The production capability of a fermentation process is predominately determined by individual strains,which ultimately affected ultimately by interactions between the scale-dependent flow field developed within biorea...The production capability of a fermentation process is predominately determined by individual strains,which ultimately affected ultimately by interactions between the scale-dependent flow field developed within bioreactors and the physiological response of these strains.Interpreting these complicated interactions is key for better understanding the scale-up of the fermentation process.We review these two aspects and address progress in strategies for scaling up fermentation processes.A perspective on how to incorporate the multiomics big data into the scale-up strategy is presented to improve the design and operation of industrial fermentation processes.展开更多
Antimicrobial peptides(AMP)are small proteins that play critical roles in host defense against microbe invasion.Many AMPs disrupt the cellular membrane of microbe,while the mechanism of action of AMPs can be very soph...Antimicrobial peptides(AMP)are small proteins that play critical roles in host defense against microbe invasion.Many AMPs disrupt the cellular membrane of microbe,while the mechanism of action of AMPs can be very sophisticated.Solid-state NMR(SSNMR)technique is powerful in characterizing the mechanism of AMPs in vivo and in vitro.This review summarizes the recent advance of SSNMR technique in AMP mechanisms characterization.We highlight the sample preparation approaches,the SSNMR spectroscopic methods,and a number of outstanding examples of AMP mechanisms elucidated via SSNMR spectroscopy.展开更多
BACKGROUND Liver fibrosis is a formidable global medical challenge,with no effective clinical treatment currently available.Yinhuang granule(YHG)is a proprietary Chinese medicine comprising Scutellariae Radix and Loni...BACKGROUND Liver fibrosis is a formidable global medical challenge,with no effective clinical treatment currently available.Yinhuang granule(YHG)is a proprietary Chinese medicine comprising Scutellariae Radix and Lonicerae Japonicae Flos.It is frequently used for upper respiratory tract infections,pharyngitis,as well as acute and chronic tonsillitis.AIM To investigate the potential of YHG in alleviating carbon tetrachloride(CCl4)-induced liver fibrosis in mice.METHODS To induce a hepatic fibrosis model in mice,this study involved intraperitoneal injections of 2 mL/kg of CCl4 twice a week for 4 wk.Meanwhile,liver fibrosis mice in the low dose of YHG(0.4 g/kg)and high dose of YHG(0.8 g/kg)groups were orally administered YHG once a day for 4 wk.Serum alanine/aspartate aminotransferase(ALT/AST)activity and liver hydroxyproline content were detected.Sirius red and Masson's trichrome staining assay were conducted.Realtime polymerase chain reaction,western-blot and enzyme-linked immunosorbent assay were conducted.Liver glutathione content,superoxide dismutase activity level,reactive oxygen species and protein carbonylation amount were detected.RESULTS The administration of YHG ameliorated hepatocellular injury in CCl4-treated mice,as reflected by decreased serum ALT/AST activity and improved liver histological evaluation.YHG also attenuated liver fibrosis,evident through reduced liver hydroxyproline content,improvements in Sirius red and Masson's trichrome staining,and lowered serum hyaluronic acid levels.Furthermore,YHG hindered the activation of hepatic stellate cells(HSCs)and ameliorated oxidative stress injury and inflammation in liver from CCl4-treated mice.YHG prompted the nuclear accumulation of nuclear factor erythroid 2-related factor 2(Nrf2)and upregulated the expression of Nrf2-dependent downstream antioxidant genes.In addition,YHG promoted mitochondrial biogenesis in liver from CCl4-treated mice,as demonstrated by increased liver adenosine triphosphate content,mitochondrial DNA levels,and the expression of peroxisome proliferator-activated receptor gamma coactivator 1 alpha and nuclear respiratory factor 1.CONCLUSION YHG effectively attenuates CCl4-induced liver fibrosis in mice by inhibiting the activation of HSCs,reducing inflammation,alleviating liver oxidative stress damage through Nrf2 activation,and promoting liver mitochondrial biogenesis.展开更多
By using acetonitrile as the sole nitrogen source, a microbial strain with high nitrilase activity, named as Alcaligenes sp. ECU0401, was newly isolated from soil, which could enantioselectively transform racemic mand...By using acetonitrile as the sole nitrogen source, a microbial strain with high nitrilase activity, named as Alcaligenes sp. ECU0401, was newly isolated from soil, which could enantioselectively transform racemic mandelonitrile into (R)-(-)-mandelic acid, with an enantiomeric excess of 】99.9%.展开更多
To reduce the variations of the production process in penicillin cultivations, a rolling multivariate statis-tical approach based on multiway principle component analysis (MPCA) is developed and used for fault diagnos...To reduce the variations of the production process in penicillin cultivations, a rolling multivariate statis-tical approach based on multiway principle component analysis (MPCA) is developed and used for fault diagnosis of penicillin cultivations. Using the moving data windows technique, the static MPCA is extended for use in dy-namic process performance monitoring. The control chart is set up using the historical data collected from the past successful batches, thereby resulting in simplification of monitoring charts, easy tracking of the progress in each batch run, and monitoring the occurrence of the observable upsets. Data from the commercial-scale penicillin fer-mentation process are used to develop the rolling model. Using this method, faults are detected in real time and the corresponding measurements of these faults are directly made through inspection of a few simple plots (t-chart, SPE-chart, and T2-chart). Thus, the present methodology allows the process operator to actively monitor the data from several cultivations simultaneously.展开更多
