Insights into the Biosynthesis of Caffeoylquinic Acids in Uncaria tomentosa Root Cultures

The DNA repair action of Uncaria tomentosa has been attributed to chlorogenic acid and 3,4-di-O-caffeoylquinic acid present in the bark and roots of the plant. Extractive harvesting of the species has compromised its survival in natural environments. Thus, establishing in vitro root production and investigating the biosynthetic pathway of these compounds could make their production sustainable. In this context, an in vitro growth curve of U. tomentosa roots was established in culture medium supplemented with glucose and 5.37 μM 1-naphthaleneacetic acid. Subsequently, the root culture was grown in 1-13C-glucose. Production of labeled chlorogenic acid and 3,4-di-O-caffeoylquinic acid was confirmed by spectroscopic methods, and their contents were determined by HPLC. U. tomentosa root cultures produced 2.03 mg·g−1 dry weight (DW) of chlorogenic acid at 27 days of cultivation and 3.44 mg·g−1 DW of 3,4-di-O-caffeoylquinic acid at day 18. These compounds were isotopically labeled, exhibiting an incorporation pattern consistent with the shikimate pathway. The established U. tomentosa root culture represents a promising biotechnological platform for obtaining these compounds.