Green extraction of hemp (Cannabis sativa L.) using microwave method for recovery of three valuable fractions (essential oil, phenolic compounds and cannabinoids): a central composite design optimization study

What if the waste from hemp essential oil production could be turned into a goldmine of bioactive compounds? A new study shows how a simple, solvent-free microwave method can extract not just oil, but also valuable phenolics and cannabinoids from the same plant.

Hemp essential oil is a treasure trove, but the conventional extraction methods leave behind two overlooked by-products: an aqueous residue rich in phenolics and a spent biomass full of potential cannabinoids. This study, using a central composite design, optimized microwave-assisted extraction (MAE) without solvents, varying power, time, and water content to maximize yields of all three fractions simultaneously. The team characterized the products for yield, chemical profile, and antioxidant power. The aqueous residue showed impressive α-glucosidase inhibition and superoxide radical scavenging, with modest anti-glycation activity but no lipase inhibition. The spent biomass, however, had no significant biological activity. This almost waste-free approach demonstrates a sustainable way to valorize hemp, turning industrial by-products into potential ingredients for pharmaceuticals, cosmetics, and nutraceuticals.

Key Points

• Solvent-free microwave extraction optimizes hemp oil, phenolics, and cannabinoids.
• Aqueous residue shows strong α-glucosidase inhibition and antioxidant activity.
• Almost waste-free valorization of hemp by-products for pharma and cosmetics.