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Intersection 5
10/3/05
Reading: 9.6 p409 – 418;
3.12 p111-113
Material for this lecture taken from Laursen, S; Mernitz, H. Would You Like Fries
with That? The Fuss About Fats in our Diet; Wiley & Sons: New York , 2000.
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Gateway Chemistry 130/125/126
Section 600
6 – 7:30 PM Monday October 9th
Room 1230 USB
A Gateway to Information Storage and Expression
How does nature store and express information?
How does nature’s way compare to our computers and hard drives?
What is the impact of this understanding and resulting technologies?
Special Guest: Dr. David Burke
(UM Human Genetics Department)
Dinner Provided Please RSVP by email to Prof Banaszak Holl
(mbanasza@umich.edu)
Gateway evenings are optional
and will not affect your course grade
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Outline
• Bond length
• Molecular polarity
• Intermolecular Forces
–
–
–
–
The trio of forces
Olestra
Vitamins
Macronutrients and diet
• Betacarotene
• Vitamin D in OJ
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Bond Order
• Single bond - first order
• Double bond = second order
s orbitals
s + p orbitals
• Triple bond  third order
s + p + p orbitals
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Bond Length (pm):
the distance between
the nuclei of two bonded atom
H-F
H-Cl
H-Br
H-I
C-Si
C-P
C-S
C-Cl
92
127
142
161
194
187
181
176
C=C 134
C=N 127
C=O 122
C-C
C-N
C-O
C-F
154
147
143
141
C-O 143
C=O 122
C≡O 113
C-C 154
C=C 134
C≡C 121
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Polarity of Molecules: Maps of
Electron Density
+
-
BrF5
CHCl3
H
F
F
F
F
Cl
Cl
Br
F
C
Cl
A
SCN
S
-1
C
N
S
C
N
-1
A
Is it SO2 or H2O?
O
H
H
-1
O
+1
+1
S
S
O
O
-1
O
A
Molecular Polarity
• NO2• ClF3
Intermolecular Forces
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1) Why do we have to take some vitamins
everyday (B and C), while our body stores
others well?
2) Why are vitamins A, D, E, and K added to
any products containing Olestra?
Picture from: http://enquirer.com/editions/2000/06/23/oleanproducts.jpg
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H3C
CH3
CH3
CH3
HO
H3C
Vitamin A
N+
N
OH
CH3
CH3
NH2
OH
S
N
Vitamin B1
CH3
H
CH3
O
CH3
O
HO
HO
OH
Vitamin D
CH3
CH3
CH3
CH3
O
HO
H
CH3
Vitamin C
H3 C
CH3
CH2
HO
Vitamin E
O
CH3
CH3
O
Vitamin K
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Olestra
Olestra is a fat substitute developed by Proctor and Gamble and
used to make Ruffles WOW! Potato chips.
Serving Size 1 oz (28 g/ about 17 chips)
Total fat 0 g (Original Ruffles 10 g)
Total Calories 75 (Original Ruffles 160)
Ingredients: potatoes, olestra (Olean® brand), salt, alphatocopheryl acetate (vitamin E), vitamin A palmitate, tocopherols
(to protect flavor), vitamin K, and vitamin D.
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Hypothesis
1) Why do we have to take some vitamins
everyday (B and C), while our body stores
others well?
2) Why are vitamins A, D, E, and K added to
any products containing Olestra?
• What is your hypothesis?
• How would you test it?
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Testing the Hypothesis
Step 1: Separate
– Vitamins added to test tube with water and ligroin and
shaken…which layer is on top? How do you know?
Ligroin - a complex mixture which includes
H3C
H3C
H2
C
H2
C
C
H2
C
H2
H2
C
H2
C
C
H2
C
H2
H2
C
H2
C
CH3
C
H2
CH3
H2C
H2C
H2
C
C
H2
H3C
CH2
CH2
CH2
CH3
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Spectroscopy
Step 2: Test
Molecules (containing double bonds) typically absorb
light in the UV region of the spectrum. Water and
ligroin do not absorb light in the same region of the UV
spectrum.
