The present letter to the editor is related to the study titled‘Angiotensin-converting enzyme 2 improves liver fibrosis in mice by regulating autophagy of hepatic stellate cells’.Angiotensin-converting enzyme 2 can ...The present letter to the editor is related to the study titled‘Angiotensin-converting enzyme 2 improves liver fibrosis in mice by regulating autophagy of hepatic stellate cells’.Angiotensin-converting enzyme 2 can alleviate liver fibrosis by regulating autophagy of hepatic stellate cells and affecting the renin-angiotensin system.展开更多
BACKGROUND: 10-23 DNA enzyme is one kind of de-oxyribozymes for RNA cleavage. The inhibition effects of 10-23 DNA enzyme on the expression of the HBV C gene in HepG2. 2. 15 cells were demonstrated previously. The aim ...BACKGROUND: 10-23 DNA enzyme is one kind of de-oxyribozymes for RNA cleavage. The inhibition effects of 10-23 DNA enzyme on the expression of the HBV C gene in HepG2. 2. 15 cells were demonstrated previously. The aim of this study was to further explore the cleavage activities of 10-23 DNA enzyme targeting at HBV C gene mRNA in vitro. METHODS: 10-23 DNA enzyme named Drz-HBV-C-9 specific to HBV C gene ORF A1816UG was designed and synthesized. HBV C gene mRNA was obtained by the in vitro transcription method. Cleavage activities of Drz-HBV-C-9 were observed in vitro. Values of kinetic parameters including Km,Kcat and Kcat/Km were calculated accordingly. RESULTS: Under the certain cleavage conditions, Drz-HBV-C-9 could efficiently cleave target mRNA at specific sites in vitro. Cleavage products of 109nt plus 191nt were obtained. The kinetic parameters, Km,Kcat and Kcat/ Km for Drz-HBV-C-9, were 1.4 ×10-9 mol, 1.6 min-1 and 1.1 × 109 mol-1 · min-1, respectively. CONCLUSIONS: 10-23 DNA enzyme targeting at HBV C gene mRNA possesses specific cleavage activities in vitro. This would be a potent antiviral strategy with respect to HBV gene therapy.展开更多
The renin angiotensin system(RAS) is classically conceived as a circulating hormonal system involved in blood pressure control and hydroelectrolyte balance. The discovery that RAS components are locally expressed in a...The renin angiotensin system(RAS) is classically conceived as a circulating hormonal system involved in blood pressure control and hydroelectrolyte balance. The discovery that RAS components are locally expressed in a wide range of organs and tissues,including the liver,pointed to a role for this system in the pathogenesis of several conditions including hepatic fibrosis and cirrhosis. It has been widely reported that the classical RAS axis composed by the angiotensin converting enzyme(ACE)-angiotensin(Ang) Ⅱ-Ang type 1(AT1) receptor mediates pro-inflammatory,pro-thrombotic,and pro-fibrotic processes. On the other hand,the alternative axis comprising ACE2-Ang-(1-7)-Mas receptor seems to play a protective role by frequently opposing Ang Ⅱ action. Chronic hepatitis B(CHB) is one of the leading causes of liver fibrosis,accounting for the death of nearly one million people worldwide. Liver fibrosis is a key factor to determine therapeutic interventions for patients with CHB. However,the establishment of non-invasive and accurate methods to detect reversible stages of liver fibrosis is still a challenge. In an elegant study published in the 36 th issue of the World Journal of Gastroenterology,Noguchi et al showed the predictive value of serum ACE levels in detecting not only advanced stages of liver fibrosis but also initial and intermediate fibrotic stages. The serum levels of ACE might represent an accurate,non-invasive,widely available,and easy method to evaluate fibrosis related to CHB. Moreover,therapies involving the inhibition of the classical RAS axis components might be promising in the control of CHB-related liver fibrosis.展开更多
Objective:To isolate,identify,and evaluate a new angiotensin-converting enzyme inhibitor from Peperomia pellucida(L.)Kunth herbs.Methods:A dried sample of Peperomia pellucida herb was successively macerated with n-hex...Objective:To isolate,identify,and evaluate a new angiotensin-converting enzyme inhibitor from Peperomia pellucida(L.)Kunth herbs.Methods:A dried sample of Peperomia pellucida herb was successively macerated with n-hexane and ethyl acetate.The ethyl acetate extract solution was evaporated to obtain the crude extract.Vacuum liquid column chromatography and thin layer chromatography were performed to obtain two pure compounds.Then,both compounds were elucidated and identified