Vitamin A: BASF synthesis

Vitamin A: BASF synthesis

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The technical vitamin A synthesis from BASF

Structure of the intermediate stages

At BASF, based on the isoprene condensations in nature, they chose C5Building blocks as the optimal size of synthesis building blocks. On this basis, a method for building the C.20- Framework of vitamin A from a C.15- and a C.5-Part developed:

C.15 + C5 → C20

As C5-Building block was used for the synthesis β-formylcrotyl acetate (C.5Acetate), a compound accessible from acetone.

The synthesis of the C15-Section in the form of the β-ionylidene-ethyl-triphenylphosphonium salt (C.15Salt) is achieved via β-ionone. A Wittig reaction with different C5-Carbonyl compounds various derivatives of vitamin A (retinoids) are synthesized. The most important product from BASF is vitamin A acetate.

With the C15Salt, the synthesis sequence goes through a well-crystallizing intermediate stage. This opens up the possibility of removing any impurities that may have been carried over from the preliminary stages at this point. This advantage is all the more important as the purification of β-ionone itself is only possible with considerable effort and loss through distillation.

Since the β-ionone was still obtained as a natural product at that time and was therefore not available in sufficient quantities and at acceptable conditions, a new, economical synthesis method had to be developed to provide this important intermediate.

Vitamin A: BASF synthesis - chemistry and physics

Ludwigshafen, Germany, January 10, 2018 - BASF has set up a website,, to inform its customers, stakeholders from the industry and the interested public about the progress of the repair work on its citral production plant in Ludwigshafen inform. A fire broke out in the facility on October 31, 2017. For this reason, BASF had to declare force majeure for all citral and isoprenol-based fragrances and flavors, for vitamins A and E and for some carotenoid products. The website also provides up-to-date assessments of product availability after the plant has been restarted.

Citral plant in Ludwigshafen: BASF provides information on the progress of the repair work on a new website

  • Regularly updated information also on product availability after commissioning

Ludwigshafen, Germany, January 10, 2018 - BASF has set up a website,[1], to keep its customers, industry stakeholders and the interested public informed about the progress of the repair work on its citral production plant to inform in Ludwigshafen. A fire broke out in the facility on October 31, 2017. For this reason, BASF had to declare force majeure for all citral and isoprenol-based fragrances and flavors, for vitamins A and E and for some carotenoid products. The website also provides up-to-date assessments of product availability after the plant has been restarted.

As things stand today, BASF confirms that the citral plant cannot be put back into operation until March 2018 at the earliest. Starting up the plant is expected to take several weeks. Subsequent products will be manufactured gradually after citral production has resumed.

Product availability estimates
Fragrances and Flavors: The availability of derived products from BASF's Fragrances and Flavors division will vary depending on the product. For around 80% of the portfolio, volume production will begin within the first four to eight weeks after the citral factory is commissioned. The other products (for example acetates) will be manufactured as soon as possible.

Human nutrition, animal nutrition and cosmetic ingredients: The vitamin A and vitamin E plants in Ludwigshafen can only be put back into operation once the supply of citral has been restored and the corresponding intermediate products for the production of vitamins A and E are available. Follow-up products from the BASF human and animal nutrition businesses as well as cosmetic ingredients (vitamin A, vitamin E, several carotenoids) from the Ludwigshafen site are expected to be released for shipping or transport six to twelve weeks after the citral factory has been restarted. The actual availability is heavily dependent on the product.

The guide time for the transport of the products varies depending on the region. It is a few days or weeks within Europe and several weeks or months for overseas shipping. Within the scope of its contractual obligations and in accordance with applicable law, BASF currently supplies its customers fairly and appropriately with the stocks that are still available from the time before the fire on October 31, 2017.

"We sincerely regret that this force majeure has put many of our customers in a very difficult position," said Melanie Maas-Brunner, head of BASF's Nutrition & Health division. “I assure you that the commissioning of the citral production plant in Ludwigshafen has the highest priority. At the same time, we want to keep our customers and stakeholders continuously informed about the progress of our activities. "

Customers who require specific information that is not available on the new website, please contact their sales representative.

