About the Cover:

Annatto Seeds in the Laboratory. The main compound of annatto seeds, bixin, has antioxidant properties and an orange-red color, which makes annatto extract useful in the cosmetic and food industries. In the article by Teixeira, Durán, and Guterres, students encapsulate bixin in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) particles by an emulsion–solvent evaporation method, which involves colloidal chemistry concepts such as surface tension, emulsion stability, and Ostwald ripening. McCullagh and Ramos discuss the separation of bixin from annatto seeds using column chromatography. In the experiment students isolate significant quantities of the carotenoid from small quantities of plant material and learn how to choose the appropriate solvent for a chromatographic separation by analyzing several potential solvents using thin-layer chromatography. Annatto seed components are also the JCE Featured Molecules for July.