1.Letter to the editor: Respective Contribution of Liquid and Solid Media to Mycobacterial Yields from Pleural Fluid in Tuberculous Pleural Effusion.
Chang Ho KIM ; Seung Ick CHA ; Jaehee LEE
Journal of Korean Medical Science 2015;30(12):1922-1923
No abstract available.
Automation, Laboratory/*methods
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Culture Media/*classification
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Female
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Humans
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Male
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Sputum/*microbiology
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Tuberculosis, Pleural/*diagnosis
2.Comparison of 2,3-butanediol production by several strains and optimization of the fermentation medium.
Yuanquan SONG ; Ruchun WU ; Yunzhen XU ; Ming FAN ; Dehua LIU
Chinese Journal of Biotechnology 2011;27(3):489-492
Five Klebsiella pneumonia strains (including two strains whose genes for lactic acid were knocked out) were used to produce 2,3-butanediol, in which K. pneumonia HR521 LDH (gene for lactic acid was knocked out) was the best for the production, and then the fermentation medium was optimized by orthogonal design. The optimum compositions were as follows: glucose 90 g/L, (NH4)2HPO4 3 g/L, CLSP 6 g/L, sodium acetate 5 g/L, KCl 0.4 g/L, MgSO4 0.1 g/L, FeSO4 x 7H2O 0.02 g/L, MnSO4 0.01 g/L. Under the above conditions, final concentration of acetone and 2,3-butanediol could reach 37.46 g/L, 10 g/L higher than that under the initial conditions, the yield was 90.53% of the theory, and the productivity was 1.5 g/(L-h), and no lactic acid was detected, which could be benefit for the downstream processing and industrial application.
Butylene Glycols
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metabolism
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Culture Media
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chemistry
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Fermentation
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Gene Knockout Techniques
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Glucose
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metabolism
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Klebsiella pneumoniae
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classification
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genetics
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growth & development
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metabolism
3.Study of cellulolytic soil fungi and two nova species and new medium.
Mahmood KHALID ; Wei-Jun YANG ; Nazir KISHWAR ; Zahid Iqbal RAJPUT ; Abdullah G ARIJO
Journal of Zhejiang University. Science. B 2006;7(6):459-466
This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 degrees C for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including 2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency (45% and 36% respectively), as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium.
Aspergillus
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isolation & purification
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metabolism
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Cellulose
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metabolism
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Culture Media
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Mitosporic Fungi
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classification
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isolation & purification
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metabolism
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Penicillium
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isolation & purification
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metabolism
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Soil Microbiology
4.Optimization of succinic acid fermentation with Actinobacillus succinogenes by response surface methodology.
Naikun SHEN ; Yan QIN ; Qingyan WANG ; Nengzhong XIE ; Huizhi MI ; Qixia ZHU ; Siming LIAO ; Ribo HUANG
Chinese Journal of Biotechnology 2013;29(10):1473-1483
Succinic acid is an important C4 platform chemical in the synthesis of many commodity and special chemicals. In the present work, different compounds were evaluated for succinic acid production by Actinobacillus succinogenes GXAS 137. Important parameters were screened by the single factor experiment and Plackeet-Burman design. Subsequently, the highest production of succinic acid was approached by the path of steepest ascent. Then, the optimum values of the parameters were obtained by Box-Behnken design. The results show that the important parameters were glucose, yeast extract and MgCO3 concentrations. The optimum condition was as follows (g/L): glucose 70.00, yeast extract 9.20 and MgCO3 58.10. Succinic acid yield reached 47.64 g/L at the optimal condition. Succinic acid increased by 29.14% than that before the optimization (36.89 g/L). Response surface methodology was proven to be a powerful tool to optimize succinic acid production.
Actinobacillus
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classification
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genetics
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metabolism
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Bioreactors
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Culture Media
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metabolism
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Fermentation
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Glucose
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metabolism
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Industrial Microbiology
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methods
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Succinic Acid
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metabolism
5.Identification and mode of action of a xylanase A purified from the culture filtrate of Bacillus pumilus WL-11.
