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The Mediation of Defense Responses of Ginseng Cells to an Elicitor from Cell Walls of Colletotrichum lagerarium by Plasma Membrane NAD(P)H Oxidases 被引量:2
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作者 胡向阳 Steven J.NEILL +2 位作者 方建颖 蔡伟明 汤章城 《Acta Botanica Sinica》 CSCD 2003年第1期32-39,共8页
NAD(P)H oxidases were detected in suspension cultured cells of ginseng (Panax ginseng C. A. Meyer). The activities of these enzymes were induced by an elicitor (Cle) extracted from cell walls of Col-letotrichum lagera... NAD(P)H oxidases were detected in suspension cultured cells of ginseng (Panax ginseng C. A. Meyer). The activities of these enzymes were induced by an elicitor (Cle) extracted from cell walls of Col-letotrichum lagerarium. In addition, Cle induced an oxidative burst and enhanced the synthesis of saponin, activity of phenylalanine ammonialyase (PAL) , accumulation of chalcone synthase (CHS) and the transcription of a hydroxyproline-rich glycoprotein gene ( hrgp ) . Pre-treatments with DPI and quinacrine (two inhibitors of mammalian neutrophil plasma membrane NADPH oxidase) for 30 min prior to Cle addition blocked the NAD(P)H oxidase activity induced by Cle. These inhibitors also inhibited the release of H2C2, the synthesis of saponin, PAL activity and CHS accumulation. Our data revealed homology between plasma membrane NAD(P)H oxidases of mammalian neutrophil cells and ginseng suspension cells. They also indicated that deactivated NAD(P)H oxidases catalysed the release of H2O2 and that H2O2 was functioning as a second messenger stimulating PAL activity, saponin synthesis and hrgp transcription. Elevations of Ca2 + and protein phos-phorylation/dephosphorylation were required for this defense process. We propose that NAD(P)H oxidases mediate the processes of Cle-induced defense responses in ginseng suspensions, and postulate the existence of a signalling cascade including extracellular Cle stimulation, activation of plasma membrane NAD(P)H oxidases, release of H2O2, and the intracellular responses of metabolism and gene transcription in ginseng suspension cells. 展开更多
关键词 NAD(P)H oxidase Panax ginseng Colletotrichum lagerarium ELICITOR signal transduction
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Potential of plant polyphenol oxidases in the decolorization and removal of textile and non-textile dyes 被引量:4
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作者 AMJAD ALI Khan QAYYUM Husain 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第4期396-402,共7页
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries.... In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation. 展开更多
关键词 DECOLORIZATION textile dyes polyphenol oxidases POTATO BRINJAL wastewater treatment removal of dyes
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Changes in the gut microbiota mediate the differential regulatory effects of two glucose oxidases produced by Aspergillus niger and Penicillium amagasakiense on the meat quality and growth performance of broilers 被引量:9
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作者 Shengru Wu Xiaodong Chen +3 位作者 Taohuan Li Hao Ren Lixin Zheng Xiaojun Yang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2020年第4期1232-1244,共13页
Background: Glucose oxidase(GOD), an aerobic dehydrogenase, has been used as an antibiotic substitute in feed.A study was conducted to evaluate the differential effects of 2 different GODs fermented by Aspergillus nig... Background: Glucose oxidase(GOD), an aerobic dehydrogenase, has been used as an antibiotic substitute in feed.A study was conducted to evaluate the differential effects of 2 different GODs fermented by Aspergillus niger or Penicillium amagasakiense on caecal microbiota and to further illuminate the potential roles of changes in the gut microbiota in regulating the growth performance and meat quality of broiler chickens.Results: A total of 420 one-day-old healthy Arbor Acres broilers were randomly assigned to 4 treatments: the control group,the antibiotic growth promoter(AGP) supplementation group, and the GOD-A and GOD-P(GODs produced by A. niger and P. amagasakiense, respectively) groups. As a result, supplementation