I am going to talk about astaxanthin today.
This is also an essential raw material for blueberry-based health food. The available data are robust, in terms of both quality and quantity, and it is a material with proven effects. However, just like bilberry and lutein, astaxanthin will be displayed as "Haematococcus algae extract (containing 5% astaxanthin)" in ingredient labels. Because there are materials with different contents, such as 0.5% and 1%, the amount of Haematococcus algae extract alone tells nothing about how much astaxanthin the product contains.
Detailed description of astaxanthin is available here. http://www.astaxanthin.co.jp/
I can't help but write something, so I am going tell you a trivia, which cannot be found in the above-referenced site. If you are breeding goldfishes, particularly "Ranchu", I would like to call your attention. Their body color will become brighter red if you add astaxanthin to feed. Similarly, it will become yellowish red, if lutein is given. This is because the red color pigment on the goldfish body surface is astaxanthin. While carp can metabolize lutein to yield astaxanthin, goldfish cannot. I'm sorry … this was digressional.