Bee Pollen Methanolic Extracts: Total Polyphenols Content And Antibacterial Activity

The aim of this work was to study the total phenolics content and antibacterial activity of bee pollen samples from different sources. Total polyphenols content was quantified according to the Folin-Ciocalteu spectrophotometric method using GA as standard and the results were expressed in terms of mg GAE/g pollen. Furthermore, the antibacterial activity of bee pollen samples from different sources were collected and investigated against multiple bacterial strains, as follows: five gram-positive Staphylococcus aureus ATCC 6538P, Bacillus cereus ATCC14579, Bacillus laterosporus 6932, Paenibacillus larvae 9820 and Paenibacillus alvei 13253, and four gram-negative Escherichia coli ATCC 10536, Pseudomonas aeruginosa ATCC 27853, Salmonella enteritidis ATCC 13076, Salmonella typhi ATCC 14028 and the yeast Candida albicans ATCC 90028. The samples with predominant pollen in Brassicaceae and Rosaceae possessed high levels of polyphenols content, whereas the samples predominant in Fabaceae showed lower levels of polyphenols. Regarding the antibacterial activity, our results revealed that most of the strains were inhibited by the 1/2 and 1/4 dilutions. The gram-negative bacteria and the yeast Candida albicans proved to be resistant to all bee pollen methanolic extracts. Our results showed that bee pollen samples have strong antibacterial activity against gram-positive bacteria.