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Earth Air Fire and Water
The Pharmageddon Herbal
Ivor Hughes
Chapter 10A
The Extractions

Introduction
Yet it happens that many herbs grow without having been sown, and these are often the best. There are also many important species that are better than those that are sown. Such is the power of the earth, and such is the power of nature; they do not rest. Therefore give heed to your inner garden, and also to yourself that you may learn that which no one can teach you, and which will amaze everyone.
Paracelsus.

Paracelsus was without doubt, the Father of Western Bio-Chemistry. He stated that life was a Chemical reaction. This nearly 500 years ago. From the greatest far flung Galaxies � to the Virus seed of life � that is an observable fact. When we exhale, or draw breath, it is a chemical act. When we eat and excrete, it is a chemical act. Molecules forming, breaking and reforming, and transmuting the elements. All at dazzling speed and low temperatures, the reactions flaring and subsiding like meteors flashing across a night sky.

The remedy is nothing but a seed, which you must develop;
Into that which it is destined to be.

Paracelsus
Man and His Body.

Disease or in its original understanding of the word, Dis-Ease, gives a pithy understanding, that covers a mild headache through the almost unendurable, nerve breaking pain. It is core concept that we are made from the elements of earth passing through many levels of being, rather like the many stages of becoming a butterfly. Or a bud becoming an apple. Such is the power of Nature.

Everywhere we look in nature, from micro to macro, we may see magnificent order. When all is in balance � when the metabolism � anabolic and catabolic, are at equilibrium � then order is maintained. It is well recorded, that residents of areas which are deficient in some trace element suffer from various types of metabolic disorders caused by an imbalance.

Further, those dis-orders may be corrected by making good the deficiency. For example iodine in salt. Sea salt is best. Our bodies have an affinity for it. Paracelsus was Physician for the Fugger Mining Company, and made a first hand study of the diseases that those miners suffered from. This in category of ore or metal that was being mined.

Each of the different organ systems of the body, are ordered by the glandular system, and its secretions. A deficiency of vital, bio-chelated (passed through a plant) trace elements, will lead to a malfunction of the organ systems involved, this at the cellular level.

Nature is not concerned with clinical trials, and inadequate statistical verification. Synergy simply means, right amount, in the right place �� at the right time. Nature has solved that problem nicely and delivered the goods in gift wrapping. Which we remove, and store the contents for further use. It only remains to select the remedy, and determine the dose �. Or is it ?

Spagyric Pharmacy would say, definitely not. For the reason � that the Galenic extract, is incomplete � it is minus the plant cell salts. Those salts are vital to the correct functioning of the remedy. The plant cell salts will make good, any deficiency, of those salts, within the cellular structure of the organ system, for which the remedy is intended. Thereby ensuring, correct organ, and related organ response. This type of response is a synergistic response.

The reason � the plant cell salts are the same as human cell salts. The plant has already done the work, the human cell does not have to put the salts through a production process before assimilation. The physiologic response when taken on an empty stomach is swift. The speed of assimilation may be modified, by taking the remedy with food, or after food.

The art and use of extractions is very old, lost millennia. Rinsing clothes in a brook is an extraction process. A vegetable soup is a decoction of vegetables. A sweat lodge or a sauna are extraction processes. Then slowly as the age of stone declined and the knowledge of metals seeped through the peoples �.. little seed pearls �. perhaps dropped at a shelter on an old trade route. Then the technology improved, as the metals extended our reach. Today, just as then, we have access to all manner of fine things. Healing Medicines. Food flavourings, inks, dyes, cosmetics and perfumes, fumigants and antiseptics.

-::-::-

The Types of Extract 10.1
The base form of all extracts is liquid and are classified into types as follows;

A. The Liquid Extract is the strongest type of plant liquid made, its ratio of the plant material to solvent is 1:1, i.e., 1 gram crude drug represents 1 ml of the liquid extract. For technical reasons it may only be further concentrated by evaporation of the solvent. Occasionally a 1:2 preparation, i.e., 1 g crude drug equals 2 ml liquid is called an extract, this is incorrect and leads to confusion. When the term extract is used in this text, it means a 1:1 preparation.

B. The Tincture is the most common form of plant liquid. An official definition of a tincture is that it has a drug/solvent ratio of 1:4 and that the solvent be a minimum 45% by volume. There are some difficulties with that definition because there are strong tinctures, i.e., 1:2 or 1:3 or they may

go from 1:5 through 1:10. International protocol on potent plant drugs, e.g., Belladonna, Digitalis, Strophanthus etc. is agreed upon 1:10. The international protocol was established for obvious reasons. Preparations above 1:10 are little more than preserved concentrated infusions that will be covered later in the text.

C. The Essential Oils represent a fraction of 1% of the total plant constituents and are not representative of a plant�s therapeutic range. They are undoubtedly the finest of natural antibiotics, which because of their potency can be dangerous in the wrong hands. If taken internally they can be extremely toxic, and if used without dilution externally, damage to the tissue can result.

