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Summary

A simple hydrolysis method has been developed for determination of phenylethanoid glycosides in Lamiophlomis rotata (L.R.). Different kinds of phenylethanoid glycosides were hydrolyzed in hydrochloric acid solution to produce corresponding phenethyl alcohols and cinnamic acids, mainly containing hydroxytyrosol, homovanillyl alcohol, 3,4-dimethoxyphenethyl alcohol, caffeic acid, fumalic acid and 3,4-dimethoxycinnamic acid. The six analytes could be determined simultaneously by high-performance liquid chromatography (HPLC). The effects of mobile phase, pH and concentration of running buffer, detection wavelength, flow rate and injection volume were also investigated. Under the optimum conditions, the six hydrolyzates could be perfectly separated within 45 min. The response was linear over four orders of magnitude with detection limits (S/N = 3) ranging from 1 × 10−8 to 1.5 × 10−4 mol L−1 for the analytes. The method has been successfully applied to the analysis of real sample Du-Yi-Wei capsule and Qi-Zheng-Yan-Tong patch, with satisfactory results.

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The forward and reverse cDNA subtractive libraries before and after the toxic effect of α-amanitin were constructed by suppression subtractive hybridization and randomly selected clones from each subtractive library were screened by PCR and dot blot hybridization. A total of 85 genes with altered expression were finally identified, with 41 genes from the forward library and 44 from the reverse library. Subsequently, the antagonistic effects of candidate traditional Chinese medicines were evaluated based on the genetic transcription levels of the genes with significant altered expression, including Catnβ, Flt3-L, IL-7r and Rpo2-4. The results indicated that Silybum marianum (L.) Gaert and Ganoderma lucidum had significant down-regulated effects on the transcription level of Catnβ that was up-regulated by α-amanitin, and the two herbs also up-regulated the transcription levels of Flt3-L and Rpo2-4. Silybum marianum (L.) had significant up-regulated effects on the IL-7r that was down-regulated by α-amanitin. These preliminary studies suggested that Silybum marianum (L.) and Ganoderma lucidum were effective antagonists against the toxicity of α-amanitin.

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Aegilops sharonensis (Sharon goatgrass) is a valuable source of novel high molecular weight glutenin subunits, resistance to wheat rust, powdery mildew, and insect pests. In this study, we successfully hybridized Ae. sharonensis as the pollen parent to common wheat and obtained backcross derivatives. F1 intergeneric hybrids were verified using morphological observation and cytological and molecular analyses. The phenotypes of the hybrid plants were intermediate between Ae. sharonensis and common wheat. Observations of mitosis in root tip cells and meiosis in pollen mother cells revealed that the F1 hybrids possessed 28 chromosomes. Chromosome pairing at metaphase I of the pollen mother cells in the F1 hybrid plants was low, and the meiotic configuration was 25.94 I + 1.03 II (rod). Two pairs of primers were screened out from 150 simple sequence repeat markers, and primer WMC634 was used to identified the presence of the genome of Ae. sharonensis. Sequencing results showed that the F1 hybrids contained the Ssh genome of Ae. sharonensis. The sodium dodecyl sulfate polyacrylamide gel electrophoresis profile showed that the alien high molecular weight glutenin subunits of Ae. sharonensis were transferred into the F1 and backcross derivatives. The new wheat-Ae. sharonensis derivatives that we have produced will be valuable for increasing resistance to various diseases of wheat and for improving the quality of bread wheat.

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Abstract

As N-2′,4′-dinitrophenyl-3,3-dinitroazetidine (DNPDNAZ) is an important derivative of 3,3-dinitroazetidine, its thermal behavior was studied under 0.1 and 2 MPa by the differential scanning calorimetry (DSC) method. The results of this study show that there are one melting process and two exothermic decomposition processes. Its kinetic parameters of the intense exothermic decomposition process were obtained from the analysis of the DSC curves. The activation energy and the mechanism function under 0.1 MPa are 167.26 kJ mol−1 and f(α) = 3(1 + α)2/3[(1 + α)1/3− 1]−1/2, respectively, and the said parameters under 2 MPa are 169.30 kJ mol−1 and f(α) = 3(1 + α)2/3[(1 + α)1/3− 1]−1/2, respectively. The specific heat capacity of DNPDNAZ was determined using a continuous C p mode of micro-calorimeter. Using the relationship between C p and T with the thermal decomposition parameters, the time of the thermal decomposition from initialization to thermal explosion (adiabatic time-to-explosion, t TIAD), the self-accelerating decomposition temperature (T SADT), thermal ignition temperature (T TIT), critical temperatures of thermal explosion (T b), and half-life (t 1/2) were obtained to evaluate its thermal safety under different pressures.

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The objective of this work was to research the antibacterial effects of orange pigment, which was separated from Monascus pigments, against Staphylococcus aureus. The increase of the diameter of inhibition zone treated with orange pigment indicated that orange pigment had remarkable antibacterial activities against S. aureus. Orange pigment (10 mg ml−1) had a strong destructive effect on the membrane and structure of S. aureus by the analysis of scanning electron microscopy as well as transmission electron microscopy. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) further demonstrated that the cell membrane was seriously damaged by orange pigment, which resulted in the leakage of protein from S. aureus cells. A significant decrease in the synthesis of DNA was also seen in S. aureus cells exposed to 10 mg ml−1 orange pigment. All in all, orange pigment showed excellent antibacterial effects against S. aureus.

