Characterization and bioactivity of β- ecdysterone from cell cultures of Trianthema decandra L.

Abstract

In the present study, cell cultures from the nodal explants of Trianthema decandra L. were established on Murashige and Skoog’s (MS) medium supplemented with different concentrations (0.5, 1, 1.5, and 2 mg/L) of indole 3-acetic acid (IAA), 2,4-dichlorophenoxyacetic acid (2,4-D) and kinetin (Kn). Induction of callus was promising in MS medium supplemented with 1.5 mg/L 2,4-D after 25 days of inoculation. Their total phenolics and flavonoids levels were estimated and compared with those of in vivo. Antimicrobial (agar well diffusion method) and antioxidant (DPPH and FRAP methods) activities were studied. Further, six-weeks-old callus grown on MS medium with 2,4-D (1.5 mg/L) were harvested, dried and extracted using absolute methanol. Methanolic extracts of callus showed maximum inhibition against B. subtilis, P. aeruginosa, and A. flavus (IZ 14.33±0.32 mm, 15.66±0.32 mm and 13.33±0.65 mm, respectively) as compared to in vivo plant extract. Similarly, in the case of DPPH activity, methanolic extract of the callus demonstrated more antioxidant potential than in vivo. At 0.8 mg/mL concentration of callus extract showed inhibition of 85.02% as compared to 83.38% of plants grown in vivo. Likewise, in the case of the FRAP method, there is no significant difference in antioxidant potential (303±3.37 ascorbic acid equivalent/ mg in callus; AAE/mg) as compared to in vivo plant (310±10.01 AAE/mg). A new compound β- ecdysterone (20-hydroxyecdysone), was isolated and identified from the callus of this plant, which was also tested for its antimicrobial and antioxidant activity. Isolated pure compound β- ecdysterone were tested against selected strains of bacteria and fungi and prove effective E. aerogenes and K. pneumoniae with Minimum inhibitory concentration of 250 µg/mL concentration (IZ 11.00±0.00 mm and 12.00±0.00). compound does not impressive for antifungal profile.