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  • Author or Editor: Tao Zheng x
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A simple and accurate high-performance thin-layer chromatography (HPTLC)-bioautographic method was developed for the quantitative analysis of magnolol and honokiol in the herbal medicine Magnoliae officinalis Cortex. The samples were separated on a silica gel HPTLC plate with a mixture solution of toluene-methanol (10:1, v/v) as the mobile phase. Spots were visualized by dipping in 2,2-diphenyl-1-picrylhydrazyl radical (DPPH*) reagent and measured at a wavelength of 550 nm in a reflection mode, scanning after derivatization for 40 min. The method had excellent linearity (r 2 = 0.9939 for magnolol and r 2 = 0.9989 for honokiol, respectively) in the concentration range of 0.16–0.97 mg spot−1 for both analytes. The recoveries were 94.5–105.9% for magnolol and 86.6–103.4% for honokiol, respectively. The established HPTLC-bioautographic method was evaluated comprehensively in quantitative and antioxidant activity analysis of magnolol and honokiol in Magnoliae officinalis Cortex and various plants.

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Abstract  

The effect of different solid soil components of calcareous soils on the retention of SeO3 has been investigated by a batch technique and selective extraction method. The sorption and desorption isotherms of SeO3 on the untreated calcareous soil and the three treated soils were determined at 20°C, pH 7.8±0.2 and in the presence of 0.001M CaCl2. It was found that all isotherms are linear, the sorption-desorption hysteresis for untreated soil and treated soils is obvious and the retention of SeO3 in calcareous soil is mainly attributed to the oxides.

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Abstract  

The kinetics of particle-diffusion controlled ion exchange in the ternary system of cations UO 2 2+ –Na+–H+–001×7 strong acidic resin has been studied. In the [R–H+]/(Na++UO 2 2+ ) system, the change of the amount of Na+ in the resin phase with time showed a high peak. In the [R–Na+]/(H++UO 2 2+ ) system, the change of the amount of H+ in the resin phase with time also showed a high peak. In the [R2–UO 2 2+ ]/(H++Na+) system, the change of amount of H+ in the resin phase with time showed merely a small peak. This kinetic character of the ternary ion exchange system in the finite solution volume has been analyzed according to the Nerst-Planck equation, and on the whole, the trend of the experimental results is consistent with the resulting numerical solution of the set of Nerst-Planck equations.

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The proportion of pathogenic microorganisms in the microbial world is relatively small, while their threat to human health, economic development and social stability is severe. The quantity and variation of Science Citation Index (SCI) literature related to pathogenic microorganisms may reflect the level of relevant research and the degree of attention. Here we compared trends in the quantity and variety of SCI literature relating to certain important pathogenic microorganisms published by scientists from United States and China from 1996 to 2010 by searching the Science Citation Index database. The pathogenic microorganisms in this study comprise two categories of pathogens: Bacillus anthracis, Yersinia pestis, Francisella tularensis, Ebola virus, Burkholderia pseudomallei, which belong to biodefense-associated pathogens (BDAPs) and the human immunodeficiency virus (HIV), SARS coronavirus, hepatitis B virus (HBV), Mycobacterium tuberculosis, influenza virus, which belong to the commonly encountered health-threatening pathogens. Our results showed that the United States (US) published much more SCI literature on these pathogens than China. Furthermore, literature on BDAPs published by scientists from the US has increased sharply since 2002. However, the numbers of literature relating to CEHTPs from China has demonstrated a gradual increase from 1996 to 2010. Research into pathogenic microorganisms requires three balance to be achieved: investment in BDAP and CEHTP studies; basic and applied research; a faster pace of research into pathogens and fulfilling biosafety and biosecurity requirements.

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In traditional Chinese medicine, plants of the genus Peganum have been used to treat cough, hypertension, diabetes, asthma, jaundice, lumbago, and many other ailments. In this study, seeds of the plants of genus Peganum, including P. harmala Linn., P. multisectum (Maxim) Bobr, P. nigellastrum Bunge, and Peganum variety were collected from different provinces in China. A simple, rapid, and effective thin-layer chromatographic (TLC) fingerprint combined with bioautographic technique has been established for the identification of acetylcholinesterase (AChE) inhibitors from these seeds. The methanol extracts of seeds were separated on silica gel plates with ethyl acetate-methanol-ammonia 10:1.5:0.5 (ν/ν) as mobile phase, and then the plates were inspected under UV 366 nm and visualized by spraying with both Dragendorff’s and vanillin-sulfuric acid reagents as well as by bioautographic assay. Moreover, the limits on AChE inhibitive activity of harmine and harmaline were found to be 0.01 μg, in comparison to that of galanthamine of also 0.01 μg. The TLC fingerprints combined with the bioautographic method could distinguish the seeds of the different species of genus Peganum investigated. Moreover, harmine and harmaline displayed similar AChE inhibition compared to galanthamine.

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Authors: Qian-Tao Jiang, Yu-Ming Wei, Ji-Rui Wang, Ze-Hong Yan and You-Liang Zheng

Xinjiang rice wheat ( Triticum petropavlovskyi Udacz. et Migush, 2n=6x=42, AABBDD) is one of the endemic Chinese wheats, only distributing in Xinjiang and Xizang (Tibet), China. A novel high-molecular-weight (HMW) glutenin subunit gene 1Dx2.1 was isolated and characterized from Xinjiang rice wheat accession Daomai2. The complete open reading frame (ORF) of 1Dx2.1 is 2508 bp, encoding 836 amino acids. The primary structure of 1Dx2.1 consists of three distinct domains, a non-repetitive N-terminal domain with 89 residues, a non-repetitive C-terminal domain with 42 residues and a large central repetitive domain with 684 residues. In the N-terminal of 1Dx2.1, there is an R (arginine) at position 75, whereas there is a Q (glutamine) in other known x-type subunits. Four cysteine residues are observed in 1Dx2.1 with three in the N-terminal region and one in the C-terminal region. The number and distribution of cysteines in 1Dx2.1 are identical to those in x-type subunits except for 1Dx5, which possesses an extra cysteine residue. Differences between the repetitive domain of 1Dx2.1 and those of known HMW subunits resulted from substitutions, insertions or/and deletions involving single or more amino acid residues. The phylogenetic tree, which was constructed on the basis of amino acid sequences, and indicated that 1Dx2.1 was highly related to 1Dx2.1 t , then to 1Dx2 and 1Dx5.

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