using the spectroscopic method.Angiotensin-converting enzyme inhibitory activity studies of both compounds were determined using angiotensin-converting enzyme kit WST-1 with spectrophotometer microplate reader 96-well at 450 nm wavelength.Results:Two bioactive compounds were successfully isolated from Peperomia pellucida herb,including a new compound of 2,3,5-trimethoxy-9-(12,14,15-trimethoxybenzyl)-1 H-indene and pellucidin A.Both compounds demonstrated angiotensin-converting enzyme inhibitory activity,with IC50 values of 72 μM(27.95 μg/mL)and 1 1μM(4.4 μg/mL),respectively.Conclusions:In the present study,two active angiotensin-converting enzyme inhibitors were successfully isolated and purified from Peperomia pellucida which is used as an antihypertensive in traditional medicine,and support its use as an angiotensin-converting enzyme-inhibiting drug.展开更多
We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain injury.However,its impact on neuronal endoplasmic reticulum stress following repet...We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain injury.However,its impact on neuronal endoplasmic reticulum stress following repetitive mild traumatic brain injury remains unclear.In this study,we first used an HT22 scratch injury model to mimic traumatic brain injury,then co-cultured the HT22 cells with BV2 microglia expressing high levels of miR-124-3p.We found that exosomes containing high levels of miR-124-3p attenuated apoptosis and endoplasmic reticulum stress.Furthermore,luciferase reporter assay analysis confirmed that miR-124-3p bound specifically to the endoplasmic reticulum stress-related protein IRE1α,while an IRE1αfunctional salvage experiment confirmed that miR-124-3p targeted IRE1αand reduced its expression,thereby inhibiting endoplasmic reticulum stress in injured neurons.Finally,we delivered microglia-derived exosomes containing miR-124-3p intranasally to a mouse model of repetitive mild traumatic brain injury and found that endoplasmic reticulum stress and apoptosis levels in hippocampal neurons were significantly reduced.These findings suggest that,after repetitive mild traumatic brain injury,miR-124-3 can be transferred from microglia-derived exosomes to injured neurons,where it exerts a neuroprotective effect by inhibiting endoplasmic reticulum stress.Therefore,microglia-derived exosomes containing miR-124-3p may represent a novel therapeutic strategy for repetitive mild traumatic brain injury.展开更多
Tumor marker CA15-3 was determined by using capillary electrophoretic enzyme immunoassay with electrochemical detection (CE-EIA-ED). The method can be used to detect CA15-3 with a limit of 0.024 U/mL.
Aging is the leading risk factor for neurodegenerative diseases and oxidative stress involved in the pathophysiology of these diseases. These changes increase during menopausal condition in females when the level of e...Aging is the leading risk factor for neurodegenerative diseases and oxidative stress involved in the pathophysiology of these diseases. These changes increase during menopausal condition in females when the level of estradiol is decreased. The aim of the present study was to determine the effect of tachykinin neuropeptide, Neurokinin B (NKB) and Amyloid beta fragment Aβ (25 -?35) on 17β estradiol (E2) treated aging female rat synaptosomes of different age groups. Aging brain functions were assayed by measuring the activities of antioxidant enzymes—superoxide dismutase (SOD) and monoamine oxidase (MAO) with neuropeptides. An in-vitro incubation of Aβ (25 -?35) in E2 treated brain synaptosomes showed toxic effects on all the parameters. However, NKB and NKB combined with Aβ (25 35) showed stimulating effects in E2 treated rat brain synaptosomes. In the present study, an increase in activity of SOD and decrease in the level of MAO, in the presence of NKB and combined NKB and Aβ in E2 treated brain synaptosomes of aging rats. This study elucidates that treatment of NKB and Aβ with E2 incombination exerts more protective influence than their individual application, against excitotoxicity in age related changes.展开更多
