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Insights into the changes of amino acids, microbial community, and enzymatic activities related with

《环境科学与工程前沿（英文）》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1635-y

摘要：

● The highest seed germination index was achieved at 0.3 g/g total solids of food waste.

关键词： Composting     Food waste     Amino acids     Microbial community     Enzymatic activity     Nutrient quality    

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USING AN AQUEOUS ENZYMATIC METHOD

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 623-634 doi: 10.15302/J-FASE -2021400

摘要：

Schizochytrium sp., a marine microalga, is a potential source of edible oil due to its short growth cycle and rapid lipid accumulation, especially of docosahexaenoic acid. An approach to isolate edible microalgal oil from Schizochytrium sp. using aqueous enzymatic extraction (AEE) was developed. Parameters were optimized by single-factor experiments followed by Box-Behnken design. Proteases were effective in extracting oil. The maximum free oil recovery (49.7%±0.58%) and total oil recovery (68.1%±0.94%) were obtained under optimum conditions of liquid-to-solid ratio of 4.8:1, a 2.5% enzyme concentration of papain and an extraction time of 2.2 h. There was a significant difference (P<0.05) in polyunsaturated fatty acid composition between microalgal oil obtained by AEE and by Soxhlet extraction, with the former having superior physiochemical properties and higher concentrations of bioactive components including total phenolic compounds and total tocopherols. These findings indicate a potential application of AEE for extraction of oil from Schizochytrium sp.

 

关键词： antioxidant activity / aqueous enzymatic extraction / edible microalgal oil / fatty acid composition / physicochemical properties    

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Production of pectic extracts from sugar beet pulp with antiproliferative activity on a breast cancer

Jacqueline CONCHA, Caroline WEINSTEIN, María Elvira Zú?IGA

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 482-489 doi: 10.1007/s11705-013-1342-5

摘要： In the last years, sugar beet pectins have been the subject of several investigations involving extraction methodologies, chemical composition and functional properties. The structure of pectins, which depends on the extraction method, is decisive in their capacity to induce apoptosis on several cancer cell lines like colon, prostate and breast. In this work, sugar beet pectin extraction was performed in the following steps: lipid extraction with hexane, removal of soluble complex carbohydrates and proteins, and enzymatic treatment with amyloglucosidase, protease, and pectinase. The enzymatic treatment was carried out with Rohapect DA6L under the following conditions: 50°C, pH 4.0, 2% enzyme/substrate (E/S) ratio, 15 h, and a solid to liquid ratio of 1 ∶ 10. The pectic extract showed a degree of polymerization (DP) profile of 55.8% with DP≥7; 4.9% with DP6; 5.8% between DP2 and DP6 ; 4.7% with DP2; and 28.8% with DP1. The pectic extract was examined for its antiproliferative activity on the MCF-7 breast cancer cell line. At a concentration range of 12.5–25 mg/mL the pectic extract killed 80.6% of the cells, exhibiting a higher antiproliferative activity than 4-hydroxytamoxifen (4-OHT), a classical anticancer drug, which killed 56.5% of the cells.

关键词： pectic extracts     antiproliferative activity     breast cancer     enzymatic treatment    

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Nitrogen-doped graphene approach to enhance the performance of a membraneless enzymatic biofuel cell

Alireza AHMADIAN YAZDI, Jie XU

《能源前沿（英文）》 2018年 第12卷 第2期   页码 233-238 doi: 10.1007/s11708-018-0529-3

摘要： Heteroatom-doping of pristine graphene is an effective route for tailoring new characteristics in terms of catalytic performance which opens up potentials for new applications in energy conversion and storage devices. Nitrogen-doped graphene (N-graphene), for instance, has shown excellent performance in many electrochemical systems involving oxygen reduction reaction (ORR), and more recently glucose oxidation. Owing to the excellent sensitivity of N-graphene, the development of highly sensitive and fast-response enzymatic biosensors is made possible. However, a question that needs to be addressed is whether or not improving the anodic response to glucose detection leads to a higher overall performance of enzymatic biofuel cell (eBFC). Thus, here we first synthesized N-graphene via a catalyst-free single-step thermal process, and made use of it as the biocatalyst support in a membraneless eBFC to identify its role in altering the performance characteristics. Our findings demonstrate that the electron accepting nitrogen sites in the graphene structure enhances the electron transfer efficiency between the mediator (redox polymer), redox active site of the enzymes, and electrode surface. Moreover, the best performance in terms of power output and current density of eBFCs was observed when the bioanode was modified with highly doped N-graphene.

