Are All Garlic Products Created Equal?
To understand how and why a garlic product could be effective and useful, you need some basic information. You also need to understand the many differnet “marketing terms” garlic product manufactures use to mis-direct you from the only thing you need to know about their product -
“HOW MUCH ALLICIN DOES IT ACTUALLY CONTAIN?”
The manufactures are quite fond of the phrase “Allicin Potential” – which means simply what might be produced IF everything was perfect. In the real world and in our bodies (where the Allicin will be created under the right conditions) – their “potential” is usually less than 1% of “what could be”. All this means is that what you THINK you are getting from your garlic product is NOT what is actually being delivered by them.
To understand the why and how, read through these sections:
- A Brief History Lesson
- A Brief Chemistry Lesson
- What Is Allicin and What Are Its Medicinal Benefits
- Garlic Supplements the Good the Bad and the Ugly
- New Discovery Creates Powerful Garlic Supplement
- Let’s Wrap It All Up
|A Brief History Lesson
A History of Garlic, the Source of Allicin
To appreciate the importance of allicin it is first useful to appreciate the historical significance of garlic.
Of all the plants used in cooking and natural medicine, it must be the best known and most widely used. This is not surprising given that its reputation as an all-healing herb has been solidly established over thousands of years.
The use of garlic, the plant that is the source of the versatile ingredient and valuable, restorative medicine, dates from Egyptian times. It was also popular with the Babylonians and the Hebrews.
The great pyramid at Giza in Egypt bears an inscription indicating how much garlic and onion was consumed by the workers who built the pyramids. Indeed, it is reported that garlic was the cause of the first known industrial strike, caused when the ruling Egyptians stopped the daily ration of garlic given to the construction teams to ward off disease and build their strength. The men immediately downed tools and refused to continue their labours until rations were restored!
The Egyptians often left clay models of garlic in ordinary graves. However its powers seem to have been acknowledged at all levels of society for, during Howard Carters 1922 excavations, six are fully positioned bulbs were found in Tutankhamens tomb probably to ward off evil spirits. Clearly the Egyptians were familiar with the power of garlic.
According to records, they were renowned for growing large tonnages of grain from which enormous amounts of bread were baked the staple part of an average diet in those days. Unfortunately, this could often lead to problems with tooth decay. Milled flour often contained grains of silica from the sandstone mill wheels and this frequently led to premature wear of the enamel and tooth decay.
The only remedy was to use the pungent qualities of garlic, ground to a paste, and apply it straight to the aching tooth! This rather hot climate was also infested with mosquitoes and other biting insects, many of which carried malaria and other infectious diseases.
Once again it was garlic that came to the rescue as an effective insect repellent.
Garlic has been established as a medicine for thousands of years and was well recognised by the Egyptians, Babylonians, Ancient Greeks, Chinese, Vikings, Indians and Romans.
As time moved on, the uses of garlic in medicine flourished and many great physicians and philosophers made reference to its benefits. Hippocrates, Homer, Aristotle, Pliny, Galen, Virgil and ohammed all believed garlic to have many useful properties.
The Greek and Roman armies were, like the Egyptian workers, fed garlic to build strength, and the first Olympian athletes consumed vast quantities before competitions to build stamina and keep themselves free from illness. It was thought to be food fit for a god or goddess, and was placed ceremoniously on piles of stones at rossroads for the Greek goddess Hecate.
Ever since, garlic has been used by the dominant cultures around the world. Nowhere more so than in China, where garlic has always been used in both cooking and medicine. The Chinese call garlic suan. The fact that this is written as a single sign in such an ancient language indicates a very early cultural recognition.
Traditionally, the Chinese used garlic as an aid to long life as it was known both as a healing and a heating herb, which helped the circulation and was believed to be beneficial in cases of tumours, tuberculosis, coughs, colds, infections and wound healing.
The Romans introduced garlic to Britain and it was later to be grown in monastery gardens. By the Middle Ages, garlic was well established although not necessarily loved by all! It was around this time that legends emerged about its magical properties and renowned ability to ward off evil spirits, in particular vampires!
