What Is Oxaloacetic Acid?
Oxaloacetic acid is a low-molecular-weight biological substance with the chemical formula C4H4O5. It is an organic acid featuring a four-carbon atom chain, two carboxyl groups (COOH), and two carbonyl groups (C=O). It is also known by several names, including α-ketosuccinic acid, 2-ketosuccinic acid, 2-oxosuccinic acid, 2-ketobutanedioic acid, 2-oxobutanedioic acid, OAA, and its former name, oxalacetic acid.
In the citric acid cycle (tricarboxylic acid cycle or TCA cycle), oxaloacetic acid plays a crucial role by reacting with acetyl CoA, leading to the production of citric acid. This cycle is integral for energy generation and metabolite production. Oxaloacetic acid also serves as a necessary intermediate in amino acid metabolism and as a precursor for some amino acids.
Additionally, it is involved in glycogenesis via phosphoenolpyruvate and is the first substance produced in carbonic acid fixation in C4 plants. It is unstable at room temperature, readily converting to pyruvate upon decarboxylation.
| Chemical formula | C4H4O5 |
| English name | Oxaloacetic acid |
| Molecular weight | 132.07 |
| Melting point | 161 °C |
Properties of Oxaloacetic Acid
1. Chemical Properties
Oxaloacetic acid is a dicarboxylic acid containing carboxyl and ketone groups. It is acidic, with a strong acid characteristic and a relatively low pH in aqueous solutions. It is also unstable and can oxidize in air.
2. Biochemical Properties
In the citric acid cycle, oxaloacetic acid is transformed into citric acid. It is produced by amino acid breakdown and can react with amino-containing molecules to form aspartic acid.
3. Biological Role
Oxaloacetic acid plays a vital role in cellular metabolic reactions, particularly in energy production within the citric acid cycle. It is also involved in amino acid and carbohydrate metabolism.
Uses of Oxaloacetic Acid
1. Pharmaceuticals
Oxaloacetic acid is utilized in pharmaceuticals, including hypertension and antiepileptic drugs. It has been studied for its potential in treating liver dysfunction, and kidney disease, and as an antioxidant and anticancer agent.
2. Catalyst for Chemical Reactions
It is used as a catalyst in organic synthesis reactions such as alkylation and acetoacetylation.
3. Food Additive
Oxaloacetic acid is used as a food preservative, believed to be more effective than acetic acid. It also acts as a coagulation promoter for gelatin.
4. Improvement of the Taste of Soft Drinks
It enhances the taste of carbonated and sports drinks, imparting a refreshing flavor.
Other Information on Oxaloacetic Acid
Precautions for Use
Handling oxaloacetic acid requires a safety and health officer experienced with hazardous materials. Refer to the SDS for safety guidelines. In case of accidental contact, wash with water and seek medical attention. Store away from fire and high temperatures in closed containers. Avoid mixing with alkaline substances to prevent heat generation. Never ingest, and avoid excessive inhalation or skin absorption. Dispose of waste appropriately.