# Valorization of Amphidinium carterae for Integrated Preparation of Peridinin and Diadinoxanthin Cycle Carotenoids

## TL;DR

This study develops a new method to efficiently extract high-purity carotenoids from the microalga Amphidinium carterae for potential biorefinery applications.

## Contribution

The first integrated method for preparing peridinin and diadinoxanthin cycle carotenoids from wet A. carterae with high purity and recovery rates.

## Key findings

- The method achieved purities over 95% for peridinin, diadinoxanthin, and diatoxanthin.
- Total recovery rates were approximately 70%, 51%, and 74% for the respective compounds.
- NMR confirmed the purified compounds as all-trans isomers.

## Abstract

An integrated microalgae biorefinery producing high-purity xanthophylls using a sustainable and efficient strategy still faces critical challenges. In this study, the microalga Amphidinium carterae can accumulate peridinin and diadinoxanthin cycle carotenoids. Notably, valorization of wet A. carterae using integrated preparation of peridinin and diadinoxanthin cycle carotenoids was developed, containing four main steps including microalgae cultivation, solvent extraction, octadecylsilyl open-column chromatography, and ethanol precipitation for the first time. Under the optimum integrated preparation conditions, the purities of obtained peridinin, diadinoxanthin, and diatoxanthin were all more than 95%, with total recovery rates of approximately 70%, 51%, and 74%, respectively. Based on nuclear magnetic resonance techniques, the purified peridinin, diadinoxanthin, and diatoxanthin were identified as all-trans-peridinin, all-trans-diadinoxanthin, and all-trans-diatoxanthin, respectively. In all, the developed method may hold significant implications for future purification of peridinin and diadinoxanthin cycle carotenoids, as well as for the integrated biorefinery of wet A. carterae.