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41.
Nisin production of Lactococcus lactis N8 with hemin‐stimulated cell respiration in fed‐batch fermentation system
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In this study, nisin production of Lactococcus lactis N8 was optimized by independent variables of glucose, hemin and oxygen concentrations in fed‐batch fermentation in which respiration of cells was stimulated with hemin. Response surface model was able to explain the changes of the nisin production of L. lactis N8 in fed‐batch fermentation system with high fidelity (R2 98%) and insignificant lack of fit. Accordingly, the equation developed indicated the optimum parameters for glucose, hemin, and dissolved oxygen were 8 g L?1 h?1, 3 μg mL?1 and 40%, respectively. While 1711 IU mL?1 nisin was produced by L. lactis N8 in control fed‐batch fermentation, 5410 IU mL?1 nisin production was achieved within the relevant optimum parameters where the respiration of cell was stimulated with hemin. Accordingly, nisin production was enhanced 3.1 fold in fed‐batch fermentation using hemin. In conclusion the nisin production of L. lactis N8 was enhanced extensively as a result of increasing the biomass by stimulating the cell respiration with adding the hemin in the fed‐batch fermentation. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:678–685, 2015 相似文献
42.
Helmut Cölfen Thomas M. Laue Wendel Wohlleben Kristian Schilling Engin Karabudak Bradley W. Langhorst Emre Brookes Bruce Dubbs Dan Zollars Mattia Rocco Borries Demeler 《European biophysics journal : EBJ》2010,39(3):347-359
Progress in analytical ultracentrifugation (AUC) has been hindered by obstructions to hardware innovation and by software incompatibility. In this paper, we announce and outline the Open AUC Project. The goals of the Open AUC Project are to stimulate AUC innovation by improving instrumentation, detectors, acquisition and analysis software, and collaborative tools. These improvements are needed for the next generation of AUC-based research. The Open AUC Project combines on-going work from several different groups. A new base instrument is described, one that is designed from the ground up to be an analytical ultracentrifuge. This machine offers an open architecture, hardware standards, and application programming interfaces for detector developers. All software will use the GNU Public License to assure that intellectual property is available in open source format. The Open AUC strategy facilitates collaborations, encourages sharing, and eliminates the chronic impediments that have plagued AUC innovation for the last 20 years. This ultracentrifuge will be equipped with multiple and interchangeable optical tracks so that state-of-the-art electronics and improved detectors will be available for a variety of optical systems. The instrument will be complemented by a new rotor, enhanced data acquisition and analysis software, as well as collaboration software. Described here are the instrument, the modular software components, and a standardized database that will encourage and ease integration of data analysis and interpretation software. 相似文献
43.
Ulukaya E Acilan C Yilmaz M Yilmaztepe-Oral A Ari F Zik B Ursavas A Tokullugil AH 《Cell biochemistry and function》2010,28(7):565-570
The Fas/Fas Ligand (FasL) system and survivin have counteracting roles in cell survival. Therefore, we explored the role of circulating soluble Fas (sFas) and the tissue levels of Fas and survivin with regard to response to chemotherapy in lung cancer patients. Serum samples from 52 lung cancer patients and 54 control subjects (19 benign lung disease and 35 healthy control subjects) were collected prior to and 24 and 48 h after chemotherapy. sFas was statistically significantly higher in the cancer group than that in the control groups (p < 0.001). Baseline (before chemotherapy) sFas values showed a statistically significant inverse correlation with overall survival (r = ?0.599, p < 0.001). There was a significant increase in serum sFas levels 24 h after treatment (p < 0.05). Contrarily, tissue levels of Fas and survivin were not changed following the chemotherapy (p > 0,05). In conclusion, increased sFas may be an indicator of poor outcome in lung cancer patients. However, cisplatin‐based chemotherapy may not be effective via neither the Fas/FasL system nor survivin pathway. Indeed, larger sample size is required for further evaluation. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
44.
Elif Şahin Horasan Gülden Ersöz Musa Göksu Feza Otag Ahmet Oner Kurt Sevim Karaçorlu Ali Kaya 《Mycopathologia》2010,170(4):263-268
Objectives
We aimed to asses possible clinically significant differences between C. parapsilosis and other candida species candidemia receiving care in the intensive care unit (ICU) setting.Methods
The study included 118 adult patients diagnosed as candidemia after admission to the ICU of a university hospital between January 2004 and December 2009. Data about demographic characteristics, underlying diseases, and risk factors for ICU-related candidemia were collected.Results
During the study period, 118 patients with candidemia were identified among 2,853 patients admitted into the ICU. Candidemia was seen in 41.4 cases per 1,000 ICU admissions. The overall incidence of candidemia in ICU patients during the study period was 2.09 per 1,000 hospital admissions. Of the isolates, 18.6% were C. albicans and 81.4% were C. non-albicans. The species most frequently isolated was C. parapsilosis (66.1%, 78/118). The distribution of other Candida spp. was as follows: 15 had C. tropicalis (12.7%) and 3 had C. glabrata (2.5%). By Statistical analysis, when patients with candidemia who had C. parapsilosis were compared with other Candida spp., the following factors were found to be significantly associated with C. parapsilosis fungemia; intravascular catheters (p = 0.008), malignity (p = 0.049) and age (p = 0.039). Relationship was found between C. tropicalis and hematologic malignancies (p = 0.001).Conclusions
When infections with a high mortality such as candidemia is suspected in critically ill patients, it is important to know local risk factors and epidemiological distributions of causative agents in selection of empirical and effective antifungal treatment. 相似文献45.