D. The Expressed Plant Juices enjoyed a vogue in the early years of the 20th century but were gradually abandoned because of their limitations. They are brisk and vigorous in action, which may be attributed to the live enzyme content and as such, bear comparison with fresh fruit and vegetable juices. Not the least of these problems are those pertaining to dose (Posology) restraints must be adopted otherwise harm may result. The preserved juices are problematical.

E. The Concentrated Infusions and Decoctions are prepared with water as the solvent. If taken in that form they are classed as recentium (recent) or alternatively they are preserved with alcohol 20%.

F. The Pasty or Dry Extracts
are prepared from liquid extracts by evaporation. They must be prepared with extreme care lest irremediable damage occurs. There are three types;

(1) Soft. (2) Semi-soft. (3) Dry. They are the basis of pills and ointments.

Methods of Preparations, Table 10.1A

Procedure A.. B. C. D. E. F.
Pressure     X X    
Solvents. X X     X X
Distillation     X      
Pulverizing       X    
Evaporation           X

Extraction Procedures 10.2
The term
�menstruum� is interchangeable with the term �solvent�. The term �marc� in a general sense means the exhausted crude drug and therefore will also contain any other insoluble residue such as the proteins, e.g., albumins and globulins. The procedures for the extraction of crude drugs will with minor variations conform to the following procedures;

Table 10.2A

(1) Authentication of origin and nature of cultivation regimes.
(2) Sampling and organoleptic assessment of the drug.
(3) Size reduction (comminuting) of the drug.
(4) Extraction by appropriate means.
(5) Clarification by sedimentation and/or filtration.
(6) Adjustment of extract to a defined strength.

The procedures shown are in the order of the required operation.

Authentication of Crude Drugs 10.3
The commerce in crude drugs
is a significant item of global trade. Crude drugs are exported to and imported from every continent. At source they may originate as a product of cultivation, or be harvested from the wild. In the crude state they are represented by all parts of the vegetable kingdom. Woods, barks, seeds, buds, flowers, leaves, whole plants.

As a pre-treatment, items of awkward shape may be coarsely chopped, lightly crushed or finely ground, to reduce the volume for packing and shipment. In other instances the crude products are essential oils, gums, resins and a variety of inspissated juices (made thick by evaporation) such as aloes.

Many of the products involved are traded on the world commodity markets, notably New York, London, Amsterdam, Hamburg and Tokyo. As such they are items of financial speculation and may be held in warehouses for up to four years in less than ideal conditions.

If items are products of cultivation, there is also the very real problem of heavy metal and toxic spray contamination from the cultivation regime. Many substances used are systemic, i.e., absorbed by the plants.


This is not such a concern if the materials are wild crafted, however all such products, if they cross national borders, will need a phyto-sanitary certificate. A certificate will not be issued without proof that the shipment has been irradiated or fumigated.


The fumigation procedure
is carried out with toxic gases, residues of which, remain on the treated materials. However of even greater concern because detection is either difficult/expensive or not possible, is the use of gamma rays to irradiate biological products.


Herbs and spices
are among the very few products that may be legally irradiated. The danger of gamma ray irradiation lies not in the radiation but in the molecular changes that occur in the bio-substances subjected to the treatment.

There is research evidence that suggests that the changes are implicated in the onset of degenerative disease in humans and animals that ingest such substances. Finally there is the age-old problem of adulteration and substitution of materials. These potential problems may be avoided by dealing with known organic growers or trading companies. Obviously this is not always possible, however a reputable supplier can provide a history of the materials sold. The minimum information required is as follows.

                                1. How old is the material, i.e., month and year.
                                2. Is it cultivated or wild crafted, i.e., sprayed or organic.
                                3. What is its country of origin.
                                4. How and at what temperature was the material dried?

Sampling of Crude Drugs 10.4
Scrutinizing a large batch
of a crude drug in its entirety, is not feasible. However, it is necessary to have a system of sampling which will give a reasonably accurate picture of a batch condition and quality. The following method, with some small variations is that which is employed by all of the large drug houses. By adopting and adapting it for your own requirements, the accuracy achieved will meet most requirements.

When receiving a consignment of crude drugs they may be re-packs, the original packs have undergone a cleaning and grading process. After this they may be re packed, either into packs of the same weight as the original, or the bulk may be split into more convenient weights for onward sale. For example a shipper or major drug house would be more likely to offer the goods in the original pack size, e.g., 80 kg, 50 kg, 25 kg, etc. Whereas a wholesaler who supplies to retail trade will break bulk, e.g., 5 kg, 1 kg, 500g.

Original Packs and Repacks 10.5
To sample original packs you will need a core sampler. This device is similar to the domestic apple corer but much larger. For pack sizes from 100 kg to 25 kg a sample should not be less than 250g per pack.

