| 71. |
- Panagiotou, Gianni, et al.
(författare)
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Induction, purification, and characterization of two extracellular alpha-L-arabinofuranosidases from Fusarium oxysporum
- 2003
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Ingår i: Canadian journal of microbiology (Print). - 0008-4166 .- 1480-3275. ; 49:10, s. 639-644
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Tidskriftsartikel (refereegranskat)abstract
- In the presence of L-arabinose as sole carbon source, Fusarium oxysporum produces two α-L-arabinofuranosidases (ABFs) named ABF1 and ABF2, with molecular masses of 200 and 180 kDa, respectively. The two F. oxysporum proteins have been purified to homogeneity. The purified enzymes are composed of three equal subunits and are neutral proteins with pIs of 6.0 and 7.3 for ABF1 and ABF2, respectively. With p-nitrophenyl α-L-arabinofuranoside (pNPA) as the substrate, ABF1 and ABF2 exhibited Km values of 0.39 and 0.28 mmol·L–1, respectively, and Vmax values of 1.6 and 4.6 µmol·min–1·(mg of protein)–1, respectively, and displayed optimal activity at pH 6.0 and 50–60 °C. ABFs released arabinose only from sugar beet arabinan and not from wheat soluble and insoluble arabinoxylans. The enzymes were not active on substrates containing ferulic acid ester linked to C-5 and C-2 linkages of pNPA showing that phenolic substituents of pNPA sterically hindered the action of ABFs.Key words: α-L-arabinofuranosidase, enzyme purification, enzyme induction.
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| 72. |
- Panagiotou, Gianni, et al.
(författare)
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Production of cellulolytic and xylanolytic enzymes by Fusarium oxysporum grown on corn stover in solid state fermentation
- 2003
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Ingår i: Industrial crops and products (Print). - 0926-6690 .- 1872-633X. ; 18:1, s. 35-47
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Tidskriftsartikel (refereegranskat)abstract
- Corn stover is an abundant, potential fermentation substrate. Production of cellulolytic and xylanolytic enzymes by the mesophilic fungus Fusarium oxysporum under solid state culture (SSC) on corn stover was enhanced by optimization of the type of nitrogen source, initial moisture level, growth temperature and initial pH of the culture medium. Under these conditions, yields as high as 304, 4.1, 0.140, 1840 and 0.041 U/g of carbon source of endoglucanase, cellobiohydrolase, β-glucosidase, xylanase and β-xylosidase, respectively, were obtained. SCC in a laboratory horizontal bioreactor using the optimized medium allowed the large scale production of the multienzymic system in similar yields. Chromogenic (fluorogenic) 4-methylumbelliferyl β-glycosides of cellobiose and xylobiose were used to characterize the major activities of the multienzyme component, after separation by isoelectric focusing (IEF) electrophoresis. The zymograms indicated one major cellulase and four xylanase activities exhibiting pI values 5 and 5, 6, 7.3, 8.3, respectively.
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| 73. |
- Papaparaskevas, Dimitris, et al.
(författare)
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Optimizing production of extracellular lipase from Rhodotorula glutinis
- 1992
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Ingår i: Biotechnology letters. - 0141-5492 .- 1573-6776. ; 14:5, s. 397-402
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Tidskriftsartikel (refereegranskat)abstract
- Production of extracellular lipase byRhodotorula glutinis was substantially enhanced when the type and concentration of carbon and nitrogen source, the initial pH of culture medium and the growth temperature were consecutively optimized. Lipase activity as high as 30.4 U/ml of culture medium was obtained at optimum conditions, comparing favourably with most of the activities reported for other lipase hyperproducing microorganisms. The enzyme was optimally active at pH 7.5 and 35°C and had, at optimum pH, half-lives of 45 and 11.8 min at 45 and 55°C respectively. The high activity and kinetic characteristics of the enzyme make this process worthy of further investigation.
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| 74. |
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| 75. |
- Puchart, Vladimı́r, et al.