M. Çankaya M. Şişecioğlu Ö. Barış M. Güllüce H. Özdemir 《Applied Biochemistry and Microbiology》2010,46(1):57-60
Bovine lactoperoxidase (LPO) was purified from skimmed milk using amberlite CG-50-H+ resin, CM sephadex C-50 ion-exchange chromatography, and sephadex G-100 gel filtration chromatography. Lactoperoxidase was purified 20.45-fold with a yield of 28.8%. Purity of enzyme checked by sodium dodecyl sulphate-polyacrylamide gel electrophoresis method and a single band was observed. K m was 0.25 mM at 20°C, V max value was 7.95 μmol/ml min at 20°C (pH 6.0). Antibacterial study was done by disk diffusion method of Kirby-Bauer using Mueller-Hinton agar medium with slight modification. Bovine LPO showed high antibacterial activity in 100 mM thiocyanate-100 mM H2O2 medium for some bacteria (Brevibacillus centrosaurus, B. choshinensis, B. lyticum, Cedecea davisae, Chryseobacterium indoltheticum, Clavibacter michiganense pv. insidiosum, Kocuria erythromyxa, K. kristinae, K. rosea, K. varians, Paenibacillus validus, Pseudomonas syringae pv. populans, Ralstonia pickettii, Rhodococcus wratislaviensis, Serratia fonticola, Streptomyces violaceusniger, Vibrio cholerae-nonO1) respectively, and compared with well known antibacterial substances (levofloxacin, netilmicin). LPO system has inhibition effects on all type bacteria and concentration is really important such as LPO-100 mM thiocyanate-100 mM H2O2 system was proposed as an effective agent against many factors causing several diseases. 相似文献
46.
Foot problems are common causes of morbidity in patients with diabetes mellitus. Foot ulcers are the leading cause of hospitalization in diabetic patients. Bones may be involved in two different clinical conditions: osteomyelitis and Charcot osteoarthropathy. Osteomyelitis usually develops by spreading from contiguous soft tissue to underlying bone. Charcot foot is deformation of foot as a result of muscle athrophy, bone and joint structure changes in a joint as a secondary complication of neuropathy. To distinguish bone infection from non-infectious bone disorders as in Charcot joint may be difficult, especially if there is no skin ulceration. So, the mere absence of skin ulcers does not exclude the diagnosis of osteomyelitis. 相似文献
47.
A new therapeutic approach in Alzheimer disease: some novel pyrazole derivatives as dual MAO-B inhibitors and antiinflammatory analgesics 总被引:1,自引:0,他引:1
Gökhan-Kelekçi N Yabanoğlu S Küpeli E Salgin U Ozgen O Uçar G Yeşilada E Kendi E Yeşilada A Bilgin AA 《Bioorganic & medicinal chemistry》2007,15(17):5775-5786
The increasing life expectancy in our population makes Alzheimer's disease (AD) a growing public health problem. There is a great need to find a way to prevent and delay the disease. It was shown that monoamine oxidase-B (MAO-B) inhibitors and antiinflammatory agents might be effective in treating AD. Therefore, a novel series of 1-thiocarbamoyl-3-substituted phenyl-5-(2-pyrrolyl)-4,5-dihydro-(1H)-pyrazole derivatives as promising MAO-B inhibitors was synthesized and investigated for the ability to inhibit selectively the activity of the A and B isoforms of monoamine oxidase (MAO). Most of the synthesized compounds showed high activity against both the MAO-A (compounds 3e-3h) and the MAO-B (compounds 3i-3l) isoforms. All the synthesized compounds were also tested for their in vivo antiinflammatory activity by two different bioassays namely, carrageenan-induced oedema and acetic acid-induced increase in capillary permeability in mice. In addition, analgesic and ulcerogenic activities were determined. The combined antiinflammatory data from in vivo animal models showed that compound 3k exhibited anti-inflammatory activity comparable to that of indomethacin with no ulcerogenic effects. Since compound 3k exhibits both antiinflammatory-analgesic activity and MAO-B inhibition, it needs further detailed studies. 相似文献
48.
Karakaya Songul Göger Gamze Bona Gülnur Ekşi Yuca Hafize Aydın Bilge Tekman Enes Şahin Aydan Acar Pınar Nur Münevver Güvenalp Zühal 《Protoplasma》2022,259(6):1493-1506
Protoplasma - Colchicum speciosum Steven species is a perennial stemless plant. C. speciosum is a flowering herb native to mountainous regions of northern Turkey, the Caucasus, and northern Iran.... 相似文献
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