Shine UV light through the water layer or the “oil”
layer sample to a detector
Measure the intensity of the light going into the
sample and the intensity of the light coming out.
Determine if sample absorbed light
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H3C
CH3
CH3
CH3
OH
CH3
Vitamin A
Retinol
Cartenoids such as betacarotene converted to retinol
Vision bone growth, cell division and differentiation
Eggs, milk, liver, fortified cereals
Carrots, cantaloupe, sweet potatoes, and spinach
A
V ita min A
2.5
ligroin
water
2
Absorbance
1.5
1
0.5
0
250
300
350
400
450
-0.5
Wavelength (nm)
500
550
600
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Vitamin B1
CH3
NH2
N
H3 C
N
N
Thiamine
+
S
OH
Nervous systems, muscles, heart
Vitamin B1
Kidney, liver, flour, beans, pork,
salmon, soybeans, wheat germ
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V ita min B1
1.4
ligroin
water
1.2
1
Absorbance
0.8
0.6
0.4
0.2
0
250
300
350
400
450
-0.2
Wavelength (nm)
500
550
600
A
Vitamin C
HO
H
Ascorbic acid
O
O
HO
HO
OH
Vitamin C
Anti-oxidant, free-radical scavenger
Pepper, citrus, tomatoes, melons,
broccoli, green leafy veggies
A
V ita min C
2.5
ligroin
water
2
Absorbance
1.5
1
0.5
0
250
300
350
400
450
-0.5
Wavelength (nm)
500
550
600
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Vitamin D
CH3
CH3
CH3
CH3
Vitamin D
H
CH2
HO
Group of steroids called
cholecalciferol
Regulate calcium, phosphorous,
bone mineralization
Enough sun and don’t need
supplement; found in egg yolk and
fish oil, fortified food products
Reported soluble in ligroin
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Vitamin E
CH3
CH3
CH3
CH3
CH3
Alpha-tocopherol
H3C
O
HO
CH3
CH3
Vitamin E
Antioxidant
Vegetable oils, nuts,
green leafy veggies,
fortified cereals
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V ita min E
2.5
ligroin
water
2
Absorbance
1.5
1
0.5
0
250
300
350
400
450
-0.5
Wavelength (nm)
500
550
600
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Vitamin K
O
O
Vitamin K
Synthesis of proteins that regulate coagulation and anticoagulation
Leafy greens, cauliflower, liver
Synthesized by bacteria in large intestine
A
V ita min K
2.5
ligroin
water
2
Absorbance
1.5
1
0.5
0
250
300
350
400
450
-0.5
Wavelength (nm)
500
550
600
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H3C
CH3
CH3
CH3
HO
H3C
Vitamin A
H
O
HO
OH
S
N
Vitamin B1
O
Fat soluble (hydrophobic)
CH3
CH3
CH3
Vitamin D
H
CH3
CH3
CH3
CH3
CH3
O
CH3
OH
Vitamin C
HO
N
Water soluble (hydrophilic)
HO
H3 C
+
N
OH
CH3
CH3
NH2
CH2
HO
Vitamin E
O
CH3
CH3
O
Vitamin K
A
1) Why do we have to take some vitamins
everyday (B and C), while our body stores
others well?
2) Why are vitamins A, D, E, and K added to
any products containing Olestra?
