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Approaching Ultimate Synthesis Reaction Rate of Ni-Rich Layered Cathodes for Lithium-Ion Batteries
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作者 Zhedong Liu Jingchao Zhang +9 位作者 Jiawei Luo Zhaoxin Guo Haoran Jiang Zekun Li Yuhang Liu Zijing Song Rui Liu Wei-Di Liu Wenbin Hu Yanan Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期392-402,共11页
Nickel-rich layered oxide LiNi_(x)Co_(y)MnzO_(2)(NCM,x+y+z=1)is the most promising cathode material for high-energy lithium-ion batteries.However,conventional synthesis methods are limited by the slow heating rate,slu... Nickel-rich layered oxide LiNi_(x)Co_(y)MnzO_(2)(NCM,x+y+z=1)is the most promising cathode material for high-energy lithium-ion batteries.However,conventional synthesis methods are limited by the slow heating rate,sluggish reaction dynamics,high energy consumption,and long reaction time.To overcome these chal-lenges,we first employed a high-temperature shock(HTS)strategy for fast synthesis of the NCM,and the approaching ultimate reaction rate of solid phase transition is deeply investigated for the first time.In the HTS process,ultrafast average reaction rate of phase transition from Ni_(0.6)Co_(0.2)Mn_(0.2)(OH)_(2) to Li-containing oxides is 66.7(%s^(-1)),that is,taking only 1.5 s.An ultrahigh heating rate leads to fast reaction kinetics,which induces the rapid phase transition of NCM cathodes.The HTS-synthesized nickel-rich layered oxides perform good cycling performances(94%for NCM523,94%for NCM622,and 80%for NCM811 after 200 cycles at 4.3 V).These findings might also assist to pave the way for preparing effectively Ni-rich layered oxides for lithium-ion batteries. 展开更多
关键词 Nickel-rich layered oxides High-temperature shock Solid reaction kinetics Phase transition Reaction rate
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Procedure for preparing peptide-major histocompatibility complex tetramers for direct quantification of antigen-specific cytotoxic T lymphocytes 被引量:16
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作者 Xian-Hui He Li-Hui Xu Yi Liu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第27期4180-4187,共8页
AIM: To establish a simplified method for generating peptide-major histocompatibility complex (MHC) class I tetramers.METHODS: cDNAs encoding the extracellular domain of human lymphocyte antigen (HLA)-A*0201 he... AIM: To establish a simplified method for generating peptide-major histocompatibility complex (MHC) class I tetramers.METHODS: cDNAs encoding the extracellular domain of human lymphocyte antigen (HLA)-A*0201 heavy chain (A2) and β2-microglobulin (132m) from total RNA extracted from leukocytes of HLA-A2+ donors were doned into separate expression vectors by reverse transcription-polymerase chain reaction. The recombinant A2 and 132m proteins were expressed in ~/a oo/i^uain BL21(DE3) and recovered from the inclusion body fraction. Soluble A2 proteins loaded with specific antigen peptides were refolded by dilution from the heavy chain in the presence of light chain 132m and HLA-A2-restricted peptide antigens. The refolded A2 monomers were biotinylated with a commercial biotinylation enzyme (BirA) and purified by low pressure anion exchange chromatography on a Q-Sepharose (fast flow) column.The tetramers were then formed by mixing A2 monomers with streptavidin-PE in a molar ratio of 4:1. Flow cytometry was used to confirm the expected tetramer staining of CD8^+ T cells.RESULTS: Recombinant genes for HLA-A*0201 heavy chain (A2) fused to a BirA substrate peptide (A2-BSP) and mature β2m from HLA-A2+ donor leukocytes were successfully doned and highly expressed in E. coli, Two soluble monomeric A2-peptide complexes were reconstituted from A2-BSP in the presence of 132m and peptides loaded with either human cytomegalovirus pp65495-503 peptide (NLVPMVATV,NLV; designated as A2-NLV) or influenza virus matrix protein Mp58-66 peptide (GILGFVFTL, GIL; designated as A2-GIL). Refolded A2-NLV or A2-GIL monomers were biotinylated and highly purified by single step anion exchange column chromatography. The tetramers were then formed by mixing the biotinylated A2-NLV or A2-GIL monomers with streptavidin-PE, leading to more than 80% multiplicationas revealed by SDS-PAGE under non-reducing, unboiled conditions. Flow cytometry revealed that these tetramers could specifically bind to CD8^+ T cells from a HLA-A2^+ donor,but failed to bind to those from a HLA-A2- donor.CONCLUSION: The procedure is simple and efficient for generating peptide-MHC tetramers. 展开更多
