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Polyphenol Oxidase, Peroxidase and PhenylalanineAmmonium Lyase Induced in Postharvest Peach Fruitsby Inoculation with Pichia membranefaciensor Rhizopus stolonifer 被引量:13
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作者 QIN Guo-zheng, TIAN Shi-ping, LIU Hai-bo and XU Yong(Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany , Chinese Academy of Sciences , Beijing 100093 , P. R. China) 《Agricultural Sciences in China》 CAS CSCD 2002年第12期1370-1375,共6页
Rhizopus rot of peach fruits could be significantly suppressed by Pichia membranefaciens. Polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonium-lyase (PAL) activities induced by inoculation with P. mem... Rhizopus rot of peach fruits could be significantly suppressed by Pichia membranefaciens. Polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonium-lyase (PAL) activities induced by inoculation with P. membrane faciens or R. stolonifer were studied in postharvest peach fruits. The activities of PPO and PAL in peaches increased significantly after being inoculated with P. membrane faciens + R. stolonifer by 24 h, the activities maintained at a high level throughout the experiment. Under the condition of infected with R. stolonifer alone, activity of PPO and PAL could also increased, but the levels were lower than those treated with P. membrane faciens+ R. stolonifer. However, fruits inoculaed with P. membrane-faciens + R. stolonifer or R. stolonifer alone did not stimulated POD activity. The results suggest that the activation of these defense enzymes is involved in the action of P. membrane faciens against R. stolonifer. 展开更多
关键词 Peach fruits polyphenol oxidase PERoxidase Phenylalanine ammonium-lyase Pichia membranefaciens Rhizopus stolonifer
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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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Effects of Terpinen-4-ol on Four Metabolic Enzymes and Polyphenol Oxidase (PPO) in Mythimna separta Walker 被引量:4
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作者 MA Zhi-qing HAN Xiu-ling FENG Jun-tao LI Guang-ze ZHANG Xing 《Agricultural Sciences in China》 CAS CSCD 2008年第6期726-730,共5页
To study insecticidal mechanism of terpinen-4-ol, a main insecticidal composition in the essential oil of Sabina vulgaris, the 5th instar larvae of Mythimna separta, were investigated with terpinen-4-ol by topical app... To study insecticidal mechanism of terpinen-4-ol, a main insecticidal composition in the essential oil of Sabina vulgaris, the 5th instar larvae of Mythimna separta, were investigated with terpinen-4-ol by topical application. The activities of phosphatase, glutathione S-transferase (GSTs), cytochrome P450 (P450), and polyphenol oxidase (PPO) of tested insects were determined in all poisoning stages, including exciting stage, convulsing stage, paralysis stage, and recover stage. The result showed that the activities of both acid phosphatase (ACP) and alkaline phosphatase (AKP) in treated insects were induced by terpinen-4-ol, but ACP was inhibited in paralysis stage. The activities of GSTs were inhibited in exciting stage, convulsing stage, and paralysis stage, but gradually recovered in recover stage. O-demethylase activity of cytochrome P450 was inhibited by terpinen-4-ol, and the inhibition rate in all poisoning stages were 26.27, 46.03, 80.24, and 90.22%, respectively. PPO activities were strongly inhibited by terpinen-4-ol both in vitro and in vivo. In conclusion, the activities of P450, GSTs, and PPO could have relation with toxicity of terpinen-4-ol against larvae of the Mythimna separta, but recover stage of the poisoning insects might be related to GSTs induced. As a new insecticide or synergist, terpinen- 4-ol has a potential value in field of insecticide resistance management. 展开更多