with GOD produced by P. amagasakiense could significantly improve the average daily weight gain and average daily feed intake of broilers before 21 days of age by significantly increasing the enzymatic activities of jejunal amylase and those of ileal amylase, chymotrypsin, and lipase in21-day-old broilers and could increase the enzymatic activities of duodenal amylase, jejunal amylase and lipase, and ileal chymotrypsin and lipase in 42-day-old broilers. Meanwhile, compared with AGP treatment, supplementation with GOD produced by P. amagasakiense significantly decreased the L value of 21-day-old broilers and the Δp H and L* value of 42-day-old broilers, while supplementation with GOD produced by A. niger significantly increased the p H24 hvalue of 21-day-old and 42-day-old broilers by reducing plasma malondialdehyde content. By using 16 S r RNA sequencing, we found that the beneficial bacteria and microbiota in broilers were not disturbed but were improved by GOD supplementation compared with ADP treatment, including the genera Eubacterium and Christensenel a and the species uncultured_Eubacterium_sp,Clostridium_asparagiforme, and uncultured_Christensenel a_sp, which were positively related to the improved intestinal digestive enzymatic activities, growth performance, and meat quality of broilers.Conclusion: The altered gut microbiota induced by supplementation with glucose oxidase produced by P. amagasakiense mediate better regulatory effects on the meat quality and growth performance of broilers than that induced by supplementation with glucose oxidase produced by A. niger. 展开更多
关键词 BROILER Glucose oxidase Growth performance Gut function Gut microbiota
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Status and Advances of Researches on GA 20-oxidases 被引量:2
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作者 Li Wei Chen Xiaoyang Li Hui Guo HaiCollege of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, P. R. China 《Forestry Studies in China》 CAS 2003年第1期49-54,共6页
GA 20-oxidase, the most important limiting enzyme, can catalyze a series of oxidization of GA biosynthesis pathway from GA12 to GA9 and from GA53 to GA20 in the higher plants. This paper reviews the studies on the cha... GA 20-oxidase, the most important limiting enzyme, can catalyze a series of oxidization of GA biosynthesis pathway from GA12 to GA9 and from GA53 to GA20 in the higher plants. This paper reviews the studies on the characters of GA 20-oxidase, the gene and the protein of GA 20-oxidase and the regulation of GA 20-oxidase gene expression in recent years. At the same time, the prospects for the gene transformation of GA 20-oxidase in agriculture, forestry and horticulture are also discussed. 展开更多
关键词 higher plants GA 20-oxidase gene transformation
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DNA methylation of the Monoamine Oxidases A and B genes in postmortem brains of subjects with schizophrenia
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作者 Qiaohui Yang Keiko Ikemoto +5 位作者 Satoshi Nishino Junko Yamaki Yasuto Kunii Akira Wada Yoshimi Homma Shin-Ichi Niwa 《Open Journal of Psychiatry》 2012年第4期374-383,共10页
Aims: We focused on DNA methylation of the promoter regions of the Monoamine Oxidase (MAO) A and B genes from postmortem brains of subjects with schizophrenia. Methods: We determined levels of DNA methylation using ge... Aims: We focused on DNA methylation of the promoter regions of the Monoamine Oxidase (MAO) A and B genes from postmortem brains of subjects with schizophrenia. Methods: We determined levels of DNA methylation using genomic DNA samples purified from four brain areas: prefrontal cortex (PFC), hippocampus, occipital cortex and nucleus accumbens (NAc), by a bisulfite sequencing method from seven normal subjects and six subjects with schizophrenia. Results: Although very few methylated CpGs of the MAOA and MAOB genes were detected in male samples, various DNA methylation patterns were present in female samples, and some differences were found in such patterns between normal subjects and subjects with schizophrenia. In the PFC, the average level of methylation of both genes was significantly higher in subjects with schizophrenia than in normal subjects. The content of highly methylated alleles of the MAOA gene in the NAc was significantly associated with schizophrenia, with similar results obtained for the MAOB gene in both the NAc and PFC. Some CpG sites showed higher levels of methylation in schizophrenia than in normal subjects. Conclusions: Levels of methylation were quite high in NAc and PFC in female subjects with schizophrenia compared with those in female normal subjects. 展开更多
