Adaptation strategies in haloalkaliphilic fungi: Aspergillus salinarum, cladosporium sphaerospermum, and penicillium camemberti.

BACKGROUND

Extremophilic fungi thrive in extreme environments, revealing life's origins and enhancing biodiversity while offering insights into evolutionary biology. This study investigates the adaptation mechanisms of haloalkaliphilic fungi Aspergillus salinarum, Cladosporium sphaerospermum, and Penicillium camemberti, isolated from Egyptian soils, adapted to life under extreme conditions of high salt (15%) and alkaline pH (10). These properties make them interesting for fundamental research and the exploration of biotechnological potential.

RESULTS

These fungi exhibited increased levels of soluble proteins and lipids in cell-free extracts under stress conditions. Enzyme activities, specifically peroxidase and tyrosinase, were significantly induced, with maximum induction varying by species and incubation time. Significant amounts of organic acids, including citric, oxalic, and butyric acids, were detected in higher quantities under extreme conditions, with total organic acid content increasing by up to 2.97%. The culture filtrates demonstrated enhanced antimicrobial activity against various Gram-positive and Gram-negative bacteria, Bacillus Subtilis (ATCC 6633); Staphylococcus aureus (ATCC 6538); Escherichia coli (ATCC 8739); Pseudomonas aeruginosa (ATCC 90274); yeast, Candida albicans, but not against Aspergillus niger.

CONCLUSIONS

These findings highlight the potential industrial applications of these fungi in biotechnology and pharmaceuticals due to their biochemical responses and antimicrobial properties.