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Effect of powdery mildew on interleaf microbial communities and leaf antioxidant enzyme systems
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作者 Xinbo Ma Zhanbin Wang +1 位作者 Run Liu Yibing Jiang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1535-1547,共13页
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
关键词 Powdery mildew Disease level Interleaf microbial diversity Antioxidant enzyme
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Effects of two kinds of transgenic poplar on protective enzymes system in the midgut of larvae of American white moth 被引量:10
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作者 丁双阳 孟秀芹 李学锋 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第2期119-122,147,共4页
The leaves of Bt (Bacillus thuringiensis) transgenic poplar (Populus nigra L.) and CpTI (Cowpea trypsin inhibitor) transgenic poplar ((P. tomentosa×P. bolleana)×P. Tomentosa) were taken to feed the 4th-5th-i... The leaves of Bt (Bacillus thuringiensis) transgenic poplar (Populus nigra L.) and CpTI (Cowpea trypsin inhibitor) transgenic poplar ((P. tomentosa×P. bolleana)×P. Tomentosa) were taken to feed the 4th-5th-instar larvae of American white moth (Hyphantria cunea (Drury)) for determination of the activities of the protective enzyme system inside larvae’s body. The physiological and biochemical effects of the transgenic poplars on the larvae were studied. The results showed that the two kinds of transgenic poplars had similar effects on the protective enzyme system in the midgut of larvae. The activities of superoxide dismutase, catalase, and peroxidase in midgut of the larvae increased gradually, reached the highest value at a certain time, and then decreased suddenly. For the larvae that were fed with the leaves of Bt transgenic poplar, the peak value of superoxide dismutase and catalase presented at the time of 24-h feeding, while the peak of peroxidase took place at the time of 12-h feeding. The activities of these protective enzymes for the larvae that were fed with leaves of CpTI transgenic poplar peaked 12 h later than that of those fed with leaves of Bt transgenic poplar. The comparison of activities of the protective enzymes was also carried out between the larvae with different levels of intoxication. It was found that the activities of protective enzyme of the seriously intoxicant larvae were higher than that of the lightly intoxicant larvae. This difference was more obvious in the group treated with CpTI transgenic poplar. 展开更多
关键词 Transgenic poplar American white moth Protective enzyme system
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Responses of soil enzymes to long-term CO_2 enrichment in forest ecosystems of Changbai Mountains
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作者 辛丽花 韩士杰 +2 位作者 李莉 周玉梅 郑俊强 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第2期119-122,共4页
A study was conducted to determine the responses of soil enzymes (invertase, polyphenol oxidase, catalase, and dehydrogenase) to long-term CO2 enrichment at the Research Station of Changbai Mountain Forest Ecosystem... A study was conducted to determine the responses of soil enzymes (invertase, polyphenol oxidase, catalase, and dehydrogenase) to long-term CO2 enrichment at the Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences (42°24'N, 128°28'E; 738 m in elevation) in the northeast China during 1999-2006. Three treatments of the CO2 enrichment, designed as 500 μmol·mol-1 CO2 open-top chamber (OTC), ambient control chamber and unchambered field (approx. 370 μmol·mol^-1CO2), were conducted with Pinus koraiensis and Pinus sylvestriformis tree species. Soil sampling was made and analyzed separately in spring, summer and autumn in 2006 after the soil enzymes were exposed to elevated CO2 concentration (500 μmol·mol^-1) for eight growing seasons. Results showed that, at elevated CO2 concentration (500 μmol·mol^-1), the activities of invertase (except for the summer samples of P. koraiensis) presented a remarkable decline in all growing seasons, while the activities of dehydrogenase had an increase but only part of the results was remarkable; the activities of polyphenol oxidase in P. sylvestriformis rhizosphere showed a remarkable decrease; the catalase activities increased in spring, while in turn were decline in other seasons. This study also revealed that the soil enzyme activities are significantly correlated with the tree species under the CO2 enhancement. 展开更多