The long pointed leaves are thought to have given rise to the name gar, meaning spear or lance in Old English and leac meaning leek or potherb or vegetable. The natural origins of garlic lie in the steppes of Central Asia, where the plant grows wild. Other wild varieties grow around the world, usually in wooded areas.
A member of the lily family (Liliaceae) garlics botanical name is Allium Sativum (the cultivated variety). Other close members of the family include the onion (Allium Cepa), chives (Allium schoenoprasum), the leek (Allium porrum) and the shallot (Allium ascolonium). More distantly related are the autumn crocus, bluebell, aloe vera and lily of the valley. Of all the alliums, garlic is the most potent and best known for its culinary benefits and numerous medical uses.
Also commonly grown in Elizabethan country gardens during the 16th century, garlic became known as peasants food. In those days the odour was considered offensive and was not greatly beloved of the middle and upper classes. At about this time, garlic acquired the country name of Poor Mans Treacle, which came from a Greek word for antidote, which in Latin was theiracus. It was also commonly known as Devils Posy and Witch Poison, doubtless due to its reputation for fighting off evil.
Another name that became synonymous with garlic was camphor of the poor, after its strong odour. More recently, two world wars saw attitudes move greatly in garlics favour.
During the First World War, the British Government offered farmers throughout the UK a shilling a pound to grow the plant. This was because its medicinal properties were being used to fight off dysentery and as an aid to healing and the prevention of bacterial infection in wounded soldiers.
In the Second World War garlic was again used extensively for its antibiotic qualities.
|A Brief Chemistry Lesson
SO WHAT IS ALLICIN?
In the opaque terminology of the biochemist, allicin is described as diallyl thiosulphinate, allyl sulphide or even S-(2-Propenyl) 2-propene-1-sulphinothioate.
What is more important to recognise is the most crucial and reactive part of the allicin molecule the sulphur-sulphur bond coupled to an atom of oxygen.
Chemists know that this configuration is highly reactive, giving allicin its remarkable antibiotic properties and, in particular, the potential to assist the immune system in a number of important ways, including stimulating immune cells, killing pathogens and detoxifying carcinogens.
Before the advent of pharmaceutical antibiotics, crushed aqueous garlic extracts were used to treat a wide range of infectious disease, including dysentery, typhoid, cholera, smallpox and tuberculosis.
Then, in the 1930s, the first class of antibiotic drugs was invented the sulphonamides. The reason they were so successful was the presence of the reactive sulphur group exactly the same group that allicin contains.
HOW DOES ALLICIN WORK?
Because allicin is so keen, in biochemical terms, to react with micro-organisms, it is able to penetrate their cell walls. In doing so it is then able to upset their biochemical balance and impede their activity.
At low concentrations of allicin, the degree of interference may not be lethal, but sufficient to block the microbes virulence.
At slightly higher concentrations, the effect can prove lethal for the micro-organism (see later for more details).
|What Is Allicin and What Are Its Medicinal Benefits?
Garlic is remarkable for the number of compounds it contains, including seventeen amino acids, at least 33 sulphur compounds, eight minerals (germanium, calcium, copper, iron, potassium, agnesium, selenium and zinc) and the vitamins A, B1 and C.
It also comprises fibre and water but not a single trace of allicin, the wonder compound that this book is about. How can this be? Its a story of how a plant has evolved to protect itself from attack by microbes in the soil, and heres how it goes:
ALLIIN AND ALLINASE THE DYNAMIC DUO
In 1944 an Italian chemist, C. J. Cavallito, first isolated an unstable, odorous sulphur-containing compound with antibacterial properties from extracts of fresh garlic. He called the substance allicin (al-e-sin), after the generic name for the plant Allium Sativum. Four years later researchers Stoll and Seebeck, also working with garlic, discovered an odourless sulphur-containing compound called alliin (al-e-een). This they found to be converted by a second garlic constituent, an enzyme called allinase (al-i-naze), to form allicin.
