by Ed Rosenthal
In the past few years, CBD has gotten considerable attention for its anticonvulsant properties. Concentrated CBD extracts alleviated the seizures of several children with severe seizure disorders that did not respond to other medications. GW Pharmaceuticals is now testing a CBD extract in clinical trials with children who suffer from intractable seizure conditions.
Plants that have been bred to have high concentrations of THC typically have considerably less CBD. The therapeutic qualities of CBD have also gained the attention of breeders, and more CBD-rich varieties of marijuana are becoming available.
CBG (cannabigerol) is a nonpsychoactive cannabinoid with at least 16 subtypes that is the direct precursor to delta-9 THC, CBD, and CBC. There is rarely much CBG present in mature marijuana, although some varieties have percentages as high as 4%. CBG is an antimicrobial, as are other cannabinoids, and has several other biological effects with therapeutic potential. It is a more powerful pain-killer than THC and may be effective for psoriasis and depression.
CBC (cannabichromine), which results from decarboxylating cannabichromenic acid (CBCA), is inactive in its pure form, but is suspected of potentiating THC. Some tests made for CBD may actually measure CBC, which is chemically similar. CBC is abundant in immature plants and has at least eight subtypes. As with other cannabinoids, varieties have been selectively bred that have substantial concentrations of CBC, and significant amounts have been found in some potent varieties.
CBE (cannabielsoin) is a derivative of CBD that may be found in hash as the result of oxidation or heat. It is also a metabolite of CBD that can be detected in humans.
CBT (cannabitriol) has been found in male flowers, some Asian varieties of cannabis, and occasionally in hash.
CBN (cannabinol) is produced by the degradation of THC after harvest. It is only slightly psychoactive, at best about 10% of THC’s effect. Fresh samples of marijuana contain very little CBN, but curing, poor storage, or processing can cause the THC content to be oxidized into CBN. When marijuana is pressed for shipping, the resin glands that hold and protect THC are sometimes ruptured, exposing the cannabinoids to air and increasing the rate of oxidation.
CBN seems to exaggerate THC’s disorienting qualities, making you feel more drugged, dizzy, or generally untogether, but not necessarily higher. With a significant proportion of CBN, the high may start well and then feel as if it never reaches its peak, and may not last long.
How to Read the Following Charts
Reading horizontally: The physical state of cannabis is raw, heated, aged. Raw refers to the fresh plant. Aged refers to the degradation effects of UV-light, oxidation, and isomerization.
Reading vertically: How do cannabinoids relate to each other? Where do they come from?
Courtesy of Elemental Wellness Medical Cannabis Dispensary
Courtesy of Elemental Wellness Medical Cannabis Dispensary
Courtesy of Elemental Wellness Medical Cannabis Dispensary
Courtesy of Elemental Wellness Medical Cannabis Dispensary
THE TERPENES
Like many other plants, cannabis contains terpenes and flavonoids. Terpenes impart the strong odors characteristic of good weed and have therapeutic properties of their own. Terpenes also interact with cannabinoids in ways that affect how the body absorbs and utilizes them.
Terpenes are essential oils that plants produce for one of three reasons: to attract pollinators, to attract predators of herbivores that attack them, and to repel and/or kill predators and pathogens. Each terpene has a characteristic odor easily recognizable for its association with other plants. The recipe of terpenes and their concentration varies by variety. The combination gives marijuana strains identifiable odors: sour, diesel, fruity, pine, etc. The amount of any given terpene in the marijuana you smoke or ingest is relatively small—usually no more than a fraction of a percent.
Since the bioavailability of terpenes is in the range of 18%, roughly similar to THC and other cannabinoids, only tiny amounts of terpenes make it into the bloodstream. Still they have a tremendous medical and psychoactive effect.
Terpenes are used in aromatherapy to alter mood, attitude, and outlook, as well as for physical effects. When used in conjunction with cannabis they influence the high. Most experienced marijuana consumers understand this informally. If you were to be handed a bud, your first action would probably be to look at it. The second thing you would do is smell it. THC, CBD, and the other cannabinoids have no odor. What you would be smelling are the terpenes. You know from experience that the odor of the bud is an indication of the kind of high it produces. That’s why two different varieties that have the same THC content can have different effects—it’s the terpenes.
The same terpenes found in marijuana appear in different types of plants. For instance, a bud with a citrus odor such as lemon or grapefruit most likely has limonene, which is associated with those fruits. Other fruit and flower odors are often produced from other familiar terpenes, such as pinene, which has a pine-like odor, and myrcene, which has a faint nutty odor, to name just a few of many. You could say THC is the engine that drives the high, and the terpenes are the steering wheel. Is it taking you up? Is it focusing, relaxing, or making you tired or energetic? It’s the terpenes.
