Glutathione powder (70-18-8)

Glutathione (GSH) is a tripeptide that contains an unusual peptide linkage between the amine group of cysteine and the carboxyl group of the glutamate side-chain. It is an antioxidant, preventing damage to important cellular components caused by reactive oxygen species such as free radicals and peroxides.

Thiol groups are reducing agents, existing at a concentration of approximately 5 mM in animal cells. Glutathione reduces disulfide bond formed within cytoplasmic proteins to cysteines by serving as an electron donor. In the process, glutathione is converted to its oxidized form glutathione disulfide (GSSG). Glutathione is found almost exclusively in its reduced form, since the enzyme that reverts it from its oxidized form, glutathione reductase, is constitutively active and inducible upon oxidative stress. In fact, the ratio of reduced glutathione to oxidized glutathione within cells is often used scientifically as a measure of cellular toxicity.

Glutathione was discovered by J. de Rey-Paihade in 1888 from extracts of yeast and many animal tissues (beef skeletal muscle and liver, fish skeletal muscle, lamb small intestine, and sheep brain) and in fresh egg white. de Rey-Paihade named this substance philothion meaning love and sulfur in Greek. In 1921, Hopkins suggested that the philothion isolated from liver, skeletal muscle, and yeast is a dipeptide consisting of cysteine and glutamate but these authors overlooked the presence of glycine in philothion possibly due to misinterpretation of the Van Slyke amino N data. Honoring the history of the discovery of philothion, Hopkins named the substance “glutathione.” Based on the content of nitrogen and sulfur in Glutathione isolated from yeast, blood, and liver, Hunter and Eagles indicated in 1927 that Glutathione is not a dipeptide containing Glutamate–Cysteine but is a tripeptide consisting of Glutamate–Cysteine and an additional low-molecular-weight amino acid (possibly serine). Using an acid hydrolysate of Glutathione, Hopkins proposed in 1929 that Glutathione is a tripeptide formed from cysteine, glutamate, and glycine. This proposal was supported by the independent work of Kendall and coworkers in 1929 and 1930. Based on titration of Glutathione in water and formaldehyde as well as the observed pK values, Pirie and Pinhey reported in 1929 that the structure of Glutathione is γ-Glutamate–Cysteine–Glycine. The structure of Glutathione was confirmed by Harington and Mead in 1935 through chemical synthesis from N-carbobenzoxycystine and glycine ethyl ester.

Glutathione (GSH) participates in leukotriene synthesis and is a cofactor for the enzyme glutathione peroxidase. It also plays a role in the hepatic biotransformation and detoxification process; it acts as a hydrophilic molecule that is added to other lipophilic toxins or wastes prior to entering biliary excretion. It participates in the detoxification of methylglyoxal, a toxic by-product of metabolism, mediated by glyoxalase enzymes. Glyoxalase I catalyzes the conversion of methylglyoxal and reduced glutathione to S-D-Lactoyl-glutathione. Glyoxalase II catalyzes the conversion of S-D-Lactoyl Glutathione to Reduced Glutathione and D-lactate. Glyoxalase I catalyzes the conversion of methylglyoxal and reduced glutathione to S-D-Lactoyl-glutathione. Glyoxalase II catalyzes the conversion of S-D-Lactoyl Glutathione to Reduced Glutathione and D-lactate. GSH is a cofactor of conjugation and reduction reactions that are catalyzed by glutathione S-transferase enzymes expressed in the cytosol, microsomes, and mitochondria. However, it is capable of participating in non-enzymatic conjugation with some chemicals, as it is hypothesized to do to a significant extent with n-acetyl-p-benzoquinone imine (NAPQI), the reactive cytochrome P450 reactive metabolite formed by toxic overdose of acetaminophen. Glutathione in this capacity binds to NAPQI as a suicide substrate and in the process detoxifies it, taking the place of cellular protein sulfhydryl groups which would otherwise be toxically adducted. The preferred medical treatment to an overdose of this nature, whose efficacy has been consistently supported in literature, is the administration (usually in atomized form) of N-acetylcysteine, which is used by cells to replace spent GSSG and allow a usable GSH pool.

glutathione is a peptide composed of cysteine, glycine, and glutamate. It is believed to enhance the skin’s cellular metabolism and oxygen utilization. It has been found to protect the fibroblast against free radical-induced oxidation and act as a powerful antioxidant. Studies indicate that it can inactivate the tyrosinase enzyme and quench free radicals that contribute to tyrosinase and melanin formation, thereby serving as a skin-lightening or de- pigmenting agent. glutathione is a component of plant and animal tissue, naturally occurring in the body and essential for the proper functioning of the immune system.

Glutathione Uses for Winemaking and Cosmetics

Winemaking

The content of glutathione in must, the first raw form of wine, determines the browning, or caramelizing effect, during the production of white wine by trapping the caffeoyltartaric acid quinones generated by enzymic oxidation as grape reaction product. Its concentration in wine can be determined by UPLC-MRM mass spectrometry.

Cosmetics

Glutathione is the most common agent taken by mouth in an attempt to whiten the skin. It may also be used as a cream. Whether or not it actually works is unclear as of 2019. Due to side effects that may result with intravenous use, the government of the Philippines recommends against such use.

COA

• Struzynska L, Chalimoniuk M, Sulkowski G: The role of astroglia in Pb-exposed adult rat brain with respect to glutamate toxicity. Toxicology. 2005 Sep 1;212(2-3):185-94.
• Witschi A, Reddy S, Stofer B, Lauterburg BH: The systemic availability of oral glutathione. Eur J Clin Pharmacol. 1992;43(6):667-9.
• Yim CY, Hibbs JB Jr, McGregor JR, Galinsky RE, Samlowski WE: Use of N-acetyl cysteine to increase intracellular glutathione during the induction of antitumor responses by IL-2. J Immunol. 1994 Jun 15;152(12):5796-805.