acta Agrophysica

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2017

|

tom 24

|

nr 4

PL

Celem pracy była ocena możliwości zastosowania bakteryjnej kultury starterowej, zawierającej szczep Weissella cibaria ZFJ3 syntetyzujący egzopolisacharydy, do poprawy jakości bezglutenowego pieczywa gryczanego. Porównano właściwości lepkie oraz fizykochemiczne zakwasów gryczanych uzyskanych z tym szczepem z zakwasami ze szczepem Pediococcus pentosaceus ZFG2 (wchodzącym w skład komercyjnej kultury starterowej do chleba gryczanego) oraz zakwasem spontanicznie fermentującym (bez kultur starterowych). Stwierdzono, że zakwas otrzymany z W. cibaria ZFJ3 charakteryzował się najwyższą lepkością spośród badanych. Pieczywo otrzymane z tym szczepem oceniono jako atrakcyjne sensorycznie, a jego parametry fizykochemiczne jako lepsze lub zbliżone do pieczywa stanowiącego próbę kontrolną.

EN

The aim of the study was to evaluate the efficiency of application of a bacterial starter culture, containing the strain Weissella cibaria ZFJ3 producing exopolysaccharides, to improve the quality of gluten-free buckwheat. The viscosity and physicochemical properties of buckwheat sourdough obtained with this strain, with lees of Pediococcus pentosaceus ZFG2 (included in the commercial starter culture) and spontaneous sourdough (without starter culture), were compared with the highest viscosity obtained from W. cibaria ZFJ3. The bread obtained with this strain was evaluated as having attractive sensory values, and its physicochemical parameters as better or similar to the control bread.

12

Wpływ wybranych warunków środowiskowych na biosyntezę egzopolimerycznych składników biofilmu przez bakterie Bacillus cereus

51%

Sobolczyk J. , Rodziewicz A. , Baranowska K.

Acta Scientiarum Polonorum. Biotechnologia

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2009

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tom 08

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nr 1

PL

W pracy badano tworzenie egzopolimerycznych składników biofilmu (EPS) przez trzy szczepy bakterii z gatunku Bacillus cereus. Egzopolimery wydzielane przez poszczególne szczepy różniły się jakościowo i ilościowo. Wzajemne proporcje polisacharydów i białek EPS zależały w najwyższym stopniu od dostępności źródła węgla w środowisku oraz od obecności dodatkowych powierzchni przylegania bakterii. Biologiczne powierzchnie w postaci piór drobiowych stymulowały produkcję polisacharydów przez bakterie, natomiast abiotyczne w postaci płytek szklanych indukowały zwiększone wydzielanie białek. W białkowej części biofilmu elektroforetycznie wykazano obecność dodatkowych frakcji białkowych, nieobecnych w warunkach kontrolnych. Tworzenie egzopolimerycznej macierzy przez bakterie uwarunkowane jest genetycznie, ale również w wysokim stopniu zależało od dostępności składników odżywczych, a także od czasu trwania hodowli.

EN

In this research we investigated releasing of biofilm exopolymeric substance by three strains of Bacillus cereus species. We observed the difference in quality and quantity of produced exopolymers. The proportion between polysaccharides and proteins in EPS depended on the availability of carbon source in the culture environment and the presence of additional adhesion surface. Biological surfaces like poultry feathers stimulated releasing of polysaccharides by tested bacteria, however abiotic surfaces like glass plates induced protein's releasing. In the proteins of biofilm by SDS polyacrylamide gel electrophoresis revealed the presence of additional fraction of proteins absent in control conditions. Production of exopolymeric matrix by bacteria is regulated by genetic mechanisms but it also highly depends on nutrient level and cultivating time.

13

Selekcja bakterii z rodzaju Lactobacillus wydajnych w syntezie egzopolisacharydów

51%

Oleksy M. , Klewicka E.

Żywność Nauka Technologia Jakość

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2017

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tom 24

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nr 2

PL

Egzopolisacharydy (EPS) bakterii z rodzaju Lactobacillus charakteryzują się korzystnymi właściwościami prozdrowotnymi, dzięki którym mogą być stosowane jako funkcjonalne składniki żywności. Ich wykorzystanie na skalę przemysłową jest jednak utrudnione ze względu na wysoki koszt oraz niską wydajność produkcji. Odpowiedni dobór szczepów wydajnych w syntezie EPS może znacznie zwiększyć szansę ich wykorzystania w technologii żywności. Celem pracy była selekcja szczepów bakterii z rodzaju Lactobacillus zdolnych do wydajnej syntezy egzopolisacharydów zarówno w formie śluzu, jak i otoczek polisacharydowych. Na podstawie przeprowadzonych analiz makro- i mikroskopowych spośród 58 szczepów wytypowano trzy szczepy z gatunku Lactobacillus rhamnosus (ŁOCK 0943, ŁOCK 0935 oraz OM1) o najkorzystniejszych cechach wpływających na właściwości reologiczne podłoża hodowlanego. W pracy wykazano, że szczepy te mogą stanowić wydajne narzędzie w produkcji bakteryjnych egzpolisacharydów. Badane bakterie syntetyzują EPS w ilości 68 ÷ 137 mg/l w zależności od rodzaju źródła węgla. Zatem skład podłoża hodowlanego jest jednym z czynników determinujących wydajność syntezy EPS przez bakterie z rodzaju Lactobacillus.

