Study of the antimicrobial activity of Lebanese honey Zaher Mshakal and its effect on the shelf-life of Ashta

Abstract

This study is specifically concerned with the antimicrobial activity of the Lebanese honey Zaher Mshakal and its effect on the shelf life of ashta. The sample of honey Zaher Mshakal was collected from a local beekeeper in Fawar village, North Lebanon. The honey was harvested in August 2015. An extraction of an antimicrobial peptide, bee defensin-1, was applied using acid extraction. The extract was identified using HPLC. Then, the MIC of the extract was measured against Escherichia coli, Salmonella enterica, Staphylococcus aureus, and Pseudomonas aeruginosa. The sample of ashta prepared from UHT milk purchased from a local market in Tripoli was mixed with the extract and examined to determine the growth of total aerobes, total psychrotrophs, yeast and molds, Escherichia coli, Staphylococcus aureus, and Salmonella spp through 7 days experiment. The results of the extraction reveal a low quantity of white powder which supposed to be the antimicrobial peptide, bee defensin-1. HPLC chromatograms did not permit to confirm that the extract is bee defensin-1. However, the extract showed a great antimicrobial activity with MIC of 198.125 g/ml against all the microorganisms tested. The 7 days examination of the growth of microorganisms in ashta mixed with the extract prove a great inhibition of microorganisms with Shigella spp, Enterobacteriaceae microorganisms detected, and Escherichia coli being the most sensitive against the extract than yeast and molds and Staphylococci. On the basis of the results of this study, it can be concluded that the extract has a definite antimicrobial activity against a broad range of microorganisms and it can be used in further studies in order to extend the shelf life of ashta. However, further experiments are needed to identify the extract and determine the presence of bee defensin-1.