The researchers made an additional, remarkable discovery: When they studied the cloves in cross-section they found that alliin and allinase were stored in different compartments. In an undamaged clove they remained completely separate, but once its structure was ruptured typically by cutting the two substances came into contact and formed allicin.
ALLICIN AND ITS MEDICINAL
This transformation is extremely rapid, taking mere seconds. Even more intriguing is the instability of allicin. It remains active only for a short period before degrading.
There must be a reason for this. Nothing in nature exists without a reason. All the clues suggest that garlic possesses a defence mechanism against attack from the soil-borne organisms.
It has been found that invasion of growing garlic cloves by fungi and other soil pathogens causes the alliin and allinase to react, rapidly producing localised bursts of allicin which deactivates the invaders. This ability underlies the exceptional capacity of allicin to kill unwanted organisms, about which you will read more later.
There is a good reason why the highly reactive allicin molecules have such a short working life. If they didn’t they would continue to react with surrounding proteins, including the allinase enzyme itself, and this would use-up the garlics protection, which it might need later.
This extremely efficient binary chemical mechanism ensures that the cloves defence is highly localised and short-lived just sufficient to repel an attack. The remaining alliin and allinase are held in reserve to fight off any subsequent attacks.
While this is good for the wellbeing of a garlic crop, it poses distinct problems for anyone trying to extract and isolate the key active ingredient in a way that is beneficial.
It was five decades after its initial discovery that allicin would be isolated in a stabilised form for the first time.
MOTHER AND OFFSPRING
When allicin degrades, as many as 200 other sulphur compounds are formed.
Many of these, like allicin, are transitory in nature while others endure. One is a compound named ajoene (ah-ho-ene) after ajo, the Spanish for garlic, which has been shown to possess antithrombotic, antimycotic (it kills fungal infections) and anti-fatdepositing actions.
Others that have attracted scientific interest across a wide spectrum of disease conditions have only been used in experiments on animals or on human cell models in the laboratory. These include diallyldisulphide (DADS) and diallltrisulphide (DATS).
Thus allicin can be regarded as the mother substance from which all others flow. Raw garlic degrades into allicin to a greater or lesser extent and then many sons and daughters of allicin form, some of which have beneficial effects on the body and some which do not.
|Garlic Suppliments the good the bad and the ugly!
Do conventional garlic supplements work?
A quite bewildering array of garlic supplements are on offer when visiting a health-food shop or drug store, all apparently offering you allicin. However, in a review of garlic supplement brands carried out in March 2003, the independent consumer body
ConsumerLabs.com found that the strength of these products, judged on each products ability to generate allicin in a laboratory test, varies by as much as 1500 per cent. ConsumerLabs.com found that almost a quarter of non-aged products (aged garlic never produces any allicin) yielded less allicin than was generally considered therapeutic and then only in a laboratory and not in your body, which is an altogether different setting.
The global consumption of garlic per year is approximately 1 clove for every living person! In the UK alone more than two million packs of garlic supplements were purchased in 2005/2006 from chemists, supermarkets and mass-merchandisers to treat elevated cholesterol, hypertension and other common disorders. This makes garlic the most popular herbal product according to many sources.
Yet NONE of those consumers are getting what they actually need from a garlic product that all-important heal-all, allicin.
Why? As weve seen, allicin is created when a garlic clove is ruptured, by the action of two constituents in a defence against attacking soil organisms. But just as allicin is produced in a matter of seconds, its potency dies away with equal rapidity. In its natural, unstabilised form, it rapidly degrades and is simply not available as an active substance for the benefit of humans.
In short, without allicin in its stabilised form, these supplements have little, and mostly no allicin potential. This is confirmed by the total lack of any clinical evidence for any activity as an antimicrobial agent. Consider the ConsumerLabs.com study in a little more detail.
Thirteen non-aged garlic products and one aged product were purchased and tested. The amount of allicin produced by the non-aged garlic products ranged by a factor of 15-fold in the laboratory dish, which bears no relation to the environment of the human body.
There is clearly no consistency of quality. Ironically, a product with one of the lowest allicin yields per gram of garlic claimed to be allicin rich. Several products produced nowhere near the amount of allicin the manufacturer claimed. Few products clearly state their allicin yield and, when they do, they are not always accurate.
