title: Anti-plasmodial and insecticidal activities of the essential oils of aromatic plants growing in the Mediterranean area.
abstract: BACKGROUND
  Sardinia is a Mediterranean area endemic for malaria up to the last century. During a screening study to evaluate the anti-plasmodial activity of some aromatic plants traditionally used in Sardinia, Myrtus communis (myrtle, Myrtaceae), Satureja thymbra (savory, Lamiaceae), and Thymus herba-barona (caraway thyme, Lamiaceae) were collected in three vegetative periods: before, during and after flowering.
  
  
  METHODS
  The essential oils were obtained by steam distillation, fractionated by silica gel column chromatography and analysed by GC-FID-MS. Total oil and three main fractions were tested on D10 and W2 strains of Plasmodium falciparum in vitro. Larvicidal and adulticidal activities were tested on Anopheles gambiae susceptible strains.
  
  
  RESULTS
  The essential oil of savory, rich in thymol, was the most effective against P. falciparum with an inhibitory activity independent from the time of collection (IC50 17-26 μg/ml on D10 and 9-11 μg/ml on W2). Upon fractionation, fraction 1 was enriched in mono-sesquiterpenoid hydrocarbons; fraction 2 in thymol (73-83%); and fraction 3 contained thymol, carvacrol and terpinen-4-ol, with a different composition depending on the time of collection. Thymol-enriched fractions were the most active on both strains (IC50 20-22 μg/ml on D10 and 8-10 μg/ml on W2) and thymol was confirmed as mainly responsible for this activity (IC50 19.7 ± 3.0 and 10.6 ± 2.0 μg/ml on D10 and W2, respectively). The essential oil of S. thymbra L. showed also larvicidal and adulticidal activities. The larvicidal activity, expressed as LC50, was 0.15 ± 0.002; 0.21 ± 0.13; and 0.15 ± 0.09 μg/ml (mean ± sd) depending on the time of collection: before, during and after flowering, respectively.
  
  
  CONCLUSIONS
  This study provides evidence for the use of essential oils for treating malaria and fighting the vector at both the larval and adult stages. These findings open the possibility for further investigation aimed at the isolation of natural products with anti-parasitic properties.
authors: Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy. mario.dellagli@unimi.it
authors: Mario
authors: M
authors: Dell'Agli
authors: Cinzia
authors: C
authors: Sanna
authors: Patrizia
authors: P
authors: Rubiolo
authors: Nicoletta
authors: N
authors: Basilico
authors: Elisa
authors: E
authors: Colombo
authors: Maria M
authors: MM
authors: Scaltrito
authors: Mamadou Ousmane
authors: MO
authors: Ndiath
authors: Luca
authors: L
authors: Maccarone
authors: Donatella
authors: D
authors: Taramelli
authors: Carlo
authors: C
authors: Bicchi
authors: Mauro
authors: M
authors: Ballero
authors: Enrica
authors: E
authors: Bosisio
mesh_terms: D000818:Animals; D000852:Anopheles / Q000187:drug effects*; D000962:Antimalarials / Q000302:isolation & purification / Q000494:pharmacology*; D002853:Chromatography, Liquid; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D020128:Inhibitory Concentration 50; D007306:Insecticides / Q000302:isolation & purification / Q000494:pharmacology*; D007558:Italy; D007814:Larva / Q000187:drug effects; D019083:Mediterranean Region; D009822:Oils, Volatile / Q000302:isolation & purification / Q000494:pharmacology*; D021261:Parasitic Sensitivity Tests; D010946:Plants, Medicinal / Q000737:chemistry*; D010963:Plasmodium falciparum / Q000187:drug effects*; D016019:Survival Analysis
chemical_list: D000962:Antimalarials; D007306:Insecticides; D009822:Oils, Volatile