When someone initially gets interested in herbalism they often have no idea that they will eventually need to understand the basic chemistry of herbs. But most of us will need to dive into this arena. For some it may be about understanding the science of herbs and for others it can be a necessary step to making potent plant medicine.
For those people interested in the western bio-medicine approach to herbalism, understanding plant constituents gives insights into how herbs work. For example, turmeric is high in curcumin which has been studied extensively and found to have a wide range of benefits or medicinal actions. Therefore turmeric is considered to be therapeutic because of it's plant constituents. (In contrast, or complement, to traditional herbalism which tends to look at herbal actions and energetics to determine use.)
This article is focused on basic understandings of plant chemistry for the purpose of making potent plant medicines. Or why extracting poplar buds in 20% alcohol is not a great idea or why extracting marshmallow root with 95% alcohol probably won't work out well.
The following is a very basic list of constituents and the mediums they are soluble in to help beginning herbalists making plant medicines.
To delve into the chemistry behind plant constituents please refer to the reading list at the end of the article.
Common Chemical Compounds
Alkaloids
Soluble: alcohol, water, vinegar
Alkaloids posess a huge variety of effects ranging from benign to extremely poisonous. They are extracted extremely well by alcohol and much less so by water (Cech). Plants high in alkaloids are goldenseal, lobelia, and motherwort. Alkaloids can be sometimes dissipated with heat or tannins, or magnified with vinegar (Cech).
Glycosides
Soluble in: water, alcohol
A glycoside is chemically described as a compound that contains a sugar as part of the molecule. There are several different types of glycosides with a variety of effects including beneficial and toxic effects on the heart (cardiac glycosides found in Digitalis and Hawthorn), laxatives (anthraquinone glycosides found in senna, rhubarb), and antiseptic qualities (arbutin found in Uva ursi). Stevia, rebaudiana bertoni, another glycoside, has 40-300 times the sweetness of sucrose.
SaponinsSoluble in: water, alcohol
Saponins are a special type of glycoside. We use saponins (hopefully) daily in our soaps. Saponins break up fat molecules (think of the Dawn commercials and the big piles of dirty dishes). They also have a variety of other effects including adaptogenic, diuretic, anti-spasmodic, and expectorant (Cech). Horse chestnut, licorice, and chickweed all have saponins.
Flavonoids
Soluble in: water, alcohol
Flavonoids are another type of glycoside. Among the important effects of flavonoids is their antioxidant effect. An antioxidant is a molecule capable of slowing or preventing the oxidation of other molecules. They are also known to decrease capillary fragility.
Tannins
Soluble: glycerin, water, alcohol
Oak, tea, witch hazel, and red clover all contain tannins. Herbs with high tannin content are generally used as an antiseptic, a styptic, and to shrink tissues. Tannins are rendered inactive with the presence of milk and may have the ability to render some alkaloids inactive (Kress, Cech).
Mucilage
Soluble: Water (Cold preferred)
Soothing to the gut and urinary system, herbs high in mucilage also tend to be nutritive and nourishing to the immune system (Cech). Herbs with high mucilage content include marshmallow, mullein, comfrey, and slippery elm.
Polysaccharides
Soluble: water
Generally immune stimulating and nutritive, herbs high in polysaccharides are burdock, astragalus, and boneset (Cech).
Minerals, trace elements
Soluble: water, vinegar
Vitamins
Soluble: water,
Vitamins A, D, E, and K are fat-soluble, with the rest being water soluble.
Resins
Soluble: alcohol, oil
Resins are typically expectorant and bitter. Herbs containing high amounts of resins include cottonwood buds, calendula, and gumweed.
Solvents
Water
Water extracts almost everything with the exception of resins. Different temperatures may effect the extraction (simmering for barks and roots, just boiled for leaves, cold for mucilaginous plants). Some herbalists prefer to use distilled water.
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| Marshmallow cold water infusion |
Alcohol
Almost everything is extracted by alcohol with the exception of minerals and trace elements. The percentage of alcohol used in plant medicine can be determined by it's plant constituents. For example, resins must be extracted in 95% alcohol (cottonwood buds, propolis and myrrh are good examples). Other alcohol percentages for certain plants are based on scientific queries into constituents or personal preference. Richo Cech has a nice listing in his book, Making Plant Medicine.
Mucilage is extracted by alcohol and then broken down by it, so it's best to use a cold water infusion and then add just enough alcohol if wanting to preserve it.
Proof vs. percentage
In the above photo you can see it listed as 100 proof. The alcohol percentage is half of the proof. So in this case the above vodka is 50% alcohol.
Everclear (which is only available in certain states) is 95% alcohol - the highest percentage possible. (Note that some states carry everclear at 151 proof only, be sure to check.)
Many vodkas, brandy's and other liquors are 40% alcohol. In general it is best to choose a pure alcohol, not one that is flavored (with who knows what!).
