Peroxidase from horseradish
SIGMA/P8125 - Type I, essentially salt-free, lyophilized powder, ≥50 units/mg solid (using pyrogallol)
Synonym: Donor:hydrogen-
CAS Number: 9003-99-0
EC Number: 232-668-6
MDL Number: MFCD00071339
Product Type: Chemical
| absorbance ratio | RZ ≥1.0 |
| form | essentially salt-free, lyophilized powder |
| InChI | 1S/H2O3/c1-3-2/h1-2H |
| InChI key | JSPLKZUTYZBBKA-UHFFFAOYSA |
| mol wt | ~44 kDa |
| Quality Level | 200 ![]() |
| SMILES string | [O+H2]O[O-] |
| solubility | 0.1 M phosphate buffer: soluble (pH 6.0) |
| H2O: soluble | |
| specific activity | ≥50 units/mg solid (using pyrogallol) |
| storage temp. | 2-8°C |
| type | Type I |
| Analysis Note: | The RZ (Reinheitszahl) is the absorbance ratio A403/A275 determined at 0.5-1.0 mg/ml in deionized water. It is a measure of hemin content, not enzymatic activity. Even preparations with high RZ may have low enzymatic activity. |
| Application: | Peroxidase from horseradish has been used: • in fecal starch analysis • to measure plasma glucose levels by Trinder method • to incubate feruloylated arabinoxylan fractions and also to evaluate oxidative coupling • in the detection of glycoproteins |
| Biochem/physiol Actions: | HRP readily combines with hydrogen peroxide (H2O2) and the resultant [HRP-H2O2] complex can oxidize a wide variety of hydrogen donors. The optimal pH is 6.0-6.5 and the enzyme is most stable in the pH range of 5.0-9.0. HRP can be conjugated to antibodies by several different methods including glutaraldehyde, periodate oxidation, through disulfide bonds, and also via amino and thiol directed cross-linkers. It is smaller and more stable than the enzyme labels β-galactosidase and alkaline phosphatase.Hence, it is the most desired label. Also, its glycosylation leads to lower non-specific binding. It is also used for the determination of glucose and peroxides in solution. Sodium azide, cyanide, L-cystine, dichromate, ethylenethiourea, hydroxylamine, sulfide, vanadate, p-aminobenzoic acid, and Cd2+, Co2+, Cu2+, Fe3+, Mn2+, Ni2+, Pb2+ ions are known to inhibit the enzyme activity. |
| Biochem/physiol Actions: | When incubated with a substrate, horseradish peroxidase produces a coloured, fluorimetric, or luminescent derivative of the labeled molecule, allowing quantification. |
| General description: | Horseradish peroxidase is isolated from horseradish roots (Amoracia rusticana) and belongs to the ferroprotoporphyrin group of peroxidases. HRP is a single chain polypeptide containing four disulfide bridges. It is a glycoprotein containing 18% carbohydrate. The carbohydrate composition consists of galactose, arabinose, xylose, fucose, mannose, mannosamine, and galactosamine depending upon the specific isozyme. Its molecular weight (~44 kDa) includes the polypeptide chain (33,890 Daltons), hemin plus Ca2+ (~700 Daltons), and carbohydrate (~9,400 Daltons). At least seven isozymes of HRP exist. The isoelectric point for horseradish peroxidase isozymes ranges from 3.0 - 9.0. |
| Other Notes: | One pyrogallol unit will form 1.0 mg purpurogallin from pyrogallol in 20 sec at pH 6.0 at 20 °C. |
| Other Notes: | View more information on peroxidase at www.sigma-aldrich.com/enz . |
| Packaging: | 5000, 25000, 50000, 100000, 200000 units in glass bottle |
| Symbol | GHS08 |
| Signal word | Danger |
| Hazard statements | H317 - H334 |
| Precautionary statements | P261 - P272 - P280 - P284 - P302 + P352 - P333 + P313 |
| RIDADR | NONH for all modes of transport |
| WGK Germany | WGK 3 |
| activity | specific activity: ≥50 units/mg solid (using pyrogallol) |
| Storage Temp. | 2-8°C |
| Enzyme Commission (EC) Number | 1.11.1.7 ( BRENDA ![]() ![]() |
| UNSPSC | 12352204 |


