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Biosorption of mercury and lead by aqueous

Pratibha SANJENBAM, Kumar SAURAV, Krishnan KANNABIRAN

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 198-202 doi: 10.1007/s11705-012-1285-2

摘要： Toxic heavy metals are increasingly accumulating in the environment worldwide and are considered to be life threatening contaminants. The biosorption of mercury and lead by marine actinomycetes isolated from marine sediment collected from the Bay of Bengal coast of Puducherry, India, was evaluated. The maximum tolerance concentration (MTC) of sp. was determined by a well diffusion method and a broth dilution method. The effects of the initial metal ion concentration, the pH and the biomass dosage on the biosorption of mercury and lead ions were investigated. The MTC of the isolate to metals was 200 mg·L for mercury and 1800 mg·L for lead. At neutral pH, the isolate had a maximum biosorption of metal ions of 200 mg·L and 150 mg·L for mercury and lead respectively. Fourier transform infrared (FTIR) absorption spectra showed the chemical interactions between the functional groups in the biomass such as hydroxyl (-OH), amine (-NH ), carboxyl (-COOH) and the metal ions. The isolate was further characterized by molecular taxonomy and identified as a member of the genus Based on the phenotypic and phylogenetic analysis, the strain was classified as a new species of the genus and designated as VITSVK9 sp. (HM137310). A blast search of the 16S rDNA sequence of the strain showed the most similarity (95%) with sp. A515 Ydz-FQ (EU384279). Based on the results, it can be concluded that this marine could be used as a biosorbent for the removal of heavy metal ions from aqueous environments.

关键词： mercury     lead     biosorption     maximum tolerance concentration     Streptomyces VITSVK9 sp.    

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Application of statistical design for the production of inulinase by

M. DILIPKUMAR, M. RAJASIMMAN, N. RAJAMOHAN

《化学科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 463-470 doi: 10.1007/s11705-011-1112-1

摘要： A Plackett-Burman design was employed for screening 18 nutrient components for the production of inulinase using sp. and pressmud as the substrate via solid-state fermentation (SSF). From the experiments, three nutrients viz. yeast extract, FeSO ·7H O, and NH NO were found to be the most significant components. Hence these three components were selected and optimized using Response Surface Methodology (RSM). The optimum conditions are: yeast extract 0.00274 g/gds, FeSO ·7H O 0.00011 g/gds and NH NO 0.00772 g/gds. The effect of the substrate concentration and initial moisture content were also studied. A substrate concentration of 12 g and an initial moisture content of 65% are optimum for the maximum production of inulinase (89 U/gds).

关键词： inulinase     pressmud     Response Surface Methodology (RSM)     streptomyces sp    

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In situ enhanced bioremediation of dichlorvos by a phyllosphere

Jiying NING, Gang GANG, Zhihui BAI, Qing HU, Hongyan QI, Anzhou MA, Xuliang ZHUAN, Guoqiang ZHUANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 231-237 doi: 10.1007/s11783-011-0316-4

摘要： A bacterium capable of degrading dichlorvos was isolated from the rape phyllosphere and designated YD4. The strain was identified as sp., based on its phenotypic features and 16S rRNA gene sequence. Strain YD4 was able to utilize dichlorvos as the sole source of phosphorus. enhanced bioremediation of dichlorvos by YD4 was hereafter studied. Chlorpyrifos and phoxim could also be degraded by this strain as the sole phosphorus source. A higher degradation rate of dichlorvos was observed after spraying YD4 onto the surface of rape leaves when compared to the sterilized-YD4 and water-treated samples. The results indicated that pesticide-degrading epiphytic bacterium could become a new way for phyllosphere bioremediation where the hostile niche is unsuitable for other pesticide-degrading bacteria isolated from soil and water.

关键词： enhanced bioremediation     organophosphorus pesticides     phyllosphere     Flavobacterium sp.    

