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农业微生物；产业发展；微生物肥料；饲用微生物；微生物农药；酶制剂微生物；微生物种业 1

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Study of simultaneous saccharification and fermentation for steam exploded wheat straw to ethanol

LUO Peng, YANG Chuanmin, LIU Zhong, WANG Gaosheng

《化学科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 447-451 doi: 10.1007/s11705-008-0069-1

摘要： Although simultaneous saccharification and fermentation (SSF) has been investigated extensively, the optimum condition for SSF of wheat straw has not yet been determined. Dilute sulfuric acid impregnated and steam explosion pretreated wheat straw was used as a substrate for the production of ethanol by SSF through orthogonal experiment design in this study. Cellulase mixture (Celluclast 1.5 l and -glucosidase Novozym 188) were adopted in combination with the yeast AS2.1. The effects of reaction temperature, substrate concentration, initial fermentation liquid pH value and enzyme loading were evaluated and the SSF conditions were optimized. The ranking, from high to low, of influential extent of the SSF affecting factors to ethanol concentration and yield was substrate concentration, enzyme loading, initial fermentation liquid pH value and reaction temperature, respectively. The optimal SSF conditions were: reaction temperature, 35°C; substrate concentration, 100 g·L; initial fermentation liquid pH, 5.0; enzyme loading, 30 FPU·g. Under these conditions, the ethanol concentration increased with reaction time, and after 72 h, ethanol was obtained in 65.8% yield with a concentration of 22.7 g·L.

关键词： optimal SSF     substrate concentration     optimum condition     enzyme loading     ethanol concentration    

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Designer enzyme for green materials innovation: Lactate-polymerizing enzyme as a key catalyst

Seiichi Taguchi

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 139-142 doi: 10.1007/s11705-017-1636-0

摘要： Establishment of the regeneratable whole-cell catalyst platform for the?production of biobased polymeric materials is a?typical topic of synthetic biology. In this commentary, discovery story of a “lactate-polymerizing enzyme” (LPE)?and LPE-based?achievements for creating a new variety of polyesters with incorporated unnatural monomers are presented. Besides the importance of microbial platform itself is discussed referring to the “ballooning”- .

关键词： synthetic biology     enzyme evolutionary engineering     polyhydroxyalkanoate    

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Influence of glucose feeding on the ligninolytic enzyme production of the white-rot fungus Phanerochaete

ZHOU Xiaoyan, WEN Xianghua, FENG Yan

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 89-94 doi: 10.1007/s11783-007-0017-1

摘要： The present work studied the influence of glucose feeding on the ligninolytic enzyme production of in a nitrogen-limited (C/N ratio is 56/8.8 mmol/L) medium. Several sets of shaking flask experiments were conducted. The results showed that 2 g/L glucose feeding on the first day of the culture (24 h after the inoculation) stimulated both fungal biomass growth and enzyme production. The manganese peroxidase (MnP) activity was 2.5 times greater than that produced in cultures without glucose feeding. Furthermore, the glucose feeding mode in fed-batch culture was also investigated. Compared to cultures with glucose feeding every 48 h, cultures with glucose feeding of 1.5 g/L (final concentration) every 24 h produced more enzymes. The peak and total yield of MnP activity were 2.7 and 3 times greater compared to the contrast culture, respectively, and the enzyme was kept stable for 4 days with an activity of over 200 U/L.

关键词： enzyme production     fed-batch culture     nitrogen-limited     inoculation     mmol/L    

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Diffusion process in enzyme–metal hybrid catalysts

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 921-929 doi: 10.1007/s11705-022-2144-4

摘要： Enzyme–metal hybrid catalysts bridge the gap between enzymatic and heterogeneous catalysis, which is significant for expanding biocatalysis to a broader scope. Previous studies have demonstrated that the enzyme–metal hybrid catalysts exhibited considerably higher catalytic efficiency in cascade reactions, compared with that of the combination of separated enzyme and metal catalysts. However, the precise mechanism of this phenomenon remains unclear. Here, we investigated the diffusion process in enzyme–metal hybrid catalysts using Pd/lipase-Pluronic conjugates and the combination of immobilized lipase (Novozyme 435) and Pd/C as models. With reference to experimental data in previous studies, the Weisz–Prater parameter and efficiency factor of internal diffusion were calculated to evaluate the internal diffusion limitations in these catalysts. Thereafter, a kinetic model was developed and fitted to describe the proximity effect in hybrid catalysts. Results indicated that the enhanced catalytic efficiency of hybrid catalysts may arise from the decreased internal diffusion limitation, size effect of Pd clusters and proximity of the enzyme and metal active sites, which provides a theoretical foundation for the rational design of enzyme–metal hybrid catalysts.

