Easy to use microbiological microtiter plate test for the quantification of total vitamin B2 (enriched and natural vitamin B2) in food, feed and pharmaceutical products.
Vitamin B2 is extracted from the sample and the extract is diluted. The diluted extract and the vitamin B2 assay-medium are pipetted into the wells of a microtiter plate which is coated with Lactobacillus rhamnosus. The growth of Lactobacillus rhamnosus is dependent on the supply of vitamin B2. Following the addition of vitamin B2 as a standard or as a compound of the sample, the bacteria grow until the vitamin is consumed. The incubation is done in the dark at 37 °C (98.6 °F) for 44 – 48 h. The intensity of metabolism or growth in relation to the extracted vitamin B2 is measured as turbidity and compared to a standard curve. The measurement is done using a microtiter plate spectrophotometer at 610 – 630 nm (alternatively at 540 – 550 nm).
|Test format||Microtiter plate with 96 wells (12 strips with 8 removable wells each)|
|Sample preparation||For the determination of added and total vitamin B2 the sample has to be treated with enzymes and thereafter heat extracted.|
|Incubation time||44 - 48 h in the dark at 37 °C (98.6 °F)|