Proteins: An Overview explaining its classification, metabolism and deficiency

An Overview about Proteins. Explains about its composition, classification, sources, digestion & absorption, function, protein deficiency, PEM [Causes, Types, Prevention, Treatment] in slides extensively with pictures, diagrams, equations and flowcharts.

1. BY ASMITA CHATTERJEE GOKHALE MEMORIAL GIRLS’ COLLEGE SEM 3

2. WHAT IS PROTEINS? It is essential for nutrition, growth repair and maintenance. About 50% of protein is present in the muscles , 20% in bones , 10% in the skin and the rest in other parts of the body . The term protein, meaning ‘ to first take place ’ was introduced by the Dutch chemist Mulder in 1838 for nitrogen-containing constituent of food. Molecules which yeilds amino acids upon hydrolysis is known as Proteins.

3. Proteins contain about C=50-55% H=6-7.3% O=19-24% N=15-19% S=0-4% CHEMICAL COMPOSITION

4. 1. Based on R-group/Reaction in solution 2. Based on synthesis 3. Based on chemical composition 4. Based on structure and function 5. Based of nutritional composition CLASSIFICATIONS OF PROTEINS

5. 1. BASED ON R-GROUP/REACTION IN SOLUTION Aliphatic Aromatic Heterocyclic Sulphur containing Acidic Amino Acid Basic Amino Acid 2. BASED ON SYNTHESIS The body can manufacture many amino acids if it has an adequate nitrogen source, but it cannot produce certain others in adequate amounts to meet body needs. Those amino acids which cannot be synthesized in sufficient amounts by the body & which must be provided in the diet are essential . The human adult requires eight essential amino acids & growing children require ten amino acids. Those can be synthesized in our body are called non essential amino acids.

6. 3. BASED ON CHEMICAL COMPOSITION 4. BASED ON STRUCTURE & FUNCTION 5. BASED ON NUTRITIONAL COMPOSITION Simple Protein Conjugated Protein Derived Protein Fibrous Protein Globular Protein Complete protein Incomplete proteins

7. SOURCES OF PROTEINS Proteins can be obtained from both plant and animal sources. Proteins are present in many foods in varying amounts most proteins have been processed or modified prior to the use of human beings. Soya bean is the richest source containing 35% protein.

8. The digestion of proteins takes place in the stomach with the help of protease and pepsin enzymes, which breaks down the proteins into amino acids . The process is facilitated by the HCl acid present in the stomach. Amino acids are tiny elements which get absorbed into the blood system through the wall of the small intestine. DIGESTION & ABSORPTION OF PROTEINS Transamination

9. The amount of intake of nitrogen in food will be balanced by excretion of an equal amount of nitrogen in urine (in the form of urea mainly uric acid, creatinine and amino acids contribute to a minor extent) and faeces . NITROGEN BALANCE The body derives amino acid especially the essential amino acids from dietary protein. The best quality protein is that one that provides essential amino acids pattern very close to the pattern of the tissue proteins. PROTEIN QUALITY NI=NO In any protein the amino acid which is furthest below the standard is known as the limiting amino acid . It refers to essential amino acid that does not meet the minimal nutritional requirement available for incomplete proteins.

10. FUNCTION OF PROTEINS

11. ‘A state of relative or absolute deficiency of body proteins or one or more of the essential amino acids.’ PROTEIN DEFICIENCY ‘Protein turnover’ reflects the balance of protein degradation and resynthesis . More synthesis than breakdown indicates an anabolic state that builds lean tissues, more breakdown than synthesis indicates a catabolic state that burns lean tissues.

12. ‘A range of pathological condition arising from coincident lack of varying proportion of protein and calorie occurring most frequently in infants and young children and often associated with infection.’ Poverty and Ignorance Inadequate intra-family food distribution Presence of starchy gruels in local staple food Social mores of feeding and cultural practices Early/Abrupt/Late weaning Maternal Malnutrition Occult infectious disease Poor hygiene and water supply Poor IYCF practices Absence of caregiver CAUSES → PROTEIN ENERGY MALNUTRITION

13. KWASHIORKOR The term ‘Kwashiorkor’ means ‘sickness of weaning’. It is also known as wet protein-energy malnutrition It refers to an inadequate protein intake with reasonable calorie intake Usually appears at the age of about 2-4 years. Victims usually fail to produce antibodies following vaccination against diseases

14. CAUSES:- EFFECTS:-

15. MARASMUS The term ‘Marasmus’ means ‘ withering or wasting’. Severe protein-energy malnutrition characterized by energy deficiency and emaciation It is also characterized by stunted growth and wasting of muscles and tissue. Usually develop between 6 months to 2 years. Ofter for children who have been weaned from breast milk or suffer from chronic diarrhoea.

16. CAUSES:- EFFECTS:-

17. PREVENTION OF PEM

18. Treatment strategy can be divided as :- Resolving life threatening conditions Restoring nutritional status without disrupting homeostatis Ensuring nutritional rehabilitataion TREATMENT :- There are three stages of treatment. 1. Hospital Treatment The following conditions should be corrected: Hypothermia, hypoglycemia, infection, dehydration, electrolyte imbalance, anaemia and other vitamin and mineral deficiencies. 2. Dietary Management The diet should be from locally available staple foods - inexpensive, easily digestible, evenly distributed throughout the day and increased number of feedings to increase the quantity of food. 3. Rehabilitation The concept of nutritional rehabilitation is based on practical nutritional training for mothers in which they learn by feeding their children back to health under supervision and using local foods a) Residential units b) Day care Centres c) Domiciliary Rehabilitation

19. TREATMENT :-

20. YOU THANK BY ASMITA CHATTERJEE