The Application of L-(+)-Ergothioneine in Cosmetics

L-(+)-Ergothioneine (EGT) is a potent, non-toxic, and highly stable antioxidant synthesized by fungi, algae, and bacteria, but not by animals or higher plants. Mushrooms are considered the richest natural source of EGT, with a content of 0.15–7.27 mg/g in dried mushrooms. Pharmacological studies have shown that it possesses benefits such as antioxidant, anti-inflammatory, nerve damage antagonism, cardiovascular protection, reproductive health promotion, prevention of eye diseases, prevention of tumors, central nervous system diseases, and diabetes, and is widely used in cosmetics, dietary supplements, and pharmaceuticals.

Structural Characteristics

L-(+)-Ergothioneine has a betaine configuration, with a sulfur atom attached to an imidazole ring, and exists in two tautomer forms: thiols and thioketones (Figure 1). Under physiological pH conditions, the thioketone form predominates, making EGT stable despite the presence of thiol groups^[1].

L-(+)-Ergothioneine as an Effective Skincare and Anti-Photoaging Ingredient

Studies have shown that L-(+)-Ergothioneine can protect skin fibroblasts from UV damage and improve skin hydration. It can increase reduced glutathione levels and effectively prevent the "common deletion" of mtDNA associated with photoaging. Its mechanism may involve protecting mitochondrial DNA from damage caused by reactive oxygen species generated during electron transport^[2].

L-(+)-Ergothioneine in Sunscreen Products

Ergothioneine can be combined with avobenzone (a highly effective chemical sunscreen), ferulic acid, etc., to form a dual supramolecular complex (AVB–FA–EGT). This dual supramolecular system exhibits enhanced broad-spectrum UV protection, photostability (up to 8 hours), and sun protection efficacy (15.93 times higher SPF). Furthermore, AVB–FA–EGT also exhibits strong antioxidant properties, biocompatibility, negligible permeability, and excellent safety^[3].

References:

[1] SHUN SATO. Biosynthesis of ergothioneine: current state, achievements, and perspectives[J]. Applied Microbiology and Biotechnology, 2025, 109 1. DOI:10.1007/s00253-025-13476-4.

[2] K. BAZELA. L-Ergothioneine Protects Skin Cells against UV-Induced Damage—A Preliminary Study[J]. Cosmetics, 2014, 1 1: 51-60. DOI:10.3390/COSMETICS1010051.

[3] LU B, RUAN B, ZHANG J, et al. Supramolecular avobenzone sunscreen: a promising method for enhancing UV protection and photostability[J]. Journal of Materials Chemistry B, 2025, 47: 15362-15371. DOI:10.1039/D5TB01899D.