Diseases due to free radical are the subject of intensive study. The search aims to find substances preventing the origin of free radicals, substances capable of rendering the developed free radicals harmless, or substances capable of removing the damage of molecules which has already taken place. The present paper briefly surveys the metabolites of biogenic origin, mainly from higher plants, which show in vitro antioxidant activity and are potentially usable in a number of diseases.

        Key words: reactive forms of oxygen – biogenic antioxidants