PHYTOCHEMICAL COMPOSITION AND BIOLOGICAL ACTIVITY OF TWO EXTRACTS FROM A CHINESE ACCESSION OF CANNABIS SATIVA L.

The aim of this study was to examine the composition of two different extracts obtained from dried flowering tops of a new Chinese accession (G-309) of Cannabis sativa L. (Cannabaceae) with Δ9-THC content <0.2%, evaluating also their antioxidant and antimicrobial properties. Cannabis flowering tops dried as such and after hydrodistillation of the essential oil were extracted with acidic hexane producing the cannabis hexane extract 1 (CHE1) and the cannabis hexane extract 2 (CHE2) respectively. HPLC-DAD analysis highlighted a high titer of both acid and neutral phytocannabinoids1. However, an-in deep phytochemical profile elucidation by GC-MS analysis leaded to identification of 73 and 43 compounds into CHE1 and CHE2, respectively. Cannabinoids are the most abundant compounds in both extracts investigated, although a statistical significant difference in the relative abundance (54.23% and 70.81%, respectively) was highlighted. This difference is mainly attributable to the loss of sesquiterpenes (11.43% vs 0.17%, respectively), sesquiterpene oxides (4.82% vs 0.16%, respectively) and alkanes (15.76% vs 4.12%, respectively) during the hydrodistillation process. Both extracts showed remarkable antioxidant activity, with the following order of potency: ORAC (EC50 4.94 µg/ml) > TEAC (EC50 7.60 µg/ml) > β-carotene bleaching (EC50 21.22 µg/ml) for CHE1 while TEAC (EC50 7.78 µg/ml) > β-carotene bleaching (EC50 9.94 µg/ml) > ORAC (EC50 18.66 µg/ml) for CHE2. Total phenols content was 10820 mg GAE/100 g FW for CHE1 and 11930 mg GAE/100 g FW for CHE2. An interesting bacteriostatic and bactericidal activity against Staphylococcus aureus ATCC strain for both extracts under study was highlighted (MIC 9.77 μg/ml and MBC 39.06 μg/ml). Moreover, both extracts showed bacteriostatic activity against nine Staphylococcus aureus clinical strains (MIC 19.53-39.06 μg/ml and 9.77-39.06 μg/ml for CHE1 and CHE2, respectively), with bactericidal activity only against three of the latter ones. Therefore, results suggest that most likely the remarkable antioxidant and antimicrobial properties highlighted by extracts are mainly due to the synergy of phytocannabinoids and terpenoids.