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Carbon dioxide fixation by

Xuan JIA, Hai YAN, Zijing WANG, Huanju HE, Qianqian XU, Haiou WANG, Chunhua YIN, Liqin LIU

《环境科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 402-408 doi: 10.1007/s11783-010-0223-0

摘要： A promising microalgal strain isolated from fresh water, which can grow both autotrophically on inorganic carbon under lighting and heterotrophically on organic carbon without lighting, was identified as sp. USTB-01 with the phylogenetic analysis based on 18S ribosomal ribonucleic acid (rRNA) gene sequences. In the heterotrophic batch culture, more than 20.0 g·L of cell dry weight concentration (DWC) of sp. USTB-01 was obtained at day 5, and which was used directly to seed the autotrophic culture. A novel fermentor-helical combined photobioreactor was established and used to cultivate sp. USTB-01 for the fixation of carbon dioxide (CO ). It showed that the autotrophic growth of sp. USTB-01 in the combined photobioreactor was more effective than that in the fermentor alone and the maximum DWC of 2.5 g·L was obtained at day 6. The highest CO fixation of 95% appeared on day 1 in the exponential growth phases of sp. USTB-01 and 49.8% protein was found in the harvested microalgal cells.

关键词： Chlorella sp. USTB-01     carbon dioxide fixation     combined photobioreactor    

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Mutagenesis and selective breeding of a high producing

Tian WANG, Shiru JIA, Zhilei TAN, Yujie DAI, Shuai SONG, Guoliang WANG

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 179-183 doi: 10.1007/s11705-012-1273-6

摘要： -Poly- -lysine ( -PL) is an -lysine linear homopolymer, which is produced by bacteria belonging to the family and by ergot fungi. However, the production of -PL by the wild bacteria strain is very low, which limits its utilization. In most bacteria including the genus, -lysine is a precursor of -PL and is biosynthesized by the -aspartate pathway. Aspartokinase (Ask) is the first key enzyme in this pathway and is subject to complex regulation such as the feedback inhibition by the end product amino acids. In addition, phosphoenolpyruvate carboxykinase is feedback-regulated by -aspartate. To reduce these feedback inhibitions and to improve -PL productivity, resistant mutants were produced using sulfaguanidine (SG) + glycine+ -lysine+ -3-hydroxynorvaline (AHV) as selective markers. Using the interaction between -PL and the charged dye in the solid culture medium, hundreds of colonies were simultaneously screened in a quick and effective manner. Finally, one -PL-producing strain, L9, was selected. The productivity of this strain during flask fermentation was 0.77 g/L, which was 15% higher than that of the original strain. Moreover, its fermentation performance and genetic characteristics were very stable.

关键词： ?-poly-L-lysine     plasma     AHV     Streptomyces diastatochromogenes     fermentation    

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EXTRACTION AND EVALUATION OF EDIBLE OIL FROM SCHIZOCHYTRIUM SP. 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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Microcystin-LR biodegradation by

Chengbin XIAO, Hai YAN, Junfeng WANG, Wei WEI, Jun NING, Gang PAN

《环境科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 526-532 doi: 10.1007/s11783-010-0261-7

摘要： A promising bacterial strain for biodegrading microcystin-LR (MC-LR) as the sole carbon and nitrogen source was successfully isolated from Lake Dianchi, China. The strain was identified as sp. USTB-05, which was the first isolated MCs-biodegrading sp. in China. The average biodegradation rate of MC-LR by sp. USTB-05 was 28.8 mg·L per day, which was apparently higher than those of other bacteria reported so far. The optimal temperature and pH for both strain USTB-05 growth and MC-LR biodegradation were 30°C and 7.0, respectively. The release of MC-LR from the cyanobacterial cells collected from Lake Guishui and the biodegradation of MC-LR by both strain and cell-free extract (CE) were investigated. The results indicated that MC-LR with the initial concentration of 4.0 mg·L in water was biodegraded by sp. USTB-05 within 4 d, while MC-LR with the initial concentration of 28.8 mg·L could be completely removed in 3 h by CE of sp. USTB-05 containing 350 mg·L protein. During enzymatic biodegradation of MC-LR, two intermediate metabolites and a dead-end product were observed on an HPLC chromatogram. Moreover, the similar scanning profiles of MC-LR and its metabolic products indicate that the Adda side-chain of MC-LR was kept intact in all products.

