Abstract

Due to its limited treatment options, multi-drug resistant bacteria such as Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) still remains a serious public health threat. The creation of new compelling antimicrobial ma- terials, antibiotics and optional methodologies, which are suc- cessful against resistant microbes, is earnestly required. The le- galization of cannabis in Canada has provided a new opportunity to investigate the antimicrobial studies of both ex- tracts and individual cannabinoids.
This study investigates pure cannabidiol (CBD) isolated from Cannabis sativa by using a methodology of extraction, purifica- tion, characterization, and quantification of CBD. The shredded plant material was dissolved in ethanol, with the extract further purified using supercritical fluid chromatography (SFC) to ob- tain purified CBD. Product purity was confirmed by HPLC and NMR spectroscopy. CBD’s antibacterial activity on MRSA strain USA300 bacteria was studied using dilution series in liq- uid culture and disk diffusion assays to provide the minimum inhibitory concentration (MIC) and minimal bactericidal con- centrations (MBC). We have also performed statical analysis between CBD concentration groups with no CBD (control) and found a significant difference in cell counts of these groups. Past papers had not shown any MBC values – we have obtained a novel MBC value for CBD industrially extracted from Cana- dian grown C. Sativa plants.
The results showed that CBD exhibited a significant bacteri- cidal effect on MRSA with the MIC value of 2.5 μg/mL and MBC of 10 μg/mL. CBD powder form gave a higher antimicro- bial activity than its oil form in terms of the inhibition zone. This study shows that CBD exhibits good antimicrobial impact against the MRSA strain showing its utility for enabling a new antibiotic-free method for treating MRSA infections.