title: The role of diallyl sulfides and dipropyl sulfides in the in vitro antimicrobial activity of the essential oil of garlic, Allium sativum L., and leek, Allium porrum L.
abstract: The in vitro antibacterial activity of essential oils (EOs) obtained from fresh bulbs of garlic, Allium sativum L., and leek, Allium porrum L. ( Alliaceae), was studied. A. sativum (garlic) EO showed a good antimicrobial activity against Staphylococcus aureus (inhibition zone 14.8 mm), Pseudomonas aeruginosa (inhibition zone 21.1 mm), and Escherichia coli (inhibition zone 11.0 mm), whereas the EO of A. porrum (leek) had no antimicrobial activity. The main constituents of the garlic EO were diallyl monosulfide, diallyl disulfide (DADS), diallyl trisulfide, and diallyl tetrasulfide. The EO of A. porrum was characterized by the presence of dipropyl disulfide (DPDS), dipropyl trisulfide, and dipropyl tetrasulfide. The antimicrobial activities of the DADS and DPDS were also studied. The results obtained suggest that the presence of the allyl group is fundamental for the antimicrobial activity of these sulfide derivatives when they are present in Allium or in other species (DADS inhibition zone on S. aureus 15.9 mm, P. aeruginosa 21.9 mm, E. coli 11.4 mm).
authors.affiliation: Dipartimento di Chimica Farmaceutica, University of Pisa, Via Bonanno 33, 56126, Pisa, Italy. sergio.casella@ymail.com
authors.forename: Sergio
authors.initials: S
authors.lastname: Casella
authors.forename: Michele
authors.initials: M
authors.lastname: Leonardi
authors.forename: Bernardo
authors.initials: B
authors.lastname: Melai
authors.forename: Filippo
authors.initials: F
authors.lastname: Fratini
authors.forename: Luisa
authors.initials: L
authors.lastname: Pistelli
mesh_terms: D000490:Allium / Q000737:chemistry*; D000498:Allyl Compounds / Q000737:chemistry / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004220:Disulfides; D004926:Escherichia coli / Q000187:drug effects; D008401:Gas Chromatography-Mass Spectrometry; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology*; D010938:Plant Oils / Q000737:chemistry / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects; D013440:Sulfides / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000498:Allyl Compounds; D000900:Anti-Bacterial Agents; D004220:Disulfides; D009822:Oils, Volatile; D010938:Plant Oils; D013440:Sulfides; C042577:diallyl trisulfide; C028009:diallyl disulfide; C038491:allyl sulfide; C431585:diallyl tetrasulfide