[Objective] To study the effects of microwave blanching treatment on POD activity and crispness in Capsicum frutescens L., and to compare the effects of microwave blanching method, normal blanching method, boiling wat...[Objective] To study the effects of microwave blanching treatment on POD activity and crispness in Capsicum frutescens L., and to compare the effects of microwave blanching method, normal blanching method, boiling water blanching and steam blanching. [Methods] In order to obtain the optimal condition for microwave blanching, response surface methodology was used to construct a quadratic regression model describing the effects of microwave power, microwave time and calcium lactate concentration on the POD activity in C. frutescens. [Results] The optimal technology was obtained based on central composite design: 525 W microwave power, 64.5 s microwave time, and 0.08% calcium lactate concentration. Under this condition, POD enzyme activity of C. frutescens was desactivated and crispness of C. frutescens was 68.77 N. [Conclusions] This research would provide references for the crispness protection and enzyme deactivation of C. frutescens.展开更多
[Objectives]This study was conducted to improve crop yield and select excellent wheat varieties.[Methods]Wheat seedlings were treated with different concentrations of NaCl solution,and the activities of superoxide dis...[Objectives]This study was conducted to improve crop yield and select excellent wheat varieties.[Methods]Wheat seedlings were treated with different concentrations of NaCl solution,and the activities of superoxide dismutase(SOD)and peroxidase(POD)and the content changes of malondialdehyde(MDA)in the leaves of seedlings were determined.A control group(distilled water)and three treatment groups(NaCl concentrations of 1,2 and 3 mmol/L)were set up.When the wheat seedlings grew to two leaves and one heart,they should be treated with different concentrations of NaCl solution(the wheat seedlings grew uniformly,and 20 ml of each NaCl concentration was used for treatment of wheat).When the wheat seedlings grew to four leaves and one heart under stress,samples were taken separately,once every 2 d,for three times,with 5 g of leaves each time.The SOD and POD activities and MDA content of seedlings in the control group and treatment groups were determined,and related protein sequences were analyzed by bioinformatics,including signal peptide prediction,transmembrane domain prediction,phosphorylation prediction and protein structure prediction.[Results]Under NaCl stress,the growth rates of seedling length and root length of wheat decreased obviously,and SOD and POD in leaves decreased,while the MDA content in leaves after treatment increased compared with the control group.SOD had no signal peptide,while POD had signal peptides and a transmembrane region.SOD and POD were different in terms of secondary and tertiary structures and the number of phosphorylation sites.[Conclusions]These results lays a solid theoretical foundation and application prospect for the study on salt tolerance mechanism of wheat seedlings in the later stage.展开更多
Chemodynamic therapy (CDT) has attracted tremendous interest in cancer therapy because it is independent of oxygen and photoirradiation. However, the therapeutic efficacy of CDT is restricted by insufficient H_(2)O_(2...Chemodynamic therapy (CDT) has attracted tremendous interest in cancer therapy because it is independent of oxygen and photoirradiation. However, the therapeutic efficacy of CDT is restricted by insufficient H_(2)O_(2) levels in tumor cells. Herein, employing endogenous GSH as a template and cationic polymeric chitosan (CS) as crosslinker and stabilizer exhibiting easy cell uptake, red luminescent gold nanoclusters (denoted CS-GSH@AuNCs) were successfully synthesized in HeLa cells. The in situ synthesized CS-GSH@AuNCs exhibited both superoxidase dismutase (SOD) and peroxidase (POD)-like activity, which could promote the production of H_(2)O_(2) from superoxide anion radicals (O_(2)^(·-)) and then ^(·)OH. The combination of GSH elimination and H_(2)O_(2) elevation boosted the generation of ^(·)OH, which could trigger cancer cell apoptosis and death. The enzyme-like activity of CS-GSH@AuNCs could be effectively activated under acidic conditions, and showed a high killing effect on tumor cells but minimal toxicity to normal cells. The developed GSH consumption and ^(·)OH promotion theranostic platform is an innovative route for enhanced CDT by the amplification of oxidative stress.展开更多
