The changes of hydrogen peroxide （H2O2） metabolism and antioxidant enzyme activities in a hybrid poplar （Populus simonii xp. pyramidalis ＇Opera 8277＇） in response to rnechanical damage （MD） and herbivore wound...The changes of hydrogen peroxide （H2O2） metabolism and antioxidant enzyme activities in a hybrid poplar （Populus simonii xp. pyramidalis ＇Opera 8277＇） in response to rnechanical damage （MD） and herbivore wounding （HW） were investigated to determine whether H2O2 could function as the secondary messenger in the signaling of systemic resistance. Results show that H2O2 was generated in wounded leaves through MD and HW treatments and systemically in unwounded leaves around the wounded leaves. The activities of antioxidant enzymes such as superoxide dismutase （SOD）, catalase （CAT） and ascorbate peroxidase （APX） were also enhanced. However, the H2O2 accumulation and antioxidant enzyme activities were inhibited in MD leaves through the pretreatment with DPI （which is a specific inhibitor of NADPH oxidase）. The results of this study suggest that H2O2 could be systemically induced by MD and HW treatments, and H2O2 metabolism was closely related to the change in SOD, APX and CAT activities. A high level of antioxidant enzymes could decrease membrane lipid peroxidation levels and effectively induce plant defense responses.展开更多
Cold acclimation is associated with many metabolic changes that lead to an increase of freezing tolerance. In order to investigate the biochemical process of cold acclimation in Ammopiptanthus mongolicus, seedlings we...Cold acclimation is associated with many metabolic changes that lead to an increase of freezing tolerance. In order to investigate the biochemical process of cold acclimation in Ammopiptanthus mongolicus, seedlings were acclimated at 2℃ under 16-h photoperiod （150 μmol·m^-2·s^-1 photosynthetically active radiation） for 14 d. Freezing tolerance in seedlings increased after 14 d of cold-hardening. Contents of protein, proline and solute carbohydrate in cotyledon increased after cold acclimation. Patterns of isozymes of superoxide dismutase （SOD）, peroxidase, catalase and polyphenol oxidase （PPO） were investigated. The activities of SOD, peroxidase and PPO in cold acclimated plants were increased during cold-hardening. We deduced that compatible solutes and antioxidant enzymes play important roles in development of freezing tolerance during cold acclimation in this evergreen woody plant.展开更多
Chinese peony(Paeonia lactiflora Pall.)is both medicinally and aesthetically beneficial.Powdery mildew is a common fungal disease that seriously jeopardizes the value of numerous species,including peonies as a crop.In...Chinese peony(Paeonia lactiflora Pall.)is both medicinally and aesthetically beneficial.Powdery mildew is a common fungal disease that seriously jeopardizes the value of numerous species,including peonies as a crop.In order to provide a basis for the prevention and treatment of peony powdery mildew,we examined the microbial diversity,the malondialdehyde(MDA)concentrations and antioxidant enzyme activities of peony leaves infected with three levels of powdery mildew to determine any modifications to the leaf's antioxidant enzyme systems and microbial community structure following the onset of disease.The results show that the MDA content rose as the degree of infection became worse.Antioxidant enzyme activity rose and then declined.Following the initiation of powdery mildew,fungal community diversity decreased,whereas there was not any appreciable change in bacterial communities according to microbial diversity sequencing.The relative abundance of more than half of fungal species decreased,with the bacterial genera displaying both abundant and diminished communities with less pronounced alterations in their community structure after the disease spread.Significant different taxa that were critical to the organization of each microbiome were found.Correlation analysis showed that the relative abundance of powdery mildew pathogenic fungal genus Erysiphe was correlated with those of 11 fungal genera and one bacterial genus.Among them,Aureobasidium,Neosetophoma and Sclerostagonospora showed significant positive correlations with Erysiphe and MDA.展开更多
