Investigations on the Chemical Composition and Antimicrobial Potency of Eucalyptus camadulensis (River Red Gum) Leaf Extracts

The search for new antimicrobials has been prompted by the serious global health concern of antimicrobial resistance. Strong anti-infective compounds are thought to be abundant in plants. Based on its ethnomedical use, examining the chemical components and antibacterial potency of Nigerian Eucalyptus camaldulensis was the aim of this investigation. The air-dried, powdered leaves of E. camaldulensis were extracted with methanol to get the crude extract. To test for phytochemicals, the extract was screened using standard protocols. The crude extract was separated into fractions that were soluble in hexane, chloroform, ethylacetate, and methanol-chloroform. The crude extract's and its fractions' activity was evaluated against Salmonella typhi, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Salmonella typhi, Aspergillus niger, and Candida albicans. The chemical components of the crude extract were identified by GC-MS analysis. Phytochemical analysis showed that phenols, carbohydrates, terpenoids, alkaloids, flavonoids, saponins, tannins, steroids/sterols, and volatile oils were present. The broadest range of antibacterial activity was shown by the crude extract. With a MIC value of 12.5 mg/ml, the hexane-soluble fraction, however, exhibited the highest activity against Salmonella typhi. A. niger and C. albicans were not inhibited by the crude extract or its fractions. The main compounds identified by the GC-MS analysis of the crude extract were long chain saturated and unsaturated carboxylic acids, esters, fatty acids, and fatty acid esters, with recognised biological activity. These findings demonstrate Eucalyptus camaldulensis's potential as a natural source of antibacterial compounds and validate its traditional use.