1.Immobilizing engineered Escherichia coli cells into zeolitic imidazolate framework 8 for efficient biosynthesis of Ala-Gln.
Yingkang ZHANG ; Ting CHENG ; Feiyang ZHAO ; Yanqin YI ; Qingqing LI ; Zhenhua LU ; Mianbin WU ; Tao WANG ; Xiaohuan LIU
Chinese Journal of Biotechnology 2023;39(3):1131-1141
The α-amino acid ester acyltransferase (SAET) from Sphingobacterium siyangensis is one of the enzymes with the highest catalytic ability for the biosynthesis of l-alanyl-l-glutamine (Ala-Gln) with unprotected l-alanine methylester and l-glutamine. To improve the catalytic performance of SAET, a one-step method was used to rapidly prepare the immobilized cells (SAET@ZIF-8) in the aqueous system. The engineered Escherichia coli (E. coli) expressing SAET was encapsulated into the imidazole framework structure of metal organic zeolite (ZIF-8). Subsequently, the obtained SAET@ZIF-8 was characterized, and the catalytic activity, reusability and storage stability were also investigated. Results showed that the morphology of the prepared SAET@ZIF-8 nanoparticles was basically the same as that of the standard ZIF-8 materials reported in literature, and the introduction of cells did not significantly change the morphology of ZIF-8. After repeated use for 7 times, SAET@ZIF-8 could still retain 67% of the initial catalytic activity. Maintained at room temperature for 4 days, 50% of the original catalytic activity of SAET@ZIF-8 could be retained, indicating that SAET@ZIF-8 has good stability for reuse and storage. When used in the biosynthesis of Ala-Gln, the final concentration of Ala-Gln reached 62.83 mmol/L (13.65 g/L) after 30 min, the yield reached 0.455 g/(L·min), and the conversion rate relative to glutamine was 62.83%. All these results suggested that the preparation of SAET@ZIF-8 is an efficient strategy for the biosynthesis of Ala-Gln.
Escherichia coli/genetics*
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Glutamine
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Zeolites/chemistry*
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Amino Acids
2.Effectiveness of thymoquinone, zeolite, and platelet-rich plasma in model of corrosive oesophagitis induced in rats.
Gökhan KARACA ; Oktay AYDIN ; Faruk PEHLIVANLI ; Canan ALTUNKAYA ; Hafize UZUN ; Osman GÜLER
Annals of Surgical Treatment and Research 2017;92(6):396-401
PURPOSE: The effectiveness of platelet-rich plasma (PRP), thymoquinone, and zeolite in corrosive esophageal burns was investigated in a rat model. METHODS: Four groups were comprised as containing 10 rats in each group. For group I, oesophagitis was induced and no other procedure was performed (control group). For group II, oesophagitis was induced and thymoquinone was administered for 1 week via oral gavage once a day (thymoquinone group). For group III, oesophagitis was induced for 1 week via oral gavage once a day (PRP group). For group IV, oesophagitis was induced and zeolite was administered for 1 week via oral gavage once a day (zeolite group). On the 10th day, the rats were sacrificed under anaesthesia and venous blood sampling was performed from the vena portae. The oesophaguses were totally excised. Biochemically, interleukin (IL)-1B, IL-6, TNF-α, and MCP-1 were examined from venous blood. Inflammation score was evaluated histopathologically in oesophageal tissue that was collected. RESULTS: There was a statistically significant difference among groups in terms of IL-1, IL-6, MCP levels, compared to the control group; median IL-1, IL-6, MCP levels of thymoquinone, PRP, and zeolite groups were statistically significantly lower. There was a statistically significant difference among groups in terms of inflammation scores, compared to group I; median inflammation scores of groups II, III and IV were statistically significantly lower thymoquinone. CONCLUSION: PRP, and zeolite exhibited positive effect on recovery in oesophagitis by reducing inflammation in the involved segment.
Animals
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Burns
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Inflammation
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Interleukin-1
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Interleukin-6
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Interleukins
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Models, Animal
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Platelet-Rich Plasma*
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Rats*
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Zeolites*
3.Optimization of ethylene production from ethanol dehydration using Zn-Mn-Co/HZSM-5 by response surface methodology.