The effect of lanthanum (Ⅲ) on reactive oxygen metabolism of soybean seedlings under elevated ultraviolet-B radiation(UV-B:280~320 nm)at 0.15 and 0.45 W·cm-2 levels respectively was studied through hydropon...The effect of lanthanum (Ⅲ) on reactive oxygen metabolism of soybean seedlings under elevated ultraviolet-B radiation(UV-B:280~320 nm)at 0.15 and 0.45 W·cm-2 levels respectively was studied through hydroponics in the laboratory.Plasmolemma permeability and contents of malonadialdehyde(MDA),hydrogen peroxide(H2O2),and proline gradually increased during the imposition of UV-B radiation and subsequently decreased during recovery from UV-B stress.The dynamic tendency of catalase(CAT)activity was similar to that of the above four indices.The activity of peroxidase(POD)initially increased,then remained at a high level,and finally dropped steeply when soybean seedlings were exposed to a low dosage of UV-B radiation.However,POD activity rose throughout and declined slightly on the eleventh day when soybean seedlings were stressed by a high dosage.With the addition of La (Ⅲ) of 20 mg·L-1,the rising tendency of plasmolemma permeability and contents of MDA,H2O2,and proline were slowed down during the stress period,whereas the declining speed was accelerated during the recovery period.The activities of CAT and POD were higher than those without La (Ⅲ) in all experiments.It suggested that the regulative effect of La (Ⅲ) on antioxidant enzymes such as CAT and POD could strengthen their capacities to scavenge reactive oxygen species(ROS),decrease contents of MDA and proline,and maintain normal plasmolemma permeability.Further more,the protective potential of La (Ⅲ) was better under low UV-B radiation than under a high one.展开更多
Jatropha curcas was taken as the test material,6 concentrations including 0,25,50,100,200 and 400μmol/L AlCl3,plus 3 time gradients including 7,14 and 21 d,were set to study the effects of Al^(3+)stress on the antiox...Jatropha curcas was taken as the test material,6 concentrations including 0,25,50,100,200 and 400μmol/L AlCl3,plus 3 time gradients including 7,14 and 21 d,were set to study the effects of Al^(3+)stress on the antioxidant system of Jatropha curcas L.seedling.The results showed that with the Al^(3+)treatment being applied,protein content increased first,then decreased and finally increased with the increase of Al^(3+)concentration;the soluble sugar content increased first and then decreased with the increase of Al^(3+)concentration.Under low concentration of Al^(3+)treatment,Pro content,MDA content and POD activity of Jatropha curcas L.seedling leaves changed a little,while under high concentration of Al^(3+)treatment,Pro and MDA content of Jatropha curcas L.seedling leaves rapidly accumulated,POD activity increased and they showed a trend of increase with the increase of Al^(3+)concentration;From the perspective of Al^(3+)stress time,protein content,soluble sugar content,MDA content and POD activity increased with stress time being prolonged,while Pro content decreased with stress time being prolonged.These results indicated that the leaves of Jatropha curcas L.seedlings had certain self-protection and remediation abilities under Al^(3+)stress.展开更多
Pinellia ternata is an important medicinal plant,and its growth and development are easily threatened by high temperature.In this study,comprehensive research on physiological,cytological and transcriptional responses...Pinellia ternata is an important medicinal plant,and its growth and development are easily threatened by high temperature.In this study,comprehensive research on physiological,cytological and transcriptional responses to different levels of heat stress were conducted on a typical phenotype of P.ternata.First,P.ternata exhibited tolerance to the increased temperature,which was supported by normal growing leaves,as well as decreased and sustained photosynthetic parameters.Severe stress aggravated the damages,and P.ternata displayed an obvious leaf senescence phenotype,with significantly increased SOD and POD activities(46%and 213%).In addition,mesophyll cells were seriously damaged,chloroplast thylakoid was fuzzy,grana lamellae and stroma lamellae were obviously broken,and grana thylakoids were stacked,resulting in a dramatically declined photosynthetic rate(74.6%).Moreover,a total of 16808 genes were significantly differential expressed during this process,most of which were involved in photosynthesis,transmembrane transporter activity and plastid metabolism.The number of differentially expressed transcription factors in MYB and bHLH families was the largest,indicating that these genes might participate in heat stress response in P.ternata.These findings provide insight into the response to high temperature and facilitate the standardized cultivation of P.ternata.展开更多
