Publications by authors named "Lumei Pu"

In this work, different injection modes (single injection, overlapping injection, and continuous injection) of countercurrent chromatography were used and compared for the isolation and purification of glabridin from the crude extract of Glycyrrhiza glabra. The two-phase solvent system consisting of n-hexane/ethyl acetate/methanol/water (5:4:5:4, v/v) was employed as stationary and mobile phases. Compared with single injection mode, both overlapping injection and continuous injection modes exhibited higher separation efficiency at the same sample loading capacity.

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A bis(salamo)-like chemical sensor HL ((1E,3E)-2-hydroxy-5-methylisophthalaldehyde O,O -di(3-((((E)-(2-hydroxynaphthalen-1-yl)methylene)amino)oxy)propyl) dioxime) was constructed. HL is capable of recognizing BO in HO/DMF (1:9, v/v) solution by both fluorescent and colorimetric channels, bright green fluorescence was turned on when BO was added to HL and changed from colorless to yellow in natural light. The detection limit was 3.

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In this work, a high-speed shear extraction off-line coupling high-speed countercurrent chromatography method was developed to separate maslinic acid and oleanolic acid from olive pomace. To improve extraction efficiency, the polar disparity between maslinic acid and oleanolic acid necessitated the concurrent utilization of both polar and non-polar solvents during high-speed shear extraction. Then, the high-speed shear extraction was directly feed to high-speed countercurrent chromatography for subsequently separation.

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Background: Combination therapy employing multiple drugs has been shown to enhance the efficacy of cancer treatment. Chlorambucil (Chl) and 6-mercaptopurine (6MP) are the first-line medicines for chronic lymphocytic leukemia and ovarian cancer. However, both were limited by their short half-life of disintegration, unsatisfactory water solubility, and adverse reactions.

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Lignin is a crucial component in the wound tissue of tubers. The biocontrol yeast Meyerozyma guilliermondii increased the activities of phenylalanine ammonia lyase, cinnamate-4-hydroxylase, 4-coenzyme coenzyme A ligase, and cinnamyl alcohol dehydrogenase, and elevated the levels of coniferyl, sinapyl, and p-coumaryl alcohol. The yeast also enhanced the activities of peroxidase and laccase, as well as the content of hydrogen peroxide.

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Herein, gadolinium tannate was simply and conveniently coated on the surface of palygorskite by reaction of a coordination polymer formed between tannic acid and Gd. The palygorskite-tannate gadolinium-polyvinyl alcohol integrated composite (PAL@Gd@PVA) is successfully prepared after the introduction of polyvinyl alcohol onto the palygorskite-tannate gadolinium. The structure is characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy analysis.

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Ochratoxin A (OTA) is a very important mycotoxin. However, there are few studies on the removal of OTA in wine because of the great influence on product quality and difficulty in practical application. A nano-MgO-modified diatomite ceramic membrane (MCM) with a high positive charge was prepared and applied to remove OTA in wine.

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is an important postharvest pathogen of pomaceous fruit and a causal agent of blue mold or soft rot. In this study, we investigated the effect of ambient pH on growth, ultrastructure alteration, and pathogenicity of , as well as accumulation of patulin and expression of genes involved in patulin biosynthesis. Under different pH, the fungus was routinely cultured and collected for growth, pathogenicity, patulin production, and gene expression studies using transmission electron microscopy, apple inoculation, HPLC, and RT-qPCR methods.

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A newly synthesized fluorescent chemosensor HL was explored for detecting BO, characterized by H NMR spectrum, mass spectrum and fluorescence spectra. During the detection process of BO, the fluorescence is significantly enhanced and naked eye recognition can be performed under 365 nm UV light without any interference by other typical anions. The limit of detection is as low as 6.

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Amino and thiolated aptamers are the main aptamers used to construct label-free electrochemical impedimetric aptasensors. In this study, the modification performance and electrochemical properties of amino aptamers and thiolated aptamers were studied in the construction of label-free impedimetric sensors. The results showed that the initial modification density of amino aptamers was higher than that of thiol aptamers.

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Four new hetero-pentanuclear 3d-4f complexes [Zn(L)La(NO)(OEt)(HO)] (1), [Zn(L)Ce(NO)(OMe)(MeOH)] (2), [Zn(L)Pr(NO)(OEt)(EtOH)] (3) and [Zn(L)Nd(NO)(OMe)(MeOH)] (4) were synthesized by the reactions of a newly synthesized octadentate bis(salamo)-based tetraoxime ligand (HL) with Zn(OAc)·2HO and Ln(NO)·6HO (Ln = La, Ce, Pr and Nd), respectively, and characterized elemental analyses, FT-IR, UV-Vis spectroscopy and single crystal X-ray crystallography. The X-ray crystallographic investigation revealed that all Zn ions were located in NO coordination spheres, and possessed a trigonal bipyramid coordination environment. The Ln ion lay in an O coordination sphere, and adopted a distorted square antiprismatic coordination environment.

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In this study, we report the preparation and characterization of the PVA-DTPA-Gd conjugate as a potential MRI contrast agent (CA). The value and the / ratio were about 5.6 mM s and 1.

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A simple and sensitive label-free impedimetric aptasensor for rapid determination of ochratoxin A (OTA) has been developed, which was based on the combination between thiolated aptamer and gold nanoparticles by layer-by-layer self-assembly. Because of the interaction between aptamer and OTA, the relative normalized electron-transfer resistance (ΔR) values obtained by electrochemical impedance spectroscopy (EIS) was proportional to the concentration of OTA and showed a good linear relationship from 0.1 to 10.

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A highly selective fluorescent sensor HL based on a bis(salamo)-type compound with two NO chelating moieties as ionophore was successfully developed. Sensor HL was found to have excellent selectivity for BO over many other anions (Br, CI, CN, CO, HCO, HPO, HSO, NO, OAc, SO, SCN, SO, Hcy (homocysteine) and HO), and it exhibited an approximately 150-fold enhancement of the fluorescence response to BO in Tris-HCl buffer (DMF/HO = 9:1, v/v, pH = 7) solutions. Significantly, its fluorescence intensity was enhanced in a linear fashion with increasing concentrations of BO.

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[Co₂(L)Ce(OAc)₃(CH₃CH₂OH)]·1.5CH₃OH∙0.5CH₂Cl₂, a heterotrinuclear Co(II)-Ce(III) bis(salamo)-type complex with a symmetric bi(salamo)-type ligand H₄L and an acyclic naphthalenediol moiety, was designed, synthesized and characterized by elemental analyses, FT-IR, UV-Vis and fluorescence spectroscopy and X-ray crystallography.

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Fusarium rot of muskmelon, caused by Fusarium spp., is one of the most important postharvest decays, that not only causes economic losses but leads to trichothecenes contamination. A rapid and sensitive method was developed for neosolaniol (NEO) analysis in muskmelon inoculated with F.

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Studies were conducted to determine the role of 3-methylthioproprionic acid (MTPA) in the pathogenicity of potato stem canker, Rhizoctonia solani, and the concentrations required to inhibit growth of R. solani under laboratory and plant house-based conditions. The experiments were laid out in a completely randomized design with five treatments and five replications.

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This paper described a plasma degradation of Brilliant Green (BG) by glow discharge electrolysis. Various influencing factors such as the voltage, the distance between cathode and anode were examined. Ultraviolet (UV) absorption spectra, gas chromatogram-mass spectrum (GC-MS), and chemical oxygen demand (COD) were used to monitor the degradation process and to identify the major oxidation intermediates.

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