EN

Exopolysaccharides (EPS) produced by bacteria of the Lactobacillus genus are characterized by beneficial health-promoting properties owing to which EPS can be used as functional food ingredients. However, their utilization on an industrial scale is made difficult by high costs of their production and low productivity. A way to increase the prospect of utilizing EPS in food technology is to properly select strains that are efficient in the synthesis thereof. The objective of the research study was to select Lactobacillus strains capable of efficiently synthesizing EPS both in the form of slime and capsular polysaccharides. Based on the macro- and microscopic analyses, three Lactobacillus rhamnosus strains (LOCK 0943, ŁOCK 0935, and OM-1) were selected from among 58 lactobacilli strains; they had the most beneficial properties to impact the rheology of the culture medium. The study showed that those strains could be an effective tool in the production of bacterial exopolysaccharides. The tested bacteria synthesized 68 to 137 mg/L of EPS depending on the type of carbon source. Thus, the composition of the culture medium is one of the factors to determine the efficiency of EPS synthesis by Lactobacillus bacteria.

14

Role of the exopolysaccharides of Nostoc linckia (Cyanophyta) in accumulation of metal ions from the environment

51%

Shnyukova E. I.

Acta Physiologiae Plantarum

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2007

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tom 29

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nr 1 Suppl.

15

Chitin-glucan complex production by Schizophyllum commune submerged cultivation

51%

Smirnou D. , Krcmar M. , Prochazkova E.

Polish Journal of Microbiology

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2011

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tom 60

|

nr 3

EN

Chitin-glucan complex is a fungal origin copolymer that finds application in medicine and cosmetics. Traditionally, the mycelium of Micromycetes is considered as an industrial chitin-glucan complex source. Basidiomycete Schizophyllum commune submerged cultivation for chitin-glucan complex production was studied. In different S.commune strains chitin-glucan complex composed 15.2 ± 0.4 to 30.2 ± 0.2% of mycelium dry weight. Optimized conditions for chitin-glucan complex production (nutrient medium composition in g/l: sucrose – 35, yeast extract – 4, Na₂HPO₄ *12H₂O – 2.5, MgSO₄ *7 H₂O – 0.5; medium initial pH 6.5; aeration intensity 2 l of air per 1 l of medium; 144 hours of cultivation) resulted in 3.5 ± 0.3 g/l complex yield. Redirection of fungal metabolism from exopolysaccharide synthesis to chitin-glucan complex accumulation was achieved most efficiently by aeration intensity increase. Chitin-glucan complex from S.commune had the structure of microfibers with diameter 1–2 µm, had water-swelling capacity of 18 g/g, and was composed of 16.63% chitin and 83.37% glucan with a degree of chitin deacetylation of 26.9 %. S.commune submerged cultivation is a potent alternative to Micromycetes for industrial-scale chitin-glucan complex production.

16

Lactobacillus rhamnosus exopolysaccharide ameliorates arthritis induced by the systemic injection of collagen and lipopolysaccharide in DBA/1 mice

51%

Nowak B. , Ciszek-Lenda M. , Srottek M. , Gamian A. , Kontny E. , Gorska-Fraczek S. , Marcinkiewicz J.

Archivum Immunologiae et Therapiae Experimentalis

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2012

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tom 60

|

nr 3

17

Rhizobium leguminosarum Biovar trifolii mutants altered in surface structures that are defective in nodulation or nitrogen fixation

51%

Lorkiewicz Z. , Derylo M. , Russa R. , Skorupska A. , Urbanik-Sypniewska T.

Acta Microbiologica Polonica

|

1993

|

tom 42

|

nr 3-4

18

Molecular characterization and symbiotic importance of prsD gene of Rhizobium leguminosarum bv.trifolii TA1

51%

Mazur A. , Wielbo J. , Krol J. , Kopcinska J. , Lotocka B. , Golinowski W. , Skorupska A.