The core sample should first be taken vertically through the sack, then horizontally, ensuring that the sample is from the central area of the pack. For packs from 20 kg to 5 kg the sample should not be less than 500g for the total.

Sampling Small Packs 10.6
For packs of 4 kg and under a sample should consist of not less than 25% of the total weight of the pack. This is done by hand and the sample weighed

Sampling Irregular Pieces 10.7
Core samplers are only of use if the crude drug is powdered or in pieces of 10 mm or less, e.g., seeds, powders or rubbed herb. Roots, rhizomes, stalks, leaves and petals are sampled by hand with the sample being taken from the core of the pack.

The Representative and Official Samples 10.8
For recording purposes
the sample taken thus far is the representative (of the batch) sample. From this, the official sample is taken.

If the product is to be consumed, or used by another individual, the producer has legal as well as ethical obligations relating to the product. If there are problems arising down the line then you will need to justify your procedures. In practice this means, that your official sample, and the procedures followed, and your report on the sample, must be stored for a minimum of 12 months, and be made available upon official request. It is the responsibility of the individual to ensure that their procedures comply with the law that prevails, in the country from which they operate.

The official sample must weigh not less than 125g, this being the smallest amount required for official test protocols. Accordingly the representative sample should not be less than 1 kg if the official procedures are to be followed. Obviously there will be occasions when for various reasons that quantity will not be available. Therefore, the official procedure must be modified. The reason for modification should be stated in the report.

Let us assume a representative sample of 1 kg. The sample is thoroughly mixed and then spread out on a clean surface and then quartered. Two diagonal quarters are retained and two rejected. The retained quarters are again thoroughly mixed, laid out and quartered. Again two diagonals are retained and two rejected. The remaining 2 quarters comprise the �official� sample or 250g of the original 1 kg.

The Physical Examination of Samples 10.9
The physical examination
should be carried out in daylight and with the assistance of a hand lense. The first procedure is an organoleptic assessment of the material, write your impressions into the report, e.g., what is the color, is it bright, dull, etc. How does it smell? How does it feel, crisp or damp? Is it characteristic of the material?

Now spread the material on a white flat surface and scrutinize it with the lense; is there any obvious admixture of a different type or part of a plant? If so then try to separate it out. Normally this must be done by hand, but the use of a small spatula will make the task easier. If foreign plant material is present, separate it out and carefully weigh it.

Next examine the remaining sample for other adulterants such as insect parts, rodent or avian excreta, stones, etc. Then carefully weigh the remaining cleaned sample. Finally determine the percentage of the foreign plant material relative to the cleaned sample, for example;
 

   Original sample 250g.
          Foreign plant material 3g.
Foreign material 1g.
  Cleaned sample 246g.
Therefore:  3 divided by  246 x 100 = 1.22%

The upper limit for foreign organic material is 2%. If the sample is above that level, it must be discarded. Next determine the percentage of foreign material present as it relates to the whole sample;

Therefore:  1 divided by  249 x 100 = 0.4%

That figure is 40g/kg therefore the material will need to be further cleaned before extraction procedures are commenced. On the assumption that the material meets the other organoleptic criteria, it is then prepared for the extraction process.

Other Test Procedures 10.10
Regarding those matters discussed in Paragraph 10.3
it will be realized that materials sourced from growers, within ones own national borders, allow the Herbologist greater control of the materials handled. Contact with a grower that employs organic cultivation methods will render unnecessary any further analytic testing. Remember that only the arbitrary standardization procedure is used, therefore only a brief discussion of those tests will be given. A more detailed coverage of test protocols will be found in the appendices of the National Pharmacopeias and in particular those of the European Pharmacopoeia. These type of publications for most countries, will be available via the public library network

Analytic Protocols 10.11
Herbs and spices
have always loomed large in human food behavior. With the turn of the 20th century came large scale food processing and preservation methods that of necessity had to resort to herbs and spices for flavor and preservation purposes. Consequently there have been many attempts at setting universally applied standards that have so far only met with limited success due to the number of variables involved and the nature of the material.

The Tests 10.12
The tests are both qualitative and quantitative
. If we talk of analysis, we mean all those tests involved in the qualitative and quantitative procedures.

If we talk of an assay we mean a truncated version of the total, i.e., those procedures carried out in a laboratory and are mainly concerned with quantitative aspects, i.e., � how much is present� of a given substance.

The results can be used as a �Guesstimate� as to whether the plant is what it claims to be, and that it meets a given quality criteria, i.e., the levels of given substances fall within certain limits, similar to a human blood or urine test.

It must be clearly understood that �biological idiosyncrasy� allows for no absolutes so that even if a given substance is under or over predetermined limits that no dogmatic statement can be made as to efficacy of a plant. We can only say �that based on probability� the plant will, or will not reach a set standard of performance.

