Chemical Composition, Antibacterial Properties, and Anti-Enzymatic Effects of <i>Eucalyptus</i> Essential Oils Sourced from Tunisia
Sana Khedhri,
Flavio Polito,
Lucia Caputo,
Vincenzo De Feo,
Marwa Khamassi,
Oumayama Kochti,
Lamia Hamrouni,
Yassine Mabrouk,
Filomena Nazzaro,
Florinda Fratianni,
Ismail Amri
Affiliations
Sana Khedhri
Laboratory of Management and Valorization of Forest Resources, National Institute of Researches on Rural Engineering, Water and Forests, Ariana 2080, Tunisia
Flavio Polito
Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy
Lucia Caputo
Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy
Vincenzo De Feo
Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy
Marwa Khamassi
Laboratory of Management and Valorization of Forest Resources, National Institute of Researches on Rural Engineering, Water and Forests, Ariana 2080, Tunisia
Oumayama Kochti
Laboratory of Biotechnology and Nuclear Technology, National Center of Nuclear Science and Technology, Sidi Thabet, Ariana 2020, Tunisia
Lamia Hamrouni
Laboratory of Management and Valorization of Forest Resources, National Institute of Researches on Rural Engineering, Water and Forests, Ariana 2080, Tunisia
Yassine Mabrouk
Laboratory of Biotechnology and Nuclear Technology, National Center of Nuclear Science and Technology, Sidi Thabet, Ariana 2020, Tunisia
Filomena Nazzaro
Institute of Food Science, National Research Council, Via Roma, 60, 83100 Avellino, Italy
Florinda Fratianni
Institute of Food Science, National Research Council, Via Roma, 60, 83100 Avellino, Italy
Ismail Amri
Laboratory of Biotechnology and Nuclear Technology, National Center of Nuclear Science and Technology, Sidi Thabet, Ariana 2020, Tunisia
This study was conducted to examine the chemical composition of the essential oils (EOs) from six Tunisian Eucalyptus species and to evaluate their anti-enzymatic and antibiofilm activities. The EOs were obtained through hydro-distillation of dried leaves and subsequently analyzed using GC/MS. The main class of compounds was constituted by oxygenated monoterpenes, particularly prominent in E. brevifolia (75.7%), E. lehmannii (72.8%), and E. woollsiana (67%). Anti-enzymatic activities against cholinesterases, α-amylase, and α-glucosidase were evaluated using spectrophotometric methods. Notably, the E. brevifolia, E. extensa, E. leptophylla, E. patellaris, and E. woollsiana EOs displayed potent acetylcholinesterase (AChE) inhibition (IC50: 0.25–0.60 mg/mL), with E. lehmannii exhibiting lower activity (IC50: 1.2 mg/mL). E. leptophylla and E. brevifolia showed remarkable α-amylase inhibition (IC50: 0.88 mg/mL), while E. brevifolia and E. leptophylla significantly hindered α-glucosidase (IC50 Staphylococcus aureus and Listeria monocytogenes) and Gram-negative (Acinetobacter baumannii, Pseudomonas aeruginosa and Escherichia coli) bacterial strains. The E. extensa EO demonstrated the main antibiofilm effect against E. coli and L. monocytogenes with an inhibition > 80% at 10 mg/mL. These findings could represent a basis for possible further use of Eucalyptus EOs in the treatment of human microbial infections and/or as a coadjutant in preventing and treating Alzheimer’s disease and/or diabetes mellitus.