Ar^＋ ion beam with low energy of 30 keV was implanted into liquorice （Glycyrrhiza uralensis Fisch） seeds at the doses of 0, 600, 900 and 1200 × （2.6 × 10^13） ions/cm^2, respectively. The seeds were sowe...Ar^＋ ion beam with low energy of 30 keV was implanted into liquorice （Glycyrrhiza uralensis Fisch） seeds at the doses of 0, 600, 900 and 1200 × （2.6 × 10^13） ions/cm^2, respectively. The seeds were sowed in pots and after one month the plants were subjected to different drought conditions for two months. Then the plants＇ morphological and physiological characteristics, antioxidation enzymes and levels of endogenous hormones were investigated. The results showed that ion implantation at a proper dose can greatly enhance the liquorice seedlings＇ resistance against drought stress.展开更多
Bacillus subtilis JZXJ-7 isolated from shrimp paste can significantly degrade histamine under salt stress but the mechanism is unclear.This study aims to evaluate the effect of 170 and 340 mmol/L Na Cl on B.subtilis J...Bacillus subtilis JZXJ-7 isolated from shrimp paste can significantly degrade histamine under salt stress but the mechanism is unclear.This study aims to evaluate the effect of 170 and 340 mmol/L Na Cl on B.subtilis JZXJ-7 growth,histamine degradation,antioxidant enzymes(catalase(CAT),superoxide dismutase(SOD)and glutathione S-transferase(GST))activities and Na^(+)/K^(+)-ATPase activity.Furthermore,comparative metabolomics was used to investigate histamine biodegradation mechanism by B.subtilis JZXJ-7 subjected to salt stress.Both 170 and 340 mmol/L Na Cl promoted B.subtilis JZXJ-7 growth in late stages of reproduction(32-48 h),increased h istamine degradation rate by 64.85%and 79.87%(P<0.05),Na^(+)/K^(+)-ATPase activity to 6.28(P<0.05)and 11.63 U/mg(P<0.01)respectively.N a Cl treatment significantly increased the activities of CAT,GST and SOD(P<0.05),a mino acids and its metabolites(33.39%),benzene and substituted derivatives(12.05%),heterocyclic compounds(10.62%),organic acids and derivatives(9.75%),aldehydes,ketones,esters(5.59%)and nucleotides and its metabolites(4.58%).Metabolite set enrichment analysis revealed Na Cl induced differential metabolic pathways of D-glutamine,D-glutamate,L-arginine,L-proline,histidine and glycerophospholipids,L-lysine degradation,and aminoacyl-t RNA biosynthesis.Exposure to 340 mmol/L Na Cl up-regulated carbohydrate,glutathione and glycerophospholipid metabolism.The new insights into the mechanism of salt stress to promote B.subtilis JZJX-7 growth,energy metabolic pathways and to degrade histamine provide the theoretical basis for application of B.subtilis JZXJ-7 in food fermentation industry.展开更多
文摘The changes of hydrogen peroxide （H2O2） metabolism and antioxidant enzyme activities in a hybrid poplar （Populus simonii xp. pyramidalis ＇Opera 8277＇） in response to rnechanical damage （MD） and herbivore wounding （HW） were investigated to determine whether H2O2 could function as the secondary messenger in the signaling of systemic resistance. Results show that H2O2 was generated in wounded leaves through MD and HW treatments and systemically in unwounded leaves around the wounded leaves. The activities of antioxidant enzymes such as superoxide dismutase （SOD）, catalase （CAT） and ascorbate peroxidase （APX） were also enhanced. However, the H2O2 accumulation and antioxidant enzyme activities were inhibited in MD leaves through the pretreatment with DPI （which is a specific inhibitor of NADPH oxidase）. The results of this study suggest that H2O2 could be systemically induced by MD and HW treatments, and H2O2 metabolism was closely related to the change in SOD, APX and CAT activities. A high level of antioxidant enzymes could decrease membrane lipid peroxidation levels and effectively induce plant defense responses.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.30671476 and 30271067).
文摘Cold acclimation is associated with many metabolic changes that lead to an increase of freezing tolerance. In order to investigate the biochemical process of cold acclimation in Ammopiptanthus mongolicus, seedlings were acclimated at 2℃ under 16-h photoperiod （150 μmol·m^-2·s^-1 photosynthetically active radiation） for 14 d. Freezing tolerance in seedlings increased after 14 d of cold-hardening. Contents of protein, proline and solute carbohydrate in cotyledon increased after cold acclimation. Patterns of isozymes of superoxide dismutase （SOD）, peroxidase, catalase and polyphenol oxidase （PPO） were investigated. The activities of SOD, peroxidase and PPO in cold acclimated plants were increased during cold-hardening. We deduced that compatible solutes and antioxidant enzymes play important roles in development of freezing tolerance during cold acclimation in this evergreen woody plant.