关键词 DNA Methylation MONOAMINE oxidasE Nucleus ACCUMBENS POSTMORTEM Brain SCHIZOPHRENIA
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Age-Related Surface Oxidases Shed into Body Fluids as Targets to Prevent Skin Aging and Reduce Cardiovascular Risk
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作者 D. James Morré Dale Kern +2 位作者 Christiaan Meadows Helen Knaggs Dorothy M. Morré 《World Journal of Cardiovascular Diseases》 2014年第3期119-129,共11页
Age-related Ecto-Nicotinamide Adenine Dinucleotide Oxidase Disulfide Thiol Exchangers 3 (ENOX3) or age-related NADH oxidases (arNOX) are expressed at the cell surface as five members of the TM-9 superfamily, initially... Age-related Ecto-Nicotinamide Adenine Dinucleotide Oxidase Disulfide Thiol Exchangers 3 (ENOX3) or age-related NADH oxidases (arNOX) are expressed at the cell surface as five members of the TM-9 superfamily, initially membrane anchored, all functionally similar, with the N-termini exposed at the cell’s exterior. ECTO-NOXes are cell surface proteins with both time-keeping CoQH2 [NAD(P)H] oxidase and protein disulfidethiol interchange activities. They are designated as ECTO-NOX proteins because of their localization on the outer surface of the plasma membrane and to distinguish them from the phox-NOXes of host defense. A ca. 30 kDa N-terminal fragment is cleaved and accumulates in body fluids (serum, saliva, urine, perspiration). arNOXes appear around age 30 and increase steadily thereafter. Reduced quinones, i.e., reduced coenzyme Q, of the plasma membrane are natural substrates. NAD(P)H is oxidized as an artificial substrate. In one phase of the arNOX cycle electrons are transferred to oxygen to generate superoxide. Substrates for the shed forms of arNOX appear to be proteins of body fluids. Circulating lipoproteins and skin matrix proteins emerge as potentially important health-related targets. Through oxidation of collagen, elastin and other proteins of the skin matrix, arNOXes are major contributors to skin aging through tyrosine and thiol oxidation and subsequent cross linking. The main destructive action of arNOX, however, may be to directly oxidize circulating lipoproteins. arNOX in the blood is structured as an integral component of the LDL particle through site-specific binding. As such, arNOXes are implicated as major risk factors for cardiovascular disease due to specific oxidation of LDLs. The superoxide produced and its conversion to hydrogen peroxide would be one part of the potentially destructive properties by contribution to lipid oxidation. Inhibition of arNOX proteins provides a rational basis for anti-aging interventions and their elimination as a major risk factor of atherogenesis. 展开更多
关键词 Atherosclerosis Cardiovascular Risk AGE-RELATED NADH oxidase (arNOX) TM9 SUPERFAMILY of TRANSMEMBRANE Proteins Serum and Body Fluids SALIVA Skin Aging Low Density LIPOPROTEINS
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Gnetum montanum extract ameliorates ethanol-induced hepatic injury and metabolic dysfunction via inhibition of xanthine oxidase
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作者 Hong-Linh Tran Thuy-Duong Nguyen +2 位作者 Thu-Hang Nguyen Hai-Nam Nguyen Duc-Vinh Pham 《Asian Pacific Journal of Tropical Biomedicine》 2025年第3期98-108,共11页
