Green chemistry chemical product glyphosate

Glyphosate scientific name N-(o-acyl methyl) glycine, pure white solid, very low water solubility. In fact, glyphosate is a general term for various glyphosate salts. Now there are many varieties of glyphosate in China.From Monsanto to Xinan Chemical, including our country, the evolution of glyphosate products is first ammonium salt, and now a new generation of products is potassium salt.
An important reason why glyphosate in the Chemical Industry has developed so quickly is that conventional herbicides are more harmfuln addition, compared with other herbicides and glyphosate, glyphosate has a better herbicidal effect and relatively lower phytotoxicity.Therefore, it was commercialized in 1974 and became the largest herbicide in 1980.At this time, it was used for weeding in the environment, orchards, or non-planting seasons.    In 1996, the extensive use of glyphosate was greatly promoted by the industrialization of genetically modified crops, and it has now become the largest pesticide species in the world.This is N0.1.
Why is glyphosate a green chemical product?
The characteristics of the mechanism of action of glyphosate are determined by this. The shikimic acid pathway is widely used in higher plants and microorganisms and is the only way to synthesize aromatic amino acids. But there is a lack of shikimate pathways in mammals, fish, birds, reptiles and insects.Glyphosate acts on one of the key enzymes in the shikimic acid pathway: 5-enol** shikimate-3-phosphate synthase (EPSP synthase).  Humans and animals lack this route.    Glyphosate has no target, so it is harmless to humans and animals.
However, this metabolic pathway and this enzyme are very important for plants and microorganisms.Due to this discovery, in particular, after the function of this enzyme was discovered, the herbicide glyphosate was developed.
The next question is, how does glyphosate work on this enzyme?
The EPSP synthase active site binds to the substrates 3-phosphoshikimic acid (S3P) and phosphoenol (PEP), and catalyzes the synthesis of 5-enol** shikimate-3-phosphate (EPSP).    Glyphosate is a structural analog of the substrate PEP. The binding efficiency to the active center of EPSP synthase is much higher than that of PEP. Through competitive binding, it inhibits the activity of EPSP synthase, leading to the death of plants and microorganisms.
The advantage of glyphosate is that it is an excellent herbicide with broad-spectrum virulence and internal absorption conductivity, and it has excellent characteristics such as high efficiency, broad spectrum, low toxicity, low residue, no damage to soil environment, and is the largest herbicide in the world. Variety.Its only drawback is non-selective weed control, which also kills crops.
Why glyphosate is selected for genetically modified organisms, or why the most important species for the industrialization of genetically modified crops is glyphosate-resistant crops?This is also due to its inherent causes.
The first reason is that some soil microorganisms are highly resistant to glyphosate, from which high glyphosate resistant EPSP synthase genes can be obtained. For example, in 1999, we collected glyphosate-contaminated soil and isolated many high-glyphosate-tolerant microorganisms, and then cloned the glyphosate-tolerant EPSP synthase gene. The second reason is the development of transgenic technology that can transfer genes of interest from microbes to crops to obtain glyphosate-tolerant transgenic crops.

The widespread application of herbicide-resistant crops has brought about tremendous agricultural transformation and yield increase benefits.    Some people say that there is no increase in the yield of genetically modified plants.In fact, planting herbicide-resistant crops will increase production. Since 1996, soybean production in the United States with narrow-row spacing has increased by 35%.There is also no-tillage.    This technology has been used to increase production by 35% in the United States and by 57% in Argentina.In addition, as a breeding marker, it is also possible to rapidly cultivate more excellent varieties.