关键词： enzyme–metal hybrid catalyst     internal diffusion     proximity effect     kinetic model    

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Detection of Escherichia coli in wastewater based on enzyme immunoassay

XI Haiyan, CAI Qiang, HE Miao, SHI Hanchang

《环境科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 381-384 doi: 10.1007/s11783-007-0065-6

摘要： This research describes a fast detection method on the basis of enzyme-linked immunosorbent assay (ELISA) for in drainage of wastewater treatment plants. Optimized conditions such as the reaction format (sandwich or direct), the concentrations of diluted horse radish peroxidase (HRP)- conjugate, and anti-HPR antibody and pretreatment of were studied. Those results showed that the linear range of detection for was 10 cfu/mL– 6 × 10 cfu/mL. Compared with conventional methods, it is a convenient and sensitive detection method with low cost.

关键词： conventional     sandwich     pretreatment     enzyme-linked immunosorbent     detection    

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Enzyme@bismuth-ellagic acid: a versatile platform for enzyme immobilization with enhanced acid-base stability

《化学科学与工程前沿（英文）》 2023年 第17卷 第6期   页码 784-794 doi: 10.1007/s11705-022-2278-4

摘要： In situ encapsulation is an effective way to synthesize enzyme@metal–organic framework biocatalysts; however, it is limited by the conditions of metal–organic framework synthesis and its acid-base stability. Herein, a biocatalytic platform with improved acid-base stability was constructed via a one-pot method using bismuth-ellagic acid as the carrier. Bismuth-ellagic acid is a green phenol-based metal–organic framework whose organic precursor is extracted from natural plants. After encapsulation, the stability, especially the acid-base stability, of amyloglucosidases@bismuth-ellagic acid was enhanced, which remained stable over a wide pH range (2–12) and achieved multiple recycling. By selecting a suitable buffer, bismuth-ellagic acid can encapsulate different types of enzymes and enable interactions between the encapsulated enzymes and cofactors, as well as between multiple enzymes. The green precursor, simple and convenient preparation process provided a versatile strategy for enzymes encapsulation.

关键词： bismuth-ellagic acid     in situ encapsulation     enzyme@MOF biocomposites    

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Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

《环境科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 218-223 doi: 10.1007/s11783-008-0037-5

摘要： To reveal the biological characteristics of urban forest soil and the effects of soil enzyme on soil fertility as well as the correlation between physicochemical properties and enzyme activities, 44 urban forest soil profiles in Nanjing were investigated. Basic soil physicochemical properties and enzyme activities were analyzed in the laboratory. Hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase were determined by potassium permanganate titration, TTC (CHN·Cl) colorimetry, phenyl phosphate dinatrium colorimetry, and anthrone colorimetry, respectively. The result showed that soil pH, organic carbon (C), and total nitrogen (N) had great effects on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 0–20 cm thick soil. However, pH only had great effect on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 20–40 cm thick soil. Hydrogen peroxidase, dehydrogenase, and alkaline phosphatase were important biological indicators for the fertility of urban forest soil. Both in 0–20 cm and 20–40 cm soil, soil enzyme system (hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase) had a close relationship with a combination of physicochemical indicators (pH, organic C, total N, available K, available P, cation exchange capacity (CEC), and microbial biomass carbon (C)). The more soil enzyme activities there were, the higher the fertility of urban forest soil.
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enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial loading

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1531-1544 doi: 10.1007/s11709-020-0675-7

摘要： Some of the current concrete damage plasticity models in the literature employ a single damage variable for both the tension and compression regimes, while a few more advanced models employ two damage variables. Models with a single variable have an inherent difficulty in accounting for the damage accrued due to tensile and compressive actions in appropriately different manners, and their mutual dependencies. In the current models that adopt two damage variables, the independence of these damage variables during cyclic loading results in the failure to capture the effects of tensile damage on the compressive behavior of concrete and vice-versa. This study presents a cyclic model established by extending an existing monotonic constitutive model. The model describes the cyclic behavior of concrete under multiaxial loading conditions and considers the influence of tensile/compressive damage on the compressive/tensile response. The proposed model, dubbed the enhanced concrete damage plasticity model (ECDPM), is an extension of an existing model that combines the theories of classical plasticity and continuum damage mechanics. Unlike most prior studies on models in the same category, the performance of the proposed ECDPM is evaluated using experimental data on concrete specimens at the material level obtained under cyclic multiaxial loading conditions including uniaxial tension and confined compression. The performance of the model is observed to be satisfactory. Furthermore, the superiority of ECDPM over three previously proposed constitutive models is demonstrated through comparisons with the results of a uniaxial tension-compression test and a virtual test.

