Unfortunately, in everyday vocabulary the word chemistry has a pejorative undertone.
This chemophobia applied to the case of food makes one of the most feared words is that of herbicide.
Any farmer who uses it to protect his crops from weeds (flora arvense in ecologically correct vocabulary) is considered little short of a poisoner.
Its use in the urban environment to take care of roads, parks and gardens has also been very limited by some municipalities.
However, trying to judge chemistry as "good" or "bad" is nothing more than making subjective value judgments on objective scientific topics. Each molecule is determined by its atoms and how they are linked, and its usefulness will depend on how we use it. The important thing is that there is a regulation that regulates its use in safe conditions, and thus we do not have to deprive ourselves of scientific advances that can make life easier. There are numerous molecules that would make this fallacious discourse questionable and no one would be able to classify them as good or bad, or in any case they would be both at the same time.
A good example is nitisona. In 1977 the chemist Reed Gray, working for the multinational Zeneca (now AstraZeneca), discovered that around an Australian plant called red broom or brush tree (
Callistemon citrinus
) hardly grew herbs. Investigating this fact, he discovered some alkaloids that the plants of this family produced that were toxic to other plants. In this way, the tricetonic herbicides were synthesized, which when applied to the lawn caused it to turn whitish and finally dry out. The mechanism of action is based on the fact that when absorbed by the plant it inhibits the synthesis of carotenoids, which are the molecules responsible for the characteristic color of carrots and whose function is to protect chlorophyll from excessive solar radiation. If there are no carotenoids, the chlorophyll breaks down, the grass turns whitish and dies. When applied to mice, small doses during toxicity tests increased the levels of certain amino acids in urine. At high doses the animal died poisoned by accumulation of this amino acid.There are some genetic diseases, type II tyrosinemias, in which those affected have the same symptoms as mice treated with nitisone. Later research discovered that this molecule inhibited an enzyme in the degradation pathway of an amino acid called tyrosine, and, as happens in these cases, the accumulation of this amino acid together with some degradation products produces toxic effects in animals and plants.the accumulation of this amino acid together with some degradation products produces toxic effects in animals and plants.the accumulation of this amino acid together with some degradation products produces toxic effects in animals and plants.
However, everything has its utility. When it was described how nitisone worked, it was of great interest to Lindstedt and Holme, two researchers at the University of Gothenburg in Sweden, who were studying metabolic diseases related to the breakdown of tyrosine. There is a very serious type I tyrosinemia in which a defect in an enzyme in the tyrosine breakdown pathway causes a molecule that is very toxic to the liver to accumulate. The only possible treatment was liver transplantation, usually in childhood, and life expectancy was very low because the toxic molecule continued to accumulate after transplantation. However, nitisone inhibited this same degradation route, but in a previous step, so the toxic product did not accumulate, but another one that was easy to metabolize by the body.The first clinical trial was conducted in a two-month-old infant, and then they were confirmed in four more patients with spectacular results. Nitisone has been licensed as a type I tyrosinemia drug since 2002. And this is how, thanks to the use of small doses of this herbicide, sorry, miracle drug, along with a diet that limits tyrosine levels, many children suffering from a serious illness can lead a normal life and avoid a liver transplant that could only extend your life a few years. So is nitisone good or bad? Is it a herbicide or a drug?Thanks to the use of small doses of this herbicide, sorry, miracle drug, together with a diet that limits tyrosine levels, many children suffering from a serious illness can lead a normal life and avoid a liver transplant that could only lengthen their lives. some years. So is nitisone good or bad? Is it a herbicide or a drug?Thanks to the use of small doses of this herbicide, sorry, miracle drug, together with a diet that limits tyrosine levels, many children suffering from a serious illness can lead a normal life and avoid a liver transplant that could only lengthen their lives. some years. So is nitisone good or bad? Is it a herbicide or a drug?
Mustard gas for leukemia
There are many examples of molecules with a use that have been successfully applied in other fields. Most drugs of natural origin have a hormonal or defense function against insects in the plants from which they are obtained and, on the other hand, in our body they can help alleviate the symptoms of some diseases, such as salicylic acid, a hormone plant that inhibits an inflammatory pathway in humans. A more surprising case is that of mustard gas. Thanks to an attack by the Nazis in World War II on an American ship loaded with this gas docked in the port of Bari, it was seen that it mainly affected the bone marrow and the immune system of those affected was loaded ..., and that's how One of the first effective treatments for leukemia was discovered, which consisted of treating patients with a chemical weapon.
JM Mulet is Professor of Biotechnology.