The procedures used are a combination of gravimetric and volumetric techniques. The techniques are either classic or instrumental. In the late 20th and early 21st century, instrumental analysis is the norm, i.e., the procedures may be carried out by technicians rather than a chemists, however both methods are based on gravimetric and volumetric techniques. As a general rule, the tests employed are as follow;

1. Macroscopic and Microscopic Examination. Traditionally these procedures fall under the head of Pharmacognosy, and the histological characteristics of the plant are examined, e.g. for roots, the size and shape of starch grains, are of importance. For leaves, the number and size of stomas are examined. The sampling procedure is as previously covered. Full details may be found in a standard text.

2. Loss of Moisture on Drying. These procedures are usually carried out on previously dried material. Equilibrium moisture content has been covered in the Module dealing with Dehydration. If the material is obviously damp then it will be above equilibrium moisture content and should be considered unfit for use. Undoubtedly it will yield a high plate count of microorganisms and catabolic enzyme activity will be in progress.

3. The Ash Tests are of two types. The first is the total ash found after calcination of the plant and the second is derived from the first. The total ash is treated with hydrochloric acid. The residue remaining is the �Ash Insoluble in Hydrochloric Acid�. The tests are used to find in what quantities, elements are present, therefore they can be used for heavy metal contamination tests.

4. Water Soluble Extractive. Extractive tests are based on the solubilities of the various menstruum employed and will yield qualitative and quantitative information on the plant under tests.

5. Ethanol Soluble Extractive. The remarks for water also apply here.

6. Ethanol Insoluble Extractive. This usually refers to precipitated residues such as albumins and globulins etc. They are separated by filtration then dried and weighed, the percentage calculated against the air-dried drug.

7. Volatile Oil Content. This test is a sophisticated micro version of the far larger commercial operation. The results are calculated as milliliter of oil per 100g of the drug. The test may be used to produce oil for other types of testing, e.g., fractional etc. and is also used as a quantitative procedure.

8. Analysis of Active Constituents. The analysis of plant material can be carried out in one of two ways; the first is classical analysis.

The object of an assay is called the �analyte�. The methods involve quantitative methods, e.g. gravimetric or volumetric measurements, specific gravity and pH measurements. The qualitative assay is carried out by inducing a chemical reaction or a series of reactions between the analyte and another chemical or a mixture of chemicals called �reagents�. The reaction may be seen either as a liberation of a gas, the deposit of a precipitate or a color change.

The second method is instrumental analysis, by which many tasks are rendered routine and downgraded to technician level, thus freeing up the chemist for more rewarding tasks.

Instrumental methods employ both quantitative and qualitative techniques. Also important in plant analysis is the spectral and separation methods employed in chromatography.

Crude Reagent Tests 10.13
Nowadays there is a greater appreciation by natural science, of the synergistic effect of a total plant complex and not so much emphasis is placed on an isolated �active principle� because every plant, whether it has recognized medicinal properties or not, will exert a physiological effect to a greater or lesser extent if ingested.

Total analysis, if it is possible, will be both lengthy and expensive and may involve the services of 2 or 3 skilled chemists. Consequently much plant material that passes through pharmaceutical company laboratories has only received a crude perfunctory screening in field conditions to decide whether or not, to investigate further.

The field or bench test usually centers on a probe for a particular type of constituent or functional group, e.g., alkaloids or glycosides. These simple tests do no more, than indicate the presence or otherwise of the group in question. Plants do not contain, in isolation, single alkaloids or glycosides. If they are present they will be so as a complex of different types. It is quite simply a matter of adding a specific reagent which is known to react with a particular functional group and observing the change, if any.

A Simple Test for Alkaloids 10.14
The test may be carried out on fresh or dried material. If the material is dried it should first be moistened with 25% dilute alcohol and allowed to swell, then proceed as follows;

Use a mortar and pestle and reduce 3 to 4g of the material to a paste using sufficient 25% alcohol to do so. If the material is fresh add a little clean washed sand to the mortar to help in making the paste. Smear the paste onto a clean filter paper and allow it to dry. Remove the dried paste and treat the stained filter paper with Dragendorff�s reagent. Dragendorff's reagent (solution of potassium bismuth iodide) gives an orange coloured stain when alkaloids are present.

Testing for Glycosides 10.15
The simple test for alkaloids
may be employed in a similar manner for glycosides. When the filter paper is dry, remove the paste, then add a few drops of antimony chloride to the paper and warm it gently over a light bulb. If the spot turns brown, it denotes the presence of cardiac saponins. If they turn purple, it denotes the presence of cardiac glycosides. The glycosides are notoriously unstable, and will be quickly broken down by enzyme action or by water (hydrolysis). The living plant arranges matters to suit its own economy and enzymes that hydrolyze glycosides are kept separate within the body of the plant. Therefore the value of alcohol as a solvent cannot be overstated in that it inactivates enzymes, and prevents hydrolysis. Indeed in this simple test all we reveal is the breakdown product of glycosides.