It takes only a few parts per million (ppm) of most terpenes for you to smell and identify the scent. Even at these low levels they have a profound effect on us psychically, psychologically, physiologically, and medically. Many of the effects of terpenes derive from the activation of the olfactory bulb, the part of your brain that processes odor. The nose odor receptors are sensors with their own direct connection to the brain and are used to process information about the environment. This is why aromas have such a powerful effect. That smile your friends get when you stick some fine bud under their noses and let them take a big sniff isn’t just anticipation of the experience that’s coming; the smell is having its own effect.
Some terpenes, such as myrcene, have an effect once they enter the bloodstream. Myrcene passes through the blood-brain barrier and increases its porosity so that more THC enters faster, causing a quick-onset high. B-caryophyllene is associated with a relaxed feeling and sociability. Other terpenes have other special effects. Terpenes may have more effect on the high and some medical conditions than CBD or cannabinoids other than THC.
To fully experience the power of terpenes, use a vaporizer. The essence you smell and taste is mostly terpenes and flavonoids. Heavy smoke from combusting plant material can be satisfying, but the tars and smoke mask the delicate odors. Terpenes have a range of temperatures at which they begin to evaporate, just like cannabinoids. Some are volatile at 70°F (21°C). Most of them evaporate at below 150°F (66°C). So vaporizing releases the cannabinoids and virtually all of the terpenes and flavonoids.
As cannabis consumers become connoisseurs and changing laws make more choices available, terpene profiles will gain importance. When confronted by a dozen or more strains at a dispensary, all of which are of superior quality and pack substantial percentages of THC and possibly CBD, the terpene profiles of particular strains will make them more popular than others. Actually, that already happens. Odors signal the quality of the bud. The delineation of terpenes that is happening now will help consumers choose the variety that is right for them.
The cannabinoids and terpenes are produced in the trichomes that are most abundant around the maturing female flowers. The oil the glands hold has a mixture of cannabinoids and terpenes.
Two of the most important terpenes in terms of their effects are β-myrcene and Linalool.
β-myrcene is the most abundant terpene in most varieties. It has anti-inflammatory, analgesic, antibiotic, and antimutagenic properties. It is found in Cavicol and other varieties of mangoes.
Linalool is also found in lavender, roses, and some citrus. It is typically only about 5% of the essential oils in marijuana, but it has important biological effects. Linalool is the most powerful sedative of all the terpenes. It is antidepressan
t and helps reduce anxiety.
α-terpinol is a sedative and acts synergistically with linalool to enhance the effect. It is antidepressant and helps reduce anxiety.
d-limonene is found in abundance in citrus. It is focusing, stimulating, antidepressant, and helps reduce anxiety.
a-terpineol has antibiotic, antioxidant, and antimalarial properties. It has a vaporizing temperature of more than 426°F (219°C), notably higher than some cannabinoids and other terpenes.
β-caryophyllene lightens people’s moods and helps them socialize. It has anti-inflammatory, antimalarial, and cytoprotective properties. It vaporizes at 246°F (119°C).
Pulegone has sedative and other properties.
1,8-cineole (eucalyptol) has stimulant, antibiotic, antiviral, and anti-inflammatory properties.
a-pinene has a pine-like odor and has anti-inflammatory, antibiotic, stimulant, and other properties.
p-cymene is an antibiotic.
Appendix 2.
Equivalents and Conversions
Measurement Abbreviations
t
=
teaspoon
g
=
gram
T
=
tablespoon
kg
=
kilogram
c
=
cup
mL
=
milliliter
pt
=
pint
L
=
liter
qt
=
quart
oz
=
ounce
lb
=
pound
Fluid Equivalents
3 t
=
1 T
=
14.68 mL
4 T
=
¼ C
=
59.1 mL
1 c
=
8 oz
=
236 mL
2 c
=
1 pt
=
473 mL
2 pt
=
1 qt
=
0.94 L
Dry Equivalents
¼ oz
=
7.1 g
½ oz
=
14.2 g
1 oz
=
28.4 g
8 oz
=
227 g
16 oz
=
454 g
=
1 lb
1000 g
=
1 kg
=
2.2 lb
100 kg
=
a federal rap
U.S. Food Measures
Butter:
1 lb
=
2 c
Flour:
1 lb
=
4 c
Sugar:
1 lb
=
2 c
Temperature Conversions
Fahrenheit
Celsius
150
66
212
100
250
121
275
135
300
149
325
163
350
177
375
191
400
204
425
218
450
232
475
246
500
260
550
288
600
316
Powdered Marijuana Leaf and Bud
1 t
=
1.8 g
1 T
=
5.5 g
=
-¼ oz
¼ C
=
22.4 g
⅓ C
=
28 g
=
1 oz
½ C
=
45 g
⅔ C
=
56 g
=
2 oz
1 C
=
84 g
=
3 oz
Screen Sizes
100 microns
=
0.1 millimeter = 0.0039 inches
75–125 micron screen
=
approximately 100–150 strands per inch screen
Typical marijuana gland size range: 75–125 microns
Appendix 3.
