| Analysis | Description | Test Method |
| Assay (dry basis) | 99.0～101.0% | HPLC |
| Loss on drying | Not More Than 1.00% | Dryer |
| Residue on ignition | Not More Than 0.20% | Ph. Eur. |
| Related substances | Not More Than 0.10% | Ph. Eur. |
| Endotoxin* | Less Than 6.0 EU/g | Ph. Eur. |
| State of solution(Transmittance) | Not Less Than 95.0% | Ph. Eur. |
| PH | 1.4~2.0 | Ph. Eur. |
| Specific rotation[α]20D | -115～-127° | Ph. Eur. |
| Ammonium (NH4) | Not More Than 0.020% | Ph. Eur. |
| Chloride (Cl) | Not More Than 0.020% | Ph. Eur. |
| Sulfate (SO4) | Not More Than 0.020% | Ph. Eur. |
| Iron (Fe) | Not More Than 10 ppm | ICP-MS/AOAC 993.14 |
| Arsenic (As) | < 1 ppm | ICP-MS/AOAC 993.14 |
| Cadmium (Cd) | < 2 ppm | ICP-MS/AOAC 993.14 |
| Heavy metals (Pb) | Not More Than 10 ppm | ICP-MS/AOAC 993.14 |
| Mercury (Hg) | < 0.5 ppm | ICP-MS/AOAC 993.14 |
N-acetyl-L-hydroxyproline (AHYP) is an acetylated form of l-hydroxyproline that has been used orally or topically for a long time as oxaceprol (CAS 33996-33-7) to treat rheumatoid arthritis and osteoarthritis.Orally administered AHYP increased the synthesis of collagen in burn-injured skin in rabbits;healing effects have been reported in skin-ulcer patients and in porphyria cutanea tarda patients. | Total Plate Count | < 3,000 cfu/g | AOAC 990.12 |
| Total Yeast & Mold | < 300 cfu/g | AOAC 997.02 |
| E. Coli | < 10 cfu/g | AOAC 991.14 |
| Coliforms | < 10 cfu/g | AOAC 991.14 |
| Salmonella | Negative | ELFA-AOAC |
| Staphylococcus | < 10 cfu/g | AOAC 2003.07 |
N-acetyl-l-hydroxyproline (AHYP) is an acetylated form of l-hydroxyproline that is used to treat skin ulcers and porphyria cutanea tarda.