Objective: To investigate the correlation of serum β-amyloid 1-42 (Aβ1-42) content with inflammatory factors and receptors as well as antioxidant enzymes in patients with Parkinson's Disease. Methods: A total of...Objective: To investigate the correlation of serum β-amyloid 1-42 (Aβ1-42) content with inflammatory factors and receptors as well as antioxidant enzymes in patients with Parkinson's Disease. Methods: A total of 48 patients with Parkinson's disease who were treated in this hospital between December 2014 and October 2017 were selected as Parkinson's disease group, and 50 healthy volunteers who received physical examination in this hospital during the same period were selected as normal control group. The differences in serum contents of Aβ1-42, inflammatory factors and receptors as well as antioxidant enzymes were compared between the two groups, and Pearson test was used to assess the correlation between serum Aβ1-42 content and illness in patients with Parkinson's disease. Results: Serum Aβ1-42 content of Parkinson's disease group was lower than that of normal control group;serum inflammatory factors and receptors IL-2, sIL-2R, IL-6 and sIL-6R contents were higher than those of normal control group;serum antioxidant enzymes SOD, GSH-Px, CAT and TPX contents were lower than those of control group. Pearson test showed that serum Aβ1-42 content of patients with Parkinson's disease was directly correlated with the contents of inflammatory factors and receptors as well as antioxidant enzymes. Conclusions: Serum Aβ1-42 content decreases in patient with Parkinson's disease, and the specific content is directly correlated with the condition of Parkinson's disease, and can be used as an important auxiliary indicator for diagnosis and judgment of Parkinson's disease.展开更多
Pot experiments were conducted to study the effect of Cl ̄- on transformation of fertilizer N, number ofmicroorganisms and enzyme activities in soils. It is indicated that Cl ̄- did not show significant influenceon to...Pot experiments were conducted to study the effect of Cl ̄- on transformation of fertilizer N, number ofmicroorganisms and enzyme activities in soils. It is indicated that Cl ̄- did not show significant influenceon total number of bacteria, actinomyces and fungi, but significantly reduced the number of nitrosobacteria,which led to decrease of NO content in the soil. Application of Cl ̄- to soil could significantly enhance theactivities of phosphatase and urease in the coastal saline soil and orthic aquisols. In hilly red soil, however,the application of Cl ̄- at the rate of 500-1000 mg Cl ̄- kg ̄(-1) soil significantly decreased the activity of thetwo enzymes mentioned above.展开更多
This paper sets out to summarize the literatures based on immobilized enzyme bio-chromatography and its application in inhibitors screening in the last decade.In order to screen enzyme inhibitors from a mass of compou...This paper sets out to summarize the literatures based on immobilized enzyme bio-chromatography and its application in inhibitors screening in the last decade.In order to screen enzyme inhibitors from a mass of compounds in preliminary screening,multi-pore materials with good biocompatibility are used for the supports of immobilizing enzymes,and then the immobilized enzyme reactor applied as the immobilized enzyme stationary phase in HPLC.Therefore,a technology platform of high throughput screening is gradually established to screen the enzyme inhibitors as new anti-tumor drugs.Here,we briefly summarize the selective methods of supports,immobilization techniques,co-immobilized enzymes system and the screening model.展开更多
A mathematical modelling of diagnostic biosensors system at three basic types of enzyme kinetics is discussed in the presence of diffusion. Enzyme kinetics is adopted to be first order, Michaelis-Menten and ping-pong ...A mathematical modelling of diagnostic biosensors system at three basic types of enzyme kinetics is discussed in the presence of diffusion. Enzyme kinetics is adopted to be first order, Michaelis-Menten and ping-pong mechanism. In this paper, approximate analytical solutions are obtained for the non-linear equations under steady-state conditions by using the new Homotopy perturbation method. Simple and closed forms of analytical expressions for concentrations of substrate, product and co-substrate and corresponding current response have been derived for all possible values of parameters. Furthermore, the numerical simulation of the problem is also reported here by using Matlab program. Good agreement between analytical and numerical results is noted.展开更多
