Genetic and phytochemical analysis of the in vitro regenerated Pilosocereus robinii by ISSR, SDS–PAGE and HPLC

•The first study to be oriented towards micropropagation alongside with in vitro regeneration of the endangered key tree-cactus Pilosocereus robinii.•The plants were successfully acclimatized in the greenhouse as a complementary step for insurance of real cultivation of this endangered plant.•Somaclonal variation between in vitro micropropagated plants were analyzed using PCR-ISSR markers and SDS–PAGE protein to ensure the in vitro grown plant fidelity to the mother plants.•The phytochemical analysis of Pilosocereus robinii was meant to expand its nutraceutical and pharmaceutical utilization.

Pilosocereus robinii is a rare species which is experiencing sudden population collapse. Identifying and developing effective conservation and management strategies to halt the forestall extinction of this species is crucial. The present study was conducted to assess the best conditions for in vitro propagation of this plant in regard to its morphogenic, genetic as well as the chemical potentials. A successful in vitro propagation system of P. robinii has been developed. MS hormone-free medium induced the best root morphogenic potential. The plants were acclimatized in the greenhouse at 100% survival rate. Besides, the somaclonal variations between the in vitro raised plants were analyzed using PCR-ISSR markers and SDS–PAGE protein, where the regenerated explants on MS medium supplemented with TDZ were the highest in inducing new specific marker bands. Sh6 ISSR primer showed the highest polymorphism value, 81.8% with 33 total amplified fragments, while Sh3 ISSR primer showed the lowest value with polymorphic percentage of 14.3%. Furthermore, SDS–PAGE protein analysis showed no variation in protein pattern of the studied treatments. On the other side, HPLC analysis of the in vitro plantlets extracts has shown that 2iP based treatments were the highest in organic acids accumulation, while the phenolic constituents' accumulation was found to reach its peak in the BA based treatments.