Vitamin A: BASF synthesis - chemistry and physics

On October 31, there was a fire when starting up the citral plant in Ludwigshafen. For this reason, BASF had to shut down the plant and declare force majeure for all flavor ingredients based on citral and isoprenol.

BASF declares force majeure for vitamins A and E and several carotenoids

  • Citral plant shut down after fire
  • Downstream systems cannot be restarted after being shut down as planned

On October 31, there was a fire when starting up the citral plant in Ludwigshafen. For this reason, BASF had to shut down the plant and declare force majeure for all flavor ingredients based on citral and isoprenol.

The plants for vitamins A and E are also currently shut down due to scheduled maintenance work. The company will not be able to restart these plants until supplies of citral have been restored and the corresponding intermediates for vitamins A and E are available.

Since the clean-up work, the subsequent inspection, repair and recommissioning of the citral plant will take several weeks, BASF now has to extend the force majeure to vitamins A and E and, as a result, to several carotenoid products.

The consequences of force majeure for companies and customers are currently being assessed. At the same time, BASF is implementing measures to limit the impact of the incident.

BASF will continuously inform its customers about further developments and details on the delivery capacities of the affected products.

Vitamin A: BASF synthesis - chemistry and physics

BASF has started expanding the vitamin A production complex at the Ludwigshafen site. The new building expands the existing vitamin A plant, which went into operation in 1970. A total of around 600 machines and apparatus, 4,000 pipelines and.

BASF is lifting the force majeure for the products Lutavit®A1000, Lutavit®A500, Vitamin A Palmitate 1.6 million I.U./g, Lutavit®E50, Lutavit®E50 S and Vitamin E Acetate 94% in the Animal Nutrition Business Unit. The lifting of the force majeure for other vitamin products as well as several affected ones.

A research team at the Leibniz Institute for Catalysis (LIKAT) in Rostock has developed a new catalyst based on cobalt. This enables the production of benzylamines, an important synthetic step especially for the production of pharmaceuticals. The catalyst is working.

(dpa-AFX) The chemical company BASF cannot start up the production of vitamins A and E again for the time being because of a fire at the end of October. BASF said that the company would only be able to put the corresponding plants back into operation once the supply of the precursor citral has been restored.

Physicists measure the physical properties of vitamins

In quantum physics, unobserved particles spread out like extended waves in space. This phenomenon is philosophically exciting and of technological relevance: A research team at the University of Vienna led by Markus Arndt was able to show that the combination of.

Contribution to a better understanding of complex metabolic processes

Chemists at the University of Leipzig have created an artificial, boron-containing vitamin B 1 that can contribute to a better understanding of the complex metabolic processes in all living things. Like the gears of a clockwork, innumerable processes are intertwined in the metabolism. Around .

It's sweet, rich in vitamins, and is considered to be a mood-enhancer. The mango is often referred to as the queen of exotic fruits because of its aromatic taste, popularity and distant origin. As with other fruits, pesticides are often used in mango cultivation.

Capacity expansion for vitamin A by 1,500 tons per year

BASF has started planning the construction of a new vitamin A complex in Ludwigshafen. The new plant will increase BASF's annual production capacity for vitamin A by 1,500 tons. The reference value for this is vitamin A acetate with 2.8 million international units. With the .

Production capacity for vitamin A in Ludwigshafen increased by 25%

BASF increases its production capacity for VitaminA by 25%. The company has expanded the plant in Ludwigshafen, which is part of its citral network. With this capacity expansion, BASF is responding to the increasing demand for its high-quality vitamin A products and to the.

With immediate effect and worldwide, BASF is increasing the price of vitamin B2 for animal and human nutrition. The prices for vitamin B2 products increase by 20%. Existing contractual agreements with our customers are not affected by this.

