Nejvíce citovaný článek - PubMed ID 8262448
Monensin has no effect on growth and metabolism of Megasphaera elsdenii
Bifidobacteria (246 strains in total) were isolated from rectal samples of infants and adult humans and animals, and from intestinal samples of calves. Twenty-five strains grew well on mucin: 20 from infants, two from adults, and three from goatlings. Poor or no growth on mucin was observed in 156 bifidobacterial strains of animal origin. The difference between human and animal isolates in ability to grow on mucin was significant at p < 0.001. Nine human strains with the best growth on mucin were identified as Bifidobacterium bifidum. These strains produced extracellular, membrane-bound, and intracellular mucinases with activities of 0.11, 0.53, and 0.09 μmol/min of reducing sugars per milligram of protein, respectively. Membrane-bound mucinases were active between pH 5 and 10. The optimum pH of extracellular mucinases was 6-7. Fermentation patterns in cultures grown on mucin and glucose differed. On mucin, the acetate-to-lactate ratio was higher than in cultures grown on glucose (p = 0.012). We showed that the bifidobacteria belong to the mucin-fermenting bacteria in humans, but their significance in mucin degradation in animals seems to be limited.
- MeSH
- Bifidobacterium enzymologie genetika izolace a purifikace metabolismus MeSH
- dospělí MeSH
- fermentace MeSH
- glukosa metabolismus MeSH
- kojenec MeSH
- koncentrace vodíkových iontů MeSH
- kozy MeSH
- lidé MeSH
- muciny metabolismus MeSH
- polysacharid-lyasy chemie metabolismus MeSH
- skot MeSH
- stabilita enzymů MeSH
- teplota MeSH
- tlusté střevo mikrobiologie MeSH
- zvířata MeSH
- Check Tag
- dospělí MeSH
- kojenec MeSH
- lidé MeSH
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Názvy látek
- glukosa MeSH
- hyaluronate lyase MeSH Prohlížeč
- muciny MeSH
- polysacharid-lyasy MeSH
The effect of daily supplementation of nisin (2 mg/L), monensin (5.88 mg/L) and nisin and monensin (2 + 5.88 mg/L) on ovine ruminal ciliates and bacteria was investigated using the artificial rumen RUSITEC. Major groups in RUSITEC were Entodinium spp. and Dasytricha ruminantium. The supplementation of nisin significantly increased the population of both major ciliate groups. The supplementation of monensin significantly decreased the population of both groups. The combined effect of nisin and monensin was similar to the effect of monensin. Monensin had strong antiprotozoic effects in contrast to the stimulatory effects of nisin. D. ruminantium followed by Entodinium spp. appeared more resistant to tested compounds than other rumen ciliates. Tested additives did not significantly influence the presence and growth of amylolytic streptococci and enterococci but nisin showed a tendency to decreasing the concentration of Escherichia coli and lactobacilli.
- MeSH
- bachor mikrobiologie parazitologie MeSH
- Bacteria účinky léků MeSH
- dezinficiencia aplikace a dávkování MeSH
- dieta metody MeSH
- Eukaryota účinky léků MeSH
- monensin aplikace a dávkování MeSH
- nisin aplikace a dávkování MeSH
- ovce MeSH
- teoretické modely MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- dezinficiencia MeSH
- monensin MeSH
- nisin MeSH
The presence of phytase activity was demonstrated in 26 strains of rabbit cecal bacteria. In 25 strains a low phytase activity, 0.10-0.62 micromol phosphate released per min per mg protein, was found. High activity (2.61 micromol/min per mg protein) was found in the strain PP2 identified as Enterococcus hirae. Phytase activity was cell-associated, being higher in the cell extract than in the cell walls. Extracellular phytase activity and cell-associated phosphatase activity were not detected. Phytase activity was optimal around pH 5.0, which is below the physiological cecal pH range. The K (m) determined using the Lineweaver-Burk plot was 0.19 micromol/mL. Cations Fe(3+), Cu(2+) and Zn(2+) at 0.5 mmol/L decreased phytase activity in sonicated cells of E. hirae by 99.4, 90.7 and 96.5 %, respectively. In contrast, Mg(2+) increased activity by 11.0 %. Characteristics of E. hirae phytase (pH optimum, K (m), cation sensitivity) were similar to those of other bacterial phytases reported in the literature. Other bacteria with a high phytase activity may be present in the rabbit cecum but remain to be identified.
