The potential of hemp roots, microgreens and leaves for human nutrition

Cannabis sativa L. has been utilised for food, fibre and medicine for millennia. However, historical legal constraints due to the presence of psychoactive cannabinoids have limited the use of the plant for human nutrition. For instance, in Australia, only dehulled hemp seeds and their derivatives have been available for human consumption since 2017, while the nutritional potential of other tissues remains overlooked. In this study, hemp leaves, roots and microgreens from cultivar HAN NE were analysed to determine their nutritional properties, including minerals, vitamins, terpenes, amino acids, and proximate data. Furthermore, cannabinoid contents were determined in target tissues, together with the expression of key genes involved in cannabinoid biosynthesis. Results highlighted the potential role of hemp leaves and microgreens in human nutrition, being able to provide a good source of protein, vitamin E, and various other essential micronutrients and minerals. The cannabinoid pathway was found to be active in microgreens and young leaves but not in roots, reflected by the measured cannabinoid concentrations in these tissues, which emphasised the importance of picking suitable cultivars for leaf and microgreens. Additionally, arsenic accumulation was observed in the roots, highlighting an important aspect of using roots for human nutrition.