基金supported by grants from“Cataloguing,flora study and database establishment of mini-type fungi in Northeast Asia”from the Northeast Asia Biodiversity Research Center。
文摘Chinese peony(Paeonia lactiflora Pall.)is both medicinally and aesthetically beneficial.Powdery mildew is a common fungal disease that seriously jeopardizes the value of numerous species,including peonies as a crop.In order to provide a basis for the prevention and treatment of peony powdery mildew,we examined the microbial diversity,the malondialdehyde(MDA)concentrations and antioxidant enzyme activities of peony leaves infected with three levels of powdery mildew to determine any modifications to the leaf's antioxidant enzyme systems and microbial community structure following the onset of disease.The results show that the MDA content rose as the degree of infection became worse.Antioxidant enzyme activity rose and then declined.Following the initiation of powdery mildew,fungal community diversity decreased,whereas there was not any appreciable change in bacterial communities according to microbial diversity sequencing.The relative abundance of more than half of fungal species decreased,with the bacterial genera displaying both abundant and diminished communities with less pronounced alterations in their community structure after the disease spread.Significant different taxa that were critical to the organization of each microbiome were found.Correlation analysis showed that the relative abundance of powdery mildew pathogenic fungal genus Erysiphe was correlated with those of 11 fungal genera and one bacterial genus.Among them,Aureobasidium,Neosetophoma and Sclerostagonospora showed significant positive correlations with Erysiphe and MDA.
基金High Tech Research and Development(863)Program(Nos.2002AA327070,2004AA32G060)
文摘Ar^＋ ion beam with low energy of 30 keV was implanted into liquorice （Glycyrrhiza uralensis Fisch） seeds at the doses of 0, 600, 900 and 1200 × （2.6 × 10^13） ions/cm^2, respectively. The seeds were sowed in pots and after one month the plants were subjected to different drought conditions for two months. Then the plants＇ morphological and physiological characteristics, antioxidation enzymes and levels of endogenous hormones were investigated. The results showed that ion implantation at a proper dose can greatly enhance the liquorice seedlings＇ resistance against drought stress.
基金supported by the National Key R&D Program of China(2019YFD0901702)National Natural Science Foundation of China(32201929,32202134)+3 种基金2025 Guangdong Basic and Applied Basic Research Foundation of Natural Science Foundation Project(2025A1515011748)High-level Talent Project of Lingnan Normal University(ZL2415)China Postdoctoral Science Foundation(2022M712625)2021 and 2022 Chongqing Postdoctoral Special Funding Project。
文摘Bacillus subtilis JZXJ-7 isolated from shrimp paste can significantly degrade histamine under salt stress but the mechanism is unclear.This study aims to evaluate the effect of 170 and 340 mmol/L Na Cl on B.subtilis JZXJ-7 growth,histamine degradation,antioxidant enzymes(catalase(CAT),superoxide dismutase(SOD)and glutathione S-transferase(GST))activities and Na^(+)/K^(+)-ATPase activity.Furthermore,comparative metabolomics was used to investigate histamine biodegradation mechanism by B.subtilis JZXJ-7 subjected to salt stress.Both 170 and 340 mmol/L Na Cl promoted B.subtilis JZXJ-7 growth in late stages of reproduction(32-48 h),increased h istamine degradation rate by 64.85%and 79.87%(P<0.05),Na^(+)/K^(+)-ATPase activity to 6.28(P<0.05)and 11.63 U/mg(P<0.01)respectively.N a Cl treatment significantly increased the activities of CAT,GST and SOD(P<0.05),a mino acids and its metabolites(33.39%),benzene and substituted derivatives(12.05%),heterocyclic compounds(10.62%),organic acids and derivatives(9.75%),aldehydes,ketones,esters(5.59%)and nucleotides and its metabolites(4.58%).Metabolite set enrichment analysis revealed Na Cl induced differential metabolic pathways of D-glutamine,D-glutamate,L-arginine,L-proline,histidine and glycerophospholipids,L-lysine degradation,and aminoacyl-t RNA biosynthesis.Exposure to 340 mmol/L Na Cl up-regulated carbohydrate,glutathione and glycerophospholipid metabolism.The new insights into the mechanism of salt stress to promote B.subtilis JZJX-7 growth,energy metabolic pathways and to degrade histamine provide the theoretical basis for application of B.subtilis JZXJ-7 in food fermentation industry.