A
H OH
C CH2
H
O
C
HO
H OR
C
HO
C
H
H
C
OH
C CH2
H
HO
O
C H
C
C
H
C
C
H
RO
OH
C
OH
H
OR
O
OR
C H
Sucrose, sugar
H2
C
C
O
H2C
O
HC
O
C
H2
C
H2
H2
C
C
C
H2
H2C
O
H2
C
H2
C
C
H2
H2
C
C
H2
HC
CH
C
H2
H2
C
C
H2
HC
H2
C
H
C
H2
C
H2
H2
C
CH
C
H2
H2
C
C
H2
H2
C
C
H2
C
C
OR
H
H2
C
CH3
R=
C
H2
H2
C
C
H2
C
CH2
OR
O
H2
C
C
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
HC
C
H2
CH3
C
H2
O
H2
C
C
C
H2
H2
C
C
H2
H2
C
C
H2
HC
C
H2
Fat
H2
C
CH
C
H2
H2
C
C
H2
H2
C
C
H2
H
O
CH2
OH
O
C
H
RO
CH2
O
C
RO
O
CH2
H
CH3
C
H2
Olestra
H2
C
CH
C
H2
H2
C
C
H2
H2
C
C
H2
CH3
C
H2
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From Olean ® Website
In January 1996, the FDA approved the use of olestra in salty
snacks; Olean has been on the market since 1998 (Frito
Lay and Pringles)
First FDA approved fat replacer that doesn’t “break down” at
high temperatures
Hundreds of clinical tests have validated the safety of olestra
“One of the most studied food ingredients EVER.” “30 years
of testing and research” ”Many medical doctors and
culinary experts support the use of olestra-based products”
More than 3 billion servings (210 million lbs of chips or 70
million lbs of olestra) have been consumed by Americans.
www.olean.com (accessed October 2006)
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Theater Test
• 1,092 people, aged 13-88, watched a movie and
ate up to 13 oz of chips (Olestra or TG)
• Median consumption of Olestra (60g vs 77 g)
lower and taste lower (5.6 vs 6.4) on 9 point scale
• No difference in GI symptoms
– TG 93 of 529 (17.6%)
– Olestra 89 of 563 (15.8%)
• Funded by P&G
JAMA 1998, 279, 150-153.
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Center for Science in the Public Interest
• Procter & Gamble's own studies prove olestra causes
diarrhea, cramps, and other symptoms.
• FDA has more than 20,000 complaints about olestra in its
files--more than it has for all other food additives in history
combined.
• “Olestra may cause loose stools and abdominal cramping”
printed on package
www.cspinet.org/ (accessed October 2006)
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Vitamin Concerns
Procter & Gamble's eight-week clinical studies:
– 8 gm/day (~16 olestra-containing potato chips) blood
serem carotenoids, alpha-carotene, beta-carotene,
lutein, and lycopene levels were down by 50% to 60%
by the end of the studies
– 32 gm/day of olestra reduced total serum levels by 70%
Vitamin K is really important:
– Drug efficacy of anticoagulant Coumadin (1.5 million)
sensitive to fluctuations in vitamin K levels.
– bone formation in fetal development and childhood and
retention of bone in older women linked to vitamin K
www.cspinet.org/ (accessed October 2006)
Olestra’s Fate
• Sales of chips declined by 60%
• Approval not sought for other uses
• P&G sold the factory
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Question 3
In the body, vitamin D is concentrated in the skin,
liver, and kidneys. Vitamin A is found in the liver
and kidneys and in membranes such as the mucus
membranes and the retina of the eye. Excess
vitamin A accumulates in the liver, and excess
vitamin D in the kidneys.
What can you infer from these facts about the fat
content of these tissues?
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Question 4
Why are deficiencies of vitamin D, E, and K
rare, but deficiencies in vitamins C and B
much more common?
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How can we increase Vitamin
absorption in the body?
• "In 1958, Roels and coworkers studied a group of
Rwandan schoolboys who had low vitamin A levels in
their blood. They divided the boys into three groups. One
group ate 200g of carrots per day,[1] containing about 25
mg of beta-carotene, a compound that is equivalent to
vitamin A in the body. A second group of boys received 20
mL of olive oil along with the same amount, 200g, of
carrots. The third group of boys at no carrots but were
given 28 mg beta-carotene dissolved directly in the olive
oil."3
•[1] From Laursen, S; Mernitz, H. Would You Like Fries with That? The Fuss About Fats in our
Diet; Wiley & Sons: New York , 2000. The study is from Roels, O. A.; Trout, M.; et. al.