关键词 TERPINEN-4-OL Mythimna separate polyphenol oxidase (PPO) metabolic enzymes insecticidal mechanism
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Study on Enzymatic Kinetics of Nephelium lappaceum Polyphenol Oxidase 被引量:2
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作者 Lunpei LIU Wenhua ZHANG 《Agricultural Biotechnology》 CAS 2012年第4期39-42,共4页
[Objective] This study aimed to investigate the enzymatic kinetics of polyphenol oxidase in peel of Nephelium lappaceum to explore the environmental factors affecting its catalytic activity. [ Method ] With N. lappace... [Objective] This study aimed to investigate the enzymatic kinetics of polyphenol oxidase in peel of Nephelium lappaceum to explore the environmental factors affecting its catalytic activity. [ Method ] With N. lappaceum peel as the experimental material and catechol as substrate, effects of temperature, pH, four inhibitors (EDTA, Vc, sodium bisulfite and citric acid) and substrate concentration on the activity of polyphenol oxidase were investigated. [ Result] The optimal temperature for polyphenol oxidase in N. lappaceum peel was 40 %, and the optimal pH was 6.8. EDTA, Vc, sodium bisulfite and citric acid all showed ideal in- hibitory effects on the activity of polyphenol oxidase; specifically, EDTA had the strongest inhibitory effect. [ Conclusion] At low temperature, EDTA, Vc, sodi- um bisulflte and citric acid with certain concentrations can inhibit the catalytic activity of polyphenol oxidase in peel of N. lappaceum, extend the storage and trans- portation time of N. lappaceum fruit, and inhibit the browning. This study provides theoretical basis for the development and utilization of polyphenol oxidase in peel of N. lappaceum. 展开更多
关键词 Nephelium lappaceum polyphenol oxidase Enzymatic kinetics
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Polyphenol Oxidase Activity and Inhibition in White Yam (Dioscorea Rotundata. Var. Laasirin) Chips as African Fries for Human Consumption 被引量:1
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作者 Oluwatoyin Oluwole Olajumoke Odediran +6 位作者 Gbolahan Alagbe Ijeoma Eboagwu Abimbola Jegede Kayode Ogundeji Abimbola Olokoshe Godfrey Asieba Joy Onyibe 《Journal of Food Science and Engineering》 2016年第1期43-50,共8页
Polyphenol oxidase, a bi-functional enzyme, has been implicated in enzymatic browning of yam and other tubers in a negative way. The objective of this present study was to examine the activity of polyphenol oxidase in... Polyphenol oxidase, a bi-functional enzyme, has been implicated in enzymatic browning of yam and other tubers in a negative way. The objective of this present study was to examine the activity of polyphenol oxidase in Dioscorea rotundata. Var. laasirin and the efficiency of heat and chemical treatments in inhibiting this enzyme. Crude Polyphenol Oxidase (PPO) of Dioscorea rotundata.Var. Laasirin was isolated and the kinetics studied using the lineweaver-burk plot. The activity of the enzyme was evaluated using spectrophotomeric method. Yam PPO catalyzes oxidation of various substrates with catechol being the most readily oxidized substrate. The Michaelis-Menten constant (Km) and maximum reaction velocity (Vmax) for yam PPO were 0.00037 and 0.3125 respectively. Inhibition data showed that the enzyme had least activity (71.70) when blanched at 95℃ for 7 mins with chemical treatment involving a combination of 0.5% Sodium metabisulphite (Food grade) and 0.5% Ascorbic acid (Food grade). The activity was highest (83.02) when it was blanched at 95 ℃ for 7 rains. This study has shown that it is possible to inhibit polyphenol oxidase activity in white yam using the chemical pretreatments and processing conditions described in this study for possible adoption in the production of packaged frozen yam chips by food industries. 展开更多
关键词 YAM polyphenol oxidase dioscorea rotundata blanch SULPHITE chips.
