Rongji Dai

Chromatographic fingerprint analysis of Cephalotaxus sinensis from various sources by high-performance liquid chromatography-diodearray detection-electrospray ionization-tandem mass spectrometry

Selective and efficient analytical methods are required not only for quality assurance but also for authentication of Chinese herbal medicine. A simple, rapid and valid fingerprint method has been first carried out for the quality control of Cephalotaxus sinensis by using high-performance liquid chromatography (HPLC) coupled with photodiode array detection (DAD) and electrospray ionisation-tandem mass spectrometry (ESI-MS). The characteristic analytical fingerprints of this plant extract showed 18 common peaks, and out of these, 10 compounds involving 2 new compounds were identified by comparing the retention time, UV and ESI-MS/MS spectrum of each standard with those of each peak separated by on-line HPLC-DAD-MS/MS. Moreover, the effects of collecting locations, harvesting time, storage time, drying methods, and medicinal portions on herbal chromatographic fingerprints were examined by similarity analysis and principal component analysis (PCA) along with markers. Using the reference fingerprint along with markers, the best harvesting time, cultivation location and medicinal part were determined. The results obtained suggest that the chromatographic fingerprint combining similarity evaluation and PCA along with markers or pharmacologically active constituents can efficiently identify raw herb of Cephalotaxus sinensis from different sources, which provide helpful clues to the study of plants secondary metabolites and benefit quality control.

Dragon's Blood extract has antithrombotic properties, affecting platelet aggregation functions and anticoagulation activities.

ETHNOPHARMACOLOGICAL RELEVANCE Dragons Blood from Dracaena cochinchinensis (Lour.) S.C. Chen (Yunnan, China), as a traditional Chinese medicinal herb, was shown to have certain antithrombotic effects. A new preparation process was used to extract effective components from Dragons Blood. A 95% ethanol extract A (EA) and a precipitate B (PB) fraction were obtained and compared. Reliability of the preparation process was validated by pharmacodynamic experiments. MATERIALS AND METHODS A rat/mouse thrombosis and blood stasis model was developed for this study, and EA and PB effects on thrombosis, platelet functions and blood coagulation activities were analyzed. RESULTS It was observed that the EA fraction had significantly better inhibitory effects than the PB fraction on thrombosis (p<0.05), platelet aggregation function (p<0.01) and anticoagulation activity (p<0.05-0.01). CONCLUSIONS The results obtained here showed that EA fraction from Dragons Blood contained pharmacologically effective compounds with antithrombotic effects, partially improving platelet function and anticoagulation activity.

Hypoglycemic effect of Belamcanda chinensis leaf extract in normal and STZ-induced diabetic rats and its potential active faction.

Belamcanda chinensis (Iridaceae) belongs to the family of iridaceae and its rhizoma has been widely used for the treatment of throat ailment. Here we report a new pharmacological activity of B. chinensis leaf extract (BCL), that is, the hypoglycemic effect in normal and STZ-induced diabetic rats. Animals either healthy or STZ-induced diabetic show significantly lowered fasting blood glucose levels after treatment with BCL. The serum insulin concentration in normal rats is also enhanced. Additionally, the increase in blood glucose levels after administration of various carbohydrates in normal rats is significantly decreased and the oral glucose tolerance (OGTT) of STZ-induced diabetic rats is largely improved by BCL treatment. However, co-administration of BCL with Nifedipine, a Ca(2+) ion channel blocker, or Nicorandil, an ATP-sensitive K(+) ion channel opener thoroughly abolishes the hypoglycemic effect of BCL. HPLC analysis and compound identification showed that several isoflavone glycosides with antidiabetic activities were contained in BCL while pharmacological experiment showed that the polysaccharide fraction of BCL had no significant hypoglycemic effect on normal rats. Therefore, the isoflavone glycosides but not polysaccharides might be the active fraction of BCL in diabetes treatment.

Appraisal of antinociceptive and anti-inflammatory potential of extract and fractions from the leaves of Torreya grandis Fort Ex. Lindl

Torreya grandis (Taxaceae) was studied for antinociceptive and anti-inflammatory effects. Leaves were extracted with 80% ethanol at 80 degrees C for 3h and fractionated with petroleum ether, chloroform, ethylacetate and n-butanol. The aqueous ethanolic extract (aq.EE), ethylacetate fraction (EaF) and butanol fraction (BtF) at the doses of (100 and 200mg/kg, i.g.) body weight were used for study. Evaluation of antinociceptive activity was carried out by acetic acid-induced writhing response and formalin-induced paw licking time in the first and second phases of mice. The paw edema induced by formalin- and xylene-induced ear edema were used to assess anti-inflammatory activity. It was found that Torreya grandis extract and fractions at the doses of (100 and 200mg/kg, i.g.) were significantly attenuated the writhing responses induced by acetic acid and second phase of pain response induced by subplantar injection of formalin in mice. In addition, these extract and fractions inhibiting the formaldehyde-induced arthritis as well as xylene-induces edema prolifically. From acute oral toxicity studies no mortality was pragmatic even at highest dose (2500 mg/kg, i.g.). Furthermore, our phytochemical studies indicated that the aq. ethanolic extract of leaves contains alkaloids, flavonoids, tannins, terpenoids and saponins. The results provide justification for the folkloric uses of Torreya grandis in the treatment of analgesic and inflammatory-based diseases across the China.

Dragon's blood may have radioprotective effects in radiation-induced rat brain injury.

