ELICITATION OF FORSKOLIN IN CULTURES OF RHIZACTONIA BATATICOLA-A PHYTOCHEMICAL SYNTHESIZING ENDOPHYTIC FUNGI

Abstract

Objective: Coleus forskohlii is the only known source of forskolin-a labdanediterpene and a highly valuable phytochemical. Coleus forskohlii has been listed as endangered plant; therefore, efforts have been made to find novel sources of forskolin production. Methods: Endophytic fungi were isolated from Coleus forskohlii tissue and screened for forskolin production by using thin layer chromatography (TLC) method. Further, 16 different elicitation media combinations were used to enhance the forskolin content. Results: In this study, out of 38 strains of endophytic fungi from Coleus forskohlii only 2 strains EF1 and EF2 were found to synthesize forskolin in mycelium, whereas EF2 was found to release the forskolin into the broth. Further, EF2 was identified as Rhizactonia bataticola accession no. NFCCI 2028. Further, T 2 S 1 media showed dramatic effects on enhanced forskolin production in mycelium. However, there was a significant increase about four folds in broth which corresponded to 0.5 mg compared to T 1 S 1 media where it was 0.09 mg. Conclusion: The present study suggests that the forskolin producing Rhizactonia bataticola and T 2 S 1 media can serve as potential materials for large scale enhancement of forskolin production.