关键词： enzymatic fuel cell     nitrogen-doped graphene     reduced graphene oxide     catalyst-free synthesis    

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Dissolution and enzymatic hydrolysis of casein micelles studied by dynamic light scattering

LIU Rui, QI Wei, SU Rongxin, ZHANG Yubin, JIN Fengmin, HE Zhimin

《化学科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 123-127 doi: 10.1007/s11705-007-0023-7

摘要： The effects of temperature, ionic strength, and enzymatic hydrolysis on the average hydrodynamic radius () of casein micelles in phosphate buffer were studied by using dynamic light scattering. The results showed that the average value of casein micelles decreased irreversibly during the heating, decreased with the increase of ionic strength in lower ionic strength solution (less than 0.05 mol/L), but opposite in higher ionic strength solution (above 0.1 mol/L). The value of casein increased rapidly during the process of enzymatic hydrolysis, and the structural model of casein micelles in the enzymatic hydrolysis process was also proposed, i.e. the casein micelle changed from compact sphere into unfolded and regularly flocky peptides.

关键词： compact     strength     temperature     regularly flocky     heating    

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Study on enzymatic hydrolysis of steam exploded straw by using shaking ball

SUN Zhanwei, FU Xiaoguo, CHEN Hongzhang, WANG Yanhui, MA Runyu

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 22-27 doi: 10.1007/s11705-008-0002-7

摘要： A novel method of enzymatic hydrolysis was developed in this paper to produce a high conversion yield and hydrolysis rate. A comparison was described by using three methods of enzymatic hydrolysis and adsorption of steam exploded straw (SEWS): shaking ball in the regime, shaking with stirrer bed, and static state. The most adequate filter-paper activity, speed and reaction time were 3.6 × 10 mol/(smL), 150 r/min and 24 h, respectively, with the reducing sugar yield of 0.43. The results showed that the method of shaking ball produced the highest adsorption, conversion yields and hydrolysis rate of the enzyme. This might be due to the continuous frequency increase of enzyme adsorption and desorption on the substrate surface as well as the relieved end-product inhibition. The morphological variation of SEWS was characterized by environmental scanning electron microscopy (ESEM).

关键词： adequate filter-paper     comparison     conversion     continuous frequency     substrate    

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Valorisation of protein waste: An enzymatic approach to make commodity chemicals? ?

Madura B. A. Kumar, Yuan Gao, Wei Shen, Lizhong He

《化学科学与工程前沿（英文）》 2015年 第9卷 第3期   页码 295-307 doi: 10.1007/s11705-015-1532-4

摘要： Protein-rich waste is an abundantly available resource that is currently used mainly as animal feed and fertilizers. Valorisation of protein waste to higher value products, particularly commodity chemicals such as precursors for polymers, has attracted significant research efforts. Enzyme-based approaches, being environmentally-friendly compared to their chemical counterparts, promise sustainable processes for conversion of protein waste to valuable chemicals. This review provides a general overview on valorisation of protein waste and then further summarises the use of enzymes in different stages of the valorisation process—protein extraction and hydrolysis, separation of individual amino acids and their ultimate conversion into chemicals. Case studies of enzymatic conversion are presented for different amino acids including glutamic acid, lysine, phenylalanine, tyrosine, arginine and aspartic acid. The review compares the different enzyme reactors and operation modes for amino acid conversion. The emerging opportunities and challenges in the field are discussed: engineering powerful enzymes and integrating innovative processes for industrial application at a low cost.

关键词： amino acids     protein waste     reactor     conversion     commodity chemicals     enzymes    

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Enhanced enzymatic removal of anthracene by the mangrove soil-derived fungus,

Paul Olusegun Bankole, Kirk Taylor Semple, Byong-Hun Jeon, Sanjay Prabhu Govindwar

