Honey protein composition could offer powerful treatment applications, study says

New data on proteins found in honey could lead to new medicinal applications, according to a new study published in Journal of Natural Products.

Honey is a culinary staple that can be found in kitchens around the world. Humans have used honey throughout history, and its long shelf life and medicinal properties make it a unique, multipurpose natural product. Although it seems that a lot is known about it, surprisingly little is known about its proteins.

The highly valued food product has been touted as a natural remedy for wounds, respiratory infections, and other ailments. The product has been a target of counterfeiters, who sometimes add pollens or other substances to misrepresent the country of origin or the plant that the honey was made from. Thus, many studies have been conducted on the chemical makeup of honey, though not much has been done to identify its proteins. That's mostly because the proteins are present in tiny amounts, making analysis difficult. Researchers addressed this by conducting a proteomic analysis of several honeys.

The researchers analyzed the proteomes of thirteen different honeys, most of which came from the Czech Republic. Using mass spectrometry, the team identified known and previously unreported proteins and determined their amounts in each sample.

The major result is an expanded understanding of the proteins underlying honey’s antimicrobial properties, such as hymenoptaecin and defensin-1, glucose dehydrogenase isoforms, venom allergens, and other venom-like proteins, serine proteases and serine protease inhibitors, and a series of royal jelly proteins. In addition, researchers performed quantitative comparisons of all the proteins previously known or newly identified.

The honey proteins, determined using label-free nLC-MS/MS in which the same protein quantity was analyzed in one series, were found in relatively similar proportions, although eucalyptus honey differed most widely from the remaining honeys. Overall, the proteome analysis indicated that honeybees supply proteins to honey in a relatively stable ratio within each proteome, but total protein quantity can differ by approximately an order of magnitude in different honeys.

In addition, the results shed new light on various allergens that are present, and this knowledge could facilitate further investigations into the treatment of honey and bee allergies.