关键词 CO2 concentration CO2 enrichment Soil enzymes INVERTASE DEHYDROGENASE CATALASE Polyphenol oxidase
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Electro-enzyme coupling systems for selective reduction of CO_(2) 被引量:1
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作者 Yuman Guo Xueming Hong +1 位作者 Ziman Chen Yongqin Lv 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期140-162,I0005,共24页
To address the energy crisis and alleviate the rising level of CO_(2)in the atmosphere,various CO_(2)capture and utilization(CCU)technologies have been developed.The use of electro-enzyme coupling systems is a promisi... To address the energy crisis and alleviate the rising level of CO_(2)in the atmosphere,various CO_(2)capture and utilization(CCU)technologies have been developed.The use of electro-enzyme coupling systems is a promising strategy for the sustainable production of fuels,chemicals and materials using CO_(2)as the feedstock.In this review,the recent progresses in the development of electro-enzyme coupling systems for the selective reduction of CO_(2)are systematically summarized.We first provide a brief background about the significance and challenges in the direct conversion of CO_(2)into value-added chemicals.Next,we describe the materials and strategies in the design of electrodes,as well as the common enzymes used in the electro-enzyme coupling systems.Then,we focus on the state-of-the-art routes for the electro-enzyme coupling conversion of CO_(2)into a variety of compounds(formate,CO,methanol,C≥2chemicals)by a single enzyme or multienzyme systems.The emerging approaches and materials used for the construction of electro-enzyme coupling systems to enhance the electron transfer efficiency and the catalytic activity/stability are highlighted.The main challenges and perspectives in the integration of enzymatic and electrochemical strategies are also discussed. 展开更多
关键词 Electro-enzyme coupling CO_(2)reduction ELECTROCHEMISTRY enzyme Electron transfer
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Double enzyme mimetic activities of multifunctional Ag nanoparticle-decorated Co_(3)V_(2)O_(8)hollow hexagonal prismatic pencils for application in colorimetric sensors and disinfection
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作者 Ying Gao Peng Ju +4 位作者 Yu Zhang Yuxin Zhang Xiaofan Zhai Jizhou Duan Baorong Hou 《Nano Materials Science》 EI CAS CSCD 2024年第2期244-255,共12页
Since the catalytic activity of most nanozymes is still far lower than the corresponding natural enzymes,there is urgent need to discover novel highly efficient enzyme-like materials.In this work,Co_(3)V_(2)O_(8)with ... Since the catalytic activity of most nanozymes is still far lower than the corresponding natural enzymes,there is urgent need to discover novel highly efficient enzyme-like materials.In this work,Co_(3)V_(2)O_(8)with hollow hexagonal prismatic pencil structures were prepared as novel artificial enzyme mimics.They were then decorated by photo-depositing Ag nanoparticles(Ag NPs)on the surface to further improve its catalytic activities.The Ag NPs decorated Co_(3)V_(2)O_(8)(ACVPs)showed both excellent oxidase-and peroxidase-like catalytic activities.They can oxidize the colorless 3,3’,5,5’-tetramethylbenzidine rapidly to induce a blue change.The enhanced enzyme mimetic activities can be attributed to the surface plasma resonance(SPR)effect of Ag NPs as well as the synergistic catalytic effect between Ag NPs and Co_(3)V_(2)O_(8),accelerating electron transfer and promoting the catalytic process.ACVPs were applied in constructing a colorimetric sensor,validating the occurrence of the Fenton reaction,and disinfection,presenting favorable catalytic performance.The enzyme-like catalytic mechanism was studied,indicating the chief role of⋅O_(2)-radicals in the catalytic process.This work not only discovers a novel functional material with double enzyme mimetic activity but also provides a new insight into exploiting artificial enzyme mimics with highly efficient catalytic ability. 展开更多
关键词 Co_(3)V_(2)O_(8) Ag NPs enzyme mimetic Colorimetric sensor DISINFECTION
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Effects of long-term elevated CO_2 on N_2-fixing,denitrifying and nitrifying enzyme activities in forest soils under Pinus sylvestriformis in Changbai Mountain 被引量:4
