The iron oxide nanoparticles have been synthesized in co-precipitation method using aqueous solution of ferric and ferrous ions with sodium salt. The synthesis of iron-oxide nanoparticles were validated by UV-Visible ...The iron oxide nanoparticles have been synthesized in co-precipitation method using aqueous solution of ferric and ferrous ions with sodium salt. The synthesis of iron-oxide nanoparticles were validated by UV-Visible spectroscopy which showed higher peak at 370 nm as valid standard reference. An average size of iron oxide nanoparticle found by Diffraction Light scattering (DLS) particle size analyser, ranges approximately between 10 nm to 120 nm with mean particle size of 66 nm. The X-ray power diffraction (XRD) analysis revealed the crystallographic structure of magnetic particles. Characterization of the mean particle size and morphology of iron oxide nanoparticles confirmed that the iron oxide nanoparticles are nearly spherical and crystalline in shape. Further the antibacterial effect of iron oxide nanoparticles was evaluated against ten pathogenic bacteria which showed that the nanoparticles have moderate antibacterial activity against both Gram positive and Gram negative pathogenic bacterial strains and retains potential application in pharmaceutical and biomedical industries.展开更多
The aim of this work was to study the efficiency of native lignocellulolytic enzymes obtained from isolated bacteria towards enhanced bioethanol production from lignocellulosic biomass.Maximum cellulose(199.33±0....The aim of this work was to study the efficiency of native lignocellulolytic enzymes obtained from isolated bacteria towards enhanced bioethanol production from lignocellulosic biomass.Maximum cellulose(199.33±0.2 mg/g)and hemicellulose(62.21±0.22 mg/g)content was measured from rice straw in alkali condition compared to acid and biological pretreatment,while significant lignin removal has been observed in biological pretreatment.Saccharification of rice straw using isolated cellulase–xylanase enzymes exhibited 60.33%production of total reducing sugar obtained by commercial cellulase–xylanase cocktail.Maximum glucose,xylose,and total reducing sugar yield of 309±0.32,190.7±0.42,and 499.7±0.37 mg/g,respec-tively,at 37.5℃,pH-7,rice straw concentration of 2.5 g/100 mL,enzyme loading 175μl,and incubation period 42 h by com-mercial cellulase–xylanase enzyme mediated hydrolysis.While in case of using the native cellulase–xylanase cocktail from the isolated bacterial strains,highest yields of glucose,xylose and total reducing sugar production was 253.52±0.56 mg/g,47.94±0.78 mg/g,and 301.46±0.67 mg/g,respectively.While applying the isolated enzymes on alkali-pretreated rice straw,bioethanol concentration of around 32.57±0.25 g/L was recorded after the simultaneous saccharification and fermentation by Saccharomyces cerevisiae.The above mentioned bioethanol concentration was obtained at a process parameter of temperature 35℃,incubation time 58 h,and pH 5.5 for isolated cellulase–xylanase enzymes.A maximum bioethanol concentration using isolated cellulase–xylanase enzymes was nearly 93.89%of bioethanol concentration(34.69±0.28 g/L)obtained using commercial cellulase–xylanase.The present study interpreted that the cutting-edge approach for the native enzymes along with metabolic engineering of the isolated bacteria could be promising towards enhanced bioethanol production.展开更多
Xylanolytic enzyme can successfully and efficiently breakdown xylans to fermentable carbohydrates to create useful chemicals or fuels for use in a range of industrial sectors such as food,animal feed,biofuel,pulp,and ...Xylanolytic enzyme can successfully and efficiently breakdown xylans to fermentable carbohydrates to create useful chemicals or fuels for use in a range of industrial sectors such as food,animal feed,biofuel,pulp,and paper.In the current investigation,molecular modeling and docking analysis were performed using xylanase enzymes from 17 different fungal species with 5 substrates such as d-xylose,xylobiose,xylotriose,xylotetrose,and xylopentose to identify the active site residues and binding affinity of those complexes.Among all,4 fungal species such as Aspergillus niger,Orpinomyces sp.,Neocallimastix patriciarum,and Botrytis fuckeliana showed the maximum molecular interaction and binding affinity toward different sub-strate,i.e.,−5.4(d-xylose),−6.7(xylobiose),−8.2(xylotriose),−8.1(Xylotetrose),and−5(xylopentose)kcal/mol.These four complexes were used for the simulation studies to determine its constancy of the enzyme-substrate complexes.Thus,Botrytis fuckeliana with xylobiose ligand and N.patriciarum with xylotetrose can substantially involve in xylan degradation toward bioethanol production from lignocellulosic biomass.展开更多