Potato late blight,which is caused by Phytophthorainfestans(Mont.)de Bary,is a worldwide devastating disease for potato.It decreased yields of potato and caused unpredictable losses all over the world.Various simple s...Potato late blight,which is caused by Phytophthorainfestans(Mont.)de Bary,is a worldwide devastating disease for potato.It decreased yields of potato and caused unpredictable losses all over the world.Various simple statistical methods and forecasting models have been developed to predict and manage potato late blight.Meanwhile,there is a rising need to develop prediction models reflecting peroxidase(POD)activity,which is an important health index that varies with infection and correlated with stress resistance in plants.Thus,the aim of this research was to develop kinetic models to predict POD activity.Infection-induced changes in potato leaves stored in an artificial climate chest at 25°C were analyzed using hyperspectroscopy.Four prediction models were developed by using linear partial least squares(PLS)and nonlinear support vector machine(SVM)methods based on the full spectrum and effective wavelengths.The effective wavelengths were selected by the successive projection algorithm(SPA).In this study,the prediction model developed by means of SPA-SVM method obtained the best performance,with a Rp(correlation coefficient of prediction)value of 0.923 and a RMSEp(root mean square error of prediction)value of 24.326.Five-order kinetics models according to the prediction model were developed,and late blight disease can be predicted using this model.This study provided a theoretical basis for the prediction of latencies of late blight.展开更多
The effects of infrared-assisted hot-air drying(IR-HAD),temperature,humidity controlled hot-air drying(THC-HAD),and hot-air drying(HAD)on the drying kinetics,physicochemical properties,chlorogenic acid content and mic...The effects of infrared-assisted hot-air drying(IR-HAD),temperature,humidity controlled hot-air drying(THC-HAD),and hot-air drying(HAD)on the drying kinetics,physicochemical properties,chlorogenic acid content and microstructure of chrysanthemum were experimentally examined.The results showed that the drying time reduced with increasing air drying temperature,with IR-HAD needing the shortest drying time,followed by THC-HAD and HAD.The effective moisture diffusivities(Deff)of chrysanthemum under IR-HAD,THC-HAD,and HAD at 60℃ were 3.22×10^(-9) m^(2)/s,2.19×10^(-9) m^(2)/s,and 2.89×10^(-9) m^(2)/s,respectively.IR-HAD preserved chrysanthemum surface color better than THC-HAD and HAD,whereas the THC-HAD samples obtained higher water holding capacity(WHC),water binding capacity(WBC),and chlorogenic acid content.Additionally,peroxidase(POD)residual activity of the samples decreased with increasing blanching time.The current work provides a theoretical basis for the drying of chrysanthemum.展开更多
基金Supported by the Key Project of Chongqing City(cstc2014yykfA0030)~~
文摘[Objective] To study the effects of microwave blanching treatment on POD activity and crispness in Capsicum frutescens L., and to compare the effects of microwave blanching method, normal blanching method, boiling water blanching and steam blanching. [Methods] In order to obtain the optimal condition for microwave blanching, response surface methodology was used to construct a quadratic regression model describing the effects of microwave power, microwave time and calcium lactate concentration on the POD activity in C. frutescens. [Results] The optimal technology was obtained based on central composite design: 525 W microwave power, 64.5 s microwave time, and 0.08% calcium lactate concentration. Under this condition, POD enzyme activity of C. frutescens was desactivated and crispness of C. frutescens was 68.77 N. [Conclusions] This research would provide references for the crispness protection and enzyme deactivation of C. frutescens.
文摘[Objectives]This study was conducted to improve crop yield and select excellent wheat varieties.[Methods]Wheat seedlings were treated with different concentrations of NaCl solution,and the activities of superoxide dismutase(SOD)and peroxidase(POD)and the content changes of malondialdehyde(MDA)in the leaves of seedlings were determined.A control group(distilled water)and three treatment groups(NaCl concentrations of 1,2 and 3 mmol/L)were set up.When the wheat seedlings grew to two leaves and one heart,they should be treated with different concentrations of NaCl solution(the wheat seedlings grew uniformly,and 20 ml of each NaCl concentration was used for treatment of wheat).When the wheat seedlings grew to four leaves and one heart under stress,samples were taken separately,once every 2 d,for three times,with 5 g of leaves each time.The SOD and POD activities and MDA content of seedlings in the control group and treatment groups were determined,and related protein sequences were analyzed by bioinformatics,including signal peptide prediction,transmembrane domain prediction,phosphorylation prediction and protein structure prediction.[Results]Under NaCl stress,the growth rates of seedling length and root length of wheat decreased obviously,and SOD and POD in leaves decreased,while the MDA content in leaves after treatment increased compared with the control group.SOD had no signal peptide,while POD had signal peptides and a transmembrane region.SOD and POD were different in terms of secondary and tertiary structures and the number of phosphorylation sites.[Conclusions]These results lays a solid theoretical foundation and application prospect for the study on salt tolerance mechanism of wheat seedlings in the later stage.
