Assessment of secondary metabolites and bioefficacies of Peltophorum pterocarpum (DC.) Baker ex K. Heyne cell cultures

Peltophorum pterocarpum (DC.) Baker ex. K. Heyne, is reputed for its medicinal importance. Its bark is used for dysentery, tooth powder, eye lotion, embrocating for pains and sores and bark also gives a dye of yellow color. In the present study, cell cultures of leaf explants were established on MS medium supplemented with benzene-6-aminopurine (BAP; 2 mg/L) and naphthalene acetic acid (NAA; 0.5 mg/L). Callus was harvested at the transfer age of 2, 4, 6, 8 and 10 weeks, dried, extracted in ethanol. Total levels of phenolics and flavonoids as also antimicrobial (agar well diffusion method) and antioxidant (DPPH and FRAP method) efficacies were evaluated. On phytochemical investigation, β-sitosterol and bergenin were isolated and identified. Higher levels of total phenolics and flavonoids were recorded in 8 weeks-old callus extract (12.40 ± 1.44 mg GAE/gdw and 22.5 ± 0.08 mg QE/gdw). In DPPH method 4, 6 and 8 weeks-old calli exhibited similar activity with IC₅₀ value of 0.06 mg/mL. Likewise, 8 weeks-old callus exhibited higher FRAP activity (98.33 ± 10.40 mg AAE/g dw). On antibacterial screening, 10 weeks-old callus demonstrated appreciable results with inhibition zones of 24.33 ± 0.57, 21.00 ± 1.00, 11.00 ± 1.00 and 10.00 ± 0.00 mm against K. pneumoniae, B. subtilis, S. aureus and E. coli respectively.