Ultrasound‑assisted extraction, multi‑omics, and bioactivities of phenolic acids from Amomum tsao-ko: a functional food perspective

Amomum tsao-ko fruits, consumed as a spice and traditional Chinese medicinal ingredient in Southwest China, are rich in phenolic acids with potential health benefits, yet systematic studies on their extraction, diversity, and functions are limited. We optimized ultrasound‑assisted extraction (UAE) using single‑factor experiments and Box‑Behnken design. The optimal UAE conditions (69% ethanol, 1:20 material‑liquid ratio, 22 min, 0.075 mm particle size) yielded 12.33 mg/g. Screening of 27 accessions revealed wide variation in total phenolic content (3.69–19.59 mg/g) and strong correlations with DPPH and FRAP antioxidant capacities. UPLC‑MS/MS metabolomics identified 285 phenolic acid metabolites in fresh and dried fruits of three accessions. Principal component analysis showed drying as the dominant factor shaping the metabolome. Transcriptomics linked high DCS and CURS1_2 expression to elevated accumulation of bioactive curcuminoids (bisdemethoxycurcumin, dihydrocurcumin, hexahydrocurcumin). Network pharmacology and molecular docking predicted these curcuminoids may interact with metabolic and inflammatory targets. Functional assays demonstrated that extracts rich in these compounds exhibited potent α‑glucosidase inhibitory and antibacterial activities against Staphylococcus aureus and Bacillus subtilis . Collectively, this study provides a comprehensive workflow from extraction optimization to functional evaluation of phenolic acids from A. tsao-ko , supporting its potential as a source of functional food ingredients.