The important word in these statements is yield. This is purely a theoretical amount and in the human body this just does not happen. The reason why is that our gastric acids deactivate allinase, the allicin-producing enzyme.
It is estimated by garlic experts such as Dr Larry Lawson and Professor Eric Block, as well as my own research group, that every time you swallow a typical garlic powder product, 95 per cent of it will never become active and you will get virtually nothing from it. Check exactly how much garlic is contained in your supplement, as some are virtually garlic-free. Ask if the product has any published clinical evidence.
A recent paper in the Journal of Agricultural Food Science by Lawson and Wang showed that most garlic supplements are standardised on allicin potential and are enteric-coated to prevent the action of gastric acid. To determine whether these products release the claimed amount of allicin under simulated gastrointestinal conditions (found in your gut), a standard method for drug release was applied to all 24 known brands of enteric-coated tablets.
While all brands employed effective coatings and met their claims for allicin potential when crushed and suspended in water, 83 per cent of them released less than 15 per cent of their potential dissolution allicin release. Only when tablets had high allinase activity and disintegrated rapidly did they show high allicin release
. Crucially the researchers concluded that garlic powder supplements should no longer be standardised on allicin potential, but rather on dissolution allicin release. Further evidence was published in the same journal by two researchers from The Department of Chemistry at the University of California. T
hey analysed a large number of commercially available garlic products and concluded that the amount of allicin available from these products, when analysed in gastric or intestinal fluid, was less than one part per million (ppm). This compares with the guaranteed 100 per cent yield of at least 250ppm allicin from the true allicin-containing products that are now coming to market.
Independent research confirms that many garlic supplements cannot provide ANY of the garlics active principal, allicin. What all this boils down to is that there really is no comparison between the general body of allicin-claiming products and the allicincontaining products that are now being introduced to consumers worldwide.
Some garlic powder tablet preparations do have the ability to generate tiny quantities of allicin, and therefore all the beneficial sulphur compounds that come from allicin will also be present. But, as we have seen, the actual amount of allicin your body receives from these products is minute.
This is why there is absolutely NO DATA published on these products to show any anti-microbial activity, and even recent studies on cardiovascular activity have failed to confirm the promise that early studies showed.
What about raw garlic?
Eating raw garlic, which itself varies quite widely in its relative yield of allicin, is hardly an option, given the social consequences and more technically, the deactivating effect of stomach acid on the allinase. In any case scientists have found that the amount of allicin released from different garlics around the world can vary by as much as 10 times, and given that the best yield is about a 4% allicin yield, youd have to munch an awful lot of garlic!
Or garlic oil?
Results of independent analysis from the Camden Food and Drink Research Association and the prestigious Warren Springs Laboratory show that garlic oil does not provide allicin. This is because it is destroyed by the boiling process used in the oils manufacture.
However, it is fair to say that some oil-based products do contain potentially beneficial sulphur compounds due to high levels of concentration and they may help various circulatory disorders.
Oil or water?
The method of extracting active sulphur chemicals from garlic is particularly important. Extraction using an oil seals up the activity of the sulphur compounds so that they will not readily be available to the body. Consequently, any activity is severely diminished.
Water-based extracts (like real allicin) are MUCH more active. This is the main reason why we see such good results against bacterial infections from allicin and ALL the other active thiosulphinate substances that allicin breaks down into.
Products of water-based extraction methods are able to kill bacteria even when they are diluted 20-30 times more than oil based extracts. So if you want to produce an extract from fresh garlic that actually works microbiologically, you have to use water as an extraction medium. The maximum amount of allicin is created. Whats more, the allicin is removed from the reaction so it wont interfere with the continuing action of the allinase enzyme. Finally, to prove its effectiveness, every batch of allicin produced is microbiologically tested against a multi-drug-resistant strain of bacteria.
Clearly the mainstream garlic extracts are simply not in the same league as the allicin-containing products now on offer. With the advent of new technology, one can now produce and stabilise allicin the heart of garlic.
