Plants Produce Essential Oils
Mother Nature. She does the difficult work. Humans – we do the farming, gathering, and distilling.
This micrograph shows the very small cells that produce and store essential oils. They are called Trichomes (pronounced TRI-combs).
Simply touching a Trichome cell will release the essential oils. When you touch an aromatic plant (like lavender, spearmint, peppermint, oregano, thyme, rosemary, etc) some of the essential oil is released from the Trichomes. You can smell the oil on your hands. You can smell it in the air.
Trichomes generally grow on the surface of the plant stem and leaf. Plants use essential oils for survival. Their goal is to produce seed and get their seeds dispersed in the environment. Essential oils help plants survive so they can disperse their seeds.
Source: Cole Woolley, PhD on Facebook, Nov 11, 2016
Plant Primary Metabolism
How do Plants do it? How do they GROW? What do they “EAT”? What’s the source of ESSENTIAL oils?
Plants take in:
- water & minerals from soil
- carbon dioxide from air
- sunlight from the sun
- Oxygen to the air (fortunate for us Oxygen breathers)
- Carbohydrate sugars from Carbon dioxide + water
Plants grow fast in the Summer because of warmth from the Sun and capture sunlight from the Sun. They convert sunlight into chemical energy.
They use this energy to POWER their natural biochemical production – converting Carbon dioxide (CO2) and Water (H2O) into simple sugars (composed from Carbon (C), Oxygen (O), and Hydrogen (H) atoms. Plants assemble these sugars into complex carbohydrates to generate stems, roots, leaves, stock, flowers, and seeds.
Therefore, the Carbon atoms from the invisible Carbon dioxide in the air becomes VISIBLE growing plant material. WOW!
Source: Cole Woolley, PhD on Facebook, Nov 12, 2016
Plant Secondary Pathway
Recall that plants produce carbohydrate sugars (containing Carbon, Hydrogen, and Oxygen atoms) from Carbon diOxide (CO2) in the air and water (H2O) from the soil.
Plants produce essential oils by converting carbohydrate sugars into 5-carbon building blocks for essential oil chemistry. Plants use sugars, enzymes and chemical energy to produce these building blocks.
The most common 5-carbon building block is called ISOPRENE (EYE-so-preen). You won’t find the Isoprene molecule in essential oils. It is merely a building block for the chemistry.
How do plants know HOW to build essential oil molecules? Good question! Their intelligence. They have DNA intelligence that acts as a LAW and PATTERN for how to govern the chemistry within the plant.
Our DNA does the same for us in governing our unconscious biochemistry. The human brain adds to our DNA intelligence by allowing us to THINK and CHOOSE.
You’ve played “building blocks” with your kids. The chemistry of essential oil is simple – just a game of Building Blocks.
Source: Cole Woolley, PhD on Facebook, Nov 14, 2016
Isoprene Building Blocks
I hope you remember how to multiply by 5s. Like 2 x 5 = 10, 3 x 5 = 15, 4 x 5 = 20, and 6 x 5 = 30. If you do, then this exploration into the chemistry of essential oils is going to be EASY!!!!!!
Monoterpenes is 2 x 5 = 10. The Monoterpenes contain 10 Carbon atoms and a number of Hydrogen atoms. Some scientists call them “hydrocarbons”, meaning “hydrogen-carbons”. Monoterpenes dominate the percentage of molecules in essential oils
Oxygenated Monoterpenes is 2 x 5 = 10. (Well, plus an Oxygen atom). The Oxygen atoms forms Monoterpene Aldehydes, Alcohols, Ketones, and Esters. Oxygenated Monoterpenes are the “floral” and “sweet” smelling molecules in essential oils.
Sesquiterpenes is 3 x 5 = 15. Sesquiterpenes are also classified as “hydrocarbons” being composed solely from 15 Carbon atoms and a number of Hydrogen atoms. Sesquiterpenes ave rich “woody” and “earthy” aromas. Sesquiterpenes stick around based on their LARGE size. Sesquiterpenes are the biologically active molecules in essential oils.
Diterpenes is 4 x 5 = 20. These are large molecules containing 20 Carbon atoms and numerous Hydrogen atoms. Diterpenes are often ignored in essential oils because the GC-MS analysis usually does not heat up the sample above 260 degrees Celsius. However, when I run the GC-MS to 320-340 degrees Celsius, I find a variety of Diterpene molecules. Diterpenes are even more biologically active than Sesquiterpenes.
