Silkworm Antimicrobial Peptides: Biochemical Insights and Applications

Bombyx mori, the domesticated silkworm, relies on a robust innate immune system to defend against microbial threats, and a central component of this defense is the production of antimicrobial peptides. These short, cationic molecules provide broad protection through multiple mechanisms including disrupting microbial membranes, disrupting microbial membranes, binding to surface structures, and inhibiting key intracellular processes such as protein synthesis or DNA replication. In addition to their antibacterial activity, silkworm antimicrobial peptides (AMPs) also help prevent the emergence of microbial drug resistance, making them promising candidates for sustainable antimicrobial strategies. Families such as cecropins, defensins, gloverins, moricins, attacins, and seroins exhibit distinct biochemical structures, amino acid compositions, and mechanisms of action that reflect both functional diversity and evolutionary adaptation. Their expression is tightly regulated through pathogen recognition and signaling pathways, with stage-specific and tissue-specific patterns that highlight their ecological relevance. Recent research emphasizes the promise of silkworm antimicrobial peptides in medicine, agriculture, and aquaculture, where they are being developed as alternatives to conventional antibiotics and pesticides. For example, they are explored as topical antibiotics in wound healing, as biopesticides for crop protection, and as immunostimulants to reduce antibiotic use in fish farming. Advances in genetic engineering, peptide design, and nanotechnology-based delivery systems are expanding their practical applications. At the same time, challenges related to stability, toxicity, production, and regulatory approval remain critical barriers to large-scale use. This review synthesizes current insights into the biochemical diversity, regulation, and applied potential of silkworm antimicrobial peptides, underscoring their value as natural models for next-generation antimicrobial strategies.