Carbohydrates and Patient Case Study

Patient Case Study

• A 40-year-old male presented at the emergency department
• Complaints: increased thirst, hunger, frequent urination, weight gain (past year)
• Examination: fasting blood glucose level of 135 mg/dL

Carbohydrate Classification

• Carbohydrates are classified into four main groups:
  • Monosaccharides
  • Disaccharides
  • Oligosaccharides
  • Polysaccharides

Monosaccharides

• Simplest form of carbohydrates
• Cannot be hydrolyzed into simpler carbohydrates
• Examples: Glucose, Fructose, Ribose, Galactose

Glucose

• Also known as "blood sugar"
• Immediate energy source
• Glycogen is its storage form

Fructose

• Sweetest sugar
• Naturally found in fruits and honey
• Also known as "fruit sugar"

Galactose

• Present in milk
• Needed for various biomolecules
• Crucial for brain and nervous tissue development in infants

Monosaccharide Importance

• Fructose: abundant in seminal fluid, a crucial energy source for sperm
• Galactose: vital for synthesizing various biomolecules, important for infant brain and nervous system development

Monosaccharide Classification (Families)

• Aldoses (aldehyde group)
• Ketoses (ketone group)

Monosaccharide Classification (Number of Carbons)

• Triose (3 carbons)
• Tetrose (4 carbons)
• Pentose (5 carbons)
• Hexose (6 carbons)
• Heptose (7 carbons)

Examples of Aldoses and Ketoses

• Aldoses: Glyceraldehyde, Erythrose, Ribose, Glucose
• Ketoses: Dihydroxyacetone, Erythrulose, Ribulose, Fructose

Stereoisomerism

• Isomers: same chemical formula, different chemical structure
• Stereoisomers: same molecular formula, same functional groups, but different spatial arrangements
• Conformational isomers: different arrangements of atoms within a molecule due to rotation around single bonds

Chiral Carbon

• Carbon atom bonded to four different groups
• Important in determining isomerism
• All monosaccharides have chiral carbon atoms, except dihydroxyacetone

D & L Isomers

• Nonsuperimposable mirror images of each other
• D-sugars predominantly found in nature
  • Example: D-Ribose, D-Glucose

Enantiomer Properties

• Rotate plane-polarized light equally but in opposite directions
  • Levorotatory (-)
  • Dextrorotatory (+)
• Optically active molecules exhibit this property

How Many Chiral Carbons?

• Determine the number of chiral carbon atoms

Epimers

• Diastereomers that differ in configuration around only one chiral carbon

Cyclization of Glucose and Fructose

• Cyclization forms cyclic structures (α and β anomers)
  • Alpha (OH below the ring)
  • Beta (OH above the ring)

Reducing Sugars

• Can act as reducing agents
• Free aldehyde (C1) or ketone (C2) group

Mutarotation

• Spontaneous interconversion of cyclic α and β anomers in solution
• Equilibrium between α and β forms

Terminologies

• Enantiomers: nonsuperimposable mirror images
• Epimers: differ only in configuration around one chiral carbon
• Anomers: differ in configuration at the anomeric carbon

Diabetes

• Symptoms: Increased thirst, frequent urination, extreme hunger, etc
• Normal fasting blood sugar: <100 mg/dL
• Prediabetes: 100-125 mg/dL
• Diabetes: ≥126 mg/dL (on two separate tests)
• Type 1 DM: pancreas fails to produce enough insulin
• Type 2 DM: cells fail to respond to insulin properly

This quiz explores the classification of carbohydrates focusing on monosaccharides, while also examining a clinical case study of a patient presenting symptoms related to glucose levels. Understand the significance of carbohydrate types and their roles in human health, especially in diabetes management.