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Screening of potential aquatic probiotics from the major microflora of guppies (

Aparna BALAKRISHNA, T. R. KEERTHI

《化学科学与工程前沿(英文)》 2012年 第6卷 第2期   页码 163-173 doi: 10.1007/s11705-012-1283-4

摘要: The fish ( ) was used as the source for probiotics. 46 bacterial isolates were obtained from the skin, gills, guts and intestines of the guppy, (collected from a government model fish farm in Kottayam, India). Of the above isolated strains, four isolates were selected based on their inhibitory spectrum against five indicator strains, 1739, 3906, 2495, 1271 and 1424 (standard cultures collected from Microbial Type Culture Collection (MTCC) Chandigarh, India). Among the resulting isolates, two were gram-positive cocci, namely MBTU-PB2 and MBTU-PB3 and belong to the genus . The other two were gram-negative rods, namely MBTU-PB1 and MBTU-PB4, of the genera and , respectively. The basic probiotic characteristics of these isolates such as the production of bacteriocin like inhibitory substances (BLIS), antibiotic sensitivities and growth profiles were also determined. The above four isolated strains exhibited different antagonisms than the five indicator strains. During incubation, the antibacterial activity gradually increased in the inhibition zone and was influenced by the lag period ( ) and doubling time. The lag periods for most of the four selected strains were shorter than those of the indicator strains and the isolates had different growth rates ( ) than the indicator strains. All four isolates produced BLIS, however, the strains had different BLIS activities against the indicator strains. Treatment of the neutralized cell free supernatants of the selected isolates with proteases eliminated or reduced the BLIS activity, suggesting a proteinaceous nature of the inhibitory compounds. Further, the optimum BLIS activity was observed at neutral pH after 18 h of incubation. The antibiotic sensitivity assay revealed that the isolates were susceptible to routinely used antibiotics, whereas the plasmid profiles showed that the plasmids had no role in the antagonistic properties of the four isolated strains. The results showed that the isolates could be a promising source for biocontrol agents in aquacultures.

关键词: aquaculture     normal flora     immunomodulatory effect     probiotic     antagonistic principle     bacteriocin like inhibitory substances    

Effects of oxidizing environment on digestate humification and identification of substances governing

《环境科学与工程前沿(英文)》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1520-0

摘要:

• Liquid digestate humification was investigated under different oxidizing environment.

关键词: Liquid digestate     MnO2     Oxygen     DOM transformation     Humic-like acids    

Interaction and combined toxicity of microplastics and per- and polyfluoroalkyl substances in aquatic

《环境科学与工程前沿(英文)》 2022年 第16卷 第10期 doi: 10.1007/s11783-022-1571-2

摘要:

● Adsorption of PFASs on MPs and its mechanisms are critically reviewed.

关键词: Microplastics     Per- and Polyfluoroalkyl substances     Adsorption     Transport     Transformation    

Effects of phosphatidylinositol 3-kinase inhibitor on human cervical carcinoma cells

Yuan ZHANG MD , Xiaoyan ZHANG MM , Yanhui LI MM , Xuan DU MM , Zehua WANG MD, PhD , Hongbo WANG MD ,

《医学前沿(英文)》 2009年 第3卷 第3期   页码 341-346 doi: 10.1007/s11684-009-0067-9

摘要: Phosphatidylinositol 3-kinase (PI3K) is a crucial cell survival pathway implicated in tumorigenesis because of its role in stimulating cell proliferation and suppressing apoptosis. This study was to investigate the regulation of proliferation and apoptosis by LY294002, an inhibitor of PI3K in cervical cancer cells and the expression of FLICE-like inhibitory protein (c-FLIP) . Human cervical cancer HeLa cells were used in this experiment and cultured. The cultured cells were treated with LY294002 at different concentrations (10, 25, 50 and 100µmol/L) for 6, 12, 24, and 48h before harvesting for evaluation. Cell viability was measured by 3-(4,5)-dimethylthiazol(-2-y1)-3,5-di-phenyltetrazoliumbromide (MTT) assay. Apoptosis was analyzed by flow cytometry. The expression of c-FLIP was detected by Western blot. Cell viability was inhibited by LY294002 significantly (<0.05). Flow cytometry analysis revealed that cell apoptosis was significantly increased in the presence of LY294002 as compared with the control group. Although the expression of c-FLIP was increased in a short time, the expression of c-FLIP was markedly suppressed after the treatment of LY294002 for 48h. These results suggested that the PI3K/Akt signal pathway might be involved in the regulation of cell apoptosis in cervical cancer cells. Moreover, the regulation of c-FLIP expression through PI3K/Akt signal pathway in cervical cancer cells was observed .

