Control of Ascosphaera apis and Paenibacillus larvae by the use of essential oils for obtaining beehive products without toxic residues

BAILAC, PEDRO; GENDE, LIESEL; GASCÓN ALEJANDRO; FRITZ, ROSALIA; PONZI, MARTA; EGUARAS, MARTIN

Molecular Medicinal Chemistry

Año: 2006 vol. 11 p. 1 - 2

1666-888X

American foulbrood, a disease caused by the spore-forming bacterium Paenibacillus larvae, as well as chalkbrood disease, caused by the spore-forming ascomycete fungus, Ascosphaera apis,  are two microbial pathologies that affect honeybee brood (Apis mellifera) producing severe damages in apiarian producers. In this work in vitro behaviour of essential oils from wild plant species collected in San Luis has been studied, e.g., Tessaria absinthioides, Baccharis coridifolia, Hetheroteca latifolia, Aloysia gratissima, Eupatorium patens, Lippia juneliana, L. integrifolia and L. turbinata against Ascosphaera apis. Also essential oils of culinary aromatic plants were studied, e.g., Syzygium aromaticum (clove), Cinnamomum zeylanicum (cinnamon), Thymus vulgaris (thyme), Pimpinella  anisum (anise) and Foeniculum vulgare (fennel) against Paenibacillus larvae subsp. larvae. Oils that produced the highest inhibition halo against Ascosphaera apis were those of the genus Lippia 75% inhibition, Tessaria absinthioides and Hetheroteca latifolia 62.5% inhibition. Aloysia gratissima 50% inhibition with regard to the ketoconazol (1 mg/ml)  control. Baccharis coridifolia and Eupatorium  patens didn´t show any inhibition halo. MIC values  were 250-300 ppm for clove oil, 25-50 ppm for  cinnamon oil, 150 ppm for thyme, 300 ppm for  anise and 250 ppm for fennel essential oil.