Dragons blood is a bright red resin obtained from Dracaena cochinchinensis. It is a traditional medicinal that is used for wound healing and to stop bleeding. Its main biological activity appears to be from phenolic compounds found in Dragons blood. In this study, the radioprotective effects of Dragons blood were examined after whole brain irradiation of rats with either 100 MeV/u Carbon 12C6+ heavy ions or 60Co γ-rays. The amounts of radiation-induced oxidative stress, inflammatory cytokines and apoptosis in irradiated rat brains were compared with and without Dragons blood treatment. Compared to the “irradiation only” control group, the Dragons blood treatment group significantly decreased malondialdehyde and hydrogen peroxide levels, and increased superoxide dismutase activity and glutathione levels induced by oxidative stress in radiation exposed rats (P < 0.05). Dragons blood also significantly reduced radiation-induced inflammatory cytokines of tumor necrosis factor-α, interferon-γ and interleukin-6 levels (P < 0.05) and inhibited hippocampal neuronal apoptosis in 60Co γ-ray irradiated rats. Furthermore, Dragons blood significantly increased expression of brain-derived neurophic factor and inhibited the expression of pro-apoptotic caspase 3 (P < 0.05–0.01). Finally, Dragons blood significantly inhibited expression of the AP-1 transcription factor family members c-fos and c-jun proteins (P < 0.05–0.01). The results obtained here suggest that Dragons blood has radioprotective properties in rat brains after both heavy ions and 60Co γ-ray exposure.

Combination of HPLC chromatogram and hypoglycemic effect identifies isoflavones as the principal active fraction of Belamcanda chinensis leaf extract in diabetes treatment.

In previous study, we demonstrated the hypoglycemic effect of aqueous extract of Belamcanda chinensis leaves in rats. Here, we separated the aqueous extract of B. chinensis leaves and investigated the spectrum-effect relationships between HPLC chromatograms and hypoglycemic activities of different isolates from B. chinensis leaf extract. Sequential solvent extraction with petroleum ether, chloroform, acetic ester and n-butanol provided several isolates showing similar hypoglycemic activities, making it difficult to discriminate the active fractions. Stepwise elution through HP20 macroporous resin by water, 40% and 95% ethanol provided isolates with distinct hypoglycemic activities, representing a simple, rapid and efficient preparative separation method. Combination of HPLC chromatogram and pharmacological effect targeted a hypoglycemic activity-related region in HPLC chromatogram. Each peak in this region was analyzed by UV spectrum scan. Most of them were flavonoids in which tectoridin and swertisin were known flavonoids with anti-diabetic activities. In together, this work provides a general model of combination of HPLC chromatography and pharmacological effect to study the spectrum-effect relationships of aqueous extract from B. chinensis leaves, which can be used to find principle components of B. chinensis on pharmacological activity.

Preparation and characterization of temperature-responsive capillary electrochromatographic column using poly(N-isopropylacrylamide).

Poly(N‐isopropylacrylamide) is a temperature‐responsive polymer, which is hydrophilic at low temperature but hydrophobic at high temperature. Using this characteristic, the polymer was bonded to the inner surface of fused‐silica capillary to prepare a temperature‐responsive column to study the separation behavior in electrochromatography.

Study of binding constant of toll-like receptor 4 and lipopolysaccharide using capillary zone electrophoresis.

This short communication describes the interaction between toll‐like receptor 4 (TLR4) and lipopolysaccharide (LPS, its specific ligand) using analytical methods. Their interaction has been evidenced in many reports. Nevertheless, there are few reports focused on their binding constant. In this research, the interaction between TLR4 and LPS is investigated using mobility shift method by CZE. To optimize the electrophoresis conditions, the effecting factors, running buffer, sample concentration, injection duration, and operation voltage of electrophoretic on the mobility shift are studied in detail. Electrophoresis conditions were described as follows: borate buffer (pH 7.4, 20 mM), 5 s for 50 mbar pressure injection duration, and 13 kV of separation voltage in 41.5 cm fused silica capillary with 75 μm id and 375 μm od. The combination constant of TLR4 and LPS is calculated using Scatchard methods. The Scatchard liner correlation is y=−0.0165x+0.1456, binding constant is K=1.65×104 (g/mL)−1.

Synthesis of nitroanilines catalyzed by horseradish peroxidase in the presence of NaNO2 and H2O2

The synthesis of nitroanilines catalyzed by horseradish peroxidase(HRP) in the presence of sodium nitrite and hydrogen peroxide was investigated. o-Nitroaniline and p-nitroaniline were found in the nitrated products. 2-Aminotoluene and 4-aminotoluene could also be nitrated to give corresponding nitrated products. This protocol has great potentials to open new avenues useful for the synthesis of nitroaniline and its derivatives.

Normobaric Hypoxia-induced Brain Damage and Mechanism in Wistar Rat

To evaluate normobaric hypoxia-induced brain damage and discuss the mechanism in wistar rat brain injury, the water content of brain , brain infarction area ratio , the level of lactic acid and Na + -K + -ATPase activity were detected. The expression of HIF-lalpha was confirmed using immunohistochemistry. Histopathological changes of brain in rat model due to hypoxia were investigated using hematoxylin and eosin stain (HE). Results showed that the levels of lactic acid were positively correlated with the degree of hypoxia which caused a concentration-dependent decrease in total Na + -K + - ATPase activity. Compared with the control group, brain water content of rat model had significant difference under serious hypoxia condition. Brain infarction ratio increased sharply when lactic acid level increased and Na + -K + -ATPase activity decreased obviously. Histopathological examination confirmed that there was a necrotic feature in one single hippocampal gyrus neuron cell. HIF-lalpha (hypoxia induced factor-lalpha) was induced by hypoxia at 6% 02. Expression of HIF-lalpha enhanced the hypoxia adaptation capability of the rat model through regulating the expression of multiple genes. Lactic acid, Na + -K + -ATPase and HIF-lalpha played an important role in brain injury as a possible mechanism.