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Microbes & Immunity Hyphaene thebaica honey as a multitarget therapeutic product

Table 1. MIC and MBC values of tetracycline and kanamycin
Pathogenic microorganisms MIC (μg/mL) MBC (μg/mL) MBC/MIC ratio
Tetracycline Kanamycin Tetracycline Kanamycin Tetracycline Kanamycin
Pseudomonas aeruginosa 0.07 0.85 0.07 1.7 1 2
Staphylococcus aureus 0.02 0.11 0.04 0.11 2 1
Escherichia coli 0.03 0.47 0.06 0.94 2 2
Bacillus subtilis 0.78 0.39 1.56 0.78 2 2
Haemophilus influenzae 0.024 0.048 0.024 0.048 1 1
Streptococcus pneumoniae 1.56 0.78 3.12 1.56 2 2
Klebsiella pneumoniae 0.19 0.048 0.19 0.096 1 2
Abbreviations: MBC: Minimum bactericidal concentration; MIC: Minimum inhibitory concentration.
The assessment of MIC and MBC is universally Table 2. MIC and MBC of DH against various bacterial
acknowledged as an efficient and relatively cost-effective strains
method for evaluating the efficacy of various antimicrobial Pathogenic microorganisms MIC MBC MBC/
substances. DH demonstrated a favorable impact in (% w/w) (% w/w) MIC ratio
eradicating all examined bacterial strains. The MIC and Pseudomonas aeruginosa 0.39 0.78 2
MBC values of DH against the tested bacterial strains are
stated in Table 2. Klebsiella pneumoniae 0.096 0.096 1
Escherichia coli 0.024 0.048 2
The MIC values for the DH fluctuated between 0.19% Haemophilus influenzae 0.048 0.048 1
and 0.78% w/w for the three Gram-positive strains and
between 0.024% and 0.39% w/w for the four Gram- Streptococcus pneumoniae 0.78 1.56 2
negative strains. Among all the bacterial strains examined, Bacillus subtilis 0.38 0.76 2
E. coli was identified as the most susceptible with an MIC of Staphylococcus aureus 0.19 0.19 1
0.024% w/w, whereas S. pneumoniae was the most resistant Abbreviations: MBC: Minimum bactericidal concentration;
with an MIC of 0.78% w/w (Table 2). MIC: Minimum inhibitory concentration, DH: Doum honey.
The ratio of MBC to MIC can offer valuable insights into compounds. 52,53 Recent studies have also identified other
the nature of an antimicrobial agent, specifically whether antimicrobial components, such as the bee-derived peptide
it is bacteriostatic (halts bacterial growth) or bactericidal defensin-1, 5-hydroxymethylfurfural, and methylglyoxal,
(kills bacteria). If the MBC is not significantly greater than 54,55
the MIC (typically MBC/MIC ≤ 4), the antimicrobial agent as well as phenolic compounds, including flavonoids.
is deemed bactericidal, as it kills bacteria at concentrations Various varieties of honey from the Eastern
near the inhibitory concentration. Conversely, if the MBC Mediterranean region have demonstrated significant
is significantly higher than the MIC, the agent is classified inhibitory effects against both Gram-positive and
as bacteriostatic, as it primarily inhibits bacterial growth Gram-negative bacteria, including methicillin-resistant
rather than killing the bacteria. The DH’s ratio of MBC to S. aureus (MRSA) and methicillin-susceptible S. aureus
MIC against all examined bacteria consistently exhibited strains. However, compared to other types of honey,
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an approximate increase of up to two-fold over their MIC studies examining the bioactive properties of DH
values. This implies that DH honey exerts a bactericidal are limited. This study aimed to address this gap by
effect on all bacteria tested (Table 2). evaluating the phytochemical composition of DH, as
The MIC values for E. coli recorded in this study well as its antibacterial, antioxidant, anti-inflammatory,
were lower than the previously documented 0.52 – 1.0% and anticancer properties. The findings revealed broad-
range. 31,47-49 The antimicrobial effects of honey primarily spectrum antibacterial activity against all tested Gram-
stem from hydrogen peroxide, with additional contributions positive and Gram-negative bacteria. Honey has also been
from non-peroxide components such as phenolic acids and shown to be effective against drug-resistant pathogens,
flavonoids, which enhance its antibacterial and antioxidant including MRSA, drug-resistant hemolytic Streptococci,
properties. 50,51 Research indicates that these antibacterial and vancomycin-resistant Enterococci. 39,55 Furthermore,
effects can vary depending on the phytogeographical honey from various global regions has been found to
origin of the honey, influencing the production of various exhibit similar or even greater potency compared to

Volume 2 Issue 1 (2025) 82 doi: 10.36922/mi.4994