The Principles of Size Reduction 10.16
The methods of size reduction (comminution) and the sieves employed in the classification of particles obtained are treated in a previous module. A major factor in the solubility of a substance is the amount of surface area exposed to a solvent. The greater the exposed surface, the faster and more complete is its entry into solution, e.g.,

Surface Area. Figure 10.16A
The cube has 6 sides each side is 100 cm2
Therefore:  area exposed is 6 x 100 cm2 = 600 cm2.

We slice the cube into 8 equal portions.

The surface area for each cube is 6x 25 cm2 = 150 cm2
Therefore:  8x 150 cm2 = 1200 cm
2

We have doubled the surface area. The degree of comminution required will also depend on the composition of the crude drug, e.g., is it hard or soft? Is it thick or thin? If the drug is leaf or petal then it will be easily penetrated by the solvent, therefore the degree of comminution need not be great, whereas hard and woody substances will require a greater reduction in size. Some substances such as aloes or gum resins need only be crushed, and it is a matter of becoming familiar with the material being operated on.

 

 


The following categories will serve as a general guide.

1. Broken or Crushed. Gums, resins and inspissated juices. Most seeds and fruits.

2. Sliced or Small Cut. Rinds, skins, pith, stalks.

3. Rasped. This type of size reduction is of dubious value and is only officially used for quassia that is a hard wood. From personal experience the tedium may be avoided by pulverizing such substances.

4. Powders. Rhizomes, roots, barks, woods, corms. There are 5 official grades of powder.  .........................

........................................................................................................................................................................

 

Table 10.16A

1.  18 mesh Coarse Powder.
2.  25 mesh Medium Coarse.
3.  45 mesh Moderately Fine.
4.  80 mesh Fine Powder.
5.  120 mesh Very Fine.

For extraction purposes we may ignore the 80 and 120 mesh with the 25 and 45 mesh being most often used.

The final consideration for the degree of comminution needed, is the menstruum or solvent to be used for the extraction. Remember that our solvents are water, alcohol or a combination, i.e. dilute alcohol.

The tissue of crude drugs in the dried state will contain around 4 to 5% moisture if it has been properly conditioned, therefore if water or a dilute alcohol is used as the menstruum it will penetrate and spread rapidly through the plant tissue; whereas strong alcohol, i.e. 50% by volume or over in the initial stages will cause shrinkage or hardening of the tissue because the water is pulled to the surface thus shrinking the interior. This phenomenon may be explained by the fact that ethanol molecules have s hydrophilic (water loving) tail, i.e.,

The hydroxyl group is electrovalent (polar) and will attract water.

Water is also a polar molecule, and its oxygen atom will be attracted to the hydroxyl tail on the ethanol. The result is a slower diffusion of solvent through the tissue. Having regard to the general Table of Solubilities 8.50A our choice of menstruum is constrained by the chemical composition of the crude drug, for example it is pointless to attempt to extract resins with 25% alcohol. Accordingly as a rule, we can say that the greater the alcoholic strength of the menstruum, the finer the division of the crude drug. In practice this means that all substances that require a menstruum of 45% alcohol and over will need to be graded through a 45-mesh sieve. For menstruum�s below that strength, then 25 and 18 mesh sieves will serve the purpose due to the rapid diffusion of water through the substance.

The Extraction Process, 10.17
There are seven extraction processes in general use. They are;

Table 10.17A

1. Infusion. Water
2.   Decoction Water
 3.  Maceration. Alcohol. Oils/Water
 4.  Percolation. Alcohol.
 5.  Macero - Percolation. Alcohol.
 6.  Continuous Hot Extraction. Water - Salts only.
7.  Distillation. Steam and/or water.

Each process will be dealt with in turn. The infusions and decoctions are no longer official, they are not considered reliable for some very good reasons, which are;

                                    1. The extraction is incomplete. (Efficacy)
                                    2. The water and heat involved promote hydrolysis.
                                    3. Prone to contamination by microorganism.

However, for information purposes the prior official methods are given. All the process operations described are carried out on single substances. The student is now in possession of sufficient information to understand the chemical and physical reasons why this is so. If the student attempts to combine the products of the extractions, they will see the chemical and physical reactions that occur. If the student uses glycerine or acetic acid as a part, or whole of a menstruum, they will observe a breakdown of the synergistic plant complex. We cannot play games with Nature around the test tubes.

To combine two or more crude drugs is to destroy the natural synergy of them all. The chemical groups of each plant, when reacting with each other, produce unpredictable results. We have no means of knowing the consequences, and neither can we in this case resort to Empiricism to explain away the anomalies. The evidence of this destruction is clearly visible when we combine two or more tinctures. The abomination that results from the use of acetic acid or glycerine is also plainly visible. 

