Phytocannabinoids: The Cannabinoids Plants Build

A label, read at half past eight

Half past eight in the evening. A pipette bottle sits on the kitchen counter, turned round so the back of the label faces up. CBD first. Then CBG, CBC, CBN. And somewhere in the small print, a longer word: phytocannabinoid. Four syllables that look like they should mean something dramatic. They mean an address.

Phyto is a statement of origin

The family gets sorted by provenance, not by personality. Phytocannabinoids are the ones plants make: CBD, THC, CBG, CBC, CBN, THCV. That is the entire content of the prefix. It records where the molecule was assembled. It says nothing about strength, nothing about which name deserves the front of a bottle. A 2005 review catalogued the chemical constituents of the plant in detail, and what it records is a mixture broader than the two compounds most people can name [1].

The other two addresses

Two more groups sit alongside the plant one. Endocannabinoids are made by the body, and the examples usually given are anandamide and 2-AG. Synthetic cannabinoids come from laboratories: research compounds and pharmaceutical analogues. One family name, three return addresses. So a page that says phytocannabinoid has answered exactly one question, and it was a question about where the molecule came from.

One acid, and a fork in the path

A hemp enzyme adds a prenyl group

In 1998, Fellermeier and Zenk described a hemp transferase at work [2]. A transferase is an enzyme whose job is moving a chemical group from one molecule to another. Here the group being moved is a prenyl group, a small carbon unit, and the molecule receiving it is olivetolate. The product of that step is cannabigerolic acid, which the same paper names as the precursor of tetrahydrocannabinol [2]. One enzyme, one transfer, one new compound.

Branch point, in one word

That 1998 work also gives cannabigerolic acid, often shortened to CBGa, its position in the family: the branch point of the whole set [2]. It is worth sitting with the word branch. The names on a label look unrelated to each other, four abbreviations in a row, each with its own paragraph on the internet. Upstream of them is a shared point of departure described in the literature. So the list on the back of a bottle is not a collection of unconnected finds. It is a set of plant chemistry with a documented fork behind it, and cannabigerolic acid is where the fork sits [2].

1992: a name borrowed from the body

Isolated from brain tissue

Devane and colleagues published in 1992 on a constituent isolated from brain tissue that binds the cannabinoid receptor, and they gave it a name: anandamide [3]. Read the order of events in that sentence. The receptor already carried the word cannabinoid when the body's own molecule turned up at it. The plant compounds were described first, the receptor took its name from them, and then a molecule made inside the body arrived at the same site [3].

Receptors plus internal messengers

What that receptor belongs to is now described as the endocannabinoid system: receptors together with internal messengers, of which the two best studied are anandamide and 2-AG [3]. That is why the vocabulary looks confusing on first contact. A system inside the body carries a plant's name, and a plant compound carries the name of a system it does not live in. Neither is a marketing choice. It is the sequence in which the research happened, preserved in the words.

Six plant names, one column

1. CBD. The compound that gave the category a word people could look up. Provenance puts it in the plant column, and the 2005 catalogue of chemical constituents records it inside a mixture wider than the two best-known names [1].
2. THC. The 1998 study on hemp enzymes names tetrahydrocannabinol as the compound sitting downstream of cannabigerolic acid, which the same paper calls its precursor [2]. Plant-made, so plant column.
3. CBG. Cannabigerol shares its stem with cannabigerolic acid, the acid identified in 1998 as the product of prenylating olivetolate, and named there as the family's branch point [2].
4. CBC. Cannabichromene, another entry on the plant side, and one of the constituents the 2005 review set out in detail instead of folding into a single total [1].
5. CBN. Cannabinol is classed as a phytocannabinoid on provenance alone. The detail behind the three letters sits in the 2005 catalogue of plant constituents rather than in the abbreviation itself [1].
6. THCV. Tetrahydrocannabivarin, the sixth name here. Six is not a ceiling: the 2005 review describes a mixture broader than the pair of compounds most readers arrive already knowing [1].

Peppery, plant-made, and still a terpene

1. Beta-caryophyllene is a terpene, one of the aroma molecules of a plant, and it is not counted among the cannabinoids.
2. Its familiar sources are kitchen ones: black pepper, cloves, hops. Nothing exotic, nothing that needs a specialist supplier.
3. The receptor named in connection with it is CB2, one of the sites belonging to the system Devane and colleagues were working on in 1992 [3].
4. Which is where the sorting logic earns its keep. The three groups are defined by where a molecule was assembled, not by which receptor it happens to fit.
5. So a peppery spice can share an address with the endocannabinoid system without joining the cannabinoid family. Phytocannabinoid stays a chemistry word about origin, and CBD, THC, CBG, CBC, CBN and THCV stay the plant-side list.
6. And the honest limit: a binding site described in laboratory work and an evening with black pepper on your plate are two different registers. Only the first one is what the citations on this page cover.

From the word to the batch report

Cibdol has been formulating and testing cannabinoids since 2014, back when the word on the label needed a paragraph of explanation more than it needed a font. That has left one working habit. For each CBD product, the cannabinoid content is published together with the analysis, so the figures are readable before the bottle is opened rather than after. The prefix tells you a molecule was plant-made. The analysis tells you which ones are in this bottle, and how much. Those are two separate pieces of information, and only one of them can be printed once and left alone.

• Provenance: phyto means the plant assembled it. It carries no quantity and no ranking.
• Named entries: CBD, CBG, CBC and CBN read as separate lines, not as one shared figure.
• Shared origin: cannabigerolic acid appears in the 1998 literature as the branch point behind those names [2].
• Not an ingredient: anandamide and 2-AG are made by the body, which is why they belong to the other column [3].
• Since 2014: cannabinoid content published per CBD product, with the analysis next to it.