Broccoli-sprouts extract: A broccoli sprout contains the highest nutrients, "sulphoraphane",  (which contains isothiocyanate) which is the beneficial aspect of broccoli, (at least 50 times the amount of the mature vegetable). Isothiocyanate that is in the Sulphoraphane, is responsible for stimulating enzymes in the body.

Broccoli Sprout-and Ultra-Violet radiation:
Scientists have revealed that a topical application of Broccoli extract has the ability of protecting your skin's exposure to Ultra-Violet rays (UV), which is the culprit for skin cancers, not to mention premature aging of the skin.

This activates enzymes inside the skin cells, that protects many of the damaging aspects of the Ultra-violet rays. 

The well know sun screens absorb the UV rays and has a shorter lived action of protection.  After the Broccoli extract is gone or washed away, the action stays in effect in the cells for days.