Objective: To study and approach the processing methods and mechanism which can markedly reduce the content of aristolochic acid in Aristolochia manshuriensis and lighten the nephrotoxicity of aristolochic acid.
Methods: A traditional "attenuation" processing method was used and 30 types of samples which contain one crude and 29 types of processed sample were obtained. The contents of aristolochic acid A in every sample were determined by HPLC. According to the Rat's acute renal injury test, the influence of animal's renal function was investigated for representative samples.
Results: The content of aristolochic acid in six types of samples depressed markedly (30% or more depressed) which processing with boiling in the limewater, steaming with limewater, boiling in the juice of liquorice, boiling in the decoction of black soybean, boiling in the soda water and stir-baked with talcum powder, the content of aristolochic acid in other processed samples also depressed with a large discrepancy. The toxicology test results showed that the above-mentioned 6 samples all can relieve renal injury of rats. There could be some associativity between the degree of renal injury relieving and the content of aristolochic acid A in the samples.
Conclusion: The content of aristolochic acid can be reduced and the nephrotoxicity for animals can be lightened with some eligible processing methods for the traditional Chinese medicines containing aristolochic acid with the representative of Aristolochia manshuriensis.