关键词： microcystin-LR(MC-LR)     biodegradation     Sphingopyxis sp     USTB-05     cell-free extract    

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The <italic>rpoSitalic> deficiency suppresses acetate accumulation in glucose-enriched culture of <italic>Escherichia coliitalic> under an aerobic condition

Prayoga SURYADARMA, Yoshihiro OJIMA, Yuto FUKUDA, Naohiro AKAMATSU, Masahito TAYA

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 152-157 doi: 10.1007/s11705-012-1287-0

摘要： The role of on the central carbon metabolism was investigated through analyzing the deficiency of this regulon gene under aerobic and glucose-enriched culture conditions. The experimental results showed that while the wild type cells exhibited an overflow metabolism effect, the -deleting mutation alleviated this effect with the significant suppression of acetate accumulation under a high glucose condition. This gene deletion also induced the twofold upregulation of and one-tenth downregulation of , respectively. The overflow metabolism effect was confirmed to be recovered by re-introducing gene into the mutant. These results demonstrated changed the central carbon metabolism toward acetate overflow through dehydrogenation of pyruvate and reduction of TCA cycle activity.

关键词： Escherichia coli     rpoS     aerobic and glucose-enriched culture     overflow metabolism    

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Nitrogen distribution in the products from the hydrothermal liquefaction of sp. and sp.

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 985-995 doi: 10.1007/s11705-021-2126-y

摘要： The high contents of nitrogen-containing organic compounds in biocrude obtained from hydrothermal liquefaction of microalgae are one of the most concerned issues on the applications and environment. In the project, Chlorella sp. and Spirulina sp. were selected as raw materials to investigate the influence of different reaction conditions (i.e., reaction temperature, residence time, solid loading rate) on the distribution of nitrogen in the oil phase and aqueous phase. Three main forms of nitrogen-containing organic compounds including nitrogen-heterocyclic compounds, amide, and amine were detected in biocrudes. The contents of nitrogen-heterocyclic compounds decreased with temperature while amide kept increasing. The effect of residence time on the components of nitrogen-containing organic compounds was similar with that of temperature. However, the influence of solid loading rate was insignificant. Moreover, it was also found that the differences of amino acids in the protein components in the two microalgae might affect the nitrogen distribution in products. For example, nitrogen in basic amino acids of Spirulina sp. preferred to go into the aqueous phase comparing with the nitrogen in neutral amino acids of Chlorella sp. In summary, a brief reaction map was proposed to describe the nitrogen pathway during microalgae hydrothermal liquefaction.

关键词： microalgae     hydrothermal liquefaction     biocrude     nitrogen distribution    

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Effect of pH on biologic degradation of

Hongjing LI, Mengli HAO, Jingxian LIU, Chen CHEN, Zhengqiu FAN, Xiangrong WANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 224-230 doi: 10.1007/s11783-011-0314-6

摘要： In this paper, the effect of pH on biological degradation of by alga-lysing bacteria in laboratory-scale sequencing batch biofilm reactors (SBBRs) was investigated. After 10 d filming with waste activated sludge, the biological film could be formed, and the bioreactors in which laid polyolefin resin filler were used to treat algal culture. By comparing the removal efficiency of chlorophyll at different aerobic time, the optimum time was determined as 5 h. Under pH 6.5, 7.5, and 8.5 conditions, the removal rates of were respectively 75.9%, 83.6%, and 78.3% (in term of chlorophyll ), and that of Chemical Oxygen Demand (COD ) were 30.6%, 35.8%, and 33.5%. While the removal efficiencies of ammonia nitrogen ( ) were all 100%. It was observed that the sequence of the removal efficiencies of algae, and organic matter were pH 7.5>pH 8.5>pH 6.5. The results showed that the dominant alga-lysing bacteria in the SBBRs was strain HM-01, which was identified as sp. by Polymerase Chain Reaction (PCR) amplification of the 16S rRNA gene, Basic Local Alignment Search Tool (BLAST) analysis, and comparison with sequences in the GenBank nucleotide database. The algicidal activated substance which HM-01 strain excreted could withstand high temperature and pressure, also had better hydrophily and stronger polarity.