关键词 Cloning Molecular HLA-A Antigens HLA-A2 Antigen Humans Recombinant Fusion Proteins Research Support Non-U.S. Gov't T-Lymphocytes Cytotoxic beta 2-Microglobulin
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Advances in the Research and Development of Acrylic Acid Production from Biomass 被引量:9
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作者 许晓波 林建平 岑沛霖 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第4X期419-427,共9页
关键词 RENEWABLE resource ACRYLIC ACID BIOMASS LACTIC ACID
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Advances in the Research and Development of Acrylic Acid Production from Biomass 被引量:12
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作者 许晓波 林建平 岑沛霖 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第4期419-427,共9页
The shortage of petroleum has resulted in worldwide efforts to produce chemicals from renewable resources. Among these attempts, the possibility of producing acrylic acid from biomass has caught the eye of many resear... The shortage of petroleum has resulted in worldwide efforts to produce chemicals from renewable resources. Among these attempts, the possibility of producing acrylic acid from biomass has caught the eye of many researchers. Converting the carbohydrates first to lactic acid by fermentation and then dehydrating lactic acid to acrylic acid is hitherto the most effective way for producing acrylic acid from biomass. While the lactic acid fer- mentation has been commercialized since longer times, the dehydration process of lactic acid is still under development because of its low yield. Further efforts should be made before this process became economically feasible. Because of the existence of acrylic acid pathways in some microorganisms, strain improvement and metabolic engineering provides also a possibilitv to produce acrylic acid directly from biomass by fermentation. 展开更多
关键词 renewable resource acrylic acid BIOMASS lactic acid
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Evaluation of Catalysts and Optimization of Reaction Conditions for the Dehydration of Methyl Lactate to Acrylates 被引量:8
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作者 张金锋 林建平 +1 位作者 许晓波 岑沛霖 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第2期263-269,共7页
The production of acrylates from biomass-originated lactic acid is of extraordinary importance, to overcome the increasing worldwide shortage of petroleum. In this study, the catalytic dehydration of methyl lactate ov... The production of acrylates from biomass-originated lactic acid is of extraordinary importance, to overcome the increasing worldwide shortage of petroleum. In this study, the catalytic dehydration of methyl lactate over a calcium sulfate catalyst, with various promoters, has been carried out to identify potential catalyst/promoter combinations for acrylate production. The best catalyst for methyl acrylate formation in this study has been calcium sulfate, with cupric sulfate and phosphates as promoters. The optimal mass ratio of m(CaSOa) : m(CuSOa) : m(Na2HPO4) : m(KH2PO4) is 150.0 : 13.8 : 2.5 : 1.2. Effects of carrier gas, reaction temperature, feed concentration as well as contact time on the dehydration of methyl lactate have been investigated. With nitrogen as a carrier gas, a combined yield of acrylic acid and methyl acrylate is 63.9% from 60% (by mass) methyl lactate at 400℃ with 7.7 seconds contact time. 展开更多
关键词 ACRYLATE contact time cupric sulfate DEHYDRATION promoters
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Recent progress of advanced anode materials of lithium-ion batteries 被引量:17
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作者 Hui Cheng Joseph G.Shapter +1 位作者 Yongying Li Guo Gao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第6期451-468,I0011,共19页