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作者 郑俊强 韩士杰 +2 位作者 任飞荣 周玉梅 张岩 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第4期283-287,共5页
A study was conducted to determine the effects of elevated CO2 on soil N process at Changbai Mountain in Jilin Province, northeastern China (42°24"N, 128°06"E, and 738 m elevation). A randomized complete... A study was conducted to determine the effects of elevated CO2 on soil N process at Changbai Mountain in Jilin Province, northeastern China (42°24"N, 128°06"E, and 738 m elevation). A randomized complete block design of ambient and elevated CO2 was established in an open-top chamber facility in the spring of 1999. Changpai Scotch pine (Pinus sylvestris var. sylvestriformis seeds were sowed in May, 1999 and CO2 fumigation treatments began after seeds germination. In each year, the exposure started at the end of April and stopped at the end of October. Soil samples were collected in June and August 2006 and in June 2007, and soil nitrifying, denitrifying and N2-fixing enzyme activities were measured. Results show that soil nitrifying enzyme activities (NEA) in the 5-10 cm soil layer were significantly increased at elevated CO2 by 30.3% in June 2006, by 30.9% in August 2006 and by 11.3% in June 2007. Soil denitrifying enzyme activities (DEA) were significantly decreased by elevated CO2 treatment in June 2006 (P 〈 0.012) and August 2006 (P 〈 0.005) samplings in our study; no significant difference was detected in June 2007, and no significant changes in N2-fixing enzyme activity were found. This study suggests that elevated CO2 can alter soil nitrifying enzyme and denitrifying enzyme activities. 展开更多
关键词 elevated CO2 forest soil nitrifying enzyme denitrifying enzyme N2-fixing enzyme
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Effects of mechanical damage and herbivore wounding on H2O2 metabolism and antioxidant enzyme activities in hybrid poplar leaves 被引量:12
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作者 安钰 沈应柏 张志翔 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期156-160,I0003,共6页
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
关键词 antioxidant enzymes herbivore wound induced resistance mechanical damage reactive oxygen species
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Wettability changes of wheat straw treated with chemicals and enzymes 被引量:7
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作者 SHEN Jiang-hua LIU Zhi-ming LI Jing NIU Jing 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第1期107-110,共4页
A study was conducted to test wettability changes of the wheat straw treated with different methods for the preparation of wheat straw particle board. The wheat straws were separately sprayed with two chemicals (0.6%... A study was conducted to test wettability changes of the wheat straw treated with different methods for the preparation of wheat straw particle board. The wheat straws were separately sprayed with two chemicals (0.6% NaOH, 0.3% H2O2) and three enzymes (lipase, xylanase, cellulase). The contact angle between water and the surface of wheat straw was measured and the spreading-penetration parameters (K-values) were also calculated with wetting model. The surfaces of treated wheat straw and control sample were scanned by means of Micro-FTIR, and their peaks arrangements were analyzed. The surface morphologies of treated wheat straw and control sample were also observed by SEM. Chemical etching was found on the exterior surfaces of the straws treated separately with 0.6% NaOH and 0.3% H2O2; furthermore, the spreading-penetration parameters (K-values) of the distilled water on the exterior surfaces of the treated wheat straw along the grain were higher than that of control. The wettability of exterior surfaces of the wheat straws treated separately with lipase, xylanase and cellulose were improved after treating for seven days, and among the three enzymes treatments, the lipase treatment showed best result. The lipase treatment and NaOH treatment were determined as better methods for improving the wettability of wheat straw surfaces. However, in the economic aspect, NaOH treatment was more practical and easier in the pretreatment for the manufacture of straw particle board. 展开更多
关键词 wheat straw WETTABILITY contact angle CHEMICALS enzyme
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Insights into seasonal variation of litter decomposition and related soil degradative enzyme activities in subtropical forest in China 被引量:9
