Effect of Alkaloid-Free and Alkaloid-Rich preparations from Uncaria tomentosa bark on mitotic activity and chromosome morphology evaluated by Allium Test.

Ethnopharmacological Relevance: Uncaria tomentosa (Willd.) DC. is the most popular Peruvian plant, used in folk medicine for different purposes. It contains thousands of active compounds with great content of alkaloids.

Aim Of Study: Two different fractions of Alkaloid-Rich and Alkaloid-Free were researched on chromosome morphology, mitotic activity and phases indexes.

Materials And Methods: Cells of Allium Test (meristematic cells of root tips) were incubated up to 24h in different concentrations of Alkaloid-Free and Alkaloid-Rich fraction obtained from Uncaria tomentosa bark followed by 48 h of postincubation in water. The chromosome morphology was analyzed and the content of mitotic and phase indexes were done. Individual compounds, oxindole alkaloids, phenolic compounds and sugars were determined.

Results: In Alkaloid-Rich and Alkaloid-Free fractions (different in chemical composition) we observed condensation and contraction of chromosomes (more in Alkaloid-Rich) with retardation and/or inhibition of mitoses and changed mitotic phases. Postincubation reversed results in the highest concentration which was lethal (in mostly Alkaloid-Rich fraction).

Conclusions: Our studies indicate that different action can depend on different groups of active compounds in a preparation either containing alkaloids or not. Other fraction analysis may be useful in the future.