The online upgrading process that combined the fast pyrolysis of biomass and catalytic cracking of bio-oil was developed to produce a high quality liquid product from the biomass.The installation consisted of a fluidi...The online upgrading process that combined the fast pyrolysis of biomass and catalytic cracking of bio-oil was developed to produce a high quality liquid product from the biomass.The installation consisted of a fluidized bed reactor for pyrolysis and a packed bed reactor for upgrading.The proper pyrolysis processing conditions with a temperature of 500℃ and a flow rate of 4m3·h-1 were determined in advance.Under such conditions,the effects of temperature and weight hourly space velocity(WHSV) on both the liquid yields and the oil qualities of the online catalytic cracking process were investigated.The results showed that such a combined process had the superiority of increasing the liquid yield and improving the product quality over the separate processes.Furthermore,when the temperature was 500℃,with a WHSV of 3h-1,the liquid yield reached the maximum and the oxygenic compounds also decreased obviously.展开更多
Expanded bed adsorption (EBA) has been widely used in industrial downstream bioprocessing,Solid matrix is the principal pillar supporting the successful application of EBA.A novel spherical ceelulose-titanium dioxide ...Expanded bed adsorption (EBA) has been widely used in industrial downstream bioprocessing,Solid matrix is the principal pillar supporting the successful application of EBA.A novel spherical ceelulose-titanium dioxide composite matrix was prepared through the method of water-in-oil suspension thermal regeneration.Its typical physical properties were wet density 1.18g.cm^-3,,diameters in the range of 100-300μm ,porosity 85.5%,and water content 72.3%.Expansion characteristics and liquid mixing performance of the matrix in expanded bed were investigated using water and 10% (by mass )glycerol solution as mobile phases,The results indicate that the custom-assembled matrix has a stable flow hydrodynamics and exhibits the same degree of liquid-phase mixing or column efficiency as the commercially available Streamline adsorbent.展开更多
Microfluidic,as the systems for using microchannel(micron-or sub-micron scale)to process or manipulate microflow,is being widely applied in enzyme biotechnology and biocatalysis.Microfluidic immobilized enzyme reactor...Microfluidic,as the systems for using microchannel(micron-or sub-micron scale)to process or manipulate microflow,is being widely applied in enzyme biotechnology and biocatalysis.Microfluidic immobilized enzyme reactor(MIER)is a tool with great value for the study of catalytic property and optimal reaction parameter in a flourishing and highly producing manner.In view of its advantages in efficiency,economy,and addressable recognition especially,MIER occupies an important position in the investigation of life science,including molecular biology,bioanalysis and biosensing,biocatalysis etc.Immobilization of enzymes can generally improve their stability,and upon most occasions,the immobilized enzyme is endowed with recyclability.In this review,the enzyme immobilization techniques applied in MIER will be discussed,followed by summarizing the novel developments in the field of MIER for biocatalysis,bioconversion and bioanalysis.The preponderances and deficiencies of the current state-of-the-art preparation ways of MIER are peculiarly discussed.In addition,the prospects of its future study are outlined.展开更多
Turbulent mixing, in particular on a small scale, aff ects the growth of microalgae by changing diff usive sublayers and regulating nutrient fluxes of cells. We tested the nutrient flux hypothesis by evaluating the ce...Turbulent mixing, in particular on a small scale, aff ects the growth of microalgae by changing diff usive sublayers and regulating nutrient fluxes of cells. We tested the nutrient flux hypothesis by evaluating the cellular stoichiometry and phosphorus storage of microalgae under dif ferent turbulent mixing conditions. A phanizomenon flos-aquae were cultivated in dif ferent stirring batch reactors with turbulent dissipation rates ranging from 0.001 51 m2/s 3 to 0.050 58 m 2/s 3, the latter being the highest range observed in natural aquatic systems. Samples were taken in the exponential growth phase and compared with samples taken when the reactor was completely stagnant. Results indicate that, within a certain range, turbulent mixing stimulates the growth of A. flos-aquae. An inhibitory ef fect on growth rate was observed at the higher range. Photosynthesis activity, in terms of maximum ef fective quantum yield of PSII(the ratio of F v/F m) and cellular chlorophyll a, did not change significantly in response to turbulence. However, Chl a/C mass ratio and C/N molar ratio, showed a unimodal response under a gradient of turbulent mixing, similar to growth rate. Moreover, we found that increases in turbulent mixing might stimulate respiration rates, which might lead to the use of polyphosphate for the synthesis of cellular constituents. More research is required to test and verify the hypothesis that turbulent mixing changes the dif fusive sublayer, regulating the nutrient flux of cells.展开更多
