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bioRxiv · 10.1101/2022.05.11.491040

A honey authenticity test by interphase emulsion reveals biosurfactant activity and biotechnology in the stingless bee nest of Scaptotrigona sp. 'Catiana' from Ecuador

Vit, P.
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Abstract

Bees are valuable pollinators of fruit trees and grasses. Honey is a medicinal food of plant and animal origin, with social impact for the wellbeing of bee keepers. The Neotropical apifauna has about 500 species of stingless bees (Meliponini). Commercial beekeeping with Apis mellifera underestimates the cultural legacy of meliponiculture, and both are affected by the presence of fake honeys in the market. Three alternative techniques (interphase emulsion, sensory analysis, and pollen residue) to nuclear magnetic resonance (NMR) were investigated to detect false honeys. One technique was based on an interphase emulsion test, which can be performed by beekeepers, farmers, housekeepers, professionals and consumers of honey in general. Another technique was sensory analysis by a tasting panel, and the third consisted on a palynological preparation with a simplified observation. Five genuine honeys produced by Apis mellifera, Geotrigona leucogastra, Melipona mimetica, Scaptotrigona sp., Tetragonisca angustula and a fake honey from Ecuador were analyzed. The honey authenticity test by interphase emulsion was fast and effective to detect fake honey (two phases), and genuine honeys (one and three phases). A further screening of was done in 51 Asian, Australia, European and Latinamerican honeys. Additionally the HATIE generated a new application as a test to detect unique biosurfactants in honey (HBT) of Scaptotrigona sp. Catiana (one phase) with potential microbial origin, and its entomological origin in this set of honeys. Catiana nests smell like Roquefort cheese, indicating a fungus association with this rural stingless bee highlighted by its distribution, productivity and the peculiarities described in this research, 80 years after its description as a new genus Scaptotrigona Moure, 1942. Paradoxically, this communication without microbiological analysis, infers the fungal presence in the nest of Scaptotrigona sp. by sensory observations different from the classic sensory evaluation of honey.

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Vit, P.. 2022-05-11. A honey authenticity test by interphase emulsion reveals biosurfactant activity and biotechnology in the stingless bee nest of Scaptotrigona sp. 'Catiana' from Ecuador. https://doi.org/10.1101/2022.05.11.491040

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