Acta Biochimica Polonica

|

1998

|

tom 45

|

nr 4

EN

The prsD, prsE and orf3 genes of Rhizobium leguminosarum bv. trifolii strain TA1 encode the proteins which are significantly related to the family of bacterial ABC transporters type I secretion systems. The prsD:Kmr mutant of strain TA1 induced non-nitrogen-fixing nodules on Trifolium pratense. Microscopic analysis of the nodules induced by prsD mutant did not reveal major abberations in the bacteroid appearance. The exopolysaccharide of prsD mutant was produced in increased amount and its level of polymerization was changed. SDS/PAGE of the proteins from the culture supernatants showed a lack of the 47-kDa protein in the culture of prsD mutant. Thus, PrsD may play a role in the export of this protein.

19

Homology of genes for exopolysaccharide synthesis in Rhizobium leguminosarum and effect of cloned exo genes on nodule formation

51%

Skorupska A. , Derylo M.

|

1993

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tom 40

|

nr 4

EN

A 5.4 kb BamHl fragment of R. leguminosarum bv. trifolii TA1 was found to carry genes involved in exopolysaccharide synthesis (caro genes). This fragment was strongly hybridized to the total DNA from R. I. bv. viciae and bv. phaseoli digested with EcoRI. No homology was found with total DNA of R. meliloti and Rhizobium sp. NGR 234. The exo genes from R. I. bv. trifoliiTAl conjugally introduced into R. I. bv. viciae 1302 considerably affected the symbiosis: the nodules induced on vetch were abortive and did not fix nitrogen. On the other hand, Phaseolus beans infected with R. I. bv. phaseoli harbouring R. I. bv. trifolii exo genes formed the nitrogen-fixing nodules. It can be concluded that additional copies of exo genes introduced into wild type Rhizobium leguminosarum strains can disturb the synthesis of acidic exo- polysaccharides and affect symbiosis of the plants forming indeterminate nodules, but do not affect symbiosis of the plants forming the determinate nodules.

20

Rola egzopolisacharydów mikrobiologicznych w technologii żywności

38%

Myszka K. , Czaczyk K.

Żywność Nauka Technologia Jakość

|

2004

|

tom 11

|

nr 4

18-29

PL

Poznanie wszystkich czynników determinujących biosyntezę egzopolisacharydów drobnoustrojowych jest bardzo istotne. Wykorzystując bowiem odpowiednio skomponowane podłoże hodowlane, pod względem źródła węgla, energii, mikroelementów czy pH, możliwe jest otrzymanie materiału o funkcjonalnym charakterze. Wydzielane na zewnątrz komórki polisacharydy (głównie w formie śluzu) mają duże znaczenie w technologii żywności. Węglowodany pochodzenia mikrobiologicznego, takie jak: ksantan, kurdlan, pululan czy alginian, charakteryzują się wieloma cechami, których nie mają polimery roślinne. Dodatek tych związków do produktów spożywczych ma na celu utrzymanie pożądanej konsystencji, zwiększenie lepkości, zmniejszenie strat wody w czasie obróbki i przechowywania oraz produkcję żywności niskokalorycznej. Obecnie substancje te stosowane są również do produkcji wytrzymałych i jadalnych powłok, które zabezpieczają produkt przed zepsuciem. W niniejszej pracy przedstawiono także aspekt higieniczny syntezy egzopolisacharydów mikrobiologicznych, jako potencjalnego źródła skażenia gotowych wyrobów przeznaczonych do obrotu handlowego. Substancje te uczestniczą w procesach tworzenia się stabilnego mechanicznie biofilmu, co utrudnia utrzymanie czystości w zakładach produkcyjnych. Mikroorganizmy wytwarzają pozakomórkowo ściśle zdefiniowane pod względem struktury polisacharydy, które mogą być wskaźnikami występujących w danym środowisku zanieczyszczeń. Ta właściwość ma kluczowe znaczenie w poszukiwaniach efektywnych metod higienizacyjnych różnych powierzchni użytkowych.

EN

It is very important to identify all the agents determining the exo-polysaccharides synthesis. Using a culture medium that is adequately composed as regards carbon, energy, microelements, or pH, it is possible to obtain a desirable and functional biomaterial. Polysaccharides that are secreted outside the cell (usually in the form of mucus) are very important for the food technology. Microbiological carbohydrates such as: xanthan, curdlan, pullulan, and alginate show many specific characteristics, which other plant polymers do not have at all. The function of these compounds added to food products is to keep a desired consistency level, to increase viscosity, to reduce water losses during processing and storage, and to manufacture low calories food products. Presently, they are also applied to manufacture durable and edible covers protecting food products against spoiling. In this paper, there are presented some hygienic aspects of synthesis of microbiological exo-polysaccharides that constitute a potential risk of contaminating final food products to be marketed. These substances take part in the process of forming a mechanically stable biofilm that makes it difficult to keep a required cleanness level within the food manufacturing factories. Owing to the fact that micro-organisms extra-cellularly produce polysaccharides with exactly defined structures, and they can be indicators of contaminants probably occurring in a given environment. This property may be of essential importance if seeking effective methods for higienisation of various application surfaces.