The Infusions 10.18
The infusions
(Infusa) are of two types. The first is the fresh (Recentium) infusion. Before dealing with the procedure there are some points that are common to all such preparations;

(A) Strength - 5%, i.e., 1:20 = 50 g per litre. (D) Length of infusion - 15-30 minutes, depending on substance.

(B) Solvent - Hot or cold distilled water. (E) Length of storage - Maximum 12 hours.

(C) Degree of comminution - 18 or 25 mesh.

Under no circumstances should infusions of potent drugs i.e. those that are subject to international protocols, be made for the purpose of therapy. In choosing a hot or cold process, remember that some drug constituents are damaged by heat and balance this with the fact that solubility will increase with temperature. A woody substance will require a lengthier infusion than that allowed for a leafy substance.

The infusion should be prepared in a heat resistant glass, porcelain or stainless steel vessel. It should have a close-fitting lid to prevent the escape of volatile principles such as essential oils. For convenience and ease of handling, enclose the comminutated drug in a muslin bag. Other materials of a closer weave tend to absorb the essential oils. The bag should be of such size to accommodate the expansion of the drug. Bags must be kept scrupulously clean to avoid problems of cross contamination. Proceed as follows;

1. Scald the vessel with boiling water; rinse and quarter fill the vessel with boiling water and allow to stand for 2 or 3 minutes or until the vessel is thoroughly warmed through.

2. Empty the vessel then add the comminutated drug and pour on the requisite amount of boiling water. Cover the vessel tightly and allow to infuse for an appropriate time. Agitate the vessel 2 or 3 times during the infusion process.

3. On termination of infusion, remove the drug and lightly express the liquid it contains. Pour the liquid into a clean graduated container and adjust to the requisite volume with distilled water.

The preparation should be kept covered and used within 12 hours. If smaller or larger quantities than 1 litre are required then any adjustments should be made on the basis that the preparation conforms to a 1:20 strength.

The Concentrated Infusions 10.19
The second type of infusion
is the �Concentrated Infusion�. These preparations were first introduced into the British Pharmacopoeia in 1898 under the head of �Liquors�. That designation was withdrawn in the 1914 B.P. and they were renamed as �Concentrated Infusions�.

The major use was as �stock� item, from which a pharmacist could prepare the standard infusion by dilution with distilled water. The ratio of drug to water was 1 : 2.5. As a preparation they stand as an archaic monument to pharmaceutical ingenuity, that involved double and triple maceration to avoid excessive amounts of menstruum that would need to be evaporated to achieve the required concentration.

The heat required would damage the preparation and would also result in the loss of volatile principles during the evaporation process. After concentration the preparation was adjusted to volume at 25% alcohol to preserve it from deterioration. The practicalities involved in the preparations were problematical, briefly the problems are summarized as follows;

(A) Water alone promoted hydrolysis and could only achieve partial extraction of the plant constituents, i.e., it is not possible to exhaust the drug.

(B) For drug plants that contained essential oils the solutions were supersaturated i.e., the oils could not be held in suspension.

(C) The degree of expansion of the dried crude drug in the majority of cases meant that the drug/menstruum ratio was insufficient to achieve even a partial extraction.

(D) The evaporation of water requires prolonged high heat therefore it was not possible to achieve concentration to standard without unacceptable damage to the drug constituents, therefore extraction by percolation was not an option.

All of this placed the practicing pharmacist in a quandary, i.e., they had to serve two masters; on one hand there was �Authority� in the form of a �Legal� standard as represented by the �Pharmacopoeia� and on the other the �Physician� whose practice can rarely keep abreast of research; whose prescription was also a �legal� order, and who long continued to prescribe infusions contrary to the advance of knowledge.

A compromise was reached by which the extraction was achieved by dilute alcohol at a strength of 25%. Even this was not really a satisfactory answer because invariably the dilution with water required to produce a standard infusion produced precipitation and/or turbidity due to the change in menstruum strength. So not surprisingly such preparations were slowly displaced as �official� standards were changed i.e., tacit acknowledgment that such preparations were lacking in efficacy. The prolonged boiling for the preparation of �Decoctions� is contraindicated.

 

The British Herbal Pharmacopoeia, 10.20
The British Herbal Medicine Association in their quasi official publication the British Herbal Pharmacopoeia has reintroduced the concentrated infusions under the term �liquid extractions�.

The preparations conform to the �official� designation in that the drug/menstruum ratio is 1:1, i.e., 1 g is equivalent to 1ml. However the menstruum lacks the solvent power of that of a true extract and in that respect are inferior to the official �tinctures�. This may be seen in the following short Table representing a small sampling from the 233 monographs contained in the BHP 1983.