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Immobilization and Properties of Polyphenol Oxidase
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作者 Zheng LI Pan WANG +4 位作者 Yanxi SHEN Mingfei WEI Yimin HE Aoyu JI Jianfeng ZHAN 《Agricultural Biotechnology》 CAS 2021年第6期79-83,共5页
[Objectives]This study was conducted to investigate the effects of embedding conditions on activity and catalytic properties of immobilized polyphenol oxidase.[Methods]Polyphenol oxidase was immobilized in a polymer m... [Objectives]This study was conducted to investigate the effects of embedding conditions on activity and catalytic properties of immobilized polyphenol oxidase.[Methods]Polyphenol oxidase was immobilized in a polymer material by the embedding method,and the optimal immobilization conditions were obtained by single factor tests:CaCl_(2) concentration 2.0%,sodium alginate concentration 2.0%,immobilization time 2 h and mass ratio of enzyme to carrier 10 mg/100 g,under which the immobilized enzyme activity was 93.33 U/g.Under the above conditions,the properties of polyphenol oxidase immobilized by sodium alginate(A-PPO)and free polyphenol oxidase were studied.[Results]The thermostability of A-PPO was better than that of the free enzyme,but the pH stability of A-PPO was inhibited.The Michaelis constant K_(m) values of free polyphenol oxidase and A-PPO were 0.37 and 0.48 mmol/L,respectively,and the maximum reaction rate V_(max) values were 0.38 and 0.51 mmol/(L·g),respectively.[Conclusions]This study provides a theoretical basis for the study of the properties of polyphenol oxidase. 展开更多
关键词 polyphenol oxidase Immobilized enzyme Sodium alginate Enzymatic properties Kinetic parameter
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Kinetics of Inhibition of Polyphenol Oxidase Obtained from Tobacco Nicotiana Tobacum 被引量:4
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作者 刘卫群 饶学明 +1 位作者 潘继承 周海梦 《Tsinghua Science and Technology》 SCIE EI CAS 2004年第1期94-97,共4页
In this study, the kinetics of inhibition of polyphenol oxidase by L-cysteine has been investigated. The inhibition of tobacco polyphenol oxidase was studied using the progress-of-substrate-reaction method proposed by... In this study, the kinetics of inhibition of polyphenol oxidase by L-cysteine has been investigated. The inhibition of tobacco polyphenol oxidase was studied using the progress-of-substrate-reaction method proposed by Tsou, following the substrate reaction during irreversible inhibition of the enzyme activity. Analysis of the inhibition kinetics shows that inhibition occurs by an irreversible and non-complexation reaction. The microscopic rate constants were determined for reaction of the inhibitor both with the free enzyme and with the enzyme-substrate complex. The results show that the presence of the substrate has a significant protective effect of the enzyme against inactivation by L-cysteine. 展开更多
关键词 TOBACCO polyphenol oxidase KINETICS irreversible inhibition
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Inhibitory Kinetics of p-Substituted Benzaldehydes on Polyphenol Oxidase from the Fifth Instar of Pieris Rapae L. 被引量:1
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作者 王勤 柯莉娜 +2 位作者 薛超彬 罗万春 陈清西 《Tsinghua Science and Technology》 SCIE EI CAS 2007年第4期400-404,共5页
Polyphenol oxidase (PPO) is the enzyme responsible for enzymatic browning during the growth of insects. It is also involved in defense reactions and is related with immunities in insects. PPO a metalloenzyme oxidase... Polyphenol oxidase (PPO) is the enzyme responsible for enzymatic browning during the growth of insects. It is also involved in defense reactions and is related with immunities in insects. PPO a metalloenzyme oxidase, catalyzes the oxidation of o-diphenol to o-quinone. The present paper describes the effects of benzaldehyde and its p-substituted derivatives on the activity of PPO from the fifth instar of Pieris rapae L. PPO from the fifth instar of Pieris rapae L. was purified using ammonium sulfate fractionation and chromatography on Sephadex G-100. The enzyme kinetics was characterized using L-3,4-dihydroxyphenylalanine (L-DOPA) as substrate. The results show that benzaldehyde, phydroxybenzaldehyde, p-chlorobenzaldehyde, and p-cyanobenzaldehyde can inhibit the PPO activity for the oxidation of L-DOPA. The inhibitor concentration leading to 50% activity lost, IC50, was estimated to be 5.90, 5.62, 2.83, and 2.91 mmol/L for the four tested inhibitors, respectively. Kinetic analyses show that the inhibitory effects of these compounds are reversible. Benzaldehyde, phydroxybenzaldehyde, and p-chlorobenzaldehyde are noncompetitive inhibitors while p-cyanobenzaldehyde is a mixed-type inhibitor. The inhibition constants were determined for all four inhibitors. p-chlorobenzaldehyde and p-cyanobenzaldehyde were more potent inhibitors than the other compounds. These results provide a basis for developing PPO inhibition-based pesticides. 展开更多