基金supported by the National Natural Science Foundation of China (No. 22074007)。
文摘Chemodynamic therapy (CDT) has attracted tremendous interest in cancer therapy because it is independent of oxygen and photoirradiation. However, the therapeutic efficacy of CDT is restricted by insufficient H_(2)O_(2) levels in tumor cells. Herein, employing endogenous GSH as a template and cationic polymeric chitosan (CS) as crosslinker and stabilizer exhibiting easy cell uptake, red luminescent gold nanoclusters (denoted CS-GSH@AuNCs) were successfully synthesized in HeLa cells. The in situ synthesized CS-GSH@AuNCs exhibited both superoxidase dismutase (SOD) and peroxidase (POD)-like activity, which could promote the production of H_(2)O_(2) from superoxide anion radicals (O_(2)^(·-)) and then ^(·)OH. The combination of GSH elimination and H_(2)O_(2) elevation boosted the generation of ^(·)OH, which could trigger cancer cell apoptosis and death. The enzyme-like activity of CS-GSH@AuNCs could be effectively activated under acidic conditions, and showed a high killing effect on tumor cells but minimal toxicity to normal cells. The developed GSH consumption and ^(·)OH promotion theranostic platform is an innovative route for enhanced CDT by the amplification of oxidative stress.
基金Project supported by the National Natural Science Foundation of China(30570323)the Foundation of State Developingand Reforming Committee(IFZ20051210)
文摘The effect of lanthanum (Ⅲ) on reactive oxygen metabolism of soybean seedlings under elevated ultraviolet-B radiation(UV-B:280~320 nm)at 0.15 and 0.45 W·cm-2 levels respectively was studied through hydroponics in the laboratory.Plasmolemma permeability and contents of malonadialdehyde(MDA),hydrogen peroxide(H2O2),and proline gradually increased during the imposition of UV-B radiation and subsequently decreased during recovery from UV-B stress.The dynamic tendency of catalase(CAT)activity was similar to that of the above four indices.The activity of peroxidase(POD)initially increased,then remained at a high level,and finally dropped steeply when soybean seedlings were exposed to a low dosage of UV-B radiation.However,POD activity rose throughout and declined slightly on the eleventh day when soybean seedlings were stressed by a high dosage.With the addition of La (Ⅲ) of 20 mg·L-1,the rising tendency of plasmolemma permeability and contents of MDA,H2O2,and proline were slowed down during the stress period,whereas the declining speed was accelerated during the recovery period.The activities of CAT and POD were higher than those without La (Ⅲ) in all experiments.It suggested that the regulative effect of La (Ⅲ) on antioxidant enzymes such as CAT and POD could strengthen their capacities to scavenge reactive oxygen species(ROS),decrease contents of MDA and proline,and maintain normal plasmolemma permeability.Further more,the protective potential of La (Ⅲ) was better under low UV-B radiation than under a high one.
文摘Jatropha curcas was taken as the test material,6 concentrations including 0,25,50,100,200 and 400μmol/L AlCl3,plus 3 time gradients including 7,14 and 21 d,were set to study the effects of Al^(3+)stress on the antioxidant system of Jatropha curcas L.seedling.The results showed that with the Al^(3+)treatment being applied,protein content increased first,then decreased and finally increased with the increase of Al^(3+)concentration;the soluble sugar content increased first and then decreased with the increase of Al^(3+)concentration.Under low concentration of Al^(3+)treatment,Pro content,MDA content and POD activity of Jatropha curcas L.seedling leaves changed a little,while under high concentration of Al^(3+)treatment,Pro and MDA content of Jatropha curcas L.seedling leaves rapidly accumulated,POD activity increased and they showed a trend of increase with the increase of Al^(3+)concentration;From the perspective of Al^(3+)stress time,protein content,soluble sugar content,MDA content and POD activity increased with stress time being prolonged,while Pro content decreased with stress time being prolonged.These results indicated that the leaves of Jatropha curcas L.seedlings had certain self-protection and remediation abilities under Al^(3+)stress.
