• Wed. Jan 19th, 2022

How Vitamin C (Ascorbic Acid) is made industrially (Reichstein Process)

Vitamin C also known as Ella sorbic acid vitamin C is a vitamin commonly found in foods such as vegetables or citrus fruits vitamin C was first made in 1933 and between the 18th to the 20th century it was used to treat and prevent a disease known as scurvy currently vitamin C has a wide range of industrial applications the main ones being pharmaceuticals which accounts for 50% food additives 25% beverages 15% and animal feed 10% between 2014 and 2015 vitamin C saw a global market revenue of about 820 million u.s. dollars and is expected to increase.

Due to demand in terms of production more than 100 kilo ns of vitamin C was produced where 80 percent came from plants in China by manufacturers such as DSM or North East pharmaceutical group one of the common methods for vitamin C production is known as the two-step fermentation process and like most modern methods it is a variation of a historical process known as the Reich Stein process with glucose as the starting material it can mimic the biosynthetic pathway in plants and animals and allows for stereo selective synthesis.

So how does the Reich Stein process work starting with D glucose the aldehyde group indeed glucose needs to be reduced to an alcohol to form d sorbitol catalytic hydrogenation with a nickel catalyst is used for this the carbon to hydroxyl group in D sorbitol is selectively oxidized by psorbos dehydrogenase in a  rmentation process this is an important step since the enzyme offers selectivity for the carbon 2 hydroxyl group without the need for protecting groups which forms else or bows the next step is the further oxidation of the carbon one hydroxyl group to a carboxylic acid group which is done by protecting the hydroxyl groups using acetone and an acid media this forms the dye acetone psorbos intermediate oxidation with potassium permanganate followed by the addition of water and acid D protects the hydroxyl groups which reforms acetone and forms two keto al ghul onic acid in the last step the ring is closed by the removal of water to form a lactone ring which is vitamin c tautomerization between the keto enol form can occur the enol form contains the acidic proton of vitamin c where its conjugate base is stabilized by d localization with the ester group for the two-step fermentation process this process differs from the reich stein process in that the el psorbos undergoes a second fermentation step with sorbus on dehydrogenase rather than chemical oxidation this results in the direct formation of two keto al ghul onic acid rather than the die acetone psorbos intermediate overall both processes form vitamin c when comparing the two processes the two-step fermentation process has advantages over the reich stein process the main ones being reduced amounts of poisonous gases produced in a more simple procedure which means less equipment and raw materials needed all of which reduce the overall cost of production.

However both methods gives yields of about 60% current research is ongoing to genetically modify a single organism capable of performing all three steps by looking at vitamin C’s natural biosynthetic pathways recently a single step synthesis by microalgae has been reported but the yields are much lower than the current methods the two-step fermentation process is just one of many ways the rx9 process can be modified to produce vitamin C industrially no matter which process is used vitamin C will always find its way to consumers whether it is in foods beverages or supplements it will always be an essential part of our diets.