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  • Author or Editor: G. Zhang x
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Summary

Radix Isatidis has widely useful activities including anti-virus, anti-bacterial. Tryptanthrin, indigo, and indirubin are active ingredients in R. Isatidis. Response surface methodology (RSM)-optimized infrared-assisted extraction (IRAE) was developed and combined with HPLC for simultaneous determination of tryptanthrin, indigo, and indirubin from R. Isatidis. IRAE were investigated through extraction yields of the three components and optimized by RSM. The optimum conditions were as follows: infrared power of 129 W, solid/liquid ratio of 1:40 g/mL, and irradiation time of 22.5 min. IRAE conditions obtained by RSM were not only accurate, but also had practical value reflecting the expected optimization. Subsequently, this novel IRAE method was evaluated by extraction yield of the components of R. Isatidis samples from different regions. Compared with common extraction methods including maceration extraction (ME), reflux extraction (RE), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE), IRAE showed higher yield with advantages of no limitation of solvent selection, low cost, convenience under optimum extraction conditions. These results suggested the potential of RSM-optimized IRAE for extraction and analysis of the water-/fat-soluble compositions of Chinese herbal medicine. A simple chromatographic separation for simultaneous determination of tryptanthrin, indigo, and indirubin from Chinese herbal medicine R. Isatidis was performed on a C18 column (Diamonsil 150 mm × 4.6 mm i.d., 5 μm) with a mobile phase isocratic consisting of methanol and water at a flow-rate of 0.8 mL min−1. The retention times of tryptanthrin, indigo, and indirubin were 15.4, 31.9, and 58.6 min, respectively. The linear equations were obtained as follows: y = −3094.5744 + 21208.792x for tryptanthrin (R = 0.9998, 0.9–18.0 μg mL−1), y = 4730.0448 + 30180.567x for indigo (R = 0.9997, 0.5–10.0 μg mL−1) and y = −6582.9045 + 67069.312x for indirubin (R = 0.9997, 0.4–8.0 μg mL−1). The result showed that RSM-optimized IRAE was a simple, efficient pretreatment method for the analysis of complex matrix.

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This paper reports the study of hydrogen and carbon monoxide produced by radiation degradation of N, N-dimethylhydroxylamine (DMHA). The results show that when the concentration of DMHA is between 0.1M–0.5M and the dose is between 10–1000 kGy, the volume fraction of hydrogen is very high and increases with the dose. The volume fraction of hydrogen is little dependent on the concentration of DMHA at lower dose but increases with increasing concentration of DMHA at higher dose. The volume fraction of carbon monoxide is very low.

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This paper reports on the qualitative and quantitative analyses of light hydrocarbons produced by radiation degradation of N,N-diethylhydroxylamine. The results show that when the absorbed doses are between 10 and 1000 kGy, the main light hydrocarbons are methane, ethane, ethene, propane and n-butane. Their volume fractions are increased with the increase of the dose. The volume fraction of ethene is also increased at low doses with the increase of the dose, but it is decreased with the increase of dose at high doses.

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Nuclear microprobe was used to measure single aerosol particles (SAPs) indoors from Shanghai. Every particle is characterized with its micro-PIXE spectrum, which can be considered as the fingerprint of the SAPs. The pattern recognition technique (PR) was applied to trace the SAPs back to their source. Results of five monitor homes at different locations in Shanghai show that most of the measured indoor aerosol particles are derived from soil dust, cement dust, vehicle exhaust, coal boilers and steel mill dust.

