Glyphosate (IUPAC name: N-(phosphonomethyl)glycine) is a broad-spectrum systemic herbicide and crop desiccant. It is an organophosphorus compound, specifically a phosphonate, which acts by inhibiting the plant enzyme 5-enolpyruvylshikimate-3-phosphate synthase. It is used to kill weeds, especially annual broadleaf weeds and grasses that compete with crops. Its herbicidal effectiveness was discovered by Monsanto chemist John E. Franz in 1970. Monsanto brought it to market for agricultural use in 1974 under the trade name Roundup. Monsanto's last commercially relevant United States patent expired in 2000.
https://en.wikipedia.org/wiki/Glyphosate
John E. Franz (born December 21, 1929) is an organic chemist who discovered the herbicide glyphosate while working at Monsanto Company in 1970.[1] The chemical became the active ingredient in Roundup, a broad-spectrum, post-emergence herbicide. Franz has earned much acclaim and many rewards for this breakthrough. He also has over 840 patents to his name worldwide.
Discovery of glyphosate[edit]
Researchers at Monsanto had been searching for an herbicide that was effective against annual and perennial weeds for nine years but found little success. They knew of two phosphonic acid compounds that were ineffective against weeds, and the researchers were not able to advance the compounds. Franz took over the research in 1969 and incorrectly hypothesized that the phosphonic acids acted as proherbicides that were metabolized to active compounds rather than herbicides. Franz and his research team screened possible metabolites and synthesized compounds and eventually discovered glyphosate in 1970.[2]
Although all of the patents regarding glyphosate list Franz as the sole inventor and the Monsanto Company as the assignee, Franz acknowledged that the discovery was a group effort. In 2007, when he was inducted into the National Inventor's Hall of Fame, Franz said, "It's a recognition of the entire team of scientists who worked on and supported the development of Roundup herbicides".[5] Glyphosate works by absorption through leaves, and then moving rapidly to a plant's roots, rhizomes, and meristems. This invaluable breakthrough immediately spurred Monsanto to design and produce plants genetically immune to glyphosates in order to make it easier for farmers to thoroughly spray down their fields for weeds without killing their own crops.[6]
Once glyphosate was invented, it took four years to reach the market. It was first introduced as "Roundup", and is still best known by that brand.[2]
Glyphosate has been called by experts in herbicides "virtually ideal" due to its broad spectrum and low toxicity compared with other herbicides.[6][7][8] However, the chemical’s use has come under attack in numerous countries, with bans or partial bans enacted, and thousands of lawsuits filed alleging the chemical is carcinogenic. German Chancellor Angela Merkel stated in June 2019 “We will come to a point where glyphosate isn’t used anymore.” [9]
Other research[edit]
Franz undertook research in many areas during his time at Monsanto. Some of his other chemistry research includes antiauxin chemistry (isothiazoles, isoxazoles, pyrazoles), plant chemistry, cell membrane chemistry (glyceride and phospholipid syntheses, liposomes), plant hormone chemistry (abscissic acid analogs, ethylene generators), and nitride sulfide chemistry. He also performed research pertaining to reaction mechanisms, coenzyme A antimetabolites, biorational design of herbicides, and periselective addition reactions of one- and threedipoles, as well as fundamental organic research.[3]
Honors[edit]
Franz has received many awards for his important discovery. In 1977, he was awarded the IR-100 award by Industrial Research magazine. In 1981, he received the first J.F. Queeny Award from Monsanto to honor an invention that was also a commercial success. He was the recipient of the 1987 National Medal of Technology, one of the few agricultural technologies to ever receive the honor. Franz received the American Chemical Society’s Carothers Award in 1989 for "outstanding contributions and advances in industrial applications of chemistry". In 1990, he was awarded the Perkin Medal by the American Section of the Society of Chemical Industry, based on his contributions to the research and development of applied chemistry. Franz also won the Outstanding Achievement Award in 1988, the 1988 Missouri Award, and was named the St. Louis Metropolitan Bar Association Inventor of the Year in 1986. Roundup was named one of the "Top 10 Products That Changed the Face of Agriculture" by the magazine Farm Chemicals in 1994. Franz was inducted into the United States' Inventor's Hall of Fame on May 5, 2007.[2][10][11]
