BCCM/MUCL realised a yeast diversity study in collaboration with the Beekeeping Research and Information Centre CARI, Louvain-la-Neuve, Belgium. The study showed a succession of different genera during bee bread maturation. Representative strains are available at BCCM/MUCL.
Starmerella and other yeasts from bee bread available at BCCM/MUCL
Bee nutrition depends on pollen as source of protein and other nutrients. Honey bees process and store pollen that then ferments by the action of lactic acid bacteria and yeasts. The resulting bee bread is marked by a changed amino acid profile and a lowered pH.
165 samples and 252 identified yeast isolates showed that the initially high yeast abundance, dominated by members of the genus Starmerella, decreased rapidly during bee bread storage towards a low density of Zygosaccharomyces species. Starmerella (Candida) apis, a rarely isolated species, was the most frequent and abundant species in fresh bee bread. Yeasts from the bee’s honey stomach and from pollen pellets were dominated by Metschnikowia species.
The apparent specialisation of different yeast genera, each in different phases of bee bread maturation or in its components, indicates a non-random distribution. More work is needed to clarify the source, potential role, and possible geographical and seasonal incidence of the yeast species that are associated with fresh bee bread to better understand honey bee nutrition. Yeasts of the genus Starmerella are a promising study object for ecological studies and concerning their potential to produce sophorolipids, surface active compounds with emulsifying activity. The deposited strains MUCL 56082- MUCL 56139 & MUCL 56143 should promote such research.
The resulting paper on the ‘Specialisation of yeast genera in different phases of bee bread maturation’ was published in the open access MDPI journal Microorganisms (ISSN 2076-2607), section Microbial Biotechnology, special issue on Non-Conventional Yeasts.
https://www.mdpi.com/2076-2607/8/11/1789/htm
More information: heide-marie.daniel@uclouvain.be