Triterpenes is 6 x 5 = 30. These huge molecules contain 30 Carbon atoms. Triterpenes have been found in essential oils by HPLC analysis. Triterpenes can be separated by GCMS by using a short capillary column with a thin stationary phase and high temperatures.
Source: Cole Woolley, PhD on Facebook, Nov 15, 2016
Essential Oil Production
With a Microscope we can see the plant cells that produce and store the essential oils you love. These cells are called Trichomes.
Trichomes come in TWO unique forms – hairlike Trichomes and globular Trichomes. Trichomes are located on the surface of plant stems and leaves.
HAIRLIKE Trichomes look like thin hairs. At the top they are crowned with 3 diverging hairs. The essential oil contained in these fine Trichomes are easily released when you touch the surface of the stem or leaf.
GLOBULAR (Glandular) Trichomes are round and robust. This is where plants produce and store MOST of their essential oil. Globular Trichomes start out like DEFLATED beachballs, then as the plant grows the ball-like trichomes fill with essential oils.
Source: Cole Woolley, PhD on Facebook, Nov 16, 2016
Steam Distilling Essential Oils
Just touching the Trichomes releases some essential oil on your hands.
When aromatic plants achieve a peak of growth and essential oil production, they are harvested.
Harvested plant material is typically dried “in the field” or “at the distillery” for 1-3 days. The drying process reduces the moisture in the plant. Drying also prepares the Trichomes to release the essential oils.
Dried plant material is placed in the steam distiller kettle. It is common practice for the distillation operators to compress and compact the plant material (by stamping) to allow steam to evenly seep through each steam and leaf.
The heated steam opens the HAIRLIKE and GLOBULAR (glandular) Trichomes to release the essential oils. The steam distillation process takes about 3 hours for each batch.
When the steam distilled plant material is extracted from the kettle it contains only a trace of the original essential oil aroma. The Trichomes are now deflated and empty.
Source: Cole Woolley, PhD on Facebook, Nov 17, 2016
Plants Use Essential Oils to Claim Domain
Plants are like Kings, Queens, Pharaohs, and Monarchs. Plants live to control their DOMAIN – space and resources. Plants use Essential Oils to control their DOMAIN.
SPACE. (I’m not talking about the final frontier from Star Trek) Plants need ground space. On the ground surface and below the surface. This is space for roots to grow. Space in the air for grow.
GROUND SPACE. Roots secure the plant/tree to the soil. Roots bring in needed water and minerals for growth. Roots work with soil bacteria for required minerals.
AIR SPACE. This domain provides new growth for plants and trees. Plants expand their greenery in the air to capture sunlight. Sunlight is converted into chemical energy. The air domain is where Carbon Dioxide is captured by the “stomata” openings in the plant. Carbon dioxide and water are used to produce carbohydrate sugars for growth and Essential Oils for protection.
Plants are constantly competing with other plants/trees for Ground Space and Air Space. They use essential oils to establish and maintain their DOMAIN.
ESSENTIAL OILS. Plants use Essential Oils to protect their Ground Space. Protection starts when mature leaves/needles of Pine, Spruce, Thuja, Tsuga, Fir, and Hemlock trees eventually fall to the ground below. The Essential Oils in the layer of fallen needles for a protective layer. The Essential Oils INHIBIT seed germination.
Consider your Experience. Do you see plants or trees growing under these coniferous trees where the layer of needles protects the ground? LOOK around today. Can you find an example of DOMAIN Control?
By controlling the Ground Space, plants and trees control the Air Space. This is the First Use of Essential Oils – DOMAIN control.
Source: Cole Woolley, PhD on Facebook, Nov 18, 2016
Attracting Insects, Birds, and Animals
One of the major purpose for plants and trees is to disperse seeds into the neighboring environment with the goal of producing offspring. Multiplying themselves.
Essential oils play a key role in attracting insects, birds, and animals to ripening fruit that contains seeds. Insects are usually the first to be attracted to ripening oranges, lemons, grapefruits, and other citrus fruits by the abundance of the LIMONENE molecule. Laying eggs in the ripening fruit provides food for their wormy young.
