Activity of selected plant extracts against honey bee pathogen Paenibacillus larvae

Abstract

The present study focuses on the antibacterial activity of selected plant extracts against Paenibacillus larvae , the causal agent of American foulbrood disease of honey bees. A gas chromatography-mass spectrometry method was used to analyze six diethyl ether extracts of two white birch species, black poplar and common aspen buds, as well as n-hexane, diethyl ether, and methanol extracts of young twigs from downy and silver birches. Among the identified extract constituents were flavonoids, phenylpropenoids, triterpenoids, and glucosides. In spite of significant differences in qualitative and quantitative composition, all tested in vitro extracts demonstrated high anti-P. larvae activity at minimal inhibitory concentration levels between < 1.0 and 125 μg/mL. To examine the cause of such disparity, the anti-P. larvae activity of some individual constituents naturally present in plant extract compounds was determined. A higher susceptibility of P. larvae (ERIC I) to relatively poorly polar triterpenoid levels compared to polar compounds, flavonoids, and glucosides was demonstrated.

Application of the Natural Products NOZEMAT HERB and NOZEMAT HERB PLUS Can Decrease Honey Bee Colonies Losses during the Winter

“…Phenolics and flavonoids are commonly known as the largest phytochemical molecules with antioxidant properties from plants, which may prevent the degenerative effect (oxidative stress) from unbalanced concentration of reactive oxygen species (ROS) and reactive nitrogen species (RNS) [83][84][85]. Different researchers have confirmed the antibacterial activity of plant-derived compounds such as flavonoids, hydroxycinnamic, and phenolcarboxylic acids and their esters [86][87][88]. Finally, there is strong evidence that some phenolic compounds (p-coumaric acid) upregulate both detoxification genes and immunity genes.…”

Investigation of the effects of different disinfectant solutions on honey bees (Apis mellifera )

“…Extracts of parts of some plants such as root, aboveground parts or active substances obtained from these plants have long been used as antiviral, antibacterial (Paenibacillus larvae), fungicidal (Ascosphaera apis) and antiparasitic (against Varroa destructor) (37,38,39). The fact that the existing medicines used in the treatment of diseases have started to lose their effects over time caused researchers and drug companies to search for new types of drugs against these pathogens.…”

Immune-related gene expression in honey bee larva (Apis mellifera) exposed to plant extracts from Humulus lupulus with antimicrobial activity against Paenibacillus larvae

“…The use of natural extracts for the control of bee pathologies has been studied for years as a promising alternative to avoid the negative effects such as resistance and residues generated by synthetic ones (Miyagi et al 2000;Fuselli et al 2006Fuselli et al , 2009Flesar et al 2010;Pellegrini et al 2014, Chaimanee et al 2017Isidorov et al 2018;Giménez-Martínez et al 2019.…”