Dairy Lactoperoxidase Test Kit

Order No.: EC0189

Lactoperoxidase (LPO) is a peroxidase naturally existing in milk. With the presence of hydrogen peroxide, it is capable of oxidizing thiocyanate ions to produce products with broad antimicrobial activity. Lactoperoxidase has an important role in the dairy cattle immune system. Lactoperoxidase is one of the most heat-stable enzymes found in milk. Pasteurization cannot deactivate it completely. Ultra-high-temperature processing will deactivate it completely. Hence, LPO is an internal index for monitoring and evaluating heat process intensity, testing the LPO activity level has been widely used in dairy production industry.

During the heat treatment of milk processing, the level heat intensity is related to the nutritional value of milk. By testing the LPO activity in milk, the nutritional value in the sample can be determined. High volume LPO indicates the milk kept most of its nutrients.

Lactoperoxidase Test Kit uses colrimetry, can quickly quantitate the LPO activity level efficiently.

【Principles】

LPO Stop Solution

LPO Substrate Blue Indicator Yellow Indicator

The kit is enzyme catalysis based. Add sample or standard to microwell plate, then pipette the Substrate solutions to the wells, the LPO in sample or standard will react with the LPO Substrate and turn blue color. After adding Stop Solution, the blue solution will change to yellow color. Read the absorbance of the wells with Microplate reader using 450nm filter. The LPO activity in the sample is positively correlated with the absorbance.

【Scope of Application】

Quantitative analysis of Lactoperoxidase in raw milk, pasteurized milk, UHT milk.

【Materials Required But Not Provided】

Devices:

—- Microplate Reader (450nm/630nm)

—- Vortex

—- Centrifuge (≥4000rpm)

—- Centrifuge tube: 50mL

—- Whatman 1# filter paper

—- Reagent reservoir (optional)

—- Constant Temperature Incubator

—- Timer

—- Micropipette: Single channel pipette (100-1000μL, 10mL)

Multi-channel pipette (30-300μL)

2. Reagent:

—- Deionized water

—- 18M concentrated sulfuric acid (H₂SO₄)

【Provided Materials and Reagent】

Component	96 wells
Microwell plate	12 × 8 wells
1 vial of Standard (Black cap, brown vial)	0.6mL, 12000U/L
Sample Diluting Buffer (White cap)	12mL
LPO Substrate (Ready-to-use, brown cap)	12mL
Concentrated Sample Extraction Buffer A (20×)	40mL
Concentrated Sample Extraction Buffer B (20×)	40mL
1.5mL centrifuge tubes with cap	15
Instruction	1
Plate Cover Sheet	2
Testing Report	1