MOLECULES
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2017
·Vol. 22
·期 9
·1494
·
IF 2.861
Yan Du,Zhibin Wang,Libo Wang,Mingjie Gao,Liqian Wang,Chunli Gan,Chunjuan Yang
A rapid and sensitive Ultra High Performance Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometry (UHPLC-ESI-MS/MS) method was developed and validated to simultaneously determine the concentration of seven phenolic acids (syringic acid, ferulic acid, caffeic acid, vanillic acid,p-coumaric acid, 3,4-dihydroxybenzoic acid and 4-hydroxybenzoic acid) in rat plasma after oral administration ofEchinacea purpureaextract. After mixing with the internal standard (IS), butylparaben, plasma samples were prepared by liquid–liquid extraction with ethyl acetate. The separation was performed using the Agilent Eclipse Plus C18column (1.8 μm, 2.1 mm × 50 mm) with a gradient system consisting of solution A (0.1% acetic acid in water) and solution B (methanol) at a flow rate of 0.3 mL/min. The detection was accomplished by a multiple reaction monitoring (MRM) mode with electrospray ionization (ESI). The method was validated in terms of linearity, precision, accuracy, extraction recovery, matrix effect and stability. This method was successfully applied to study the pharmacokinetic properties of the seven compounds after oral administration ofEchinacea purpureaextract in rats.Keywords:Echinacea purpurea;phenolic acids;UHPLC-ESI-MS/MS;pharmacokinetics
研究领域:
分析化学
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药理学
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植物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLUTION CHEMISTRY
·
2018
·Vol. 47
·期 4
·705-714
·
IF 1.401
Li Qiang,Liu Bijun,Mu Wanjun,Yu Qianhong,Tian Yin,Liu Guoping,Yang Yuchuan,Li Xingliang,Luo Shunzhong
Glufosinate, an analogue of glutamic acid (also known as phosphinothricin), is an important herbicide. The protonation constants of glufosinate were determined by means of potentiometric titrations at variable temperatures with ionic strength 0.5 mol·L −1 (NaCl solution). The heat effects of the protonation reactions of glufosinate were measured by direct calorimetry. NMR spectroscopies have demonstrated that the first protonation site occurs on the nitrogen atom in the amino group, followed by one of the oxygen atoms in the phosphono group, and finally the carboxyl oxygen atom. This trend is in good agreement with the enthalpy of protonation and crystal structure results. These data will help to predict the speciation of glufosinate in physiological systems.
研究领域:
植物学
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化学
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环境科学
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产品关联
DOI
高影响因子
HARMFUL ALGAE
·
2018
·
IF 4.138
Miaomiao Zhao,Xinyi Chen,Ning Ma,Qiuyue Zhang,Dong Qu,Ming Li
To form Microcystis blooms, Microcystis must be competitively dominant to other phytoplankton species to produce enough biomass. The aim of this study was to determine the competition mechanisms between Microcystis aeruginosa and Scenedesmus obliquus . M. aeruginosa and S. obliquus were separately cultured in the filtrate of mono and mixed cultures of M. aeruginosa and S. obliquus with varying treatments concerning N, P and iron availability. The inhibition rate for M. aeruginosa was 20–31% when cultured in mono and mixed culture filtrates enriched with N and P, but this rate was reduced to −15 to 19% when cultured in filtrates enriched with N, P and iron. The inhibition rate for M. aeruginosa decreased from 80 to 100% to 11–39% in dialytic filtrates. However, there were no differences in inhibition rate for S. obliquus, regardless of filtrate or dialytic filtrate treatments. The potential allelochemical, 2-butyl-octanol (0.144 mg L −1 ), was found to have little inhibitory effect to M. aeruginosa or S. obliquus . Thus, previously reported allelopathy to Microcystis would be overestimated. We also report a new mechanism in phytoplankton competition in this study. The phytoplankton secreted humic acid-like substances that can reduce the bioavailability of iron, resulting in the inhibition of other phytoplankton.
