Elicitation of silver nanoparticles enhanced the secondary metabolites and pharmacological activities in cell suspension cultures of bitter gourd

This study describes the influence of bio-synthesized silver nanoparticles (AgNPs) on phytochemicals and their pharmacological activities in the cell suspension cultures (CSC) of bitter gourd. To standardize the effect of sucrose, plant growth regulators, medium, AgNPs and growth kinetics for the biomass and bioactive compounds accumulation in CSC of bitter gourd. The medium comprising MS salts, sucrose (30 g/L) with 2,4-D (1.0 mg/L) and TDZ (0.1 mg/L) at 28 days of CSC was appropriate for biomass and bioactive compound accumulation. The contents of silver, malondialdehyde and hydrogen peroxide were highly elevated in AgNPs (10 mg/L)-elicited CSC when compared with non-elicited CSC. AgNPs (5 mg/L) elicited CSC extracts had significantly enhanced the production of total phenolic (3.5 +/- 0.2 mg/g), and flavonoid (2.5 +/- 0.06 mg/g) contents than in the control CSC extracts (2.5 + 0.1 and 1.6 + 0.05 mg/g). AgNPs (5 mg/L) elicited CSC showed a higher amount of flavonols (1822.37 mu g/g), hydroxybenzoic (1713.40 mu g/g) and hydroxycinnamic (1080.10 mu g/g) acids than the control CSC (1199, 1394.42 and 944.52 mu g/g, respectively). Because of these metabolic changes, the pharmacological activities (antioxidant, antidiabetic, antibacterial, antifungal and anticancer) were high in the AgNPs (5 mg/L)-elicited CSC extracts in bitter gourd. The study suggested the effectiveness of elicitation process in enhancing the accumulation of phenolic compounds and pharmacological activities. AgNPs-elicited CSC offered an effective and favorable in vitro method to improve the production of bioactive compounds for potential uses in pharmaceutical industries.