关键词 Pieris rapae L. the fifth instar polyphenol oxidase BENZALDEHYDE p-substituted derivatives inhibition inhibitory type kinetics mechanism
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Polyphenolic Compound and the Degree of Browning in Processing Apple Varieties 被引量:17
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作者 SONG Ye YAO Yu-xin +3 位作者 ZHAI Heng DU Yuan-peng CHEN Feng WEI Shu-wei 《Agricultural Sciences in China》 CAS CSCD 2007年第5期607-612,共6页
Polyphenolic compound in processing apple (Malus domestica Borkh.) varieties and the relationship between polyphenol content and enzymatic browning were studied to provide reference for raw material selection and pr... Polyphenolic compound in processing apple (Malus domestica Borkh.) varieties and the relationship between polyphenol content and enzymatic browning were studied to provide reference for raw material selection and processing method optimization. The content of polyphenol compound in 10 processing apple varieties (4 cider and 6 juice varieties) were analyzed using the Folin-Ciocalteu method and HPLC. The degree of browning and the activities of polyphenol oxidase were also studied. The content and proportion of the polyphenol varied depending on the variety. Bitter varieties globally showed a higher polyphenol concentration than sweet or acid varieties. Proanthocyanidins, chlorogenic acid, (+)-catechin, (-)-epicatechin were high-concentrated polyphenols in apple fruits. Phloridzin, the unique polyphenol of apple, was abundant in the bitter variety Frequin rouge fruit. Total polyphenols, proanthocyanidins, (+)-catechin, and phloridzin had higher correlations with browning. The correlation was low between chlorogenic acid and browning. The polyphenolic profiles were correlated with the apple types. Cider apples contained more polyphenol than juice apple varieties. The content of flavan-3-ol has a close relationship with fruit browning. 展开更多
关键词 APPLE processing varieties polyphenolic compounds BROWNING polyphenol oxidase
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Effects of Altitude on Polyphenols Contents in Cigar Leaves 被引量:2
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作者 LIU Bo-yuan CHEN Yong-wei +2 位作者 JIN Ming-ke YANG Wei-li ZHAO Ming-qin 《Agricultural Science & Technology》 CAS 2020年第4期15-22,共8页
Elevation affects the contents of polyphenols involved in the plants’resistance to the environment.In this study,polyphenolic contents,as well as the activity of polyphenol oxidase(PPO),were evaluated in mature cigar... Elevation affects the contents of polyphenols involved in the plants’resistance to the environment.In this study,polyphenolic contents,as well as the activity of polyphenol oxidase(PPO),were evaluated in mature cigar plants at different elevation levels.The results showed that:(1)The contents of chlorogenic acid,rutin,and scopolamine in cigar leaves increased gradually at all elevation levels,reaching a maximum 25 d after the mature stage.(2)With an increase in altitude,the polyphenolic compounds’contents increased,having the lowest values at 350 m height and the highest at 1090 m height.(3)As for the PPO activity in cigar leaves,the general trend showed an increase first followed by a decrease in activity during the mature period.(4)PPO activity in the leaves of cigar plants planted at 840 m height was substantially elevated compared to those growing at 600 m and 350 m height.Interestingly,the leaves planted at 1090 m height had the lowest PPO activity.(5)There were significant positive correlations between altitude and the contents of chlorogenic acid,rutin,and scopolamine within the plants leaves.Altitude negatively correlated the proportion of chlorogenic acid and scopolamine whereas positively correlated rutin proportion within the total polyphenols.Temperature had negative correlations with the contents of chlorogenic acid,rutin,and scopolamine,while sunlight intensity had positive correlations on their contents.Conversely,there were no significant correlations between altitude,temperature,and light intensity on PPO activity.Therefore,this study can provide valuable insight and a theoretical basis for the production of premium cigars. 展开更多
