[Ninong]

Originally Posted by charlesr1958

It is only fair to the fish to use known cures and avoid voodoo medicine until alot more is known about it.

I agree that little is known about the effects of garlic on C. irritans but I do not agree that garlic should be classified as "voodoo medicine."

A few years back Horge wrote a nice article on the possible benefits to be obtained by feeding garlic. He pointed out that the active ingredient in garlic is allicin. He also mentioned that freshly minced garlic cloves would be more effective than garlic extract or commercially available chopped or crushed garlic in a jar. I believe he said that this was because of the short "shelf life" of allicin, if I remember correctly. He also pointed out that the fish would have to consume a large quantity of the garlic to ingest a sufficient dosage of allicin to be therapeutically significant.

Anyway, a couple of years after reading that article, I successfully fought off an outbreak of ich in my aquarium by feeding the fish freshly minced garlic twice a day for about five or six weeks straight. I used fresh garlic cloves that I chopped over and over again until they were practically mush. My ich was imported on a Coral Beauty Angelfish (Centropyge bispinosa) that I thought was ich-free when I purchased it. Since I had only five relatively small fish in my aquarium at the time, I fed only about 1/4 tsp of finely minced garlic twice a day.

Since then I have done additional research on garlic to see if I could find anything to explain it's effect. I was about to say to support Horge's claims but he didn't actually make any claims as such. In fact, he was careful to point out that no scientific research had been conducted on the effects of garlic on Cryptocaryon irritans. If it is effective -- and I believe that it sometimes is -- we don't know for sure why it is effective. Does it interfere with the parasite's ability to locate the host fish? Does eating garlic make the host fish "unattractive" to the parasite? Does eating garlic cause the parasite to disengage from the host fish prior to maturity? Does consumption of garlic by the host fish somehow affect the parasite's ability to successfully complete it's life cycle?

We know for a fact that garlic has some beneficial applications in human medicine because it has been researched extensively. A review of some of those applications led me to discover that the biologically active allicin molecule is created when the garlic is crushed or minced. Alliin is the name given to the amino acid that is present in large quantities in garlic cloves. Alliin is the stable precursor to allicin. Alliin is transformed into allicin when garlic is crushed. The enzyme responsible for this transformation is allinase, which is present in garlic cloves in large amounts (10% of the total protein content -- 10mg/g fresh weight). This transformation takes place within a matter of seconds. There are some commercial processes that transform allicin into a stable powder or extract but I think that best results for our purposes are obtained by feeding freshly minced (crushed) garlic to the fish. My fish seemed to think it was a special treat. I was surprised that they actually ate it. Again, I think it is better to prepare the minced garlic yourself from fresh garlic cloves just before each feeding.

Here is some additional background that I copied from the medical literature. I didn't copy any of the charts or graphs and I left out the current laboratory studies but I think it will give you some good food for thought. A review of this literature has led me to believe that it is quite possible that freshly minced garlic could have as yet unexplained beneficial results when fed to fish.

Garlic cloves are odor-free until crushed or processed when garlic supplements are manufactured and cross-section studies have indicated that the substrate alliin and the enzyme allinase are located in different compartments. This unique organization suggests that it is designed as a potential defense mechanism against microbial pathogens in the soil. Invasion of the cloves by fungi and other soil pathogens causes the interaction between alliin and allinase that rapidly produces allicin and which in turn inactivates the invader. The reactive allicin molecules produced have a very short half-life, as they react with many of the surrounding proteins, including the allinase enzyme, making it into a quasi-suicidal enzyme.

This very efficient organization ensures that the clove defense mechanism is only activated in a very small location and for a short period of time, whereas the rest of the alliin and allinase remain preserved in their respective compartments and are available for interaction in case of subsequent microbial attacks.

Successful clinical use of garlic for treating elevated blood pressure and arteriosclerosis has been known since the early part of this century. It has been reported that regular garlic intake causes both a prolonged lowering of hypertension and an improved sense of well-being in patients. As early as 1928, definite blood pressure decreases were achieved as well as increases in productive heart power with garlic therapy, not only in older patients, but also in younger hypertonic patients.

