Abstract:Astaxanthin is a natural terpene unsaturated compound, which has two β-ionone ring and eleven conjugated double bonds in the molecular structure. As the only one carotenoid that can pass through the blood-brain barrier, astaxanthin has numerous biological activities beneficial for human health. In recent years, astaxanthin has attracted much attention in the fields of food, medicine, biology and cosmetics due to its excellent antioxidant properties. As a naturally occurring carotenoid, astaxanthin can be spontaneously aggregated in the hydrated organic solvent, thus presenting different forms of existence, such as yellow H aggregates, orange M monomer, and pink-purple J aggregates, and different kinds of carotenoid aggregates could make a big difference in color, structure, optical property, biological activity, and so on. This article mainly focuses on the formation mechanism of aggregates, influence factors, detection methods (ultraviolet-visible spectroscopy, transmission electron microscope, circular dichroism, Raman spectroscopy, fluorescence spectroscopy, molecular simulation method, etc.) and the application prospect of astaxanthin aggregates in recent ten years, in order to lay a foundation for future astaxanthin aggregates physiological activity and application research.
