Anti-viral properties of manuka honey are due to the presence of methylglyoxal (MG), an arginine directed glycating agent that modifies sites specifically present in the SARS-CoV-2 genome, thereby interfering with its replication and inhibiting the virus. In addition, manuka honey also exhibits strong anti-bacterial and anti-cancer properties. For now, manuka honey can be the ambrosia that may be consumed to boost the immunity against infections, including COVID-19 thereby promoting health.
In the current climate of COVID-19 pandemic especially when SARS‐CoV‐2 is mutating at an increasingly pace, giving rise to more infectious variants raising concern, it may be pertinent to explore and leverage resources that may have potential to boost immunity and contribute in combating against COVID-19 to reduce morbidity and mortality, thereby improving health.
In addition to consumption of Vitamin C and D to boost the immune system, honey, particularly Mānuka honey (a monofloral honey produced from the nectar of the mānuka tree, Leptospermum scoparium by European honey bees (Apis mellifera) is understood to be providing health benefits as immune booster in terms of fighting against infections. This article shall analyse, review and evaluate evidences from recent research with respect to manuka honey and its medicinal properties. Manuka honey is made from flowers of manuka tree that it is a native of Australia and New Zealand.
The major component of manuka honey that is responsible for its antibacterial and anti-viral properties is the presence of high amounts of methylglyoxal (MG). While MG is present in all types of honey at varying concentrations, it is present at a very high concentration in manuka honey. Higher MG results from conversion of dihydroxyacetone that is present in flowers of manuka tree at a high concentration. Higher the MG, higher the antibiotic effect. Manuka honey is rated using a rating factor known as UMF (Unique Manuka Factor). Higher the UMG, higher the antibiotic properties of manuka honey and higher its price.
It has been shown that MG, present in significant concentration in manuka honey, can act as an arginine-directed glycating agent, for selective toxicity to SARS-CoV-2. Sequence analysis of SARS-CoV-2 proteome revealed the presence of 5-fold enrichment of methylglyoxal modification sites in the SARS-CoV-2 proteome, compared to the human host – indicating selective toxicity of methylglyoxal to the virus (1). Manuka honey can interfere with the virus replication and inhibit the growth of enveloped virus (2). Anti-viral and immunomodulatory effects of manuka honey can also be ascribed to the presence of phenolic compounds that act as anti-oxidants (3). The presence of phenolic compounds, flavonoids such as quercetin may inhibit 3‐chymotrypsin‐like cysteine protease, an enzyme that plays an important role in viral life cycle (4), thereby exhibiting anti-viral effects of manuka honey.
The antibacterial property of manuka honey comes from the presence of Hydrogen peroxide, low pH and high sugar content, characteristics that are found on other honey types as well. The antibacterial effect of manuka honey has been demonstrated by significantly reducing MRSA cell viability in a biofilm (5). This was due to the significantly reduced expression of genes encoding laminin- (eno), elastin- (ebps) and fibrinogen binding protein (fib), and icaA and icaD, involved in biosynthesis of polysaccharide intercellular adhesin in both weakly and strongly adhering strain, compared to the control. Manuka honey also exhibited activity against Escherichia coli O157:H7 in biofilms (6) as well as bactericidal and anti-spore formation activity against Clostridioides difficile (7).
In addition, manuka honey has also been shown to exhibit anti-cancer activity. This was demonstrated by the ability of manuka honey to induce apoptosis in a cancer cell line by maintaining high permeability of hydrogen peroxide against intracellular reactive oxygen species (8) . The antitumor effect of manuka honey is due to inhibitory effects on the inflammatory and oxidative stress signalling as well as inhibition of proliferation and metastasis component activities (9).
There seems to be enough evidence to suggest that consumption of honey, especially manuka honey may help people improve their immunity due to the anti-viral and anti-bacterial properties caused by the presence of MG. In addition, consumption of manuka honey as part of life-style management may also help in cancer prevention. Is it worthwhile to surmise that manuka honey is a panacea for all ills inflicting mankind? Time will tell and the answer will lie in the analyses of data generated from more studies on consumption of manuka honey. However, for now, manuka honey seems to be the ambrosia that may be consumed for its medicinal properties to prevent severity of bacterial and viral infections including COVID-19.
- Al-Motawa, Maryam and Abbas, Hafsa and Wijten, Patrick and Fuente, Alberto de la and Xue, Mingzhan and Rabbani, Naila and Thornalley, Paul, Vulnerabilities of the SARS-CoV-2 Virus to Proteotoxicity — Opportunity for Repurposed Chemotherapy of COVID-19 Infection. Available at SSRN: https://ssrn.com/abstract=3582068 or http://dx.doi.org/10.2139/ssrn.3582068
- Hossain K., Hossain M., et al., 2020. Prospects of honey in fighting against COVID-19: pharmacological insights and therapeutic promises. Heliyon 6 (2020) e05798. Published: December 21, 2020. DOI: https://doi.org/10.1016/j.heliyon.2020.e05798
- Al-Hatamleh M., Hatmal H., et al., 2020. Antiviral and Immunomodulatory Effects of Phytochemicals from Honey against COVID-19: Potential Mechanisms of Action and Future Directions. Molecules 2020, 25(21), 5017. Published: 29 October 2020. DOI: https://doi.org/10.3390/molecules25215017
- Lima WG., Brito J., and Nizer W., 2020. Bee products as a source of promising therapeutic and chemoprophylaxis strategies against COVID‐19 (SARS‐CoV‐2). Phytotherapy Research. First published: 18 September 2020. DOI: https://doi.org/10.1002/ptr.6872
- Kot B., Sytykiewicz H., et al., 2020. Effect of manuka honey on biofilm-associated genes expression during methicillin-resistant Staphylococcus aureus biofilm formation. Nature. Scientific Reports volume 10, Article number: 13552 (2020) Published: 11 August 2020. DOI: https://doi.org/10.1038/s41598-020-70666-y
- Kim S., and Kang S., 2020. Anti-Biofilm Activities of Manuka Honey against Escherichia coli O157:H7. Food Science of Animal Resources. 2020 Jul; 40(4): 668–674. DOI: https://doi.org/10.5851/kosfa.2020.e42
- Yu L., Palafox-Rosas R., et al., 2020. The Bactericidal Activity and Spore Inhibition Effect of Manuka Honey against Clostridioides Difficile. Antibiotics 2020, 9(10), 684; DOI: https://doi.org/10.3390/antibiotics9100684
- Martinotti S., Pellavio G., et al., 2020. Manuka Honey Induces Apoptosis of Epithelial Cancer Cells through Aquaporin-3 and Calcium Signaling. Published: 27 October 2020. Life 2020, 10(11), 256; DOI: https://doi.org/10.3390/life10110256
- Talebi M., Talebi M., et al., 2020. Molecular mechanism-based therapeutic properties of honey. Biomedicine & Pharmacotherapy Volume 130, October 2020, 110590. DOI: https://doi.org/10.1016/j.biopha.2020.110590