Anti-inflammatory and anti-hyperglycemia effects of mealworm (Tenebrio molitor larvae) protein extracted by four methods: alkali, salt, enzyme, and screw press.

ABSTRACT

The use of edible insect protein in food products is contingent on their biological effects. Conventional protein extraction methods are not only time-consuming and costly but also energy-intensive. There is a need for alternative techniques that maintain the bioactivities of insect proteins and are environmentally sustainable. This study compares the health functionality of mealworm (Tenebrio molitor larvae) concentrates obtained by conventional methods-alkali and salt (MS) extraction-and nonconventional methods-enzyme (ME) and screw press (MP)-to enhance their applicability despite lower protein concentration. Overall, MP exhibited the highest essential amino acids content, whereas ME showed the highest in vitro digestibility, total phenolic contents, and antioxidant capacities among all the concentrates. ME also had a significant cell proliferative capacity at concentrations ≥500 µg/mL. MS significantly inhibited tumor necrosis factor-alpha and interleukin-1beta secretion in lipopolysaccharide-treated Hep3B cells compared to other samples. As for anti-hyperglycemia effects, treatment with MS and ME for 2 and 5 min significantly increased the p-Akt/Akt ratio (MS, 1.34- and 1.61-fold; ME, 2.26- and 2.70-fold, respectively). In conclusion, enzyme treatment enhanced nutritional value and antioxidant capacity, whereas salt treatment potentially contributed to anti-inflammatory and anti-hyperglycemia activities. Hybrid extraction techniques combining conventional and nonconventional methods are suggested based on target applications, considering health benefits, environmental impact, costs, and efficiencies. PRACTICAL APPLICATION Four mealworm protein extraction methods (alkali/salt/enzyme/screw press) were compared for their nutritional and biological properties. Alkali extraction enhanced protein content, enzyme treatment improved nutritional value and antioxidant capacity, and salt-assisted extraction exhibited immunomodulatory effects in vitro. Notably, enzyme and salt treatments produced protein concentrates with significant antidiabetic and anti-hyperglycemic properties.