Chinese Journal of Biotechnology 2005;21(3):407-413
Microbial xylanases have received a great deal of attention in the last two decades for their potential applications in food, paper making and animal feed industries. Bacillus pumilus WL-11 was identified as a producer of alkane xylanase free of cellulase after screening soil samples of paper-making factories. The xylanase A (XylA) was purified to homogeneity from the culture filtrate of Bacillus pumilus WL-11 by (NH4) 2SO4 precipitation, CM-Sephadex and Sephadex G-75 chromatographies. The molecular mass of XylA is estimated to be 26.0 kD by SDS-PAGE and its isoelectric point is 9.5. The apparent Km is 16.6 mg/mL and V(max) is 1263 micromol/(min x mg) towards oat spelt xylan. XylA is optimally active between pH 7.2 and 8.0, and stable at pH 6.0 to 10.4. The enzyme is optimally active at 45 degrees C - 55 degrees C and stable at temperature below 45 degrees C, with its half time of activity of 35 min and 15 min at 55 degrees C and 60 degrees C respectively. HPLC analysis revealed that hydrolysis patterns of xylans from oat spelt, birch wood and beech wood by purified XylA were different. The XylA is determined to be an endo-beta-1,4-xylanase, as it generated mainly xylotriose and no xylose was detected among the three hydrolysates. XylA has strong hydrolytic activity towards the pentose in the hydrolysates of beech wood and birch wood xylans, but was not active to the pentose in the hydrolysate of oat spelt xylan. The crude WL-11 enzyme can efficiently hydrolyze oat spelt xylan to a series of xylo-oligosaccharides, suggesting its potential application in nutraceutical industry.
Bacillus
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classification
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enzymology
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Bacterial Proteins
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metabolism
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Culture Media
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Endo-1,4-beta Xylanases
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isolation & purification
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metabolism
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Substrate Specificity
6.Characteristic comparison of mouse primary macrophages cultured in L929 cell conditioned medium.
Wei WANG ; Yi QIN ; Yaru WANG ; Jiejie ZOU ; Jing CHEN ; Jinwu CHEN ; Yan ZHANG ; Ming GENG ; Zhongdong XU ; Min DAI ; Lilong PAN
Chinese Journal of Biotechnology 2020;36(7):1431-1439
The purpose of this study is to provide a culture for mouse bone marrow-derived macrophages (BMDM) and peritoneal macrophages (PM) and to characterize their molecular and cellular biology. The cell number and purity from the primary culture were assessed by cell counter and flow cytometry, respectively. Morphological features were evaluated by inverted microscope. Phagocytosis by macrophages was detected by the neutral red dye uptake assay. Phenotypic markers were analyzed by real-time fluorescent quantitative PCR. Our results show that the cell number was much higher from culture of BMDM than PM, while there was no significant difference regarding the percentage of F4/80+CD11b+ cells (98.30%±0.53% vs. 94.83%±1.42%; P>0.05). The proliferation rate of BMDM was significantly higher than PM in the presence of L929 cell conditioned medium, by using CCK-8 assay. However, PM appeared to adhere to the flask wall and extend earlier than BMDM. The phagocytosis capability of un-stimulated BMDM was significantly higher than PM, as well as lipopolysaccharide (LPS)-stimulated BMDM, except the BMDM stimulated by low dose LPS (0.1 μg/mL). Furthermore, Tnfα expression was significantly higher in un-stimulated BMDM than PM, while Arg1 and Ym1 mRNA expression were significantly lower than PM. The expression difference was persistent if stimulated by LPS+IFN-γ or IL-4. Our data indicate that bone marrow can get larger amounts of macrophages than peritoneal cavity. However, it should be aware that the molecular and cellular characteristics were different between these two culture systems.
Animals
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Bone Marrow Cells
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physiology
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Cells, Cultured
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Culture Media, Conditioned
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Lipopolysaccharides
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metabolism
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Macrophages
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classification
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physiology
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Mice
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Phagocytosis
7.Carbon metabolism and energetic utilization of Synechococcus sp. PCC7942 under mixotrophic condition.
Riming YAN ; Zhibin ZHANG ; Qinggui ZENG ; Zhu DU ; Ju CHU
Chinese Journal of Biotechnology 2010;26(9):1239-1248
To investigate the energy utilization efficiency of Synechococcus sp. PCC7942 under mixotrophic conditions, we studied its growth characteristics in mixotrophic cultures with glucose and acetic acid respectively and discussed the carbon metabolism and energy utilization based on metabolic flux analysis. Results showed that both glucose and acetate could better enhance the growth of Synechococcus sp. PCC7942, and the latter was more effective. The metabolic flux through glycolytic pathway in mixotrophic cultures was stimulated by glucose whereas depressed by acetate, while the flux through the tricarboxylic acid cycle increased in both cases. Under mixotrophic conditions, glucose makes more significant impact on the diminishment of photochemical efficiency of Synechococcus sp. PCC7942. Although the contribution of light energy was smaller, the cell yields based on total energy in mixotrophic cultures were higher comparing with photoautotrophic culture. The energy conversion efficiencies based on ATP synthesis in photoautotrophic culture, mixotrophic cultures with glucose and with acetate were evaluated to be 6.81%, 7.43% and 8.77%, respectively.
