<abstract xmlns="http://www.w3.org/1999/xhtml"><p> Paenibacillus larvae is the causative agent of American Foulbrood (AFB ), a severe disease that affects the larvae of the honeybees. The use of plant extracts are considered to be an alternative way of controlling the disease. In this study, the in vitro antimicrobial activity of Buddleja thyrsoides Lam. against the Paenibacillus species, including P. larvae, was evaluated. In Mueller-Hinton broth, the minimal inhibitory concentration (MI C) was assessed using the microdilution method. All Paenibacillus species were sensitive to the crude extract and the fractions of B. thyrsoides. The ethyl acetate (EA ) fraction showed a better result with MI C values of 1.68 - 3.36 mg/mL, followed by butanolic (BU) (MI C = 2.18 - 6.54 mg/mL), dichloromethane (DCM) (7.40 - 14.80 mg/mL), and crude extract (CE) (7.51 - 16.90 mg/mL). The toxic effect of the CE and fractions of B. thyrsoides against bees were also evaluated using the spraying application method with the same concentrations of MI Cs. Bee mortality was evident in treatment with DCM fractions only, while CE, EA , and BU extracts showed no toxic effects after 15 days of observation. Furthermore, phenolic acids, tannins, and flavonoids were identified and quantified by highperformance liquid chromatography (HPLC), and may be partially responsible for the antimicrobial properties observed. These results show, for the first time, that B. thyrsoides might be a natural alternative for the prevention/control of AFB .</p></abstract>

Paenibacillus larvae is the causative agent of American Foulbrood (AFB ), a severe disease that affects the larvae of the honeybees. The use of plant extracts are considered to be an alternative way of controlling the disease. In this study, the in vitro antimicrobial activity of Buddleja thyrsoides Lam. against the Paenibacillus species, including P. larvae, was evaluated. In Mueller-Hinton broth, the minimal inhibitory concentration (MI C) was assessed using the microdilution method. All Paenibacillus species were sensitive to the crude extract and the fractions of B. thyrsoides. The ethyl acetate (EA ) fraction showed a better result with MI C values of 1.68 - 3.36 mg/mL, followed by butanolic (BU) (MI C = 2.18 - 6.54 mg/mL), dichloromethane (DCM) (7.40 - 14.80 mg/mL), and crude extract (CE) (7.51 - 16.90 mg/mL). The toxic effect of the CE and fractions of B. thyrsoides against bees were also evaluated using the spraying application method with the same concentrations of MI Cs. Bee mortality was evident in treatment with DCM fractions only, while CE, EA , and BU extracts showed no toxic effects after 15 days of observation. Furthermore, phenolic acids, tannins, and flavonoids were identified and quantified by highperformance liquid chromatography (HPLC), and may be partially responsible for the antimicrobial properties observed. These results show, for the first time, that B. thyrsoides might be a natural alternative for the prevention/control of AFB .

Potential Use of Buddleja Thyrsoides for the Control and Prevention of American Foulbrood Disease in Honey Bees

Departamento de Farmácia Industrial, Universidade Federal de Santa Maria, CEP 97105-900, Santa Maria, RS, Brazil

UNIFRA - Centro Universitário Franciscano Rua dos Andradas, 1614 - Centro, Santa Maria, RS, 97010-032, Brazil

Journal of Apicultural Science

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Paenibacillus larvae is the causative agent of American Foulbrood (AFB ), a severe disease that affects the larvae of the honeybees. The use of plant extracts...

Potential Use of Buddleja Thyrsoides for the Control and Prevention of American Foulbrood Disease in Honey Bees

Publié en ligne: 11 déc. 2014

Pages: 71 - 78

Reçu: 29 juil. 2014

Accepté: 12 nov. 2014

DOI: https://doi.org/10.2478/jas-2014-0023

Mots clés
Antibacterial activity, bee survival, Buddleja thyrsoides, HPLC, Paenibacillus larvae

© by Aline A. Boligon

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Potential Use of Buddleja Thyrsoides for the Control and Prevention of American Foulbrood Disease in Honey Bees

Publié en ligne: 11 déc. 2014

Pages: 71 - 78

Reçu: 29 juil. 2014

Accepté: 12 nov. 2014

DOI: https://doi.org/10.2478/jas-2014-0023

Mots clésAntibacterial activity, bee survival, Buddleja thyrsoides, HPLC, Paenibacillus larvae

© by Aline A. Boligon

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Mots clés
Antibacterial activity, bee survival, Buddleja thyrsoides, HPLC, Paenibacillus larvae