Elicitation strategies for the production of bioactive triterpenoid saponins in cell suspension cultures of Gnidia glauca (Fresen.) Gilg

Gnidia glauca (Fresen.) Gilg leaf callus cell suspension culture was initiated in Murashige and Skoog liquid medium supplemented with 0.2 mg L −1 isopentenyl adenine and mg L −1 2,4-dichlorophenoxyacetic acid, elicitors and elicitor-precursor combinations viz. salicylic acid, methyl jasmonate, methyl jasmonate-fructose, and ketoconazole-glucose. Suspension-cultured cells treated with different concentrations of elicitors (50, 100, and 200 μM) for the increased accretion of triterpenoid saponins and evaluated for growth biomass and total saponin content (6, 12, 18, and 24 days). The highest accumulation of triterpenoid saponin with methyl jasmonate (58 ± 3.55 mg g −1 DCW), methyl jasmonate-fructose (78 ± 5.77 mg g −1 DCW), and ketoconazole-glucose synergistic combination (87.9 ± 3.40 mg g −1 DCW) was obtained over the course of 18 days at a concentration of 100 μM which were 4.8, 6.24, and 7.77 folds higher than the respective non-elicited control, but 5.5 folds higher amount of saponin was obtained in salicylic acid treatment (69.88 ± 5.7 mg g −1 DCW at 200 μM). A negative correlation has been observed between the accumulation of biomass and saponin production. The results of Thin layer chromatography, Reverse phase-High performance liquid chromatography, Fourier-transform Infrared spectroscopy, and High resolution-liquid chromatography mass spectroscopy revealed the presence of triterpenoid saponins. The cytotoxic effect of ketoconazole-glucose treated cell suspension extract on human cancer cell lines (A-549, A-375, and MCF-7) was evaluated using Cisplatin as a positive control. The results showed that the cell suspension cultures elicited with ketoconazole-glucose (100 μM) could be useful strategy for the large scale production of biologically active triterpenoid saponins. • Gnidia glauca 's therapeutic properties are attributed to triterpenoid saponins. • Cell suspension elicitation enhances triterpenoid saponins. • Elicitation employed elicitors and precursor molecules. • Cytotoxic effect of KCZ-G treated extracts assessed on A-549, A-375, and MCF-7.