HSS 2342 Lecture Notes - Lecture 13: Collagen, Peroxidase, Vitamin K
28 Mar 2017
School
Department
Course
Professor
Document Summary
The antioxidant nutrients: an overview: antioxidant nutrients. Minerals: act as cofactors for enzymes that protect from oxidative damage. Oxidation (lose an electron) is a part of normal metabolism. Oxidation (lose) is paired with reduction (gain) reactions, with the unpaired electrons acting as a free radical which damages lipids, dna, rna and proteins. Antioxidants neutralize these free radicals: vitamin a and beta-carotene. Vitamin a is the rst fat-soluble vitamin to be recognized. There are three different forms of vitamin a: retinol, retinal, and retinoic acid, known as the retinoids. In the body: retinol esters (in animal foods) beta-carotene (in plant foods) retinol retinal retinoic acid (supports reproduction) (participates in vision) (regulated growth) Vitamin a, once absorbed, travels in the lymph (it is fat-soluble) and eventually arrives at the liver. To travel to other tissues, retinal-binding protein is needed. Cells take up vitamin a by receptors on its surface: vitamin a: roles in the body.
