The beeswax processing by‐product: a potential antibacterial ingredient for food and nutraceutical applications

Abstract

SummaryThe purification of raw beeswax by melting produces a semi‐solid beeswax by‐product (BBR) composed by honey, resins and other constituents that is usually considered as a waste. In this article, the chemical characterisation of BBR is reported, with the aim to valorise this by‐product following the principles of the circular economy. Carbohydrates, hydrocarbons and minerals were among the main constituents. Flavonoids and phenolic acids represent 1.5% of the BBR, and their qualitative profile resembles the propolis. To assess its potential usefulness, the BBR was tested against gram‐positive and gram‐negative bacteria of clinical interest, and results were compared with the raw propolis. Klebsiella pneumoniae and Salmonella enterica were inhibited at concentrations ≥ 0.001 mg mL−1, while Enterococcus faecalis and methicillin‐resistant Staphylococcus aureus from 0.01 mg mL−1. Only BBR was active on Pseudomonas aeruginosa. Below the concentration of 1 mg mL−1, no significant toxicity on Caco2 cells was observed. These results indicate that the BBR presents a polyphenol composition similar to propolis and a significant antibacterial activity. Thus, on the basis of these results, we suggest that the BBR can represent a sustainable alternative to propolis as food preservative or nutraceutical.