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作者 WANG Cong-yan Lü Yan-na +2 位作者 WANG Lei LIU Xue-yan TIAN Xingjun 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第4期683-689,共7页
We used a litterbag method to investigate litter decomposition and related soil degradative enzyme activities across four seasons in a broad-leaved forest and a coniferous forest on Zijin Mountain in sub-tropical Chin... We used a litterbag method to investigate litter decomposition and related soil degradative enzyme activities across four seasons in a broad-leaved forest and a coniferous forest on Zijin Mountain in sub-tropical China. Across four seasons, we quantified litter mass losses, soil pH values, and related soil degradative enzyme activities. Litter decomposition rates differed significantly by season. Litter decomposi- tion rates of broadleaf forest leaves were higher than for coniferous for- ests needles across four seasons, and maximal differences in litter de- composition rates between the two litter types were found in spring. 展开更多
关键词 broad-leaved forest coniferous forest litter decomposition soil degradative enzyme
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Photosynthesis, chilling acclimation and the response of antioxidant enzymes to chilling stress in mulberry seedlings 被引量:6
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作者 Xiaojia Liu Nan Xu +3 位作者 Yining Wu Jinbo li Haixiu Zhong Huihui Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2021-2029,共9页
This study investigates the effects of cold-acclimation in conferring chilling tolerance in seedlings of the mulberry(Morus alba) variety ‘Qiuyu’. Changes in photosynthesis and antioxidant enzymes in chilling acclim... This study investigates the effects of cold-acclimation in conferring chilling tolerance in seedlings of the mulberry(Morus alba) variety ‘Qiuyu’. Changes in photosynthesis and antioxidant enzymes in chilling acclimatized(CA), and non-acclimatized(NA) seedlings were recorded during chilling stress(3 °C) and a recovery period(25 °C) each for 3 days. The results showed that CA plants had higher net photosynthetic rates(P_n), stomatal conductance(G_s), and maximum photochemical efficiency of photosystem Ⅱ(F_v/F_m) in response to chilling stress compared to NA. The seedlings maintained the same trends during the recovery stage. The responses of Q_A reduction degree (1-q_P) and prime electronic transfer rates(F_o) were lower in acclimatized than in non-acclimatized seedlings. Low-temperature acclimation and chilling stress also caused an increase in leaf proline and soluble sugar contents. Leaf malondialdehyde levels were significantly lower while ascorbate peroxidase(APX) activity was significantly higher in acclimatized seedlings, suggesting that elevated osmolytes and APX confer resistance to chilling temperatures. In this study on the response of mulberry seedlings to chilling stress, we also looked at the recovery process. The response to chilling determines whether mulberry leaves can survive under cold temperatures, while the recovery process determines whether photosynthesis can recover as soon as possible to avoid any secondary damage. 展开更多
关键词 Antioxidant enzyme CHILLING ACCLIMATION CHILLING tolerance MULBERRY PHOTOSYNTHESIS
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Rhizosphere and bulk soil enzyme activities in a Nothotsuga longibracteata forest in the Tianbaoyan National Nature Reserve,Fujian Province,China 被引量:8
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作者 Shihong Xiao Huiming You +8 位作者 Weibin You Jinshan Liu Changtang Cai Jianqin Wu Zhirong Ji Shihua Zhan Zhesen Hu Zhongrui Zhang Dongjin He 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第3期521-528,共8页
The rhizosphere, distinct from bulk soil, is defined as the volume of soil around living roots and influenced by root activities. We investigated protease, invertase, cellulase, urease, and acid phosphatase activities... The rhizosphere, distinct from bulk soil, is defined as the volume of soil around living roots and influenced by root activities. We investigated protease, invertase, cellulase, urease, and acid phosphatase activities in rhizosphere and bulk soils of six Nothotsuga longibracteata forest communities within Tianbaoyan National Nature Reserve, including N. longibracteata + either Phyllostachys pubescens, Schima superba, Rhododendron simiarum, Cunninghamia lanceolata, or Cyclobalanopsis