Enhancement in the production of phenolic compounds from Fagonia indica callus cultures via Fusarium oxysporum triggered elicitation

Fagonia indica Burm.f. (1768) is a medicinally important plant showing diverse pharmaceutical benefits. It is renowned for its ability to biosynthesize several anticancer and anti-inflammatory metabolites. For the eco-friendly and sustainable synthesis of phytochemicals and plant biomass, a biotechnological technique, “elicitation,” is a highly effective method in various in vitro cultures. The present study includes using various concentrations of Fusarium oxysporum Schlecht. as an elicitor in callus cultures of Fagonia indica. The main goal was to achieve enhancement in biomass production and secondary metabolism. The findings demonstrated that maximum biomass production (FW: 167.42 ± 3.99 g per 100 mL; DW: 12.53 ± 1.04 g per 100 mL) was observed at 50 mg L⁻¹ of Fusarium oxysporum as compared to the control. Secondary metabolites showed immense production (phenolic content (9.68 ± 0.23 µg mg⁻¹); flavonoid content (2.814808 ± 0.11 µg mg⁻¹)) in callus cultures treated with 10 mg L⁻¹ of Fusarium oxysporum as compared with control. Moreover, the cultures possessed the highest antioxidant capacity, as determined by 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS^•+) radical cation based assay and α, α-diphenyl-β-picrylhydrazyl (DPPH) free radical scavenging assay, ((821.51 ± 3.20 µmol TEAC per mg DW of ABTS inhibition) (91% ± 1.45 of DPPH inhibition)) at 10 mg L⁻¹ concentration of Fusarium oxysporum, and the maximum ferric ion reducing activity (219.29 ± 2.36 µmol TEAC per mg DW) was noticed at 1.0 mg L⁻¹ concentration of F. oxysporum. Fagonia indica cultures also indicated the highest percent inhibition against cyclooxygenases (COX-1: 51.93% ± 1.74 and COX-2: 40.57% ± 1.99), lipoxygenase (15-LOX: 65.72% ± 1.44), and phospholipase A2 (sPLA2: 49.29% ± 1.75), when treated with different concentrations of F. oxysporum. HPLC analyses showed a significant accumulation of pharmacologically active components in the treated samples, with kaempferol (1245.56 mg g⁻¹) and myricetin (1139.63 mg g⁻¹) as the most accumulated compounds in the cultures with 10.0 mg L⁻¹ concentration of Fusarium in contrast to the control. These findings revealed that in callus cultures of F. indica, F. oxysporum could boost biomass accumulation and secondary metabolite production.