The rapid development of electric vehicles and mobile electronic devices is the main driving force to improve advanced high-performance lithium ion batteries(LIBs).The capacity,rate performance and cycle stability of ... The rapid development of electric vehicles and mobile electronic devices is the main driving force to improve advanced high-performance lithium ion batteries(LIBs).The capacity,rate performance and cycle stability of LIBs rely directly on the electrode materials.As far as the development of the advanced LIBs electrode is concerned,the improvement of anode materials is more urgent than the cathode materials.Industrial production of anode materials superior to commercial graphite still faces some challenges.This review sets out the most basic LIBs anode material design.The reaction principles and structural design of carbon materials,various transition metal oxides,silicon and germanium are summarized,and then the progress of other anode materials are analyzed.Due to the rapid development of metal organic frameworks(MOFs)in energy storage and conversion in recent years,the synthesis process and energy storage mechanism of nanostructures derived from MOF precursors are also discussed.From the perspective of novel structural design,the progress of various MOFs-derived materials for alleviating the volume expansion of anode materials is discussed.Finally,challenges for the future development of advanced anode materials for LIBs will be considered. 展开更多
关键词 Anode materials LIBS NANOMATERIALS Metal organic frameworks
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Space-flight Mutation of Streptomyces gilvosporeus for Enhancing Natamycin Production 被引量:6
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作者 梁景乐 林建平 +2 位作者 徐志南 苏薇 岑沛霖 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第5期720-724,共5页
Mutants of the strain producing natamycin, Streptomyces gilvosporeus, were obtained after space-flight mutation. With respect to the sand spores and slant spores, the mutation ratios were up to 67.6% and 78.3% and the... Mutants of the strain producing natamycin, Streptomyces gilvosporeus, were obtained after space-flight mutation. With respect to the sand spores and slant spores, the mutation ratios were up to 67.6% and 78.3% and the survival ratio was 43.1% and 3.0%, respectively. An improved mutant producing natamycin, S. gilvosporeus LK-45, was screened, which showed natamycin productivity of 1420mg·L^-1. A mutant resistant to 2-deoxy glucose, S.gilvosporeus LK-119, was further obtained using a'rational screening procedure. The natamycin productivity of 1940mg·L^-1 was achieved when glucose was used as the carbon source. 展开更多
关键词 space-flight mutation Streptomyces gilvosporeus NATAMYCIN rational screening 2-deoxy glucose
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Drug Nanorod-Mediated Intracellular Delivery of microRNA-101 for Self-sensitization via Autophagy Inhibition 被引量:6
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作者 Xiaofei Xin Xiaoqing Du +3 位作者 Qingqing Xiao Helena SAzevedo Wei He Lifang Yin 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第4期453-468,共16页
Autophagy is closely related to the drug resistance and metastasis in cancer therapy.Nanoparticlemediated co-delivery of combinatorial therapy with small-molecular drugs and nucleic acids is promising to address drug ... Autophagy is closely related to the drug resistance and metastasis in cancer therapy.Nanoparticlemediated co-delivery of combinatorial therapy with small-molecular drugs and nucleic acids is promising to address drug resistance.Here,a drug-delivering-drug(DDD)platform consisting of anti-tumor-drug nanorods as a vehicle for cytosol delivery of nucleic acid(miR-101)with potent autophagic-inhibition activity is reported for combinatorial therapy.The developed 180-nm nanoplatform,with total drug loading of up to 66%,delivers miR-101 to cancer cells,with threefold increase in intracellular level compared to conventional gene carriers and inhibits the autophagy significantly,along with above twofold reduction in LC3II mRNA and approximately fivefold increase in p62 mRNA over the control demonstrated in the results in vivo.And in turn,the delivery of miR-101 potentiates the drug’s ability to kill cancer cells,with a threefold increase in apoptosis over that of chemotherapy alone.The anti-tumor study in vivo indicates the combined therapy that enables a reduction of 80%in tumor volume and>twofold increase in apoptosis than of the single-drug strategy.In summary,via the carrier-free strategy of DDD,this work provides a delivery platform that can be easily customized to overcome drug resistance and facilitates the delivery of combined therapy of small-molecular drugs and nucleic acids. 展开更多
关键词 NANOCRYSTALS MICRORNA delivery AUTOPHAGY INHIBITION CYTOTOXICITY Combinatorial therapy