基金supported by the Scientific and Technological Innovation Project of China Academy of Chinese Medical Sciences(No.CI2021A04106)the Fundamental Research Funds for the Central Public Welfare Research Institutes of China(Nos.ZXKT21026 and ZZ15-YQ-033)the Major Special Project of Scientific and Technological Cooperation of Bijie City(2021-02).
文摘Pinellia ternata is an important medicinal plant,and its growth and development are easily threatened by high temperature.In this study,comprehensive research on physiological,cytological and transcriptional responses to different levels of heat stress were conducted on a typical phenotype of P.ternata.First,P.ternata exhibited tolerance to the increased temperature,which was supported by normal growing leaves,as well as decreased and sustained photosynthetic parameters.Severe stress aggravated the damages,and P.ternata displayed an obvious leaf senescence phenotype,with significantly increased SOD and POD activities(46%and 213%).In addition,mesophyll cells were seriously damaged,chloroplast thylakoid was fuzzy,grana lamellae and stroma lamellae were obviously broken,and grana thylakoids were stacked,resulting in a dramatically declined photosynthetic rate(74.6%).Moreover,a total of 16808 genes were significantly differential expressed during this process,most of which were involved in photosynthesis,transmembrane transporter activity and plastid metabolism.The number of differentially expressed transcription factors in MYB and bHLH families was the largest,indicating that these genes might participate in heat stress response in P.ternata.These findings provide insight into the response to high temperature and facilitate the standardized cultivation of P.ternata.
基金This research was supported by the Natural Science Foundation of China(31671965)the project of Key Laboratory of Agricultural Internet of Things,Ministry of Agriculture,China(2017001).
文摘Potato late blight,which is caused by Phytophthorainfestans(Mont.)de Bary,is a worldwide devastating disease for potato.It decreased yields of potato and caused unpredictable losses all over the world.Various simple statistical methods and forecasting models have been developed to predict and manage potato late blight.Meanwhile,there is a rising need to develop prediction models reflecting peroxidase(POD)activity,which is an important health index that varies with infection and correlated with stress resistance in plants.Thus,the aim of this research was to develop kinetic models to predict POD activity.Infection-induced changes in potato leaves stored in an artificial climate chest at 25°C were analyzed using hyperspectroscopy.Four prediction models were developed by using linear partial least squares(PLS)and nonlinear support vector machine(SVM)methods based on the full spectrum and effective wavelengths.The effective wavelengths were selected by the successive projection algorithm(SPA).In this study,the prediction model developed by means of SPA-SVM method obtained the best performance,with a Rp(correlation coefficient of prediction)value of 0.923 and a RMSEp(root mean square error of prediction)value of 24.326.Five-order kinetics models according to the prediction model were developed,and late blight disease can be predicted using this model.This study provided a theoretical basis for the prediction of latencies of late blight.
基金This work was supported by China Agriculture Research System(CARS-21).
文摘The effects of infrared-assisted hot-air drying(IR-HAD),temperature,humidity controlled hot-air drying(THC-HAD),and hot-air drying(HAD)on the drying kinetics,physicochemical properties,chlorogenic acid content and microstructure of chrysanthemum were experimentally examined.The results showed that the drying time reduced with increasing air drying temperature,with IR-HAD needing the shortest drying time,followed by THC-HAD and HAD.The effective moisture diffusivities(Deff)of chrysanthemum under IR-HAD,THC-HAD,and HAD at 60℃ were 3.22×10^(-9) m^(2)/s,2.19×10^(-9) m^(2)/s,and 2.89×10^(-9) m^(2)/s,respectively.IR-HAD preserved chrysanthemum surface color better than THC-HAD and HAD,whereas the THC-HAD samples obtained higher water holding capacity(WHC),water binding capacity(WBC),and chlorogenic acid content.Additionally,peroxidase(POD)residual activity of the samples decreased with increasing blanching time.The current work provides a theoretical basis for the drying of chrysanthemum.