It is also well established that garlic extracts, in particular the powders can show a significant anti-cholesterol activity. A 12 week study comparing the effect of standardised garlic powder tablets (900mg daily) with that of bezafibrate (600mg daily), one of the most commonly prescribed blood lipid-lowering drugs until the advent of the statins, has also been conducted. The multi-centre, double-blind study was performed with 94 patients having cholesterol and/or triglyceride vales exceeding 250mg/dL. After 4 weeks of treatment, the decreases in cholesterol, LDL cholesterol, and triglyceride levels were all statistically highly significant, and there were no differences between the effects of garlic and bezafibrate. HDL cholesterol values in the course of 4 weeks also increased significantly, again without any differences between the two regimens.

The antibacterial properties of crushed garlic have been known for a long time. Various garlic preparations have been shown to exhibit a wide spectrum of antibacterial activity against Gram-negative and Gram-positive bacteria including species of Escherichia, Salmonella, Staphylococcus, Streptococcus, Klebsiella, Proteus, Bacillus, and C!ostridium. Even acid-fast bacteria such as Mycobacterium tuberculosis are sensitive to garlic. Garlic extracts are also effective against Helicobacter pylori the cause of gastric ulcers. Garlic extracts can also prevent the formation of Staphylococcus enterotoxins A, B, and C1 and also thermonuclease. Cavalito and Bailey were the first to demonstrate that the antibacterial action of garlic is mainly due to allicin. The sensitivity of various bacterial and clinical isolates to pure preparations of allicin is very significant. The antibacterial effect of allicin is of a broad spectrum. In most cases the 50% lethal dose concentrations were somewhat higher than those required for some of the newer antibiotics. Interestingly, various bacterial strains resistant to antibiotics such as methicillin resistant Staphylococcus aureus as well as other multidrug-resistant enterotoxicogenic strains of Escherichia coli, Enterococcus, Shigella dysenteriae, S. flexneni, and S. sonnei cells were all found to be sensitive to allicin.

Most recently the University of East London have shown that aqueous extracts of allicin when formulated into a simple cream are able to kill vast swathes of the so called "superbug" MRSA (methicillin resistant Staphylococcus aureus). This nasty bacterium is forever changing its structure and developing resistance to many pharmaceutical antibiotics. This may have a significant effect on people who suffer from skin diseases such as eczema and acne as this bacterium is 6 to 7 times more likely to colonise these patients.

There is a growing body of evidence that garlic may have significant enhancing effects on the immune system. While most of the work has been conducted on animals or in vitro, the human studies that have been conducted are encouraging.

Preliminary studies in humans, using an alliin standardised garlic powder preparation, have demonstrated positive effects on immunoreactions and phagocytosis. In geriatric subjects, the administration of 600mg garlic powder per day for 3 months induced significant (p<0.01) increases in the percentage of phagocytosing peripheral granulocytes and monocytes when tested ex vivo for their ability to engulf Escherichia coli bacteria. The cell counts of lymphocyte cell sub-populations were also increased. Another human study was conducted with an unrefined garlic extract (5-10 g/day) which was given to AIDS patients. For the seven patients who completed the 12-week study, there was a major increase in the percent natural killer cell activity from a seriously low mean value of 5+-4% to a more normal mean value of 36+-15%.

The biological activity of allicin extracted from fresh garlic is thought to be related to a combination of factors:

1. its activity as an antioxidant

2. its ability to attack the sulphur (SH) groups in enzymes and proteins and modify their activities and

3. its ability to rapidly penetrate into cells through the cell membranes.

Allicin has a number of beneficial properties, which could act together to enhance the bodies response to disease. Published laboratory studies have found that allicin:

>Enhances the activity of phagocytic cells

>Enhances the activity of natural killer cells

>Inhibits the growth of pathogenic micro-organisms

>Inhibits the growth of certain cancer cells

One of the main problems with laboratory studies has been the purity of the extracts used, only recently has a purified, natural, stable extract of allicin become available for testing. Recent studies in our own laboratory have confirmed the antibacterial activity of this purified allicin extract against a number of different bacteria including multiply antibiotic resistant Staphylococcus aureus (MRSA). Clinical trials with this substance are currently underway.