To track the rapidly changing temperature profiles of thermal cycling of polymerase chain reaction (PCR) accurately, an innovative feedforward variable structural proportional-integral-derivative (FVSPID) control- ler...To track the rapidly changing temperature profiles of thermal cycling of polymerase chain reaction (PCR) accurately, an innovative feedforward variable structural proportional-integral-derivative (FVSPID) control- ler was developed. Based on the step response test data of the heat block, a reduced first order model was estab- lished at different operating points. Based on the reduced model, the FVSPID controller combined a feedforward path with the variable structural proportional-integral-derivative (PID) control. The modified feedforward action provided directly the optimal predictive power for the desired setpoint to speed up the dynamic response. To coop- erate with the feedforward action, a variable structural PID was applied, where the P mode was used in the case of the largest errors to speed up response, whereas the PD mode was used in the case of larger errors to suppress over- shoot, and finally the PID mode was applied for small error conditions to eliminate the steady state offset. Experi- mental results illustrated that compared to the conventional PID controller, the FVSPID controller can not only re- duce the time taken to complete a standard PCR protocol, but also improve the accuracy of gene amplification.展开更多
Objective:To determine whether a new-born child from a family carrying a deafness gene needs cochlear implantation to avoid dysphonia by screening and sequencing a deafness-related gene.Results:Both screening and sequ...Objective:To determine whether a new-born child from a family carrying a deafness gene needs cochlear implantation to avoid dysphonia by screening and sequencing a deafness-related gene.Results:Both screening and sequencing results confirmed that the new born child had a normal GJB2 gene despite the fact that she has a brother suffering from hearing loss triggered by an allelic GJB2 c.176 del 16 mutation.We cloned the GJB2 genes derived from their respective blood genomic DNA into GFP fused plasmids and transfected those plasmids into the 293 T cell line to test for gene function.While the mutated GJB2gene(GJB2 c.176 del 16) of her deaf brother was found to be unable to form the gap junction structure between two adjacent cells,the baby girl's GJB2 gene ran into no such problems.Conclusion:The screening and sequencing as well as the GJB2 gene function tests invariably showed results consistent with the ABR tested hearing phenotype,which means that the child,with a normal wild type GJB2 gene,does not need early intervention to prevent her from developing hearing loss and dysphonia at a later stage in life.展开更多
The massive consumption of fossil energy force s people to find new source s of energy.Syngas fermentation has become a hot research field as its high potential in renewable energy production and sustainable developme...The massive consumption of fossil energy force s people to find new source s of energy.Syngas fermentation has become a hot research field as its high potential in renewable energy production and sustainable development.In this study,trophic anaerobic acetogen Morella thermoacetica was successfully immobilized by calcium alginate embedding method.The ability of the immobilized cells on production of acetic acid through syngas fermentation was compared in both airlift and bubble column bioreactors.The bubble column bioreactor was selected as the better type of bioreactor.The production of acetic acid reached 32.3 g·L^(-1) in bubble column bioreactor with a space-time yield of 2.13 g·L^(-1)·d^(-1).The immobilized acetogen could be efficiently reused without significant lag period,even if exposed to air for a short time.A semi-continuous syngas fermentation was performed using immobilized cells,with an average space-time acetic acid yield of 3.20 g·L^(-1)·d^(-1).After 30 days of fermentation,no significant decrea se of the acetic acid production rate was observed.展开更多
Volatile organic compounds (VOCs) are the major group of indoor air pollutants, which significantly impact indoor air quality (IAQ) and influence human health. Photocatalytic oxidation (PCO) is a cost-effective techno...Volatile organic compounds (VOCs) are the major group of indoor air pollutants, which significantly impact indoor air quality (IAQ) and influence human health. Photocatalytic oxidation (PCO) is a cost-effective technology for VOCs removal, compared with adsorption, biofiltration, or thermal catalysis method. Development of active photocatalyst systems is crucial for the PCO reaction. In this paper, the catalyst systems for photocatalysis under UV and visible light were discussed and the kinetics of photocatalytic oxidation was presented in order that some key influencing factors (relative huminity, light intensity, initial contaminant concentration and mass of catalyst) had also been studied. In addition, the future research directions were also presented in this paper.展开更多
Optically pure(R)-γ-and(R)-δ-lactones can be prepared by intramolecular cyclization of chiral hydroxy acids/esters reduced asymmetrically from γ-and δ-keto acids/esters using Saccharomyces cerevisiae(S.cerevisiae)...Optically pure(R)-γ-and(R)-δ-lactones can be prepared by intramolecular cyclization of chiral hydroxy acids/esters reduced asymmetrically from γ-and δ-keto acids/esters using Saccharomyces cerevisiae(S.cerevisiae) as a whole-cell biocatalyst.However,some of the enzymes catalyzing these reactions in S.cerevisiae are still unknown up to date.In this report,two carbonyl reductases,OdCRl and OdCR2,were successfully discovered,and cloned from S.cerevisiae using a genome-mining approach,and overexpressed in Escherichia coli(E.coli).Compared with OdCR1,OdCR2 can reduce 4-oxodecanoic acid and 5-oxodecanoic acid asymmetrically with higher stereoselectivity,generating(R)-γ-decalactone(99% ee) and(R)-δ-decalactone(98% ee) in 85% and 92%yields,respectively.This is the first report of native enzymes from S.cerevisiae for the enzymatic synthesis of chiral γ-and δ-lactones which is of wide uses in food and cosmetic industries.展开更多
