**3. Phytocannabinoids**

The *Cannabis sativa* L. plants produce more than 560 chemicals, including at least 144 cannabinoids and 200 terpenoids, as well as flavonoids and polyunsaturated fatty acids [15,33,34,42,63,67,72,73,90–107]. The most common phytocannabinoids are Δ9-tetrahy drocannabinol (Δ9-THC) and cannabidiol (CBD), which are the neutral homologs of tetrahydrocannabinolic acid (THCA) and cannabidiol acid (CBDA), respectively [108]. The phytocannabinoids are terpenophenolic compounds containing a resorcinyl core with a parapositioned isoprenyl, alkyl, or aralkyl side chain [39,40] (Figure 1). The tetrahydrobenzochromen ring is quite unique to the genus *Cannabis*, although a related compound has been found in the liverwort *Radula marginata* [109], and cannabigerol (CBG) and its corresponding acid have been isolated from *Helichrysum umbraculigerum* [110].

Apart from exerting anti-microbial activities, which will be discussed in more detail below (Section 3.3), phytocannabinoids modulate several physiological and pathophysiological processes in humans and other mammalians, making them potential therapeutic drugs in various settings [12–14,31,111–115]. Among others, these compounds have been shown to have anti-inflammatory, anti-oxidative, anti-nausea, anti-nociceptive, anti-convulsant, anti-neoplastic, anxiolytic, and neuroprotective properties [14,111,112,114–117]. Cannabinoids also affect cognition, such as learning and memory, consciousness, and emotion, including anxiety and depression [118,119].

Some cannabinoid-based drugs (e.g., Marinol, Syndros, Cesamet, Sativex, and Epidiolex) have been approved by the U.S. Food and Drug Administration (FDA) for the treatment of epilepsy, Dravet syndrome, Lennox–Gastaut syndrome, Parkinson's disease, spasticity associated with multiple sclerosis, neuropathic pain, mental illnesses, chemotherapy-induced nausea, and AIDS wasting syndrome [117,120–122]. Marinol and Syndros contain the (-)-trans-Δ9-THC dronabinol; Cesamet contains the synthetic cannabinoid nabilone that shows structural similarities to Δ9-THC; and Epidiolex contains CBD. Sativex is produced from a *Cannabis*-derived extract that is composed of approximately equal quantities of Δ9-THC and CBD. A major concern is the production of many psychotropic synthetic cannabinoids distributed on the illicit market, which poses a potential health treat due to their high potency and toxicity [123].

**Figure 1.** The chemical structures of some phytocannabinoids and the synthetic cannabinoid HU-210.
