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  • Author or Editor: L. Wei x
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Common wheat is a widely planted cereal in China, and vernalization is a crucial phase in wheat development. Although three major genes (VRN1, VRN2 and VRN3) are associated with the vernalization response, little is known about their expression profiles during wheat growth. In this study, we observed the spike differentiation process in spring wheat variety XC2 and winter wheat variety J841 and used qRT-PCR to analyze the expression patterns of three VRN genes in the leaves of these wheat varieties during development under vernalization versus non-vernalization treatment under long-day conditions. We also analyzed the expression patterns of VRN1 and VRN3 in the apical meristem. In both spring and winter wheat, the spikes remained at the single ridge state and did not differentiate under vernalization treatment. Spike differentiation completed one week earlier in XC2 spring wheat after vernalization treatment compared with non-vernalization conditions. Vernalization treatment significantly upregulated VRN1 and VRN3 expression in leaves under long-day conditions, whereas VRN2 expression was sharply reduced. The expression of VRN3 was low in shoot apical meristems, while VRN1 was highly expressed in shoot apical meristems when floral primordia began to differentiate and develop, suggesting that VRN1 functions independently in leaves and shoot apical meristems.

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Sequestration of radioactive nickel (63Ni2+) in fly ash coming from hospital wastes incineration plant by incorporating nano-goethite as a function of pH, particle size and the ratio of solid and liquid was investigated under the batch leaching experiments. The synthetic nanogoethite was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and specific surface area (SSA). The admired needle nanogoethite was obtained in terms of XRD, TEM and SSA analysis. Approximate 5% of 63Ni2+ was desorbed from the nanogoethite/fly ash composite under the circum natural pH conditions. The ratio of solid to liquid has little effect on desorption of 63Ni2+ from nanogoethite/fly ash composite. These results indicate that the radioactive nickel in fly ash can be sequestrated by incorporating nanogoethite. The results may play significantly a role in immobilization in situ of trace radionuclides in the natural environment.

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The inhibitory effects of three berberine alkaloids (BAs) from Coptis chinensis Franch on Bifidobacterium adolescentis growth were investigated by microcalorimetry. The growth rate constant (k) and maximum heat-output power (Pmax) decreased and peak time of maximum heat-output power (tp) prolonged with the increase of BAs concentration. Half inhibitory ratios (IC50) BAs were respectively 790.3 (berberine), 339.6 (coptisine) and 229.8 μL−1 (palmatine), which indicated the sequence of their antimicrobial activity: berberine<coptisine<palmatine. Combined with previous findings, the sequence which could show the bioactivity of Bacillus shigae and Escherichia coli was: berberine>coptisine>palmatine. The structure-function relationship of BAs indicated that the functional group methylenedioxy or methoxyl at C2 and C3 might be the major group inducing the activities of BAs on E. coli and B. adolescentis. Meanwhile, the substituent groups at C2, C3, C9 and C10 almost had equal effect on B. shigae.

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To control the quality of Euonymus fortunei (Turcz.) Hand.-Mazz., a simple and reliable method of high-performance liquid chromatography (HPLC) coupled with photodiode array detector (PAD) was developed for both fingerprint analysis and quantitative determination. Four representative flavonoids, namely, kaempferol-3-O-β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl-7-O-β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranoside (I), kaempferol-3,7-O-α-dirhamnopyranoside (II), apigenin-7-O-β-D-glucopyranoside (III), and kaempferol-3-(4″-O-acetyl)-O-α-L-rhamnopyranoside-7-O-α-L-r hamnopyranoside (IV) isolated from E. fortunei, were used as reference compounds and simultaneously determined by the validated HPLC method. The unique properties of the chromatographic fingerprint were validated by analyzing 11 batches of E. fortunei, E. japonicus, E. laxiflorus, E. myrianthus, and E. hamiltonianus samples. Our results revealed that the chromatographic fingerprint combined with similarity measurement could efficiently identify and distinguish E. fortunei from the other investigated Euonymus species.

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Electronic stopping power of 19F in Ni, Pd and Gd was measured and compared to Mstar and SRIM calculation as well as experimental results published in literature. It turns out that the present electronic stopping power agrees reasonably well with them.

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Patrinia scabra Bunge has long been used in clinic as a traditional Chinese medicine for treating leukemia and cancer and regulating host immune response. Despite their wide use in China, no report on system analysis on their chemical constituents is available so far. The current study was designed to profile the fingerprint of ethyl acetate extract of it, and in addition, to characterize the major fingerprint peaks and determine their quantity. Therefore, a detailed gradient high-performance liquid chromatography was described to separate more than 30 compounds with satisfactory resolution in P. scabra Bunge. Based on the chromatograms of 10 batches samples, a typical high-performance liquid chromatographic (HPLC) fingerprint was established with 23 chromatographic peaks being assigned as common fingerprint peaks. Furthermore, a quadrupole time of flight mass spectrometry (Q-TOF/MS) was coupled for the characterization of major compound. As (+)-nortrachelogenin was the most predominant compound in P. scabra Bunge, the quantification on it was also carried out with the method being validated. As a result, (+)-nortrachelogenin was found to be from 1.33 to 2.21 mg g−1 in this plant material. This rapid and effective analytical method could be employed for quality assessment of P. scabra Bunge, as well as pharmaceutical products containing this herbal material.

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This paper develops an instrumental analytical approach for detection of fourteen polycyclic aromatic hydrocarbons (PAHs) in edible oil samples using gel permeation chromatography (GPC) and ultra-high performance liquid chromatography (UHPLC) coupled with diode array detector (DAD), and fluorescence detector (FLD). The GPC was used to remove triglycerides from edible oil samples. The extracted samples were then detected using UHPLC—DAD—FLD. In order to obtain good separation and high reproducibility, the UHPLC—DAD—FLD experimental condition was optimized. The PAHs including three groups of isomeric PAHs can be separated completely in 12 min using BEH Shield RP 18 column with a suitable gradient elution program. The mean recoveries were in the range of 73–110% with an acceptable reproducibility (RSD < 10%, n = 3). During real sample analysis, the method can decrease the chance of false positives with both DAD and FLD being used simultaneously. The results indicate that the approach is simple, easy, and acceptably reproducible, thereby showing great potential as a method for detection of fourteen PAHs contained in edible oil samples.

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Abstract  

Antifreeze protein (AFP) can lower the freezing point by inhibiting the growth of ice crystals. In this article, the thermal hysteresis activity (THA) of a plant AFP was measured with differential scanning calorimetry (DSC). As is shown, when the amount of ice in the sample was less than 5% THA of this AFP reached as high as 0.35°C. The secondary structure of this AFP was studied with circular dichroism (CD). The CD spectrum from 195to 240 nm indicated a well-defined secondary structure consisting 11% α-helix, 34%antiparallel β-sheet and 55% random coil.

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We studied the removal process of excessive free carbon in the nano-SiC powder by TG-DTA-MS, XRD and TEM three methods. The studies showed that the temperature of removing excessive free carbon in the nano-SiC powder should be about 750°C in air.

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