Salts, protease and their synergistic effect as catalysts in protein hydrolysis of black soldier fly larvae (Hermetia illucens)

Abstract

Hermetia illucens, also known as Black Soldier Fly Larvae (BSFL) meal, was used to evaluate the efficiency of salt, protease, and their combination as a catalyst in protein hydrolysis and protein denaturation. Three treatments on BSFL meal were conducted as 10% NaCl (Treatment 1), 10% TAPzyme (Treatment 2), and 10% NaCl and TAPzyme (Treatment 3). All treatments were supplied with 5 grams of BSFL meal. The samples were incubated according to their favourable conditions for hydrolysing and denaturing the BSFL's protein into smaller peptides. The Bradford assay method was applied to determine the percentage of protein concentration decreased, while SDS-PAGE illustrated the protein bands and peptides on gel electrophoresis. The percentage of protein concentration decreased in Treatment 3 was significantly (p < 0.05) higher than Treatment 1 and Treatment 2. In-gel electrophoresis, there were no protein bands, and peptides had appeared for Treatment 1 (sample X), but the high intensity of staining colour showed up at the bottom of the well. Compared with control (sample C), these results indicated that the BSFL's protein was partially hydrolysed as there were no protein bands and peptides that lie at the same molecular weight of protein in sample C. This finding suggested that the protease alone effectively enhances the protein hydrolysis based on protein characterisation by the SDS-PAGE method.