Birds and animals eventually consume the CITRUS fruit (and SEEDS) to complete the process of seed dispersal.
Birds and animals forage seeds from aromatic plants as they search for protein. The aromatic molecules of essential oils attract these foragers from plant-to-plant.
Essential oils help plants disperse the seeds they produce.
Source: Cole Woolley, PhD on Facebook, Nov 21, 2016
Creating a Cloud of Communication
Plants use essential oils for communication. How do they communicate without words and body language?
Plants communicate via biochemical signals. The plant releases essential oils from Hairlike Trichomes and Glandular Trichomes. The receiver (insect, animal, humans, and plants) detects the essential oil molecules using antennae, olfactory nerve receptors, and biochemical concentration.
Hairlike Trichomes send out the FIRST CLOUD of biochemical essential oil communication. These human hairlike secretory cells release a tiny cloud of essential oil whenever it is “touched”, “twisted”, or “bent”.
The thick, round Glandular Trichomes send out the SECOND CLOUD of essential oil “aroma words”. These large sacs become engorged with essential oil as the plant matures. It takes “munching”, crunching”, and “chewing” actions (usually by foraging insects and animals) to release these LARGE reservoirs of essential oils. The resulting CLOUD is LOUD.
This grasshopper will release the FIRST CLOUD by merely crawling on the Trichome-populated leaf. This may be a MESSAGE of warning: “don’t even try to eat me!!!” When the grasshopper starts munching on the leaf he will release the bulbous SECOND CLOUD of biochemical words that may send a SCREAMING message: “I warned you, now pay the consequences.”
The grasshopper detects these “CLOUDS” by its antennae. What if the grasshopper has a stuffy nose, can he detect the essential oil aromas???
Source: Cole Woolley, PhD on Facebook, Nov 22, 2016
When an insect “Chomps” on the leaf of an aromatic plant is releases a CLOUD of essential oil from the Trichome cells. The cloud of essential oil molecules spreads and dissipates in the air.
In this slide I’m showing you that PLANTS TALK and LISTEN. They speak using essential oil molecules. They listen by sensing the concentration of essential oil in the air.
GRASSHOPPER starts to eat leaf – releases essential oil. When the NEIGHBORING plant detects a difference in the essential oil concentration in the air it hears “Be on Alert, there is a hungry, CHOMPING insect near”.
In response, the NEIGHBORING plant releases essential oils as a preemptive action. It’s simply sending out a biochemical message to any nearby herbivores (insects or animals): “DON’T come near me. I’ve got MORE essential oil that I’ll release. STAY away!!!!”
Plants communicate with neighboring same-species plants and different plant species. Essential oils are the communication molecules of plants.
Source: Cole Woolley, PhD on Facebook, Nov 23, 2016
Tree Resins Seal Wounds & Defend
You may have experienced teardrop pieces of sticky gum resin or dried resin on evergreen trees: Pine, Douglas fir, Blue Spruce, Black Spruce, Alpine Fir, Ponderosa Pine, Blue Cypress, Austrian Pine, Pinion Pine, etc. Ever chew this gum? I did many times as a child and teenager.
Some of these conifer trees produce and store some essential oil-rich, sticky gum-resin in “bark-bubbles” as shown in the first photograph. This is the “first line of defense” against insects and animals. Try breaking one of these ‘bark-blisters” with your thumb – out oozes fresh, aromatic, liquid gum resin.
When a branch, limb, or the trunk of these evergreen trees snap off from heavy winds or animal movements (bears scratching their backs on tree trunks or deer/elk rubbing their antler velvet) the tree responds by releasing large quantities of essential oil-based resin to seal and heal the wound.
When a bolt of lightning strips a long scar on these tall conifer trees from the top limb down to the ground, the tree responds by releasing the liquid-flowing resin to seal the long scar.
Elemi trees growing in Philippines also release gum-resin to seal and heal wounds. From China, Australia, Japan, Taiwan, Nepal, Spain, Italy, Germany, Norway, Russia, Africa, Brazil, Canada, and Central America there are examples of gum-resin producing trees.
Source: Cole Woolley, PhD on Facebook, Nov 24, 2016
Consider Your Experiences
We’ve EXPERIENCED essential oils early in our lives. Your friends and potential clients also EXPERIENCED essential oil while they were young. THIS IS WHERE YOU START when you teach about essential oils.