Wei WANG ; Keke CHENG ; Jianwei XUE ; Jian'an ZHANG
Chinese Journal of Biotechnology 2011;27(3):412-418
The effects of reaction temperature, ethanol concentration and weight hourly space velocity (WHSV) on the ethylene production from ethanol dehydration using zinc, manganese and cobalt modified HZSM-5 catalyst were investigated by response surface methodology (RSM). The results showed that the most significant effect among factors was reaction temperature and the factors had interaction. The optimum conditions were found as 34.4% ethanol concentration, 261.3 0 degrees C of reaction temperature and 1.18 h(-1) of WHSV, under these conditions the yield of ethylene achieved 98.69%.
Catalysis
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Cobalt
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chemistry
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Dehydration
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Ethanol
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chemistry
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Ethylenes
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chemistry
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metabolism
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Manganese
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chemistry
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Zeolites
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chemistry
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Zinc
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chemistry
4.Influence of ZSM-5(38)/Al-MCM-41 composite molecular sieve catalysts on pyrolysis of cellulose.
Xiaojuan LIU ; Fengwen YU ; Yong NIE ; Yao LUO ; Jianbing JI
Chinese Journal of Biotechnology 2011;27(3):398-403
Pyrolysis of cellulose with different catalysts has been conducted in a fixed-bed reactor. Micro-mesoporous composite molecular sieves of ZSM-5(38)/A1-MCM-41 with different Si/A1 ratios were prepared under hydrothermal conditions. With powder X-ray diffraction (XRD), the catalyst samples were characterized. GC-MS was used to analyze the bio-oil composition. The effects of catalysts on the pyrolysis product yields were investigated and the results were compared with the results of experiments performed without catalyst under the same pyrolitic conditions. The presence of the catalysts decreased the liquid yield, while increased the moisture content. The major improvement in the quality of bio-oil with the use of catalysts was the increase of DL-2,3-Butanediol. ZSM-5(38)/A1-MCM-41(20) favored the formation of phenol and 2-methoxy-phenol. In addition, these catalysts were all benefit for the generation of small molecular compounds. Also, it was found that ZSM-5(38) was better for the production of C4-C5 compounds. And micro-mesoporous composite molecular sieves mainly promoted the production of C6-C8 compounds.
Catalysis
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Cellulose
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metabolism
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Plant Oils
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metabolism
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Refuse Disposal
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Silicon Dioxide
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chemistry
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Zeolites
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chemistry
5.Research progress of novel porous hemostatic agents.
Chao-Yun XI ; Yuan ZHUANG ; De-Qing WANG
Journal of Experimental Hematology 2013;21(2):526-529
The treatment of bleeding wound of solid visceral and the rescue of uncontrollable bleeding are still confronted with difficulties in surgery and first-aid field. Many researchers devote to study in the field of hemostasis, and the novel porous hemostatic agent is one of the hot spot of research about hemostasis. The review focuses on the hemostatic effect, properties, hemostatic mechanism, shortcoming and future trends of three novel porous hemostatic agents such as polysaccharides, zeolite and wollastonite.
Calcium Compounds
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Hemorrhage
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therapy
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Hemostatic Techniques
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Hemostatics
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administration & dosage
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chemistry
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Humans
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Polysaccharides
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Porosity
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Silicates
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Zeolites
6.Preparation of seeding type immobilized microorganisms and their degradation characteristics on Di-n-butyl phthalate.
Lin WANG ; Qi-Fang LUO ; Jin-Hui ZHAO ; Xiao-He ZHANG ; Li-Jing HUANG
Biomedical and Environmental Sciences 2006;19(2):147-152
OBJECTIVETo study the preparation of seeding type immobilized microorganisms and their degradation characteristics on di-n-butyl phthalate (DBP).
METHODSDiatomite, clinoptilolite, silk zeolite, and coal fly ash were chosen as reserved materials and modified. Their adsorption capacity and intensity in the bacteria were determined and the best carrier was picked out. The seeding type immobilized microorganisms were prepared by the best carrier and then it degraded DBP under different primary concentration, vibration rate, pH, temperature in the presence of metal compounds.