关键词: human cervical cancer cells     apoptosis     phosphatidylinositol 3-kinase (PI3K)/Akt     FLICE-like inhibitory protein    

ANTIVIRAL EFFECTS OF BACTERIOCIN AGAINST ANIMAL-TO-HUMAN TRANSMITTABLE MUTATED SARS-COV-2: A SYSTEMATIC

《农业科学与工程前沿(英文)》 2021年 第8卷 第4期   页码 603-622 doi: 10.15302/J-FASE -2021397

摘要:

The COVID-19 infections caused by SARS-CoV-2 have resulted in millions of people being infected and thousands of deaths globally since November 2019. To date, no unique therapeutic agent has been developed to slow the progression of this pandemic. Despite possessing antiviral traits the potential of bacteriocins to combat SARS-CoV-2 infection has not been fully investigated. This review summarizes the mechanisms by which bacteriocins can be manipulated and implemented as effective virus entry blockers with infection suppression potential properties to highly transmissible viruses through comprehensive immune modulations that are potentially effective against COVID-19. These antimicrobial peptides have been suggested as effective antiviral therapeutics and therapeutic supplements to prevent rapid virus transmission. This review also provides a new insight into the cellular and molecular alterations which have made SARS-CoV-2 self-modified with diversified infection patterns. In addition, the possible applications of antimicrobial peptides through both natural and induced mechanisms in infection prevention perspectives on changeable virulence cases are comprehensively analyzed. Specific attention is given to the antiviral mechanisms of the molecules along with their integrative use with synthetic biology and nanosensor technology for rapid detection. Novel bacteriocin based therapeutics with cutting-edge technologies might be potential substitutes for existing time-consuming and expensive approaches to fight this newly emerged global threat.

 

关键词: antimicrobial proteins / antiviral profiling of bacteriocins / antiviral therapeutics / immunomodulation / nanosensor technology / mutated SARS-CoV-2    

Influence of extracellular polymeric substances from activated sludge on the aggregation kinetics of

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1450-2

摘要:

• The NPs aggregation in the electrolyte solution is consistent with the DLVO theory.

关键词: Silver nanoparticles     Silver sulfide nanoparticles     Extracellular polymeric substances     Aggregation kinetics     Influence mechanisms    

Recovering humic substances from the dewatering effluent of thermally treated sludge and its performance

Yuning YANG,Huan LI

《环境科学与工程前沿(英文)》 2016年 第10卷 第3期   页码 578-584 doi: 10.1007/s11783-015-0827-5

摘要: The biologic treatment of the dewatering effluent from thermally treated sludge is difficult due to the high concentration of refractory humic substances. On the other hand, humic substances are an important source of organic fertilizer. In this study, a novel process using ferric coagulant was developed to recover humic substances from dewatering effluent for use as an organic fertilizer. When ferric coagulant was applied to raw dewatering effluent, up to 70% of humic substances were enmeshed by hydrolyzed ferric ions at an optimum pH of 4.5. The proper mass ratio of iron ions to humic substances was 0.6. In the recovered material, humic substances accounted for 24.2% of the total dry solids, and the amount of phosphorus (equivalent phosphorus pentoxide) was 6.2%. Heavy metals and other components all met the legal requirements for organic fertilizer. When the recovered material was applied to soybeans, the germination and growth of the seeds was significantly improved.

关键词: sewage sludge     humic substances     recovery     phosphorus     fertilizer    

Characterization of humic substances in bio-treated municipal solid waste landfill leachate

Guangxia QI, Dongbei YUE, Yongfeng NIE

《环境科学与工程前沿(英文)》 2012年 第6卷 第5期   页码 711-716 doi: 10.1007/s11783-012-0421-z

摘要: Considerable organic matter remains in municipal solid waste landfill leachate after biological treatments. Humic substances (HSs) dominate the organic matter in bio-treated landfill leachate. In this study, the HSs from landfill leachate treated by membrane bioreactor (MBR-HSs) were analyzed via elemental analysis, ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, and charge polarized magic-angle spinning- C-nuclear magnetic resonance. The characteristic absorption in the UV wavelength range indicated the presence of high C=C and C=O double bonds within the MBR-HSs. Compared with commercial HSs, MBR-HSs had lower carbon content [48.14% for fulvic acids (FA) and 49.52% for humic acids (HA)], higher nitrogen content (4.31% for FA and 6.16% for HA), lower aromatic structure content, and higher carbohydrate and carboxylic atoms of carbon content. FA predominantly had an aliphatic structure, and HA had less condensed or substituted aromatic ring structures than natural HA. The aromatic carbon content of MBR-HSs was lower than that of humus-derived HSs but higher than that of waste-derived HSs, indicating that MBR-HSs appeared to be more similar to humus-derived HSs than waste-derived HA.

