The mycobiont and whole thallus cultures of Bel. were established using soredia as an inoculum.The mycobiont Roccella montagnei cultures showed optimum growth, biomass and biosynthesis of compounds in Lilly and Barnett medium with glucose as a carbon source, micronutrients and vitamins. After the incubation period of 180 days, the cultures were harvested, and their biomass and secondary compound profiles were analysed. The HPTLC chromatogram of the acetone extract of erythrin the NT and mycobiont cultures revealed as the major biosynthesized compound in both and identified as a key biosynthate by Further, the NT biosynthesized 5 R. montagnei. additional compounds and the mycobiont cultures biosynthesized 6 additional compounds. The molecular identity of the cultured mycobiont was confirmed using nuclear ribosomal Internal Transcribed Spacer (ITS) as well as the secondary chemistry. Lichen compound erythrin was identified as a key biosynthate by the cultures.