Objective: Evaluating the bio-reducing activity and various potential, annotates the biological entitties of Fagonia cretica. Method: By fractionating the crude extract with different ethanol-water fraction mixture. T...Objective: Evaluating the bio-reducing activity and various potential, annotates the biological entitties of Fagonia cretica. Method: By fractionating the crude extract with different ethanol-water fraction mixture. This substantiates the reduction potential for the biological synthesis of AgNPs, its antioxidant, anti-urease and anti-Tyrosinase activity. Results: UV-visible spectra confirm the bio-reducing potential for Ag NPs with the optimized 50% ethanol-water fraction mixture. Transmission electron microscopy (TEM) confirmed the round shaped AgNPs with an average size of 16 nm in optimized 50% fraction mixture. Further evaluating Ethanol-water fraction with 90% and 70% of plant extract showed more potentials for Anti-Tyrosinase and Anti-urease activity. Moreover, diluted 30% fraction exhibits two folds higher Anti-oxidant and Anti urease activity. Conclusion: Overall, this work showed that 50% Ethanol-water fraction has potentially active molecules (among all fractions) primarily involved in bio-reducing potential of Ag NPs and enzymatic assay while 90% mixture proved to be least active. This study suggested electing the optimum mixture fraction of 50% ethanol-water in order to screen the bioactive compounds and to inculcate their activity status for clinical trials.展开更多
A new kind of bio-fluid bed used to treat dyes wastewater is described in detail due to its several special features,such as high removal efficiency,simple struc-ture,shock load resistance,etc.By means of analyzing th...A new kind of bio-fluid bed used to treat dyes wastewater is described in detail due to its several special features,such as high removal efficiency,simple struc-ture,shock load resistance,etc.By means of analyzing the experiment data,the results show that the dye wastewater’s organic matter is removed greatly after be-ing treated by this new kind of bio-fluid bed.On the other hand,the removal efficiency of chromaticity of展开更多
The aim of this project is to find out the changes that occur in physical properties of denim when it is subjected to enzyme stone and acid wash or to find out the impact of enzyme stone and acid wash. 97% cotton 3% e...The aim of this project is to find out the changes that occur in physical properties of denim when it is subjected to enzyme stone and acid wash or to find out the impact of enzyme stone and acid wash. 97% cotton 3% elastomer twill, weave 3/1, construction 72 × 40/9 × 7 indigo dyed denim fabric leg panels as per lab standard recipe are used here to examine. Firstly, desizing was done as pre-treatments and after treatment was silicon softener. After washing process, different samples from both washing are going to express different behavior on physical properties. This experiment is done to find out the discrimination in tearing strength, shrinkage %, color fastness to wash, color fastness to rubbing, pH rate between stone enzyme wash and acid wash of denim garments.展开更多
文摘The present letter to the editor is related to the study titled‘Angiotensin-converting enzyme 2 improves liver fibrosis in mice by regulating autophagy of hepatic stellate cells’.Angiotensin-converting enzyme 2 can alleviate liver fibrosis by regulating autophagy of hepatic stellate cells and affecting the renin-angiotensin system.
基金This study was supported by a grant from the National Natural Science Foundation of China (No. 30271183).
文摘BACKGROUND: 10-23 DNA enzyme is one kind of de-oxyribozymes for RNA cleavage. The inhibition effects of 10-23 DNA enzyme on the expression of the HBV C gene in HepG2. 2. 15 cells were demonstrated previously. The aim of this study was to further explore the cleavage activities of 10-23 DNA enzyme targeting at HBV C gene mRNA in vitro. METHODS: 10-23 DNA enzyme named Drz-HBV-C-9 specific to HBV C gene ORF A1816UG was designed and synthesized. HBV C gene mRNA was obtained by the in vitro transcription method. Cleavage activities of Drz-HBV-C-9 were observed in vitro. Values of kinetic parameters including Km,Kcat and Kcat/Km were calculated accordingly. RESULTS: Under the certain cleavage conditions, Drz-HBV-C-9 could efficiently cleave target mRNA at specific sites in vitro. Cleavage products of 109nt plus 191nt were obtained. The kinetic parameters, Km,Kcat and Kcat/ Km for Drz-HBV-C-9, were 1.4 ×10-9 mol, 1.6 min-1 and 1.1 × 109 mol-1 · min-1, respectively. CONCLUSIONS: 10-23 DNA enzyme targeting at HBV C gene mRNA possesses specific cleavage activities in vitro. This would be a potent antiviral strategy with respect to HBV gene therapy.