Objective:To investigate the effects of a crude extract from Gnetum montanum Markgr.on ethanol-induced hepatotoxicity and metabolic disorders.Methods:Alcoholic liver disorder was induced in mice by administering incre... Objective:To investigate the effects of a crude extract from Gnetum montanum Markgr.on ethanol-induced hepatotoxicity and metabolic disorders.Methods:Alcoholic liver disorder was induced in mice by administering increasing doses of ethanol via oral gavage.Biomarkers of liver injury and oxidative stress were assessed at the end of the study.Liver tissue damage and fat deposition were evaluated using hematoxylin and eosin and oil red O staining,respectively.In addition,key biomarkers were examined in acetaldehyde-treated HepG2 cells.Results:Ethanol consumption induced characteristic pathological changes,including elevated serum markers of liver injury,hepatic lipid accumulation,and oxidative stress in liver tissues.Oral administration of Gnetum montanum extract(175 and 350 mg/kg)decreased serum aspartate aminotransferase,alanine aminotransferase,γ-glutamyl transferase,and bilirubin levels in ethanol-treated mice.The extract also lowered triglyceride levels in serum and liver tissue in a dose-dependent manner.Furthermore,it mitigated malondialdehyde levels,preserved reduced glutathione levels,and enhanced catalase activity and total antioxidant capacity in liver tissue homogenates.Additionally,ethanol-induced hyperuricemia was suppressed by Gnetum montanum extract by inhibiting xanthine oxidase activity.Similar effects were observed in Gnetum montanum extract-treated HepG2 cells.Conclusions:This study demonstrates that Gnetum montanum extract alleviates ethanol-induced hepatic injury by alleviating oxidative stress and inhibiting xanthine oxidase activity. 展开更多
关键词 Alcoholic liver disease Gnetum montanum Hepatic steatosis Hepatoprotective effect Xanthine oxidase
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Natural variations in a barley aldehyde oxidase 1 gene affect seed germination and malting quality
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作者 Le Xu Peng Wang +5 位作者 Xiaoqi Zhang Qisen Zhang Penghao Wang Yanhao Xu Chengdao Li Wenying Zhang 《The Crop Journal》 2025年第1期299-303,共5页
Multiple phytohormones,including gibberellin(GA),abscisic acid(ABA),and indole-3-acetic acid(IAA),regulate seed germination.In this study,a barley aldehyde oxidase 1(HvAO1)gene was identified,which is located near the... Multiple phytohormones,including gibberellin(GA),abscisic acid(ABA),and indole-3-acetic acid(IAA),regulate seed germination.In this study,a barley aldehyde oxidase 1(HvAO1)gene was identified,which is located near the SD2(seed dormancy 2)region at the telomeric end of chromosome 5H.A doubledhaploid population(AC Metcalfe/Baudin)was used to characterize HvAO1 and validated its association with seed germination and malting quality.Aldehyde oxidase is predicted to catalyse the oxidation of various aldehydes,such as indoleacetaldehyde and abscisic aldehyde,into IAA and ABA,which is the final step of IAA/ABA biogenesis.This process influences the final IAA/ABA concentration in the seed,affecting the seed dormancy.Sequence analysis revealed substantial variations in the HvAO1 promoter regions between AC Metcalfe and Baudin.The combining seed germination tests,genetic variation analysis,gene expression,and phytohormone measurements showed that Baudin,which displays strong seed dormancy,has a specific sequence variation in the promoter region of the HvAO1 gene.This variation is associated with a higher expression level of the HvAO1 gene and an increased level of ABA than those in AC Metcalfe,which shows weak dormancy and lacks this sequence variation.In addition to its strong effect on the SD2 gene,HvAO1 shows excellent potential to fine-tune malting quality and seed dormancy,as evidenced by genotyping with HvAO1-specific markers,dormancy phenotypes,and malting quality.Our findings provide a new strategy for introducing favourable HvAO1 alleles to achieve the desired level of seed dormancy and high malting quality in barley. 展开更多
关键词 Barley(Hordeum vulgare L.) DORMANCY GERMINATION Malting quality Aldehyde oxidase
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Single-atom rhodium mimicking the oxidase and peroxidase for NADH cascade oxidation
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作者 Hong-Jin Xue Meng Zhang +6 位作者 Yong-Qing Li Chao-Ran Liu Xin-Yu Ma Qin-Bin He Yin-Chuan Wang Jin-Xing Chen Jian-Feng Qiu 《Rare Metals》 2025年第6期4025-4037,共13页
