Streptomyces spp. in Arid and Savannah Ecosystems: Effects on the Inhibition of Actinomycetoma Pathogens

Background Knowledge of the ecological and soil differences between arid and savannah ecosystems is essential for assessing their biodiversity and potential for agricultural and disease-controlling applications. Arid zones are characterized by extreme temperatures and limited rainfall, supporting unique soil types that influence microbial communities. This study examined soil Streptomyces spp., known for their antibiotic properties, focusing on their inhibitory effects against Streptomyces sudanensis, a pathogen associated with actinomycetoma. Methodology Soil samples (n = 7) were collected, and physicochemical parameters, along with enzyme activities, were analyzed. Streptomyces spp. were isolated, characterized morphologically and phenotypically, and identified molecularly via 16S rRNA gene sequencing. Their inhibitory effects against S. sudanensis were evaluated using agar-based bioassays. Results Streptomyces spp. (n = 64), including Streptomyces griseostramineus, were identified. The results indicated significant ecological differences: arid sites had high temperatures (29.7°C) and low rainfall (70 mm) with nutrient-poor Yermosols, whereas savannah sites had higher rainfall (501 mm) and nutrient-rich Arenosols and Vertisols. Inhibition zones varied significantly, with arid ecosystem isolates showing a higher mean inhibition value (2.8411) compared to savannah isolates (1.7139). Statistical analysis verified a significant difference in mean inhibition (t = 2.589, p = 0.0126), suggesting distinct inhibitory capacities linked to the ecosystem. Conclusions This study emphasizes the significant ecological and soil differences between the ecosystems and proves that soil Streptomyces spp. in arid regions possess distinctly higher inhibition potential against S. sudanensis, suggesting their potential as biological agents in these environments.