关键词: bio-treated landfill leachate     humic substances     elemental analysis     spectroscopic characteristics    

Biosorption of Cu(II) to extracellular polymeric substances (EPS) from

Xiangliang PAN, Jing LIU, Wenjuan SONG, Daoyong ZHANG

《环境科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 493-497 doi: 10.1007/s11783-012-0416-9

摘要: Biosorption of extracellular polymeric substances (EPS) from sp. (cyanobacterium) with Cu(II) was investigated using fluorescence spectroscopy. Three fluorescence peaks were found in the excitation-emission matrix (EEM) fluorescence spectra of EPS. Fluorescence of peak A (Ex/Em= 275/452 nm) and peak C (Ex/Em= 350/452 nm) were originated from humic-like substances and fluorescence of peak B (Ex/Em= 275/338 nm) was attributed to protein-like substances. Fluorescence of peaks A, B, and C could be quenched by Cu(II). The effective quenching constants (lg K ) were 2.8–5.84 for peak A, 6.4–9.24 for peak B, and 3.48–6.68 for peak C, respectively. The values of lg K showed a decreasing trend with increasing temperature, indicating that the quenching processes were static in nature. The binding constants (lg K ) followed the order of peak A>peak B>peak C, implying that the humic-like substances in EPS have greater Cu(II) binding capacity than the protein-like substances. The binding site number, , in EPS-Cu(II) complexes for peaks A, B, and C was less than 1. This suggests the negative cooperativity between multiple binding sites and the presence of more than one Cu binding site.

关键词: biosorption     conditional binding constant     extracellular polymeric substances (EPS)     fluorescence quenching    

Rapid control of black and odorous substances from heavily-polluted sediment by oxidation: Efficiency

Kun Li, Min Yang, Jianfeng Peng, Ruiping Liu, Tista Prasai Joshi, Yaohui Bai, Huijuan Liu

《环境科学与工程前沿(英文)》 2019年 第13卷 第6期 doi: 10.1007/s11783-019-1171-y

摘要: Oxidants were proposed to rapidly control black and odorous substances in sediments. NaClO and KMnO4 had excellent efficiency to remove black and odorous substances. NaClO dramatically accelerated the release of organics, NH4+-N, P, and heavy-metals. Moderate oxidation had a limited effect on microbial communities. NaClO of 0.2 mmol/g was viewed to be the optimum option. The control of black and odorous substances in sediments is of crucial importance to improve the urban ecological landscape and to restore water environments accordingly. In this study, chemical oxidation by the oxidants NaClO, H2O2, and KMnO4 was proposed to achieve rapid control of black and odorous substances in heavily-polluted sediments. Results indicate that NaClO and KMnO4 are effective at removing Fe(II) and acid volatile sulfides. The removal efficiencies of Fe(II) and AVS were determined to be 45.2%, 94.1%, and 93.7%, 89.5% after 24-h exposure to NaClO and KMnO4 at 0.2 mmol/g, respectively. Additionally, rapid oxidation might accelerate the release of pollutants from sediment. The release of organic matters and phosphorus with the maximum ratios of 22.1% and 51.2% was observed upon NaClO oxidation at 0.4 mmol/g. Moreover, the introduction of oxidants contributed to changes in the microbial community composition in sediment. After oxidation by NaClO and KMnO4 at 0.4 mmol/g, the Shannon index decreased from 6.72 to 5.19 and 4.95, whereas the OTU numbers decreased from 2904 to 1677 and 1553, respectively. Comparatively, H2O2 showed a lower effect on the removal of black and odorous substances, pollutant release, and changes in sediment microorganisms. This study illustrates the effects of oxidant addition on the characteristics of heavily polluted sediments and shows that chemical oxidants may be an option to achieve rapid control of black and odorous substances prior to remediation of water environments.