Constructing high-performance nanozymes for specific biomolecules is crucial but challenging for practical applications and fundamental research.Herein,through the examination of the catalytic reaction paths of natura... Constructing high-performance nanozymes for specific biomolecules is crucial but challenging for practical applications and fundamental research.Herein,through the examination of the catalytic reaction paths of natural nicotinamide adenine dinucleotide(NADH)oxidase(NOX),a novel and efficient single-atom rhodium catalyst(Rh1/NC)was developed to mimic NOX.The Rh_(1)/NC demonstrated the ability to catalyze the dehydrogenation of NADH and transfer electrons to O_(2)to generate H_(2)O_(2)through the typical two-electron pathway.Furthermore,our findings revealed that Rh_(1)/NC exhibits the ability to catalyze the conversion of produced H_(2)O_(2)into OH under mildly acidic conditions.This process amplifies the oxidation of NADH,showcasing NADH peroxidase-like activity(NPx-like).As a paradigm,this unique dual enzyme-like property of Rh_(1)/NC with a positive feedback effect holds significance in disrupting cancer cellular homeostasis.Rh_(1)/NC can effectively consume NADH via cascade biocatalytic reactions within cancer cells,further triggering the elevation of reactive oxygen species(ROS),leading to impaired oxidative phosphorylation and decreased mitochondrial membrane potential,thus damaging the adenosine triphosphate(ATP)synthesis.The resulting'domino effect'interferes with the energy metabolism homeostasis of cancer cells,ultimately promoting cell apoptosis.This study provides potential guidance for the rational design of materials with greater capabilities. 展开更多
关键词 NADH oxidase mimetics Single-atom nanozymes Cascade biocatalytic reactions Positive feedback Cell apoptosis
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Diamine oxidase as a biomarker for depression and disease activity in inflammatory bowel disease:A cross-sectional observational study
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作者 Su-Cong Lyu Guo-Qiang Zhong +4 位作者 Run-Jie Shi Yan Sun Jin Li Ming-Song Li Ye Chen 《World Journal of Psychiatry》 2025年第8期320-331,共12页
BACKGROUND Diamine oxidase(DAO)is secreted by epithelial cells in the intestinal villi,and its serum levels are elevated after intestinal mucosal damage.d-lactate(D-LA)is a gut microbial metabolite that can enter the ... BACKGROUND Diamine oxidase(DAO)is secreted by epithelial cells in the intestinal villi,and its serum levels are elevated after intestinal mucosal damage.d-lactate(D-LA)is a gut microbial metabolite that can enter the systemic circulation if intestinal barrier function is impaired.Both DAO and D-LA are serum markers of small bowel mucosal integrity,and can be valuable biomarkers of intestinal barrier damage in inflammatory bowel disease(IBD).Intestinal barrier dysfunction was recently found to contribute to psychological symptoms in IBD patients.However,the correlations among DAO,D-LA,psychological symptoms,and disease activity in IBD remain unexplored.AIM To explore the correlations between serum markers of intestinal barrier dysfunction and psychological symptoms in IBD.METHODS We enrolled of 126 participants in this study.Psychological symptom questionnaires(depression,patient health questionnaire-9;anxiety,generalized anxiety disorder-7;and stress,perceived stress scale)and a quality of life(QOL)questionnaire(IBD questionnaire 32)were collected at the baseline.Serum DAO and D-LA levels were measured to assess intestinal barrier integrity.Receiver operating characteristic(ROC)curves were used to identify candidate markers of psychological symptoms and disease activity in IBD patients.Logistic regression was applied,with DAO as an independent variable for predicting psychological symptoms in IBD.RESULTS Serum DAO levels were significantly higher in IBD patients with moderate-to-severe psychological symptoms than in patients with mild or no psychological symptoms.DAO was positively correlated with depression and negatively correlated with QOL in IBD patients.ROC curves revealed that DAO was independently associated with psychological symptoms and clinical activity in patients with IBD.Additionally,logistic regression analysis revealed that each 1-ng/mL increase in DAO levels was significantly associated with an increased risk of psychological symptoms in IBD patients(OR:1.019,95%CI:1.002-1.037).These results highlight the potential of DAO as a novel biomarker for both depression and disease activity in IBD patients.CONCLUSION This study indicates that DAO may be associated with depression and disease activity in IBD patients;however,prospective studies are required to validate its causal relationship. 展开更多