The lipase activities in the three main Chinese castor bean varieties [ZiBi 05 (ZB 5),TongBi 06 (TB 6),JinBi 02 (JB 2)] were investigated.Two lipases were found in extracts from the endosperms of all the three varieti...The lipase activities in the three main Chinese castor bean varieties [ZiBi 05 (ZB 5),TongBi 06 (TB 6),JinBi 02 (JB 2)] were investigated.Two lipases were found in extracts from the endosperms of all the three varieties.One lipase is located in the lipid bodies,showing higher activity at pH 4.5 and exhibiting the highest activity at day 1 of germination.The other lipase is located in the particulates,showing higher activity at pH 9.5 and particularly active at day 4 of germination.The lipid bodies from ZB 5 show the highest lipase activity at day 1 and pH 4.5 among the three varieties during the 8 d of germination.The acid lipase located in the lipid bodies of ZB 5 of germination 1 d was purified to homogeneity by DEAE-sepharose CL-6B and butyl-sepharose CL-4B chromatography after isolation,delipidation and solubilization,with a purification factor of 16.1 and overall activity recovery of 17.7%.The characterizations (such as optimum pH,pH stability,optimum temperature,thermal stability,effect of metal ions,organic solvents stability,substrate specificity) of the purified acid lipase were conducted in detail.A combination of the characterized properties may make this enzyme a useful biocatalyst for industrial application.展开更多
Objective: To explore the change of chemosensitivity of gallbladder cancer cells pre-treated with somatostatin. Methods: Twenty-four hours after somatostatin treatment, gradient concentrated Doxorubicin was added and ...Objective: To explore the change of chemosensitivity of gallbladder cancer cells pre-treated with somatostatin. Methods: Twenty-four hours after somatostatin treatment, gradient concentrated Doxorubicin was added and growth curve of gallbladder cancer cells was investigated to measure IC50, i.e., concentration of Doxorubicin at 50% cell viability. Results: Somatostatin ccould induce gallbladder cancer cell growth arrest in S phase. Inhibition of growth of cancer cell line was detected by Doxorubicin concentration- dependently (P<0.05). IC50 value was significantly lower by combined-treating with somatostatin and Doxorubicin compared with by Doxorubicin alone (P<0.05). Conclusion: Somatostatin could increase the cytotoxic effect of Doxorubicin on gallbladder cancer cell by modulating its cell cycle.展开更多
AIM: To establish a multiple detection method based on comparative polymerase chain reaction (cPCR) and ligase detection reaction (LDR)/ligase chain reaction (LCR) to quantify the intestinal bacterial components. METH...AIM: To establish a multiple detection method based on comparative polymerase chain reaction (cPCR) and ligase detection reaction (LDR)/ligase chain reaction (LCR) to quantify the intestinal bacterial components. METHODS: Comparative quantification of 16S rDNAs from different intestinal bacterial components was used to quantify multiple intestinal bacteria. The 16S rDNAs of different bacteria were amplified simultaneously by cPCR. The LDR/LCR was examined to actualize the genotyping and quantification. Two beneficial (Bifidobacterium , Lactobacillus ) and three conditionally pathogenic bacteria (Enterococcus , Enterobacterium and Eubacterium ) were used in this detection. With cloned standard bacterial 16S rDNAs, standard curves were prepared to validate the quantitative relations between the ratio of original concentrations of two templates and the ratio ofthe fluorescence signals of their final ligation products. The internal controls were added to monitor the whole detection flow. The quantity ratio between two bacteria was tested. RESULTS: cPCR and LDR revealed obvious linear correlations with standard DNAs, but cPCR and LCR did not. In the sample test, the distributions of the quantity ratio between each two bacterial species were obtained. There were significant differences among these distributions in the total samples. But these distributions of quantity ratio of each two bacteria remained stable among groups divided by age or sex. CONCLUSION: The detection method in this study can be used to conduct multiple intestinal bacteria genotyping and quantification, and to monitor the human intestinal health status as well.展开更多
Electrospinning technique was used for the fabrication of poly( vinyl alcohol)( PVA) / regenerated silk fibroin( SF)composite nanofibers,loaded with ciprofloxacin HCl( CipH Cl) as a wound dressing.Electrospun PVA / SF...Electrospinning technique was used for the fabrication of poly( vinyl alcohol)( PVA) / regenerated silk fibroin( SF)composite nanofibers,loaded with ciprofloxacin HCl( CipH Cl) as a wound dressing.Electrospun PVA / SF / CipH Cl composite nanofibers were stabilized against dissolving in water by heating in an oven at155 ℃ for 5 min.Incorporation of CipH Cl into electrospun nanofibers was confirmed by SEM and FT-IR spectra.Further the mechanical properties test illustrated that the addition of CipH Cl enhanced the mechanical properties of PVA and PVA / SF nanofibers.The antibacterial activities against Escherichia coli( E.coli)( gram-negative) and Staphylococcus aureus( S.aureus)( gram-positive) organisms were evaluated by disk diffusion method;and results suggested that electrospun PVA / CipH Cl and PVA / SF /CipH Cl composite nanofibers showed a remarkable antibacterial activity.展开更多
基金The authors would like to acknowledge the Projects 21776082 and 21978085 supported by National Natural Science Foundation of ChinaProject 22221818014 supported by the Fundamental Research Funds for the Central Universities.
