Optimization of Antimicrobial Peptide (AMP) Extraction from Justicia gendarussa Leaves Using Box-Behnken Design

This study aimed to determine the optimal conditions for extracting antimicrobial peptides (AMPs) from Justicia gendarussa Burm. F. leaves and to identify AMPs that have potential antibacterial activity. Extraction optimization was performed using a Box-Behnken design, and total protein levels were measured using the Bradford method. SDS-PAGE was used to identify AMPs, and the well diffusion method was used to test their antibacterial activity. The results showed that the optimum extraction conditions were an acetic acid concentration of 14.9%, an extraction time of 2.9 h, and a sample-to-solvent ratio of 1:3. The AMP from J. gendarussa leaves was predicted to have a molecular weight of ~11 kDa. The crude extracts exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus, with inhibition zones of 8.61 mm and 22.85 mm, respectively. These findings suggest that AMP derived from J. gendarussa leaves possesses promising antibacterial properties, thus demonstrating its potential as a viable source for developing antibacterial agents in the context of the antibiotic industry.