During the last years a steady and increasing interest on probiotic microorganisms generally took place, including several and diverse research activities on their potential applications.
The importance of probiotic microorganisms was initially mainly devoted to human nutrition but then novel interesting perspectives were also introduced for zootechnical applications. Currently aquaculture represents an emerging area where probiotics can lead to innovative results but beekeeping can also benefit of biological approaches in order to improve both bee health and quality of final products (honey, propolis, royal jelly).
In this work samples of bees, honey, brood, and other material were collected from an experimental apiary located in the area of Caprarola (Viterbo, Italy). These samples were used for enrichment cultures that led to the isolation of 45 strains as representatives of the existing microflora. Following physiological (growth rate, acidic pH tolerance) and taxonomic (BIOLOG system) analyses, 6 strains showing probiotic traits were selected and tested in vitro to evaluate their antagonistic activities against Paenibacillus larvae and Paenibacillus alvei.
Some of these strains particularly showed inhibitory capacities versus both antagonistic bacteria, so they may represent potential candidates for the biological treatment of such pathogens. Further experimental trials were also performed in order to evaluate the survival of selected probiotic strains after cryo-lyophilization, under different storage temperatures and with diverse cryo-preservatives.
The results obtained in this work can be considered as valuable preliminary data, useful to introduce probiotics into the world of beekeeping. It is expected, as far as regards veterinary and microbiological issues, an increasing interest of pharmaceutical industries and beekeepers into the potential development of probiotic in vivo applications.
Bee diseases (particularly the ones caused by bacteria and fungi) are becoming a serious problems because the unavailability of specific drugs and also because the increasing amount of bee products of low quality imported from developing countries. In Italy preliminary current indications were reported claiming the disappearance of 30-50% bee population due also to undefined pesticides.
The exploitation of beneficial microorganisms to assure the overall quality of beekeeping is then desirable and applied microbiological initiatives are expected to be pursued to accomplish the task.