Table 10.20A

Designation. Drug. Ratio. Menstruum. Dosage.
BHP Extract Virgaurea 1:1 25% Alcohol 0.5 - 2 ml
Orthodox Tr. Virgaurea 1:5 45% Alcohol 0.3 - 1 ml
BHP Extract Lappa 1:1 25% Alcohol 2 - 8 ml
Orthodox Tr. Lappa 1:10 45%Alcohol 8 - 12 ml
BHP Extract Plantago 1:10 25% Alcohol 2 - 4 ml
Orthodox Tr. Plantago 1:5 45%Alcohol 2 - 4 ml
BHP Extract Potentilla 1:1 25% Alcohol 2 - 4 ml
Orthodox Tr. Potentilla 1:5 45% Alcohol 2 - 4 ml
BHP Extract Pulsatilla 1:1 25% Alcohol 0.12 � 0.3 ml
Orthodox Tr. Pulsatilla 1:10 40%Alcohol 0.3 - 1 ml
BHP Extract Tillia 1:1 25% Alcohol 2 - 4 ml
Orthodox Tr. Tillia 1:5 45%Alcohol 1 - 2 ml.
BHP Extract Viscum 1:1 25% Alcohol 1 - 3 ml
Orthodox Tr. Viscum 1:5 45%Alcohol 0.5 ml.

It was formerly a �convention� of orthodox pharmacy that in preparing a crude drug that was not �official�, i.e. one for which there was no monograph in the pharmacopoeia then a concentrated infusion was �sine qua non� which is from the Latin, meaning, "without which, not". Obviously the scientific committee who worked on behalf of the BHMA have chosen to continue that convention in spite of the fact that there is now a wealth of information available for most of the crude drugs listed in the BHP.

Choosing an Appropriate Extraction Process 10.21
When considering a crude drug for extraction purposes thought must be given to whether the drug is classified as �organized� or �unorganized�. If the drug has no clearly defined cellular construction it is unorganized. The maceration process is the only method suitable for unorganized drugs such as gums, resins, oleo-resins etc. Such materials are unsuitable for percolation because the residues would block the percolation process. The same restriction will also apply to crude organized drugs that produce large amounts of mucilage e.g. flax or Psyllium seed.

In other cases if a drug for whatever reason cannot be reduced to a powder then it is not suitable for a percolation process. Some drug materials e.g. Garlic and Squill are extremely hygroscopic and in the presence of water tend to fuse into lumps which make them unsuitable for the percolation process.

Extraction by Maceration 10.22
In a chemical sense the term �maceration� means to �soften and separate the constituent parts of a substance in a liquid�.

The alchemical or hermetic term for the process was �digestion� and it differed from the orthodox process in that the digestion was carried out at a constant low heat. i.e. a temperature not below 25�C or exceeding 35�C.

The Spagyrist had no thermometer, and judging the fire too fierce, would embed the digesting flask and its contents in horse dung. To ensure a constant and even gentle heat which is produced by fermentation of the manure.

We of course may also use a thermostat. At night fall the Spagyrist would remove the flask from the dung and allow it to cool in the night air. At sunrise the flask would be replaced in the dung. We simply turn off the  heat.

The process of digestion was continued for either a lunar month of 28 days (4 x 7) or a philosophical month of 40 days. The precise period was judged according to the work to be accomplished.

It is usual for the orthodox preparations to be macerated for a period of 7 days; in the language of alchemy this was a 7 fold circulation. The maceration is carried out at room temperature.

Tinctures by Maceration 10.23
Prior to the introduction of the technique of percolation, maceration was the universal method of producing strong extracts of crude drugs.

The results varied widely until reliable methods of assay allowed such tinctures to be chemically adjusted to the known level of a single �active� constituent.

The following is a description of maceration, which is the general process given in the various issues of the British Pharmacopoeia.


Place the solid materials with the whole of the
menstruum in a closed vessel and allow to stand
for 7 days, shaking occasionally . Strain, press
the marc, and mix the liquids obtained. Clarify by subsidence or filtration.

The general method employed in the United States of America corresponded to the following description;

Macerate the drug in 75% of the menstruum, agitating regularly over a period of 3 days or until the extraction is complete. Transfer the mixture to a filter. When the liquid has drained wash the filter with the reserved portion of the menstruum, press the marc and adjust the filtrate to 1000 ml and mix thoroughly.

When comparing both methods it will be seen that the British process omitted to adjust the tincture for volume. This was not an oversight on the part of the BP and the process took account of the different methods employed to �press the marc� so that uniformity of strength in the finished product was maintained. For example;

Table 10.23A

Required Volume 1000 ml.

Volume obtained by Expression of Marc.

Drug/menstruum ratio 1:10

By hand *

Screw press *

Hydraulic press *

Strained liquid

850 ml

850 ml

850 ml

Expressed liquid *

30 ml

70 ml

130 ml

Volume of liquid

880 ml

920 ml

980 ml

Total as % of volume

88%

92%

98%

With the proviso that the volume is not adjusted to 1000 ml, then uniformity of dose is maintained. Whereas using the American method, whereby the preparation is adjusted in each case to 1000 ml, then the percentage weight in volume of the drug for each method of expression will alter thus uniformity does not exist for dosage purposes.

