Enhancing the aervine and methylaervine production in in vitro cultures of Aerva javanica (Burm. F.) Schult via elicitors and Agrobacterium rhizogenes-mediated hairy root cultures

An understanding of plant secondary metabolites may prove to be important for novel drug development. The objective of this investigation was to enhance the biosynthesis of alkaloid compounds aervine and methylaervine in callus-derived cell suspension cultures of Aerva javanica using biotic and abiotic elicitors. The effect of five different elicitors on the biosynthesis of aervine (AE) and methylaervine (MAE) contents was studied for 20 days to determine the concentrations suitable for their accumulation in A. javanica. The callus obtained from the shoots of A. javanica on Murashige and Skoog (MS) medium containing 2.0 mg L⁻¹ 2,4-dichlorophenoxy acetic acid (2,4-D) and 0.5 mg L⁻¹ α-naphthalene acetic acid (NAA), and their cell suspension cultures were used for the elicitation purposes. The result proved the maximum accumulation of AE and MAE contents in cell suspension culture. It was found to be 72.26 ± 0.30 mg g⁻¹ DW of MAE, showing an increase of 8.66-fold, and AE content (7.48 ± 0.39 mg g⁻¹ DW) in sodium carbonate (Na₂CO₃), whereas AE (34.10 ± 0.84 mg g⁻¹ DW) and MAE (9.69 ± 0.04 mg g⁻¹ DW) showed a 2.51-fold increase in salicylic acid. It was observed that the production of hairy root using Agrobacterium rhizogenes (MTCC 532) helps in improving aervine (42.22 ± 1.04 mg g⁻¹ DW) and methylaervine (8.30 ± 0.09 mg g⁻¹ DW) accumulation. This study will serve as an alternate protocol to improve alkaloid quantity as well as quality by elicitor stimulation. Furthermore, it may help in the sustainable production of A. javanica taxon and thereby helping in rescuing the natural sources recommended to cure several ailments.