A Simple Colorimetric Method for Carotenoid Pigments

A Simple Test for Carotenoid Pigments in Yeasts.

The imperfect yeasts are divided by Lodder (1934) into two families, Rhodotorulaceae and Torulopsidaceae, distinguished by the occurrence of carotenoid pigments in the former. Lodder employed a form of the Molisch test to demonstrate the carotenoid nature of the pigments in Rhodotaceae. This involved covering a large mass of cells with an alcoholic potassium hydroxide solution and storing in th...

The Carotenoid Pigments

Carotenoid Pigments: Supercritical Fluid Chromatography

Carotenoids are one of the main classes of natural pigments and are found in a large number of fruits and vegetables (oranges, tomatoes, carrots) and in leaves where their presence is masked by chlorophylls until autumn. They are also found in some animal products (eggs, milk) and seafoods. Typically, carotenoids contain eight isoprenoid units bonded such that the units are reversed at the cent...

A new simple semimicro method for colorimetric determination of urea.

A Simple Colorimetric Method for the Evaluation of Chitosan

A simple sensitive and rapid colorimetric method has been developed, and herein described, for the qualitative and quantitative chemical assessment of the commercially available chitosan products. The described method relies on the reactivity of the basic amino function of chitosan with the acid dye bromocresol purple. The applied technique allows assessment of variability and selectivity chang...