L-lysine

L-Lysine (CAS 56-87-1), commonly abbreviated as Lys, is an essential amino acid supplied commercially for food, feed, pharmaceutical, and personal care manufacturing.

Where is L-lysine used?

• Animal nutrition: added to swine and poultry feed to correct amino acid deficiencies in grain-based diets
• Feed for poultry and swine to correct lysine deficiency, enabling efficient rations with lower crude protein content.
• In swine feed, considered the first limiting amino acid.
• Infant nutrition uses L-lysine hydrate.
• Food: protein-fortified products, meal replacements, and functional beverages
• Sports nutrition: protein powder blends and functional drinks to support protein synthesis.
• Pharmaceutical: active ingredient or excipient in tablet formulations
• Personal care: conditioning agent and humectant in hair and skin formulations
• It cannot be synthesized by humans or most animals.

Good to know: FEMA 3847 designates its recognized status as a flavoring substance in applicable markets. Lysine-based salt forms improve the solubility of co-formulated compounds.

Formulation notes

• Excess dietary lysine at 120%, 150%, or 200% of NRC (2012) recommendations reduces feed intake and growth in weaned pigs.
• Standardized ileal digestible lysine requirements for gestating sows are 11.1 g/d (0.44% of diet) in mid-gestation and 16.1 g/d (0.58% of diet) in late gestation.
• No major differences in bioavailability have been observed between commercial lysine forms as hydrochloride, sulfate, or liquid.

Typical specification

• Heavy metals (as Pb) are at most 10 ppm.
• Arsenic content is ≤1 ppm.
• L-Lysine HCl powder contains L-Lysine ≥ 79.0% and L-Lysine HCl ≥ 99.0%.
• Liquid Lysine contains L-Lysine ≥ 50.0%.
• L-Lysine hydrate has a solubility of more than 150 g per 100 g water at 20°C.

Regulatory status

• Food supplements containing L-lysine may be brought into Germany and placed on the market if the daily dose does not exceed 800 mg L-lysine, based on a recommended intake of two capsules per day.
• L-Lysine hydrate is in accordance with the DAB monograph (German Pharmacopoeia).

Storage, packaging and handling

• Highly hygroscopic; handling is difficult during feed manufacturing if sold in pure form.

Frequently asked questions about L-lysine

What is the difference between L-lysine free base and L-lysine hydrochloride?

L-lysine is commercially supplied as free base powder as standard; L-lysine hydrochloride (L-Lys·HCl) is more widely used in feed and pharmaceutical applications.

What is the purity and composition of L-lysine hydrochloride?

L-lysine monohydrochloride (lysine-HCl) is produced by oxidative fermentation and has a minimum purity of 98%, with 78% lysine and 19-20% chlorine.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.