- MeSH
- 6-fytasa chemie metabolismus MeSH
- Bacteria chemie enzymologie izolace a purifikace MeSH
- bakteriální proteiny chemie metabolismus MeSH
- cékum mikrobiologie MeSH
- Enterococcus chemie genetika izolace a purifikace MeSH
- kinetika MeSH
- králíci MeSH
- stabilita enzymů MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- 6-fytasa MeSH
- bakteriální proteiny MeSH
Five 11-week-old rabbits, fed a commercial granulated feed, were slaughtered and cecal starch-degrading bacteria enumerated; total concentration of cultivable bacteria utilizing starch averaged 5.5 x 10(10) CFU/g. The activity and cellular localization of amylases was determined in 9 bacteria identified as Actinomyces israeli (strains AA2 and AD4), Bacteroides spp. (strain AA3), Dichelobacter nodosus (strain AA4), Mitsuokella multiacidus (strain AA6), Eubacterium spp. (strains AA7 and AB2), Clostridium spp. (strains AD1 and AA5). Four strains (AA3, AA4, AA5, AD4) produced extracellular amylases with an activity of 26-35 micromol of reducing sugars per h per mg of protein; in five strains (AA2, AA6, AA7, AB2, AD1) amylases were membrane-bound with an activity of 14-18 micromol of reducing sugars per h per mg of protein. All strains exhibited a low intracellular amylolytic activity. The pH optimum of amylases was 6.8-7.0. In strains producing extracellular amylases a substantial loss of viscosity was observed during incubations of cultivation supernatant with starch, similar to viscosity reduction in starch solutions treated with alpha-amylase; this indicates an endo-type (random cleavage) of extracellular amylase reaction in the bacteria under study. No strain possessed glucoamylase activity.
- MeSH
- amylasy analýza metabolismus MeSH
- Bacteria enzymologie izolace a purifikace MeSH
- cékum metabolismus mikrobiologie MeSH
- hybridizace in situ fluorescenční MeSH
- koncentrace vodíkových iontů MeSH
- králíci MeSH
- škrob metabolismus MeSH
- trávení fyziologie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- amylasy MeSH
- škrob MeSH
Two strains of Bifidobacterium globosum were isolated from caecal contents of rabbits in a search for potential probiotics. Both strains fermented glucose, galactose, pentoses, maltose, raffinose and starch. Common coccidiostats (monensin, salinomycin) and antimicrobial growth promotors (avoparcin, bacitracin, nitrovin, virginiamycin) supplied at 10 mg/L inhibited their growth in cultures with glucose. Fermentation parameters of bifidobacteria on glucose and starch differed. More formate and ethanol and less lactate were produced during growth on glucose than during growth on starch. When growing on starch, the two strains of bifidobacteria produced 1 mol lactate per 5.6 and 5.7 mol acetate, respectively. Corresponding values during growth on glucose were 17.3 and 8.4 mol of acetate per mol of lactate. Starch-grown cells accumulated more saccharides than cells grown on glucose (1.48 vs. 0.41 and 3.12 vs. 1.18 mmol glucose units per 1 g of dry matter, respectively).
- MeSH
- Bifidobacterium izolace a purifikace metabolismus MeSH
- cékum mikrobiologie MeSH
- fermentace MeSH
- glukosa metabolismus MeSH
- králíci MeSH
- škrob metabolismus MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- glukosa MeSH
- škrob MeSH
The growth of Enterococcus faecium strains CCM 4231 and EF 26, and Staphylococcus gallinarum SG 31 was inhibited by salinomycin and lasalocid at concentrations of 25 and 50 mg/L. Staphylococcus gallinarum was more sensitive to the additives used than were enterococci. Maximum inhibition (90%) was measured after the growth with the SG 31 strain in the presence of both ionophores. Growth of organisms was more inhibited by salinomycin at 25 mg/L (67.5%) than at 50 mg/L (63%). The inhibitory effect in enterococcal strains reached after the addition of salinomycin and lasalocid (on average) 63 and 58%, respectively. The CCM 4231 strain was more inhibited by salinomycin as well as by lasalocid than was the EF 26 strain.
