Microbial Natural Products: A Source of Novel Antibiotics and Immunomodulators

Natural products (NPs), especially those derived from microbes, have been important in serving as crucial sources of therapeutic agents because of their distinct bioactivities and structural variety. This chapter explores the historical, biological and pharmacological significance of microbial natural products, focusing on their roles in antimicrobial, anticancer, immunosuppressive, and anti-inflammatory therapies. Microorganisms such as bacteria and fungi produce secondary metabolites that demonstrate potent biological effects, including antibiotic, antiviral, antifungal, and immunomodulatory properties. With rising antimicrobial resistance, the need for novel treatments has led to emerging strategies like CRISPR-Cas gene editing, efflux pump inhibitors, and combination therapies. Commercial antibiotic development remains challenged by high costs and low profitability. Global collaboration and sustainable practices are essential to address the growing threat of antimicrobial resistance and to support future drug discovery from microbial sources.