In vitro growth-inhibitory effect of Brazilian plants extracts against Paenibacillus larvae and toxicity in bees.

In vitro growth-inhibitory effect of Brazilian plants extracts against Paenibacillus larvae and toxicity in bees. An Acad Bras Cienc. 2015 Jun 9;:0 Authors: Piana M, Brum TF, Boligon AA, Alves CF, Freitas RB, Nunes LT, Mossmann NJ, Janovik V, Jesus RS, Vaucher RA, Santos RC, Athayde ML Abstract American foulbrood (AFB) is a serious worldwide spreading disease in bees caused by Paenibacillus larvae. Plants extracts are known to decrease or inhibit the growth of these bacteria. The purpose of this study was to evaluate the antimicrobial activity of Calendula. officinalis, Cariniana domestica, and Nasturtium officinale extracts against the P. larvae and to evaluate the toxicity of the extracts in bees. In vitro activity against P. larvae of the extracts was evaluated by micro dilution method and the minimal inhibitory concentrations (MICs) were also determined. The concentrations used in the toxicity test were established based on the MIC values and by the spraying application method. The P. larvae was susceptible to the evaluated crude extract of C. officinalis and N. officinale. To C. domestica, only the ethyl acetate (EtAc) fraction and n-butanol (BuOH) fractions had activity against P. larvae. Toxicity analysis in bees showed no toxicity for N. officinale crude extract and for C. domestica BuOH fraction during 15 days of treatment, however, some deaths of bees occurred during the first three days of treatment with C. officinalis and...
Source: An Acad Bras Cienc - Category: Science Authors: Tags: An Acad Bras Cienc Source Type: research