Chromite mine soil is highly contaminated with different heavy metals like chromium,cadmium,lead,and arsenic.In the present study,42 numbers of metal-tolerant bacteria(Cr-14,Cd-9,Pb-11,and As-8)were isolated from thre...Chromite mine soil is highly contaminated with different heavy metals like chromium,cadmium,lead,and arsenic.In the present study,42 numbers of metal-tolerant bacteria(Cr-14,Cd-9,Pb-11,and As-8)were isolated from three soil samples collected from chromite mine soils of Sukinda,Odisha using nutrient broth medium supplemented with 50 mg/L of each of the above four metals.The isolated metal-tolerant bacteria were screened using increased above mentioned metal ion concentrations(50,100 ppm,200,500,700,and 1000 mg/L)to know the maximum resistance of the bacteria towards a particular metal.Out of the 42 predominant bacterial isolates,4 bacteria(CrS_(2)C_(7),PbS_(1)M_(1),CdS_(2)M_(1) and AsS_(1)M_(2))showing high resistance to respective metal ions were subjected to biochemical characterization followed by 16S rRNA sequencing and identified as Pseudomonas argentinensis(CrS_(2)C_(7)),Bacillus subtilis(PbS_(1)M_(1)),Bacillus thuringiensis(CdS_(2)M_(1)),and Bacillus fungorum(AsS_(1)M_(2)).Further,the Cr^(+6) biosorption potential of these 4 bacteria(CrS_(2)C_(7),PbS_(1)M_(1),AsS_(1)M_(2),and CdS_(2)M_(1))were evaluated using 100 mg/L K2Cr_(2)O_(7) metal solution.Out of the above four isolates,P.argentinensis showed highest biosorption of 73.4%for Cr^(+6) metal ion solution The present finding of Cr^(+6) biosorption by P.argentinensis indicates that it can be used as an effective biosorbent for biosorption of Cr^(+6) from chromate contaminated aqueous environment.展开更多
Objective： To test the antioxidant, antidiabetic, anticancer and antibacterial activities along with phytochemicals of Sonneratia apetala Buch.-Ham. Methods： The antibacterial activity was determined by agar well di...Objective： To test the antioxidant, antidiabetic, anticancer and antibacterial activities along with phytochemicals of Sonneratia apetala Buch.-Ham. Methods： The antibacterial activity was determined by agar well diffusion method. The antioxidant activity was determined by standard assay. The antidiabetic activity was evaluated by α-glucosidase inhibition assay and in vivo anticancer property was determined against Ehrlich ascites carcinoma （EAC） cells in Swiss Albino mice. Further partial characterization of the methanol extracts was carried out by thin layer chromatography, high performance liquid chromatography, 1H nuclear magnetic resonance spectroscopy and Fourier transform-infra red spectrum spectral analysis. Results： Four solvent extracts （acetone, ethanol, methanol and aqueous） of leaf and bark possess strong antioxidant properties. In vivo anticancer activity of methanol extract leaf indicated positive activity showing 34% inhibition against EAC cells in Swiss Albino mice. All extracts exhibited a-glucosidase inhibitory activity in a dose-dependent manner indicating presence of promising antidiabetic properties. The extracts possess strong antibacterial activity against the selected pathogenic bacteria （minimal inhibitory concentration ranging from 1.25-5.00 mg/mL）. The partial characterization of the methanol extracts of leaf and bark revealed the presence of phenolics as the lead compound responsible for studied bioactivities of the plant extracts. Conclusion： Sonneratia apetala extracts have potent antibacterial, antioxidant, antidiabetic and anticancer properties which can be further exploited for its pharmaceutical applications.展开更多
Lignocellulosic grass biomass is potential substrate for economical and sustainable bioethanol production.However,the processing cost of bioethanol that majorly includes the hydrolysis of cellulose by cellulases is st...Lignocellulosic grass biomass is potential substrate for economical and sustainable bioethanol production.However,the processing cost of bioethanol that majorly includes the hydrolysis of cellulose by cellulases is still a major concern for its industrial production.Thus,knowledge on the sequence to the structural study of cellulase enzyme with consideration of its catalytic region can give important information for effective enzyme engineering and consequently towards enhanced bioethanol production from Pennisetum sp.Therefore,in this study,sequence conservativeness of different cellulosic site