关键词 Diamine oxidase DEPRESSION Intestinal barrier dysfunction Disease activity Inflammatory bowel disease Quality of life
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Maize plastid terminal oxidase(ZmPTOX)regulates the color formation of leaf and kernel by modulating plastid development
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作者 Qiang Huang Zhuofan Zhao +11 位作者 Xiaowei Liu Xin Yuan Ruiqing Zhao Qunkai Niu Chuan Li Yusheng Liu Danfeng Wang Tao Yu Hongyang Yi Chengming Yang Tingzhao Rong Moju Cao 《Journal of Genetics and Genomics》 2025年第3期441-445,共5页
Carotenoids are the largest group of natural pigments responsible for the yellow,orange,and red colors in plant kernels,fruits,and leaves(Gupta and Hirschberg,2021).In plants,carotenoids are involved in manybiological... Carotenoids are the largest group of natural pigments responsible for the yellow,orange,and red colors in plant kernels,fruits,and leaves(Gupta and Hirschberg,2021).In plants,carotenoids are involved in manybiological processes,such as acting as accessory light-harvesting pigments in photosynthesis,participating in photoprotection,and serving as precursors for the hormones abscisic acid(ABA)and strigolactones(Ruiz-Sola and Rodriguez-Concepcion,2012). 展开更多
关键词 leaf color kernel color PHOTOPROTECTION photosynthesis maize plastid terminal oxidase plastid development zmptox abscisic acid aba
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磷酸银/多孔羟基锡酸锌的制备及其在分光光度法测定抗坏血酸中的应用
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作者 何琴 刘国栋 +1 位作者 程前 黄保军 《中国无机分析化学》 北大核心 2026年第1期136-145,共10页
抗坏血酸(AA)的快速、准确检测在疾病预防、食品质量控制和药品安全监测等领域具有重要意义。采用沉淀法制备ZnSn(OH)_(6),并通过强碱刻蚀技术在其表面构建多孔结构,以增强比表面积和活性位点暴露。随后,通过沉淀法在多孔ZnSn(OH)_(6)... 抗坏血酸(AA)的快速、准确检测在疾病预防、食品质量控制和药品安全监测等领域具有重要意义。采用沉淀法制备ZnSn(OH)_(6),并通过强碱刻蚀技术在其表面构建多孔结构,以增强比表面积和活性位点暴露。随后,通过沉淀法在多孔ZnSn(OH)_(6)表面负载Ag_(3)PO_(4),成功制备了磷酸银/羟基锡酸锌[Ag_(3)PO_(4)/ZnSn(OH)_(6)-2]复合材料,有效解决了磷酸银易团聚的问题。作为对照,在未刻蚀的ZnSn(OH)_(6)表面负载Ag_(3)PO_(4)制备了Ag_(3)PO_(4)/ZnSn(OH)_(6)-1。研究表明,两种复合材料均表现出显著的类氧化酶活性,能够在常温常压下催化水中的溶解氧(O2)氧化3,3',5,5'-四甲基联苯胺(TMB)生成蓝色的氧化型产物(Ox-TMB),Ag_(3)PO_(4)/ZnSn(OH)_(6)-2催化底物的最大反应速率较Ag_(3)PO_(4)/ZnSn(OH)_(6)-1提升2.75倍。AA的加入对体系的显色有明显的抑制作用,且抑制程度与AA浓度呈良好的线性关系。基于此,构建了一种简单、快速、高灵敏度的AA检测方法。优化后的反应条件为:温度25℃、pH=5.60、催化剂(5 mg/mL)用量125μL、TMB(20 mmol/L)用量20μL。结果表明,该方法在0~45.6μmol/L范围内呈现优异线性(ΔA=28823.2c-0.00841,R^(2)=0.9956),检出限低至0.108μmol/L(S/N=3),5倍浓度的亚硝酸钠、醋酸锌、L-脯氨酸等不干扰AA的测定。应用于维生素C片剂分析时,加标回收率达98.5%~104%,显著优于同类文献报道的分光光度法。本研究不仅为AA检测提供了新型纳米酶传感平台,也为多孔载体设计优化纳米酶活性提供了理论参考。 展开更多
关键词 磷酸银/羟基锡酸锌 类氧化酶 分光光度法 抗坏血酸
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超声心动图结合生物标志物对脓毒症心肌损伤的诊断与预后评估价值
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作者 贺丹娜 赵瑞平 +3 位作者 李帷 胡君 杨杨 宋秀荣 《中国心血管病研究》 2026年第2期133-139,共7页
目的探讨超声心动图联合血清烟酰胺腺嘌呤二核苷酸磷酸氧化酶(NOX2)、分泌型卷曲相关蛋白5(SFRP5)对脓毒症心肌损伤的诊断及预后评估的临床价值。方法选取2020年2月至2023年5月包头市中心医院收治的400例脓毒症患者作为研究对象,根据是... 目的探讨超声心动图联合血清烟酰胺腺嘌呤二核苷酸磷酸氧化酶(NOX2)、分泌型卷曲相关蛋白5(SFRP5)对脓毒症心肌损伤的诊断及预后评估的临床价值。方法选取2020年2月至2023年5月包头市中心医院收治的400例脓毒症患者作为研究对象,根据是否并发心肌损伤分为损伤组(173例)和非损伤组(227例),根据治疗28 d后的预后情况分为死亡组(65例)和存活组(108例)。采用ELISA法检测血清NOX2、SFRP5表达水平,Pearson法分析血清NOX2、SFRP5水平与超声心动图指标相关性,ROC曲线分析超声心电图指标与血清NOX2、SFRP5单独及联合对脓毒症患者心肌损伤的诊断及预后评估的价值,Lasso-Cox回归分析影响脓毒症心肌损伤患者死亡的相关因素。结果与非损伤组相比,损伤组LAD与血清NOX2[(145.39±22.85)pg/ml比(118.27±21.46)pg/ml]、C反应蛋白、降钙素原、心肌肌钙蛋白I、肌酸激酶同工酶水平升高,LVEF与血清SFRP5[(37.08±6.65)ng/ml比(45.15±7.93)ng/ml]水平降低(P<0.05)。血清NOX2水平与LVEF呈负相关,与LVEDD、LAD呈正相关。血清SFRP5水平与LVEF呈正相关,与LVEDD、LAD呈负相关(P<0.001)。LVEF、LVEDD、LAD与血清NOX2、SFRP5单独诊断脓毒症患者心肌损伤的AUC分别为0.894、0.908、0.752、0.862、0.874,联合诊断的AUC为0.987,联合诊断价值较高(P<0.001)。与存活组相比,死亡组LAD、LVEDD、APACHEⅡ评分与血清NOX2[(166.51±25.82)pg/ml比(132.68±21.06)pg/ml]、降钙素原、心肌肌钙蛋白I、肌酸激酶同工酶水平升高,LVEF与血清SFRP5[(30.67±5.32)ng/ml比(40.93±7.45)ng/ml]水平降低(P<0.05);Lasso-Cox回归分析结果显示,肌酸激酶同工酶、LVEDD、LAD、NOX2均为影响脓毒症心肌损伤患者死亡的危险因素,LVEF、SFRP5为保护因素(P<0.05);LVEF、LVEDD、LAD与血清NOX2、SFRP5单独预测脓毒症心肌损伤患者死亡的AUC分别为0.917、0.890、0.859、0.845、0.857,联合预测的AUC为0.984,联合预测价值较高(P<0.001)。结论脓毒症并发心肌损伤患者血清NOX2水平升高、SFRP5水平降低,超声心电图指标联合血清NOX2、SFRP5在脓毒症并发心肌损伤的诊断、预后评估中具有较高临床价值。 展开更多