glauca, and N. longibracteata pure forest. Rhizosphere soils possessed higher protease, invertase, cellulase, urease, and acid phosphatase activities than bulk soils. The highest invertase, urease, and acid phosphatase activities were observed in rhizosphere samples of N. longibracteata + S. superba. Protease was highest in the N. longibracteata + R. simiarum rhizosphere, while cellulase was highest in the pure N. longibracteata forest rhizosphere. All samples exhibited obvious rhizosphere effects on enzyme activities with a significant linear correlation between acid phosphatase and cellulase activities (p 〈 0.05) in rhizosphere soils and between protease and acid phosphatase activities (p 〈 0.05) in bulk soils. A principal component analysis, correlating 13 soil chemical properties indices relevant to enzyme activities, showed that protease, invertase, acid phosphatase, total N, and cellulase were the most important variables impacting rhizosphere soil quality. 展开更多
关键词 Bulk soil enzyme activities Rhizosphere soil Tianbaoyan National Nature Reserve Nothotsuga longibracteata
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Ecological effects of atmospheric nitrogen deposition on soil enzyme activity 被引量:11
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作者 WANG Cong-yan Lv Yan-na +1 位作者 LIU Xue-yan WANG Lei 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第1期109-114,共6页
The continuing increase in human activities is causing global changes such as increased deposition of atmospheric nitrogen. There is considerable interest in understanding the effects of increasing atmospheric nitroge... The continuing increase in human activities is causing global changes such as increased deposition of atmospheric nitrogen. There is considerable interest in understanding the effects of increasing atmospheric nitrogen deposition on soil enzyme activities, specifically in terms of global nitrogen cycling and its potential future contribution to global climate change. This paper summarizes the ecological effects of atmospheric nitrogen deposition on soil enzyme activities, including size-effects, stage-effects, site-effects, and the effects of different levels and forms of atmospheric nitrogen deposition. We discuss needs for further research on the relationship between atmospheric nitrogen deposition and soil enzymes. 展开更多
关键词 global change nitrogen deposition soil enzyme activities
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Changes in the biochemical composition and enzyme activity during dormancy release of Cyclocarya paliurus seeds 被引量:12
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作者 Fang Sheng-zuo Wang Jia-yuan 《Forestry Studies in China》 CAS 2007年第1期7-13,共7页
Cyclocarya paliurus is only propagated from seeds which have pronounced dormancy. Overcoming seed dormancy is an important component of efficient and cost-effective seedling production of Cyclocarya paliurus. Changes ... Cyclocarya paliurus is only propagated from seeds which have pronounced dormancy. Overcoming seed dormancy is an important component of efficient and cost-effective seedling production of Cyclocarya paliurus. Changes in biochemical composition and enzyme activity were investigated during dormancy release. The activities of all the studied enzymes in the stratified seeds increased significantly, compared to those in the control samples. Of the enzymes examined, the activities of protease increased the most (413.8%), followed by peroxidase (278.7%), lipase (161.0%), glucose-6-phosphate dehydrognase (149.1%) and amylase (60.6%) after 8 months of stratification. Crude fat and protein constituted the bulk of the storage reserves in mature seeds of C. pal# urus. Compared with the seeds before stratification, about 45% of the starch, 46% of the protein and 11% of the crude fat were depleted during dormancy release of C. paliurus seeds, while the soluble sugar content was enhanced by 101.5% in the germinating seeds. Correlation analysis showed, during dormancy release of C. paliurus seeds, a close positive relationship between POD and G6PDH activity as well as soluble sugar content and amylase activity, while there was a significant negative relationship between storage substances and their related enzyme activities. 展开更多
关键词 Cyclocaryapaliurus enzyme activity seed dormancy soluble sugar storage substances STRATIFICATION