Flowers. We all smelled our first flower when we were 2 or 3 years old. Probably our first essential oil EXPERIENCE.
Citrus Fruit. Zesting lemons or limes is an EXPERIENCE we can all say we saw and smelled. Later on we all peeled an orange, tangerine, or mandarin to eat the juicy citrus fruit. In the peeling process we EXPERIENCED the citrus essential oil release.
Herbs. Most of us EXPERIENCED herbs in our garden or someone else’s garden. Rosemary, Peppermint, Spearmint, Thyme, Oregano, Cilantro, and Onion are commonly grown. Just touching these plants is the EXPERIENCE.
Spices. Our moms and grandmas cooked with spices. We all EXPERIENCED the essential oil aromas of cooking. Spices like Cinnamon bark, Clove, Black Pepper, Garlic, and Cumin all possess strong essential oil aromas.
Drinks. At one time in our lives we drank a Coke, Pepsi, 7UP, Sprite, Orange Crush, Ginger Ale, or similar soda pop. They may not be healthy, but we EXPERIENCED them. These soda pop drinks consume about 85% of the “cold-pressed” citrus essential oils: Lemon, Lime, Orange, Tangerine, Grapefruit, and Mandarin. It’s also common to include Cinnamon Bark and Nutmeg essential oils in soda pop drinks.
Juices. Many juice recipes add citrus essential oils back into Orange Juice, Grapefruit Juice, Citrus Juice blend, and Lemon Juice. We’ve all EXPERIENCED these juice flavors.
When you teach your friends about essential oils, start with what they have already EXPERIENCED with essential oils. Most don’t realize it, so you need to explain their EXPERIENCES.
Source: Cole Woolley, PhD on Facebook, Nov 28, 2016
Complex Mix of Molecules
There is NO lavender molecule.
There is NO frankincense molecule.
There is NO lemon molecule.
Essential oils are a complex mixtures of natural, aromatic molecules.
- Each essential oil is a natural blend of 100-300 different, unique MOLECULE.
- Each of these molecules can be described by a biochemical SPECIFIC name.
- Each of these molecules has its own unique AROMA.
- Each of these molecules has a unique STRUCTURE and biochemical formula.
- Each of these molecules are present in a PERCENTAGE common to the essential oil species.
- Each of these molecules possesses a unique biochemical BENEFIT to humans.
Can you remember these 6 POINTS? Memorize these POINTS. Put them in your own words. Practice these phrases until you feel CONFIDENT.
The graph in this photo is a GC-MS separation of lavender essential oil. The Y-axis is Abundance (%). The X-axis is Time after Injection of sample (Retention Time). Each of these vertical lines are PEAKS. Each PEAK represents 1-2 molecules in lavender essential oil. The GC-MS “chromatogram” shows the separation of about 150 molecules found in lavender essential oil. The taller and broader PEAKS represent a higher %. Many molecules in essential oils are present at levels of 1% or less, yet their AROMA CONTRIBUTION is important.
The aroma of lavender is a COMBINATION of the 150 molecules found in the essential oil. SO, when you inhale lavender essential oil you are smelling a combination of 150 different molecules.
This is the BEAUTY of essential oils.
Source: Cole Woolley, PhD on Facebook, Nov 29, 2016
Scientists make the Difference
Testing essential oils can be done by a junior high school student of only 13 years of age. Just take a sample of essential oil with a pipette, place drops of oil in a sample vial, place the sample vial in the auto-injector, program the GC-MS, and press START. It only takes 10 minutes. Simple!!!!
The Analysis of the separated molecules in the GC-MS chromatogram takes experts (like the ones shown in these photos). Scientists with university degrees in Chemistry, Pharmacy, Biology, and NeuroScience. Scientists with PhDs, Master’s degrees and Bachelor’s degrees. Scientists with 35, 45, 32, 30, 10 and 5 years of experience. Scientists trained in NAMING the organic molecules found in essential oils.
The analysis of GC-MS data (a Total Ion Chromatogram of lavender is shown) takes about 2 hours if it is a familiar essential oil or 1-3 days if the essential oil is novel.
The GC-MS prints out a list of “most-likely candidates” for each of the separated peaks. Shhhhhh! Let me tell you a secret. “The GC-MS is wrong about 50% of the time with its TOP choice of candidates!” Remember that. This is why EXPERIENCED SCIENTISTS are needed.