关键词 CIGAR ELEVATION Light intensity polyphenolS polyphenol oxidase
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Agrobacterium tumefaciens-mediated transformation of embryogenic callus and CRISPR/Cas9-mediated genome editing in‘Feizixiao'litchi 被引量:8
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作者 Shujun Wang Guo Wang +2 位作者 Huanling Li Fang Li Jiabao Wang 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第5期947-957,共11页
Litchi(Litchi chinensis Sonn.)is a type of commercially prevalent subtropical and tropical fruit.Since litchi has a highly heterozygous genetic background and a long reproductive cycle,conventional breeding methods(su... Litchi(Litchi chinensis Sonn.)is a type of commercially prevalent subtropical and tropical fruit.Since litchi has a highly heterozygous genetic background and a long reproductive cycle,conventional breeding methods(such as hybridization)have limited ability to nurture new litchi cultivars.Here,an efficient and stable Agrobacterium tumefaciens-mediated genetic transformation of embryogenic callus was established in‘Feizixiao’litchi.Transgenic materials were verified using polymerase chain reaction(PCR)analysis,β-glucuronidase(GUS)assay,and green fluorescent protein(GFP)assay.To implement the technology of the Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR)/associated protein 9(CRISPR/Cas9)technology in‘Feizixiao’litchi and verify the validity of these transformation systems,the litchi polyphenol oxidase gene(LcPPO,JF926153)was knocked out.Various categories of mutations,covering base insertions,deletions,and substitutions,were found in transgenic materials via sequence analysis.The transformation system achieved high feasibility and efficiency,and the system of CRISPR/Cas9 was successfully employed to edit genes in‘Feizixiao’litchi.This work provides an essential foundation for investigating the functions of genes and accelerating litchi genetic improvement. 展开更多
关键词 LITCHI Litchi chinensis Sonn Genetic transformation Gene editing polyphenol oxidase(PPO)
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Widely Untargeted Metabolome Profiling Provides Insight into Browning and Nutritional Quality Changes in Short-Term Stored Fresh-Cut Potato(Solanum tuberosum L.)Shreds
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作者 Liping Hong Enming He +3 位作者 Wenhui Zhang Mingqiong Zheng Jingwen Wu Wenhua Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第10期2785-2805,共21页
Potato(Solanum tuberosum L.)is susceptible to enzymatic browning after fresh processing,resulting in color change and potential alteration in the nutritional quality.In this study,a popular potato cultivar,Feiwuruita,... Potato(Solanum tuberosum L.)is susceptible to enzymatic browning after fresh processing,resulting in color change and potential alteration in the nutritional quality.In this study,a popular potato cultivar,Feiwuruita,was used to profile the metabolites involved in color and nutritional quality changes in fresh shreds stored at 0 and 4 h at 25°C(designated CK and CK4H,respectively).The shreds turned brown within 4 h of storage.In all,723 metabolites consisting 12 classes of compounds were detected in the samples,largely lipids,phenolic acids,alkaloids,amino acids and derivatives,flavonoids,organic acids,nucleotides and derivatives.Of these,163 metabolites accumulated differentially between CK and CK4H shreds.Polyphenolic compounds(phenolic acids and flavonoids)mostly increased in the shreds after 4 h storage.Conversely,the short-term storage drastically reduced lipid compounds(25 LysoPC and 19 LysoPE),while essential alkaloids and terpenoid compounds that are beneficial to human health increased in accumulation.The findings present global metabolome and nutritional composition changes in short-term stored shreds of Feiwuruita.This study provides important foundation for future studies on browning prevention/reduction and for better utilization of Feiwuruita. 展开更多
关键词 Enzymatic browning colorimetric values METABOLITES phenylpropanoid biosynthesis polyphenol oxidases activity
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Enzyme Solutions and H_2O_2 on Somatic Embryogenesis of Fraxinus mandshurica Rupr. (Oleaceae) 被引量:1
