Optimisation of steam distillation extraction oil from onion by response surface methodology and its chemical composition.

Oil extraction from onion was performed by steam distillation. Response surface methodology was applied to evaluate the effects of ratio of water to raw material, extraction time, zymolysis temperature and distillation times on yield of onion oil. The maximum extraction yield (1.779%) was obtained as following conditions: ratio of water to raw material was 1, extraction time was 2.5 h, zymolysis temperature was 36° and distillation time was 2.6 h. The experimental values agreed well with those predicted by regression model. The chemical composition of extracted onion oil under the optimum conditions was analysed by gas chromatography-mass spectrometry technology. The results showed that sulphur compounds, like alkanes, sulphide, alkenes, ester and alcohol, were the major components of onion oil.

In vivo biodistribution, anti-inflammatory, and hepatoprotective effects of liver targeting dexamethasone acetate loaded nanostructured lipid carrier system.

We aimed to evaluate whether the enhancement of the liver accumulation and anti-inflammatory activity of dexamethasone acetate (DXMA) could be achieved by incorporating it into nanostructured lipid carrier (NLCs). DXMA-NLCs were prepared using a film dispersion-ultrasonication method and characterized in terms of particle size, PDI, zeta potential, differential scanning calorimetry, drug loading capacity, encapsulation efficiency, and in vitro release. The biodistribution and pharmacokinetics of DXMA-NLCs in mice were significantly different from those of the DXMA solution (DXMA-sol). The peak concentration of DXMA-NLCs was obtained half an hour after intravenous administration. More than 55.62% of the total administrated dose was present in the liver. An increase of 2.57 fold in the area under the curve was achieved when compared with that of DXMA-sol. DXMA-NLCs exhibited a significant anti-inflammatory and hepatoprotective effect on carrageenan-induced rats and carbon tetrachloride-induced mice compared with DXMA-sol. However, the effect was not in proportion to the dosage. The intermediate and low dosages presented better effects than DXMA-sol. All results indicate that NLCs, as a novel carrier for DXMA, has potential for the treatment of liver diseases, increasing the cure efficiency and decreasing the side effects on other tissues.

[Study on beta-amyloid peptide 1-42 induced chemokine RANTES in U251 cell].

OBJECTIVE: To study the molecular mechanisms of beta-amyloid 1-42 (Abeta1.42) induced the inflammatory response in U251 cells. METHODS: U251 cells were treated with different concentration of Abeta1-42 (0.2-4.0 micromol/L) for 24 h, and the cell survival rate was evaluated by MTT. After treated with 2.0 micromol/L Abeta1-42 for 12, 24, 36, 48 hours, the nitric oxide content of U251 cells were detected with nitrate reductase method. The RANTES expression was tested by dual-antibody sandwich ELISA method. The expression of NF-kappaB and STAT1 were detected by the immunocytochemical staining. RESULTS: Abeta1-42 decreased the survival rate of U251 cells in dose-dependent manner. The NO generated in 2 micromol/L Abeta1-42 treated U251 cells reached its peak at 24 h and gradually decreased thereafter. The expression of RANTES increased 4-fold (P < 0.01). The NF-kappaB P65, the STAT1 moved from the cytoplasm to the nucleus and expressed significantly were also observed in the 2 micromol/L Abeta1-42 treated U251 cells. CONCLUSION: Abeta1-42 decreases the survival rate of U251 cells and induce the releasing of NO and RANTES. This indicates that Abeta1-42 induced chemokine RANTES in U251 cell may be close related to the activation of NF-kappa B and STAT1.