Sequential extraction approach for sustainable recovery of various hemp (Cannabis sativa L.) bioactive compounds

Abstract

Cannabis sativa L. known as industrial hemp manifests high capability in the manufacturing of valuable nutraceuticals with health benefits. This study was focused on investigation of chemical profile and bioactive potential of extracts isolated from three hemp varieties (Helena, Marina and Fedora 17). In addition, great attention was directed towards the use of green extraction techniques and maximum utilization of raw material. In that regard conventional (hydrodistillation – HD) and novel extraction techniques (microwave-assisted hydrodistillation – MWHD, supercritical fluid extraction – SFE and microwave-assisted extraction – MAE) were applied for isolating various fractions (essential oil, lipid extracts and liquid extract) with promising bioactive potential. Essential oils and lipid extracts were characterized regarding yield, terpenoid profile determined by GC-MS and in vitro antioxidant activity towards DPPH and ABTS + radicals. Furthermore, the content of two major cannabinoids was determined in plant material and in extract obtained by SFE. Sequential SFE technique allows obtaining lipid extracts in the first step of process as well as raffinates after SFE in the second step. MAE was applied for isolation of polyphenolic fraction from raw materials and SFE raffinates. Polyphenolic content was determined by spectrophotometric assays and UHPLC-Triple-quadrupole-MS. The results suggested that hemp is an excellent source of valuable terpenoid, cannabinoid and polyphenolic antioxidant agents, and further research should be focused on their utilization in dietary supplements and functional foods.