(författare)
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Production of xylanases, mannanases, and pectinases by the thermophilic fungus Thermomyces lanuginosus
- 1999
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Ingår i: Enzyme and microbial technology. - 0141-0229 .- 1879-0909. ; 24:5-6, s. 355-361
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Tidskriftsartikel (refereegranskat)abstract
- A group of 17 strains of the thermophilic fungus Thermomyces lanuginosus was examined for the production of xylanases, β-mannanases, arabinanases, and pectinases. All strains were found to be xylanolytic, and several were proven to be outstanding producers of microbial xylanase on glucuronoxylan and corn cobs. The strains hyperproducing xylanase secreted low amounts of xylan-debranching enzymes and did not produce β-mannan and arabinan-degrading enzyme systems. Only the strains showing lower xylanase production exhibited a higher degree of xylan utilization and also the ability to produce a mannanolytic enzyme system. One of the mannanolytic strains was found to be capable of producing arabinan-degrading enzymes. This strain also showed the best production of pectinolytic enzymes during growth on citrus pectin or sugar beet pulp. Some of the strains have good potential for use as sources of important industrial enzymes of high thermal stability.
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| 76. |
- Rao, Meena P, et al.
(författare)
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Blood Pressure Control and Risk of Stroke or Systemic Embolism in Patients With Atrial Fibrillation : Results From the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) Trial
- 2015
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Ingår i: Journal of the American Heart Association. - 2047-9980 .- 2047-9980. ; 4:12
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Patients with atrial fibrillation (AF) and hypertension are at high risk for stroke. Previous studies have shown elevated risk of stroke in patients with AF who have a history of hypertension (regardless of blood pressure [BP] control) and in patients with elevated BP. We assessed the association of hypertension and BP control on clinical outcomes.METHODS AND RESULTS: In ARISTOTLE (n=18 201), BP was evaluated as history of hypertension requiring treatment and elevated BP (systolic ≥140 and/or diastolic ≥90 mm Hg) at study entry and any point during the trial. Hazard ratios (HRs) were derived from Cox proportional hazards models including BP as a time-dependent covariate. A total of 15 916 (87.5%) patients had a history of hypertension requiring treatment. In patients with elevated BP measurement at any point during the trial, the rate of stroke or systemic embolism was significantly higher (HR, 1.53; 95% confidence interval [CI], 1.25-1.86), as was hemorrhagic stroke (HR 1.85; 95% CI, 1.26-2.72) and ischemic stroke (HR, 1.50; 95% CI, 1.18-1.90). Rates of major bleeding were lower in patients with a history of hypertension (HR, 0.80; 95% CI, 0.66-0.98) and nonsignificantly lower in patients with elevated BP at study entry (HR, 0.89; 95% CI, 0.77-1.03). The benefit of apixaban versus warfarin on preventing stroke or systemic embolism was consistent among patients with and without a history of hypertension (P interaction=0.27), BP control at baseline (P interaction=0.43), and BP control during the trial (P interaction=0.97).CONCLUSIONS: High BP measurement at any point during the trial was independently associated with a substantially higher risk of stroke or systemic embolism. These results strongly support efforts to treat elevated BP as an important strategy to optimally lower risk of stroke in patients with AF.CLINICAL TRIAL REGISTRATION: URL: https://ClinicalTrials.gov/. Unique identifier: NCT00412984.
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| 77. |
- Seferovic, Petar M., et al.
(författare)
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Clinical practice update on heart failure 2019: pharmacotherapy, procedures, devices and patient management. An expert consensus meeting report of the Heart Failure Association of the European Society of Cardiology
- 2019
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Ingår i: European Journal of Heart Failure. - : WILEY. - 1388-9842 .- 1879-0844. ; 21:10, s. 1169-1186
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Tidskriftsartikel (refereegranskat)abstract
- The European Society of Cardiology (ESC) has published a series of guidelines on heart failure (HF) over the last 25 years, most recently in 2016. Given the amount of new information that has become available since then, the Heart Failure Association (HFA) of the ESC recognized the need to review and summarise recent developments in a consensus document. Here we report from the HFA workshop that was held in January 2019 in Frankfurt, Germany. This expert consensus report is neither a guideline update nor a position statement, but rather a summary and consensus view in the form of consensus recommendations. The report describes how these guidance statements are supported by evidence, it makes some practical comments, and it highlights new research areas and how progress might change the clinical management of HF. We have avoided re-interpretation of information already considered in the 2016 ESC/HFA guidelines. Specific new recommendations have been made based on the evidence from major trials published since 2016, including sodium-glucose co-transporter 2 inhibitors in type 2 diabetes mellitus, MitraClip for functional mitral regurgitation, atrial fibrillation ablation in HF, tafamidis in cardiac transthyretin amyloidosis, rivaroxaban in HF, implantable cardioverter-defibrillators in non-ischaemic HF, and telemedicine for HF. In addition, new trial evidence from smaller trials and updated meta-analyses have given us the chance to provide refined recommendations in selected other areas. Further, new trial evidence is due in many of these areas and others over the next 2 years, in time for the planned 2021 ESC guidelines on the diagnosis and treatment of acute and chronic heart failure.
