PHB231 Lab (8) Vitamins PDF - October University

Faculty of Pharmacy Biochemistry Department Biochemistry 1 (PHB231) Vitamins Prepared by: T.A Mariam Sabry Under Supervision of Assoc. Prof. Sherine Mahmoud Dr. Amira Abdeldayem ILOs  Classify major types of nutrients.  Classify...

Faculty of Pharmacy Biochemistry Department Biochemistry 1 (PHB231) Vitamins Prepared by: T.A Mariam Sabry Under Supervision of Assoc. Prof. Sherine Mahmoud Dr. Amira Abdeldayem ILOs  Classify major types of nutrients.  Classify two types of vitamins (Fat vs Water soluble).  Understand the role, mechanism of action of fat soluble vitamins (D,E,K&A).  Understand the role, mechanism of action of water soluble vitamins (C&B).  Chemical identification of vitamins (C&B)  Macro vs Micronutrients Macronutrients are the nutrients needed in larger quantities & used as a source of energy. Micronutrients are mostly vitamins and minerals, and are equally important but consumed in very small amounts & not used as a source of energy. Classification Essential vitamins: can't be synthesized by human body & must be included in diet Non-Essential Vitamins: can be synthesized by human body I. Fat soluble Vitamins (Vitamins D,E,K&A)  Vitamin A Vitamin A is a group of unsaturated nutritional organic compounds including, Retinol, Retinal, Retinoic acid & carotenoids, among which is beta carotene.  Vitamin A Functions Deficiency Retinol: supports reproduction Xerophthalmia (dry eyes), Retinal: participates in vision keratinization Retinoic acid: supports growth Decreased mucosal immunity β-carotene serves as a vitamin A precursor. Some β-carotene may act as an antioxidant capable of protecting the body against disease  Vitamin D Vitamin D is obtained by irradiating provitamin D with ultraviolet light and are responsible for intestinal absorption of calcium, iron & magnesium. Available in 2 forms  Vitamin D Mechanism, absorption & Transport Vitamin D is carried on the bloodstream to the liver, where it is converted into the prohormone calcidiol In Kidneys, circulating calcidiol may then be converted into calcitriol (the biologically active form of vitamin D. Then calcitriol is released into circulation Calcitriol is transported to various body organs through binding with Vitamin D- binding protein.  Vitamin D Functions Deficiency A steroid hormone. Rickets: The bones fail to calcify normally, Major effect is to facilitate causing growth retardation and skeletal absorption of calcium from abnormalities. Osteoporosis The lack the intestine, and thereby of calcium results in bones assist in maintaining that are porous and brittle calcium homeostasis.  Vitamin E Vitamin E is a naturally occurring anti-oxidant also known as tocopherols. It is known for its anti-aging properties  Vitamin E Mechanism Free radicals such as superoxide, hydroxyl ions & nitric oxide contain unpaired electrons. Antioxidants, such as vitamin E prevent cell damage by binding with free radicals and neutralizing its unpaired electron. Vitamin E binds to OO- to form an intermediate structure that is converted to tocopherylquinone.  Vitamin E Functions Deficiency Antioxidant: protects cell Can lead to reproductive membrane, guards against ROS dysfunction, hemolytic anemia and and protects other poly unsaturated nerve damage fatty acids such as vitamin A  Vitamin K Vitamin K is also know as anti-hemorrhagic vitamin, naturally produced by bacteria in the intestine. Vitamin K is essential for production of a type of protein (prothrombin)  Vitamin K Functions Deficiency Necessary for formation of May be caused by antibiotics several blood-clotting factors in the Hemorrhage liver, and deficiency leads to Malabsorption bleeding disorders. II. Water soluble Vitamins (Vitamins B&C)  Vitamin B Complex Name Structure Function / Deficiency Vitamin B1 (Thiamine ) Essential for nerve & Muscle function Essential for carbohydrate and some amino acids metabolism Deficiency: Beri-Beri syndrome (swelling of legs, difficulty of walking, numbness) Vitamin B2 (Riboflavin ) Essential for metabolism of carbohydrates, proteins and fats. Deficiency: cheilosis (sores and cracks around mouth) Glossitis (inflammation of the tongue)  Vitamin B Complex Name Structure Function / Deficiency Vitamin B3 (Niacin) Coenzyme in energy Metabolism Deficiency: Pellagra syndrome (4D) [Dementia-Dermatitis- Diarrhea- Death] Vitamin B9 (Folic Acid ) Essential for synthesis of DNA & RNA Normal Maturation of RBCs& WBCs Deficiency: Anemia Folic acid supplements are essential during first trimester to prevent fetal deformities such as spina bifida Vitamin B6 Essential for protein metabolism Serves as catalyst Deficiency: Irritability, dermatitis & depression.  Vitamin C Ascorbic acid functions as a cofactor, enzyme complement and a powerful anti- oxidant in various reactions and metabolic processes. It also stabilizes vitamin E and folic acid and enhances iron absorption. L- ascorbic acid  Vitamin C Mechanism The chemopreventive action of vitamin C is attributed to its ability to scavenges free radicals and reactive oxygen molecules which are produced during metabolic pathways of detoxification. Also it prevents the formation carcinogens from precursor compounds.  Vitamin C Functions Deficiency Coenzyme (like vitamins B): Scurvy: Essential for the formation of collagen Bleeding gums and loosened teeth Hydroxylation of carnitine essential for Pinpoint hemorrhages fatty acids oxidation Bone fragility and joint pain Essential for the conversions of the amino Poor wound healing acids tryptophan and tyrosine to the neurotransmitters serotonin and Frequent infections norepinephrine Assists in the making of hormones such as thyroxin Antihistaminic and so very useful in relieving congestion References 1. Vaughan JG, Geissler C, Nicholson B, Dowle E, Rice E (2009). The new Oxford book of food plants. Oxford University Press US. pp. 212–. ISBN 978-0-19-954946-7. 2. Jéquier E, Constant F (February 2010). "Water as an essential nutrient: the physiological basis of hydration" (PDF). European Journal of Clinical Nutrition. 64 (2): 115–23. 3. Chipponi JX, Bleier JC, Santi MT, Rudman D (May 1982). "Deficiencies of essential and conditionally essential nutrients". The American Journal of Clinical Nutrition. 35 (5 Suppl): 1112–6.