基金Supported by CNPq,No.460334/2014-0FAPEMIG,No.CDS-PPM-00555-15(to Simoes e Silva AC)2016 NARSAD Young Investigator Grant Awardee from the Brain and Behavior Research Foundation,No.25414(to Miranda AS)
文摘The renin angiotensin system(RAS) is classically conceived as a circulating hormonal system involved in blood pressure control and hydroelectrolyte balance. The discovery that RAS components are locally expressed in a wide range of organs and tissues,including the liver,pointed to a role for this system in the pathogenesis of several conditions including hepatic fibrosis and cirrhosis. It has been widely reported that the classical RAS axis composed by the angiotensin converting enzyme(ACE)-angiotensin(Ang) Ⅱ-Ang type 1(AT1) receptor mediates pro-inflammatory,pro-thrombotic,and pro-fibrotic processes. On the other hand,the alternative axis comprising ACE2-Ang-(1-7)-Mas receptor seems to play a protective role by frequently opposing Ang Ⅱ action. Chronic hepatitis B(CHB) is one of the leading causes of liver fibrosis,accounting for the death of nearly one million people worldwide. Liver fibrosis is a key factor to determine therapeutic interventions for patients with CHB. However,the establishment of non-invasive and accurate methods to detect reversible stages of liver fibrosis is still a challenge. In an elegant study published in the 36 th issue of the World Journal of Gastroenterology,Noguchi et al showed the predictive value of serum ACE levels in detecting not only advanced stages of liver fibrosis but also initial and intermediate fibrotic stages. The serum levels of ACE might represent an accurate,non-invasive,widely available,and easy method to evaluate fibrosis related to CHB. Moreover,therapies involving the inhibition of the classical RAS axis components might be promising in the control of CHB-related liver fibrosis.
基金supported by grant “Hibah Tugas Akhir Mahasiswa Doktor(TADOK)Tahun 2018” Directorate of Research and Humanity Engagement Universitas Indonesia(grant number:1234/UN2.R3.1/HKP.05.00/2018)
文摘Objective:To isolate,identify,and evaluate a new angiotensin-converting enzyme inhibitor from Peperomia pellucida(L.)Kunth herbs.Methods:A dried sample of Peperomia pellucida herb was successively macerated with n-hexane and ethyl acetate.The ethyl acetate extract solution was evaporated to obtain the crude extract.Vacuum liquid column chromatography and thin layer chromatography were performed to obtain two pure compounds.Then,both compounds were elucidated and identified using the spectroscopic method.Angiotensin-converting enzyme inhibitory activity studies of both compounds were determined using angiotensin-converting enzyme kit WST-1 with spectrophotometer microplate reader 96-well at 450 nm wavelength.Results:Two bioactive compounds were successfully isolated from Peperomia pellucida herb,including a new compound of 2,3,5-trimethoxy-9-(12,14,15-trimethoxybenzyl)-1 H-indene and pellucidin A.Both compounds demonstrated angiotensin-converting enzyme inhibitory activity,with IC50 values of 72 μM(27.95 μg/mL)and 1 1μM(4.4 μg/mL),respectively.Conclusions:In the present study,two active angiotensin-converting enzyme inhibitors were successfully isolated and purified from Peperomia pellucida which is used as an antihypertensive in traditional medicine,and support its use as an angiotensin-converting enzyme-inhibiting drug.
基金supported by the Haihe Laboratory of Cell Ecosystem Innovation Fund,No.22HHXBSS00047(to PL)the National Natural Science Foundation of China,Nos.82072166(to PL),82071394(to XG)+4 种基金Science and Technology Planning Project of Tianjin,No.20YFZCSY00030(to PL)Science and Technology Project of Tianjin Municipal Health Commission,No.TJWJ2021QN005(to XG)Tianjin Key Medical Discipline(Specialty)Construction Project,No.TJYXZDXK-006ATianjin Municipal Education Commission Scientific Research Program Project,No.2020KJ164(to JZ)China Postdoctoral Science Foundation,No.2022M712392(to ZY).
