Glutathione
Reduced glutathione (GSH) is a tripeptide with a free thiol group. Glutathione disulfide (GSSG) contains two glutathione units joined by a disulfide bond. When a label or report says only “glutathione”, establish which species it describes before interpreting its mass or analytical result. [1] [2]
Reduced reference entity
In GSH, glutamate links to cysteinylglycine through its side-chain carboxyl group. ChEBI gives the neutral reference species the formula C10H17N3O6S and average mass 307.328 Da. That value applies to this reduced reference structure. [1]
| Record | What it must define |
|---|---|
| GSH | Reduced entity being discussed or measured |
| GSSG | Disulfide entity being discussed or measured |
| Total glutathione result | Which species and calculation basis are included |
| Nominal product amount | The form and mass basis represented by the label |
Glutathione-disulfide reductase links one GSSG molecule with two GSH molecules in an NADPH-dependent reduction. When a report gives “total glutathione”, check whether its result is expressed in GSH equivalents and which species were measured. A total alone does not give the individual GSH and GSSG amounts. [2]
How sample handling can change a GSH/GSSG result
Giustarini and colleagues found that oxidation during the handling of cultured cell samples could make measured GSSG appear higher. The experiment identifies a source of measurement error. It did not test storage stability in a sealed commercial vial. [3]
If a report gives an unexpectedly high GSSG result, identify when and how the sample was collected, how oxidation was controlled and which analytical method separated the two species. Those details help distinguish an issue with the material from a change introduced during analysis.
Resolve the commercial amount
The glutathione 1500 mg listing states a nominal mass. Ask whether the specification identifies GSH, GSSG or another stated form and what the 1500 mg refers to. Use the reduced reference molar mass only once the material and quantity basis match it.
The redox chemistry guide explains the GSH/GSSG relationship in more depth. Mass and molarity covers the calculation once the chemical and quantity inputs are established.
Keep storage evidence specific
For an unopened container, request the documented conditions and period for that form, closure and lot. For a prepared working sample, record its own history. The storage and stability guide and batch-document route help identify which evidence applies.
Continue the material check
| Resource | Why open it |
|---|---|
| Longevity and Mitochondrial Research Compounds | Browse the ageing, mitochondrial and redox research category. |
| Compound Index | Find another molecular profile without confusing it with a vial. |
| NAD+, MOTS-c and Glutathione Compared | Compare three chemical classes associated with metabolic research. |
| GHK-Cu | Resolve copper-complex identity and the mass basis for GHK-Cu. |
Sources and scope
- ChEBI. Glutathione, CHEBI:16856.Curated identity, structure, formula and average mass of reduced glutathione.
- IUBMB. Glutathione-disulfide reductase, EC 1.8.1.7.IUBMB enzyme nomenclature and reaction stoichiometry for glutathione-disulfide reductase.
- Giustarini et al. (2015). Thiol/disulfide analysis in cell cultures. Free Radical Biology and Medicine.Original cultured-cell method study demonstrating the effect of sample handling on glutathione disulfide measurements.