Will Cannabis be the next antibiotic?
The Growing Need for Novel Antibiotics
Multidrug-resistant bacterial infections have long been a growing concern in the medical community. Infections from methicillin-resistant Staphylococcus aureus (MRSA) and newer concerns over the extremely drug-resistant Mycobacterium tuberculosis XDR-TB are extremely dangerous because they resist commonly used antibiotics and can build resistance to antibiotics reserved for treatment of resistant infections. Very few new antibiotics have been developed in the last 30 years. More new antibiotics are needed to continue the fight against multidrug-resistant bacterial infections.
Cannabinoids Combating Bacterial Infections
Many natural plant compounds show antibacterial properties, the plant compounds of interest in cannabis are called cannabinoids. The five most common cannabinoids are cannabidiol (CBD), Δ9-tetrahydrocannabinol (THC), cannabichromene (CBC), cannabigerol (CBG), and cannabidiol. All five have shown potent antibacterial activity against MRSA in addition to their growing reputation of having medicinal properties.
Cannabinoids like THC and CBD are the product of decarboxylation. Carboxyl groups are molecules that contain a specific arrangement of carbon and oxygen atoms. Decarboxylation removes that group from the rest of the chemical compound. This releases CO2 and changes the compound into a new version of the compound. For cannabinoids, this reaction takes place when the cannabinoids are heated and results in an active form that can act on human brain chemistry.
The antibacterial properties of cannabis are uniquely found in both the carboxylated and decarboxylated versions of cannabinoids. Testing suggests that cannabinoids work against bacteria through “lipid affinity,” similar to how antibacterial soaps work. Because cannabinoids fight bacteria in a way that is different from the way most current antibiotics work, they are an attractive option to consider in developing new antibiotics that can combat highly resistant bacterial strains. Cannabinoid extracts have also shown antioxidant activity.
Bacteria Susceptible to Cannabinoids
Inhibition studies of cannabinoids extracted with water or alcohol both showed significant antibacterial action. Alcohol extracts produced a more potent extract with higher cannabinoid concentration and more potent antibacterial activity. In addition to highly pathogenic bacteria like MRSA, cannabinoids inhibited more common bacteria and fungi like Pseudomona aeruginosa, Vibrio cholerae, Staphylococcus aureus, Bacillus cereus, Klebsiella pneumoniae, and Proteus mirabilis, and fungi Cryptococcus neoformans, Candida albicans, Aspergillus niger, Aspergillus parasiticus, and Aspergillus oryzae.
From Field to Pharmacy
Highly pathogenic bacterial infections like MRSA are attributed to more deaths worldwide than AIDS. Developing new antibiotics takes a long path of development, clinical trials, and approval. It is important for researchers to start with the most promising antibacterial candidates. The body of studies from the last 10 years suggests that cannabinoids are a promising prospect.
More study is needed to consider the influences of genetic strain and extraction method on antibacterial activity. Some researchers have reported only modest antibacterial properties in cannabis extracts, but further studies have noted that strain and extraction methods can be a major factor inactivity. With the evidence for the antibacterial properties of cannabinoids growing, cannabis has real potential to become the next penicillin.
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