This means that for the first time ever, anywhere in the world, we have the mother substance from fresh ga
rlic ready to prevent and treat a wide range of common ailments.
COMPARISON OF GARLIC PRODUCTS
|New Discovery Creates powerful Garlic Supplement by Dr Peter Josling, Ph.D.
Naturally Kill Viruses, Bacteria, and Fungus
For over 100 years researchers have been trying to remove allicin from fresh garlic and stabilize it. Fresh garlic contains no allicin, just the two chemicals that combine to form it.
Every cell in a head of garlic contains a tiny amount of allicin and the garlic’s core contains a massive amount of an enzyme called allinase. When a pathogen such as a virus, bacteria, or fungus invades garlic, these two chemicals break open from their exclusive cells and come together to form allicin.
Allicin is only produced when garlic is cut, crushed, boiled, or processed in any way. That begins a chemical reaction that releases the two chemicals that come together and produce allicin.
We know from research going back 50 to 60 years that allicin is a potent antimicrobial agent. It can kill bacteria, viruses, and fungal cells very easily and only a very little is needed to kill invading pathogens. As the two chemicals come together to form allicin, the enzyme dies away quite quickly because it knows it has produced tiny amounts of allicin, but it is enough to kill off whatever has invaded the garlic.
Humans can activate allicin by crushing, chopping, cooking, or otherwise processing garlic. however, most cooking methods break open only a small percentage of the garlic’s cells and produce only a small amount of allicin. Additionally, allicin is incredibly unstable and begins changing into other sulfur chemicals almost immediately.
The challenge lies in the ability to not only release large amounts of allicin from each clove of garlic, but also to capture the allicin and prevent it from decaying into other chemical compounds. Normally, in fresh garlic, when you cook or chop or crush it, you can crush several million cells, but not every single cell. So the amount of alliin you release to convert to allicin is about one-half percent to up to four percent with an efficient processor.
Most garlic supplements on the market today do not actually contain allicin, They contain alliin and allinase and allow the stomach to release the two enzymes found in the supplement and combine to form allicin. However, the hydrochloric acid in the stomach almost immediately destroys the alliin, preventing any allicin from forming.
These other supplements (such as capsules and garlic oil) do contain significant amounts of sulfur by-products of garlic which have been shown to reduce cholesterol and blood pressure by thinning the blood and allowing it to circulate more efficiently through the body. However, none of these products contain the anti-microbial benefits produced only by allicin.
I have discovered a patented method that uses temperature and pressure to release as much allicin as possible. The allicin is then flushed out of the production chamber with water, enabling the allinase to continue to react with allicin. With this process, we can convert up to 97 percent of a garlic bulb’s alliin into allicin.
As we dilute the allicin with water, we end up with a concentration that is mostly water but contains a stabilized solution of allicin that is easy to freeze dry and further process into a powder or gel. The powder and gel physically contain allicin – not alliin or allinase that need to be combined to produce it.
A single capsule of stabilized allicin is the equivalent of 40 heads of garlic.
Allicin is not only a powerful anti-microbial, it also gets into the blood-stream and naturally degrades to form other sulfur chemicals that provide garlic’s heart-healthy benefits.
For the first time in the world, a garlic extract has been actually proven to contain real allicin. The body doesn’t need to make it because it’s already there in powder or gel form. The allicin are biologically active and able to kill viruses, fungi, and bacteria in laboratory studies.
Over the last five to six years, we’ve done controlled clinical trials and case studies on patients who have been infected with viruses or bacterial or fungal infections and have proven that the stabilized allicin is ideal for killing all these microbes and pathogens that cause disease and illness. It’s quite unique in terms of its capability.
You wouldn’t expect any other garlic product anywhere in the world to do the same as stabilized allicin. We don’t use any organic solvents or alcohol. All we use is deionized water to aid in the stabilization process.
When you swallow other garlic powders, capsules and tablest, the allinaise enzyme is destroyed by the hydrochloric acid in the stomach. Without the enzyme, you can’t produce any allicin, another reason the garlic powder and oil products cannot kill any pathogens in the body.
