The study aimed to investigate the effect of processing on lectin protein in four toxic Chinese medicines tubers of Pinellia ternata,P. pedatisecta,Arisema heterophyllum and Typhonium giganteum. Western blot was used to semi-quantitatively analyze the content of lectin in the four kinds of toxic Chinese medicines and their different processed products. Raw products and lectin were treated by heating or soaking in ginger juice or alum solution. The effects of different excipients and the heating methods on lectin proteins were investigated. The results showed that the content of lectin in raw products of P. pedatisecta,P. ternata,A. heterophyllum,and T. giganteum were 7. 3%,4. 9%,2. 7%,2. 3%,respectively. And the content of lectin in Pinelliae Rhizoma praeparatum cum alumine was 0. 027%. Lectin was not detected in the Pinelliae Rhizoma Praeparatum cum Zingibere et Alumine,Arisaematis Rhizma Praeparatum and Typhonii Rhizoma Praeparatum,which indicated that processing could significantly reduce the content of active lectin in raw products. The results also showed that with the prolongation of soaking and heating time,the content of lectin in raw products decreased gradually,while the content was almost unchanged when soaked in ginger juice alone. The effects of different excipients and heating on lectin were the same as those on raw products. Therefore,the method with alum soaking and heating can reduce the content of active lectin,which is the key to reduce the toxicity of toxic Chinese medicines. In this paper,Western blot was used to study the content of toxic protein in Araceae toxic Chinese medicines as an evaluation method of the processing degree.
Keywords: Araceae; lectin; processing; toxic component.