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Experimental infection of Z:ZCLA Mongolian gerbils with human hepatitis E virus 被引量:3
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作者 Yan Hong Zhuo-Jing He +3 位作者 Wei Tao Ting Fu Yan-Kun Wang Yong Chen 《World Journal of Gastroenterology》 SCIE CAS 2015年第3期862-867,共6页
AIM:To investigate whether Z:ZCLA Mongolian gerbils are readily susceptible to infection by human hepatitis E virus(HEV).METHODS:Z:ZCLA Mongolian gerbils were infected with a clinical HEV strain isolated from an acute... AIM:To investigate whether Z:ZCLA Mongolian gerbils are readily susceptible to infection by human hepatitis E virus(HEV).METHODS:Z:ZCLA Mongolian gerbils were infected with a clinical HEV strain isolated from an acutehepati tis E patient,and virus pathogenesis was assessed in this host.Non-infected gerbils served as the control group.Feces samples from gerbils were collected weekly for reverse transcription-nested polymerase chain reaction.Serum anti-HEV Ig G and alanine aminotransferase(ALT) were detected by enzyme linked immunosorbent assay.At sacrifice,each animal's liver,spleen and kidney were collected for histopathologic examination.RESULTS:HEV-infected gerbils showed fatigue,with histopathological changes observed in the liver,spleen and kidney.HEV RNA was detected in fecal samples taken at day 7 after inoculation and the detectable levels lasted out to day 42 after inoculation.Interestingly,ALT levels were only moderately increased in the HEV-infected animals compared with the noninfected control group.CONCLUSION:Z:ZCLA Mongolian gerbils are susceptible to human HEV. 展开更多
关键词 HEPATITIS E VIRUS MONGOLIAN GERBILS INFECTION Inte
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Clinical and molecular characteristics of East Asian patients with von Hippel–Lindau syndrome 被引量:3
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作者 Meihua Wong Ying-Hsia Chu +4 位作者 Hwei Ling Tan Hideharu Bessho Joanne Ngeow Tiffany Tang Min-Han Tan 《Chinese Journal of Cancer》 SCIE CAS CSCD 2016年第9期441-446,共6页
Background: Von Hippel–Lindau(VHL) syndrome is a dominantly inherited multisystem cancer syndrome caused by a heterozygous mutation in the VHL tumor suppressor gene. Previous studies suggested that similar population... Background: Von Hippel–Lindau(VHL) syndrome is a dominantly inherited multisystem cancer syndrome caused by a heterozygous mutation in the VHL tumor suppressor gene. Previous studies suggested that similar populations of Caucasian and Japanese patients have similar genotype or phenotype characteristics. In this comprehensive study of East Asian patients, we investigated the genetic and clinical characteristics of patients with VHL syndrome.Methods: To create a registry of clinical characteristics and mutations reported in East Asian patients with VHL syndrome, we conducted a comprehensive review of English language and non?English language articles identi?fied through a literature search. Publications in Japanese or Chinese language were read by native speakers of the language, who then performed the data extraction.Results: Of 237 East Asian patients with VHL syndrome, 154 unique kindreds were identified for analysis. Analyzed by kindred, missense mutations were the most common(40.9%, 63/154), followed by large/complete deletions(32.5%, 50/154) and nonsense mutations(11.7%, 18/154). Compared with a previously reported study of both East Asian and non?East Asian patients, we found several key differences. First, missense and frameshift mutations in the VHL gene occurred less commonly in our population of East Asian patients(40.9% vs. 52.0%; P = 0.012 and 8.4% vs. 13.0%; P < 0.001, respectively). Second, large/complete deletions were more common in our population of East Asian patients(32.5% vs. 10.5%; P < 0.001). Third, phenotypically, we observed that, in our population of East Asian patients with VHL syndrome, the incidence of retinal capillary hemangioblastoma was lower, whereas the incidence of renal cell carcinoma was higher.Conclusions: Evidence suggests that the genotypic and phenotypic characteristics of East Asian patients with VHL syndrome differ from other populations. This should be considered when making screening recommendations for VHL syndrome in Asia. 展开更多
关键词 临床特征 综合征 分子特征 东亚 患者 基因突变 肿瘤抑制基因 表型特征
