What Is a Creatine?
Creatine is an odorless, white, crystalline powder.
Its chemical formula is C4H9N3O2, molecular weight is 131.13, and its CAS number is 57-00-1, it is also called 2-(1-Methylguanidino)acetic Acid. Creatine occurs naturally in the human body, with more than 90% found in muscle and some in the brain.
The body’s total creatine stores are estimated to be about 120 g for an adult weighing 70 kg. Creatine is synthesized in the body from three amino acids (arginine, glycine, and methionine), mainly in the liver and kidneys.
The body synthesizes only about half of the daily requirement of creatine, and any deficiency must be obtained from food or supplements. Creatine is abundant in raw meat and fish, but its content is reduced by cooking.
Uses of Creatines
Creatine is used to resynthesize ATP (a substance found in cells that is necessary to store and use energy used in vital activities), which is the energy used by muscles to contract and is present in muscles as creatine phosphate.
During exercise, the energy generated when ATP is broken down is used, but because there is a limit to the amount of ATP, the resynthesis of ATP by creatine phosphate is necessary for continued exercise. Creatine has the effect of increasing endurance and muscle strength during exercise and other physical activities, so creatine’s ability to increase athletic performance is useful mainly during repetitive, short, intense exercise.
In addition to athletes, the effects of creatine on the athletic performance of the elderly are also being studied, and the use of creatine to maintain muscle strength and rehabilitation of the elderly is being investigated.
Properties of Creatines
Creatine has a melting point (decomposition temperature) of 303°C and is slightly soluble in water, but not in ether. Creatine is found in vertebrates and facilitates the recycling of adenosine triphosphate (ATP), primarily in muscle and brain tissue.
Recycling is accomplished by converting adenosine diphosphate (ADP) back to ATP through the donation of phosphate groups. Creatine also acts as a buffer.
Other Information About Creatines
1. Biosynthesis of Creatines
Creatine is an amino acid derivative that is naturally produced in the human body from the amino acids glycine and arginine. In the first step of biosynthesis, the enzyme arginine (glycine amidinotransferase, AGAT) mediates the reaction of glycine and arginine to form guanidinoacetic acid.
This product is then methylated by guanidinoacetic acid N-methyltransferase (GAMT) using S-adenosylmethionine as the methyl donor. Creatine is phosphorylated by creatine kinase to form creatine phosphate, which is used as an energy buffer for skeletal muscle and the brain. A cyclic form of creatine called creatinine exists in equilibrium with its tautomer and creatine.
2. Handling and Storage Precautions
Precautions for handling and storage are as follows
- Keep the container tightly closed and store it in a dry, cool, dark place.
- Use only outdoors or in well-ventilated areas.
- Store away from oxidizing agents and other incompatible materials.
- Be aware that decomposition produces carbon monoxide, carbon dioxide, nitrogen oxides, and other gases.
- Wear protective gloves, eye protection, protective clothing, and protective masks when using.
- Take care not to inhale dust or aerosol.
- Wash hands thoroughly after handling.
- In case of skin contact, flush immediately with water.
- In case of eye contact, rinse cautiously with water for several minutes.