Evaluation of the Antimicrobial Activity of Selected Algal Extracts Against Pathogenic Bacteria and Candida Species In Vitro study

Background: The worldwide increase in microbial resistance to antibiotics necessitates immediate research on sustainable and advantageous natural treatment alternatives. Method: Algae isolated from the aquatic environment of Baqubah city (Khreesan River and Othmania River ) and subsequently identified using taxonomic references. The study utilized hexane and ethanol solvents to extract by maceration and shaking. After that, analyze the active compounds present in these algae species. After extraction, the compounds were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS) to fully characterize their chemistry and identify potential bioactive substances with therapeutic properties. To determine the antimicrobial properties of the ethanol and hexane extracts, in vitro experiments were conducted on three strains of Klebsiella, two strains of Pseudomonas, two strains of Acinetobacter, and , two strains of Candida albicans. They have also undergone testing for antibiotic resistance. Results: Cladophora glomerata and Mougeotia floridana are two species of algae isolated from the environment. The GC-MS analysis determined Several organic compounds, including phenolic compounds, nitrogen compounds, hydroxylamines, aldehydes, fatty acid methyl esters, diterpenoids, long-chain primary fatty alcohols, long-chain fatty acids, aromatic solvents, phenylpropanes, and alkanes. The findings revealed that the crude ethanolic extract of Cladophora glomerata exhibited the highest activity at a concentration of 100 mm/L, which was consistent with the performance of its crude hexane extract at the same concentration. Conversely, the crude ethanolic and hexane extracts of Mougeotia floridana demonstrated superior activity only at a higher concentration of 500 mm/L. When comparing the results of the algal extracts with the antibiotic susceptibility test according to the CLSI system, the algal extracts showed a remarkable superiority. This is attributed to the fact that the tested microorganisms exhibited a high level of resistance to conventional antibiotics. Conclusion: Since antibiotic resistance is on the rise worldwide, these algae have shown promise as potential alternative medicine projects.