Revealing culturable fungal microbiome communities from the Arabian Peninsula desert representing a unique source of biochemicals for drug discovery and biotechnology

Abstract

Background: Microbes living at extremes evolve unique survival strategies to adapt to challenging environmental conditions. Among these strategies is their distinctive metabolic potential and ability to produce specialized metabolites enabling them to compete for limited resources and defend against predators. These metabolites have significant potential in pharmaceutical and industrial applications, particularly in the development of drugs and biochemicals.

Objectives: This study aimed to investigate the culturable fungal communities associated with four desert plants and their surrounding soils in the Arabian Peninsula desert to identify their bioactive properties.

Methods: A total of 12 distinct fungal species were isolated from the plants and soils. Each plant hosted a unique set of fungi, demonstrating the diversity of desert-adapted fungal communities. Biological activities of the fungal extracts were evaluated through various assays, including antimicrobial, antifungal, anticancer, and antioxidant properties.

Results: Panicum turgidum harbors the most diverse fungal community, dominated by genera such as Mucor, Aspergillus, Colletotrichum, Alternaria, and Chaetomium. Aspergillus species comprise 33% of the total isolates, followed by Fusarium at 16%. All extracts exhibit diverse activities, with Aspergillus species demonstrating the highest antioxidant activities and total phenolic and flavonoid content. Fungi from P. turgidum, particularly Mucor sp., Aspergillus sp., and Curvularia sp., display potent activity against Staphylococcus aureus, while Mucor sp., Chaetomium sp., and Curvularia sp. exhibit moderate inhibition against Pseudomonas aeruginosa.

Conclusion: This study highlights the importance of exploring extremophilic microorganisms, such as those found in desert ecosystems, as they offer a wealth of compounds that could address current challenges in drug discovery and biotechnology.

Keywords: Desert microbiome; and cytotoxic.; antimicrobial; antioxidant; bioactive molecules; culturable fungi.

Figure 1.. Isolation of culturable fungal species from desert plants.

The figure illustrates the process of isolating fungi from plant material and subsequent subculturing to obtain pure isolates.

Figure 2.. Activities of the crude extracts of cultured fungal species.

The graph demonstrates three activities including antioxidant activities measured as % of DPPH reduction, total phenolic content measured as μg of EAG per mg of the extract and total flavonoid contents measured as μg of EQ per mg of the extract. Data are the average of three replicates.

Figure 3.. Antimicrobial activities of crude extracts from cultured fungal species, measured as MIC.

The graph presents results from two experiments: A) antibacterial activities against Gram-positive indicator S. aureus and Gram-negative indicator P. aeruginosa, and B) antifungal activities against the human-associated yeast C. albicans and the plant pathogenic fungus F. graminearum. Data represent the average of three replicates, with bars indicating the standard deviation of the mean.

Figure 4.. Cytotoxic activities of the fungal extracts against two cancer cell lines (A549 and H292).