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Expression of a New hemA Gene from Agrobacterium radiobacter in Escherichia coli for 5-Aminolevulinate Production 被引量:4
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作者 LIU Xiaoxia(刘晓侠) +5 位作者 LIN Jianping(林建平) QIN Gang(秦钢) CEN Peilin(岑沛霖) 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第4期522-528,共7页
A new hemA gene encoding 5-aminolevulinate (ALA) synthase was cloned from Agrobacterium ra- diobacter zju-0121. The ALA synthase catalyzes the pyridoxal phosphate-dependent condensation of succinyl coen- zyme A (succi... A new hemA gene encoding 5-aminolevulinate (ALA) synthase was cloned from Agrobacterium ra- diobacter zju-0121. The ALA synthase catalyzes the pyridoxal phosphate-dependent condensation of succinyl coen- zyme A (succinyl-CoA) and glycine to produce ALA. Four plasmids carrying the A, radiobacter hemA gene were transformed into different E. coli strains. The effects of both genetic and physiological factors on the expression of ALA synthase and ALA production were studied. The results indicated that the final intracellular activity of ALA synthase and the production of ALA in different expression systems varied largely. Among them, the recombinant E. coli BL21 (DE3) harboring the expression plasmid pET28-A. R-hemA was the most suitable one. The effects of isopropyl-β-D-thiogalactopyranoside (IPTG) addition time, IPTG concentration, culture temperature and the initial concentration of precursors and glucose on the ALA production were also evaluated. The expressed ALA synthase accounted for about 23.7% of the intracellular soluble protein. The highest specific activity of ALA syn- thase was 13.8nmol·min-1·mg-1 of intracellular soluble protein. In the batch culture of the recombinant E. coli, the extracellular ALA concentration reached 0.9 g·L-1. 展开更多
关键词 5-aminolevulinate (ALA) ALA synthase metabolic engineering
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Mutagenesis and Screening of High Yield Xylanase Production Strain of Aspergillus usamii by Microwave Irradiation 被引量:4
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作者 李永泉 陈时飞 岑沛霖 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第5期594-597,共4页
A high yield xylanase producing strain, A. usamii L336-23, was screened out from its parent strain A.usamii L336 after microwave irradiation. Its productivity of xylanase activity increased by 35.7% from 21000μu·... A high yield xylanase producing strain, A. usamii L336-23, was screened out from its parent strain A.usamii L336 after microwave irradiation. Its productivity of xylanase activity increased by 35.7% from 21000μu·ml-1 to 28500μu·ml-1 and was stable after frequent subcultures and storage for more than two months. The mechanism of microwave mutation was also discussed. 展开更多
关键词 microwave irradiation Aspergilles usamii XYLANASE
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Type-dependent differential expression of neuropeptide Y in chicken hypothalamus (Gallus domesticus) 被引量:3
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作者 CHEN Gui-qian HU Xiu-fang +7 位作者 SUGAHARA Kunio CHEN Ji-shuang SONG Xue-mei ZHENG Hui-chao JIANG Yong-qing HUANG Xin JIANG Jun-fang ZHOU Wei-dong 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第11期839-844,共6页
Neuropeptide Y (NPY) is one of the most important orexigenic agents in central regulation of feeding behavior, body weight and energy homeostasis in domestic chickens. To examine differences in the hypothalamic NPY ... Neuropeptide Y (NPY) is one of the most important orexigenic agents in central regulation of feeding behavior, body weight and energy homeostasis in domestic chickens. To examine differences in the hypothalamic NPY between layer-type and meat-type of chickens, which are two divergent kinds of the domestic chickens in feeding behavior and body weight, we detected mRNA levels of NPY in hypothalamic infundibular nucleus (IN), paraventricular nucleus (PVN) and lateral hypothalamic area (LHA) of these two types of chickens using one-step real time RT-PCR. The meat-type chicken had more food daily (about 1.7 folds) and greater body weights (about 1.5 folds) and brain weights than the layer-type chicken at the age of 14 d. In the meat-type of chicken, NPY mRNA levels of the IN and PVN were significantly greater than those of the LHA, and were not significantly different between the lN and PVN. However, in the layer-type of chicken, NPY mRNA levels were significantly greater in the IN than those in the LHA and PVN, and were not significantly different between the PVN and LHA. In all these hypothalamic regions the layer-type of chicken had significantly higher NPY mRNA levels than the meat-type chicken did. These results suggest the expression of NPY in the hypothalamus has a type-dependent pattern in domestic chickens. 展开更多
