Supervised by Nahrowi and Anuraga Jayanegara
Hermetia illucens larvae (HiL) is a protein source alternative and can act as functional feed in the poultry industry. This study aimed to optimize the HiL alkali extraction and evaluated the amino acid quality and antibacterial activity. Response surface modelling (RSM) was used to optimize the HiL extraction process and yield assessment. RSM following by three variables and three levels based on Box-Behnken design. The extraction method used alkali extraction procedure with variable X 1 = NaOH concentration, X 2 = HCl concentration, and X 3 = precipitation volume. Inhibitory zone assay used Staphylococcus aureus, Bacillus subtilis, Salmonella typhimurium and Escherichia coli. Validation of the model has a lack of fit value (P>0.05), indicate the model is valid. The essential amino acid index (EAAI) dried and extract HiL is 95.96% and 99.57%, respectively. Dried HiL and extract has biological values (BV), respectively, 92.90% and 96.83%. Dried HiL and extract did not have the antibacterial activity to inhibit gram-positive and gram-negative bacteria, besides that zinc-bacitracin has inhibitory zone 23.00, 19.50, 14.00 and 19.07 mm to inhibit Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6051, Salmonella typhimurium ATCC 13311 and Escherichia coli ATCC 8639, respectively. It can be concluded, the optimum points of the extraction process are NaOH 2.35 M, HCl 2.76 M, and precipitation volume 25.28 ml with yield 23.03%. The EAAI and BV of HiL extracts higher than dried HiL. HiL extracts did not present antibacterial activity.