It must understood that this is no small matter in terms of potent drugs. Such variations could have tragic consequences. The therapeutic index of a drug may show a very small margin between effective (ED) dose and lethal (LD) dose.

For the Homeopath such variations are greatly magnified, and make a nonsense of diagnostic posology and the potentising process. It may be seen from the British process that even by use of a hydraulic press that the marc still contains a proportion of the menstruum and the soluble constituents, the proportion of which decreases as the efficiency of the expression process increases.

Unless one has use of a hydraulic press, the product from an organized drug manufactured by the maceration process, at its very best will be variable for Galenic Tinctures. If circumstances dictate that a tincture of an organized drug be made by maceration, use the British method and do not adjust the volume.

Tinctures from Unorganised Drugs 10.24
Maceration is the only feasible method of producing a tincture from an unorganized drug such as gum benzoin or propolis resin.

The marc from the exudates is usually slimy or gummy and may also consist of various types of debris, e.g., insect parts, fragments of soil or plant parts. The gums are insoluble in alcohol while the resins or oleo-resins will pass completely into solution. The gum and debris will sink to the bottom of the maceration vessel.

The separation of the supernatant liquid is usually by simple decantation or if required by filtration. There is no advantage to be gained by attempting to press the marc because all of the soluble constituents have entered into solution. Unlike the organized drug the solution is adjusted to volume.

Summary of Maceration Processes 10.25
(A) The Organized Drug
. The marc of an organized drug will hold around 1.5 times its dry weight of menstruum, e.g., 500g of dry crude drug when saturated with menstruum would weigh circa 2 kg. That is the equivalent of a drug/menstruum ratio of 1:3. Obviously there is insufficient menstruum to extract the drug by maceration. Therefore, a standard tincture is 1:4.

1. Comminute the crude drug as appropriate and place it in a wide neck jar or flask. Pour in the total menstruum and seal the flask. Leave to macerate in a warm dark place.

2. Shake the maceration 2 or 3 times daily for 7 days.

3. After the 7 days, separate the menstruum from the marc by filtration. Press the marc and add the expressed liquid to the separated portion. Seal the flask, shake and leave to settle for 24 hours.

4. Clarify the tincture by a single filtration. Seal the flask and store in a cool place until required. Do not adjust the volume.

Maceration and storage should be carried out in a dark place, as a matter of routine. This because of the deleterious effect of light on the extracted substances, i.e., a catabolic breakdown occurs. Never over filter a tincture or extract lest it is altered or weakened. If after the 1st filtration the liquid is not clear and bright then set the flask aside and allow to clear by subsidence. When required for use take care not to disturb any sediment and remove the liquid by siphon or large syringe.

There have been moves to standardize tinctures by international protocol at a strength of 1:5. This avoids occasional problems of too little menstruum for a satisfactory extraction due to enhanced absorption by some materials. However, many countries follow their own protocols in this respect.

(B) The Unorganized Drug. The major differences in procedures for unorganized drugs are as follows;

1. Crush the material and macerate the substance in 80% of the menstruum specified.

2. Shake the maceration 2 or 3 times daily for 3 days or until solution is complete.

3. Separate the marc from the extraction by filtration. Wash the marc across the filter with the reserved 20% of menstruum. Do not press the marc.

4. Finally adjust the tincture to the required volume by the addition of further menstruum. Uniformity is achieved because extraction of the unorganized substance is almost total.

Concentrated Preparations 10.26
All extracts
below 1:4 are concentrated preparations. At one time such products were prepared by double and triple maceration techniques that are now abandoned, being lengthy in procedure and relatively inefficient when compared with the percolation process that replaced them.

Drug and Menstruum Ratios 10.27
The most common proportions of drug to menstruum are as follows;

Table 10.27A

Ratio

% of Drug

Remarks

1:1 100%  Liquid extracts 1 ml = 1g
1:2 50%  Also classed as an extract 2 ml = 1g
1:3 33%  Strong tincture 3 ml = 1g approximately
1.4 25%  Standard tincture 4 ml = 1g
1:5 20%  Tincture 5 ml = 1g
1:7 14%  Weak tincture 7 ml = 1g
1:8 12.5%  Weak tincture 8 ml = 1g
1:10 10% Homeopathic and Potent Drugs. 10 ml =1g
1:20 5%  Water based. Alcohol as preservative. 20 ml = 1g

It is most important that drug/menstruum ratios are accurately adhered to and all containers from which the preparation is dispensed should be clearly marked with the ratio, e.g., Tr Lobelia 1:8. Remember that the ratio will determine the therapeutic dose of the substance.

Module continues as 10B

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