关键词 心肌损伤 脓毒症 超声心动图 烟酰胺腺嘌呤二核苷酸磷酸氧化酶2 分泌型卷曲相关蛋白5
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烤烟新品系‘YM2020’中部叶的烘烤特性及烘烤工艺
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作者 李洪臣 杨军杰 +1 位作者 常剑波 夏宗良 《中国农学通报》 2026年第1期194-199,共6页
烤烟新品系‘YM2020’是‘云烟87’的自然突变体。为解决其沿用传统烘烤工艺时褐斑发生率高的问题,明确适宜烘烤参数,以‘云烟87’作为对照,通过暗箱模拟与动态烘烤试验,系统测定‘YM2020’中部叶的变黄/变褐特性、失水规律、叶绿素降... 烤烟新品系‘YM2020’是‘云烟87’的自然突变体。为解决其沿用传统烘烤工艺时褐斑发生率高的问题,明确适宜烘烤参数,以‘云烟87’作为对照,通过暗箱模拟与动态烘烤试验,系统测定‘YM2020’中部叶的变黄/变褐特性、失水规律、叶绿素降解动态、多酚氧化酶(PPO)活性及形态收缩率等关键指标,并构建配套烘烤工艺。结果表明,‘YM2020’与‘云烟87’的易烤性相当,变黄速度相近(72 h完全变黄);但‘YM2020’耐烤性中等[PPO活性均值0.3~0.4 U/(g·FW)],弱于‘云烟87’[PPO活性<0.3 U/(g·FW)]。烘烤过程中,‘YM2020’失水速率呈现“慢→快→慢”趋势,叶绿素降解速率滞后于‘云烟87’(0~48 h降解速率低12.6%),且收缩率(长度19.61%、宽度37.35%)显著高于对照。基于上述特性,提出分阶段温湿度协同调控工艺,即变黄阶段(37~43℃)梯度升温促进叶绿素降解,定色阶段(45~54℃)精准控温平衡物质转化与干燥速率,干筋阶段(54~62℃)分阶升温实现主脉全干。 展开更多
关键词 烤烟 含水量 失水规律 叶绿素降解率 多酚氧化酶 烘烤特性 烘烤工艺
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The Phylogenetic Relationships among Four Subspecies of the Genus Locusta Based on Sequences of Three Subunit of Cytochrome Oxidase 被引量:3
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作者 张道川 王健学 智永超 《Agricultural Science & Technology》 CAS 2011年第2期244-248,共5页
[Objective] The aim was to explore the phylogenetic relationships among four subspecies of the genus Locusta.[Method] The sequences of three subunits of cytochrome oxidase of Locusta migratoria tibetensis and Locusta ... [Objective] The aim was to explore the phylogenetic relationships among four subspecies of the genus Locusta.[Method] The sequences of three subunits of cytochrome oxidase of Locusta migratoria tibetensis and Locusta migratoria manilensis were amplified and sequenced(COⅠ 1 539 bp,COⅡ 684 bp,CO Ⅲ 792 bp,with the total of 3 015 bp).The corresponding sequenses of Locusta migratoria migratoria and Locusta migratoria migratorioides were obtained from GenBank and constructed a multiple alignment.Phylogenic trees of four subspecies of L.migratoria were constructed by Neighbor-Joining,Maximum-parsimony and Bayesian,respectively.[Result] The average content of A + T in three subunits of four subspecies was 69.57%;the third site of codon showed the highest A + T content,and the COⅠ had the highest A + T content(87.6%);The nucleotide substitution mainly occurred at the third site of codon,and the nucleotide replacement rate of CO Ⅱ was the highest.The second site of codon was conservative,so the replacement rate was in the range of 5.9%-15%.The start codon of COⅠ was CCG or ACG.Genetic distances among four subspecies were ranged from 0.001 to 0.076.The relationship between L.m.tibetensis and Locusta migratoria manilensis was the closest,followed by L.m.migratorioides and L.m.migratorioides,while the genetic distance between L.m.tibetensis and L.m.migratorioides was the largest.[Conclusion] The phylogenetic relationships among four subspecies of Locusta migratoria is L.m.tibetensis,L.m.manilensis,L.m.migratoria,L.m.migratorioides. 展开更多
关键词 LOCUSTA SUBSPECIES Phylogenetic relationship MITOCHONDRION Cytochrome oxidase
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高等植物赤霉素生物合成关键组分GA20-oxidase氧化酶基因的研究进展 被引量:17
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作者 吴建明 陈荣发 +2 位作者 黄杏 丘立杭 李杨瑞 《生物技术通报》 CAS CSCD 北大核心 2016年第7期1-12,共12页
GA-20氧化酶(GA-20 oxidase)是重要的GA生物合成和调控酶,直接催化生成有生物活性的GAs,是一种多功能酶,最显著的特点就是负反馈调节。GA20-氧化酶在植物发育和生理过程中起着重要的调控作用。综述了高等植物体内GA20氧化酶基因的克隆... GA-20氧化酶(GA-20 oxidase)是重要的GA生物合成和调控酶,直接催化生成有生物活性的GAs,是一种多功能酶,最显著的特点就是负反馈调节。GA20-氧化酶在植物发育和生理过程中起着重要的调控作用。综述了高等植物体内GA20氧化酶基因的克隆及表达调控研究及其对株高、纤维、开花、产量性状等影响,重点阐述了GA20氧化酶基因与激素、光周期、抗性等之间的相互作用,以便更好地揭示GA-20氧化酶信号网络系统及其作用机制。 展开更多
关键词 植物激素 赤霉素合成酶 GA-20氧化酶 基因
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30种海棠果的综合品质分析及其黄嘌呤氧化酶抑制活性的探究
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作者 刘瑜 葛红娟 +3 位作者 张鑫鑫 孙吉禄 马荣群 孟祥红 《食品工业科技》 北大核心 2026年第6期294-305,共12页