Evidence shows that stabilized allicin in power or gel form can kill the MRSA bacteria (methicillin resistant staphlyococcus aureus), a pernicious bacterial infection that was once only common in hospitals or care homes, but in the last five years has spread to other places where large populations of people congregate such as schools, prisons, and sports venues. This new, community-acquired strain of MRSA has proven difficult to kill, and few prescribed medications are able to do so. However, stabilized allicin is very effective at kill this pernicious bacterial infection. We now have the opportunity for a safe, natural, treatment to treat one of the worst bacterial infections known to microbiologists worldwide. Our discovery of allicin’s effectiveness on the MRSA bacterial began some years ago when we first stabilized the allicin and needed to test it.
We looked at clinical databases on garlic and were suprised to find that there wasn’t a double-blind, placebo-controlled study on the effectiveness of garlic on the common cold. Since on average every single American suffers two to five colds per year, and school children suffer five to ten colds per year, we wanted to test garlic’s ability to prevent and treat the common cold.
Evidence showed the statistically significant differences between the number of actual cases of the common cold found in the stabilized allicin group and the placebo group. There were statistically significant differences between the number of days the infection lasted in each group.
The placebo group’s infections lasted, on average, over five days, while the stabilized allicin group’s infection lasted an average of 1.5 days. This peer reviewed, medically published paper showed that repeat infections were much less likely in the allicin group than in the placebo group.
This widely publish study was the gold standard and was the first to prove garlic’s effectiveness at curing and preventing the common cold. My Colleague, Dr. Ron Cutler, the principal clinical microbiologist at the University of East London, was impressed with the findings and, in 2009, wanted to test stabilized allicin in liquid and powder form in the lab against MRSA.
He assigned one of his doctoral students to grow MRSA bacteria on two petri dishes and test the effectiveness of both the powder and the gel on killing the MRSA bacteria. The student dug a well in the middle of each dish according to FDA-Approved procedure. She then placed the allicin in the wells, and left the dishes for 24 hours.
The next day, the plates were compleetly clean. There was nothing at all. Dr. Cutler accused his student of failing to grow any MRSA in the first place, but she swore that she had completed the test correctly. He then instructed her to regrow the MRSA on new plates and this time dilute the allicin solution by half in each dish. The next day, to our amazement, there were huge zones of inhibition in each plate, meaning that even the highly diluted allicin had dilled an enormous amount of MRSA bacteria.
Dr. Cutler called this a “Eureka moment,” for a universally safe, natural product had been discovered to combat the pathogens as powerful as MRSA. Dr. Cutler published his first clinical paper on treating MRSA with allicin in 2004. Every year since then we’ve published and presented papers at international microbiology meeting all over the world to show that stabilized allicin can kill MRSA infection.
In a recent case study, allicin in gel (topical) or power (oral) form was able to cure all 52 patients infected with MRSA in a period of four to twelve weeks. Most of these patients had open wounds infected with MRSA, in which cases the topical application of allicin was completely effective. After the initial treatment period, the patients were swabbed and tested and every single one was completely free of MRSA.
The case study was eventually expanded to include over 200 patients, all of whom benefited significantly from stabilized allicin. We recently published our findins from this case study in the European Journal of Nutraceutical Research. Ginger synergizes with allicin to increase its effectiveness in the human body. It also adds its own anti-viral capability and has been shown to increase joint mobility too.
The vast majority of people can benefit from taking a regular dose of this formulation – ALLIGIN. Dr. Peter Josling – B.S.C., Ph.D
|Let’s Wrap It All UP
Alligin the only real choice for a garlic product!
It is clear that the only really useful and viable type of a garlic extract is one that contains active “allicin” in a stabilized form. While there can be some small benefit to other garlic products potentially, most will never bring any real benefit to the consumer and they are mostly throwing away their money on them.