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Modifi cation of wheat bran insoluble and soluble dietary fibers with snail enzyme 被引量:17
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作者 Xin Liu Keke Suo +7 位作者 Pei Wang Xue Li Limin Hao Jiaqing Zhu Juanjuan Yi Qiaozhen Kang Jinyong Huang Jike Lu 《Food Science and Human Wellness》 SCIE 2021年第3期356-361,共6页
Insoluble dietary fiber(IDF)and soluble dietary fiber(SDF)extracted from wheat bran were modifi ed by snail enzyme and their physicochemical properties(water retention capacity and oil retention capacity),functional p... Insoluble dietary fiber(IDF)and soluble dietary fiber(SDF)extracted from wheat bran were modifi ed by snail enzyme and their physicochemical properties(water retention capacity and oil retention capacity),functional properties(cholesterol adsorption capacity,glucose adsorption capacity and antioxidant activity)and structural characterizations were evaluated.The results showed that snail enzyme modification led to the significant increase in oil retention capacity of IDF,glucose adsorption capacity and cholesterol adsorption capacity of IDF and SDF.Enzymatic modification also markedly improved the DPPH radical scavenging capacity and reducing power of IDF and SDF.Meanwhile,scanning electron microscopy(SEM)analysis indicated the microstructures of IDF and SDF powders were signifi cantly changed.Fourier transfer-infrared spectrometry(FT-IR)showed that snail enzyme modifi cation could degrade the part of cellulose and hemicellulose of IDF and SDF.All these improved physicochemical and functional properties of IDF and SDF might depend on their structural changes.It suggested that snail enzyme modifi cation could effectively improve physicochemical and functional properties of IDF and SDF from wheat bran. 展开更多
关键词 Snail enzyme Insoluble dietary fiber Soluble dietary fiber Physicochemical properties Functional properties
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The effects of vegetation restoration strategies and seasons on soil enzyme activities in the Karst landscapes of Yunnan, southwest China 被引量:7
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作者 Zhouzhou Fan Shuyu Lu +4 位作者 Shuang Liu Zhaorong Li Jiaxin Hong Jinxing Zhou Xiawei Peng 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1949-1957,共9页
Soil enzymes play a vital role in biogeochemical cycling and ecosystem functions.In this study,we examined the response of six soil enzymes to changes in physicochemical properties resulting from changes in season and... Soil enzymes play a vital role in biogeochemical cycling and ecosystem functions.In this study,we examined the response of six soil enzymes to changes in physicochemical properties resulting from changes in season and vegetation and geological conditions.Catalase,urease,acid phosphatase,invertase,amylase,and cellulase not only promote carbon,nitrogen,and phosphorus cycling,but also participate in the decomposition of harmful substances.Thirty-six soil samples were collected from karst and non-karst areas in two different seasons and from three different types of vegetation in Yunnan province,southwest China.Both vegetation types and season had significant effects on soil physicochemical properties and enzyme activities.In the same plot,soil water content,electrical conductivity,organic carbon,total nitrogen,and total phosphorus increased in the rainy season,indicating enhanced microbial metabolic activity.With the exception of urease activity,the remaining five enzymes showed higher activity in the rainy season.Changes in activities between the two seasons were significant in all samples.In the same season,activity levels of soil enzymes were higher in karst areas than in non-karst areas,and higher in natural forest than in artificial forests.The transformative abilities of soil elements are higher in karst areas than in non-karst areas,and higher in natural forests than in artificial forests.Correlation analysis showed that the activities of the six enzymes correlated significantly;however,soil physical and chemical indices,such as organic matter,pH,and moisture,which are essential for enzyme activity,differed by season.Redundancy analysis also revealed that the main factors influencing enzyme activity differed between the two seasons.The results from this study provide a theoretical basis for further research on the restoration of natural ecological systems in karst landscapes. 展开更多
关键词 KARST Soil enzymes Vegetation SEASON Natural forest