among a group of endoglucanase family of cellulase from previously isolated Aspergillus species has been determined.Furthermore,comparative molecular modeling of the endoglucanase from eight different Aspergillus species including Aspergillus fumigatus was conducted and the obtained structures revealed a high degree of difference in their conformational folds.Analysis from InterProScan revealed that the modeled endoglucanase has similar types of domains and share homology with protein family,such as glycoside hydrolase family-61 and fungal cellulose binding domain.Furthermore,molecular docking and interaction studies demonstrated the presence of residues in the endoglucanase of A.fumigatus viz.His20,His88,Asp96,Ala99,Ser100,Ser101,His102,His169,Glu170,Arg173,Glu178,and Tyr218 that are responsible in forming the substrate interaction.An interesting molecular phenomenon,i.e.,catalytic promiscuity has been noted for all the substrate bound complexes of A.fumigatus endoglucanase which also depicts the degree of ligand binding efficacy of the studied enzyme.The molecular interaction study,binding energy analysis and molecular dynamics simulation,demonstrated that heteromeric substrate XylGlc3 is more strongly interacting with the receptor enzyme.Overall,the present findings revealed that important amino acid residues can help in increasing the specificity of endoglucanase from A.fumigatus towards hydrolysis of Pennisetum sp.and other biomass that has an adequate amount of XylGlc3,for possible industrial applications.展开更多
Laccases are versatile enzymes that belong to the multi-copper oxidase family.This enzyme has several biotechnological applications because of its ablilty to oxidize a wide range of phenolic and non-phenolic substrate...Laccases are versatile enzymes that belong to the multi-copper oxidase family.This enzyme has several biotechnological applications because of its ablilty to oxidize a wide range of phenolic and non-phenolic substrates.However,their large-scale applicability in bioremediation and water treatment is hindered by high salt content and extreme pH values of the polluted media which also affects the stability,recovery and recycling of laccase.Apart from some bacteria,laccase is abundantly present in several lignin-degrading white-rot fungi viz.Ascomycetes,Deuteromycetes,and Basidiomycetes.Recently,lac-case has been employed in the development of biosensors as a medical diagnostic tool,biofuel cells,and in bioremediation purpose to remove herbicides,pesticides,and some toxic chemicals from the soil.However,most of the enzymes including laccase are normally unstable and susceptible to lose their activity over time.This might be avoided by maintaining the activity and lengthening the enzyme's lifespan through the use of appropriate immobilization procedures.The potential of laccase immobilized biocathodes for dye decolorization in microbial fuel cells has recently been studied.Immobilized laccase nanoparticles have potential uses as biocatalyst in the bioremediation of pollutants.In addition,advanced research considering microbial laccase has been conducted for its heterologous expression along with in silico protein engineering to attain maximum enzyme activity which can be potentially applied in different biotechnological sectors.Patent related to laccase also implied that this enzyme can be used as suitable catalyst for the production of promising anti-cancer drugs and even as a significant ingredient in cosmetics.展开更多
文摘The iron oxide nanoparticles have been synthesized in co-precipitation method using aqueous solution of ferric and ferrous ions with sodium salt. The synthesis of iron-oxide nanoparticles were validated by UV-Visible spectroscopy which showed higher peak at 370 nm as valid standard reference. An average size of iron oxide nanoparticle found by Diffraction Light scattering (DLS) particle size analyser, ranges approximately between 10 nm to 120 nm with mean particle size of 66 nm. The X-ray power diffraction (XRD) analysis revealed the crystallographic structure of magnetic particles. Characterization of the mean particle size and morphology of iron oxide nanoparticles confirmed that the iron oxide nanoparticles are nearly spherical and crystalline in shape. Further the antibacterial effect of iron oxide nanoparticles was evaluated against ten pathogenic bacteria which showed that the nanoparticles have moderate antibacterial activity against both Gram positive and Gram negative pathogenic bacterial strains and retains potential application in pharmaceutical and biomedical industries.
