# A Novel Biosensor for the Early Detection of Aethina tumida via Kodamaea ohmeri in Honeybee Colonies

## TL;DR

A new biosensor detects the small hive beetle in honeybee colonies by identifying a yeast it carries, helping beekeepers act early to protect bees and agriculture.

## Contribution

A novel QCM-based biosensor for early detection of Aethina tumida via its symbiotic yeast Kodamaea ohmeri in honey samples.

## Key findings

- The biosensor uses a gold-plated quartz crystal to detect a specific peptide from Kodamaea ohmeri in honey.
- Preliminary results show the biosensor can identify infestations, enabling timely colony management.
- Further improvements are needed to enhance detection thresholds and robustness for field use.

## Abstract

This work presents a biosensor for the early detection of the small hive beetle Aethina tumida in honeybee colonies. The biosensor targets the symbiotic yeast Kodamaea ohmeri, associated with the beetle, which has been infesting hives and killing Apis mellifera. Based on QCM technology, this sensor detects, in honey samples, a peptide from Kodamaea ohmeri. It is a highly specific and sensitive device suitable for field tests to identify the infestation. Further studies are foreseen to improve the thresholds and robustness of this detection in an effort to protect sustainable agriculture and biodiversity.

Aethina tumida, commonly known as the small hive beetle, poses a threat to honeybee populations, particularly Apis mellifera, across several European regions. Originating in sub-Saharan Africa, there is a risk of the infestation spreading from Calabria, a region in the south of Italy. The essential role played by Apis spp. in pollination biodiversity preservation, agricultural productivity, and the overall economy is related to the dangers posed by the invasion of Aethina tumida. Current detection methods often fail to identify infestations early, leading to significant colony losses. We focused on creating a biosensor to improve the detection of Kodamaea ohmeri, a recently identified yeast that coexists symbiotically with Aethina tumida. The biosensor was designed to exploit the highly sensitive quartz crystal microbalance to identify a specific peptide linked to Kodamaea ohmeri in honey specimens. Its gold-plated surface over quartz was functionalized with an antibody effective in recognizing the peptide associated with Kodamaea ohmeri, a potential warning for detecting Aethina tumida. Preliminary results support the possibility of using such biosensor technology to detect infestation and enhance colony management techniques for honeybees, enabling beekeepers to implement prompt and focused treatments. In addition, reducing the size and cost of these biosensors and offering user training would be very helpful in having them used in beekeeping.