Antimicrobial Profile from Frog Skin Peptides

Abstract

This study evaluates the antimicrobial efficacy of frog skin-derived peptides Magainin 1, Magainin 2, and Bombesin againstBacillus subtilis, Escherichia coli,andTrichoderma harzianum. Experimental setups involved uniform inoculation of the microorganisms on 20 mL agar plates, treated with varying volumes (1.5 µL, 5 µL, and 10 µL) of each peptide (10 mg/mL). ForBacillus subtilis, Magainin 2, and Bombesin demonstrated significant antibacterial activity, with inhibition zones increasing in size proportionally to the peptide volumes. Magainin 2 showed the highest efficacy, surpassing ampicillin at higher volumes. InEscherichia coli, similar dose-dependent antibacterial effects were observed, with Magainin 2 again showing superior performance, matching or exceeding the inhibition zones of ampicillin. Notably, Magainin 2, and Bombesin exhibited antifungal activity againstTrichoderma harzianumwith Amphotericin resistance. These antibacterial peptides show inhibitory activity on fungi, gram-positive higher than gram-negative bacteria. These findings highlight the potential of Magainin 2, and Bombesin as antimicrobial agents except of Magainin 1.