Preparation of a crude extract of maggots
One hundred maggots were selected and 10 mL of TNE buffer (5 mmol/L EDTA, 10 mmol/L Tris- HCl, 150 mmol/L NaCl, pH 7.5) precooled at 4°C was added. After sufficient homogenization, the homogenate was centrifuged at 12000 r/min for 10 min at 4°C. The supernatant was transferred to a new tube, and three volumes of TNE buffer were added. The mixture was boiled for 2 min, cooled and centrifuged at 12000 r/min at 4 °C for 10 min. The resulting supernatant was a crude extract of maggots. The crude extract was filtered through a membrane with a pore size of 0.22 μm, and the ltrate was frozen at -80 °C. The freeze-dried powder was stored in a refrigerator at -20 °C for further use.