Fucoxanthin for Fat Loss

I am thinking about taking fucoxanthin prior to cardio (with some MCT’s) for fat burning. I was studying them a little bit and was wondering if my train of thought seemed accurate.

I read that they activate thermigin (UCP1) in White adipose tissue, which then increases heat production; I also read that they increase the amount of Brown Adipose Tissue in the body.

Firstly, Since they are the brown pigment from seaweed, could it be that they are merely colouring the adipose tissue brown (as I cannot see them altering the structure) since they are also fat-soluble.

Second, if they are being stored in the fat that they are destroying, could toxicity occur earlier if you lose a fair amount of body fat?