Bee Bread Exhibits Higher Antimicrobial Potential Compared to Bee Pollen

Abstract

This study aimed at investigation of the antimicrobial potential of ethanolic extracts of bee bread (BB) and bee pollen (BP) and suspensions of these products in MHB (Mueller Hinton Broth). We covered 30 samples of BP and 19 samples of BB harvested in Polish apiaries. Slightly lower activity was observed against Gram-negative bacteria compared to Gram-positive staphylococci. BB extracts exhibited higher inhibitory potential with minimum inhibitory concentration (MIC) values in the range from 2.5 to 10% (v/v) against Staphylococcus aureus ATCC 25923 and ATCC 29213. Most active BB extracts, namely, BB6, BB11 and BB19, effectively inhibited growth of clinical isolates of S. aureus (n = 9), including MRSA (methicillin resistant Staphylococcus aureus) strains (n = 3) at concentrations ranging from 2.5 to 5.0% (v/v). Minimal bactericidal concentration (MBC) values were in the same range of concentrations; however, a shift from 2.5 to 5.0% (v/v) was observed for some products. The most active BP extracts inhibited the growth of reference strains of S. aureus at a concentration of 5% (v/v). Up to the concentration of 20% (v/v) three and seven BP extracts were not able to inhibit the growth of S. aureus ATCC 29213 and S. aureus ATCC 25923 respectively. The growth of staphylococci was also importantly inhibited in suspensions of the products in MHB. No correlation between phenolic content and antimicrobial activity was observed.

Biological Properties of Bee Bread Collected from Apiaries Located across Greece

“…The variability of biological properties could be attributed to differences in the botanical and geographical origin of the samples as well as to differences regarding the extraction methods used. Another possible explanation could be that most published studies on BB antimicrobial activity test but few samples (1–5) [ 1 ] with the notable exception of the very recent study by Pelka et al [ 49 ] on Polish BB. In order to correlate biological properties with botanical origin, a sufficient number of samples is required to represent both botanical diversity and geographical distribution.…”

“…The antimicrobial activity of bee bread was generally attributed to diverse phytochemicals, mainly polyphenols, fatty acids, phytosterols, and presumably microbial metabolites [ 1 ]. Pelka et al [ 49 ] reported no correlation between the phenolic content and antimicrobial activity of Polish BB. In accordance, this study does not report a statistically significant correlation between antibacterial and antioxidant activity or the total content of phytochemicals such as polyphenols or flavonoids ( Table 4 ).…”

“…Nevertheless, in health-food markets, BB is significantly less available than pollen, which is much easier to collect from the bee hive. The last few years' research regarding antimicrobial and antioxidant BB properties has started to attract attention [1,[49][50][51][52].…”

Bee Bread as a Promising Source of Bioactive Molecules and Functional Properties: An Up-To-Date Review

“…In a study conducted by Didaras et al [ 84 ], it was reported that the aqueous extract of Greek bee bread was effective against Gram-positive bacteria (MIC values ranging between 3.9 mg/mL and 48 mg/mL) and against Gram-negative bacteria (MIC values ranging between 7.8 mg/mL and 90.4 mg/mL). It has also been shown that bee bread ethanolic extracts (70%, 95%, 80%, and 50%) have strong antibiotic activity against Gram-positive bacteria ( Bacillus cereus , Clostridium perfringens, Staphylococcus aureus, Bacillus Subtilis, methicillin-susceptible Staphylococcus aureus, Staphylococcus epidermidis, and Listeria monocytogene ), Gram-negative bacteria ( Haemophilus influenza, Klebsiella pneumonia, Salmonella enteric, Escherichia coli, Shigella, Salmonella typhi , and Pseudomonas aeruginosa )and fungi ( Candida albicans, Aspergillus niger , Candida glabrata, Candida tropicalis , Aspergillus clavatus, Aspergillus flavus, Aspergillus versicolor, Penicillium expansum, Penicillium chrysogenum, and Penicillium griseofulvum ) [ 52 , 85 , 86 , 87 , 88 ].…”

Therapeutic Effects of Bee Bread on Obesity-Induced Testicular-Derived Oxidative Stress, Inflammation, and Apoptosis in High-Fat Diet Obese Rat Model

“…Bee bread also has several health benefits including antioxidant [ 4 , 5 ], anti-inflammatory [ 6 ], anti-apoptotic [ 7 ], antimicrobial [ 3 , 8 ], anticancer [ 9 ], and immunological effects [ 10 , 11 ] on various tissues. Its effects on the male reproductive system cannot be over emphasised; our previous study has revealed that concurrent administration of a high-fat diet and 0.5 g/kg bee bread for twelve weeks showed protective effects against testicular oxidative stress, inflammation, and apoptosis in rats [ 12 ].…”