Biochem (lec)
Carbohydrates Structure and Nomenclature
• Most abundant organic compounds in the plant world • The suffix “-ose” indicates that a molecule is a
• Provide chemical energy carbohydrate
• Components of supportive structures in plants • Monosaccharides that contains aldehyde group are
• Essential components of nucleic acids called aldoses
• Ketoses – contain ketone group
Hydrate of carbon
Naming Sugars
1. Check if the oxidized carbon is aldehyde or a ketone
2. Number of carbon
Fischer Projection Formulas
• Two dimensional representation showing the
configuration configuration of a stereocenter
• Horizontal lines represent the bonds projecting forward
from the stereocenter
• Vertical line represents bonds projecting toward the rea
D- and L- Monosaccharides
• Configuration of carbohydrates commonly designated
At molecular level using the D,L system proposed by Emil Fischer in 1891
- Polyhydroxyaldehydes
- Polyhydroxyketones
Monosaccharides
the simple sugars
• Have 3-7 carbon atoms
• contain a single polyhydroxy aldehyde or
polyhydroxyketone unit
• cannot be degraded into simpler products by hydrolysis
reactions
• pure monosaccharides are water-soluble, white,
crystalline solids
, Sucrose
Importance Monosaccharides
• Most abundant disaccharide
Lactose
• Principal sugar present in milk
Galactosemia
Maltose
• From sprouted barley and other cereal grains
Disaccharides
• contains 2 monosaccharide units covalently bonded to
each other
• crystalline and water soluble substances
• upon hydrolysis they produce monosaccharides
Carbohydrates Structure and Nomenclature
• Most abundant organic compounds in the plant world • The suffix “-ose” indicates that a molecule is a
• Provide chemical energy carbohydrate
• Components of supportive structures in plants • Monosaccharides that contains aldehyde group are
• Essential components of nucleic acids called aldoses
• Ketoses – contain ketone group
Hydrate of carbon
Naming Sugars
1. Check if the oxidized carbon is aldehyde or a ketone
2. Number of carbon
Fischer Projection Formulas
• Two dimensional representation showing the
configuration configuration of a stereocenter
• Horizontal lines represent the bonds projecting forward
from the stereocenter
• Vertical line represents bonds projecting toward the rea
D- and L- Monosaccharides
• Configuration of carbohydrates commonly designated
At molecular level using the D,L system proposed by Emil Fischer in 1891
- Polyhydroxyaldehydes
- Polyhydroxyketones
Monosaccharides
the simple sugars
• Have 3-7 carbon atoms
• contain a single polyhydroxy aldehyde or
polyhydroxyketone unit
• cannot be degraded into simpler products by hydrolysis
reactions
• pure monosaccharides are water-soluble, white,
crystalline solids
, Sucrose
Importance Monosaccharides
• Most abundant disaccharide
Lactose
• Principal sugar present in milk
Galactosemia
Maltose
• From sprouted barley and other cereal grains
Disaccharides
• contains 2 monosaccharide units covalently bonded to
each other
• crystalline and water soluble substances
• upon hydrolysis they produce monosaccharides
