Boosting Antioxidant Potential in Amaranth Sprouts: Assessing Salicylic Acid and Hydrogen Peroxide Treatments

• SA and H₂O₂ boost amaranth sprout antioxidants by up to 369%. • Germination time and elicitors significantly increase phenolic content. • Optimal SA (5.5 ppm) enhances flavonoids; H₂O₂ excels at 340 ppm. • Elicitors alter betalain profiles and improve sprout color (ΔE > 5.0). • Elicitation is Non-GMO biofortification strategy for functional food development. Amaranth is a nutrient-rich pseudocereal valued for its high protein content and bioactive compounds with antioxidant properties. This study investigated the effects of salicylic acid (SA) and hydrogen peroxide (H₂O₂) elicitors, imbibition time (2–8 h), and germination duration (72–120 h) on the bioactive compounds in amaranth sprouts. A factorial design with varying elicitor concentrations (0–340 ppm H₂O₂, 0–11 ppm SA) was used. Bioactive compounds and antioxidant activity (ABTS, DPPH, FRAP) were quantified spectrophotometrically, and phenolic profiling was performed via FIA-ESI-FTICR-MS. Germination significantly increased phenolics and betalains. SA (5.5 ppm) and H₂O₂ (340 ppm) enhanced phenolics and flavonoids, while longer germination (120 h) maximized betalains. Antioxidant activity, determined by the ABTS assay, increased by up to 3.69-fold relative to raw amaranth (p < 0.05). Elicitation elevated quercetin, kaempferol, and betaxanthin levels. SA was particularly effective. These findings support the use of elicitation to enhance amaranth's functional properties for food and nutraceutical applications.