Impact of Sowing Dates and Nitrogen Levels on the Phenolic Profile, Antioxidant, and Enzyme Inhibitory Activities of Ricinus communis L. Roots

A wide range of biological effects, including antioxidant, antimicrobial, anti‐inflammatory, and antiproliferative activities, have been attributed to phenolic compounds, a group of bioactive molecules naturally occurring in plant tissues and increasingly valued for their industrial relevance. Notably, the present study demonstrates that sowing date is a key determinant of phenolic content and associated biological activities. Comprehensive LC–MS/MS analysis revealed that gallic acid (20.66 mg/g extract), ellagic acid (15.78 mg/g extract), and quinic acid (11.12 mg/g extract) were the predominant phenolic constituents of the ethanol extracts obtained from the roots of Ricinus communis L. In addition, the extracts exhibited moderate antioxidant activity in DPPH, ABTS, and CUPRAC assays, with IC 50 values of 37.94 ± 0.58 and 9.26 ± 0.08 μg/mL and an A 0.5 value of 30.91 ± 0.56 μg/mL, respectively. Enzyme inhibition assays revealed moderate inhibitory activity against urease inhibition%: 51.17 ± 0.77, and α ‐amylase inhibition%: 14.39 ± 0.17, whereas strong inhibition was observed against α ‐glucosidase inhibition%: 98.23 ± 1.03. These findings indicate that R. communis root extracts represent a promising source of bioactive compounds with notable α ‐glucosidase inhibitory potential and supportive antioxidant activity.