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作者 孙倩 杨玲 +1 位作者 沈海龙 李玉花 《Agricultural Science & Technology》 CAS 2012年第8期1716-1721,共6页
[Objective] This study aimed to explore the effects of treatments with three types of exogenous oxidase solutions and H2O2.solution on the somatic embryogenesis of Fraxinus mandshurica Rupr. (Oleaceae). [Method] The... [Objective] This study aimed to explore the effects of treatments with three types of exogenous oxidase solutions and H2O2.solution on the somatic embryogenesis of Fraxinus mandshurica Rupr. (Oleaceae). [Method] The immature zygotic cotyledons were treated with PPQ (polyphenol oxidase) solution, GQD (glucose oxidase) solution, SOD (superoxide dismutase) solution and H202 (hydrogen peroxide) at different concentrations to explore the effects on the growth, browning and somatic embryogenesis on cotyledon explants in the somatic embryogenesis of F. mandshurica. Through comparative analysis on the effects of different treatments on somatic embryogenesis of F. mandshurica, the relationship between explants browning and somatic embryogenesis was uncovered during the somatic embryogenesis of F. mandshurica. [Result] H2O2 treatment not only advanced the explants browning, but also inhibited the growth and somatic embryogenesis of explants; different concentrations of PPQ promoted the growth and browning of explants, as well as improving the incidence of somatic embryogenesis; both GOD and SOD treatment could raise the explants browning rate; when somatic embryogenesis of explants treated with enzyme solutions advanced, the incidence of somatic embryogenesis was low; however, when the disparity of the incidence of somatic embryogenesis between 30 and 60 d treatments reached its peak, the incidence of somatic embryogenesis was also high. [Conclusion] The results of this study provide basis for raising the incidence and improving the status of somatic embryogenesis of F. mandshurica, as well as optimizing the somatic embryogenesis system of F. mandshurica. 展开更多
关键词 Fraxinus mandshurica Rupr. (Oleaceae) Somatic embryogenesis polyphenol oxidase Glucose oxidase Superoxide dismutase Hydrogen peroxide
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Study on Processing of Clear Banana Juice Using Hot Water Extraction Method 被引量:2
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作者 郑欣 余元善 +4 位作者 吴继军 徐玉娟 肖更生 黄婉华 温靖 《Agricultural Science & Technology》 CAS 2014年第11期2003-2005,2044,共4页
In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase (PPO) and color of banana juice during hot water ex-traction were discussed based on the theory in which heat ... In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase (PPO) and color of banana juice during hot water ex-traction were discussed based on the theory in which heat treatment might induce the pectin and protein in banana pulp to form insoluble products. The results showed the hot water temperature had a significant effect on the formation of insol-uble polymers in banana pulp from pectin and protein. In 75 ℃ water, the pectin and protein in banana pulp were most inclined to form insoluble products. Under this condition, the clarity of banana juice was also highest. The light transmittance at 660 nm was close to 90%. In the banana juice, extracted by 75 ℃ water, the pectin and protein contents were lowest, and they were lower than 7.3 mg/100 ml and 12.9 mg/100 ml respectively. The 75 ℃ water could not inactivate completely the pectin in banana pulp due to its high heat resistance, Therefore, 0.05% L-cys-teine or ascorbic acid needed to be added into banana pulp to inhibit the browning of juice induced by residual PPO. 展开更多
关键词 Clear banana juice Hot water extraction polyphenol oxidase Pectin Protein
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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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Prediction Model of Secondary Substances in Anthocyanins Synthesis of Purple Corn
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作者 朱敏 史振声 +1 位作者 李凤海 王志斌 《Agricultural Science & Technology》 CAS 2010年第8期153-156,182,共5页
