Salvestrols are found in fruit and vegetables and have been found to have anti-cancer properties. They aren't actually anti-oxidants but are instead an inactive biochemical that only becomes active in contact with a particular protein that is only present in cancer cells.
Now I don't mean to alarm you but we all have cancerous cells in our bodies at any given time. When your cells become cancerous they lose their automatic sell by date, which is when a cell naturally dies off. So one of the problems in cancer is the cancer cells outliving their welcome. Instead our immune system kills them off and you only get actual Cancer, when the immune system fails to keep them in check and so the cells don't get killed off and grow out of control. Salvestrol is harmless to your healthy cells, but when it gets incontact with a particular protein only present in cancer cells, and then it kills the cell, so it's like a cancer cell assasin.
Salvestrol is found in most fruit and veg, but is particularly high in apples, berries and cruciferous vegetables (sprouts, cabbage, cauliflower). It is in the skins so firstly don't peel your fruit and veg before eating them, but in addition it is easily washed out in water so it's much better to steam or roast your veg then boil them, as this keeps the Salvestrol content high. Steamed sprouts anyone?