研究领域:
生态学
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环境科学
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DOI
PubMed
高影响因子
Toxins
·
2021
·Vol. 13
·期 5
·343
·
IF 4.546
Xudong Luo,Li Ding,Xiangdong Ye,Wen Zhu,Kaiyue Zhang,Fangyan Li,Huiwen Jiang,Zhiwen Zhao,Zongyun Chen
Scorpion venoms are rich resources of antimicrobial peptides (AMPs). While the short-chain noncysteine-containing AMPs have attracted much attention as templates for drug development, the antimicrobial potential of long-chain noncysteine-containing AMPs has been largely overlooked. Here, by using the online HeliQuest server, we designed and analyzed a series of 14-residue fragments of Smp43, a 43-residue long-chain noncysteine-containing AMP identified from the venom ofScorpio maurus palmatus. We found that Smp43(1-14) shows high antimicrobial activity against both Gram-positive and Gram-negative bacteria and is nontoxic to mammalian cells at the antimicrobial dosage. Sequence alignments showed that the designed Smp43(1-14) displays a unique primary structure that is different from other natural short-chain noncysteine-containing AMPs from scorpions, such as Uy17, Uy192 and IsCT. Moreover, the peptide Smp43(1-14) caused concentration-dependent fluorescence increases in the bacteria for all of the tested dyes, propidium iodide, SYTOXTMGreen and DiSC3-5, suggesting that the peptide may kill the bacteria through the formation of pore structures in the plasma membrane. Taken together, our work sheds light on a new avenue for the design of novel short-chain noncysteine-containing AMPs and provides a good peptide template with a unique sequence for the development of novel drugs for use against bacterial infectious diseases.Keywords:scorpion venom;noncysteine-containing AMPs;Smp43;Smp43(1-14);antimicrobial resistance;HeliQuestKey Contribution:Smp43(1-14), a short fragmented peptide of Smp43, was designed as a novel antimicrobial peptide with a unique sequence and potent antimicrobial activity.
研究领域:
生物化学
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药理学
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微生物学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2022
·
IF 4.889
Danyang Cao,Jie Zhang,Yuxiang Nie,Shanshan Wang,Xin Feng,Jiahua Zhu,Xiaohua Lu,Liwen Mu
In this work, the natural lubricating components from Cork bark (CB) and Populus bark (PB) were obtained by catalytic reduction fractionation and liquid–liquid extraction. GC–MS, 2D-NMR, and GPC some techniques were used to characterize the chemical composition of the CB and PB extract. The main components of CB and PB are suberin-derived aliphatic and alkaloid, respectively. CB and PB extract have been demonstrated as efficient organic lubricating additives to reduce wear rate and stabilize friction coefficient of paraffin lubricant. Interestingly, the addition of CB or PB extract in paraffin shows better lubrication performance as compared with commercial lubricants. In addition, XPS results show that some compounds such as suberin-derived aliphatic and alkaloid from bark could enhance lubricating oil film to reduce friction and wear. Overall, this work will replace the conventional petroleum based lubricating additives and open a new application venue for bark to improve product value.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Guangyuan Hu,Zhiwei Wang,Changqing Xia,Xinliang Wang,Hongxing He,Zhifeng Nie,Shixing Wang,Weili Li
The recovery of gold from industrial effluents is crucial for environmental conservation, sustainable resource management, and promoting the green development of gold resources. We designed a Zr-based MOF (UKM-78) by incorporating functional organic ligands that resemble amino groups, using MOFs’ inherent sieving effect for ion separation. This novel material exhibited enhanced gold recovery under acidic conditions, with an adsorption capacity three times and an adsorption rate four times higher than those of nonfunctionalized UKM-77. Notably, UKM-78 efficiently captured gold solutions at concentrations as low as 1 ppm and achieved an adsorption rate exceeding 90%, owing to the electrostatic interactions and coordination between its functionalized groups and the synergistic effect of its porous structure. Despite multiple regeneration cycles, UKM-78 retains 99.4% of its adsorption capacity. X-ray photoelectron spectroscopy (XPS), kinetic studies, and thermodynamics collectively demonstrated that Au(III) binding on UKM-78 involved cooperative electrostatic interactions and chemical adsorption through coordination. This study highlights the potential of MOFs for efficient and sustainable recovery of gold from complex waste streams.
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2025
·
IF 2.8
Hongdan Ao,Ling Lin,Di Pu,Xinmin Zhang,Yuanhao Luo,Meirong Wang,Zheng Li,Ren Ren
Oil-based drilling fluid is widely used in deep and ultra-deep well drilling, but long-term use will lead to cutting accumulation and performance degradation and cannot be recycled. In this study, octadecyl acrylate (SA), divinylbenzene (DVB), and cetyl dimethylallyl ammonium chloride (C16-DMAAC) were used as raw materials to synthesize a polymer particle SDCD that can be stably dispersed in the oil–water two-phase in ethanol solution as a waste oil-based drilling fluid flocculant. The structure of SDCD was characterized by FT-IR, 1 HNMR, SEM, XPS, Zeta potential, and particle size distribution, and its flocculation mechanism in waste oil-based drilling fluid was analyzed. The results show that the fine particle size of SDCD makes it easy to disperse in the mud, and the positive potential characteristics make it capable of electrostatic adsorption with kaolin. At the same time, the pore structure can provide a specific surface area to enhance the adsorption. When the dosage of SDCD was 2.5 wt%, the flocculation rate reached 87.66%, the slurry showed good rheology and emulsion stability, and it still met the performance standard after 150°C hot rolling again. In addition, SDCD was successfully applied to waste mud treatment on site, which significantly reduced the solid content and improved the mud performance. This study provides an effective method for the recycling of waste oil-based drilling fluid and helps to reduce drilling costs.
