Inhibitory activity of insect curcumin protein particles on α-glucosidase and their synergism with acarbose under simulated digestion

• IB-KC and IB-KO had the highest total curcumin, over 20 mg/g. • ID-KC and ID-KO showed the highest total phenolic content. • CPPs had >40% solubility and protein content up to 38.34%. • ID-KC-UD strongly inhibited maltase and sucrase enzymes. The aim of this study was to develop alternative insect proteins with good nutritional value and bioactivity to create added value. Turmeric Curcuma longa L. (KC) and Curcuma zedoaria Rosc. (KO) were used, and adsorption with two insect proteins black gold crickets protein (IB) and house crickets protein (ID) was studied. These were compared with soy protein (SP) to produce curcumin protein particles (CPP): IB-KC, ID-KC, SP-KC, IB-KO, ID-KO, and SP-KO. Adsorption efficiency and physicochemical properties were investigated. Bioaccessibility after in vitro simulated digestion, α- glucosidase inhibitor activity in rat intestines (maltase and sucrase), and interaction with acarbose were examined. IB-KC and IB-KO had the highest total curcumin (TC) values at 20.99±0.51 and 20.11±0.70 mg g⁻¹, respectively, while ID-KC and ID-KO showed the highest total phenolic (TP) values at 1.584±0.01 and 1.136±0.02 mg g⁻¹. CPP showed water activity between 0.24–0.37, protein content 22.14%–38.34%, fat 1.25%–3.75%, pH 6.21–6.87, and solubility over 40%. After digestion, TC values changed less significantly than TP (p<0.05). CPP exhibited α -glucosidase inhibitory activity. ID-KC-UD showed the strongest activity for maltase and sucrase with IC₅₀ values of 2.57±0.11 and 2.50±0.13 mg mL⁻¹, respectively. IB-KC and IB-KO in the intestinal phase showed synergistic activity with acarbose. Thus, CPP from this study offers insect protein enriched with turmeric extract, combining nutritional and antidiabetic benefits.