The following information are from the book of Kerry Bone, Clinical guide to Blending Liquid Herbs. Maybe it's useful to someone...
IMHO I do like to create tinctures in fresh form rather than dried. But this is an article I stumbled upon recently who made me have a second thought about it. To make this short, this study suggests that the medicinal properties of a tinctured herb remain the same, no matter if it is in a dried or fresh form. You may see at the end of this post, a visual comparison between those two liquid extracts. He also suggests, that a dry herb must be our first choice when it comes to tincture a herb for better ratio reasons. I am copying this stuff so anyone, by chance, might benefit from this.
But I would love to hear your opinion! So, this is what Dr. Kerry Bone states:
"...In recent times, the use of tinctures made from the fresh plant has become popular among some herbalists. The belief is often that a fresh plant tincture better reflects the plant’s “vitality” or “energy” and therefore will be a more therapeutic preparation. Other practitioners believe that a fresh plant tincture will better preserve the delicate active components of the plant. On the other hand, the following observations need to be considered:
• The evidence from phytochemical analysis that fresh plant tinctures contain better levels of active components than do dried plant tinctures is generally lacking. In fact, fresh plant tinctures are usually prepared in a low-alcohol environment (see later discussion), which means that some less polar (more lipophilic) components may be only poorly extracted. Furthermore, the enzymatic activity of the plant material may not be inhibited in this low-alcohol environment, meaning that key phytochemicals may actually be decomposed during the maceration process. This fact was dramatically illustrated by Bauer, who found that cichoric acid in fresh plant preparations of Echinacea purpurea was largely decomposed by enzymatic activity.10 Therefore what can be found in the living Echinacea plant was not preserved in the fresh plant tincture.
• Fresh plant tinctures were never official. Although fresh plant preparations were included in homeopathic pharmacopeias (which is understandable, given the energetic considerations in homeopathy), they were never listed in conventional pharmacopeias other than a few entries for stabilized fresh juices known as succi (singular: succus). Hence the use of a wide range of fresh plant tinctures is travel into unknown territory.
• Because of the water content of fresh plant tinctures, making preparations that are stronger than a 1:5 on a dry- weight basis is difficult. This problem can be readily illustrated by the following example. A leafy, fresh plant material typically contains 80% moisture. Therefore 100 g of this material represents 20 g of dried herb. To make a 1:5 tincture, this 20-g equivalent of dried herb must be mixed with 100 ml of liquid menstruum. However, 80 ml of water already exists from the herb itself. Therefore to preserve the 1:5 ratio, only 20 ml of 96% ethanol can be added. This 20 ml of ethanol is not enough to physically extract the bulky 100 g of fresh plant material. However, what is probably just as detrimental is that the effective ethanol percentage is only 20% (20 ml of ethanol and 80 g [or ml] of water from the fresh plant). This amount is too low to extract lipophilic components and barely enough to preserve the tincture. Some authors suggest using multiple maceration to overcome this problem, whereby the resultant tincture is macerated with a new batch of fresh herb, but this only makes the situation worse, diluting the alcohol to below the level that canstabilize the final tincture.
In summary:
• 100 g of a fresh plant containing 80% moisture is macerated in 20 ml of solvent (alcohol-water).
• The dried herb weight is 20 g.
• The amount of liquid is 80 ml (moisture from the fresh plant)+20 ml (solvent)=100 ml.
• Hence the result is equivalent to a 1:5 tincture on a dry- weight basis (20-g dried herb:100-ml liquid).
• However, the result may be even weaker because of the enzymatic decomposition and the low effective ethanol percentage.
Clearly from the previous discussion, given that the water content of fresh leafy plant material varies from 75% to 90%, the only practical way to make a reliable fresh plant tincture is to work on an equivalent dried herb ratio of 1:10. (Perhaps a 1:5 ratio can be achieved for roots, barks, and seeds that contain less moisture.) However, because the use of 1:10 or even 1:5 tinctures makes therapeutic doses of most herbs difficult, the herbal practitioner who endorses pharmacologic dosing will generally find little advantage in using fresh plant tinctures. Some exceptions occur based on traditional use or instances when the herb is so potent that it is normally used as a tincture (e.g., poke root, Thuja), but these are few.From the previous discussion, a fresh plant tincture will never be as strong as will a 1:1 or 1:2 liquid extract, provided that:
a. The liquid extract has been made from carefully harvested and dried raw material of high quality.
b. The correct ethanol percentage was used to extract the dried herb.
c. No steps were used in manufacturing (e.g., exposure to high temperatures) that will damage the delicate active
component spectrum of the plant.
Dried plant preparations made in such a way will still preserve the “vitality” or “energy” of the original plant, which is embodied in its chemical complexity. Fig. 1-1 gives a visual comparison of a dried plant extract (A) with a fresh plant tincture (B) using a paper chromatography technique known as vertical capillary dynamolysis. Adherents to the anthroposophy movement believe this technique can demonstrate the “vitality” of a preparation under test.
Although the analysis of the chromatograms is subjective, the figure does show that a “vitality” to dried plant extracts exists.
Fig. 1-1 A visual comparison of a dried plant extract (A) and fresh plant tincture (B) obtained by a paper chromatography technique (vertical capillary dynamolysis). see at the end of this post!
Some practitioners use fresh plant preparations that are 1:3 or 1:5 (or even 1:10) based on fresh weight in the mistaken belief that they are using highly active preparations. However, a simple mathematical calculation shows that these practitioners are deceiving themselves. Taking a 1:5 fresh weight ratio as an example and assuming again that the herb contains 80% moisture, the following calculations can be made. If 100 g of fresh herb is macerated in 500 ml ofmenstruum, the dry-weight equivalent of herb is 20 g, and the total amount of liquid is 500 ml plus the 80 ml from the plant, which equals 580 ml. Hence the so-called 1:5 tincture is actually 1:29 on a dry-weight basis—completely unsuitable for therapeutic herbal doses."