关键词 Neuropeptide Y (NPY) HYPOTHALAMUS Message RNA (mRNA) Meat-type chicken Layer-type chicken
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A model to predict the risk of lethal nasopharyngeal necrosis after re-irradiation with intensity-modulated radiotherapy in nasopharyngeal carcinoma patients 被引量:5
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作者 Ya-Hui Yu Wei-Xiong Xia +9 位作者 Jun-Li Shi Wen-Juan Ma Yong Li Yan-Fang Ye Hu Liang Liang-Ru Ke Xing Lv Jing Yang Yan-Qun Xiang Xiang Guo 《Chinese Journal of Cancer》 SCIE CAS CSCD 2016年第11期617-624,共8页
Background:For patients with nasopharyngeal carcinoma(NPC) who undergo re-irradiation with intensity-modulated radiotherapy(IMRT),lethal nasopharyngeal necrosis(LNN) is a severe late adverse event.The purpose of this ... Background:For patients with nasopharyngeal carcinoma(NPC) who undergo re-irradiation with intensity-modulated radiotherapy(IMRT),lethal nasopharyngeal necrosis(LNN) is a severe late adverse event.The purpose of this study was to identify risk factors for LNN and develop a model to predict LNN after radical re-irradiation with IMRT in patients with recurrent NPC.Methods:Patients who underwent radical re-irradiation with IMRT for locally recurrent NPC between March 2001 and December 2011 and who had no evidence of distant metastasis were included in this study.Clinical characteristics,including recurrent carcinoma conditions and dosimetric features,were evaluated as candidate risk factors for LNN.Logistic regression analysis was used to identify independent risk factors and construct the predictive scoring model.Results:Among 228 patients enrolled in this study,204 were at risk of developing LNN based on risk analysis.Of the 204 patients treated,31(15.2%) developed LNN.Logistic regression analysis showed that female sex(P = 0.008),necrosis before re-irradiation(P = 0.008),accumulated total prescription dose to the gross tumor volume(GTV) ≥ 145.5 Gy(P = 0.043),and recurrent tumor volume >25.38 cm3(P = 0.009) were independent risk factors for LNN.A model to predict LNN was then constructed that included these four independent risk factors.Conclusions:A model that includes sex,necrosis before re-irradiation,accumulated total prescription dose to GTV,and recurrent tumor volume can effectively predict the risk of developing LNN in NPC patients who undergo radical re-irradiation with IMRT. 展开更多
关键词 Nasopharyngeal carcinoma RE-IRRADIATION Intensity-modulated radiotherapy NECROSIS
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Production of Validamycins from Crude Substrates by Streptomyces hygroscopicus in an External-loop Airlift Bioreactor with a Low Height-to-Diameter Ratio 被引量:3
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作者 郑裕国 陈小龙 +1 位作者 汪钊 沈寅初 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第1期102-107,共6页
Fermentation experiments to produce validamycins from crude substrates by Streptomyces hygroscopicus were carried out in an external-loop airlift bioreactor (0.0115 m^3 ) with a low ratio of height to diameter of the ... Fermentation experiments to produce validamycins from crude substrates by Streptomyces hygroscopicus were carried out in an external-loop airlift bioreactor (0.0115 m^3 ) with a low ratio of height to diameter of the riser of 2.9 and a ratio of riser to downcomer diameter of 6.6. The influences of gas flow rate and liquid volume on fermentation of validamycins were investigated. Comparisons of validamycin fermentation were made among the external-loop airlift bioreactor, a mechanically stirred tank bioreactor (0.010m^3 ) and shaking flasks. Under the same operation conditions including fermentation medium composition, inoculum ratio and culture temperature, the fermentation time in the external-loop airlift bioreactor (45 h) was shorter than that in the shaking flasks (100 h) and the same as that in the mechanically stirred tank bioreactor. After a total fermentation time of 45 h under optimized operation conditions, average validamycin concentration obtained in the external-loop airlift bioreactor was close to 19630 μg·ml^-1 validamycin concentration in the mechanically stirred tank bioreactor. It was demonstrated that the external-loop airlift bioreactor could substitute for the mechanically stirred tank bioreactor in production of validamycins from crude substrates with dregs by Streptomyces hygroscopicus. 展开更多