关键词： damage plasticity model     plain concrete     cyclic loading     multiaxial loading conditions    

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Cofactor engineering in cyanobacteria to overcome imbalance between NADPH and NADH: A mini review

Jongmoon Park,Yunnam Choi

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 66-71 doi: 10.1007/s11705-016-1591-1

摘要： Cyanobacteria can produce useful renewable fuels and high-value chemicals using sunlight and atmospheric carbon dioxide by photosynthesis. Genetic manipulation has increased the variety of chemicals that cyanobacteria can produce. However, their uniquely abundant NADPH-pool, in other words insufficient supply of NADH, tends to limit their production yields in case of utilizing NADH-dependent enzyme, which is quite common in heterotrophic microbes. To overcome this cofactor imbalance and enhance cyanobacterial fuel and chemical production, various approaches for cofactor engineering have been employed. In this review, we focus on three approaches: (1) utilization of NADPH-dependent enzymes, (2) increasing NADH production, and (3) changing cofactor specificity of NADH-dependent enzymes from NADH to NADPH.

关键词： NADH-dependent enzyme     NADPH-dependent enzyme     transhydrogenase     site-directed mutagenesis     enzyme engineering    

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Reconsideration on the effect of nitrogen on mixed culture polyhydroxyalkanoate production toward high organic loading

Zhiqiang Chen, Lizhi Zhao, Ye Ji, Qinxue Wen, Long Huang

《环境科学与工程前沿（英文）》 2019年 第13卷 第4期 doi: 10.1007/s11783-019-1135-2

摘要：

Effect of nitrogen on mixed culture PHA production was reconsidered.

Enrichment history of PHA accumulating culture was discussed.

Higher PHA content and biomass growth were achieved in presence of nitrogen.

Enrichment strategy toward higher PHA accumulation was investigated.

Microbial community succession in PHA accumulation phase was investigated.

关键词： Polyhydroxyalkanoate (PHA)     Organic loading rate     Nitrogen content     Biomass growth     Enrichment history    

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Plant diversity reduces the effect of multiple heavy metal pollution on soil enzyme activities and microbial

Yang GAO, Chiyuan MIAO, Jun XIA, Liang MAO, Yafeng WANG, Pei ZHOU

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 213-223 doi: 10.1007/s11783-011-0345-z

摘要： It is unclear whether certain plant species and plant diversity could reduce the impacts of multiple heavy metal pollution on soil microbial structure and soil enzyme activities. Random amplified polymorphic DNA (RAPD) was used to analyze the genetic diversity and microbial similarity in planted and unplanted soil under combined cadmium (Cd) and lead (Pb) pollution. A metal hyperaccumulator, , and a common plant, , were used in this research. The results showed that microorganism quantity in planted soil significantly increased, compared with that in unplanted soil with Cd and Pb pollution. The order of microbial community sensitivity in response to Cd and Pb stress was as follows: actinomycetes>bacteria>fungi. Respiration, phosphatase, urease and dehydrogenase activity were significantly inhibited due to Cd and Pb stress. Compared with unplanted soil, planted soils have frequently been reported to have higher rates of microbial activity due to the presence of additional surfaces for microbial colonization and organic compounds released by the plant roots. Two coexisting plants could increase microbe population and the activity of phosphatases, dehydrogenases and, in particular, ureases. Soil enzyme activity was higher in phytoremediated soil than in planted soil in this study. Heavy metal pollution decreased the richness of the soil microbial community, but plant diversity increased DNA sequence diversity and maintained DNA sequence diversity at high levels. The genetic polymorphism under heavy metal stress was higher in phytoremediated soil than in planted soil.

关键词： enzyme activity     soil DNA     microbial population     plant diversity     heavy metal    

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Effect of loading rate on shear strength parameters of mechanically and biologically treated waste

《环境科学与工程前沿（英文）》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1595-7

摘要：

● Mechanical behavior of MBT waste affected by loading rate was investigated.

关键词： Mechanically and biologically treated waste     Landfill     Triaxial test     Loading rate     Axial strain     Shear strength parameter    

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Degradation of 4-aminophenol by hydrogen peroxide oxidation using enzyme from Serratia marcescens as

SUN Min, YOU Yahua, DENG Shengsong, GAO Wenxia, YAO Risheng

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 95-98 doi: 10.1007/s11783-007-0018-0

摘要： AB 90027 as catalyst. The effecting factors during degradation and the degrading mechanism were studied. Also, the location of the enzyme in the cell, which could catalyze the degradation of 4-aminophenol, was analyzed. The results showed that to degrade 50 mL of 4-aminophenol whose concentration was 500 mg/L, the optimal conditions were: volume of HO = 3 mL, temperature = 40 60?C and pH = 9 10. In the degradation process, 4-aminophenol was first converted to benzoquinone and NH, then organic acids including maleic acid, fumaleic acid, and oxalic acid were formed, and then finally CO and HO were generated as final products. The enzyme that could catalyze the degradation of 4-aminophenol was mainly extracellular enzyme.

