Nagase Viita : Research and Development Story / Achieving mass production through speedy R&DGlycosylated Vitamin C 'ascorbic acid 2-glucoside'

Vitamin C (Ascorbic Acid) is an essential nutrient for humans and is known for its role in inhibiting melanin production and strengthening the immune system. However, Vitamin C is chemically unstable and sensitive to heat and light, making it difficult to use in products.
If Vitamin C, which is stable and not easily broken, could be produced industrially, it would find more applications in various fields, including food and cosmetics. Ascorbic Acid 2-Glucoside is the answer to these expectations. Let's follow the story behind the mass production of an innovative and stable form of Vitamin C.

A novel substance brought from academia

Structure of Ascorbic Acid 2-Glucoside
Ascorbic Acid 2-Glucoside is made by binding one molecule of glucose to the hydroxyl group at the C-2 position of the Vitamin C (Ascorbic Acid) using an enzymatic reaction, thereby increasing its stability. This compound is formed using a technique called "glycosylation", in which a sugar is bound to other substances through enzymatic reaction.
Nagase Viita (formerly Hayashibara Co., Ltd.) has been researching and commercializing this technology for a long time, and products such as "COUPLING SUGAR" a starch syrup (glycosylsucrose syrup) produced by binding glucose or maltooligosaccharides to sucrose were already on the market.

Ascorbic Acid 2-Glucoside was first introduced to the world through the research of Professor Itaru Yamamoto at the Faculty of Pharmaceutical Sciences, Okayama University (see the column at the bottom). In 1989, Professor Yamamoto discovered that the Vitamin C glycoside produced by an enzyme derived from rats was Ascorbic Acid 2-Glucoside, a new Vitamin C glycoside with properties different from those of previously known Vitamin C glycosides. The amount obtained from the reaction with the rat enzyme was so small and it was insufficient for further analysis. Therefore, Professor Yamamoto contacted us to see if we could find an enzyme that can work more efficiently, producing a large amount of Ascorbic Acid 2-Glucoside.

In the university laboratory, the obtained quantity is very small so that a breakthrough was needed to establish a method for efficient mass production. Hajime Aga, then an up-and-coming young researcher in his fourth year with us, was singled out as a technical expert to meet this challenging request.

CGTase, the enzyme that paved the way for mass production of Ascorbic Acid 2-Glucoside

Aga first investigated an analytical method that could clearly distinguish Ascorbic Acid 2-glucoside from other Vitamin C glycosides with similar structures. By connecting the state-of-the-art detector "Photodiode Array" at that time to the conventional detector "HPLC", it became possible to clearly distinguish Ascorbic Acid 2-Glucoside from other Vitamin C glycosides, enabling more accurate analysis.

Next, to find enzymes with higher production efficiency, about 20 of different enzymes were selected from our numerous laboratory stocks that potentially involved in the glycosylation. Vitamin C and transferable sugars were placed in a series of test tubes and allowed to react with the selected enzymes, and then their products were analyzed.

The results showed that Ascorbic Acid 2-Glucoside was produced by several enzymes, in particular, cyclomaltodextrin glucanotransferase (CGTase) was found to be extremely efficient in its production. In fact, this CGTase had been routinely used internally by us for the production of “COUPLING SUGAR” and other products.
Compared to the enzyme derived from rats, the microbial CGTase is highly efficient producing Ascorbic Acid 2-Glucoside, and is easily procured in-house. Aga’s proper selection of enzymes led to a success to mass production in just a few days.

Ascorbic Acid
2-Glucoside crystals

Manufacturing facilities developed in the 1990’s

The research team that Aga belongs to immediately began trial production using this CGTase enzyme. After only a month and a half, 4.1kg of Ascorbic Acid 2-Glucoside with a purity of 96% was produced. Then a month later, in August 1989, we succeeded in precipitating Ascorbic Acid 2-Glucoside crystals for the first time in the world. This success made possible to achieve high-purity, easy-to-handle product specifications.

Manufacturing facilities developed in the 1990’s

Once the research team established the method for producing Ascorbic Acid 2-Glucoside, the production department began development for industrial mass production. One of the research team members, who was familiar with the method, joined the production department to establish the manufacturing method and also to develop manufacturing equipment incorporating the new technology. This series of initiatives was made possible only because we have an integrated system from research and development (R&D) to manufacturing.
In 1995, the long-awaited Vitamin C derivative with excellent stability was released to the market from Hayashibara Co., Ltd. (Nagase Viita at present.)
This achievement was highly acclaimed, and in 2020, we received the
"Planning, Technology, and Activities Award" from the Vitamin Society of Japan
(the world's only society specializing in Vitamins with a history of over 70 years)

Continuous research efforts develop a value to the world

Hayashibara Biochemical Laboratories., Inc. Amase Institute (1990’s)

No matter how excellent the properties of a new substance are, if it can be produced only in a small test tube, it will never be beyond the realm of research. The value of such a substance can be delivered to the world and contributed to society only when a stable mass production is established at a realistic cost.

