Generation of dipeptidyl peptidase IV (DPP-IV) inhibitory peptides during the enzymatic hydrolysis of tropical banded cricket (Gryllodes sigillatus) proteins
posted on 2018-02-21, 10:06authored byAlice B. Nongonierma, Candice Lamoureux, Richard J. Fitzgerald
Tropical banded crickets (Gryllodes sigillatus) were studied for their ability to yield hydrolysates with dipeptidyl peptidase IV (DPP-IV) inhibitory properties. A cricket protein isolate (CPI) was prepared following extraction of the water soluble proteins from G. sigillatus powder (CP). The extraction yield and purity were 20.90 +/- 0.35% and 57.0 +/- 2.23%, respectively. Endogenous proteinase activities were detected in the CP, which were linked to the significant protein breakdown seen in this sample. Fifteen CPI hydrolysates (H1-H15) were generated with Protamex(TM) using a design of experiments (DOE) approach combining three parameters, temperature (40, 50 and 60 degrees C), enzyme to substrate ratio (E : S, 0.50, 1.25 and 2.00% (w/w)) and hydrolysis time (60, 150 and 240 min). The DPP-IV half maximal inhibitory concentrations (IC50) of the CPI hydrolysates ranged from 0.40 +/- 0.03/0.40 +/- 0.02 (H2/H3) to 1.01 +/- 0.07 mg mL(-1) (H7). Following simulated gastrointestinal digestion (SGID), the DPP-IV IC50 of CPI decreased (> 3.57 vs. 0.78 +/- 0.04 mg mL(-1)) while that of H5 increased (0.47 +/- 0.03 vs. 0.71 +/- 0.06 mg mL(-1)). This study has demonstrated for the first time that G. sigillatus protein hydrolysates are able to inhibit DPP-IV. The study of these hydrolysates in vivo is needed to evaluate their potential role in glycaemic management.
History
Publication
Food and Function;9, pp. 407-416
Publisher
Royal Society of Chemistry
Note
peer-reviewed
The full text of this article will not be available in ULIR until the embargo expires on the 27/11/2018