Glycerin
Glycerin is a sweet substance made from plant or animal sources and is chemically related to alcohol. It's made by the breaking down of fat and oils with the use of high pressure steam (Cech). Herbalists use glycerin to extract medicinal properties from plants when wanting to avoid alcohol.
Glycerin does poorly at extracting properties with dried plant material so fresh plants are highly recommended. According to Henriette Kress, some minerals and trace elements, some alkaloids, some acids, and some mucilage are extractable with glycerite. Richo Cech reports that tannins are extracted very well by glycerin.
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| Glycerin being added to a willow bark tincture to further extract tannins. |
Oil
Oils have the ability to extract oils and resins.
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| Calendula flowers extracted into olive oil. |
Vinegar
Vinegar has the ability to extract minerals, trace elements, and alkaloids. Most herbalists use apple cider vinegar, balsalmic vinegar, or other high quality vinegars. (Distilled white vinegar is not reccomended for internal use.)
Besides extracting a variety of constituents, vinegar can also add other benefits to the end product as well. It is considered specific for digestion and the respiratory system.
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| Chickweed being extracted with vinegar. |
Further Reading
The best resource on herbal chemistry is Lisa Ganora's book:
The nurseries around my house do not offer this particular basil variety. I had to go to Ohio to find it. So if you are fortunate enough to live near a good nursery that carries a variety of herbs, you may be able to get 'Minette'. It is better than even 'Spicy Globe'. It keeps its shape and is very prolific! Here is the 'Minette' early on in the garden. It's the fourth plant from the left. The little round mound.
Several years ago when we opened e-mail addresses, I decided that I would not use my real name, but an herb. It was easy to pick the herb, lemon verbena (Aloysia triphylla) was it. Cedron is Spanish for lemon verbena. It was the herb of the princess (Maria Louisa, wife of King Charles IV of Spain). Don't confuse it with lemon grass. It is a plant of American origin (that is Chile). It is a perennial in tropical areas that can reach to ten feet high. It is a tender perennial for us in the north. We always have it on our kitchen windowsill in the winter. When you bring it in, it will play dead and lose its leaves. Use them for tea, in a tea bread (recipe follows) or in potpourri. You should water it every week to ten days. Then in December cut it back to about three or four inches. In February it will resprout and by the time it is ready to go outside in May, you will have a plant like the one in the photo above.
This is a favorite edible flower from Peru, the nasturtium (Tropaeolum majus) flowers and leaves are both edible. They were grown by kings such as Louis XIV of France and President Thomas Jefferson grew them also. The flowers and leaves have a peppery taste. The flowers shown in the picture below are from the 'Whirlybird' series because they do not have a spur. A little crook in the back of the flower is the spur. It can hide insects taking a nap, small ants in particular! They grow very easily in well drained soil and do not need fertilizer because that will lead to more leaves than flowers. The plants are very easily grown from seed so it would be a good one to plant with your kids. The variegated leaf is from the 'Alaska' series. Sometimes the leaves get as big as doilies and I have used them as such on an appetizer platter. One of my favorite ways to eat the flowers is filled with guacamole. Don't forget to take out the reproductive parts of the flower before eating and only eat organically grown flowers. They are a great fall flowering plant until a hard frost comes along. 
Here is one of my favorite annual flowers from Peru. They are on British time because instead of blooming at 4:00 o'clock as their name implies, they bloom at 11:00 A.M! Four o'clocks are fragrant, easy to plant from seed and are a staple in our garden. They would be a good flower for children to plant and grow. They come in white, yellow and this magentia color. They bloom from late July through frost. The seeds are big and black, drop to the ground and reseed easily if they like the spot. Annuals bridge the gap between perennials in the garden. Don't forget to plant them!
Well, the hummingbird has continued to visit the pineapple sage and butterfly bushes in our garden. She even tried to get something from the tansy! I hope you can see it in the bottom left of the picture on the butterfly bush 'Black Knight'. Click on the picture to enlarge it.
Here in the garden we have many insects and birds and also butterflies. I always look forward to seeing monarches on the butterfly bushes in the front and back gardens. It means the end of the summer because they are off to faraway Mexico. They are a great addition to the garden.
I am an herb plant collector. We have a lot of herb plants that reside in our basement and garage in the winter. This is a Peruvian salvia called Salvia discolor 'Andean Silver'. The blooms are black and the leaves are green with a white backing. It may be one that is dug up and placed in a pot for the winter. Not what my husband wants to hear! You can find this plant at Companion Plants and Well-Sweep Herb Farm. 
Our new neighbors at the market this year are Steve and Mary Prescott from Prescott's Patch. They are farming organically without the certification. To me, knowing the farmer and seeing how they feel about their produce is more important than the certification. Last week Mary told me this was Steve's mission in life - to grow these heirloom fruits and vegetables, and to do it in a sustainable way. Sometimes you can just tell about people, ya know? They have an easy way about them, and the customers just love them. Ask them about a variety, and chances are they can tell you how to cook it, what it goes well with, and maybe even a favorite recipe.
