Cannabidiol Content and In Vitro Biological Activities of Commercial Cannabidiol Oils and Hemp Seed Oils

Background: Hemp (Cannabis sativa L.) seed contains high contents of various nutrients, including fatty acids and proteins. Cannabidiol (CBD) is a non-psychoactive compound that can be extracted from C. sativa and used for treating epilepsy and pain. Industrial hemp products, including CBD and hemp seed oils, have become increasingly popular. Some products are marketed without a clear distinction between CBD and hemp seed oils. Herein, the CBD content and biological activities of commercial CBD and hemp seed oils were examined. Methods: CBD content was measured by high-performance liquid chromatography. For in vitro antioxidant activity determination, 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radical-scavenging assays were performed. Results: The CBD concentrations in the two CBD oil samples were 18.9 ± 0.5 and 9.2 ± 0.4 mg/mL. Of the seven hemp seed oil samples, six samples contained CBD in concentrations ranging from 2.0 ± 0.1 to 20.5 ± 0.5 µg/mL, but it was not detected in one sample. Antioxidant activity was observed in both CBD oil samples. Conclusions: The results indicate that (1) CBD content varied by hemp seed oil sample and that (2) antioxidant activity could be a useful landmark for discriminating CBD oils from hemp seed oils.