Look again at the forms of garlic commononly available that most purchase over the counter in our local stores -
COMPARISON OF GARLIC PRODUCTS
Raw garlic can work, but to combat any “serious” problem necessitates consuming huge quantities of raw garlic, something few would be able to do – having a stabilized, concentrated, bio-active product that can be taken easily at need is the best possible solution. “The powder and gel physically contain allicin – not alliin or allinase that need to be combined to produce it.
A single capsule of stabilized allicin is the equivalent of 40 heads of garlic.”
Alligin is such a product and is now available for everyone to have in their home today.
THE MICROBIOLOGY OF STABILISED ALLICIN
There are four main characteristics that determine how effective an antibiotic will be. Allicin is known as Natures antibiotic and recent work has shown that stabilised allicin has all the required characteristics to make a modern antibiotic capable of killing even the most drug-resistant species of bacteria, including MRSA, MDRTB and PRSP.
The four key characteristics are:
Selectivity - Clinically effective antimicrobial agents all exhibit selective toxicity toward the bacterium rather than the host. It is this characteristic that distinguishes antibiotics from isinfectants. The basis for selectivity will vary depending on the particular antibiotic. When selectivity is high the antibiotics are normally not toxic. However, even highly selective antibiotics can have side-effects.
Therapeutic Index - The therapeutic index is defined as the ratio of the dose toxic to the host to the effective therapeutic dose. The higher the therapeutic index the better the antibiotic.
Categories of Antibiotics - Antibiotics are categorized as bactericidal if they kill the susceptible bacteria or bacteriostatic if they reversibly inhibit the growth of bacteria. In general the use of bactericidal antibiotics is preferred but many factors may dictate the use of a bacteriostatic antibiotic. When a bacteriostatic antibiotic is used, the duration of therapy must be sufficient to allow cellular and humoral defence mechanisms to eradicate the bacteria. If, possible bactericidal antibiotics should be used to treat infections of the endocardium or the meninges. Host defences are relatively ineffective in these sites and the dangers imposed by such infections require prompt eradication of the organisms.
Antibiotic Susceptibility Testing - The basic quantitative measures of the in vitro activity of antibiotics are the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC).
The MIC is the lowest concentration of the antibiotic that results in inhibition of visible growth (i.e. colonies on a plate or turbidity in broth culture) under standard conditions. The MBC is the lowest concentration of the antibiotic that kills 99.9% of the original inoculum in a given time.
For an antibiotic to be effective, the MIC or MBC must be able to be achieved at the site of the infection. The pharmacological absorption and distribution of the antibiotic will influence the dose, route and frequency of administration of the antibiotic in order to achieve an effective dose at the site of infection.
In clinical laboratories a more common test for antibiotic susceptibility is a disk diffusion test. In this test, the bacterial isolate is inoculated uniformly onto the surface of an agar plate. A filter disk impregnated with a standard amount of an antibiotic is applied to the surface of the plate and the antibiotic is allowed to diffuse into the adjacent medium. The result is a gradient of antibiotic surrounding the disk. Following incubation, a bacterial lawn appears on the plate. Zones of inhibition of bacterial growth may be present around the antibiotic disk. The size of the zone of inhibition is dependent on the diffusion rate of the antibiotic, the degree of sensitivity of the microorganism, and the growth rate of the bacterium. The zone of inhibition in the disk diffusion test is inversely related to the MIC.
The test is performed under standardized conditions and standard zones of inhibition have been established for each antibiotic. If the zone of inhibition is equal to or greater than the standard, the organism is considered to be sensitive to the antibiotic. If the zone of inhibition is less than the standard, the organism is considered to be resistant.
Combination Therapy - Combination therapy with two or more antibiotics is used in special cases: (1) to prevent the emergence of resistant strains, (2) to treat emergency cases during the period when an etiological diagnosis is still in progress, and (3) to take advantage of antibiotic synergism. Antibiotic synergism occurs when the effects of a combination of antibiotics is greater than the sum of the effects of the individual antibiotics. Antibiotic antagonism occurs when one antibiotic, usually the one with the least effect, interferes with the effects of another antibiotic.
Information from “Nature’s Powerhouse Healers” by Dr. Peter Josling – Copyright by HRC Publications – All Rights Reserved