Dear all, at first we need to select: what is deactivation? Is it destroying? Or binding? Or we need to know how effective is liver P-450 in vivo against mycotoxins? How can we use binders if these binders can chemically react with vitamins? What is alternative? Grain without mycotoxins: is it possible? Probably not, and this is problem for everybody. Let's discuss!
Vito D’Ascanio Dear Dr. Vito, you are absolutely right. Of course, the theoretical basis for the action of mycotoxin sorbents is better developed than for many other anti-mycotoxin agents. This is not surprising, because the basics of sorption were developed by classical chemistry, and sorption / desorption processes are widely used in industry and agriculture, as well as for scientific purposes, for example, in chromatography. Considering the features of the chemical formula of mycotoxins, we can conclude that in terms of molecular weight, they and vitamins are in very close ranges. However, the quantitative content of mycotoxins in grain is much lower than that of vitamins, and therefore the sorbent (unless, of course, it is chemically modified for some specific mycotoxin) will first absorb the substance whose concentration is higher. Detailed experiments on this issue have not been carried out, because there are a lot of various vitamins and mycotoxins in nature, and buyers are used to using sorbents they have long known, and the price of vitamins, in the total cost of feed, is not so high. Experiments using microorganisms were an alternative to chemical sorbents. The pioneer in these methods was the American company Alltech, which found that yeasts have the ability to absorb many types of mycotoxins by the membrane of their cells. Further research has shown that certain strains of bacteria can break down mycotoxins with the help of specific enzymes. If you are interested in these questions, I could send you photographs obtained in the laboratory of our company, where our specialists managed to select suitable strains. At the same time, we focused on the effect of bacteria, but the mechanism of their destructive action, it seems to me, has not yet been investigated.
Dear Dr. Marchenkov, thanks for your comment. For the binders we are speaking about a binding mechanism. Dietary supplementation with non-nutritive mycotoxin-adsorbents is by far the most practical and most widely studied method for reducing the effects of mycotoxin exposure. Of course, an effective mycotoxin adsorbent should be a nutritionally inert adsorbent, which when incorporated into contaminated feed, should prevent or limit toxin absorption from the gastrointestinal tract of animals, and carryover of mycotoxins into animal products, such as aflatoxin M1 in milk. To study the non-specific binding with important nutrients (such as vitamins), in vitro trials can be performed. These trials are useful select promising binders for further in vivo test. There are different strategies (physical or chemical) to reduce the contamination of mycotoxins in feed, but most of them show different drawbacks with restricted practical applications.
It is surprising that in 2022 we are making questions that were resolved in 1987 /1988
In vitro trials will never prove that a product will work in vivo.
This was proven in 1988 with Activated Charcoal it captured 100% of the mycotoxin in vitro but it did not work in vivo protecting the target organ.
Deactivation - Biotransformation - Adsorption
The best explanation is the rumen of a cow. A rumen can biotransformation and/or deactivate mycotoxin as long as you have perfect conditions
When stress, acidosis, use of antibiotics, bacterial infections, not well balance feed ocurre this biotransformation / deactivation is reduced significantly. In the case of adsorption the same way that the clay comes in the same way that the clay com out and it is not affected by conditions in the GI tract. The key factor on adsorption is the quality , type and process that is done to the clay so it is capable of adsorbing one and or multiple toxins.
Also you need to differentiate products that reduce the secondary effect caused by a mycotoxin vs product that by adsorbing the mycotoxin are capable of Protecting the Target organ that the mycotoxin affects. This is the only way to differentiate true mycotoxin binders vs hepatoprotections , immunomodulators, probiotics that improve productivity parameters but do not protect the target organs.
Dear Dr. Tamames, thanks for your comment. As I explained and underlined in my talk, one of the drawbacks of the in vitro models is that "no prediction of in vivo results can be ensure". So I agree with you, but I would like to add something more.
Even if in vitro data are not able, so far, to predict in vivo results, they can give us an insight into the mechanism (on the physico-chemical point of view) of binding between toxins (adsorbate) and binders (adsorbent). Using the isotherms approach, the kinetic approach and in vitro gastro-intestinal models, scientists can have an idea about the performances of the binder towards the adsorbate.
These studies are useful to screen and select "potential binders" to be tested in animals. It is unfeasible to test in animals all binders, due to the cost, ethical constraints and management of in vivo trials.
Furthermore, in vitro trials allow the determination of toxic side effects, including the non-specific adsorption of vitamins, minerals, amino acids and so on. In this way you can have an idea about the behaviour of the binder with molecules different from toxins and if any, you can avoid to test in vivo binders with a very low specificity.
Concerning Activated Charcoal, it is well known its ineffectiveness in vivo, but it is also known its specificity in the vitro models; so no practical uses could be expected. For other binders instead, a correlation has been observed between in vitro and in vivo data on efficacy (it is the case of bentonites and aflatoxins).
The main goal is to minimize / avoid mycotoxin effects to consumers, thus we should target/point forward to methods which can achieve this goal. Either prevention from the source or deactivation after contamination. This will involve intense research on, say, deactivators under different environmental conditions to ascertain the effectiveness. This means it should be tested both in vitro and in vivo then we make a choice / choices.
Jonathan Tarus Dear Mr.Jonathan, Your logic is absolutely correct. I want to draw your attention to the fact that until now there have been practically no in vitro studies on the possibility of non-specific sorption of vitamins and other molecules with similar molecular weight contained in feed. There are a lot of conversations, usually ending with the conclusion that this sorption is insignificant. On this occasion, I recommend making a solution of vitamin B2 (riboflavin) in water, add some sorbent to it and mix and look at the change in color of the solution. Well, general considerations are also interesting: for example, to what extent can toxic food be used? What toxicity should the feed have in order to be able to say that it is already pointless to use it, it is better to just throw it away, because there will only be losses on the farm with such feed.
For poultry, I have formulated two mycotoxin binders namely Mycodetox B1 and Mycodetox B2 based on my decade's research on chickens, quails, turkeys and ducks. Both the binders ameliorated the adverse effects of aflatoxicosis in poultry and are equally efficaceous in ameliorating aflatoxicosis in these poultry species.
Dr. Ram Singh Bibyan
Dr. Marchenkov, in relation to your question on binders binding vitamins, please keep in mind that today customers are using maximum of 2 kg per ton of feed toxin binder. I won't recommend anything more than that. At such levels of inclusion, vitamin binding is zero or very minimal. 70% of the global feed today contains one or other mycotoxin binder. Very rarely we get questions from customers on nutrient binding. There was a time when customers were using 5 kg per ton clay binders. Those days are gone. More than nutrient binding, the customers need to evaluate technical dossier of the product related to in vitro or in vivo binding as well as performance benefits. Research has shown significant impact of almost all the mycotoxins on gut and immune systems in animals. We need to make sure the product helps in reinstating these organ systems. Mycotoxin binding concept alone will not help to manage all the mycotoxins we know today. I hope this helps.