Environmental Aspergillus fumigatus Derived Antibiotics: Structure and Efficacy against Enteric Bacteria

Abstract

Antibiotic resistance poses significant clinical and public health challenges, leading to treatment failures, prolonged hospitalizations, and increased mortality. Enteric bacterial diseases are a major concern. The need for novel antibiotics from natural sources is pressing. This study explores the potential of antibiotics extracted from Aspergillus fumigatus mycelia against enteric bacterial pathogens. One hundred soil samples from hospital dumping sites were screened, yielding three Aspergillus fumigatus strains: DTO402 (AFO402), F7 (AFF7), and KMM4631 (AFK4631). The fungal isolates were grown in submerged culture, and their antibiotic production was evaluated. Structural elucidation using GC-MS revealed various bioactive compounds in each strain. AFK4631 produced oleic acid, hexacosanoic acid, erucic acid, and 10-methyl-E-11-tridece-1-ol-acetate, which showed significant (p ≤ 0.05) inhibitory activity against Salmonella enterica subspecies enterica serovar Typhi strains. Similar compounds were identified in AFD402 and AFF7, including oleic acid and hexacosanoic acid. The study demonstrates the potential of these Aspergillus fumigatus strains as sources of alternative antibiotics for treating enteric bacterial infections. The findings suggest that these natural compounds could provide a promising solution to the growing problem of antibiotic resistance. Further research is warranted to explore the therapeutic applications of these bioactive compounds.