"Carotene Balances in Boys in Rwanda Where Vitamin A Deficincy is Prevalent," J Nutr. 1958,
65, 115-218.
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The following graph shows the blood plasma level of carotenes,
the family of compounds related to beta-carotene, in micromoles
carotene per liter of plasma vs. time.
Interaction of dietary beta-carotene and vegetable oil
Plasma Carotenes (uM)
12
10
8
6
200 gms carrots/day
carrots + 20 mL olive oil
4
28 mg beta-carotene + olive oil
2
0
0
5
12
19
26
31
Days of Dietary Supplement
Data from Roels, Trout, and Dejacquier, 1958
What can you conclude from the graph?
Figure from: http://www.hsph.harvard.edu/Academics/nutr/olestra/fig6.html
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Questions 5-6
5) Suggest some reasons why the beta-carotene dose
may have been more effective in raising blood
plasma levels of carotene than the carrots, even
when both were given with olive oil. Does that
mean that beta-carotene supplements are better
for you than carrots? Why or why not ?
6) Why do blood carotene levels seem to level out
after a few days of dosage?
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Note
Similar experiments have shown that other
carotenoids (plant-derived nutrients with
chemical structures similar to carotene) are
also absorbed better in the presence of oil.
Other experiments show, moreover that the
oil must be digestible. When indigestible
(but safe to eat) mineral oil is given with the
carotene, blood carotene levels do not rise.
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The Trio of Intermolecular
Interactions
I. London Dispersion Forces
– All molecules
– Related to the polarizability of a molecule or
how distortable the molecule’s molecular
orbital is.
– Larger = more easily distorted
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Question 7
Explain this trend:
CH4
Boiling
point (oC)
-164
CH3CH3
-89
CH3CH2CH3
-42
C5H12
36
C6H14
69
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II. Dipole-dipole
Molecules that have dipoles interact
Cl
Cl


Cl
C
Cl
H
+

 Cl
C
Cl
H
+
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Question 8
Acetone and chlorine both have the same molecular
weight. Acetone boils at about 58 °C, whereas
chlorine boils at –34 °C. Explain why there is such
a large difference in their boiling points.
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Acetone has the following structure:
H
C
H
H
C
H
C
H
H
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III. Hydrogen Bonding
• Especially strong dipoledipole
• N-H, O-H, F-H
• Intermolecular (dashed
+


lines)
H
F

+
H
-

+
F
H
H
+

-
F
-
F
Picture from:
http://www.elmhurst.edu/~chm/vchembook/i
mages/122hbondwater.JPEG
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Question 9
Hydrogen bonding can also occur between
different kinds of molecules. For example,
an ammonia (NH3) molecule and a water
(H2O) molecule. Draw ammonia and water,
and any hydrogen bonding that could occur
between them.
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Reference Sources
Primary sources are, “original, first-hand
documents” 1
Examples: journal articles; research reports
Secondary sources are, “works that interpret or
analyze the content of the primary sources.”2
Examples: Reference books, text books, scholarly
publications, encyclopedias
1
http://www.lib.umich.edu/ugl/classes/eval/
2
http://www.lib.umich.edu/ugl/guides/assist/assignments/primarysources.html
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Wikipedia
•
•
•
•
•
Dynamic
Current
Good overview or starting place
No peer review
Anyone can change anything
“As with any source, especially those of unknown
authorship, you should be wary and
independently verify the accuracy of Wikipedia
information if possible”1
1http://en.wikipedia.org/wiki/Wikipedia:Citing_Wikipedia
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The Internet
• Useful for pointing to primary sources
• Evaluate each web page for its sources
• Use the library resources. These will point
you to a variety of edited databases.
• http://searchtools.lib.umich.edu
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Exam
• 8:00 pm TONIGHT in CHEM 1400
• Ethics of exam taking
• Regrades (by Friday, October 13th)