文摘The production capability of a fermentation process is predominately determined by individual strains,which ultimately affected ultimately by interactions between the scale-dependent flow field developed within bioreactors and the physiological response of these strains.Interpreting these complicated interactions is key for better understanding the scale-up of the fermentation process.We review these two aspects and address progress in strategies for scaling up fermentation processes.A perspective on how to incorporate the multiomics big data into the scale-up strategy is presented to improve the design and operation of industrial fermentation processes.
基金supported by the National Key Research and Development Program of the Ministry of Science and Technology,People's Republic of China(contract number 2016YFA0501203)the National Natural Science Foundation of China(21874004,31470727)the Interdisciplinary Medicine Seed Fund of Peking University,and the Fundamental Research Funds for the Central University.
文摘Antimicrobial peptides(AMP)are small proteins that play critical roles in host defense against microbe invasion.Many AMPs disrupt the cellular membrane of microbe,while the mechanism of action of AMPs can be very sophisticated.Solid-state NMR(SSNMR)technique is powerful in characterizing the mechanism of AMPs in vivo and in vitro.This review summarizes the recent advance of SSNMR technique in AMP mechanisms characterization.We highlight the sample preparation approaches,the SSNMR spectroscopic methods,and a number of outstanding examples of AMP mechanisms elucidated via SSNMR spectroscopy.
基金Supported by Preclinical Study of A New Chinese Herbal Medicine for the Treatment of Ascites of Liver Cirrhosis(Spleen and Kidney Yang Deficiency Type)with the Clinical Formula of Qigui Xiaogu Cataplasm,No.23S21900100Traditional Chinese Medicine/Chinese and Western Medicine Advantage Specialty Construction Specialty for Department of Hepatology,No.YW(2023-2024)-01-03+2 种基金National Natural Science Foundation of China,No 82074386Construction of Special Disease Alliance of Traditional Chinese Medicine in East China Area and Municipal Level,Shanghai Special Disease Alliance of Traditional Chinese Medicine for Liver Cirrhosis Ascites(Water sickness),and Clinical Research Plan of SHDC,No.SHDC2020CR3095BNational Funded Postdoctoral Researcher Program,No.GZB20230448.
文摘BACKGROUND Liver fibrosis is a formidable global medical challenge,with no effective clinical treatment currently available.Yinhuang granule(YHG)is a proprietary Chinese medicine comprising Scutellariae Radix and Lonicerae Japonicae Flos.It is frequently used for upper respiratory tract infections,pharyngitis,as well as acute and chronic tonsillitis.AIM To investigate the potential of YHG in alleviating carbon tetrachloride(CCl4)-induced liver fibrosis in mice.METHODS To induce a hepatic fibrosis model in mice,this study involved intraperitoneal injections of 2 mL/kg of CCl4 twice a week for 4 wk.Meanwhile,liver fibrosis mice in the low dose of YHG(0.4 g/kg)and high dose of YHG(0.8 g/kg)groups were orally administered YHG once a day for 4 wk.Serum alanine/aspartate aminotransferase(ALT/AST)activity and liver hydroxyproline content were detected.Sirius red and Masson's trichrome staining assay were conducted.Realtime polymerase chain reaction,western-blot and enzyme-linked immunosorbent assay were conducted.Liver glutathione content,superoxide dismutase activity level,reactive oxygen species and protein carbonylation amount were detected.RESULTS The administration of YHG ameliorated hepatocellular injury in CCl4-treated mice,as reflected by decreased serum ALT/AST activity and improved liver histological evaluation.YHG also attenuated liver fibrosis,evident through reduced liver hydroxyproline content,improvements in Sirius red and Masson's trichrome staining,and lowered serum hyaluronic acid levels.Furthermore,YHG hindered the activation of hepatic stellate cells(HSCs)and ameliorated oxidative stress injury and inflammation in liver from CCl4-treated mice.YHG prompted the nuclear accumulation of nuclear factor erythroid 2-related factor 2(Nrf2)and upregulated the expression of Nrf2-dependent downstream antioxidant genes.In addition,YHG promoted mitochondrial biogenesis in liver from CCl4-treated mice,as demonstrated by increased liver adenosine triphosphate content,mitochondrial DNA levels,and the expression of peroxisome proliferator-activated receptor gamma coactivator 1 alpha and nuclear respiratory factor 1.CONCLUSION YHG effectively attenuates CCl4-induced liver fibrosis in mice by inhibiting the activation of HSCs,reducing inflammation,alleviating liver oxidative stress damage through Nrf2 activation,and promoting liver mitochondrial biogenesis.
文摘By using acetonitrile as the sole nitrogen source, a microbial strain with high nitrilase activity, named as Alcaligenes sp. ECU0401, was newly isolated from soil, which could enantioselectively transform racemic mandelonitrile into (R)-(-)-mandelic acid, with an enantiomeric excess of 】99.9%.
基金Supported by the National Natural Science Foundation of China (No.60574038).