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Protective enzyme activity and physiological properties of four mulberry varieties affected by drought stress in the Panxi Region of Sichuan Province, China 被引量:6
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作者 RENYing-hong 《Forestry Studies in China》 CAS 2009年第3期190-195,共6页
In order to identify the effects of drought stress on protective enzyme activity and physiological properties, four mulberry varieties, i.e.,'Nanye- 1', 'Yunsang- 1', 'Xinyizhilai' and 'Husang-32' in the Panxi... In order to identify the effects of drought stress on protective enzyme activity and physiological properties, four mulberry varieties, i.e.,'Nanye- 1', 'Yunsang- 1', 'Xinyizhilai' and 'Husang-32' in the Panxi Region of Sichuan Province, China, were selected. The activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in four mulberry varieties was determined. Soluble protein, soluble sugar, proline, net photosynthetic rate and transpiration rate of mulberry leaves were analyzed. The results show that during the early stages of drought stress, protective enzyme activities in four mulberry varieties continually increased. However, prolonged and intensified drought stress decreased their activities. After re-watering, they gradually returned to normal levels. Under drought stress and after re-watering, 'Nanye-l' and 'Yunsang-l' clearly showed smaller changes in soluble protein content than the 'Xinyizhilai' and 'Husang-32' varieties, whereas changes in their soluble sugar content were clearly greater than these last two varieties. When water deficit was protracted and intensified, 'Nanye-1' and 'Yunsang-1' still showed higher net photosynthetic, transpiration rates and water-use efficiency than 'Xinyizhilai' and 'Husang-32'. 展开更多
关键词 drought stress mulberry varieties protective enzyme activity leaf quality PHYSIOLOGY
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Effects of angiotensin-converting enzyme inhibitor and angiotensin Ⅱ receptor blocker on one-year outcomes of patients with atrial fibrillation: insights from a multicenter registry study in China 被引量:4
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作者 Si-Qi LYU Yan-Min YANG +5 位作者 Jun ZHU Juan WANG Shuang WU Jia-Meng REN Han ZHANG Xing-Hui SHAO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第12期750-758,共9页
Objective To evaluate the effect of angiotensin-converting enzyme inhibitor(ACEI)/angiotensin Ⅱ receptor blocker(ARB)therapy on the prognosis of patients with atrial fibrillation(AF).Methods A total of 1,991 AF patie... Objective To evaluate the effect of angiotensin-converting enzyme inhibitor(ACEI)/angiotensin Ⅱ receptor blocker(ARB)therapy on the prognosis of patients with atrial fibrillation(AF).Methods A total of 1,991 AF patients from the AF registry were divided into two groups according to whether they were treated with ACEI/ARB at recruitment.Baseline characteristics were carefully collected and analyzed.Logistic regression was utilized to identify the predictors of ACEI/ARB therapy.The primary endpoint was all-cause mortality,while the secondary endpoints included cardiovascular mortality,stroke and major adverse events(MAEs)during the one-year follow-up period.Univariable and multivariable Cox regression were performed to identify the association between ACEI/ARB therapy and the one-year outcomes.Results In total,759 AF patients(38.1%)were treated with ACEI/ARB.Compared with AF patients without ACEI/ARB therapy,patients treated with ACEI/ARB tended to be older and had a higher rate of permanent AF,hypertension,diabetes mellitus,heart failure(HF),left ventricular ejection fraction(LVEF)<40%,coronary artery disease(CAD),prior myocardial infarction(MI),left ventricular hypertrophy,tobacco use and concomitant medications(all P<0.05).Hypertension,HF,LVEF<40%,CAD,prior MI and tobacco use were determined to be predictors of ACEI/ARB treatment.Multivariable analysis showed that ACEI/ARB therapy was associated with a significantly lower risk of one-year all-cause mortality[hazard ratio(HR)(95%CI):0.682(0.527-0.882),P=0.003],cardiovascular mortality[HR(95%CI):0.713(0.514-0.988),P=0.042]and MAEs[HR(95%CI):0.698(0.568-0.859),P=0.001].The association between ACEI/ARB therapy and reduced mortality was consistent in the subgroup analysis.Conclusions In patients with AF,ACEI/ARB was related to significantly reduced one-year all-cause mortality,cardiovascular mortality and MAEs despite the high burden of cardiovascular comorbidities. 展开更多