Good GC-MS analysis requires CONFIRMING the names of each molecule using a system of addresses – similar to street addresses. We call this address system the RETENTION INDEX library. Here’s how it works.
Each molecule in the essential oil comes out of the GC-MS instrument at a given time (retention time). We make an additional GC-MS test using Retention Index Alkane Standards (we use alkanes from C7-C30 as standards). In the photo we have two chromatograms: The essential oil chromatogram on TOP and the Retention Index Alkane Standard chromatogram at the BOTTOM.
The Alkane Standards are given the “street address” corresponding to their Carbon number. Example: the peak representing the 8-Carbon alkane C8 is given the Retention Index (RI) address of 800, while the 12-Carbon alkane C12 is given the Retention Index (RI) address of 1200. They are like STREETS on a map.
Now for the essential oil molecules. These molecules are like HOUSES on a map between the streets. Just like house addresses they are given a ADDRESS NUMBER between the two streets where the house is located. Example: my house is located 50% between 8th Street and 9th Street therefore the STREET ADDRESS NUMBER is 850.
Retention Index values are similar. An essential oil molecule that is bordered by C8 (RI=800) and C9 (RI=900) and is positioned about 58% between the two “RI standard molecules” gets a Retention Index value (RI) of 858 (as shown in the upper chromatogram).
All essential oil molecules have a unique Retention Index value (it’s actually a bit more complicated, but this is just an introduction). So after the GC-MS scientist determines the Retention Index of an essential oil molecule, it is a matter of checking the Retention Index Library for molecules with similar Retention Index values (kind of like finding a book in the library based on the CALL NUMBER).
Match the name of the molecule from the GC-MS candidate list with the name of the molecules from the Retention Index Library to be nearly 100% certain of the IDENTITY of the molecule.
Wow, that was long!!! The process takes time to learn. University classes in Organic Chemistry and Advanced Organic Chemistry come in handy. This is the process that I follow. This is the process that I used to train scientists at Young Living. This is the process I’ve used since performing research for my PhD in Analytical Chemistry.
Source: Cole Woolley, PhD on Facebook, Nov 30, 2016
You can Detect Essential Oil Molecules
Yes. You have your own GC-MS – it’s called your nose. Most of us have a good sense of smell. You can teach yourself to detect molecules within an essential oil. It’s not easy. Here’s how…
Within your nasal cavity there are aroma sensors called Olfactory Nerve Receptors. When you inhale essential oil molecules they are detected by an array of receptors that can distinguish about 2000 different aromas.
The molecules of essential oil fit into the Olfactory Receptors like a KEY into a LOCK. Once the key fits in the correct lock, a nerve impulse is sent to the brain where a LIBRARY of AROMAS is kept. The Olfactory Receptor impulse selects from the Library to rapidly indicate to your thinking brain, “Hey, I smell LIMONENE, it must be orange essential oil”.
Now imagine the complexity of essential oil molecules. There are 100-300 different molecules in each essential oil. QUESTION: how can one selectively detect just one aroma from 300 different aromas? Not easy. It takes time.
Orange oil contains 95% limonene molecule. Start there. Now see if you can detect the LIMONENE aroma in frankincense. Then train your nose to the EUCALYPTUS molecule (about 85%) in Eucalyptus globulus. Now try detecting the Eucalyptus aroma in Rosemary and Lavender essential oils.
Imagine how many Olfactory Nerve Receptors are triggered when you inhale 200 different molecules in just one essential oil.
Source: Cole Woolley, PhD on Facebook, Dec 1, 2016
Try this Experiment with your Nose
Every essential oil has aromas that can be classified as LIGHT NOTES, MEDIUM NOTES, and HEAVY NOTES. Light Notes are the first aromas detected and the first ones that leave. Heavy Notes are the last aromas you detect, but they linger on for hours. Medium Notes are have properties in between the other two notes. Try an EXPERIMENT…
Open a bottle of frankincense or lavender essential oil. Hold the open bottle at arms length. Start inhaling…
The FIRST aromas will be the LIGHT NOTES. Light Note molecules move quickly in the air. Light Notes do not linger; they keep moving to fill the room and escape out the doors. The aroma of these molecules varies, but includes “piney, fresh, orangey, eucalyptus-like, sharp, and herby”. It takes about 10 seconds to detect the LIGHT NOTE molecules.