关键词 airlift bioreactor validamycins streptomyces hygroscopicus
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Submerged culture of chromium-enriched Termitomyces albuminosus 被引量:3
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作者 HUZhong-Ce ZHENG Xiao-Dong +1 位作者 CHEN Xin-Ai ZHENG Yu-Guo 《菌物学报》 CAS CSCD 北大核心 2008年第1期118-125,共8页
A species of mushroom, Termitomyces albuminosus, was cultured in liquid medium for production of chromium-enriched mycelium. The influence of chromium (Ⅲ ) on mycelial growth of T. albuminosus was investigated. An op... A species of mushroom, Termitomyces albuminosus, was cultured in liquid medium for production of chromium-enriched mycelium. The influence of chromium (Ⅲ ) on mycelial growth of T. albuminosus was investigated. An optimum medium composed of 5.6g/L yeast extract, 51.6g/L hydrolyzed rice, 2g/L KH2PO4, and 20mg/L chromium(Ⅲ ) with initial pH of 4.5 was obtained by using method of central composite design (CCD). After incubation of 84h, the maximal biomass of chromium-enriched mycelia reached 24.23g DMW(dried mycelial weight)/L with 272μg/g DMW chromium content in 500mL flasks containing 100mL medium with an inoculum of 8% on a shaker of 100r/min under an optimized cultivation condition at 28℃. 展开更多
关键词 富铬蚁巢伞 鸡菌 液体培养 培养基
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Effects of medium composition on the production of plasmid DNA vector potentially for human gene therapy 被引量:2
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作者 徐志南 沈文和 +1 位作者 陈灏 岑沛霖 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第5期396-400,共5页
Plasmid vector is increasingly applied to gene therapy or gene vaccine. The production of plasmid pCMV-AP3 for cancer gene therapy was conducted in a modified MBL medium using a recombinant E. coli BL21 system. The ef... Plasmid vector is increasingly applied to gene therapy or gene vaccine. The production of plasmid pCMV-AP3 for cancer gene therapy was conducted in a modified MBL medium using a recombinant E. coli BL21 system. The effects of different MMBL components on plasmid yield, cell mass and specific plasmid DNA productivity were evaluated on shake-flask scale. The results showed that glucose was the optimal carbon source. High plasmid yield (58.3 mg/L) was obtained when 5.0 g/L glucose was added to MMBL. Glycerol could be chosen as a complementary carbon source because of the highest specific plasmid pro- ductivity (37.9 mg DNA/g DCW). After tests of different levels of nitrogen source and inorganic phosphate, a modified MMBL medium was formulated for optimal plasmid production. Further study showed that the initial acetate addition (less than 4.0 g/L) in MMBL improved plasmid production significantly, although it inhibited cell growth. The results will be useful for large-scale plasmid production using recombinant E. coli system. 展开更多
关键词 Plasmid DNA Growth medium Gene therapy
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Purification and characterization of keratinase from a new Bacillus subtilis strain 被引量:13
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作者 Cheng-gang CAI Ji-shuang CHEN +2 位作者 Jiong-jiong QI Yun YIN Xiao-dong ZHENG 《浙江中西医结合杂志》 2008年第9期713-720,共8页
The aim of this study was to purify and characterize a keratinase produced by a new isolated Bacillus subtilis KD-N2 strain. The keratinase produced by the isolate was purified using ammonium sulphate precipitation, S... The aim of this study was to purify and characterize a keratinase produced by a new isolated Bacillus subtilis KD-N2 strain. The keratinase produced by the isolate was purified using ammonium sulphate precipitation, Sephadex G-75 and DEAE (diethylaminoethyl)-Sepharose chromatographic techniques. The purified enzyme was shown to have a molecular mass of 30.5 kDa, as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The optimum pH at 50 °C was 8.5 and the optimum temperature at pH 8.5 was 55 °C. The keratinase was