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PL
W pracy wykorzystano metodę płaszczyzny odpowiedzi w celu zoptymalizowania biosyntezy 2,3-butanodiolu przez szczep Bacillus licheniformis NCIMB 8059. Oceniono wpływ stężenia ekstraktu drożdżwego oraz jonów CH3COO", Fe2+i Mn2+ na końcową zawartość 2,3-butanodiolu w płynie pohodowlanym. Doświadczenie optymalizacyjne zaprojektowano w oparciu o plan D-optymalny obejmujący 25 wariantów hodowli. Zaobserwowano istotny (p < 0,05) wpływ stężenia ekstraktu drożdżowego oraz jonów CH3COO" i Mn2+na syntezę diolu. Na podstawie analizy statystycznej uzyskano optymalne wartości analizowanych zmiennych, wynoszące (g-dm3): ekstrakt drożdżowy - 4, CH3COONH4- 4, FeS04-7H20 - 0,1 oraz MnS04-H20 - 0,3, które odpowiadały końcowemu stężeniu 2,3-butanodiolu na poziomie 8,9 g-dm-3.
EN
Response surface method was used in this work in order to optimise the biosynthesis of 2,3-butanediol by strain Bacillus licheniformis NCIMB 8059. The effect of yeast extract and concentration of CH3COO", Fe2+and Mn2+ ions was evaluated on the final level of 2,3-butanediol in fermentation broth. The optimisation experiment was planned according to D-optimal design and consisted of 25 runs. Obtained results showed significant influence (p < 0,05) of the yeast extract, CH3COO" and Mn2+ concentration on the studied process. On the basis of statistic analysis, optimal values of analyzed variable were determined as follows (g-dm3): yeast extract - 4, CH3COONH4 - 4, FeS04-7 HzO - 0,1, MnS04-H20 - 0,3, that corresponded to 8,9 g-dm-3 final 2,3-butanediol concentration.
PL
Skonfrontowano wyniki badań dotyczące produkcji enzymów proteolitycznych przez Bacillus licheniformis PCM 1847 z dostępną w literaturze wiedzą i wynikami badań uzyskanymi dla rodzaju Bacillus. Przeprowadzone eksperymenty stanowią etap przygotowawczy do hodowli prowadzonej w bioreaktorze membranowym. W wielu przypadkach zagęszczenie biomasy dzięki zastosowaniu selektywnej membrany przynosi wymierne skutki. Zgodnie z naszą wiedzą, nieznane są przypadki zastosowania bioreaktora membranowego w ciągłej syntezie hydrolaz.
EN
Results received for Bacillus licheniformis PCM 1847 were compared with the data presented in literature. The carried out experiments are the first step to prepare the culture in a membrane bioreactor. Under a high biomass concentration thanks to membrane application a lot of processes run at the high efficiency. To the best of our knowledge the membrane bioreactor has never been applied in the continuous hydro-lases production.
EN
The Bacillus licheniformis ydaP gene encodes for a pyruvate oxidase that catalyses the oxidative decarboxylation of pyruvate to acetate and CO2. The YdaP form of this enzyme was purified about 48.6-folds to homogeneity in three steps. The enzyme was recovered in a soluble form and demonstrated significant activity on pyruvate using 2, 6-dichlorophenolindophenol (DCPIP) as an artificial electron acceptor. HPLC analysis of the YdaP-enzyme catalysed conversion of pyruvate showed acetate as the sole product, confirming the putative identity of pyruvate oxidase. Analysis of the substrate specificity showed that the YdaP enzyme demonstrated preference for short chain oxo acids; however, it was activated by 1% Triton X-100. The YdaP substrate-binding pocket from the YdaP protein differed substantially from the equivalent site in all of the so far characterized pyruvate oxidases, suggesting that the B. licheniformis YdaP might accept different substrates. This could allow more accessibility of large substrates into the active site of this enzyme. The thermostability and pH activity of the YdaP enzyme were determined, with optimums at 50ºC and pH 5.8, respectively. The amino acid residues forming the catalytic cavity were identified as Gln460 to Ala480.
PL
Na podstawie modelu matematycznego opisującego wpływ temperatury na aktywność α-amylazy z Bacillus licheniformis wyznaczono energię aktywacji i dezaktywacji oraz optymalną temperaturę procesu hydrolizy skrobi. Wartości te wynosiły odpowiednio 27,16 ± 6,89 kJ/mol, 143,54 ± 13,31 kJ/mol i 339,76 ± 0,95 K. Założono, że reakcja hydrolizy skrobi katalizowana przez α-amylazę przebiega zgodnie z kinetyką pierwszego rzędu ze względu na stężenie enzymu.
EN
Exptl. data on the temp. relationship of α-amylase from Bacillus licheniformis activity published by Haq et al.¹⁾, were used to calc. the optimal temp., activation energy and deactivation energy of the starch hydrolysis according a resp. math. model of the reaction. The calc. values were 339.76 ± 0.95 K, 27.16 ± 6.89 kJ/mol, 143.54 ± 13.31 kJ/mol, resp.
EN
This study was conducted to determine the effects of Bacillus licheniformis (Bl) and Clostridium butyricum (Cb) and their combinations with yeast culture on in vitro rumen fermentation in a two-way factorial design. Treatments included Bl or Cb at levels of 0, 0.5, 1, 5 and 10 mg and their combination with yeast culture at 0, 18, 27, 36 and 60 mg per 200 mg substrate, respectively. Gas production was recorded after 2, 4, 6, 9, 12, 24, 36, 48 and 72 h incubation. In vitro organic matter digestibility (IVOMD) was estimated by 24 h gas production. Rumen fermentation parameters were determined after 24 h of incubation. Rate constant of gas production was not influenced by Bl or Cb alone, but increased (P<0.05) with inclusion of yeast culture. The IVOMD was influenced (P<0.05) by addition with Bl, Cb or yeast culture, with highest IVOMD observed when Bl or Cb was combined with 60 mg yeast culture. Total volatile fatty acids were affected by Bl and yeast culture (P<0.01), but not by Cb (P>0.05). There were significant interaction effects on pH, acetate to propionate ratio and ammonia-N between yeast culture and Bl or Cb. From the above results, it is indicated that Bl and Cb may be more effective as feed additives when combined with yeast culture than when offered separately.