The development for mass production of Ascorbic Acid 2-Glucoside was accomplished at an amazing speed of three months by only four members of Nagase Viita research team. This achievement can be attributed to the fact that we have been researching enzymes for many years.

First of all, our laboratory had a wide range of inventory of enzymes, so it was a great advantage that the researchers were able to start the experiment right away. Also, the fact that the production department had routinely handled large amounts of CGTase, allowed us to use an abundance of the enzyme, which would have been usually difficult for research laboratories to procure, and led to the early establishment of the production method for Ascorbic Acid 2-Glucoside.
The accumulated knowledge through the manufacturing of reagents over many years also contributed to the making of several kilograms of prototypes and development of purification methods for Ascorbic Acid 2-Glucoside. By utilizing the limited manufacturing facility and trying possible method one after another, the production department was able to get the desired results quickly. Needless to say, the research team, led by Aga, had indispensable knowledge about enzymes as a foundation of the project.

Researcher Hajime Aga

The newly acquired technology at the time was later utilized in the development of trehalose mass production.

Researcher Hajime Aga

Researcher Aga recalls that time.

"At that time, I was just taking the same process as in my usual research, making hypotheses, preparing samples, and repeating experiments. Many of the predictions happened to be right on target and the results were good, so we were happy with each stage. If my predictions turned out wrong, I would just come up with a different method and try again and again. Looking back, I realized I had accomplished something amazing through continuous effort."

Functional material with low environmental impact

Ascorbic Acid 2-Glucoside has been used in many personal care products in Japan and overseas as a material with effects such as inhibition of melanin production since it was launched as a cosmetic material "AA2G" in 1995.
Before then, when formulating Vitamin C in brightening cosmetics, it was necessary to add antioxidants together to prevent the tendency of Vitamin C to be degraded by heat and light, or to add Vitamin C in large amounts by predicting its decomposition. Ascorbic Acid 2-Glucoside solved these problems and made it possible to develop more functional products at a lower cost.

The raw materials of Ascorbic Acid 2-Glucoside are simple: Vitamin C, enzymes, and starch. Since the natural function of enzymes is utilized in the production process, the energy load in the manufacturing process is low. Furthermore, the waste discharged during the manufacturing process is reduced by recycling the nutrition rich byproduct as feed for livestock.

Our products, which rely on the action of microbial enzymes, are highly evaluated not only in terms of functionality but also in terms of sustainable development and manufacturing, and are drawing attention globally, especially in Europe and the United States, where environmental awareness has been high in recent years. We will deliver value and continue to expand our business globally.


Invention by Professor Itaru Yamamoto,

Ascorbic Acid 2-Glucoside was invented in 1989 by Professor Yamamoto, at the Faculty of Pharmaceutical Sciences, Okayama University.

In his research on the physiological effects of Vitamin C inside the body, Professor Yamamoto focused his attention on Vitamin C glycosides. He thought that Vitamin C ingested from food could be glycosylated by enzymes within the animal body and stored as a stable-derivative molecule.
Therefore, an enzyme found from rat intestine (α-glucosidase) was reacted with Vitamin C and sugars to produce glycosides (sugar-added compounds). When the product was analyzed by HPLC, it was found that the detection time was slightly different from that of Ascorbic Acid 6-Glucoside (Vitamin C glycoside made by an enzyme from black mold, with reducing property), which had already been discovered. The differences detected were extremely small, but Professor Yamamoto's observation led to identify this compound as a novel Vitamin C glycoside.

Later research showed that this Ascorbic Acid 2-Glucoside is not oxidized even when exposed to air, and when entered into the body, it reacts with enzymes present in the body and breaks down into Vitamin C and glucose.
  • The compound discovered by Professor Yamamoto of
  • Okayama University has been successfully mass-produced
  • by Nagase Viita located in the same prefecture, Okayama.
  • This was a great accomplishment of local industry-academia
  • collaboration.
  • The compound discovered by Professor
  • Yamamoto of Okayama University
  • has been successfully
  • mass-produced by Nagase Viita in
  • Okayama. This was a great
  • accomplishment of local industry-academia
  • collaboration.