Investigating the therapeutic potential of Australian honey as a prebiotic and anti-inflammatory to improve gut health

Abstract

The gut microbiome is a complex microbial community that plays a critical role in host health. Diet is a major determinant of its composition and function, while dysbiosis is associated with intestinal inflammation and numerous chronic diseases. Australian honey has emerged as a potential functional food due to its complex carbohydrate content and reported antimicrobial, prebiotic and anti-inflammatory properties.

This thesis investigated the antibacterial, antioxidant, prebiotic and anti-inflammatory potential of 56 Australian honeys from diverse floral sources using in vitro, ex vivo and in vivo models. Australian honeys exhibited minimal antibacterial activity under anaerobic conditions, indicating little potential to adversely affect beneficial gut bacteria, while antioxidant capacity differed significantly between floral types. Ex vivo studies demonstrated that all honeys promoted Lactobacillaceae growth and enhanced suppression of opportunistic pathogens in mixed faecal cultures.

In vivo, Australian honey increased the abundance of beneficial taxa, including members of the Lactobacillaceae and Muribaculaceae families, in mice fed a standard chow diet. Following western diet-induced gut microbiome restructuring, honey promoted alternative carbohydrate-metabolising taxa rather than restoring those reduced by the diet. In a dextran sodium sulphate (DSS) model of colitis, honey reduced histopathological indicators of inflammation and promoted immune phenotypes associated with inflammation resolution.

Collectively, these findings demonstrate that Australian honey possesses antimicrobial, antioxidant, prebiotic and anti-inflammatory properties that support its potential to beneficially modulate the gut microbiome and attenuate intestinal inflammation. These results provide a foundation for future investigations into Australian honey as a functional food for gastrointestinal health.