文摘We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain injury.However,its impact on neuronal endoplasmic reticulum stress following repetitive mild traumatic brain injury remains unclear.In this study,we first used an HT22 scratch injury model to mimic traumatic brain injury,then co-cultured the HT22 cells with BV2 microglia expressing high levels of miR-124-3p.We found that exosomes containing high levels of miR-124-3p attenuated apoptosis and endoplasmic reticulum stress.Furthermore,luciferase reporter assay analysis confirmed that miR-124-3p bound specifically to the endoplasmic reticulum stress-related protein IRE1α,while an IRE1αfunctional salvage experiment confirmed that miR-124-3p targeted IRE1αand reduced its expression,thereby inhibiting endoplasmic reticulum stress in injured neurons.Finally,we delivered microglia-derived exosomes containing miR-124-3p intranasally to a mouse model of repetitive mild traumatic brain injury and found that endoplasmic reticulum stress and apoptosis levels in hippocampal neurons were significantly reduced.These findings suggest that,after repetitive mild traumatic brain injury,miR-124-3 can be transferred from microglia-derived exosomes to injured neurons,where it exerts a neuroprotective effect by inhibiting endoplasmic reticulum stress.Therefore,microglia-derived exosomes containing miR-124-3p may represent a novel therapeutic strategy for repetitive mild traumatic brain injury.
文摘Tumor marker CA15-3 was determined by using capillary electrophoretic enzyme immunoassay with electrochemical detection (CE-EIA-ED). The method can be used to detect CA15-3 with a limit of 0.024 U/mL.
文摘Aging is the leading risk factor for neurodegenerative diseases and oxidative stress involved in the pathophysiology of these diseases. These changes increase during menopausal condition in females when the level of estradiol is decreased. The aim of the present study was to determine the effect of tachykinin neuropeptide, Neurokinin B (NKB) and Amyloid beta fragment Aβ (25 -?35) on 17β estradiol (E2) treated aging female rat synaptosomes of different age groups. Aging brain functions were assayed by measuring the activities of antioxidant enzymes—superoxide dismutase (SOD) and monoamine oxidase (MAO) with neuropeptides. An in-vitro incubation of Aβ (25 -?35) in E2 treated brain synaptosomes showed toxic effects on all the parameters. However, NKB and NKB combined with Aβ (25 35) showed stimulating effects in E2 treated rat brain synaptosomes. In the present study, an increase in activity of SOD and decrease in the level of MAO, in the presence of NKB and combined NKB and Aβ in E2 treated brain synaptosomes of aging rats. This study elucidates that treatment of NKB and Aβ with E2 incombination exerts more protective influence than their individual application, against excitotoxicity in age related changes.
文摘Objective: To investigate the correlation of serum β-amyloid 1-42 (Aβ1-42) content with inflammatory factors and receptors as well as antioxidant enzymes in patients with Parkinson's Disease. Methods: A total of 48 patients with Parkinson's disease who were treated in this hospital between December 2014 and October 2017 were selected as Parkinson's disease group, and 50 healthy volunteers who received physical examination in this hospital during the same period were selected as normal control group. The differences in serum contents of Aβ1-42, inflammatory factors and receptors as well as antioxidant enzymes were compared between the two groups, and Pearson test was used to assess the correlation between serum Aβ1-42 content and illness in patients with Parkinson's disease. Results: Serum Aβ1-42 content of Parkinson's disease group was lower than that of normal control group;serum inflammatory factors and receptors IL-2, sIL-2R, IL-6 and sIL-6R contents were higher than those of normal control group;serum antioxidant enzymes SOD, GSH-Px, CAT and TPX contents were lower than those of control group. Pearson test showed that serum Aβ1-42 content of patients with Parkinson's disease was directly correlated with the contents of inflammatory factors and receptors as well as antioxidant enzymes. Conclusions: Serum Aβ1-42 content decreases in patient with Parkinson's disease, and the specific content is directly correlated with the condition of Parkinson's disease, and can be used as an important auxiliary indicator for diagnosis and judgment of Parkinson's disease.
