Biological assay of Annato (Bixa Orellana) for Vitamin A activity

Biological assay of the crude petroleum ether extract of the annato showed that it contains 1300 I.U. of vitamin A activity per gram. As one gram of the oil extract is equivalent to about 50 grams of annato seeds it is obvious that annato is not a rich source of vitamin ATests for the presence of carotene in the crude oily extract by isolating this pigment by the phase separation method proved to be negativeThe water extract concentrate of the annato when assayed on rats for vitamin A activity by ther therapeutic and preventive methods of assay did not give any response, showing that coloring food preparations with this extract will not increase their vitamin A content. (Summary and Conclusions)