关键词: Oxidants     Heavily polluted sediment     Black and odorous substances     Release behaviors     Microorganism    

Effect of natural aquatic humic substances on the photodegradation of bisphenol A

ZHAN Manjun, YANG Xi, KONG Lingren, YANG Hongshen

《环境科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 311-315 doi: 10.1007/s11783-007-0052-y

摘要: The photochemical degradation of bisphenol A (BPA) was studied in the presence of natural humic sub stances from different origins under simulated solar irradiation. BPA underwent insignificant direct photolysis in neutral water, but rapid photosensitized degradation in four humic substances solutions via pseudo-first-order reaction occurred. The photodegradation rate of BPA was insensitive to the different initial BPA concentrations and was inhibited in aerated solution compared with the deoxygenated medium. The reactive oxygen species (ROS) such as ?·OH and O produced from excitation of humic substances under irradiation was determined from the quenching kinetic experiment using molecular probe. The five main intermediate photoproducts of BPA in Nordic lake fulvic acid (NOFA) were tentatively identified using gas chromatography/mass spectrometer (GC/MS). Based on the identification of ROS and the analysis of photoproduct formation, the possible phototransformation pathways of BPA were proposed, involving the direct photolysis due to the energy transfer from the triplet state humic substance (HS) to BPA molecules and hydroxyl radical addition and oxidation as well.

关键词: irradiation     photoproduct     deoxygenated     possible phototransformation     bisphenol    

Impact and inhibitory mechanism of phenolic compounds on the formation of toxic Maillard reaction products

Jing TENG, Xiaoqian HU, Ningping TAO, Mingfu WANG

《农业科学与工程前沿(英文)》 2018年 第5卷 第3期   页码 321-329 doi: 10.15302/J-FASE-2017182

摘要:

As one of the dominant reactions occurring during thermal treatment of food, the Maillard reaction not only leads to the formation of aroma, browning color and taste compounds, but also contributes to the formation of some unpleasant toxic substances including acrylamide, heterocyclic amines and advanced glycation end products. Polyphenols, one of the most abundant antioxidants in the human diet, are contained in different kinds of foods. In this review, some recent studies on the impact of dietary polyphenols on the formation of acrylamide, heterocyclic amines and advanced glycation end products formed during the Maillard reaction are summarized, including the research work conducted with both chemical model systems and real food model systems; the possible inhibitory mechanisms of different polyphenols are also summarized and discussed in this review. Basically we found that some dietary polyphenols not only scavenge free radicals, but also react with reactive carbonyl species, thus lowering the formation of toxic Maillard reaction products. This review provides a useful theoretical foundation for the application of polyphenols in food safety, and suggests some directions for further study of natural products as inhibitors against the formation of toxic substances in thermally processed food.

关键词: advanced glycation end products     acrylamide     food safety     heterocyclic amine     Maillard reaction     polyphenols    

Design of a cyclic inhibitory CPG controller for the locomotion of a snakelike robot

LU Zhen-li, MA Shu-gen, LI Bin, WANG Yue-chao

《机械工程前沿(英文)》 2006年 第1卷 第4期   页码 396-402 doi: 10.1007/s11465-006-0046-7

摘要: The rhythmic locomotion of a creature is a self-excitation behavior of the CPG (central pattern generator), which makes it supremely adapted for environment. Based on this fact, firstly, a snake-ike robot controller with cyclic inhibitory CPG model was designed, and then the stability of a single neuron, CPG model and the NON ( neuron oscillator network) was analyzed. By implementing this control architecture to a simulator based on the mechanical dynamics of a real snake-like robot named Perambulator-I, we presented preliminary rules for parameter setting of the CPG controller to modulate the number of S shapes, the curve of the body shape, locomotion velocity, and the curve of the locomotion trajectory for serpentine locomotion. Moreover, we demonstrated that Perambulator-I can successfully exhibit serpentine locomotion by using the output of the proposed CPG controller. The results of this paper provide a realistic approach for designing an artificial CPG controller.

The early signal substances induced by heat stress in brains of mice

WANG Chunxu, WANG Hanxing

《医学前沿(英文)》 2008年 第2卷 第4期   页码 391-395 doi: 10.1007/s11684-008-0075-1

摘要: To study the effects of early signal substances induced by heat stress in brains of Kunming mice, six-month-old mice ( = 72) were pretreated with heat stress and subsequent ischemia/reperfusion by clipping of their bilateral cervical common arteries for 7 min. According to different treatments, animals were randomly divided into four groups: (1) normal control group; (2) heat stress pretreatment followed by ischemia and reperfusion group (HS/IR); (3) ischemia and reperfusion group (IR); (4) heat stress group (HS). Animals in the later three groups were subdivided into 3 subgroups (1 day, 4 days, 14 days), respectively. The changes in the expression of cAMP response element binding protein (CREB) and calcitonin gene-related peptide (CGRP) were detected by immunohistochemistry and computer image analysis methods. The results showed that compared with the normal group, the expressions of CREB in the hippocampal CA1 region increased significantly in the HS, HS/IR and IR groups ( < 0.05). Compared to the normal group, heat stress could result in CGRP excretion and redistribution in the cerebrum, with the highest level in the 4 d HS/IR group. Following heat stress, CGRP immunoreactivity was observed in varicose fibers and neuronal perikarya within the CA1 region. The results indicate that heat stress can induce CREB expression, which in turn stimulates CGRP secretion.