The SECOND aromas you detect will be the MEDIUM NOTES. Medium Note molecules move less rapidly in the air than Light Note molecules. They tend to linger longer. Medium Note molecules have rich “floral, sweet, or flowery” aromas. You like Medium Note molecules! It takes about 30 seconds for you to detect the MEDIUM NOTE molecules.
The THIRD aromas you will detect are the HEAVY NOTES. In order to detect these aromas you will have to bring the bottle of essential oil close to your nose. These molecules linger in the bottle. They do not like to travel in the air. These molecules are like you when you carry 3 heavy suitcases to the car – you move slowly. These molecules give off a “woody, earthy, intense” aroma. You will have to clear out the aromas from the LIGHT and MEDIUM NOTES from your mind to detect the HEAVY NOTE molecules.
Try this at home. It’s a great EXPERIMENT.
Source: Cole Woolley, PhD on Facebook, Dec 2, 2016
Light, Medium & Heavy Notes
We all understand that aromas are sometimes “light”, meaning they come and go quickly. We also understand “heavy”, meaning the aroma lingers for a long time.
Your nose is like your own GC-MS instrument. Your experiment last week helped you to see the difference between light and heavy notes.
Light Notes… These are the molecules that are small, usually only 10 Carbon atoms. These molecules move quickly to fill a room. They also escape the room quickly. These small molecules easily permeate wood, plastic, and stone. These molecules usually have an aroma of “piney, sharp, and orangey”.
Medium Notes… These molecules also have 10 Carbon atoms, but also contain at least one added Oxygen atom. This Oxygen atom attracts the Medium Note molecules to water and moist surfaces. They tend to linger on the skin, in the lungs, in the sinuses, and in the blood. Medium Note molecules usually have an aroma of “floral, sweet and flowery”.
Heavy Notes… These molecules possess 15 Carbon atoms. Because these molecules are larger the move slowly in the air and tend to linger on surfaces. Heavy Note molecules stay on your skin, on household surfaces, and within your body longer because they are larger. The typical aroma of these molecules is “woody, earthy, intense”.
Essential oils may contain all 3 of these Notes. When a drop of essential oil is placed on the skin the Light Notes evaporate first (the first aroma you detect). Within 30-60 minutes the Medium Note molecules evaporate from the skin. Finally, you are left with the Heavy Note molecules and their aromas that may detected all day.
EXPERIMENT: Place a drop of frankincense on your skin. Monitor the aroma for 3 hours. Could you detect the Light, Medium, and Heavy Notes?
Source: Cole Woolley, PhD on Facebook, Dec 5, 2016
Lavender’s Light, Medium & Heavy Notes
Recall that every essential oil is composed of 100-300 different molecules – each with its own aroma and biochemical benefits. Let’s look at these molecules using GC-MS to separate them.
LAVENDER. Lavender essential oil is a good example of Light, Medium, and Heavy Notes. This GC-MS total ion chromatogram depicts many of the prominent molecules.
LIGHT Notes. Some Light Note molecules and aromas:
1. Alpha-pinene (trace-0.5%) – “piney, woody, herbal”
2. Trans-beta-ocimine (2-4%) – “tropical, green, herbal”
MEDIUM Notes. Some Medium Note molecules and aromas:
1. Linalool (30-40%) – “floral, citrus, sweet”
2. Terpinen-4-ol (2-4%) – “woody, menthol-like, citrus”
3. Linalyl acetate (25-33%) – “sweet, citrus, lavender”
4. Lavandulyl acetate (2-5%) – “fresh, citrus, fruity”
HEAVY Notes. Some Heavy Note molecules and aromas
1. Trans-beta-caryophyllene (2-5%) – “spicy, peppery, woody”
2. Trans-beta-farnesene (3-6%) – “woody, citrus, sweet”
Note the different aromas of just 8 molecules. Now add more than 100 and the aroma complexion is amazing!
EXPERIMENT: See if you can pick out the aromas LINALOOL and LINALYL ACETATE – they are the most abundant. Try it 3 times. You may have to smell coffee grounds between each attempt. Can you detect these 2 molecules???
Source: Cole Woolley, PhD on Facebook, Dec 7, 2016