title: Actinobacillus pleuropneumoniae is impaired by the garlic volatile allyl methyl sulfide (AMS) in vitro and in-feed garlic alleviates pleuropneumonia in a pig model.
abstract: Decomposition products of ingested garlic are to a certain extent excreted via the lungs. If the supposed health-supporting capacities associated with garlic extend to these exhaled sulfurous compounds, they could have an effect on the course of pneumonia. In this study, the garlic-derived volatile allyl methyl sulfide (AMS) as a lead compound of volatile garlic metabolites was shown to exhibit an antibacterial effect against the pig pathogen Actinobacillus pleuropneumoniae serotype 9. AMS caused a delay in the appearance of the optical density-monitored growth of A. pleuropneumoniae in medium when compared to unaffected growth curves, yet without lowering the stationary phase yield at the concentration range tested. At 1.1mM, AMS impaired the in vitro growth rate of A. pleuropneumoniae serotype 9 by 8% compared to unimpeded growth. In an animal trial, a garlic-fed group of 15 pigs that received a diet with 5% garlic feed component and a control group of 15 pigs that received a diet without garlic were infected with A. pleuropneumoniae serotype 2 via an aerosol and subsequently followed for 4 days. At the day of the challenge, blood AMS in the garlic-fed group amounted to 0.32 ± 0.13 μM. A beneficial, alleviating effect of garlic on the course and severity of an A. pleuropneumoniae infection in pigs was indicated by the reduced occurrence of characteristic pleuropneumonia lesions (27% of the lungs affected in the garlic-fed group vs. 47% in the control group) and a near to significant (p=0.06) lower relative lung weight post mortem in the garlic-fed group.
authors.affiliation: Livestock Research, Animal Sciences Group of Wageningen UR, Edelhertweg 15, 8219 PH Lelystad, The Netherlands. petra.becker@wur.nl
authors.forename: Petra M
authors.initials: PM
authors.lastname: Becker
authors.forename: Piet G
authors.initials: PG
authors.lastname: van Wikselaar
authors.forename: Monique F
authors.initials: MF
authors.lastname: Mul
authors.forename: Arjan
authors.initials: A
authors.lastname: Pol
authors.forename: Bas
authors.initials: B
authors.lastname: Engel
authors.forename: Jan W
authors.initials: JW
authors.lastname: Wijdenes
authors.forename: Carola M C
authors.initials: CM
authors.lastname: van der Peet-Schwering
authors.forename: Henk J
authors.initials: HJ
authors.lastname: Wisselink
authors.forename: Norbert
authors.initials: N
authors.lastname: Stockhofe-Zurwieden
mesh_terms: D000189:Actinobacillus Infections / Q000178:diet therapy / Q000378:metabolism / Q000662:veterinary*; D016977:Actinobacillus pleuropneumoniae / Q000187:drug effects*; D000498:Allyl Compounds / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D000900:Anti-Bacterial Agents / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use; D004032:Diet; D005737:Garlic; D008168:Lung / Q000378:metabolism / Q000382:microbiology; D011001:Pleuropneumonia / Q000178:diet therapy / Q000378:metabolism / Q000382:microbiology / Q000662:veterinary*; D013440:Sulfides / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use; D013552:Swine; D013553:Swine Diseases / Q000178:diet therapy* / Q000378:metabolism / Q000382:microbiology
chemical_list: D000498:Allyl Compounds; D000900:Anti-Bacterial Agents; D013440:Sulfides; C077207:allyl methyl sulfide