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Vitamin A: BASF synthesis - chemistry and physics

In this edition of the podcast, you can hear how fortifying foods with vitamin A prevents children from going blind.

According to UNICEF, 40 to 60 percent of children and adolescents in developing countries are affected by vitamin A deficiency. This makes it the most widespread form of malnutrition. Microencapsulated vitamin A makes it possible to fortify staple foods with vitamin A and thus combat the problem.

Since April 2007, BASF Corporate Communications has started a regular bilingual podcast offering in an easily understandable, informative and entertaining way to report on BASF innovations and research and development activities.

In this issue with the experts Dr. Andreas Blüthner (Global Coordinator BASF Micronutrient Initiatives) and Dr. Lutz End (Research Department & quotFormulation Technologies Nutrition & quot at BASF)

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BASF is the world's leading chemical company: The Chemical Company. The portfolio ranges from oil and gas to chemicals, plastics and performance products to pesticides and fine chemicals. As a reliable partner, BASF helps its customers to be more successful in almost all industries. With high-quality products and intelligent solutions, BASF helps to find answers to global challenges such as climate protection, energy efficiency, nutrition and mobility. BASF employs more than 95,000 people and posted sales of almost € 58 billion in 2007. BASF is listed in Frankfurt (BAS), London (BFA) and Zurich (AN). Further information on BASF is available on the Internet at

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Vitamin A: BASF synthesis - chemistry and physics

BASF: Fine for price fixing? Image: dpa

Because of price fixing for vitamin B-4, BASF and other European chemical companies have to reckon with a cartel penalty - that can be up to ten percent of annual sales.

T he European Commission will, according to information from people familiar with the situation, impose antitrust penalties on European chemical companies for fixing the price of a certain vitamin.
The companies involved in the cartel included the German BASF, the Dutch Akzo Nobel and the Belgian UCB.

The Commission will act accordingly at its meeting on Thursday. The companies involved in the price cartel also included three non-European companies. The EU Commission can impose cartel fines on companies of up to ten percent of the respective annual turnover.

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Use as an additive in animal feed

The Commission's cartel watchdogs found out that the companies had negotiated prices for vitamin B-4, which is used, for example, as an additive in animal feed, it said. The vitamin is also known under the chemical name Choline Chloride. In June of last year, a US federal court fined the Japanese Mitsui and three other companies for fixing the price of the chemical with fines of $ 147 million.

At BASF in Ludwigshafen, a spokesman said the investigation was related to price fixing for vitamins, which became public in 1999. "The Choline Chloride investigation was separated from the rest of the investigation at the time for reasons unknown to us," he said. "We worked with the authorities and submitted all the requested documentation," he added.

Heavy fines in the 1990s

Vitamin producers such as Roche, BASF and Aventis were fined heavily in Europe and the USA for illegal price fixing for vitamins in the 1990s. In addition, lawsuits totaling more than one billion dollars were settled with settlements in the United States. At Akzo Nobel, a company spokesman said the company had not been contacted by the commission about any antitrust penalties.

The BASF share closed on Tuesday in computer trading Xetra barely changed at 52.38 euros.

Influence of different levels of vitamin E doses in fattening pigs on meat and bacon quality depending on storage

99 individually kept, fattening pigs (castrated males) were divided into 3 groups. 33 animals each were supplemented with 0, 0.5 or 1.0 g of α-tocopheryl acetate per day last 21 days before slaughtering.

Samples from blood, liver, bacon, and muscle were taken to determine vitamin E content by HPLC depending on the time of storing. TBARS values ​​of muscle and bacon, induction-time of bacon (“Rancimat”), pH, drip loss, and color of muscle were determined as further criterions of quality.

The vitamin E supply increased significantly the vitamin E content of all samples (eg, serum: 1.5, 2.4, and 2.7 mg / kg liver: 3.8, 5.6, and 7.0 mg / kg for 0, 0.5, or 1.0 g per animal per day , respectively). Vitamin E content of pork decreased depending on time of storing (3.9, 6.2, and 7.8 mg / kg vers. 1.9, 4.1, and 5.0 mg / kg after 29 weeks of freeze storing). Storing time had no significant influence on vitamin E content of bacon.

