Creatine

The mean creatine level in the urine of 50 patients with muscular dystrophy was 3.56 mmol/L which is much higher than that of the controls 0.24 mmol/L(1). The mean level of creatine in the blood of patients with uremia was 0.1 mmol/L which is over twice that of the controls blood level of 0.04 mmol/L(1).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 24(SRC), determined from a water solubility of 1.33X10+4 mg/L(2) and a regression-derived equation(3), indicates that creatine is expected to have very high mobility in soil(SRC). The pKa values for the amino and carboxylic acid moieties of creatine are estimated to be 12.7 and 3.8(4), respectively, indicating that this compound will primarily exist as a zwitter ion and zwitter ions do not volatilize from moist soil surfaces. Creatine is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 7.9X10-4 mm Hg(SRC), determined from a fragment constant method(5). Creatine has been reported to be degraded by activated sludge(6).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 24(SRC), determined from a water solubility of 1.33X10+4 mg/L(2) and a regression-derived equation(3), indicates that creatine is not expected to adsorb to suspended solids and sediment(SRC). The pKa values for the amino and carboxylic acid moieties of creatine are estimated to be 12.7 and 3.8, respectively(4), indicating that this compound will primarily exist as a zwitter ion and zwitter ions do not volatilize from water surfaces. According to a classification scheme(5), an estimated BCF of 3(SRC), determined from its water solubility(2) and a regression-derived equation(3), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Creatine has been shown to be degraded by activated sludge(7).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), creatine, which has an estimated vapor pressure of 7.9X10-4 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), will exist solely in the vapor phase in the atmosphere. Vapor-phase creatine is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 4 hours(SRC), calculated from its rate constant of 9.5x10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Creatine does not absorb light at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

In the muscles, a fraction of the total creatine binds to phosphate - forming creatine phosphate. The reaction is catalysed by creatine kinase, and the result is phosphocreatine (PCr). Phosphocreatine binds with adenosine diphosphate to convert it back to ATP (adenosine triphosphate), an important cellular energy source for short term ATP needs prior to oxidative phosphorylation.

The Koc of creatine is estimated as 24(SRC), using a water solubility of 1.33X10+4 mg/L(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that creatine is expected to have very high mobility in soil.

AEROBIC: Creatine has been reported to be aerobically degraded by activated sludge(1).

ANAEROBIC: Creatine, at a concn of 500 umol/10 ml, was fermented into methane by methanogenic enrichment cultures from Leine River mud (lake Kolksee, Germany) and black pond mud, containing Methanosarcina barkeri(1). Creatine was fermented into methane with an efficiency of 1.59 moles of methane/mole of creatine(1). Creatine did not support growth of a pure culture of M. barkeri(1).

An estimated BCF of 3 was calculated for creatine(SRC), using water solubility of 1.33X10+4 mg/L(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low.

The pKa values of the amino and carboxy moieties of creatine are 12.7 and 3.8(1), respectively, indicating that this compound will primarily exist as a zwitter ion and ions do not volatilize from water or moist soil surfaces. Creatine is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 7.9X10-4 mm Hg(SRC), determined from a fragment constant method(2).

The rate constant for the vapor-phase reaction of creatine with photochemically-produced hydroxyl radicals has been estimated as 9.5X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 4 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Creatine is not expected to undergo hydrolysis in the environment due to the lack of hydrolyzable functional groups(2). Creatine does not absorb at wavelengths >290 nm(3) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

An amino acid found mainly in skeletal and cardiac muscle; Involved in the transfer of high energy phosphate in muscle cells; [Merck Index] Used in the diagnosis of myocardial dysfunction and as a dietary supplement to enhance athletic performance; [HSDB]

Used in diagnosis of myocardial disfunction; dietary supplement for exercise performance

For nutritional supplementation, also for treating dietary shortage or imbalance

Glycine, N-(aminoiminomethyl)-N-methyl-: ACTIVE

The literature suggests that some pharmaceutically active compounds originating from human and veterinary therapy are not eliminated completely in municipal sewage treatment plants and are therefore discharged into receiving waters(1). Wastewater treatment processes often were not designed to remove them from the effluent(2). Selected organic waste compounds may be degrading to new and more persistent compounds that may be released instead of or in addition to the parent compound(2).

Commercially isolated from meat extracts