Their display is colorful and inviting, and every week I wind up trying something. Last year Kharren did that with her incredible variety of veggies, and I miss her. It's good to have someone here challenging my taste buds again. See those variegated eggplants? They actually taste a little creamier than the all-purple ones. Really! Every time a customer takes a bunch of basil, my sister and I sigh as the aroma reaches our booth, and the red raspberries seem to be every one's favorite. In case you read this, Mary, go ahead and try that new variety of sweet potato! It isn't too sweet. You might like it.
Then we have Bill and Lil from Grandma's Goodies. Most mornings we have to start off with a Rice Krispie Treat, and lately she's been bringing coffee. Those pumpkin whoopie pies are KILLER! Not too sweet, perfectly spiced (yes as a matter of fact, I AM a pumpkin bread aficionado)... oh, they're good all right. They make some mean pies (I'm partial to Shoo-fly), and today I brought home a carrot cake for the girls to eat when they get home from working at the renaissance faire tonight.
Of course we always have plenty of soap. We've got scrubs, salt bars, sniffing jars, lotion bars, lavender wands, books, magazines and all kinds of herbie stuff. But here's the soap.
They come in other colors, including 'Tangerine Gem' and 'Orange Gem'. I bought one of the other varieties. The 'Lemon Gem' was the runt and it has come on gangbusters over the other variety. They are as I mentioned an edible flower. I decorate my pasta salad with cherry tomatoes and 'Lemon Gem' marigold flowers. A very pretty combination. You need to remember to eat only organically grown flowers and only eat the petals, not the pollen in the center of the flower. This flower also makes a lovely hedge of flowers when placed together in a row. Enjoy these last days of summer!
There is a beautiful rose bush that I love and couldn't be without in my garden. It is called 'The Fairy'. I got mine through Heirloom Roses in Oregon. I looked at their website and found they have two sports of 'The Fairy'. One called 'Crystal Fairy' that is a white sport and the other is called 'Lovely Fairy' which is a lightly fragrant deep pink or light red (in cool weather). There was a third called 'Fairy Queen' which is a double dark pink to red polyantha rose. Here are a couple pictures of my 'Fairy'. They are wonderful in a tussie mussie and also to decorate a cake or a dessert platter. Remember they are an edible flower. Make sure you remove the pollen and other reproductive parts and the white heel at the base of the petal.
Most herbies use vodka, but not all. Brandy is used, whiskey, and sometimes whatever is in the house. I've been known to grab gin or rum if the herb was ready and that was all that was available. It is more about the alcohol, and the ability to preserve. If grain alcohol is used (not available in my state), add some water to the mix because most herbs need some water in order to extract well. Half and half is a good blend. Personally I use the cheap vodka because chances are I will go through a couple of gallons in the fall. This doesn't mean that I'll actually use all of that tinctured vodka over the winter, but I will have lots to share with my family and friends as the cold and flu season goes on. Elderberry - I make at least a quart! Holy Basil - that's another quart or more. And then there is Echinacea, Chamomile, Passion Flower, and Vitex. I could go on and on - but you get my drift. 
There are varying opinions on how long to allow tinctures to sit. Some people tell you to shake it daily, as well. So, I'll tell you my method, and you can come up with your own.
Sterilize a quart jar for 10 minutes with boiling water, then add your herbs and white wine vinegar or red wine vinegar. I would not use white distilled vinegar. Only use that kind of vinegar for cleaning. I also would not use apple cider vinegar either.
But lower, closer to the ground we found some glossy leaves that bugged me. They looked like something familiar... that way that plants I've studied in field guides over the years do, when they've never actually turned up during any outtings. In other words, those I've yet to find.
I reached down and crushed a leaf to sniff...Wintergreen! Ah!!! A Bazillion plants scattered over a few acres! And me without my camera. The berries taste just like wintergreen candy, but not quite as sweet. We dug a few plants, and I brought them home with the intent of getting a patch going here. I wish that I'd picked a lot of the leaves and saved them for tea, but it's not that far to return...
As I pinched, the whole thing came up, and the roots are underground runners that were buried lightly under decayed leaves. I hope it survives, as it will be planted out first thing in the morning.
They moved on to the Big Apple within a couple of years, but our friendship endured and they even hosted us during many trips to the wholesale shows while we had a shop to stock. In fact, we started attending shows like "the boutique show" at Javitz just so we could spend a weekend AND buy some cool clothes for the shop.
so it was a great surprise to hear that Robbie would be spending a week in a nearby town on business, and Laura would be able to zip over here during the day while she spent some time with him.
We had a great time. First some hugs, then (of course) down into the woods.
Later we went in to downtown Mount Joy for a bite to eat. Molly couldn't get off school that day because of a field trip, but fortunately she got back in time for a hug.
I must apologize to Toby Myers, proprietor of The Tilted Kilt. It's been over a week since we've been there and I can't remember what everyone ate. 
All I can say is that we ALL enjoyed the meal thoroughly and the dessert that we shared was delicious! 
, Richo Cech