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| 78. |
- Smolka, Jochen, et al.
(författare)
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Night sky orientation with diurnal and nocturnal eyes: dim-light adaptations are critical when the moon is out of sight
- 2016
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Ingår i: Animal Behaviour. - : Elsevier BV. - 1095-8282 .- 0003-3472. ; 111, s. 127-146
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Tidskriftsartikel (refereegranskat)abstract
- The visual systems of many animals feature energetically costly specializations to enable them to function in dim light. It is often unclear, however, how large the behavioural benefit of these specializations is, because a direct comparison in a behaviourally relevant task between closely related day- and night-active species is not usually possible. Here we compared the orientation performance of diurnal and nocturnal species of dung beetles, Scarabaeus (Kheper) lamarcki and Scarabaeus satyrus, respectively, attempting to roll dung balls along straight paths both during the day and at night. Using video tracking, we quantified the straightness of paths and the repeatability of roll bearings as beetles exited a flat arena in their natural habitat or under controlled conditions indoors. Both species oriented equally well when either the moon or an artificial point light source was available, but when the view of the moon was blocked and only wide-field cues such as the lunar polarization pattern or the stars were available for orientation, nocturnal beetles were oriented substantially better. We found no evidence that ball-rolling speed changed with light level, which suggests little or no temporal summation in the visual system. Finally, we found that both diurnal and nocturnal beetles tended to choose bearings that led them towards a bright light source, but away from a dim one. Our results show that even diurnal insects, at least those with superposition eyes, could orient by the light of the moon, but that dim-light adaptations are needed for precise orientation when the moon is not visible.
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| 79. |
- Topakas, Evangelos, et al.
(författare)
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Production and partial characterisation of feruloyl esterase by Sporotrichum thermophile in solid-state fermentation
- 2003
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Ingår i: Process Biochemistry. - 1359-5113 .- 1873-3298. ; 38:11, s. 1539-1543
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Tidskriftsartikel (refereegranskat)abstract
- A number of factors affecting production of feruloyl esterase an enzyme that hydrolyse ester linkages of ferulic acid (FA) in plant cell walls, by the thermophylic fungus Sporotrichum thermophile under solid state fermentation (SSF) were investigated. Initial moisture content and type of carbon source were consecutively optimised. SSF in a laboratory horizontal bioreactor using the optimised medium allowed the production of 156 mU g−1 of carbon source, which compared favourably with those reported for the other micro-organisms. Optimal esterase activity was observed at pH 8 and 60 °C. The activity of the esterase was measured on an insoluble feruloylated hemicellulose substrate (de-starched wheat bran (DSWB)). De-esterification of wheat straw yielded loss of feruloyl esterase production even though the supplementation of free FA comparable to the alkali-extractable levels of FA found in wheat straw. Chromogenic (fluorogenic) 4-methylumbelliferyl ferulate was used to characterise the multienzyme component, after separation by isoelectric focusing and native PAGE electrophoresis. The zymograms indicated one major esterase activity exhibiting pI and molecular mass values 5 and 27 kDa, respectively.
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| 80. |
- Topakas, Evangelos, et al.
(författare)
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Production and partial characterization of xylanase from Sporotrichum thermophile under solid-state fermentation
- 2003
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Ingår i: World Journal of Microbiology & Biotechnology. - 0959-3993 .- 1573-0972. ; 19:2, s. 195-198
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Tidskriftsartikel (refereegranskat)abstract
- A number of factors affecting production of xylanase, by the thermophilic fungus Sporotrichum thermophile under solid state fermentation (SSF) were investigated. Initial moisture content and type of carbon source were consecutively optimized. Solid state fermentation in a laboratory horizontal bioreactor using the optimized medium allowed the production of 320 U g−1 of carbon source which compared favourably with those reported for other microorganisms. Optimal xylanase activity was observed at pH 5 and 70 °C. Chromogenic (fluorogenic) 4-methylumbelliferyl β-glycoside of xylobiose (MUX2) was used to characterize the xylanase multienzyme component, after separation by isoelectric focusing and native PAGE electrophoresis. The zymograms indicated one major xylanase fraction exhibiting pI and molecular mass values 4 and 90–120 kDa, respectively.
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