Effect of subcritical water extraction conditions on the activity of alcohol metabolizing enzymes, ACE inhibition, and tyrosinase inhibition in Protaetia brevitarsis larvae

In order to develop processing methods with high physiological activity for Protaetia brevitarsis larvae (PBL), subcritical water (SCW) extraction was applied. The dried powder (1 g) of PBL was extracted with 10 mL distilled water at 100, 200, and 300 degrees C for 30 min. The SCW treatment significantly (p < 0.05) increased some physiological activities of the PBL extracts. The SCW extract at 300 degrees C increased alcohol dehydrogenase, acetaldehyde dehydrogenase, and tyrosinase inhibitory activities from 192.3 +/- 4.1% to 452.2 +/- 0.5%, 125.4 +/- 2.9% to 153.3 +/- 0.4%, and - 7.0 +/- 0.7% to 26.1 +/- 1.4%, respectively, compared to the extract at 100 degrees C. Contrarily, the inhibition activity of angiotensin converting enzyme was the highest at 200 degrees C. These results suggest that SCW is a suitable method to extract and maintain the physiological activity of PBL.