文摘Pot experiments were conducted to study the effect of Cl ̄- on transformation of fertilizer N, number ofmicroorganisms and enzyme activities in soils. It is indicated that Cl ̄- did not show significant influenceon total number of bacteria, actinomyces and fungi, but significantly reduced the number of nitrosobacteria,which led to decrease of NO content in the soil. Application of Cl ̄- to soil could significantly enhance theactivities of phosphatase and urease in the coastal saline soil and orthic aquisols. In hilly red soil, however,the application of Cl ̄- at the rate of 500-1000 mg Cl ̄- kg ̄(-1) soil significantly decreased the activity of thetwo enzymes mentioned above.
基金supported by the Province Natural Science Foundation of Shandong (Grant number 2009ZRB02230)
文摘This paper sets out to summarize the literatures based on immobilized enzyme bio-chromatography and its application in inhibitors screening in the last decade.In order to screen enzyme inhibitors from a mass of compounds in preliminary screening,multi-pore materials with good biocompatibility are used for the supports of immobilizing enzymes,and then the immobilized enzyme reactor applied as the immobilized enzyme stationary phase in HPLC.Therefore,a technology platform of high throughput screening is gradually established to screen the enzyme inhibitors as new anti-tumor drugs.Here,we briefly summarize the selective methods of supports,immobilization techniques,co-immobilized enzymes system and the screening model.
文摘A mathematical modelling of diagnostic biosensors system at three basic types of enzyme kinetics is discussed in the presence of diffusion. Enzyme kinetics is adopted to be first order, Michaelis-Menten and ping-pong mechanism. In this paper, approximate analytical solutions are obtained for the non-linear equations under steady-state conditions by using the new Homotopy perturbation method. Simple and closed forms of analytical expressions for concentrations of substrate, product and co-substrate and corresponding current response have been derived for all possible values of parameters. Furthermore, the numerical simulation of the problem is also reported here by using Matlab program. Good agreement between analytical and numerical results is noted.
文摘Objective: Evaluating the bio-reducing activity and various potential, annotates the biological entitties of Fagonia cretica. Method: By fractionating the crude extract with different ethanol-water fraction mixture. This substantiates the reduction potential for the biological synthesis of AgNPs, its antioxidant, anti-urease and anti-Tyrosinase activity. Results: UV-visible spectra confirm the bio-reducing potential for Ag NPs with the optimized 50% ethanol-water fraction mixture. Transmission electron microscopy (TEM) confirmed the round shaped AgNPs with an average size of 16 nm in optimized 50% fraction mixture. Further evaluating Ethanol-water fraction with 90% and 70% of plant extract showed more potentials for Anti-Tyrosinase and Anti-urease activity. Moreover, diluted 30% fraction exhibits two folds higher Anti-oxidant and Anti urease activity. Conclusion: Overall, this work showed that 50% Ethanol-water fraction has potentially active molecules (among all fractions) primarily involved in bio-reducing potential of Ag NPs and enzymatic assay while 90% mixture proved to be least active. This study suggested electing the optimum mixture fraction of 50% ethanol-water in order to screen the bioactive compounds and to inculcate their activity status for clinical trials.
文摘A new kind of bio-fluid bed used to treat dyes wastewater is described in detail due to its several special features,such as high removal efficiency,simple struc-ture,shock load resistance,etc.By means of analyzing the experiment data,the results show that the dye wastewater’s organic matter is removed greatly after be-ing treated by this new kind of bio-fluid bed.On the other hand,the removal efficiency of chromaticity of
文摘The aim of this project is to find out the changes that occur in physical properties of denim when it is subjected to enzyme stone and acid wash or to find out the impact of enzyme stone and acid wash. 97% cotton 3% elastomer twill, weave 3/1, construction 72 × 40/9 × 7 indigo dyed denim fabric leg panels as per lab standard recipe are used here to examine. Firstly, desizing was done as pre-treatments and after treatment was silicon softener. After washing process, different samples from both washing are going to express different behavior on physical properties. This experiment is done to find out the discrimination in tearing strength, shrinkage %, color fastness to wash, color fastness to rubbing, pH rate between stone enzyme wash and acid wash of denim garments.