Isolation of Three Secondary Metabolites from the Eucalyptus camaldulensis Dehnh. Plant for the First Time

Abstract

Objectives: Phytochemical screening and identification of certain types of secondary metabolites that not separated yet from the Eucalyptus camaldulensis plant. Background: E. camaldulensis Dehnh. (Family: Myrtaceae) is one of the most widely distributed species of eucalyptus trees and the original land of this variety is Australia. E. camaldulensis Dehnh. is the main species that distributed in various regions of Iraq. E. camaldulensis has active constituents rich in pharmacologically significant secondary metabolites with proven activities including anti-bacterial, anti-fungal, anti-viral, anti-oxidant, and others. Methodology: Defatting step of leaves and fruits separately with n-hexane was preceding the extraction process by maceration with 50% acetone followed by subsequent fractionation process and isolation step achieved by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Results: The resulting three fractions had been undergone preliminary chemical tests suggesting the presence of steroids, terpenoids, and tannins. The isolation process had been given rise to the separation of three phytoconstituents identified by different chromatographic techniques resulting in the confirmation of the non-polar compounds isolated from the hexane fraction comprising the phytosterol stigmasterol and the possible diterpene turraeanin J. The polar secondary metabolite isolated from the ethyl acetate fraction is the dimer tannin oenothein B. Conclusion: The Iraqi E. camaldulensis plant rich in various secondary metabolites presents diverse pharmacological activities. The first isolation might be around the world from the Eucalyptus genus, is the expected diterpene turraeanin J, and the first isolation from the species around the world are oenothein B and stigmasterol.