Common Knowledge:01.What is standardization?
Standardization is a means of determining and expressing the potency of a botanical supplement based on the quantity and identity of therapeutically active compounds that it contains. In most cases, the health benefits of a botanical dietary supplement can be attributed to the presence of biologically active chemical ingredients other than nutrients. While some of these ingredients may have some nutritive value, usually the therapeutic benefits of a botanical results from specific actions of one or more "active constituents" on specific organs, tissues, cells, or components of body structures, such as enzymes or membranes. It follows, therefore, that if a botanical supplement is lacking in active constituents, or contains ineffective amounts, the consumer will derive little therapeutic benefit from the botanical supplement.
The amounts of active constituents in botanical supplements can vary due to a variety of factors, including growing conditions, storage conditions, and the procedures used in extraction and processing.
Standardization is simply the application of various analytical methods to characterize the presence and nature of chemical components present in the botanical supplement or phytomedicine. Usually, the methods applied are various techniques of chemical analysis, such as high pressure liquid chromatography (HPLC) or thin layer chromatography (TLC). Occasionally, pharmacological bioassays may also be used in the standardization process. Standardization ensures that a supplement consistently possesses a measurable, quantifiable, and replicable content of active constituents and/or biological activity.
When the compound or compounds in the plant extract responsible for the therapeutic activity are known and can be quantified, then the extract can be standardized to a specified percentage of active constituents, by appropriate dilution with adjuvant carrier materials. In practice, most botanicals usually owe their activity to a group of structurally-related active compounds, rather than to a single compound, and the extract may be standardized according to its total content of active constituents. For example, extracts of kava kava (Piper methysticum) are usually standardized to 30 or 55% total kavalactones, since kavalactones are known to be the constituents primarily responsible for the muscle-relaxing, anxiolytic properties.
In some instances, when the compounds responsible for the activity are not completely known, or are difficult to measure, the extract may be standardized based on its content of some other constituent which can be easily measured and quantified. The presumption is that when the extract is properly standardized to a key constituent, the other constituents in the extract which are responsible for the biological activity are also present in sufficient quantities. In these cases, the constituent in question is a marker compound; while not itself responsible for the activity, practical experience has shown that extracts containing the compound at a specified percentage have the desired activity (based on clinical studies or bioassay). An example is the herbal antidepressant, St. John's wort (Hypericum perforatum); most commercial St. John's wort extracts are standardized to contain 0.3% hypericin, even though most pharmacognosists now agree that hypericin is not the constituent primarily implicated in its antidepressant activity. Clinical trials have demonstrated that extracts standardized to hypericin are effective, and the compound is a good marker since it is easy to detect and quantify. Both liquid and dried extracts may be standardized, although the practice is more commonly applied to dried extracts.
What is Standardized Extracts?
Traditional herbal medicines include teas (infusions and decoctions), tinctures, poultices and salves. Recently we have begun to make increasing use of tablets and capsules. These are all relatively simple preparations, not highly processed and readily available at very reasonable cost.
Herbal medicine has traditionally been a medicine inherently of the people, for the people, by the people and this is an important distinction between folk healers and allopathic medical doctors. Herbal medicines have always been applied by housewives and mothers as well as by professional clinical herbalists, lay healers and midwives. There is an inherent democracy in this ready availability of herbal medicines - it is non-hierarchical and egalitarian. It is reflective of the intrinsic safety of traditional herbal medicines, given to us by empirical knowledge handed down through millennia from generation to generation and tested again and again on human bodies under all sorts of circumstances. Although herbalism was repressed and refuted, and often branded witchcraft, down through the ages, the knowledge was never quite lost and, indeed, was continually being added to by empirical learning and through apprenticeship
Reductionist scientific orthodoxy has held sway for only about 100 years and it is only 50 years since the advent of modern pharmaceutical science with the myriad of petrochemical-based drugs we know have. This short time has been long enough, however, for millions of ordinary people to realize that most modern pharmaceuticals do not cure the diseases for which they are prescribed and, furthermore, are responsible for a staggering percentage of all hospital admissions.