研究领域:
石油工程
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材料科学
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环境工程
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产品关联
DOI
高影响因子
Separations
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2025
·Vol. 12
·期 12
·
IF 2.7
Rong Zha,Ying Huang,Ling Zhu,Jiali Tan,Zhenfeng Xiong,Baoyan Chi
Hydroxamic acid extractants, such as LIX984, demonstrate high efficiency in extracting nickel from electron-free nickel waste solutions; however, they suffer from a slow extraction rate. This study investigated the effect of adding 2–5 vol.% of three organophosphate extractants (P507, P204, and Cyanex272) to LIX984. The results show that incorporating 2–5 vol.% of P507 or Cyanex272 significantly improves both extraction efficiency and kinetics. The addition of organophosphate extractants increased the extraction rate by 1.5–10 times, indicating a direct correlation between the extractant content and the acceleration of the extraction process, with higher concentrations yielding faster extraction. Compared to the use of LIX984 alone, where nickel extraction efficiency was only 46%, the addition of 5 vol.% P507 increased efficiency to over 99%, with a substantial improvement in extraction rate. Similarly, 2 vol.% P204 achieved a nickel removal efficiency of 99.8%. In non-electroplating waste solutions (pH 4–6), selective removal of iron and zinc impurities was achieved by first adding 2–5 vol.% P204 or P507, followed by adjusting the pH to 6–7 and using a mixture of organophosphate extractants. The spent electroless nickel plating baths were then treated with LIX984 combined with organophosphoric acid extractants, yielding nickel salt solutions of higher purity. Thus, P507, P204, and Cyanex272 serve as effective promoters for the hydroxamic acid extractant LIX984, resulting in both enhanced nickel extraction efficiency and faster extraction kinetics.
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Bangyuan Song,Yifan Li,Fei Han,Yandong Lu
Membrane distillation (MD) shows great potential in hypersaline water treatment, but it is invariably constrained by temperature polarization. Conductive heating vacuum membrane distillation (CHVMD), a single-pass system without recirculating feed, effectively alleviates temperature polarization by introducing a thermal conducting layer that enhances the transfer of external heat to the membrane-water interface. However, this process exacerbates concentration polarization, raising the scaling potential. Gypsum scaling, a common issue in MD, has been effectively alleviated by using carboxyl antiscalants. However, the mechanisms by which different carboxyl antiscalants influence gypsum scaling in MD remain poorly understood. In this study, the performance and mechanism of three carboxyl antiscalants—polyacrylic acid (PAA), polymethacrylic acid (PMAA) and hydrolyzed polymaleic anhydride (HPMA)—in CHVMD using gypsum solution as the feed were investigated. The results show that these carboxyl antiscalants enhance the membrane durability in the single-pass CHVMD system, while improving both initial and stabilized flux in the order: PAA > HPMA > PMAA. PAA exhibits a more pronounced effect on reducing the evaporation enthalpy of water through the formation of intermediate water, and lowering the resistance to heat and mass transfer with the formation of vertical, large lamellar gypsum crystals, achieving an initial flux of 12.79 kg/m 2 h and a stabilized flux of 10.20 kg/m 2 h. For PMAA, increasing feed salinity significantly reduces the evaporation enthalpy, and lowers the transfer resistance by the formation of larger needle-like gypsum crystals, thereby obtaining the highest initial flux of 15.45 kg/m 2 h and stabilized flux of 11.35 kg/m 2 h.
