Free diterpenes cafestol and kahweol in beans and in vitro cultures of Coffea species.

Caffeine and chlorogenic acids are the major bioactive metabolites in beans of coffee, which also contains the unique diterpene compounds cafestol and kahweol known to be responsible for hypercholesterolemic effects in humans. The aim of the study was to profile cafestol and kahweol in different plant parts of Coffea species and its beans grown in India, and also in in vitro raised tissues of commercial Indian species, viz. Coffea arabica and Coffea canephora. Total quantities of free diterpene levels were found to be comparatively higher in beans of C. arabica (1.89 mg g–1) than in C. canephora (1.13 mg g–1). Other plant parts, except the roots, showed considerable amount of cafestol and kahweol. These diterpenes were also synthesized in somatic embryos and in vitro regenerated plants of both Coffea species. Somatic embryos of C. canephora and C. arabica subjected to different hormonal treatments showed variation in the levels of total diterpenes. In this study, we were able to profile cafestol and kahweol levels in in vitro tissues and also in flowers and zygotic embryos of Coffea species. The diterpene profiling in in vitro tissues would be of relevance in future to obtain somaclonal variants with their reduced levels.