Extraction of berberine and removal of cadmium from Coptis chinensis Franch.

The organic solvents refluxing was used to extract berberine from Coptis chinensis Franch.,and the extraction condition,including concentration of ethanol,extraction temperature,solid-liquid ratio were chosen as indices in the extraction process by the response surface method.In the same time,atomic absorption spectrophotometry was employed to test the contents of cadmium and berberine in Coptis chinensis Franch.after removal of cadmium with different treatments.The results showed that the best conditions for extraction berberine were using 53% ethanol,extraction at 62℃,with solid/solvent ratio of 1:11,extraction for 1 h and two times.The best treatment was using 3% ammonia for extracting six hours plus 3% NH4NO3 for six hours,and the content of cadmium is 0.0376 mg?kg-1,less than 0.3 mg/kg,which meets the pharmacopoeia standards(2010 edition).The content of berberine is 8.0%.