关键词： degradation process     temperature     effecting     degradation     volume    

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Microcystin-LR detection based on indirect competitive enzyme-linked immunosorbent assay

SHENG Jianwu, HE Miao, YU Shaoqing, SHI Hanchang, QIAN Yi

《环境科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 329-333 doi: 10.1007/s11783-007-0056-7

摘要： Microcystins (MCs) are a group of closely related toxic cyclic heptapeptides produced by common cyanobacteria, which cause lots of accidents and threatens human health. In this paper, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) was established and used to detect microcystin-LR (MC-LR) in drinking and surface waters. The concentration of coating antigen was 5 ?g/mL, the dilution of monoclonal antibody MC10E7 was 1:3 000, the dilution of enzyme tracer (goat anti-mouse IgG-peroxidase) was 1:3 000, the standard concentration of MC-LR ranged from 0.001 μg/L to 30 μg/L, and o-phenylenediamine was used as substrate. The assay showed high relativity with high performance liquid chromatography (HPLC) with a correlation coefficient of more than 99%. The relative standard deviation was less than 10%, the detection limit was achieved down to 0.01 μg/L and up to 5.1 μg/L. The quantitative detection range was from 0.03 μg/L to 3 μg/L, and the antibody had high specificity for [4-arginine] microcystins. It performed well in spite of the influence of the real samples.

关键词： o-phenylenediamine     4-arginine     ic-ELISA     substrate     chromatography    

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Axisymmetric loading on nanoscale multilayered media

《结构与土木工程前沿（英文）》 2023年 第17卷 第1期   页码 152-164 doi: 10.1007/s11709-022-0895-0

摘要： Multilayered nanoscale structures are used in several applications. Because the effect of surface energy becomes nontrivial at such a small scale, a modified continuum theory is required to accurately predict their mechanical behaviors. A Gurtin–Murdoch continuum model of surface elasticity is implemented to establish a computational scheme for investigating an elastic multilayered system under axisymmetric loads with the incorporation of surface/interface energy. Each layer stiffness matrix is derived based on the general solutions of stresses and displacements obtained in the form of the Hankel integral transform. Numerical solutions to the global equation, which are formulated based on the continuity conditions of tractions and displacements across interfaces between layers, yield the displacements at each layer interface and on the top surface of the multilayered medium. The numerical solutions indicate that the elastic responses of multilayered structures are affected significantly by the surface material properties of both the top surface and interfaces, and that they become size dependent. In addition, the indentation problem of a multilayered nanoscale elastic medium under a rigid frictionless cylindrical punch is investigated to demonstrate the application of the proposed solution scheme.

关键词： functionally graded layer     Gurtin–Murdoch surface elasticity     multilayered medium     size dependency     stiffness matrix    

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标题 作者 时间 类型 操作

Study of simultaneous saccharification and fermentation for steam exploded wheat straw to ethanol

LUO Peng, YANG Chuanmin, LIU Zhong, WANG Gaosheng

期刊论文

Designer enzyme for green materials innovation: Lactate-polymerizing enzyme as a key catalyst

Seiichi Taguchi

期刊论文

Influence of glucose feeding on the ligninolytic enzyme production of the white-rot fungus Phanerochaete

ZHOU Xiaoyan, WEN Xianghua, FENG Yan

期刊论文

Diffusion process in enzyme–metal hybrid catalysts

期刊论文

Detection of Escherichia coli in wastewater based on enzyme immunoassay

XI Haiyan, CAI Qiang, HE Miao, SHI Hanchang

期刊论文

Enzyme@bismuth-ellagic acid: a versatile platform for enzyme immobilization with enhanced acid-base stability

期刊论文

Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

期刊论文

enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial loading

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

期刊论文

Cofactor engineering in cyanobacteria to overcome imbalance between NADPH and NADH: A mini review

Jongmoon Park,Yunnam Choi

期刊论文

Reconsideration on the effect of nitrogen on mixed culture polyhydroxyalkanoate production toward high organic loading

Zhiqiang Chen, Lizhi Zhao, Ye Ji, Qinxue Wen, Long Huang

期刊论文

Plant diversity reduces the effect of multiple heavy metal pollution on soil enzyme activities and microbial

Yang GAO, Chiyuan MIAO, Jun XIA, Liang MAO, Yafeng WANG, Pei ZHOU

期刊论文

Effect of loading rate on shear strength parameters of mechanically and biologically treated waste

期刊论文

Degradation of 4-aminophenol by hydrogen peroxide oxidation using enzyme from Serratia marcescens as

SUN Min, YOU Yahua, DENG Shengsong, GAO Wenxia, YAO Risheng

期刊论文

Microcystin-LR detection based on indirect competitive enzyme-linked immunosorbent assay

SHENG Jianwu, HE Miao, YU Shaoqing, SHI Hanchang, QIAN Yi

期刊论文

Axisymmetric loading on nanoscale multilayered media

期刊论文