Polyphenol-rich extract from Cyamopsis tetragonoloba straw: Characterization, bioactivity, cytotoxicity, and anti-obesity potential

India annually generates over 683 million tonnes of agricultural waste, with Cyamopsis tetragonoloba straw representing an unexplored lignocellulosic byproduct possessing significant biotechnological potential. This study aims to evaluate the phytochemical, functional, and bioactive properties of Cyamopsis tetragonoloba straw, whereas phytochemical profiling showed the presence of polyphenolic compounds such as cinnamic acid, chlorogenic acid, caffeic acid, and vanillic acid. Proximate composition of straw was moisture (4.43 %), fat (0.30 %), protein (4.89 %), ash (2.16 %), and fiber (39.65 %) content. Moreover, the straw exhibits techno-functional properties, including a density of 0.34 g/cm³ , a tapped density of 0.58 g/cm³ , a water-holding capacity of 5.08 g/g, and an oil absorption capacity of 4.85 g/g. Antioxidant potential was confirmed through DPPH radical scavenging activity (3.83 mg QE/g), total phenolic content (4.15 mg GAE/g), and total flavonoid content (3.83 mg QE/g). Furthermore, Fourier-transform infrared (FTIR) spectroscopy identified characteristic functional groups linked to bioactive constituents. Antimicrobial assays demonstrated a concentration-dependent inhibitory effect, with significant ( p < 0.05) activity observed at different concentrations of 50 and 100 µL/mL. Additionally, cytotoxicity analysis shows the highest inhibitory effects at a concentration of 50 µL/mL of straw extract. It also showed significantly ( p < 0.05) higher amylase (90.99 %) and lipase inhibition activity (71.86 %). Overall, it exhibits promising potential as a sustainable source of bioactive compounds with potential applications in the nutraceutical, pharmaceutical, and biodegradable packaging industries. Further research is needed to optimize extraction methods and evaluate the large-scale industrial feasibility. • Bioactive compounds in underutilised Cyamopsis tetragonoloba straw. • Functional properties for food and nutraceutical applications. • Anti-obesity efficacy through in-vitro experimental studies. • Promoted straw valorization for sustainable health and waste management solutions.