Structure And Anticancer Activity Of Glycoalkaloids

Glycoalkaloids are important natural products, mainly produced by Solanaceae and Liliaceae plants. Great progress has been made in structure, biological activity, toxicity, synergistic action, membrane disruption of glycoalkaloids and their mechanisms of activity and toxicity. But the reports about structure-activity relationship of glycoalkaloids are quite less. In this paper, the relationship of the structure and anti-cancer activity of glycoalkaloids has been studied.At first, α -chaconine and α -solanine were isolated from the seedling of Solarium tuberosum.. The isolated compounds were characterized by TLC and NMR.Further, a series of hydrolysis products of these glycoalkaloids were prepared by acid hydrolysis, then isolated and purified by column chromatography, recrystallization, and the isolated compounds were characterized by TLC and NMR. The results showed that α -chaconine produced four products: β₁, β₂,γ-chaconine and the aglycon solanidine;α -solanine produced three products: β₂, γ-solanine and the aglycon solanidine;α-solamargine produced four products: β₁, β₂,γ-solamargine and the aglycon solasodine;α-solasonine produced three products: β-2, γ-solasonine and the aglycon solasodine.The inhibition of α -solamargine and α -solasonine and their hydrolysis products to HCT tumor cells was determined by MTT assay. The results showed that α -solamargine, α -solasonine, β₁-solamargine and the aglycon solasodine were active in the assay. Their effects were concentration dependent in the range of 1-40 μM and the IC50 were 11.97, 10.48, 27.65 , 29.82μM respectively. The other four hydrolysis products: β₂, γ-solamargine and β₂, γ-solasonine did not exhibit anticancer activity in the range of 0.5⁴0μM. The untouched glycoalkaloids were the most active and the hydrolysis products less so. These results indicated that carbohydrate side chains of the glycoalkaloids were paramount in influencing biological activity. Not only the number but also the type of carbohydrate, as well as the order of attachment affected the anticancer activity of the glycoalkaloids, at the same time, the aglycon solasodine had important role in their anticancer activity.