Water soluble vitamins Ascorbic acid Antioxidant cofactor for

Water soluble vitamins

Ascorbic acid • Antioxidant, cofactor for hydroxylation reactions, for example: in procollagen: Pro→hydroxy. Pro Lys→hydroxy. Lys • Deficiency: Scurvy with sore spongy gums, loose teeth and poor wound healing • Toxicity: none

B-complex • Energy releasing: – Thiamine (vit B 6) – Riboflavin (vit B 2) – Niacin (vit B 3) – Biotin – Pantothenic acid • Hematopoietic – Folic acid – Vit B 12

B-complex • Others – Pyridoxine (vit B 6) – Pyridoxal – Pyridoxamine

Folic acid • Active form: tetrahydrofolic acid • Transfer one-carbon units: synthesis of methionine, purines, and thymine • Deficiency: megaloblastic anemia and neural tube defects [birth defects] • Administration of high levels of folate can mask vit B 12 deficiency

Vitamin B 12 • Also called cobalamin • Active form: methylcobalamin, deoxyadenosyl cobalamin • It is a cofactor for reactions like: homocysteine→methionine methylmalonyl. Co. A→succinyl. Co. A • Deficiency: pernicious anemia, dementia, spinal degeneration with signs of megaloblastic anemia and neuropsychiatric symptoms • Pernicious anemia is treated with IM or high dose oral vit B 12

Vitamin B 6 • Also called pridoxine, pyridoxamine, pyridoxal • Active form: pyridoxal phosphate • It is a cofactor for enzymes, particularly in amino acid metabolism • Signs of deficiency: glossitis and neuropathy • There’s a toxicity encountered with sensory neuropathy occuring at high doses • Deficiency can be induced by isoniazid

Vitamin B 1 • Also called thiamine • Active form: thiamine pyrophosphate • It is a cofactor of enzymes catalyzing : pyruvate→acetyl. Co. A αketoglutarate→succinyl. Co. A ribose 5 -P + xylulose 5 -P →sedoheptulose 7 -P + glyceraldehyde 3 -P • Deficiency : beri with tachycardia, vomiting, convulsions, apathy, loss of memory and eye movements

Niacin Also called: nicotinic acid, nicotinamide Active form: NAD+, NADP+ Involved in electron transfer Deficiency: Pellagra with signs of dermatitis, diarrhea and dementia • High doses of niacin are used to treat hyperlipidemia • •

Vitamin B 2 • • Also called riboflavin Active forms : FMN, FAD Involved in electron transfer Signs of deficiency include dermatitis and angular stomatitis

Biotin • Enzyme bound is the active form • Involved in carboxylation reactions • Consumption of a large amounts of raw egg whites [which contains a protein avidin, that binds biotin] can induce a biotin deficiency

Pantothenic acid • Active form is coenzyme A • It is an acyl carrier