CHEM
30 B Dr.
R. Rinehart
Chapter 18 LIPIDS
I. CLASSES of lipids: based on chemical properties and
components
A. NONSAPONIFIABLE [not broken down by NaOH(aq) + heat]
1.
Steroids
2. Prostaglandins
3. Fat-soluble
vitamins: A, D, E, K
B. SAPONIFIABLE: contain groups [usually ester]
attacked by NaOH
1. Simple
a.
Waxes:
esters of long-chain fatty acids with long-chain fatty alcohols
b.
TRIGLYCERIDES:
triple esters of glycerol with fatty acids
2.
Complex
a.
PHOSPHOGLYCERIDES
b.
SPHINGOLIPIDS
II.
FATTY
ACIDS
Learn these!
See table of lipids
A. Saturated
B. Unsaturated
C.
Soaps and surfactant activity
III. TRIGLYCERIDES:
fats and oils
A. Structures
B. Physical Properties
1. Solubility; insoluble in H2O
2. Melting point: lowered by presence of cis
C=C
C. Chemical properties:
reactions
1. Hydrolysis
2. Saponification
3. Hydrogenation
D. Biological
functions
1. Energy production: 9 kcal/g [~4000 Cal/lb]
2. Energy storage
3. Insulation: blubber
IV. PHOSPHOGLYCERIDES
A. Components: glycerol, 2 fatty acids, phosphate, N-containing alcohol
B. Classes
1. phosphatidyl choline [lecithins]
2. Phosphatidyl serine or ethanolamine [cephalins]
1. Emulsifiers: why mayonnaise is made from oil and egg yolks
2. CELL MEMBRANE FORMATION
V.
SPHINGOLIPIDS
A. Sphingosine and dihydrosphingosine
B. Ceramide
= N-acyl sphingosine
C. Sphingomyelin = ceramidyl
phosphocholine
D. Cerebrosides = ceramidyl
galactose or glucose
E. Gangliosides = ceramidyl
group attached to more complex carbohydrates
F. Genetic disorders
of sphingolipid metabolism
VI. STEROIDS;
contain the
steroid ring system
[learn
to recognize it]
A. CHOLESTEROL
1. Structure and properties
2. Functions:
waterproofing skin
cell membrane component
[smears transition between gel and
fluid states -
see pictures at U Mass and CMU sites listed above]
precursor of other steroids
B. BILE SALTS; required for
fat digestion and absorption
C. STEROID hormones
1. ADRENAL
a.
GLUCOCORTICOIDS:
cortisol: raises blood sugar, increases amino acid breakdown
b.
MINERALOCORTICOIDS:
aldosterone: increases sodium recovery and potassium excretion by kidneys
a.
ANDROGENS: testosterone,
androstenedione: increases muscle mass,
body
and facial hair, other 2o sexual characteristics,
aggressiveness
VII. EICOSANOIDS:
20-carbon compounds derived from arachidonic acid or EPA
A. PROSTAGLANDINS:
produced from arachidonic acid and
“EPA”
do all sorts of things in all sorts of places; aspirin blocks synthesis
B. PROSTACYCLINS and THROMBOXANES: involved in control of
platelet aggregation
C. LEUKOTRIENES: involved in inflammatory response
| Additional resources: |
| "Meet the Fats" by Paul Reisberg at Wellesley has Chime structures of common
lipids and Olestra and other stuff. [assuming you have Chime installed -- only the Netscape version seems to work at all here] http://www.wellesley.edu/Chemistry/chem227/lipids/lipids.htm |
| Olestra pages by Dan Berger at Bluffton College;
requires Chime http://www.bluffton.edu/~bergerd/chem/olestra.html |
| a brief
PowerPoint intro to lipids by James Hardy at U Akron http://ull.chemistry.uakron.edu/genobc/Chapter_18/ |
| a topic outline from a similar course by Clarke Earley at Kent State University,
Starke Campus http://www.personal.kent.edu/~cearley/PChem/lipid/lipid.htm |
| an
illustrated outline pretty similar to mine, but prettier to look at --
doesn't have my fabulous table of lipids, though!!! http://opbs.okstate.edu/~Blair/Bioch2344/Chapter12/Chapter12.htm http://web.archive.org/web/20021219174341/http://opbs.okstate.edu/~Blair/Bioch2344/Chapter12/Chapter12.htm |
| definitions of different classes of lipids http://www.chem.qmw.ac.uk/iupac/class/lipid.html |
| How and why soap was invented by
Kevin Dunn at Hampden-Sydney College http://cavemanchemistry.com/cavebook/chsoap.html |
| check out the A to Z encyclopedia...
when you have a lot of time on your hands http://www.americanheart.org/ |
| "Long-Suffering Lipids Gain Respect"
by Jennifer Fisher Wilson, in the March 10, 2003 issue of The Scientist [free registration required, provide your email address] http://www.the-scientist.com/yr2003/mar/lcprofile_030310.html http://web.archive.org/web/20030320021337/http://www.the-scientist.com/yr2003/mar/lcprofile_030310.html takes %^&*#$@ forever to display.... |
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© Ronald W. Rinehart,
2003-7