The aim of this study was to assay the polyphenols,flavonoid,polyphenol oxidase and phenylalnine ammonialyase which were relative to the anthocyanins synthesis of purple corn. The optimization of multiple linear regre... The aim of this study was to assay the polyphenols,flavonoid,polyphenol oxidase and phenylalnine ammonialyase which were relative to the anthocyanins synthesis of purple corn. The optimization of multiple linear regression model of anthocyanins synthesis was y=4.383 86-0.205 45x1+5.479 638x2+0.195 575x4. According to standard partial regression coefficient testing,the result indicated that polyphenols content was negatively correlated with anthocyanins and the relative influence to anthocyanins synthesis was-42.7%; flavonoid content and activity of polyphenol oxidase were positively correlated with anthocyanins of purple corn and the relative influence to anthocyanins synthesis were 71.45% and 73.32% respectively. There was no positive correlation between the activity of phenylalnine ammonialyase and anthocyanins of purple corn. The establishment of multiple linear regression model of anthocyanins synthesis was to provide theory foundation of producing anthocyanins in laboratory. 展开更多
关键词 Anthocyanins Flavonoid Multiple linear regression model Purple corn polyphenolS polyphenol oxidase Phenylalnine ammonialyase
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Relationship between the Hypersensitive Response of Wheat to Blumeria graminis f. sp. tritici and Hydrogen Peroxide,Three Enzyme Activities Changes
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作者 李映霞 余冬冬 +3 位作者 喻大召 杨立军 郭佳佳 黄俊斌 《Agricultural Science & Technology》 CAS 2010年第2期57-60,共4页
[Objective] The research aimed to study the relationship between the hypersensitive response of wheat to Blumeria graminis f.sp.tritici and hydrogen peroxide,3 enzyme activities changes and lay the foundation for disc... [Objective] The research aimed to study the relationship between the hypersensitive response of wheat to Blumeria graminis f.sp.tritici and hydrogen peroxide,3 enzyme activities changes and lay the foundation for discussing the resistant physiological mechanism of wheat to B.graminis.[Method] Taking B.graminis Bgt 17 and Bgt 6 and wheat cultivar Yang 158 as test materials,the number of hypersensitive cells and activities of POD,PPO and SOD in wheat leaves treated by H2O2 were determined.[Result] The mastoid... 展开更多
关键词 Blumeria graminis f.sp.tritici H2O2 PERoxidase polyphenol oxidase Supperoxide dismutase
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Effects of Used Battery on Key Enzyme Activity during the Germination of Wheat Seeds
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作者 张恒 许兆棠 +2 位作者 李帅庆 韩玉良 陈智 《Agricultural Science & Technology》 CAS 2013年第1期135-137,143,共4页
[Objective] This study aimed to explore the effects of used battery lixivium on wheat germination. [Method] The wheat seeds were treated with used battery lix- ivium at different concentrations to detect the change of... [Objective] This study aimed to explore the effects of used battery lixivium on wheat germination. [Method] The wheat seeds were treated with used battery lix- ivium at different concentrations to detect the change of activities of amylase, pro- tease, pyruvate dehydrogenase (PDH) and polyphenol oxidase (PPO) during the ger- mination period. [Result] The results showed that the used battery affected enzyme activity. With the increase of concentration of used battery lixivium, trends of the changes of amylase and protease activities were not different. The activities were en- hanced at low concentrations of lixivium, while were inhibited at high concentrations. The tends of changes of pyruvate dehydrogenase (PDH) and polyphenol oxidase (PPO) activities were not consistent with that of either amylase or protease, which showed continuous downward trends with the increasing concentration of used battery lixivium. [Conclusion] This study is of great practical significance for understanding the effects of used battery lixivium on the germination of wheat seeds. 展开更多
关键词 Used battery lixivium Germination of wheat seeds Activities of amylase protease pyruvate dehydrogenase(PDH) and polyphenol oxidase(PPO)
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Response dynamics of three defense related enzymes in cotton leaves to the interactive stress of Helicoverpa armigera (Hübner) herbivory and omethoate application 被引量:3
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作者 SHA Pin-jie FAN Yin-jun +1 位作者 WANG Zhi-chao SHI Xue-yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第2期355-364,共10页