partially inactivated by some metal ions, organic solvents and serine protease inhibitor phenylmethanesulfonyl fluoride (PMSF). Sodium dodecyl sulfate (SDS) and ethylene diamine tetraacetic acid (EDTA) had positive effect on the keratinase activity. Reducing agents including dithiothreitol (DTT), mercaptoethanol, L-cysteine, sodium sulphite, as well as chemicals of SDS, ammonium sulfamate and dimethylsulfoxide (DMSO) stimulated the enzyme activity upon a feather meal substrate. Besides feather keratin, the enzyme is active upon the soluble proteins ovalbumin, bovine serum albumin (BSA), casein and insoluble ones as sheep wool and human hair. Calf hair, silk and collagen could not be hydrolyzed by the keratinase. 展开更多
关键词 净化方式 角蛋白酶 枯草杆菌 硫酸铵
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Determination of Teicoplanin A2's Partition Coefficient in Different Liquid-Liquid Extraction Systems 被引量:2
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作者 陈勇 Bin Mat Hanapi +2 位作者 徐志南 金志华 岑沛霖 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期493-497,共5页
Teicoplanin is one of the macrocyclic glycopeptide antibiotics, which is active against Gram-positive bacteria, and has attracted a lot of attention in the field of chiral separation recently. In this work, the partit... Teicoplanin is one of the macrocyclic glycopeptide antibiotics, which is active against Gram-positive bacteria, and has attracted a lot of attention in the field of chiral separation recently. In this work, the partition coefficients and extraction ratio of teicoplanin in three different solvent systems were studied: conventional extraction, reactive extraction and reverse micelle extraction. With conventional solvent extraction, n-butanol demonstrated high partition coefficient for teicoplanin, but low extraction ratio because of its high solubility in water. Reactive extraction of teicoplanin showed the highest partition coefficient with almost 100% recovery in organic phase when tri-n-octylmethyl ammonium chloride (TOMAC) was used as extractant and pH value was above 5.0. A reverse micelle system, consisted of isooctane +10mmol-L-1 TOMAC +1% n-octanol, also offered high separation factor for teicoplanin. The results are beneficial for the design of teicoplanin separation and purification process. 展开更多
关键词 TEICOPLANIN partition coefficients conventional extraction reverse micelle extraction
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Oogenesis in summer females of the rice water weevil,Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae),in southern Zhejiang,China 被引量:1
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作者 SHI Sheng-wei JIANG Ming-xing +2 位作者 SHANG Han-wu LV Hui-ping CHENG Jia-an 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第1期33-38,共6页
The rice water weevil, Lissorhoptrus oryzophilus Kuschel, has two generations in southern Zhejiang, China. To determine oogenesis in first-generation females (summer females) and its relations to temperature, female... The rice water weevil, Lissorhoptrus oryzophilus Kuschel, has two generations in southern Zhejiang, China. To determine oogenesis in first-generation females (summer females) and its relations to temperature, females were collected from a rice field in early and mid-July and reared on young rice plants at 28, 31 and 34 ℃ in the laboratory. Percentage of females having oocytes, number of oocytes of different stages (stage-Ⅰ, from early previtellogenesis to middle vitellogenesis; stage-Ⅱ, late vitellogenesis; and matute-oocyte stage), and length of ovarioles were determined every 10 d of feeding. At each temperature, oogenesis took place in over 40% of females after 20-40 d of feeding, but only 0.0-3.3 stage-Ⅰ, 0.0-0.8 stage-Ⅱ and 0.0-1.1 mature oocytes were observed at each observation date. Temperature had significant effect on number of stage-Ⅰ oocytes but not on number of stage-Ⅱ and mature oocytes in early July females; temperature had no significant effect on number of oocytes of either stage in mid-July females. Conclusively, in southern Zhejiang, summer L. oryzophilus females have great potential to become reproductive on rice, but their oogenesis activity is very low, with the overall procedures little affected by temperature. 展开更多
关键词 Lissorhoptrus oryzophilus OOGENESIS Ovarian development REPRODUCTION
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