文摘To reduce the variations of the production process in penicillin cultivations, a rolling multivariate statis-tical approach based on multiway principle component analysis (MPCA) is developed and used for fault diagnosis of penicillin cultivations. Using the moving data windows technique, the static MPCA is extended for use in dy-namic process performance monitoring. The control chart is set up using the historical data collected from the past successful batches, thereby resulting in simplification of monitoring charts, easy tracking of the progress in each batch run, and monitoring the occurrence of the observable upsets. Data from the commercial-scale penicillin fer-mentation process are used to develop the rolling model. Using this method, faults are detected in real time and the corresponding measurements of these faults are directly made through inspection of a few simple plots (t-chart, SPE-chart, and T2-chart). Thus, the present methodology allows the process operator to actively monitor the data from several cultivations simultaneously.
基金Major State Basic Research Development Program of China(973 Program,2007cb210206)
文摘The online upgrading process that combined the fast pyrolysis of biomass and catalytic cracking of bio-oil was developed to produce a high quality liquid product from the biomass.The installation consisted of a fluidized bed reactor for pyrolysis and a packed bed reactor for upgrading.The proper pyrolysis processing conditions with a temperature of 500℃ and a flow rate of 4m3·h-1 were determined in advance.Under such conditions,the effects of temperature and weight hourly space velocity(WHSV) on both the liquid yields and the oil qualities of the online catalytic cracking process were investigated.The results showed that such a combined process had the superiority of increasing the liquid yield and improving the product quality over the separate processes.Furthermore,when the temperature was 500℃,with a WHSV of 3h-1,the liquid yield reached the maximum and the oxygenic compounds also decreased obviously.
基金Supported by the National Natural Science Foundation of China(No.20076042,No.20206029)and the Scientific Research Foundation of the State Education Ministry for the Returned Overseas Chinese Scholars(No.2002-247).
文摘Expanded bed adsorption (EBA) has been widely used in industrial downstream bioprocessing,Solid matrix is the principal pillar supporting the successful application of EBA.A novel spherical ceelulose-titanium dioxide composite matrix was prepared through the method of water-in-oil suspension thermal regeneration.Its typical physical properties were wet density 1.18g.cm^-3,,diameters in the range of 100-300μm ,porosity 85.5%,and water content 72.3%.Expansion characteristics and liquid mixing performance of the matrix in expanded bed were investigated using water and 10% (by mass )glycerol solution as mobile phases,The results indicate that the custom-assembled matrix has a stable flow hydrodynamics and exhibits the same degree of liquid-phase mixing or column efficiency as the commercially available Streamline adsorbent.
文摘Microfluidic,as the systems for using microchannel(micron-or sub-micron scale)to process or manipulate microflow,is being widely applied in enzyme biotechnology and biocatalysis.Microfluidic immobilized enzyme reactor(MIER)is a tool with great value for the study of catalytic property and optimal reaction parameter in a flourishing and highly producing manner.In view of its advantages in efficiency,economy,and addressable recognition especially,MIER occupies an important position in the investigation of life science,including molecular biology,bioanalysis and biosensing,biocatalysis etc.Immobilization of enzymes can generally improve their stability,and upon most occasions,the immobilized enzyme is endowed with recyclability.In this review,the enzyme immobilization techniques applied in MIER will be discussed,followed by summarizing the novel developments in the field of MIER for biocatalysis,bioconversion and bioanalysis.The preponderances and deficiencies of the current state-of-the-art preparation ways of MIER are peculiarly discussed.In addition,the prospects of its future study are outlined.
基金Supported by the National Natural Science Foundation of China(Nos.51309220,51679226)the National Key SandT Project on Water Pollution Control and Treatment(Nos.2014ZX07104-006,2015ZX07103-007)the Western Action Program funded by the Chinese Academy of Sciences(No.KZCX2-XB3-14)
文摘Turbulent mixing, in particular on a small scale, aff ects the growth of microalgae by changing diff usive sublayers and regulating nutrient fluxes of cells. We tested the nutrient flux hypothesis by evaluating the cellular stoichiometry and phosphorus storage of microalgae under dif ferent turbulent mixing conditions. A phanizomenon flos-aquae were cultivated in dif ferent stirring batch reactors with turbulent dissipation rates ranging from 0.001 51 m2/s 3 to 0.050 58 m 2/s 3, the latter being the highest range observed in natural aquatic systems. Samples were taken in the exponential growth phase and compared with samples taken when the reactor was completely stagnant. Results indicate that, within a certain range, turbulent mixing stimulates the growth of A. flos-aquae. An inhibitory ef fect on growth rate was observed at the higher range. Photosynthesis activity, in terms of maximum ef fective quantum yield of PSII(the ratio of F v/F m) and cellular chlorophyll a, did not change significantly in response to turbulence. However, Chl a/C mass ratio and C/N molar ratio, showed a unimodal response under a gradient of turbulent mixing, similar to growth rate. Moreover, we found that increases in turbulent mixing might stimulate respiration rates, which might lead to the use of polyphosphate for the synthesis of cellular constituents. More research is required to test and verify the hypothesis that turbulent mixing changes the dif fusive sublayer, regulating the nutrient flux of cells.
基金Supported by the National Natural Science Foundation of China (No.60574038) and the Open Project Program of the State KeyLaboratory of Bioreactor Engineering/ECUST.