RESULTSThe adsorption capacity of the modified coal fly ash, silk zeolite, clinoptilolite and zeolite was 44.2%, 71.6%, 84.0%, and 94.4%, respectively, which was 1.66, 1.49, 1.37, and 1.16 times as high as that of their natural state. Their adsorption intensity was 72.1%, 90.5%, 90.1%, and 91.1% in turn. The modified diatomite was selected to prepare the seeding type immobilized microorganisms. When the primary DBP concentration was 100 to 500 mg/L, the DBP-degraded rate of the immobilized microorganisms could be above 80%. The degradation activity of both the dissociative and immobilized microorganisms was higher in vibration than in stillness. When pH was 6.0 to 9.0, the DBP-degraded rate of the immobilized microorganisms was above 82%, which was higher than the dissociative microorganisms. When the temperature was between 20 degrees C and 40 degrees C, the DBP-degraded rate could reach 84.5% in 24 h. The metal compounds could inhibit the degradation activity of both the dissociative and immobilized microorganisms. The degradation process of the immobilized microorganisms could be described by the first-order model.
CONCLUSIONThe adsorption capacity of the diatomite, clinoptilolite, silk zeolite and coal fly ash on DBP-degrading bacteria can be improved obviously after they are modified. The modified diatomite is best in terms of its adsorption capacity and intensity. Its seeding type immobilized microorganisms could degrade DBP effectively and is more adaptable to DBP load, temperature, pH than the dissociative microorganisms. The metal compounds could inhibit the activity of both the immobilized and dissociative microorganisms. The degradation reaction of the immobilized microorganisms on DBP is consistent with the first-order model.
Adsorption ; Bacteria ; metabolism ; Biodegradation, Environmental ; Biotechnology ; methods ; Cells, Immobilized ; Diatomaceous Earth ; Dibutyl Phthalate ; metabolism ; Hydrogen-Ion Concentration ; Kinetics ; Temperature ; Zeolites
7.Clinical and Prognostic Features of Erionite-Induced Malignant Mesothelioma.
Ersin DEMIRER ; Christian F GHATTAS ; Mohamed O RADWAN ; Elamin M ELAMIN
Yonsei Medical Journal 2015;56(2):311-323
This review analytically examines the published data for erionite-related malignant pleural mesothelioma (E-MPM) and any data to support a genetically predisposed mechanism to erionite fiber carcinogenesis. Adult patients of age > or =18 years with erionite-related pleural diseases and genetically predisposed mechanisms to erionite carcinogenesis were included, while exclusion criteria included asbestos- or tremolite-related pleural diseases. The search was limited to human studies though not limited to a specific timeframe. A total of 33 studies (31042 patients) including 22 retrospective studies, 6 prospective studies, and 5 case reports were reviewed. E-MPM developed in some subjects with high exposures to erionite, though not all. Chest CT was more reliable in detecting various pleural changes in E-MPM than chest X-ray, and pleural effusion was the most common finding in E-MPM cases, by both tests. Bronchoalveolar lavage remains a reliable and relatively less invasive technique. Chemotherapy with cisplatin and mitomycin can be administered either alone or following surgery. Erionite has been the culprit of numerous malignant mesothelioma cases in Europe and even in North America. Erionite has a higher degree of carcinogenicity with possible genetic transmission of erionite susceptibility in an autosomal dominant fashion. Therapeutic management for E-MPM remains very limited, and cure of the disease is extremely rare.
Adult
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Asbestos/*adverse effects
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Asbestos, Amphibole
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Environmental Exposure/*adverse effects
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Female
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Humans
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Lung Neoplasms/*chemically induced/radiography
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Male
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Mesothelioma/*chemically induced/radiography
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Middle Aged
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Pleura/radiography
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Pleural Effusion/radiography
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Pleural Neoplasms/*chemically induced/radiography
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Prognosis
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Prospective Studies
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Retrospective Studies
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Tomography, X-Ray Computed
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Zeolites/*adverse effects