EN
In this paper the effect of Mo6+, W6+, and Cu2+ ions on kinetics of denitrification and growth of Bacillus licheniformis is presented. The absence lack of Mo6+ and Cu2+ in the growth medium appeared to have no effect on the kinetics of the process. This fact suggests that these ions are not a part of the active centers of denitrification enzymes. Additionaly tungsten (VI) which is competitive to molybdenum (VI) does not inhibit denitrification in concentrations up to 0.1 g/dm3. Molibdenum (VI) starts to inhibit denitrification from 5.0 g/dm3 and copper (II) starting from 0.03 g/dm3.
EN
The influence of ammonia ions and oxygen on the kinetics of denitrification and culture growth of Bacillus licheniformis bacteria is reviewed. It was determined that these microorganisms can utilize both 02 and NO -3 as electron acceptors. They are also able to assimilate NH4+ and NO 3-, and it is conceivable that they also assimilate nitrogen and catalyze nitrification reactions.
EN
The effect of concentration of N,N-Bis(3-aminepropyl)dodecylamine (APDA) used in disinfectants (Lonzabac) on the kinetics of denitrification and desulfurication processes proceeding with the use of Bacillus licheniformis and Desulfotomaculum ruminis bacteria, was studied. The kinetic equation for denitrification in a medium containing the microbiocide tested was derived, the parameters of the process were calculated and the toxicity limits of APDA were established. The latter are of importance when considering means for environment protection against APDA effect on the nitrogen and sulphur cycles.
EN
In this paper we present the results of the study on the effect of n-decane, n-pentane, diesel oil and petrol on the denitrifieation process occuring in the presence of Bacillus licheniformis bacteria. We found that only diesel oil and n-decane could be degraded during denitrifieation catalyzed by bacteria, while petrol and n-pentane inhibited the process.
EN
This paper reports the results of kinetic studies of biodenitrication in which Bacillus licheniformis bacteria are involved, in a medium including either sodium glutamate or aspartic acid as the sole source of carbon. The determined kinetic parameters of the process proved that sodium glutamate is a more effective source of carbon in the process of nitrate reduction, but it is less preferred by bacteria in the process of nitrite reduction.
PL
W pracy opisano immobilizację subtilizyn: z B. subtilis IBTC-3 (typu BPN’), alkalostabilnej z B. alcalophilus BP92 oraz Carlsberg z B. licheniformis na celulozie Whatman oraz szkle porowatym, wykorzystując metodę diizocyjanianową. Lepsze rezultaty dała immobilizacja na szkle porowatym przy użyciu heksametylenodiizocyjanianu. Aktywność proteolityczna immobilizowanych preparatów wynosiła (37,5 - 46,7 mjA/g nośnika przy wydajności 33 - 44%). W pracy określono ponadto właściwości subtilizyny ze szczepu B. subtilis IBTC-3 immobilizowanej na szkle porowatym. Uzyskany preparat enzymatyczny wykazywał optymalną aktywność proteolityczną w pH = 10,7 i temperaturze 60 – 65°C.
EN
In the study the immobilization of subtilisins (from B. subtilis IBTC-3 (type BPN’), high-alkaline from B. alcalophilus BP92, Carlsberg from B. licheniformis) on Whatman cellulose and porous glass with diisocyanate method was carried out. The immobilization on porous glass activated by hexamethylene diisocyanate gave better results than on Whatman cellulose. The proteolytic activity of immobilized preparations was 37,5 - 46,7 mjA/g of support with 33 - 44% yield. The properties of subtilisin from strain B. subtilis IBTC-3 immobilized on porous glass were investigated. The obtained enzymatic preparation showed optimum proteolytic activity at pH = 10,7 and at 60 – 65°C.
EN
We studied the effect of N-oxide of N, N-dimethyl-dodecylamine (DDAO) on catabolic activity of the Bacillus genus bacteria involved in the process of denitrificantion. The laboratory tests have proved that the presence of DDAO in concentrations greater than 75 ppm extends the time of nitrate (V) reduction, while the concentration of the intermediate-formed nitrates (III) is inhibited at the level of 80 mg/dm³. Further increase in DDAO concentration, to 10000 ppm, extends the nitrate (V) reduction time to about 115 hours, while the concentration of nitrates (III), formed in the second stage of the reaction, does nor change and remains at a level of 80-100 mg N-NO₂⁻/dm³. The process of denitrification is accompanied by a decrease in COD (biodegradation), whose concentration after completion of the process is 54% in the samples containing 75 ppm DDAO to 31% in the samples containing 10,000 ppm DDAO. Simultaneously, the concentration of proteins decreases from 70% to 30% in the medium containing DDAO in the concentration of 10,000 ppm.
EN
The influence of didecyldimethylammonium chloride (DDDM) on the processes of denitrification - occurring with a contribution of Bacillus licheniformis bacteria, and desulfurication - with a contribution of Desulfotomaculum ruminis bacteria, was studied. It has been shown in laboratory conditions that the compound tested is not assimilable by the cultures of the above mentioned heterotrophic bacteria and the values of toxic concentrations of DDDM for the studied microorganisms were determined.
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