In order to explore the response dynamics of the activities of defense related enzymes in cotton leaves towards the interactive stress of Helicoverpa armigera herbivory and omethoate application, the activities of phe... In order to explore the response dynamics of the activities of defense related enzymes in cotton leaves towards the interactive stress of Helicoverpa armigera herbivory and omethoate application, the activities of phenylalanine ammonia-lyase(PAL), lipoxygenase(LOX), and polyphenol oxidase(PPO) were examined from 6 to 126 h after cotton leaves were treated 12 h of H. armigera herbivory, and then sprayed with 800 mg L–1 omethoate. The results showed that the changes in the activities of PAL, LOX and PPO that occured under the interactive stress of H. armigera herbivory and omethoate application reflected the interactive effects of the two stresses on cotton defense. The similarity between the response dynamics of PAL, LOX, and PPO activities in cotton leaves under the interactive stress and that under H. armigera herbivory treatment alone showed that the induction of H. armigera herbivory on the activities of PAL, LOX and PPO in cotton leaves played a leading role in the interactive effects, and the effect of omethoate application played only a minor role. A joint factor analysis was performed according to a method which has been used to analyze the joint toxicity of pesticides; this analysis sought to clarify if there was a synergistic, antagonistic, or additive effect on PAL, LOX, and PPO activity in cotton leaves resulting from the interactive H. armigera herbivory and omethoate treatment. In the interactive effect on the response of PAL activity in cotton leaves, antagonistic effects of the omethoate application towards H. armigera herbivory were observed at 6 and 12 h. Synergistic effects were then observed at 18 and 30 h. Antagonistic effects were observed from 54 to 78 h and synergistic effects were finally observed at 126 h. The correlation between H. armigera herbivory and omethoate application in the interactive effect on cotton defense responses of LOX activity also fluctuated from synergism to antagonism during the time course. In the interactive effect on PPO activity, only antagonism was observed between H. armigera herbivory and omethoate application. In the interactive stress of H. armigera herbivory and omethoate application on cotton defense responses, omethoate affected the defense responses of cotton to H. armigera herbivory by producing antagonistic and synergistic effects. These results will be useful to understand the relationship between host plant and herbivorous pest. 展开更多
关键词 cotton defense Helicoverpa armigera herbivory OMETHOATE phenylalanine ammonia-lyase LIPOXYGENASE polyphenol oxidase
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Study on the Control of Tobacco Black Shank by Using Dry Mycelium of Penicillium Chrysogenum 被引量:12
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作者 Changliang Xu Rong Zeng +5 位作者 Chunsheng Ruan Xiaoxia Wang Kaibao Xia George McBride Jianpeng Luo Suiyun Chen 《Journal of Life Sciences》 2010年第1期1-6,共6页
The water extract of dry mycelium ofPenicillium chrysogenum (DME) was used to induce resistance in Virginia tobacco plants against Phtophthora parasitica var. nicotianae. Results showed that the efficacy of DME in c... The water extract of dry mycelium ofPenicillium chrysogenum (DME) was used to induce resistance in Virginia tobacco plants against Phtophthora parasitica var. nicotianae. Results showed that the efficacy of DME in controlling black shank disease depended on both DME solution concentration and its' treatment methodology. Soil application of 1.5-5% DME 72 hr before inoculation with Phtophthora parasitica vat. nicotianae provided highly significant protection against black shank, relative to the control without DME treatment. Optimized tobacco plant treatment with 2.5% DME significantly increased peroxidase (POD) and polyphenol oxidase (PPO) activity levels in the upper leaf sections of the tobacco plants. DME had no direct antifungal activity on the growth of Phtophthora parasitica var. nicotianae in vitro, suggesting that disease control with DME treatment resulted from the induced propagation of natural defense mechanisms in the tobacco plants. 展开更多
关键词 Water extract of dry mycelium ofPenicillium chrysogenum (DME) tobacco black shank peroxidase (POD) polyphenol oxidase (PPO).
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