Glossary
710: the cannabis oil community’s version of “420”; “oil” upside down
absolute: the dewaxed essence of a botanical extraction
boiling point: the temperature at which a substance turns to gas; cannabinoids and terpenes have different temperatures at which the oils vaporize and escape into the air
botanical extraction: the process of removing a plant’s essential oils, resins, or other components through any number of means (mechanical, steam, solvent, etc.)
butane: simple, explosive hydrocarbon used in botanical extractions
BHO: abbreviation for “butane hash oil”; can refer to any number of concentrates derived from butane extraction; also can refer to raw, unpurged, liquid solution of butane and extract
bubble hash: cannabis glands concentrated by means of ice water
budder: a type of BHO that is opaque and malleable
buddering: when translucent BHO clouds over
bulbous trichome: the smallest of the marijuana plant’s cannabinoid-rich glands, measuring from 15 to 30 micrometers; the “foot” and “stalk” are one to four cells, as is the “head” of the gland
cannabidiol: second most common cannabinoid found in cannabis, with many confirmed therapeutic benefits
cannabinoid: a class of molecules produced by cannabis; there are more than 100 of them. Many interact with the human nervous system to produce the wide variety of cannabis’s effects.
capitate-sessile trichome: cannabinoid-rich marijuana glands, measuring from 25 to 100 micrometers, that stay close to the plant surface on stalks a cell or two high
capitate-stalked trichome: the largest and most abundant of the cannabinoid-rich marijuana glands, measuring from 150 to 500 micrometers; contains the bulk of the cannabinoids and terpenes
concrete: a botanical extraction that includes the plant’s essential oils, as well as its waxes and lipids
conduction: heat transfer through solid matter, such as metal; a conduction vaporizer has a metal or other hot element as its heat source
convection: the transfer of heat by automatic circulation of a fluid; a convection vaporizer circulates hot air or fluid to produce the proper temperature
critical phase: a fourth phase of matter; a combination of intense pressure and/or temperature. Critical CO2 has a different solubility than liquid or gas.
critical point: the combination of temperature and pressure beyond which a substance is in its critical range. Supercritical substances have different solubility than their other phases, opening the door for extraction.
dab: a small amount of concentrated marijuana extract (i.e., BHO), equivalent in size to a grain of white rice
dab rig (oil rig): a water filtration pipe designed for vaporizing concentrates
decarboxylation: the removal of a carboxyl, which is a carbonate molecule (COOH). When carboxyl molecules are attached to the THC molecule, it is called THCA, or THC acid. In this form, THC lacks most of its psychoactivity. Decarboxylation removes the COOH acid molecule, leaving behind THC. Mild heat is often used to convert THCA to THC. This happens during drying, vaporization, and smoking. Some decarboxylation happens naturally as marijuana cures and age
s.
diffusivity: the ability of a substance to dissolve into another substance, a factor in CO2 extraction
dry sift: another term for kief
endocannabinoid: the natural cannabinoids produced in the body by humans and other vertebrate animals that regulate complex biological processes, including those of the immune system; endocannabinoids attach to specific receptors that also respond to phytocannabinoids
essential oil: a concentrated hydrophobic liquid containing volatile aroma compounds from plants
emulsifiers: Emulsifiers promote suspension of small, fatty globules in water. When water and oil are mixed together, they quickly separate. However, in the presence of an emulsifier the oil breaks into small bits suspended in the water. Two examples of this are milk and commercial salad dressings. Lecithin is a common emulsifier that is available in health food stores.
gland: the trichome filled with cannabinoids and other essential oils, found on external surfaces of the plant, especially the upper side of leaves surrounding the female flowers
health stone: a porous ceramic filter placed in a pipe bowl used to smoke concentrates
hydrophobic: resistant to water—for instance, the waxy covering of trichomes; chemically, substances that don’t combine with water
inflorescence: the botanical term for marijuana buds or flowers, referring to a cluster of flowers on a stem composed of a main branch or arrangement of branches
juicing: the process of reducing to a liquid the nutrients and other ingredients of fresh plant material either by pressing or blending