文摘The aim of this work was to study the efficiency of native lignocellulolytic enzymes obtained from isolated bacteria towards enhanced bioethanol production from lignocellulosic biomass.Maximum cellulose(199.33±0.2 mg/g)and hemicellulose(62.21±0.22 mg/g)content was measured from rice straw in alkali condition compared to acid and biological pretreatment,while significant lignin removal has been observed in biological pretreatment.Saccharification of rice straw using isolated cellulase–xylanase enzymes exhibited 60.33%production of total reducing sugar obtained by commercial cellulase–xylanase cocktail.Maximum glucose,xylose,and total reducing sugar yield of 309±0.32,190.7±0.42,and 499.7±0.37 mg/g,respec-tively,at 37.5℃,pH-7,rice straw concentration of 2.5 g/100 mL,enzyme loading 175μl,and incubation period 42 h by com-mercial cellulase–xylanase enzyme mediated hydrolysis.While in case of using the native cellulase–xylanase cocktail from the isolated bacterial strains,highest yields of glucose,xylose and total reducing sugar production was 253.52±0.56 mg/g,47.94±0.78 mg/g,and 301.46±0.67 mg/g,respectively.While applying the isolated enzymes on alkali-pretreated rice straw,bioethanol concentration of around 32.57±0.25 g/L was recorded after the simultaneous saccharification and fermentation by Saccharomyces cerevisiae.The above mentioned bioethanol concentration was obtained at a process parameter of temperature 35℃,incubation time 58 h,and pH 5.5 for isolated cellulase–xylanase enzymes.A maximum bioethanol concentration using isolated cellulase–xylanase enzymes was nearly 93.89%of bioethanol concentration(34.69±0.28 g/L)obtained using commercial cellulase–xylanase.The present study interpreted that the cutting-edge approach for the native enzymes along with metabolic engineering of the isolated bacteria could be promising towards enhanced bioethanol production.
文摘Xylanolytic enzyme can successfully and efficiently breakdown xylans to fermentable carbohydrates to create useful chemicals or fuels for use in a range of industrial sectors such as food,animal feed,biofuel,pulp,and paper.In the current investigation,molecular modeling and docking analysis were performed using xylanase enzymes from 17 different fungal species with 5 substrates such as d-xylose,xylobiose,xylotriose,xylotetrose,and xylopentose to identify the active site residues and binding affinity of those complexes.Among all,4 fungal species such as Aspergillus niger,Orpinomyces sp.,Neocallimastix patriciarum,and Botrytis fuckeliana showed the maximum molecular interaction and binding affinity toward different sub-strate,i.e.,−5.4(d-xylose),−6.7(xylobiose),−8.2(xylotriose),−8.1(Xylotetrose),and−5(xylopentose)kcal/mol.These four complexes were used for the simulation studies to determine its constancy of the enzyme-substrate complexes.Thus,Botrytis fuckeliana with xylobiose ligand and N.patriciarum with xylotetrose can substantially involve in xylan degradation toward bioethanol production from lignocellulosic biomass.
文摘Chromite mine soil is highly contaminated with different heavy metals like chromium,cadmium,lead,and arsenic.In the present study,42 numbers of metal-tolerant bacteria(Cr-14,Cd-9,Pb-11,and As-8)were isolated from three soil samples collected from chromite mine soils of Sukinda,Odisha using nutrient broth medium supplemented with 50 mg/L of each of the above four metals.The isolated metal-tolerant bacteria were screened using increased above mentioned metal ion concentrations(50,100 ppm,200,500,700,and 1000 mg/L)to know the maximum resistance of the bacteria towards a particular metal.Out of the 42 predominant bacterial isolates,4 bacteria(CrS_(2)C_(7),PbS_(1)M_(1),CdS_(2)M_(1) and AsS_(1)M_(2))showing high resistance to respective metal ions were subjected to biochemical characterization followed by 16S rRNA sequencing and identified as Pseudomonas argentinensis(CrS_(2)C_(7)),Bacillus subtilis(PbS_(1)M_(1)),Bacillus thuringiensis(CdS_(2)M_(1)),and Bacillus fungorum(AsS_(1)M_(2)).Further,the Cr^(+6) biosorption potential of these 4 bacteria(CrS_(2)C_(7),PbS_(1)M_(1),AsS_(1)M_(2),and CdS_(2)M_(1))were evaluated using 100 mg/L K2Cr_(2)O_(7) metal solution.Out of the above four isolates,P.argentinensis showed highest biosorption of 73.4%for Cr^(+6) metal ion solution The present finding of Cr^(+6) biosorption by P.argentinensis indicates that it can be used as an effective biosorbent for biosorption of Cr^(+6) from chromate contaminated aqueous environment.