The public has been hugely disillusioned and they are turning in ever bigger numbers to natural health care products and services. In response the last decade or so has seen the increasing interest of large multinational pharmaceutical companies in herbal medicines. The impact of reductionist science and commercial interests on traditional medicines has resulted in an entirely new form of medicinal product being created -the standardized extract.
This type of product is made by refining and concentrating certain constituents to a specified percentage and sometimes discarding the majority of the plant material to make room in the capsule for the required amount of the specified "active compound". This concentration may be achieved using various solvents and often requiring heat to evaporate away any toxic residues. The end result can be measured and precisely calibrated for exact percentages of constituents. This is considered desirable because it conforms to the requirements of scientific rigor in performing the double blind cross over placebo controlled clinical trial. The standardized extract is a highly processed product, not at all similar to a traditional herbal remedy and more akin to a botanical pharmaceutical.
There are many areas of concern when reviewing the efficacy and safety of standardized products and the results of the trials which use them:
1) So-called active constituents, isolated or synthesized, are not necessarily relevant when reviewed in the context of the whole plant remedy. Tests of function and safety of an isolated constituent may not be applicable to the whole plant. Eg. Salix spp. (Willow) has far higher analgesic and anti-inflammatory powers than its quota of salicylates.
2) In many, if not most cases, tradition and experience tell us how to use a plant but we rarely know what is chemical is actually responsible for a certain action. Where attempts have been made to identify the active constituent, they invariably fail. An example of this is Valerian (Valeriana off.) in which it was thought for some time that the valepotriates were the active component and it was later discovered that there was a marked and observable relaxant effect from Valerian even with the valepotriates removed. Back to the drawing went the marketers to find another angle with which to differentiate their product from the next one on the shelf.
3) Using animal models to research new medicines may not provide useful or relevant data for the use of such medicines in humans. Many chemicals which are found to be harmless to animals are nevertheless toxic to humans. Eg. Thalidomide was extensively tested on guinea pigs before being declared safe for public consumption.
4) Many environmental toxins (pesticides, dioxins etc.) are fat soluble and will tend to concentrate in the lipid components of plant cells. These will be easily dissolved into a solvent (which itself may be a toxin such as hexane, acetone, dichloromethane or benzene) and both exogenous toxins and solvent residues may contaminate the end product. Heating the treated plant material may remove some or most of the solvent residues, but is damaging to the plant cell constituents (eg. Enzymes and proteins are denatured by heat) and will evaporate away any volatile oil fragments which are themselves often highly medicinal.
5) Clinical trials in the classical scientific model are not statistically significant when compared to the hundreds of centuries of empirical knowledge and the experience of clinical practitioners. The traditional healer works with so many sensory and extra sensory perceptions attuned to the differentiating qualities of the patient that no two people will ever receive the exact same treatment protocol. Of course there are similarities and general themes that are frequently incorporated into formulas, and these may form the basis of the modern market for herbal products, but in a professional consultation the details and precise proportions of components in each individual formula are unique each time.
6) Almost all the research being done into single plant ingredients is funded, directly or indirectly, by those with a vested financial interest, a stake, in selling a product. Research endowments to universities, independent laboratories and rainforest research are all being funded by pharmaceutical corporations and they are all looking for a molecule or a process they can patent and thus make money off. Thus the drive toward standardization may be impelled more by a desire to make money than a desire to heal people or to understand herbal medicine.
It is many herbalist's belief that one of the roles of the modern day herbalists is to maintain the simplicity and naturalness of our heritage and to ensure that it always remains readily available to the people. While safety is always of paramount importance, we must be extremely careful to preserve our empirical knowledge of traditional whole plant medicines. The more the natural world is desecrated and destroyed, the more urgent it becomes that the herbalists and traditional healers preserve their cultural heritage and hence their relationship with the Earth.
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