Acetic Acid
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pharmacology
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Adenosine Triphosphate
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biosynthesis
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Carbon
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metabolism
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Culture Media
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Culture Techniques
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methods
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Energy Metabolism
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Glucose
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pharmacology
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Synechococcus
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classification
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growth & development
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metabolism
8.Adaptability of oleaginous microalgae Chlorococcum alkaliphilus MC-1 cultivated with flue gas.
Xi YANG ; Wenzhou XIANG ; Feng ZHANG ; Hualian WU ; Hui HE ; Jiewei FAN
Chinese Journal of Biotechnology 2013;29(3):370-381
In order to lower the cost of lipid production of microalgae and reduce greenhouse gas emissions, microalgae Chlorococcum alkaliphilus MC-1 with the characteristics of rapid pH drift and high pH adaptability, was cultivated with bubbling of flue gas. The experiment was first performed in the photobioreactor (15 L) in three groups (control group, CO2 group and flue gas group), then, in the open raceway pond (24 m2). The adaptability of microalgae MC-1 to the cultivation with flue gas was studied. The results showed that the maximum biomass concentration, growth rate, total lipid content and CO2 fixation rate were (1.02+/-0.07) g/L, (0.12+/-0.02) g/(L.d), (37.84+/-0.58)% and (0.20+/-0.02) g/(L.d) in the photobioreactor treated with flue gas, 36%, 33.33%, 15.34% and 33.33% higher than those of the CO2 group, respectively. In the open raceway pond with aeration of flue gas, the maximum biomass concentration, growth rate, total lipid content and CO2 fixation rate were 147.40 g/m2, 14.73 g/(m2.d), 35.72% and 24.01 g/(m2.d), respectively, which were similar to the cultivation with pure CO2. The toxic heavy metal contents (Pb, As, Cd and Cr) in the biomass of MC-1 treated with flue gas were all below the legal limits. Additionally, the absorptive effect of CO2, NO and SO2 were determined. In the photobioreactor and open raceway pond, the average absorption ratios of these gases were all higher than previous studies. Therefore, our study showed that MC-1 can adapt to the cultivation with flue gas, and it is feasible to enlarge the outdoor cultivation of MC-1 for lipid production coupling with emissions reduction of flue gas.
Adaptation, Physiological
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physiology
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Carbon Dioxide
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chemistry
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Chlorophyta
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classification
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growth & development
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physiology
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Culture Media
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metabolism
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Culture Techniques
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methods
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Gases
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chemistry
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Microalgae
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classification
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growth & development
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physiology
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Nitric Oxide
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chemistry
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Sulfur Dioxide
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chemistry
9.Purification and characterization of a beta-D-xylosidase from Leifsonia shinshuensis DICP 16.
Hongwei LUAN ; Ying HU ; Xingbao LIU ; Dacheng HAO ; Ling YANG
Chinese Journal of Biotechnology 2008;24(5):867-873
A beta-D-xylosidase from Leifsonia shinshuensis DICP 16 was purified to apparent homogeneity using a combination of ammonium sulfate precipitation, DE 52 anion-exchange, Q-Sepharose Fast Flow anion-exchange, Toyopearl Butyl 650C hydrophobic-interaction and Sephacryl S-300 HR gel-permeation chromatography. The purified xylosidase consisted of two same subunits and had the relative molecular weight of 180 kD as determined by SDS-PAGE and gel-permeation chromatography. The maximal beta-D-xylosidase activity occurred at 55 degrees C and pH 7.0. It was stable at 45 degrees C and retained its original activity for 60 min. The stability declined rapidly when the temperature rose above 55 degrees C. The xylosidase was stable in the pH range from 6.0 to 11.0 for 20 h. At pH 7.0 and 45 degrees C the Km for p-nitrophenyl-beta-D-xylopyranoside (pNPX) was 1.04 mmol/L and the Vmx was 0.095 mmol nitrophenol/min/mg xylosidase. The enzyme was inhibited strongly by Fe2+ and Cu2+. It exhibited low levels of activity against other artificial substrates, compared to its activity against pNPX. When different natural xylosides were used as the substrates, the xylosidase showed distinct hydrolysis ability. It could hydrolyze 20-C, beta-(1-->6)-xyloside of ginsenoside Rb3 (G-Rb3) into ginsenoside Rd, but did not hydrolyze the other beta-D-glucosidic bonds of G-Rb3. Additionally, the xylosidase could not hydrolyze C-7 xylosyl-bearing taxanes.
Actinomycetales
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classification
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enzymology
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Amino Acid Sequence
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Culture Media
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Hydrogen-Ion Concentration
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Molecular Sequence Data
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Sequence Analysis, Protein
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Temperature
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Xylosidases
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chemistry
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genetics
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isolation & purification