文摘To track the rapidly changing temperature profiles of thermal cycling of polymerase chain reaction (PCR) accurately, an innovative feedforward variable structural proportional-integral-derivative (FVSPID) control- ler was developed. Based on the step response test data of the heat block, a reduced first order model was estab- lished at different operating points. Based on the reduced model, the FVSPID controller combined a feedforward path with the variable structural proportional-integral-derivative (PID) control. The modified feedforward action provided directly the optimal predictive power for the desired setpoint to speed up the dynamic response. To coop- erate with the feedforward action, a variable structural PID was applied, where the P mode was used in the case of the largest errors to speed up response, whereas the PD mode was used in the case of larger errors to suppress over- shoot, and finally the PID mode was applied for small error conditions to eliminate the steady state offset. Experi- mental results illustrated that compared to the conventional PID controller, the FVSPID controller can not only re- duce the time taken to complete a standard PCR protocol, but also improve the accuracy of gene amplification.
基金supported by grants from National Natural Science Foundation of China (81470684)Clinical Special Fund of Jiangsu Province (b12014032)+4 种基金Postdoctoral Science Foundation of China (2015M571818)Six Major Categories Talent (2014-WSN-043,2011-WS-074)Innovation and Entrepreneurship Training Program for College Students in Jiangsu Province (201510313003Z,201510313003,KYLX14-1455)Clinic Medical Special Foundation of Jiangsu Province (b12014032)Project of natural science research area of Jiangsu Province (16KJB320016)
文摘Objective:To determine whether a new-born child from a family carrying a deafness gene needs cochlear implantation to avoid dysphonia by screening and sequencing a deafness-related gene.Results:Both screening and sequencing results confirmed that the new born child had a normal GJB2 gene despite the fact that she has a brother suffering from hearing loss triggered by an allelic GJB2 c.176 del 16 mutation.We cloned the GJB2 genes derived from their respective blood genomic DNA into GFP fused plasmids and transfected those plasmids into the 293 T cell line to test for gene function.While the mutated GJB2gene(GJB2 c.176 del 16) of her deaf brother was found to be unable to form the gap junction structure between two adjacent cells,the baby girl's GJB2 gene ran into no such problems.Conclusion:The screening and sequencing as well as the GJB2 gene function tests invariably showed results consistent with the ABR tested hearing phenotype,which means that the child,with a normal wild type GJB2 gene,does not need early intervention to prevent her from developing hearing loss and dysphonia at a later stage in life.
基金supported by the National Key Research and Development Program of China (2019YFA0905000)the National Natural Science Foundation of China (21536004, 21922804, 21776085, and 21871085)the Fundamental Research Funds for the Central Universities (22221818014)。
文摘The massive consumption of fossil energy force s people to find new source s of energy.Syngas fermentation has become a hot research field as its high potential in renewable energy production and sustainable development.In this study,trophic anaerobic acetogen Morella thermoacetica was successfully immobilized by calcium alginate embedding method.The ability of the immobilized cells on production of acetic acid through syngas fermentation was compared in both airlift and bubble column bioreactors.The bubble column bioreactor was selected as the better type of bioreactor.The production of acetic acid reached 32.3 g·L^(-1) in bubble column bioreactor with a space-time yield of 2.13 g·L^(-1)·d^(-1).The immobilized acetogen could be efficiently reused without significant lag period,even if exposed to air for a short time.A semi-continuous syngas fermentation was performed using immobilized cells,with an average space-time acetic acid yield of 3.20 g·L^(-1)·d^(-1).After 30 days of fermentation,no significant decrea se of the acetic acid production rate was observed.
文摘Volatile organic compounds (VOCs) are the major group of indoor air pollutants, which significantly impact indoor air quality (IAQ) and influence human health. Photocatalytic oxidation (PCO) is a cost-effective technology for VOCs removal, compared with adsorption, biofiltration, or thermal catalysis method. Development of active photocatalyst systems is crucial for the PCO reaction. In this paper, the catalyst systems for photocatalysis under UV and visible light were discussed and the kinetics of photocatalytic oxidation was presented in order that some key influencing factors (relative huminity, light intensity, initial contaminant concentration and mass of catalyst) had also been studied. In addition, the future research directions were also presented in this paper.
基金financially sponsored by the National Key Research and Development Program of China (2016YFA0204300, 2019YFA09005000)the National Natural Science Foundation of China (21536004, 21776085, 21871085)+2 种基金the Natural Science Foundation of Shanghai (18ZR1409900)Key Project of the Shanghai Science and Technology Committee (18DZ1112703)the Fundamental Research Funds for the Central Universities (WF1714026)。
文摘Optically pure(R)-γ-and(R)-δ-lactones can be prepared by intramolecular cyclization of chiral hydroxy acids/esters reduced asymmetrically from γ-and δ-keto acids/esters using Saccharomyces cerevisiae(S.cerevisiae) as a whole-cell biocatalyst.However,some of the enzymes catalyzing these reactions in S.cerevisiae are still unknown up to date.In this report,two carbonyl reductases,OdCRl and OdCR2,were successfully discovered,and cloned from S.cerevisiae using a genome-mining approach,and overexpressed in Escherichia coli(E.coli).Compared with OdCR1,OdCR2 can reduce 4-oxodecanoic acid and 5-oxodecanoic acid asymmetrically with higher stereoselectivity,generating(R)-γ-decalactone(99% ee) and(R)-δ-decalactone(98% ee) in 85% and 92%yields,respectively.This is the first report of native enzymes from S.cerevisiae for the enzymatic synthesis of chiral γ-and δ-lactones which is of wide uses in food and cosmetic industries.