研究领域:
环境工程
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水处理技术
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Microbiology
·
2023
·
IF 5.2
Shikai Zhang,Qing Xu,Changbo Ji,Xiaoyu Han,Yang Zhou,Chao Liang,Linran Ma,Weijian Sun,Yanling Li,Zhengyou Yang,Fengchun Zhao,Yuan Tian
Small molecule-induced fermentation of the endophytic fungus Diaporthe sp. AC1 originated from Artemisia argyi was executed to investigate its secondary metabolites. It was fermented in a culture medium containing 5-hydroxytryptophan (5-HTP), 1-methyl-L-tryptophan (1-MT), and tryptamine (TA), respectively. The antibacterial activities of crude extracts against pathogenic bacteria and pathogenic fungi were determined by using the Oxford cup method, while the cytotoxicity of crude extracts against cancer cells was determined by using the MTT method. The results showed that the secondary metabolites of Diaporthe sp. AC1 induced by 1-MT exhibited optimal antibacterial activity and tumor cytotoxicity. The induction conditions of 1-MT were optimized, and the antibacterial activities and tumor cytotoxicity of crude extracts under different induction conditions were investigated. As indicated, the optimal moment for 1-MT addition was before inoculation and its optimal concentration was 0.25 mM. Under these conditions, Diaporthe sp. AC1 was fermented and approximately 12 g of crude extracts was obtained. The crude extracts were then separated and purified to acquire nine monomer compounds, including three new compounds ( 1 – 3 ) and six known compounds ( 4 – 9 ). The antibacterial activities of the compounds against pathogenic bacteria and pathogenic fungi were investigated by using the microdilution method, while their cytotoxicity against cancer cells was analyzed by using the MTT method. The results demonstrated that Compound 1 exhibited moderate antibacterial activities against Verticillium dahlia , Fusarium graminearum, and Botrytis cinerea , as well as a low inhibitory activity against Listeria monocytogenes . Nevertheless, Compound 1 showed significant cytotoxicity against five cancer cells, with IC 50 ranging from 12.26 to 52.52 μM. Compounds 2 and 3 exhibited negligible biological activity, while other compounds showed detectable inhibitory activities against pathogenic bacteria and cancer cells.
研究领域:
微生物学
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药理学
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植物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2011
·
IF 4.194
Jun Cao,Ping Li,Ling Yi
A new CE system using ionic liquids coated multi-walled carbon nanotubes (ILs-MWNTs) as pseudostationary phase was developed for the simultaneous determination of four flavonoids, four phenolic acids and two saponins. Several parameters affecting the separation were studied, including the choice of ILs, ILs-MWNTs concentration, the respective use of ILs and MWNTs, buffer pH, SDS concentration and borate content. Results revealed that the addition of ILs-MWNTs in running electrolytes enhanced the separation of target compounds compared to conventional micelle because the surface of carbon nanotubes interacted favorably with the analytes. Under the optimum conditions, a baseline separation was achieved for these analytes within 11 min in a 41.5 cm of effective length fused-silica capillary. At a voltage of 28.0 kV, the separation was carried out in a 10 mM borate buffer (pH 9.0) containing 100 mM SDS, 6% propanol and 4 μg mL −1 ILs-MWNTs. All calibration curves showed good linearity ( r 2 > 0.9990) within the test ranges. The intra- and inter-day precisions as determined from standard solutions were below 3.30% and 6.23%, respectively. The recoveries for ten compounds were found to range from 85.5 to 101.8%. The method was successfully applied for the determination of three types of compounds in Qishenyiqi dropping pills. Our experimental results indicated that the proposed method offered new opportunities for the analysis of complex samples.
研究领域:
分析化学
·
药物分析
✓ 已验证
DOI
高影响因子
Chinese Journal of Natural Medicines
·
2012
·
IF 0
Yi LI,Ming RUAN,Jian-Guang LUO,Ling-Yi KONG
A novel on-line method using high performance liquid chromatography (HPLC) with a diode array detector (DAD) and a chemiluminescence (CL) detector was successfully developed for simultaneously analyzing the antioxidant efficacies of 15 components in Guan-Xin-Ning (GXN) injection, a traditional Chinese medicinal preparation consisting of Radix Salvia miltiorrhiza and Rhizoma Ligusticum chuanxiong for the treatment of coronary heart disease and angina pectoris. The analytical conditions were optimized, validated and applied to determine H 2 O 2 inhibition rates of the 15 phenolic acids in GXN injections from 14 different production batches. The results showed that antioxidant diversities were found in the 15 compounds and that danshensu, protocatechuic aldehyde and rosmarinic acid were largely responsible for the antioxidant activity of GXN injection (25.82%-51.19%). In addition, 14 batches of GXN injections were divided into five groups corresponding with five different factories by principal component analysis (PCA) assay. Therefore, the proposed HPLC-DAD-CL method was simple, rapid and low-cost for screening antioxidant constituents in a complex system, which can be used to reveal the antioxidant mechanism of GXN injection and is applicable for its quality control in terms of activity, which was different from the routine chemical assessment.
研究领域:
中药学
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分析化学
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）