Comparison of Antioxidant Activity and Main Active Compounds Among Different Parts of Alpinia officinarum Hance Using High-Performance Thin Layer Chromatography-Bioautography.

Background: Alpinia officinarum Hance (ginger family) is an important Chinese medicine, especially in Southern China. Objective: A simple and effective high-performance thin-layer chromatography coupled with 2, 2-diphenyl-1-picrylhydrazyl bioautography (HPTLC-DPPH) and electrospray ionization quadrupole time-of-flight tandem mass spectrometry (ESI-Q-TOF-MS/MS) method was developed for the bioactivity-based quality control of A. officinarum. Methods: The HPTLC-DPPH and ESI-Q-TOF-MS/MS were applied for the analysis of different parts of A. officinarum after using methanol extraction for 23 batches of taproot, four batches of aerial, and three batches of fibril parts. Results: The systematic evaluation showed that similar components in taproot and aerial parts make the major antioxidant activity. However, based on our evaluation, the antioxidant ability of the aerial parts is lower than the taproot parts. There is also a significant difference (P < 0.05) between taproot and fibril parts of the root. The chemical structures of compounds with the antioxidant capacity were tentatively identified as 5R-hydroxy-7-(4-hydroxy-3-methoxyphenyl)-1-phenyl-3-heptanone (band 1), kaempferide (band 2), and galangin (band 3) based on ESI-Q-TOF-MS/MS analytical results and further confirmed by standards. Conclusions: This identification indicated that two flavonoid compounds and one diarylheptanoid compound possessed high potentials to be used as the antioxidant biomarkers for the quality control of A. officinarum. Highlights: The comparison of different parts could be considered as guidelines for the usage of A. officinarum.

[Effects of echinacoside on extracellular acetylcholine and choline levels of hippocampus and striatum of cerebral ischemia rats].

The aim of this study is to investigate the effect of echinacoside (ECH) on cholinergic neurotransmitter extracellular of hippocampus and striatum and its possible mechanisms of neuro-protective effect against vascular dementia rats. In this study brain microdialysis technique combined with HPLC-IMER-ECD (high-performance liquid chromatography-immobilized enzyme reactor-electrochemical detector) was used. The bilateral common carotid arteries occluded in two times operation at 72 h interval for vascular dementia model rats were used and the successful vascular dementia model rats were examined by Morris water maze. The content of acetylcholine (ACh) and choline (Ch) of microdialysate extracellular of hippocampus and striatum was determined by HPLC-IMER-ECD and the AChE activity in the hippocampus was measured. The results showed that the success rate of vascular dementia model was 83.08% after six weeks; the results also showed that echinacoside and galantamine could increase the content of ACh and reduce the content of Ch extracellular of hippocampus and striatum significantly and the AChE activity increased significantly compared with that of the model group. The results suggested that echinacoside could promote the recovery of cholinergic neurotransmitter levels in vascular dementia rats' brain, which may be one of the mechanisms of neuro-protection.

[Structure and luminescence properties of MgGa2O4 : Cr3+ with Zn substituted for Mg].

A series of red long afterglow phosphors with composition Zn(x) Mg(1-2) Ga2 O4 : Cr3+ (x = 0, 0.2, 0.6, 0.8, 1.0) were synthesized by a high temperature solid-state reaction method. The X-ray diffraction studies show that the phase of the phosphors is face-centered cubic structure. Photoluminescence spectra show that the red emission of Cr3+ originated from the transition of 2E-4A2. Due to the large overlap between absorption band of Cr3+ and emission band of the host. Cr3+ could obtain the excitation energy from the host via the effective energy transfer. The afterglow decay characteristics show that the phosphor samples with different Zn contents have different afterglow time and the afterglow time also changes with the value of x. The measurement of thermoluminescence reveals that the trap depth of the phosphor samples with different Zn contents is different. The samples with deeper traps have longer afterglow time.