The Potential of Honey as a Prebiotic Food to Re-engineer the Gut Microbiome Toward a Healthy State

Honey has a long history of use for the treatment of digestive ailments. Certain honey types have well-established bioactive properties including antibacterial and anti-inflammatory activities. In addition, honey contains non-digestible carbohydrates in the form of oligosaccharides, and there is increasing evidence from in vitro, animal, and pilot human studies that some kinds of honey have prebiotic activity. Prebiotics are foods or compounds, such as non-digestible carbohydrates, that are used to promote specific, favorable changes in the composition and function of the gut microbiota. The gut microbiota plays a critical role in human health and well-being, with disturbances to the balance of these organisms linked to gut inflammation and the development and progression of numerous conditions, such as colon cancer, irritable bowel syndrome, obesity, and mental health issues. Consequently, there is increasing interest in manipulating the gut microbiota to a more favorable balance as a way of improving health by dietary means. Current research suggests that certain kinds of honey can reduce the presence of infection-causing bacteria in the gut including Salmonella, Escherichia coli, and Clostridiodes difficile, while simultaneously stimulating the growth of potentially beneficial species, such as Lactobacillus and Bifidobacteria. In this paper, we review the current and growing evidence that shows the prebiotic potential of honey to promote healthy gut function, regulate the microbial communities in the gut, and reduce infection and inflammation. We outline gaps in knowledge and explore the potential of honey as a viable option to promote or re-engineer a healthy gut microbiome

Characterizing the mechanism of action of an ancient antimicrobial, manuka honey, against pseudomonas aeruginosa using modern transcriptomics

Manuka honey has broad-spectrum antimicrobial activity, and unlike traditional antibiotics, resistance to its killing effects has not been reported. However, its mechanism of action remains unclear. Here, we investigated the mechanism of action of manuka honey and its key antibacterial components using a transcriptomic approach in a model organism, Pseudomonas aeruginosa. We show that no single component of honey can account for its total antimicrobial action, and that honey affects the expression of genes in the SOS response, oxidative damage, and quorum sensing. Manuka honey uniquely affects genes involved in the explosive cell lysis process and in maintaining the electron transport chain, causing protons to leak across membranes and collapsing the proton motive force, and it induces membrane depolarization and permeabilization in P. aeruginosa. These data indicate that the activity of manuka honey comes from multiple mechanisms of action that do not engender bacterial resistance. IMPORTANCE The threat of antimicrobial resistance to human health has prompted interest in complex, natural products with antimicrobial activity. Honey has been an effective topical wound treatment throughout history, predominantly due to its broad-spectrum antimicrobial activity. Unlike traditional antibiotics, honey-resistant bacteria have not been reported; however, honey remains underutilized in the clinic in part due to a lack of understanding of its mechanism of action. Here, we demonstrate that honey affects multiple processes in bacteria, and this is not explained by its major antibacterial components. Honey also uniquely affects bacterial membranes, and this can be exploited for combination therapy with antibiotics that are otherwise ineffective on their own. We argue that honey should be included as part of the current array of wound treatments due to its effective antibacterial activity that does not promote resistance in bacteria

Methylglyoxal (MGO) and dihydroxyacetone (DHA) levels in Australian <i>Leptospermum</i> honey samples.

<p>Methylglyoxal (MGO) and dihydroxyacetone (DHA) levels in Australian <i>Leptospermum</i> honey samples.</p

Hydroxymethylfurfural (HMF) concentrations in Australian <i>Leptospermum</i> honey collected between 1998 and 2007.

<p>Hydroxymethylfurfural (HMF) concentrations in Australian <i>Leptospermum</i> honey collected between 1998 and 2007.</p

Non-peroxide antibacterial activity of Australian <i>Leptospermum</i> honeys.

<p>Non-peroxide antibacterial activity of Australian <i>Leptospermum</i> honeys.</p

Relationship between methylglyoxal and non-peroxide activity in Australian <i>Leptospermum</i> honeys.

<p>Positive linear correlation between methylglyoxal (MGO) concentration and mean-squared non-peroxide activity (NPA) in Australian <i>Leptospermum</i> honey samples (n = 80) represented by diamond markers; green: MGO >800 mg/kg (NPA >20%), blue: MGO 260–800 mg/kg (NPA 10–20%), red: MGO <260 mg/kg (NPA <10%). Clover honey (purple triangle) served as a negative control with no detectable MGO or NPA, and New Zealand manuka honey (yellow square) and Medihoney^TM (orange circle) both served as the positive controls.</p