Optimized separation of astaxanthin stereoisomers from microbial sources using chiral HPLC

) greater than 0.999 and a relative standard deviation (RSD) of <3.8%. This is because all-trans AST stereoisomers could undergo specific rotations or spins due to π-π interactions, hydrogen bonding, and inclusion interactions. This process allowed the successful separation of the three all-trans AST optical isomers and provides a theoretical basis for large-scale preparation of all-trans AST stereoisomers from different sources.