关键词： pH     biological degradation     alga-lysing bacteria     sequencing batch biofilm reactor (SBBR)     16S rRNA     Bacillus sp    

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Synthesis of depsipeptides from

Hongfei CAO, Yakai FENG, Heyun WANG, Li ZHANG, Musammir KHAN, Jintang GUO

《化学科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 409-415 doi: 10.1007/s11705-011-1141-9

摘要： By using the corresponding -amino acid sodium as initiator, -caprolactone-depsipeptides CL-Ala and CL-Leu were prepared by the reactions of -caprolactone (CL) with -alanine and -leucine, respectively, and -dioxanone-depsipeptide (PDO-Leu) was prepared by the reaction of -dioxanone (PDO) with -leucine. Two poly( -caprolactone) oligomers (PCL-Ala and PCL-Leu) of different molecular weights with depsipeptide unit were synthesized by controlling the feed ratio of -amino acid sodium and CL. The presence of the depsipeptide structure in these obtained products was confirmed by H NMR spectra and the molecular weight of the poly( -caprolactone) oligomers was measured by gel permeation chromatography (GPC). These products contain a hydroxyl group and a carboxyl group in one molecule, which means they could act as bifunctional monomers for further polymerization to prepare high molecular weight polymers. By this way, the depsipeptide unit could be introduced into the polymers and the biodegradation rates of the novel polymers could be well controlled in vivo by the tailored molecular structures.

关键词： ?-caprolactone     p-dioxanone     L-alanine     L-leucine     depsipeptide    

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Assessment of toxicity of two nitroaromatic compounds in the freshwater fish

Hongyan SHEN, Jixi GAO, Jinsheng WANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 518-523 doi: 10.1007/s11783-012-0427-6

摘要： This study was conducted to evaluate the toxicological response of -nitrotoluene and -nitroaniline to the key fish species, . A freshwater fish bioassay based on the 96 h was used to estimate the single and joint toxicity of the two chemicals. The toxicity of -nitrotoluene was greater than that of -nitroaniline based on 96 h values of 40.74 mg·L and 48.99 mg·L , respectively. Both compounds had moderate toxicity toward , and this toxicity increased with the exposure duration and concentration. Binary mixtures of the compounds were more toxic than the individual compounds at 96 h, and they acted upon partial addition. When the exposure time was longer, the toxicity increased for mixtures of compounds with the same concentration or toxicity. The results of this study suggest that exposure to a combination of these chemicals would result in a higher environmental risk in aquatic systems than exposure to either compound alone. Further research is needed to investigate the combined effects and sublethal toxicity of -nitrotoluene and -nitroaniline, since they are both still used in China.

关键词： joint toxicity     Cyprinus carpio     LC50     p-nitrotoluene     p-nitroaniline     toxic unit    

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Investigations on color variations of <italic>Morpho rhetenoritalic> butterfly wing scales

Guanglan LIAO, Haibo ZUO, Xuan JIANG, Xuefeng YANG, Tielin SHI

《机械工程前沿（英文）》 2012年 第7卷 第4期   页码 394-400 doi: 10.1007/s11465-012-0347-y

摘要：

Experiments and simulations are carried out to investigate the optical properties of butterfly wing scales. The upper surface of a male butterfly wing presents a single-layer of scales, the microstructures of which are responsible for the brilliant blue color. The color varies from cyan blue to yellow green and soon afterwards returns back to cyan blue when some ethanol is dropped on the upper surface. At the start of the ethanol volatilization process, the reflection spectrum remains stable. As the ethanol further volatilizes, the peak reflectance decreases slightly, then increases dramatically. Meanwhile, the peak wavelength keeps approximately constant, then decreases, and keeps almost stable at the end of the process. Therefore, the optical properties depend strongly on the varying ambient conditions, including the refractive index and the thickness of the packing medium. Moreover, the possible causes for the scales in dark green region after several dropping ethanol experiments are clarified. This research benefits our understanding of the color variation mechanisms of the wing scales, and provides inspiration for further studies and applications.

关键词： Morpho rhetenor     microstructures     color variations     ambient medium    

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Administration with

Qi RUI, Qin LU, Dayong WANG

《医学前沿（英文）》 2009年 第3卷 第1期   页码 76-90 doi: 10.1007/s11684-009-0002-0

摘要： During normal metabolism, oxidative byproducts will inevitably generate and damage molecules thereby impairing their biological functions, including the aging process. (补肾抗衰方, ) is a traditional Chinese medicine widely used for clinically treating premature ovarian failure. In the present study, administration at high concentrations significantly increased lifespan, slowed aging-related decline, and delayed accumulation of aging-related cellular damage in wild-type . administration could further largely alleviate the aging defects induced by UV and oxidative stresses, and administration at different concentrations could largely rescue the aging defects in mutant animals. The protective effects of administration on aging process were at least partially dependent on the Ins/IGF-like signaling pathway. Moreover, administration at different concentrations obviously altered the expression patterns of antioxidant genes and suppressed the severe stress responses induced by UV and oxidative stresses, suggesting that -induced tolerance to UV or oxidative stress might result from reactive oxygen species scavenging. administration during development was not necessarily a requirement for UV and oxidative stress resistance, and the concentrations of administrated examined were not toxic for nematodes. Therefore, administration could effectively retrieve the aging defects induced by UV irradiation and oxidative stress in .