Monsanto has also created two awards in his honor. On December 8, 1995, the agricultural company introduced the Franz Sustainability Award, which consists of an annual $100,000 prize given to the individual or team that submits the best environmental project for improvement in the areas of conservation, technology, and/or education.[12] Soon after Franz's induction into the Inventors' Hall of Fame in 2007, Monsanto announced a new annual scholarship called the Franz Innovation Award Scholarship. This scholarship is awarded each year to a graduate student taking organic chemistry at the University of Minnesota.[13]
Patents[edit]
Franz has over 840 patents to his name concerning glyphosate and lesser known discoveries. Because of the nature of glyphosate, it requires many patents concerning identification, synthesis, and other processes required to produce the chemical.[14]
His patents include:[15]
- Patent Number: 3799758, Phytotoxicant compositions[1]
- Patent Number: 3853530, Regulating plants with n-phosphonomethylglycine and derivatives thereof[16]
- Patent Number: 3977860, Herbicidal compositions and methods employing esters of[17]
- Patent Number: 3954848, Process for producing N-phosphonomethy glycine[18]
- Patent Number: 4735649, Gametocides[19]
- Patent Number: 4634788, Herbicidal glyphosate oxime derivatives[20]
- Patent Number: 4094661, Plant Growth Regulators[21]
https://en.wikipedia.org/wiki/John_E._Franz
Glyphosate-based herbicides are usually made of a glyphosate salt that is combined with other ingredients that are needed to stabilize the herbicide formula and allow penetration into plants. The glyphosate-based herbicide Roundup was first developed by Monsanto in the 1970s. It is used most heavily on corn, soy, and cotton crops that have been genetically modified to be resistant to the herbicide. Some products include two active ingredients, such as Enlist Duo which includes 2,4-D as well as glyphosate. As of 2010, more than 750 glyphosate products were on the market. The names of inert ingredients used in glyphosate formulations are usually not listed on the product labels.
Glyphosate and glyphosate-based herbicides have low acute toxicity in mammals. They likewise have not been shown to pose a significant risk to human health during normal use, although human deaths have been reported from deliberate ingestion of concentrated RoundUp. It is difficult to determine how much surfactants contribute to the overall toxicity of each formulation. Glyphosate formulations containing the surfactant polyethoxylated tallow amine (POEA) are sometimes used terrestrially, but are not approved for aquatic use in the US due to their toxicity to aquatic organisms.
There have been multiple lawsuits against Monsanto asserting that exposure to glyphosate herbicides is carcinogenic and that the company did not adequately disclose the risk to consumers. In 2018 a California jury awarded $289 million in damages (later cut to $78 million on appeal[1] then reduced to $21 million after another appeal[2]) to a groundskeeper who argued that Monsanto failed to adequately warn consumers of cancer risks posed by the herbicides.[3]
https://en.wikipedia.org/wiki/Glyphosate-based_herbicides
Glufosinate (also known as phosphinothricin and often sold as an ammonium salt) is a naturally occurring broad-spectrum herbicide produced by several species of Streptomyces soil bacteria. Glufosinate is a non-selective, contact herbicide, with some systemic action.[1] Plants may also metabolize bialaphos, another naturally occurring herbicide, directly into glufosinate.[2] The compound irreversibly inhibits glutamine synthetase, an enzyme necessary for the production of glutamine and for ammonia detoxification, giving it antibacterial, antifungal and herbicidal properties. Application of glufosinate to plants leads to reduced glutamine and elevated ammonia levels in tissues, halting photosynthesis and resulting in plant death.[3]
https://en.wikipedia.org/wiki/Glufosinate
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