《环境科学与工程前沿（英文）》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1292-3

摘要： Abstract • A. sydowii strain bpo1 exhibited 99.8% anthracene degradation efficiency. • Four unique metabolic products were obtained after anthracene degradation. • Ligninolytic enzymes induction played vital roles in the removal of anthracene. • Laccase played a crucial role in comparison with other enzymes induced. The present study investigated the efficiency of Aspergillus sydowii strain bpo1 (GenBank Accession Number: MK373021) in the removal of anthracene (100 mg/L). Optimal degradation efficiency (98.7%) was observed at neutral pH, temperature (30℃), biomass weight (2 g) and salinity (0.2% w/v) within 72 h. The enzyme analyses revealed 131%, 107%, and 89% induction in laccase, lignin peroxidase, and manganese peroxidase respectively during anthracene degradation. Furthermore, the degradation efficiency (99.8%) and enzyme induction were significantly enhanced with the addition of 100 mg/L of citric acid and glucose to the culture. At varying anthracene concentrations (100–500 mg/L), the degradation rate constants (k1) peaked with increasing concentration of anthracene while the half-life (t1/2) decreases with increase in anthracene concentration. Goodness of fit (R2 = 0.976 and 0.982) was observed when the experimental data were subjected to Langmuir and Temkin models respectively which affirmed the monolayer and heterogeneous nature exhibited by A. sydwoii cells during degradation. Four distinct metabolites; anthracene-1,8,9 (2H,8aH,9aH)-trione, 2,4a-dihydronaphthalene-1,5-dione, 1,3,3a,7a-tetrahydro-2-benzofuran-4,7-dione and 2-hydroxybenzoic acid was obtained through Gas Chromatography-Mass spectrometry (GC-MS). A. sydowii exhibited promising potentials in the removal of PAHs.

关键词： Aspergillus sydowii     Anthracene     Biodegradation     Polycyclic aromatic hydrocarbons    

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IDEEA activity monitor: validity of activity recognition for lying, reclining, sitting and standing

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 126-131 doi: 10.1007/s11684-012-0236-0

摘要：

Recent evidence demonstrates the independent negative effects of sedentary behavior on health, but there are few objective measures of sedentary behavior. Most instruments measure physical activity and are not validated as measures of sedentary behavior. The purpose of this study was to evaluate the validity of the IDEEA system’s measures of sedentary and low-intensity physical activities: lying, reclining, sitting and standing. Thirty subjects, 14 men and 16 women, aged 23 to 77 years, body mass index (BMI) between 18 to 34 kg/m2, participated in the study. IDEEA measures were compared to direct observation for 27 activities: 10 lying in bed, 3 lying on a sofa, 1 reclining in a lawn chair, 10 sitting and 3 standing. Two measures are reported, the percentage of activities accurately identified and the percentage of monitored time that was accurately labeled by the IDEEA system for all subjects. A total of 91.6% of all observed activities were accurately identified and 92.4% of the total monitored time was accurately labeled. The IDEEA system did not accurately differentiate between lying and reclining so the two activities were combined for calculating accuracy. Using this approach the IDEEA system accurately identified 96% of sitting activities for a total of 97% of the monitored sitting time, 99% and 99% for standing, 87% and 88% for lying in bed, 87% and 88% for lying on the sofa, and 83% and 83% for reclining on a lawn chair. We conclude that the IDEEA system accurately recognizes sitting and standing positions, but it is less accurate in identifying lying and reclining positions. We recommend combining the lying and reclining activities to improve accuracy. The IDEEA system enables researchers to monitor lying, reclining, sitting and standing with a reasonable level of accuracy and has the potential to advance the science of sedentary behaviors and low-intensity physical activities.

关键词： IDEEA     activity monitor     sedentary behavior    

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Low intensity ultrasound stimulates biological activity of aerobic activated sludge

LIU Hong, YAN Yixin, WANG Wenyan, YU Yongyong

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 67-72 doi: 10.1007/s11783-007-0013-5

摘要： This work aims to explore a procedure to improve biological wastewater treatment efficiency using low intensity ultrasound. The aerobic activated sludge from a municipal wastewater treatment plant was used as the experimental material. Oxygen uptake rate (OUR) of the activated sludge (AS) was determined to indicate the changes of AS activity stimulated by ultrasound at 35 kHz for 0 40 min with ultrasonic intensities of 0 1.2 W/cm. The highest OUR was observed at the ultrasonic intensity of 0.3 W/cm and an irradiation period of 10 min; more than 15% increase was achieved immediately after sonication. More significantly, the AS activity stimulated by ultrasound could last 24 h after sonication, and the AS activity achieved its peak value within 8 h after sonication, or nearly 100% higher than the initial level after sonication. Therefore, to improve the wastewater treatment efficiency of bioreactors, ultrasound with an intensity of 0.3 W/cm could be employed to irradiate a part of the AS in the bioreactor for 10 min every 8 h.