关键词: calcitonin gene-related     subsequent ischemia/reperfusion     computer     cerebrum     CGRP excretion    

Design, synthesis and HIV-RT inhibitory activity of novel thiazolidin-4-one derivatives

Hua CHEN, Zaihong GUO, Qingmei YIN, Xiaoxu DUAN, Yunjing GU, Xiaoliu LI

《化学科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 231-237 doi: 10.1007/s11705-010-1022-7

摘要: A series of 2-aryl-3-(4,5,6-trimethylpyrimidin-2-yl) thiazolidin-4-ones ( – ) and their derivatives bearing a lipophilic substituent, like acetoxy group ( – ), propionyloxy group ( – ), methyl ( and ) at C-5 on thiazolidin-4-one ring were designed, synthesized and evaluated for their HIV-RT inhibitory activity. Using self-catalyzed Pummerer reaction, compounds – and – were obtained in good yield (63.1% 75.2%). Preliminary anti-HIV-RT test of these derivatives indicated that compounds – , (propionyloxy group at C-5) showed moderate HIV-RT inhibitory activity and compounds and with methyl at C-5 showed a weak HIV-RT inhibitory activity. Structure activity relationship analysis suggested that the substituted groups on C-5 would be unfavorable to anti-HIV-RT activity and that the steric effect might play a critical role in the anti-HIV RT activity.

关键词: 5-subsituted thiazolidin-4-ones     Pummerer reaction     anti-HIV-RT activity     SARs    

标题 作者 时间 类型 操作

Screening of potential aquatic probiotics from the major microflora of guppies (

Aparna BALAKRISHNA, T. R. KEERTHI

期刊论文

Effects of oxidizing environment on digestate humification and identification of substances governing

期刊论文

Interaction and combined toxicity of microplastics and per- and polyfluoroalkyl substances in aquatic

期刊论文

Effects of phosphatidylinositol 3-kinase inhibitor on human cervical carcinoma cells

Yuan ZHANG MD , Xiaoyan ZHANG MM , Yanhui LI MM , Xuan DU MM , Zehua WANG MD, PhD , Hongbo WANG MD ,

期刊论文

ANTIVIRAL EFFECTS OF BACTERIOCIN AGAINST ANIMAL-TO-HUMAN TRANSMITTABLE MUTATED SARS-COV-2: A SYSTEMATIC

期刊论文

Influence of extracellular polymeric substances from activated sludge on the aggregation kinetics of

期刊论文

Recovering humic substances from the dewatering effluent of thermally treated sludge and its performance

Yuning YANG,Huan LI

期刊论文

Characterization of humic substances in bio-treated municipal solid waste landfill leachate

Guangxia QI, Dongbei YUE, Yongfeng NIE

期刊论文

Biosorption of Cu(II) to extracellular polymeric substances (EPS) from

Xiangliang PAN, Jing LIU, Wenjuan SONG, Daoyong ZHANG

期刊论文

Rapid control of black and odorous substances from heavily-polluted sediment by oxidation: Efficiency

Kun Li, Min Yang, Jianfeng Peng, Ruiping Liu, Tista Prasai Joshi, Yaohui Bai, Huijuan Liu

期刊论文

Effect of natural aquatic humic substances on the photodegradation of bisphenol A

ZHAN Manjun, YANG Xi, KONG Lingren, YANG Hongshen

期刊论文

Impact and inhibitory mechanism of phenolic compounds on the formation of toxic Maillard reaction products

Jing TENG, Xiaoqian HU, Ningping TAO, Mingfu WANG

期刊论文

Design of a cyclic inhibitory CPG controller for the locomotion of a snakelike robot

LU Zhen-li, MA Shu-gen, LI Bin, WANG Yue-chao

期刊论文

The early signal substances induced by heat stress in brains of mice

WANG Chunxu, WANG Hanxing

期刊论文

Design, synthesis and HIV-RT inhibitory activity of novel thiazolidin-4-one derivatives

Hua CHEN, Zaihong GUO, Qingmei YIN, Xiaoxu DUAN, Yunjing GU, Xiaoliu LI

期刊论文