Subcritical water extraction of antioxidants from aerial parts of hemp (Cannabis sativa L.)

Abstract

Hemp (Cannabis sativa L.) is an herbaceous annual dioecious plant recognizable for their characteristic spiky leaves from the Cannabaceae family. Cannabis sativa L. is a plant with more than 480 compounds which can be divided into diverse phytochemical classes such as cannabinoids, terpenoids, flavonoids, noncannabinoid phenols, hydrocarbons, nitrogen-containing compounds, carbohydrates. The most studied class is the cannabinoids, but the presence of other bioactive components, especially polyphenols is signifiifcant. The extraction of polyphenolic compounds of hemp was carried out by subcritical water. The effects of different extraction temperatures (120⁰C – 220⁰C) on the extraction yield, total phenol content, total flavonoid content, and antioxidant activity, determinate by DPPH method, and reductive capacity, were investigated. Extraction time was 10 minutes. In obtained extracts content of total phenols was in the range from 1.00 to 2.26 mg GAE/mL extract, the content of total flavonoids was in the range from 0.48 to 0.81 mg CE/mL extract. Antioxidant activity was from 0.0006 to 0.0017 ml extract/ml reaction mixture, while the reductive capacity was from 0.0014 to 0.0058 ml extract/ml reaction mixture.