Effect of starch composition on dissolution of alkaloids in Aconiti Radix co-decocted with Pinelliae Rhizoma or Ampelopsis Radix / 中草药

ABSTRACT

Objective: To analyze the effect of starch composition on the dissolution of small molecular alkaloids in Aconiti Radix when co-decocted with medicines rich in starch, and to explore the mechanism of the effect of starch on alkaloids. Methods: RRLC-Q- TOF-MS was used to analyze the effect of starch on the dissolution of alkaloids in the decoctions. HPLC-UV was applied to determine the content of alkaloids in the decoctions of starches with alkaloids, and analysis of variance and partial least square method were used to analyse the difference. Results: The dissolution of alkaloids in Aconiti Radix, including the diester-, monoester-, and amine- diterpenoid alkaloids, wsa obviously decreased when co-decocted with starch, especially the monoester- and amine-diterpenoid alkaloids co-decocted with Pinelliae Rhizoma, Ampelopsis Radix, starch of Pinelliae Rhizoma, starch of Ampelopsis Radix, and normally sold starch, while the content of diester-diterpenoid alkaloids was increased when co-decocted with starch-removed Pinelliae Rhizoma and Ampelopsis Radix. When co-decocted directly with starch, free alkaloids in water decoction was decreased compared with the decoction without starch. Conclusion: Starch could inhibit the dissolution of alkaloids in Aconiti Radix in the decoction. Free Aconitum alkaloids could be integrated by the starch, which could finally affect their content in decoction.