为更好地了解不同品种海棠果的品质特性,有效利用海棠果资源,本研究测定了30个品种海棠果的单果重、水分含量、可溶性固形物等理化指标及黄嘌呤氧化酶半抑制浓度等生物活性指标,通过测定DPPH自由基清除能力、ABTS+自由基清除能力和铁离... 为更好地了解不同品种海棠果的品质特性,有效利用海棠果资源,本研究测定了30个品种海棠果的单果重、水分含量、可溶性固形物等理化指标及黄嘌呤氧化酶半抑制浓度等生物活性指标,通过测定DPPH自由基清除能力、ABTS+自由基清除能力和铁离子还原能力比较了体外抗氧化活性,并对其进行了相关性分析、主成分分析和聚类分析。结果表明,所测品种海棠果中总酚含量(2.749~80.877 mg GAE/g DW)和总黄酮含量(3.522~167.312 mg RE/g DW)较高,其与果实横径、纵径、单果重呈显著负相关(P<0.05),具有较好的抗氧化活性和黄嘌呤氧化酶抑制活性。经主成分分析,5种主成分累计贡献率为82.570%,海棠果实综合评价模型筛选出‘2010-6’为品质最佳的品种,其总酚、总黄酮含量在所测品种中最高,且具有较好的抗氧化活性(0.827、0.654和0.518 mmol TE/g DW)和较强的黄嘌呤氧化酶抑制活性(IC_(50)=2.724 mg/mL),具有较好的开发利用的前景。海棠果的糖酸比(0.47~5.48)较小,更适宜用来加工制成果汁、果酒等产品,或作为提取活性物质的来源。本研究从营养品质、功能特性等方面对海棠果进行了全面的分析,为不同品种海棠果的开发利用提供理论依据。 展开更多
关键词 海棠果 品质特性 综合分析 黄嘌呤氧化酶
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山茱萸提取物对慢性肾功能衰竭大鼠的肾保护作用及对oxidase/ROS/ERK信号通路的影响 被引量:21
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作者 丁国明 戢晴 韩颖敏 《新中医》 CAS 2020年第18期14-18,共5页
目的:探讨山茱萸提取物对慢性肾功能衰竭(CRF)大鼠的肾保护作用及对氧化酶(oxidase)/活性氧(ROS)/细胞外信号调节激酶(ERK)信号通路的影响。方法:将40只雄性SD大鼠分为正常组、模型组、阳性药组和山茱萸组,每组10只。除正常组外,其余各... 目的:探讨山茱萸提取物对慢性肾功能衰竭(CRF)大鼠的肾保护作用及对氧化酶(oxidase)/活性氧(ROS)/细胞外信号调节激酶(ERK)信号通路的影响。方法:将40只雄性SD大鼠分为正常组、模型组、阳性药组和山茱萸组,每组10只。除正常组外,其余各组按0.25 g/(kg·d)的剂量灌胃腺嘌呤溶液,连续给予21 d制备CRF模型。模型制备成功后,阳性药组按0.75 g/(kg·d)的剂量给予黄葵胶囊,山茱萸组按0.60 g/(kg·d)的剂量给予山茱萸提取物,正常组和模型组给予等量生理盐水,持续28 d。对肾组织进行病理学检查及评分,同时检测肾功能指标、血清中肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)含量及肾脏中相关蛋白的含量。结果:正常组大鼠肾脏病理未观察到损伤迹象;模型组出现弥漫肾小球和肾小管萎缩、炎性细胞浸润和间质纤维化等病变;阳性药组肾小球和肾小管萎缩、炎性细胞浸润和间质纤维化等病变较模型组减轻;山茱萸组肾小球和肾小管萎缩、炎性细胞浸润和间质纤维化等病变程度介于模型组和阳性药组之间。与正常组比较,模型组炎症评分、纤维化评分及尿素氮(BUN)、肌酐(SCr)、尿蛋白(UP)、TNF-α、IL-6、α-平滑肌肌动蛋白(α-SMA)、NADPH氧化酶1(NOX1)、ROS、磷酸化ERK(p-ERK)含量均增加(P<0.05);与模型组比较,阳性药组和山茱萸组炎症评分、纤维化评分及BUN、SCr、UP、TNF-α、IL-6、α-SMA、NOX1、ROS、p-ERK含量均降低(P<0.05);与阳性药组比较,山茱萸组炎症评分、纤维化评分及BUN、SCr、UP、TNF-α、IL-6、α-SMA、NOX1、ROS、p-ERK含量均增加(P<0.05)。结论:山茱萸提取物可以通过抑制肾组织炎症反应和纤维化对CRF大鼠起到一定的保护作用,其机制可能与oxidase/ROS/ERK信号通路有关。 展开更多
关键词 慢性肾功能衰竭 山茱萸提取物 oxidase/ROS/ERK信号通路 动物实验 大鼠
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Activation of Plasma Membrane NADPH Oxidase and Generation of H_2O_2 Mediate the Induction of PAL Activity and Saponin Synthesis byEndogenous Elicitor in Suspension-Cultured Cells of Panax ginseng 被引量:1
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作者 胡向阳 Steven J NEILL +1 位作者 蔡伟明 汤章城 《Acta Botanica Sinica》 CSCD 2003年第12期1434-1441,共8页
Endogenous elicitor, termed cellulase-degraded cell wall (CDW), was prepared from the cell wall of suspension-cultured ginseng (Panax ginseng C.A. Meyer) cells via cellulase degradation. CDW activated the NADPH oxidas... Endogenous elicitor, termed cellulase-degraded cell wall (CDW), was prepared from the cell wall of suspension-cultured ginseng (Panax ginseng C.A. Meyer) cells via cellulase degradation. CDW activated the NADPH oxidase activity of isolated plasma membranes and stimulated in vivo H2O2 generation in ginseng cell suspensions. CDW also increased the activity of phenylalanine ammonia lyase (PAL), expression of a P. ginseng squalene epoxidase (sqe) gene and saponin synthesis. NADPH oxidase inhibitors inhibited both in vitro NADPH oxidase activity and in vivo H2O2 generation. Induction of PAL activity, saponin synthesis and sqe gene expression were all inhibited by such inhibitor treatments and reduced by incubation with catalase and HA scavengers. These data indicate that activation of NADPH oxidase and generation of H2O2 are essential signalling events mediating defence responses induced by the endogenous elicitor(s) present in CDW. 展开更多
关键词 plasma membrane NADPH oxidase H2O2 ELICITOR Panax ginseng
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赤霉素诱导甘蔗GA20-Oxidase基因实时荧光定量PCR分析 被引量:7
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作者 吴建明 李杨瑞 +3 位作者 王爱勤 杨柳 杨丽涛 甘崇琨 《分子植物育种》 CAS CSCD 2009年第5期922-927,共6页
本研究以喷清水甘蔗幼茎作为对照(即未处理),经过赤霉素处理后6h、12h、24h和48h的甘蔗幼茎为处理,分别进行取样并提取RNA,反转录获得cDNA作模板,利用SYBR GreenⅠ成功构建了目的基因(GA20-oxidase)和内参基因(GAPDH)的标准品和标准曲... 本研究以喷清水甘蔗幼茎作为对照(即未处理),经过赤霉素处理后6h、12h、24h和48h的甘蔗幼茎为处理,分别进行取样并提取RNA,反转录获得cDNA作模板,利用SYBR GreenⅠ成功构建了目的基因(GA20-oxidase)和内参基因(GAPDH)的标准品和标准曲线。结果表明:内参基因与目的基因的起始模板浓度与Ct之间呈良好线性关系,决定系数分别为r2=0.998、r2=0.995;溶解曲线均显单峰型,证明扩增的特异性比较好,可对基因表达进行相对定量。定量结果表明:目的基因未处理的表达量最大,赤霉素处理后表达量持续下降,在6h达到最低值,12h后逐渐上升,但到48h又明显下降,且所有处理的表达量均低于未处理,6h、12h、24h和48h比对照的表达量分别下降了24.75%、13.18%、10.23%和20.34%。本实验研究GA20-oxidase基因在赤霉素处理后的表达情况,为进一步克隆甘蔗GA20氧化酶基因全长序列、研究该基因在甘蔗节间伸长过程中的表达调控及甘蔗茎间伸长中的作用机理提供理论依据。 展开更多
关键词 甘蔗 GA20-氧化酶 赤霉素 定量PCR 基因表达
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