Vitamin E supply (esp. 1.0 g daily) decreased TBARS values, increased time of induction and improved meat color, but did not influence pH and drip loss of pork significantly.

Why do apples turn brown?

Have you ever made a fruit salad? If so, then you should be familiar with this phenomenon. Making a fruit salad is very easy: You cut different fruit into small pieces and mix everything in a bowl. But have you ever noticed that after a while the fruit, especially apples, turn brown and look like they're rusting? In this experiment you will be shown how and why some fruits turn brown and how you can prevent it!

What you need for it

Cutting boards, apples, fruit knife, lemon squeezer, bowls, three plates, a lemon, vitamin C powder and a spoon

Instructions for the experiment

Cut the lemon in half and use the lemon squeezer to squeeze out the juice. You then pour the juice into a bowl. Then you cut the apples into wedges. Put the first apple wedge on the first plate, untreated.

You place the second column in the bowl with lemon juice and roll it in it so that the surface is evenly in contact with lemon juice. You then place this column on the second plate. Sprinkle the third apple wedge evenly with the vitamin C powder and place it on the third plate. Make a note of which apple wedge is on which plate.

Now you wait a few minutes and you can already see results. You would have to observe that the first apple slice is already starting to turn brownish. In contrast, the other two columns with the lemon juice and the vitamin C powder have remained light and still look very fresh!

Why is this happening?

Plants such as apples contain certain substances that are also called phenols. There are also certain enzymes called phenol oxidases. These enzymes do not normally come into contact with the phenols because they are spatially separated from one another in the cells. However, if we cut an apple into wedges, we destroy the cells, whereby the phenol oxidases come into contact with the phenols. The phenol oxidases oxidize the phenols when they come into contact with the air, i.e. oxygen. The phenols then react to form quinones. These quinones are polymerized to melanins after a while. Polymerizing means that the individual quinone molecules are connected to one another, so that a very large molecule is created. The melanin is a pigment and ensures the brown color. Lemon juice and the powder contain vitamin C. Vitamin C is scientifically also called ascorbic acid and is an antioxidant. The ascorbic acid ensures that the reverse reaction of quinones to phenols takes place. So if you put vitamin C on the apples, it prevents the formation of melanin and thus also the brown color.

How do you still know the formation of melanin?

We humans and animals also form melanins. They occur in our skin, in our hair and in our irises in the eye. When we are exposed to the sun, melanin protects us from the damage caused by UV rays by converting the absorbed energy, which is harmful to us, into heat energy in a flash. In addition, the formation of melanin in our skin is promoted when exposed to sunlight. That's why we get tan in summer when the sun is shining.

Forerunner for vitamin A in rice

The shortage of vitamin A in food causes health problems worldwide that can lead to blindness or even death. In emerging and third world countries, children are particularly affected who, due to malnutrition, do not consume enough vitamin A or its precursor beta-carotene.

Carotenoids also ensure the distinctive color of the eponymous carrots or sweet potatoes, which is why beta-carotene is often used by the food industry as food coloring E160 for the color design of soft drinks, yoghurts and other foods. Rice, the most important staple food in Asia, lacks beta-carotene in grain, but there are carotenoids in the leaves. The plant uses these long, fat-soluble pigments in photosynthesis, which generates energy and oxygen, but also for other processes.

One of the first precursors of beta-carotene is the still colorless phytoene, which is located in the lipid bilayer of plastid organelles - i.e. in the outer shell of these closed cell areas that are involved in photosynthesis, among other things - and is not soluble in water is. It is reworked by the enzyme phytoene desaturase (PDS) into the next, already yellowish, synthesis stage.

Freiburg researchers from the working groups of Prof. Dr. Peter Beyer at the Faculty of Biology and Prof. Dr. Oliver Einsle at the Faculty of Chemistry and Pharmacy has now succeeded in elucidating the three-dimensional structure of phytoene desaturase from rice and thus the mechanism of phytoene conversion.

