Health-Promoting Opportunities of Hemp Hull: The Potential of Bioactive Compounds.

Hemp hull is the outer coat of the hemp seed, derived from the plant Cannabis sativa L., Cannabaceae. While much attention has been paid to hemp seed for its oil, protein and micronutrient content, far less attention has been given to hemp hull, a side stream of hemp processing. Hemp hull is a source of bioactive compounds, dietary fiber, minerals as well as protein, lipids and carbohydrates. Of note, two bioactive compounds, n-trans-caffeoyltyramine and n-trans-feruloyltyramine have been identified in hemp hull as key bioactive compounds that support gut health, liver function and other physiological processes. Both of these compounds were identified as agonists of the transcription factor, hepatic nuclear factor-4 alpha which has been implicated in gene expression that governs gut permeability, factors associated with inflammatory bowel diseases, and hepatic lipid homeostasis. Additionally, the dietary fibers in hemp hull have been demonstrated to be novel prebiotics, which may further amplify hemp hull's effect on gut health and metabolic health. This review article summarizes the nutritional content of hemp hull, explores the physiological effects of bioactive compounds found in hemp hull, and identifies opportunities for further research on hemp hull for human health benefit.