| Autor: |
H.D. Eaton, J.E. Avampato |
| Rok vydání: |
1953 |
| Předmět: |
|
| Zdroj: |
Journal of Dairy Science. 36:783-793 |
| ISSN: |
0022-0302 |
| DOI: |
10.3168/jds.s0022-0302(53)91563-x |
| Popis: |
Summary Calf plasma containing “low” and “higher” amounts of carotenoids was subjected to the following treatments: saponification without separation of carotene and vitamin A; saponification followed by separation of carotene by precipitation and by chromatography on alumina; and the above treatments without saponification. After treatment, the blood samples were analyzed for vitamin A by the Kimble method on the Evelyn photoelectric colorimeter, by the Sobel method on the Coleman Model 14 spectrophotometer, and by ultraviolet absorption at 325 mμ on the Beckman Model DU spectrophotometer. Carotenoids were determined at 440 mμ on each of the above instruments. Samples read on the Evelyn were significantly lower in carotenoids than those determined on the Coleman or Beckman. Saponification and both methods of separation resulted in lower total carotenoids. Lower total vitamin A was obtained after saponification. Both colorimetric methods gave lower total vitamin A than ultraviolet absorption for both types of blood. The Kimble method gave significantly higher total vitamin A values than the Sobel method for high carotenoid blood only. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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