关键词： Bushenkangshuai Tang     UV irradiation     oxidative stress     tissue senescence     lifespan     Caenorhabditis elegans    

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Biosorption of Cd

Fengyu ZAN, Shouliang HUO, Beidou XI, Xiulan ZHAO

《环境科学与工程前沿（英文）》 2012年 第6卷 第1期   页码 51-58 doi: 10.1007/s11783-011-0206-9

摘要： The biosorption of Cd and Cu onto the immobilized ( ) was investigated in this study. Adsorption kinetics, isotherms and the effect of pH were studied. The results indicated that the biosorption of Cd and Cu on the immobilized was fast at initial stage and then became slow. The maximum biosorption of heavy metal ions on immobilized were observed at pH 4 for Cd and Cu . by the pseudo-second-order model described the sorption kinetic data well according to the high correlation coefficient ( ) obtained. The biosorption isotherm was fitted well by the Langmuir model, indicating possible mono-layer biosorption of Cd and Cu on the immobilized . Moreover, the immobilized after the sorption of Cd and Cu could be regenerated and reused.

关键词： Saccharomyces cerevisiae (S. cerevisiae)     biosorption     heavy metals     immobilization     desorption    

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标题 作者 时间 类型 操作

Biosorption of mercury and lead by aqueous

Pratibha SANJENBAM, Kumar SAURAV, Krishnan KANNABIRAN

期刊论文

Application of statistical design for the production of inulinase by

M. DILIPKUMAR, M. RAJASIMMAN, N. RAJAMOHAN

期刊论文

In situ enhanced bioremediation of dichlorvos by a phyllosphere

Jiying NING, Gang GANG, Zhihui BAI, Qing HU, Hongyan QI, Anzhou MA, Xuliang ZHUAN, Guoqiang ZHUANG

期刊论文

Carbon dioxide fixation by

Xuan JIA, Hai YAN, Zijing WANG, Huanju HE, Qianqian XU, Haiou WANG, Chunhua YIN, Liqin LIU

期刊论文

Mutagenesis and selective breeding of a high producing

Tian WANG, Shiru JIA, Zhilei TAN, Yujie DAI, Shuai SONG, Guoliang WANG

期刊论文

EXTRACTION AND EVALUATION OF EDIBLE OIL FROM SCHIZOCHYTRIUM SP. USING AN AQUEOUS ENZYMATIC METHOD

期刊论文

Microcystin-LR biodegradation by

Chengbin XIAO, Hai YAN, Junfeng WANG, Wei WEI, Jun NING, Gang PAN

期刊论文

The <italic>rpoSitalic> deficiency suppresses acetate accumulation in glucose-enriched culture of <italic>Escherichia coliitalic> under an aerobic condition

Prayoga SURYADARMA, Yoshihiro OJIMA, Yuto FUKUDA, Naohiro AKAMATSU, Masahito TAYA

期刊论文

Nitrogen distribution in the products from the hydrothermal liquefaction of sp. and sp.

期刊论文

Effect of pH on biologic degradation of

Hongjing LI, Mengli HAO, Jingxian LIU, Chen CHEN, Zhengqiu FAN, Xiangrong WANG

期刊论文

Synthesis of depsipeptides from

Hongfei CAO, Yakai FENG, Heyun WANG, Li ZHANG, Musammir KHAN, Jintang GUO

期刊论文

Assessment of toxicity of two nitroaromatic compounds in the freshwater fish

Hongyan SHEN, Jixi GAO, Jinsheng WANG

期刊论文

Investigations on color variations of <italic>Morpho rhetenoritalic> butterfly wing scales

Guanglan LIAO, Haibo ZUO, Xuan JIANG, Xuefeng YANG, Tielin SHI

期刊论文

Administration with

Qi RUI, Qin LU, Dayong WANG

期刊论文

Biosorption of Cd

Fengyu ZAN, Shouliang HUO, Beidou XI, Xiulan ZHAO

期刊论文