Antiemetic activity of effective extract and bioactive compounds in ginger / 中国中药杂志

To investigate the antiemetic effect of the active extract (ginger ether extract, GEE) and its bioactive compounds in ginger, the pica vomiting model in rats and the gastric emptying model in mice were used to observe the antiemetic effect of GEE in cisplatin-induced pica and gastric emptying, and the main components in GEE were detected by RP-HPLC; in vitro, the antagonist effect of GEE and the four components in it were explored by the contraction of guinea-pig ileum induced by SR57227A and carbachol. The results showed that the amount of Kaolin ingested by rats were declined significantly in all the three groups of GEE (25,50,100 mg•kg⁻¹) (P<0.01), while cisplatin-induced gastric emptying in mice was also suppressed in all the three groups (P<0.01), and 6-gingerol, 8-gingerol,10-gingerol and 6-shogaol were found mainly in GEE by RP-HPLC; the maximum contraction of isolated guinea-pig ileum could be reduced by addition of GEE (2.3, 4.6, 11.5 mg•L⁻¹), 6-gingerol,8-gingerol,10-gingerol or 6-shogaol (1, 2, 5 μmol•L⁻¹) when the concentration of SR5727A was 1×10⁻⁵ mol•L⁻¹ and that of carbachol was 1×10⁻⁴ mol•L⁻¹ (P<0.05, P<0.01). In conclusion, 5-HT3 and M3 receptors could be antagonized by GEE and its bioactive compounds 6-gingerol, 8-gingerol, 10-gingerol and 6-shogaol, which may be correlated with the antiemetic mechanism of ginger maybe related to it.

Mechanistic study of ozonation of p-nitrophenol in aqueous solution.

Ozonlysis in the treatment of p-nitrophenol solution was studied in this paper. The results indicated that the decomposition of p-nitrophenol was accelerated as the gas flow rate or pH value increased. When gaseous ozone concentration was 20.11 mg/L and pH was 3, after 24 min reaction, the removal rate of p-nitrophenol reached 73.04%, 86.11%, 91.71% and 95% at the gas flow rate of 32, 40, 48 and 56 ml/min respectively. And when pH was 3, 4, 5, 6, the decomposition rate was 66.38%, 82.09%, 90.46%, 97.50% after a 20 min reaction respectively. It was mainly O3 molecule that took part in the decomposition when pH was 3. The main intermediates during the decomposition include catechol, o-benzoquinone, hydroquinone, p-benzoquinone, phenol, fumaric acid, maleic acid, oxalic acid and formic acid. The decomposition mechanism of p-nitrophenol was also discussed.