Bioactivity of Rosmarinus officinalis essentials oils against Apis mellifera, Varroa destructor and Paenibacillus larvae related to the drying treatment of the plant material

MAGGI M.; GENDE L.; RUSSO K.; FRITZ R.; EGUARAS M.

NATURAL PRODUCT RESEARCH

TAYLOR & FRANCIS AS

Lugar: London; Año: 2011 vol. 25 p. 397 - 406

1478–6419

The aims of this work were to compare the chemical composition, physicochemical properties and bioactivity of two Rosmarinus officinalis essential oils extracted from plant material with different drying treatment (in air conditions and in oven condition) against Apis mellifera, Varroa destructor and Paenibacillus larvae. Mite and bee LC50 was estimated using a complete exposure method test. Broth microdilution method was made in order to determine minimum inhibitory concentrations (MIC) of the essential oils against P. larvae. Physicochemical properties were similar in both essential oils but the percentage of components showed certain differences according with their drying treatment. Beta-myrcene and 1,8-cineole were the main constituent in the oils. The LC50 for complete exposure method at 24, 48 and 72 h was minor for mites exposed to R. officinalis essential oil dryed in oven conditions. MICs values were 700-800 ug/ml and 1200 ug/ml for R. officinalis dryed in air and oven conditions, respectively. The results reported in this research showed that oil toxicity against V. destructor and P. larvae differed depending on drying treatment of plant material previous essential oil distillation.