关键词 Angiotensin-converting enzyme inhibitor Angiotensin II receptor blocker Atrial fibrillation MORTALITY
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Angiotensin I converting enzyme(ACE)inhibitory activity and antihypertensive effects of rice peptides 被引量:5
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作者 Jingjing Dong Shen Wang +3 位作者 Xiaoyao Yin Min Fang Zhiyong Gong Yongning Wu 《Food Science and Human Wellness》 SCIE 2022年第6期1539-1543,共5页
In this paper,the antihypertension effect of rice peptide(RP)was studied.With spontaneously hypertensive rats(SHR)and Wistar Kyoto(WKY)as the research objects,RP disposable gastric and long-term gastric irrigation exp... In this paper,the antihypertension effect of rice peptide(RP)was studied.With spontaneously hypertensive rats(SHR)and Wistar Kyoto(WKY)as the research objects,RP disposable gastric and long-term gastric irrigation experiments were carried out and systolic blood pressure(SBP)was measured.At the end of the long-term gastric irrigation experiment,the content of nitric oxide(NO),angiotensin-converting enzyme(ACE),angiotensin II(Ang II)and renin in the plasma and the activity of ACE were determined.The results showed that RP could reduce systolic pressure of SHR and had time-dose dependence while high-dose RP signifi cantly reduced systolic pressure by 24.6 and 17.2 mm Hg,respectively after a single and long-term gastric irrigation test.RP also could inhibit the activity of ACE and increase the release of NO.These results suggested that the decompression mechanism of RP is likely to be related to the regulation of the renin-angiotensin system(RAS)and NO. 展开更多
关键词 Rice peptide Angiotensin-converting enzyme(ACE) Antihypertensive effect
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Metabolic enzyme inhibitory abilities, in vivo hypoglycemic ability of palmleaf raspberry fruits extracts and identification of hypoglycemic compounds 被引量:3
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作者 Jun Tan Danshu Wang +4 位作者 Yu Lu Yehan Wang Zongcai Tu Tao Yuan Lu Zhang 《Food Science and Human Wellness》 SCIE CSCD 2023年第4期1232-1240,共9页
The unripe palmleaf raspberry,namely Fupenzi(FPZ),is an important medicinal and edible food.This study aims to evaluate the potential of FPZ extracts prepared with different approaches in attenuating hyperglycemia,gou... The unripe palmleaf raspberry,namely Fupenzi(FPZ),is an important medicinal and edible food.This study aims to evaluate the potential of FPZ extracts prepared with different approaches in attenuating hyperglycemia,gout,Alzheimer’s disease,and pigmentation,to obtain the enriching fraction and to identify the major active compounds.Results indicated that FPZ extracts showed weak activity against acetylcholinesterase,considerable ability against tyrosinase and xanthine oxidase,but excellent inhibition onα-glucosidase.Ultrasound-assisted 40%ethanol extract(40EUS)gave the highest phenolics content,and the bestα-glucosidase inhibition(IC_(50)=0.08μg/mL),which is 877-fold higher than that of positive control acarbose.The 40%ethanol eluting fraction of 40EUS showed the strongestα-glucosidase inhibition with the IC_(50) value of 37.79 ng/mL,it could also effectively attenuate the fasting blood glucose level and oral glucose tolerance of C57BL/6 mice.Twenty-six compounds were identified from 40%ethanol fraction by using HPLC-QTOF-MS/MS,hydrolysable tannins(including 11 ellagitannins and 4 gallotannins)were the major compounds,phenolic acids came to the second.Above results could provide important technical supporting for the further application and research of FPZ in health foods and drugs against diabetes. 展开更多
关键词 Pal mleaf raspberry Extraction and identification enzyme inhibition HPLC-QTOF-MS/MS Hypoglycemic activity
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Effects of cold-hardening on compatible solutes and antioxidant enzyme activities related to freezing tolerance in Ammopiptanthus mongolicus seedlings 被引量:3
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作者 WANG Wei-juan CHEN Yu-zhen LIU Mei-qin LU Cun-fu 《Forestry Studies in China》 CAS 2008年第2期101-106,共6页
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
关键词 Ammopiptanthus mongolicus cold acclimation freezing tolerance compatible solute antioxidant enzyme
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