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To study the development of starch granules in polyploid wheats, we investigated the expression of starch synthetic genes between the synthetic hexaploid wheat SHW-L1, its parents T. turgidum AS2255 and diploid Ae. tauschii AS60. The synthetic hexaploid wheat SHW-L1 showed significantly higher starch content and grain weight than its parents. Scanning electron microscopy (SEM) showed that SHW-L1 rapidly developed starch granules than AS2255 and AS60. The amount of B-type granule in AS60 was less than that in SHW-L1 and AS2255. RT-qPCR result showed that the starch synthetic genes AGPLSU1, AGPLSU2, AGPSSU1, AGPSSU2, GBSSI, SSIII, PHO1 and PHO2 expressed at earlier stages with larger quantity in SHW-L1 than in its parents during wheat grain development. The expression of the above mentioned genes in AS60 was slower than in SHW-L1 and AS2255. The expression pattern of starch synthase genes was also associated with the grain weight and starch content in all three genotypes. The results suggested that the synthetic hexaploid wheat inherited the pattern of starch granule development and starch synthase gene expression from tetraploid parent. The results suggest that tetraploid wheat could plays more important role for starch quality improvement in hexaploid wheat.

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A high-speed counter-current chromatography (HSCCC) method was established for the isolation and purification of isochlorogenic acid A from Lonicera japonica Thunb. The two-phase solvent system was composed of n-hexane:ethyl acetate: isopropanol:water (2:3:2:5, v/v/v/v). From 150 mg of the ethyl acetate fraction of L. japonica Thunb, 19.65 mg of isochlorogenic acid A was obtained in a one-step HSCCC separation, with a purity of 99.1%, as determined by high-performance liquid chromatography (HPLC). The structure was further identified by ultraviolet (UV), mass spectrometry (MS) and nuclear magnetic resonance (NMR).

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Citri Grandis Exocarpium (CGE) is a traditional Chinese medicine with a variety of biological activities. For efficient quality control of CGE, a simple, rapid, and accurate high-performance liquid chromatographic (HPLC) method was developed for simultaneous determination of four main compounds (naringin, rhoifolin, meranzin hydrate, and isoimperatorin) in this herb. These four compounds were separated on a C18 column by gradient elution with methanol and water. The flow rate was 1.0 mL·min−1, and the detection wavelength was 324 nm. The recoveries of the method ranged from 96.32% to 103.71%, and good linear relationships (r 2 > 0.9998) over relative wide concentration ranges were obtained. Then this validated method was successfully applied to the analysis of nine batches of CGE samples.

Open access
Cereal Research Communications
Authors: H.Q. Zhao, L. Wang, J. Hong, X.Y. Zhao, X.H. Yu, L. Sheng, C.Z. Hang, Y. Zhao, A.A. Lin, W.H. Si, and F.S. Hong

Salt stress impaired Mn imbalance and resulted in accumulation of ROS, and caused oxidative stress to plants. However, very little is known about the oxidative damage of maize roots caused by exposure to a combination of both salt stress and Mn deprivation. Thus the main aim of this study was to determine the effects of a combination of salt stress and Mn deprivation on antioxidative defense system in maize roots. Maize plants were cultivated in Hoagland’s media. They were subjected to 80 mM NaCl administered in the Mn-present Hoagland’s or Mn-deficient Hoagland’s media for 14 days. The findings indicated that the growth and root activity of maize seedlings cultivated in a combination of both salt stress and Mn deprivation were significantly inhibited; the compatible solute accumulation, malondialdehyde, carbonyl, 8-OHdG, and ROS were higher than those of the individual salt stress or Mn deprivation as expected. Nevertheless, the antioxidative enzymes such as superoxide dismutase, ascorbate peroxidase, glutathione reductase, glutathione-S-transferase and antioxidants such as ascorbic acid, glutathione and thiol were lower than those of the individual salt stress or Mn deprivation. In view of the fact that salt stress impaired Mn nutrition of maize seedlings, the findings suggested that Mn deprivation at the cellular level may be a contributory factor to salt-induced oxidative stress and related oxidative damage of maize roots.

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Abstract

3,3-Dinitroazetidinium (DNAZ) salt of perchloric acid (DNAZ·HClO4) was prepared, it was characterized by the elemental analysis, IR, NMR, and a X-ray diffractometer. The thermal behavior and decomposition reaction kinetics of DNAZ·HClO4 were investigated under a non-isothermal condition by DSC and TG/DTG techniques. The results show that the thermal decomposition process of DNAZ·HClO4 has two mass loss stages. The kinetic model function in differential form, the value of apparent activation energy (E a) and pre-exponential factor (A) of the exothermic decomposition reaction of DNAZ·HClO4 are f(α) = (1 − α)−1/2, 156.47 kJ mol−1, and 1015.12 s−1, respectively. The critical temperature of thermal explosion is 188.5 °C. The values of ΔS , ΔH , and ΔG of this reaction are 42.26 J mol−1 K−1, 154.44 kJ mol−1, and 135.42 kJ mol−1, respectively. The specific heat capacity of DNAZ·HClO4 was determined with a continuous C p mode of microcalorimeter. Using the relationship between C p and T and the thermal decomposition parameters, the time of the thermal decomposition from initiation to thermal explosion (adiabatic time-to-explosion) was evaluated as 14.2 s.

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