Cannabinoids and Terpenes: How Production of Photo-Protectants Can Be Manipulated to Enhance Cannabis sativa L. Phytochemistry

Summary & key facts

This paper reviews research on how light can change the chemicals that cannabis plants make, like THC, CBD, CBG, terpenes, and flavonoids. It explains that ultraviolet (UV) light can sometimes boost cannabinoid production in the plant’s tiny resin glands, and that some visible LED light setups can raise THC and certain terpenes but not CBD. The authors say using different light colors at different growth stages, or lighting lower in the plant, could save energy and help make more of the wanted compounds. They also warn that the evidence is still limited and that more careful experiments are needed before growers can rely on these tricks.

Key facts:

• Cannabis plants produce ‘secondary metabolites’ — chemicals like cannabinoids and terpenes that are not needed for basic growth but affect humans and have pharmaceutical interest.
• The review found that ultraviolet (UV) light can stimulate cannabinoid production in the plant’s tiny resin glands, called trichomes.
• Visible LED light has been shown in some studies to increase THC and some terpenes, but those same LED setups did not increase CBD.
• Changing the light color at different growth stages and using subcanopy lighting (light placed lower in the plant) might reduce energy use and help produce more target chemicals.
• Most studies so far focus on blue and red light; the authors say experiments with other wavelengths are needed to understand how light controls cannabinoid pathways.
• The paper notes that cannabinoids have documented health benefits and growing pharmaceutical potential, but it also says many questions remain about how best to change plant chemistry with light.

Abstract

Cannabis sativa L. is cultivated for its secondary metabolites, of which the cannabinoids have documented health benefits and growing pharmaceutical potential. Recent legal cannabis production in North America and Europe has been accompanied by an increase in reported findings for optimization of naturally occurring and synthetic cannabinoid production. Of the many environmental cues that can be manipulated during plant growth in controlled environments, cannabis cultivation with different lighting spectra indicates differential production and accumulation of medically important cannabinoids, including Δ 9 -tetrahydrocannabinol (Δ 9 -THC), cannabidiol (CBD), and cannabigerol (CBG), as well as terpenes and flavonoids. Ultraviolet (UV) radiation shows potential in stimulating cannabinoid biosynthesis in cannabis trichomes and pre-harvest or post-harvest UV treatment merits further exploration to determine if plant secondary metabolite accumulation could be enhanced in this manner. Visible LED light can augment THC and terpene accumulation, but not CBD. Well-designed experiments with light wavelengths other than blue and red light will provide more insight into light-dependent regulatory and molecular pathways in cannabis. Lighting strategies such as subcanopy lighting and varied light spectra at different developmental stages can lower energy consumption and optimize cannabis PSM production. Although evidence demonstrates that secondary metabolites in cannabis may be modulated by the light spectrum like other plant species, several questions remain for cannabinoid production pathways in this fast-paced and growing industry. In summarizing recent research progress on light spectra and secondary metabolites in cannabis, along with pertinent light responses in model plant species, future research directions are presented.

Topics

Cannabis and Cannabinoid Research GABA and Rice Research Plant Parasitism and Resistance

Categories

Health Sciences Medicine Pharmacology

Tags

Biochemistry Biology Biotechnology Botany Cannabidiol Cannabinoid Cannabis Cannabis sativa Chemistry Gene Psychiatry Psychology Receptor Secondary metabolite Terpene

Substances

Cannabis