基金supported by the Key Laboratory of Renewable Energy and Gas Hydrate,Chinese Academy of Sciences (Grant No.KLREGH0807k4)the Shanghai Postdoctoral Scientific Program (Grant No.09R21421400),the China Postdoctoral Science Foundation (Grant No.20090450670)the National Special Foundation for State Key Laboratory of Bioreactor Engineering(Grant No.2060204)
文摘The lipase activities in the three main Chinese castor bean varieties [ZiBi 05 (ZB 5),TongBi 06 (TB 6),JinBi 02 (JB 2)] were investigated.Two lipases were found in extracts from the endosperms of all the three varieties.One lipase is located in the lipid bodies,showing higher activity at pH 4.5 and exhibiting the highest activity at day 1 of germination.The other lipase is located in the particulates,showing higher activity at pH 9.5 and particularly active at day 4 of germination.The lipid bodies from ZB 5 show the highest lipase activity at day 1 and pH 4.5 among the three varieties during the 8 d of germination.The acid lipase located in the lipid bodies of ZB 5 of germination 1 d was purified to homogeneity by DEAE-sepharose CL-6B and butyl-sepharose CL-4B chromatography after isolation,delipidation and solubilization,with a purification factor of 16.1 and overall activity recovery of 17.7%.The characterizations (such as optimum pH,pH stability,optimum temperature,thermal stability,effect of metal ions,organic solvents stability,substrate specificity) of the purified acid lipase were conducted in detail.A combination of the characterized properties may make this enzyme a useful biocatalyst for industrial application.
文摘Objective: To explore the change of chemosensitivity of gallbladder cancer cells pre-treated with somatostatin. Methods: Twenty-four hours after somatostatin treatment, gradient concentrated Doxorubicin was added and growth curve of gallbladder cancer cells was investigated to measure IC50, i.e., concentration of Doxorubicin at 50% cell viability. Results: Somatostatin ccould induce gallbladder cancer cell growth arrest in S phase. Inhibition of growth of cancer cell line was detected by Doxorubicin concentration- dependently (P<0.05). IC50 value was significantly lower by combined-treating with somatostatin and Doxorubicin compared with by Doxorubicin alone (P<0.05). Conclusion: Somatostatin could increase the cytotoxic effect of Doxorubicin on gallbladder cancer cell by modulating its cell cycle.
文摘AIM: To establish a multiple detection method based on comparative polymerase chain reaction (cPCR) and ligase detection reaction (LDR)/ligase chain reaction (LCR) to quantify the intestinal bacterial components. METHODS: Comparative quantification of 16S rDNAs from different intestinal bacterial components was used to quantify multiple intestinal bacteria. The 16S rDNAs of different bacteria were amplified simultaneously by cPCR. The LDR/LCR was examined to actualize the genotyping and quantification. Two beneficial (Bifidobacterium , Lactobacillus ) and three conditionally pathogenic bacteria (Enterococcus , Enterobacterium and Eubacterium ) were used in this detection. With cloned standard bacterial 16S rDNAs, standard curves were prepared to validate the quantitative relations between the ratio of original concentrations of two templates and the ratio ofthe fluorescence signals of their final ligation products. The internal controls were added to monitor the whole detection flow. The quantity ratio between two bacteria was tested. RESULTS: cPCR and LDR revealed obvious linear correlations with standard DNAs, but cPCR and LCR did not. In the sample test, the distributions of the quantity ratio between each two bacterial species were obtained. There were significant differences among these distributions in the total samples. But these distributions of quantity ratio of each two bacteria remained stable among groups divided by age or sex. CONCLUSION: The detection method in this study can be used to conduct multiple intestinal bacteria genotyping and quantification, and to monitor the human intestinal health status as well.
基金"111 Project" Biomedical Textile Materials Science and Technology,China(No.B07024)National Natural Science Foundations of China(Nos.31070871,31271035)+1 种基金Science and Technology Commission of Shanghai Municipality,China(No.11nm0506200)Ph.D.Programs Foundation of Ministry of Education of China(No.20130075110005)
文摘Electrospinning technique was used for the fabrication of poly( vinyl alcohol)( PVA) / regenerated silk fibroin( SF)composite nanofibers,loaded with ciprofloxacin HCl( CipH Cl) as a wound dressing.Electrospun PVA / SF / CipH Cl composite nanofibers were stabilized against dissolving in water by heating in an oven at155 ℃ for 5 min.Incorporation of CipH Cl into electrospun nanofibers was confirmed by SEM and FT-IR spectra.Further the mechanical properties test illustrated that the addition of CipH Cl enhanced the mechanical properties of PVA and PVA / SF nanofibers.The antibacterial activities against Escherichia coli( E.coli)( gram-negative) and Staphylococcus aureus( S.aureus)( gram-positive) organisms were evaluated by disk diffusion method;and results suggested that electrospun PVA / CipH Cl and PVA / SF /CipH Cl composite nanofibers showed a remarkable antibacterial activity.