关键词： sonication     irradiation     kHz     treatment efficiency     AS activity    

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preparation of Ag@AgCl/Bio-veins composites and their photocatalytic activity and recyclability

《化学科学与工程前沿（英文）》 2023年 第17卷 第7期   页码 906-917 doi: 10.1007/s11705-022-2273-9

摘要： The industrial application of nano-photocatalysts in wastewater treatment has been severely restricted for a long time due to their difficult separation, poor reusability, and low efficiency. In this work, a facile strategy was proposed to enhance the photocatalytic activity and recovery performance of Ag@AgCl nanocatalysts. Biological veins (Bio-veins) with a unique 3D porous construction were used as carriers for the in-situ growth of Ag@AgCl nanoparticles. Scanning electron microscopy results showed that the Ag@AgCl nanoparticles were uniformly loaded on the surface and interior of the Bio-veins, and the size of the Ag@AgCl nanoparticles immobilized on the Bio-veins (50–300 nm) was significantly smaller than Ag@AgCl obtained by the co-precipitation method (1–3 μm). The Bio-veins played a vital role in the photocatalysis reaction system. The degradation efficiency of the Ag@AgCl/Bio-veins(CI4) was up to 3.50 times as high as pure Ag@AgCl. Furthermore, the composites also exhibited excellent recyclability and stability under both visible and solar light. This work provided a suitable strategy for nano-photocatalysts for practical application and may also offer new possibilities for the high-value utilization of biomass materials.

关键词： Ag@AgCl     biological veins     photocatalytic activity     recyclability    

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Effect of 2-butenal manufacture wastewater to methanogenic activity and microbial community

Guangqing Song, Hongbo Xi, Xiumei Sun, Yudong Song, Yuexi Zhou

《环境科学与工程前沿（英文）》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1056-5

摘要：

The inhibition ratio sharply increased with the increasing COD.

The absorbance of UV-vis at 420 nm showed a linear correlation with the SMA.

The molecular structure of EPS has changed when COD was 9585 mg/L.

Illumina Miseq sequencing was employed to reveal the microbial composition.

关键词： 2-butenal manufacture wastewater     Methanogenic activity     Specific methanogenic activity (SMA)     Extracellular polymeric substance (EPS)     Microbial community    

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Antithrombin deficiency and decreased protein C activity in a young man with venous thromboembolism:

null

《医学前沿（英文）》 2018年 第12卷 第3期   页码 319-323 doi: 10.1007/s11684-017-0553-4

摘要：

Antithrombin and protein C are two crucial members in the anticoagulant system and play important roles in hemostasis. Mutations in and lead to deficiency or dysfunction of the two proteins, which could result in venous thromboembolism (VTE). Here, we report a Chinese 22-year-old young man who developed recurrent and serious VTE in cerebral veins, visceral veins, and deep veins of the lower extremity. Laboratory tests and direct sequencing of and were conducted for the patient and his family members. Coagulation tests revealed that the patient presented type I antithrombin deficiency combined with decreased protein C activity resulting from a small insertion mutation c.848_849insGATGT in and a short deletion variant c.572_574delAGA in . This combination of the two mutations was absent in 400 healthy subjects each from southern and northern China. Then, we summarized all the mutations of the and gene reported in the Chinese Han population. This study demonstrates that the combination of antithrombin deficiency and decreased protein C activity can result in severe VTE and that the coexistence of different genetic factors may increase the risk of VTE.

关键词： antithrombin deficiency     protein C activity     mutation     variant     venous thromboembolism     anticoagulants    

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A survey of physical activity among urban women in China

Shilin DENG MD, Tongyuan LIU,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 463-469 doi: 10.1007/s11684-009-0081-y

摘要： Few studies have been conducted to assess the level of physical activity (PA) of women in China. The purpose of this study was to describe the prevalence of PA among women in Wuhan and explore sociodemographic and behavioral correlation to PA for the population. A total of 1359 community-dwelling women (42.9713.60 years old) participated in this study. The long-version IPAQ was used to define the level of PA. 45.7% of women were considered physically active, and 27.5% were vigorously active. The proportion of physical inactivity was around 26.8%. The total and 4 domains of PA showed significant age, education level, and occupation variation. PA tended to be lower as the age declined. PA in transportation, housework, leisure time, and the total tended to be the lowest or the second lowest among the women aged 18–35 years old. PA tended to be lower as the level of education increased. Among the 5 indices, PAwas the lowest among women with college education, especially those with postgraduate education. PA tended to be the lowest among the women of office staff and instructor or technician. Generally, the total and 4 domains of PA showed significant age, education level, and occupation variation. Physical inactivity appears to be more common among younger women, or college-educated women, office ladies, and female instructor and technicians.