文摘Objective： To test the antioxidant, antidiabetic, anticancer and antibacterial activities along with phytochemicals of Sonneratia apetala Buch.-Ham. Methods： The antibacterial activity was determined by agar well diffusion method. The antioxidant activity was determined by standard assay. The antidiabetic activity was evaluated by α-glucosidase inhibition assay and in vivo anticancer property was determined against Ehrlich ascites carcinoma （EAC） cells in Swiss Albino mice. Further partial characterization of the methanol extracts was carried out by thin layer chromatography, high performance liquid chromatography, 1H nuclear magnetic resonance spectroscopy and Fourier transform-infra red spectrum spectral analysis. Results： Four solvent extracts （acetone, ethanol, methanol and aqueous） of leaf and bark possess strong antioxidant properties. In vivo anticancer activity of methanol extract leaf indicated positive activity showing 34% inhibition against EAC cells in Swiss Albino mice. All extracts exhibited a-glucosidase inhibitory activity in a dose-dependent manner indicating presence of promising antidiabetic properties. The extracts possess strong antibacterial activity against the selected pathogenic bacteria （minimal inhibitory concentration ranging from 1.25-5.00 mg/mL）. The partial characterization of the methanol extracts of leaf and bark revealed the presence of phenolics as the lead compound responsible for studied bioactivities of the plant extracts. Conclusion： Sonneratia apetala extracts have potent antibacterial, antioxidant, antidiabetic and anticancer properties which can be further exploited for its pharmaceutical applications.
文摘Lignocellulosic grass biomass is potential substrate for economical and sustainable bioethanol production.However,the processing cost of bioethanol that majorly includes the hydrolysis of cellulose by cellulases is still a major concern for its industrial production.Thus,knowledge on the sequence to the structural study of cellulase enzyme with consideration of its catalytic region can give important information for effective enzyme engineering and consequently towards enhanced bioethanol production from Pennisetum sp.Therefore,in this study,sequence conservativeness of different cellulosic site among a group of endoglucanase family of cellulase from previously isolated Aspergillus species has been determined.Furthermore,comparative molecular modeling of the endoglucanase from eight different Aspergillus species including Aspergillus fumigatus was conducted and the obtained structures revealed a high degree of difference in their conformational folds.Analysis from InterProScan revealed that the modeled endoglucanase has similar types of domains and share homology with protein family,such as glycoside hydrolase family-61 and fungal cellulose binding domain.Furthermore,molecular docking and interaction studies demonstrated the presence of residues in the endoglucanase of A.fumigatus viz.His20,His88,Asp96,Ala99,Ser100,Ser101,His102,His169,Glu170,Arg173,Glu178,and Tyr218 that are responsible in forming the substrate interaction.An interesting molecular phenomenon,i.e.,catalytic promiscuity has been noted for all the substrate bound complexes of A.fumigatus endoglucanase which also depicts the degree of ligand binding efficacy of the studied enzyme.The molecular interaction study,binding energy analysis and molecular dynamics simulation,demonstrated that heteromeric substrate XylGlc3 is more strongly interacting with the receptor enzyme.Overall,the present findings revealed that important amino acid residues can help in increasing the specificity of endoglucanase from A.fumigatus towards hydrolysis of Pennisetum sp.and other biomass that has an adequate amount of XylGlc3,for possible industrial applications.
文摘Laccases are versatile enzymes that belong to the multi-copper oxidase family.This enzyme has several biotechnological applications because of its ablilty to oxidize a wide range of phenolic and non-phenolic substrates.However,their large-scale applicability in bioremediation and water treatment is hindered by high salt content and extreme pH values of the polluted media which also affects the stability,recovery and recycling of laccase.Apart from some bacteria,laccase is abundantly present in several lignin-degrading white-rot fungi viz.Ascomycetes,Deuteromycetes,and Basidiomycetes.Recently,lac-case has been employed in the development of biosensors as a medical diagnostic tool,biofuel cells,and in bioremediation purpose to remove herbicides,pesticides,and some toxic chemicals from the soil.However,most of the enzymes including laccase are normally unstable and susceptible to lose their activity over time.This might be avoided by maintaining the activity and lengthening the enzyme's lifespan through the use of appropriate immobilization procedures.The potential of laccase immobilized biocathodes for dye decolorization in microbial fuel cells has recently been studied.Immobilized laccase nanoparticles have potential uses as biocatalyst in the bioremediation of pollutants.In addition,advanced research considering microbial laccase has been conducted for its heterologous expression along with in silico protein engineering to attain maximum enzyme activity which can be potentially applied in different biotechnological sectors.Patent related to laccase also implied that this enzyme can be used as suitable catalyst for the production of promising anti-cancer drugs and even as a significant ingredient in cosmetics.
