What exactly are the many benefits of Astaxanthin located in Krill Oil? Astaxanthin is an excellent-antioxidant present in Krill Oil. Microalgae while in the ocean develop higher levels of astaxanthin which are then ingested through the krill, providing them the pinkish coloring. Astaxanthin can be a keto-carotenoid, like beta-carotene and lycopene