关键词： physical activity     urban women     China    

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Probing the catalytic activity of M-N

Fan Ge, Qingan Qiao, Xin Chen, You Wu

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1206-1216 doi: 10.1007/s11705-020-2017-7

摘要： In this work, the detailed oxygen reduction reaction (ORR) catalytic performance of M-N O (M= Fe, Co, and Ni; = 1–4) has been explored via the detailed density functional theory method. The results suggest that the formation energy of M-N O shows a good linear relationship with the number of doped O atoms. The adsorption manner of O on M-N O changed from end-on ( = 1 and 2) to side-on ( = 3 and 4), and the adsorption strength gradually increased. Based on the results for binding strength of ORR intermediates and the Gibbs free energy of ORR steps on the studied catalysts, we screened out two highly active ORR catalysts, namely Co-N O and Ni-N O , which possess very small overpotentials of 0.27 and 0.32 V, respectively. Such activities are higher than the precious Pt catalyst. Electronic structure analysis reveals one of the reasons for the higher activity of Co-N O and Ni-N O is that they have small energy gaps and moderate highest occupied molecular orbital energy levels. Furthermore, the results of the density of states reveal that the O doping can improve the electronic structure of the original catalyst to tune the adsorption of the ORR intermediates.

关键词： M-N-C catalyst     oxygen doping     oxygen reduction reaction     catalytic activity     density functional theory    

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标题 作者 时间 类型 操作

Insights into the changes of amino acids, microbial community, and enzymatic activities related with

期刊论文

USING AN AQUEOUS ENZYMATIC METHOD

期刊论文

Production of pectic extracts from sugar beet pulp with antiproliferative activity on a breast cancer

Jacqueline CONCHA, Caroline WEINSTEIN, María Elvira Zú?IGA

期刊论文

Nitrogen-doped graphene approach to enhance the performance of a membraneless enzymatic biofuel cell

Alireza AHMADIAN YAZDI, Jie XU

期刊论文

Dissolution and enzymatic hydrolysis of casein micelles studied by dynamic light scattering

LIU Rui, QI Wei, SU Rongxin, ZHANG Yubin, JIN Fengmin, HE Zhimin

期刊论文

Study on enzymatic hydrolysis of steam exploded straw by using shaking ball

SUN Zhanwei, FU Xiaoguo, CHEN Hongzhang, WANG Yanhui, MA Runyu

期刊论文

Valorisation of protein waste: An enzymatic approach to make commodity chemicals? ?

Madura B. A. Kumar, Yuan Gao, Wei Shen, Lizhong He

期刊论文

Enhanced enzymatic removal of anthracene by the mangrove soil-derived fungus,

Paul Olusegun Bankole, Kirk Taylor Semple, Byong-Hun Jeon, Sanjay Prabhu Govindwar

期刊论文

IDEEA activity monitor: validity of activity recognition for lying, reclining, sitting and standing

null

期刊论文

Low intensity ultrasound stimulates biological activity of aerobic activated sludge

LIU Hong, YAN Yixin, WANG Wenyan, YU Yongyong

期刊论文

preparation of Ag@AgCl/Bio-veins composites and their photocatalytic activity and recyclability

期刊论文

Effect of 2-butenal manufacture wastewater to methanogenic activity and microbial community

Guangqing Song, Hongbo Xi, Xiumei Sun, Yudong Song, Yuexi Zhou

期刊论文

Antithrombin deficiency and decreased protein C activity in a young man with venous thromboembolism:

null

期刊论文

A survey of physical activity among urban women in China

Shilin DENG MD, Tongyuan LIU,

期刊论文

Probing the catalytic activity of M-N

Fan Ge, Qingan Qiao, Xin Chen, You Wu

期刊论文