To do this, Dr. Sandra Gemmecker and Anton Brausemann isolate and crystallize the enzyme with high purity in order to obtain a three-dimensional structure image through diffraction experiments with X-rays. They found that PDS is partially immersed in the lipid bilayer of the plastid organelles and a water-repellent channel points into the interior of the enzyme. In a first step, the phytoene molecule finds its way to the reaction center of the enzyme via this channel, where half of the phytoene is converted to the next carotenoid intermediate.

After the intermediate product has left the channel again in the same way, it enters another, directly adjacent PDS enzyme and is completely converted there. The enzyme is regenerated by a helper molecule, a so-called quinone, which is introduced into the same channel, absorbs excess electrons and thus prepares the enzyme for the next round of conversion.

If PDS does not work properly in a plant, for example due to interaction with a pesticide, the seedlings of the plant no longer look green, but pale whitish and the plant dies after a few days. Scientists around the world have been looking for ever more precise mechanisms of carotene synthesis in plant extracts since the early 20th century, but the search turned out to be difficult because of the complicated composition of various enzyme complexes and their relatively small number in the plant cells.

The Freiburg scientists succeeded in elucidating the structure of the enzyme PDS with a special feature: At the reactive center there was a molecule of the pesticide norflurazon, which was developed in the 1970s and which was added during the PDS isolation. The presence of norflurazon deactivates PDS and is no longer available for the growing plant, which leads to the bleaching of the plant and its death. The position and orientation of this bleaching herbicide inside the enzyme can thus provide future researchers with the basis for new crop protection products to control weeds. In addition, it is now possible to bring about specific changes in the sequence of the enzyme in order to use green genetic engineering to give a crop an advantage over weeds.

The chemical properties of lemon juice

Lemon juice is a versatile substance that is used in hair care and baking to household cleaning. Lemon juice can lighten hair and sour milk, and cure sore throats. It is a common household staple and a component of many products, be it because of its chemical properties or simply because of its fresh smell.
Low pH

One of the most important chemical properties of lemon juice is its low pH. With a strongly acidic pH of 2, lemon juice is just below gastric acid on the pH scale. The high acidity of lemon juice means that it contains a high concentration of hydrogen ions. Like other acidic substances, lemon juice is acidic and can attack metals. Its caustic properties make it a useful ingredient in cleaning products as it softens the minerals in hard water and makes the detergents work more effectively.
Vitamin C source

Lemon juice is high in vitamin C. Lemons contain about twice as much vitamin C as oranges on average. Doctors first discovered this trait of lemons in the 17th century when they discovered that consuming lemon juice daily could prevent outbreaks of scurvy. However, the high levels of vitamin C in lemon juice are lost if the juice is left exposed to the air for long periods of time.
Antimicrobial properties

Research has shown that lemon juice also has certain antimicrobial properties. Studies suggest that lemon juice can stop Aspergillus mold from growing, and lemon juice has been used to disinfect drinking water and inactivate the rabies virus. This property of lemon juice appears to be tied to its citric acid content, which can break down bacterial cell membranes

Vitamin A hypervitaminosis

Vitamin A hypervitaminosisAcute or chronic overdose of vitamin A. Acute poisoning occurs after ingestion of 150000-300000 IU of vitamin A, e.g. in the case of researchers in the Arctic through genus of polar bear or seal liver. There is an increase in intracranial pressure (pressure in the brain) with headache, vomiting, apathy or excitation and subsequent peeling of the skin. No deadly cases are known. Chronic poisoning results from the daily intake of around 20,000 IU in small children or around 100,000 IU in adults over months (e.g. regular consumption of beef liver). Symptoms are dry, rough skin and inflammation of the lips, later also headache (pseudotumor cerebri) and general weakness. After stopping the vitamin A supply, the symptoms subside in 1-4 weeks.

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