L-Cysteine Base is a sulfur-containing non-essential amino acid important for protein structure, antioxidant defense, and metabolic functions. It plays a critical role in forming disulfide bonds in proteins, supporting hair, skin, and nail health. This high-purity grade amino acid is suitable for pharmaceuticals, nutraceuticals, and cosmetic applications. L-Cysteine Base is widely used in dietary supplements, clinical nutrition, and formulations requiring antioxidant and protein-supportive properties.