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1,7-Dihydroxy-3,8-dimethoxyxanthone (X1) and 1,8-dihydroxy-3,7-dimethoxyxanthone (X2) are two important xanthones of the Tibetan medicinal plant Gentianopsis paludosa (Hook. f.) Ma. They are very similar in structure, the only difference being exchange of OH and OCH3 at the 7 and 8 positions. By calculations based on the geometry of the molecules using the MM+ force field, the different distances between the hydroxyl groups of the two xanthones were obtained (4.64774 Å for X2 and 7.19412 Å for X1), therefore, the two hydroxyl groups of X1 should freely interact with more water molecules than those of X2 in aqueous solution. In other words, X2 is more hydrophobic than X1. Micellar electrokinetic capillary chromatography (MEKC) was therefore chosen for separation of the compounds. The optimum separation conditions were: 20 mm borate + 20 mm SDS (pH 9.8) as running buffer, 17.5 kV applied potential, and detection wavelength 260 nm. The two xanthones were well separated in 9.0 min, with Gaussian peak shapes. The repeatability of the MEKC method (expressed as RSD) for X1 and X2 was 0.9 and 1.1%, respectively, for migration time, and 3.1 and 1.4% for peak area. The limits of detection (S/N = 3) were 0.41 μg mL−1 for X1 and 0.82 μg mL−1 for X2. The recovery of the MEKC method for the two xanthones was also satisfactory.

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The effects of sowing date, nitrogen application level and timing on barley protein components and malt quality were investigated. There was a significant difference in total protein and its protein fractions among the four barley genotypes. The protein component was changeable over the different growing conditions, and the extent of change varied with protein fraction and genotype. Marked variation in malt quality over the different environments (sowing date, N fertilizer rate and applying time) was also observed. Increased N fertilizer application increased diastatic power (DP) value, but reduced malt extract. Grain protein content was significantly and positively correlated with albumin, globulin and hordein, but was not correlated with glutelin. However, glutelin was significantly related to other malt quality parameters.

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99Tc is an important radionuclides related to repository safety assessment. The mobility pertechnetate (TcO4 ) can be reduced to immobility technetium(IV) hydrous oxides (TcO2·nH2O) by Fe(II)-bearing minerals. In China, Gaomiaozi (GMZ) bentonite is regarded as the favorable candidate backfilling material for the HLW repository, which is contained some FeO. The diffusion behavior of 99Tc was investigated in GMZ bentonite by through- and out-diffusion methods. The effective diffusion coefficient (D e), the accessible porosity (εacc), apparent diffusion coefficient (D a) and distribution coefficient (K d) were decreased with the increasing of dry density. The D e values were (2.8 ± 0.2) × 10−11 m2/s and (3.5 ± 0.2) × 10−12 m2/s at dry density of 1,600 and 1,800 kg/m3, respectively. It was indicated that the dominating species was TcO4 during the diffusion processing. While, out-diffusion results showed that part of TcO4 may be reduced by Fe(II). The relationship of D e and εacc could be described by Archie’s law with exponent n = 2.4 for 99Tc diffusion in GMZ bentonite. Furthermore, the relationship between D a and dry density (ρ) was exponential.

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Rye (Secale cereale) plays an important role in wheat improvement. Here we report a new triticale, named Fenzhi-1, derived from the wide cross MY11 (Triticum aestivum) × Jingzhou (Secale cereale) after the in vitro rye pollen has been irradiated by He-Ne laser. Morphologically, Fenzhi-1 is characterized by branched-spikes. Genetically, Fenzhi-1 displays stable fertility and immunity to wheat powdery mildew and stripe rust. In situ hybridization (FISH) and seed storage protein electrophoresis revealed that Fenzhi-1 is a new primary hexaploid triticale (AABBRR). The present study not only provides a new method to synthesize an artificial species, but also shows that Fenzhi-1 could be a valuable source for wheat improvement.

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Two peptide ligands conjugated adenine, [9-N-(tritylmercapto acetyl diglycyl aminoethyl) adenine, Tr-MAG2-Ade] and [9-N-(tritylmercapto acetyl triglycyl aminoethyl) adenine, Tr-MAG3-Ade], are synthesized and labeled with 99mTc by directly labeling method. The stability of 99mTc-MAG2-adenine and 99mTc-MAG3-adenine in vitro is measured. The uptake radios of tumor to muscle at 3h post-injection are 5.70 and 4.92, respectively. The biodistribution and scintigraphic imaging studies show that the two complexes have high localization in tumor and high contrasted tumor images can be obtained, which suggest their potential utility as tumor imaging agents. But the high radioactivity of abdomen could prevent the tumor imaging in this area.

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