Erythorbic acid does not have a specific pharmacological target. It functions as an antioxidant by scavenging free radicals and reducing oxidative stress. As an isomer of ascorbic acid, it has similar antioxidant properties but is not a vitamin. It also has antibacterial activity. Its mechanism involves inhibiting oxidation reactions in foods and biological systems.

In vitro, erythorbic acid is a potent antioxidant. It effectively scavenges free radicals. Its antioxidant activity is assessed by measuring its ability to reduce oxidative damage in cell-free systems. It also has antibacterial activity. The compound is used in oxidation assays to evaluate its capacity to protect against lipid peroxidation and other oxidative processes.

In vivo, erythorbic acid is used as a food antioxidant and preservative. It helps to maintain the natural color and flavor of food products while increasing shelf life. It is used as an antioxidant in the brewing industry and as a reducing agent in photography. It is generally recognized as safe (GRAS) for use in foods.

In vitro antioxidant assays for erythorbic acid measure its ability to scavenge free radicals. Common assays include DPPH radical scavenging, ABTS radical scavenging, and ORAC (oxygen radical absorbance capacity) assays. The compound's ability to inhibit lipid peroxidation is measured in liposomal or cell membrane systems. Its antibacterial activity is assessed by determining the minimum inhibitory concentration (MIC) against various bacterial strains.

In vitro cellular studies are conducted using various cell lines to evaluate the antioxidant and cytoprotective effects of erythorbic acid. Cells are treated with erythorbic acid and exposed to oxidative stress inducers (e.g., H2O2). Cell viability is assessed using MTT or other assays. ROS production is measured using fluorescent probes. Lipid peroxidation is assessed by measuring malondialdehyde (MDA) levels.

In vivo animal experiments with erythorbic acid are typically conducted in the context of safety and toxicology studies. Standard OECD guidelines for acute oral toxicity, skin irritation, and eye irritation are followed using rodent models. The compound is administered via oral gavage or dermal application, and animals are monitored for adverse effects. Its safety as a food additive is well-established.

Absorption, Distribution and Excretion
Isoascorbic acid is readily absorbed and metabolized. In human subjects, oral administration of 500 mg of isoascorbic acid resulted in similar upward trends in the concentration curves of both ascorbic acid and isoascorbic acid in the blood. In five human subjects, oral administration of 300 mg of isoascorbic acid had no effect on the excretion of ascorbic acid in urine. In hamsters, rats, and rabbits, L-ascorbic acid is poorly absorbed in the intestines due to its non-essential nature, primarily through passive diffusion; conversely, in guinea pigs and humans, ascorbic acid absorption is mediated by a saturable, sodium-dependent active transport mechanism. Therefore, the first few animal groups are unsuitable as models for human absorption. Because the active transport system is saturable, but passive diffusion can also play a significant role at high dose levels, ascorbic acid absorption is dose-dependent. Isoascorbic acid appears to be another substrate in the same transport system, but its activity is much lower than that of L-ascorbic acid, thus it may act as a weak competitive inhibitor of L-ascorbic acid absorption. In studies using brush border vesicles isolated from guinea pig ileum, K1 values were estimated to be approximately 11 mM and 20 mM; in contrast, the apparent Km value for ascorbic acid absorption in the same system was approximately 0.3 mM. The lack of stronger antiscurvy activity of isoascorbic acid may be due to the fact that tissues cannot retain it as efficiently as they do for storing ascorbic acid. Absorption of isoascorbic acid via the human buccal mucosa was investigated in healthy adult subjects. The absorption of a 10 mM isoascorbic acid solution at pH 6 was 13.0 ± 0.74 μmol/5 min. No statistically significant difference was found in the absorption of isoascorbic acid and L-ascorbic acid. For more complete data on the absorption, distribution, and excretion of isoascorbic acid (13 items in total), please visit the HSDB record page.

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Biological half-life
In dogs, this results in a plasma half-life of approximately 30 minutes for isoascorbic acid.

Erythorbic acid has a molecular formula of C6H8O6 and a molecular weight of 176.12 g/mol. It is a stereoisomer of ascorbic acid (vitamin C). It appears as a white to off-white crystalline powder. It is soluble in water. For storage, it should be kept in a cool, dry place, protected from light and moisture. The compound is supplied with high purity (≥97%).

Interactions
This study investigated the regulatory effects of three antioxidants—sodium L-ascorbate (SA), ascorbic acid (AA), and sodium isoascorbate (SE)—on the two-stage development of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced gastric cancer in F344 rats. Dietary supplementation with 5% SE significantly reduced the incidence of pyloric dysplasia and had a minor effect on the incidence of forestomach papillomas; however, no such effects were observed with the addition of 5% and 1% SA, or 5% AA. These results suggest that SE has a weak inhibitory effect on gastric cancer development. Sodium isoascorbate: Rapid intravenous administration of tetracycline hydrochloride (50 mg/kg) resulted in significant azotemia and other signs of kidney damage in rats and dogs, which were prevented by concurrent administration of ascorbic acid (125 mg/kg or higher). D-isoascorbic acid showed similar effects in rat studies.

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Non-human toxicity values
Oral LD50 in mice: 8.3 g/kg
Oral LD50 in rats: 18.0 g/kg

As a food additive, erythorbic acid is generally recognized as safe (GRAS) and has low toxicity. It can cause mild skin and eye irritation at high concentrations. The oral LD50 in rats is high, indicating low acute toxicity. As a research chemical, standard laboratory safety precautions should be followed when handling it. It is not intended for human therapeutic use.

D-Isoascorbic acid is an ascorbic acid. It has been reported to be found in Hypsizygus marmoreus, Grifola frondosa, and other organisms with relevant data. Therapeutic Uses: Isoascorbic acid is a stereoisomer of L-ascorbic acid and is used as an antioxidant in food and oral pharmaceutical preparations. Its vitamin C activity is approximately 5% that of L-ascorbic acid.
Erythorbic acid is also known as D-(-)-Isoascorbic acid, D-Araboascorbic acid, and D-erythro-Hex-2-enoic acid γ-lactone. It is a stereoisomer of ascorbic acid (vitamin C) with strong antioxidant properties. It is used as a food additive, antibacterial agent, and antioxidant. It is denoted by E number E315. It is widely used as an antioxidant in foods and beverages.

C6H8O6

176.1241

176.032

89-65-6

Sodium erythorbate;6381-77-7

54675810

Off-white to light yellow solid powder

2.0±0.1 g/cm3

552.7±50.0 °C at 760 mmHg

167-172ºC

238.2±23.6 °C

0.0±3.4 mmHg at 25°C

1.711

-2.41

4

6

2

12

232

2

C([C@H]([C@@H]1C(=C(C(=O)O1)O)O)O)O

CIWBSHSKHKDKBQ-DUZGATOHSA-N

InChI=1S/C6H8O6/c7-1-2(8)5-3(9)4(10)6(11)12-5/h2,5,7-10H,1H2/t2-,5-/m1/s1

(2R)-2-[(1R)-1,2-dihydroxyethyl]-3,4-dihydroxy-2H-furan-5-one

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: (1). This product requires protection from light (avoid light exposure) during transportation and storage.  (2). Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~125 mg/mL (~709.74 mM)
H2O : ~83.33 mg/mL (~473.14 mM)

Solubility in Formulation 1: 100 mg/mL (567.79 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication.

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 (Please use freshly prepared in vivo formulations for optimal results.)