By Tina Barile, Nicole Corriveau, Lauren
Gamble, and Parita Shah
LBS 145L:Ê Cell and
Molecular Biology
Section 003 Lab:Ê
Wednesday 7:00-10:00 PM
Trasi and Devin
October 18, 2006
Abstract
Native Americans made paint from organic materials for
their daily uses. They used many resources to make paints so they could express
their spirituality through vibrant colors (Galager, et al., 2006). In this
experiment, we replicated the idea of natural (made from nature) paint and
compared it to todayâs art sources in order to find similarities within past
and present paint. It would be interesting to see how paint that was used
hundreds of years ago compares to the paint used today.Ê To make natural paint, red rose petals, dirt,
and grass were liquefied and amounts of water were added to represent natural
red, brown and green colors. The basic units of the natural paint were compared
to those of the water-based Crayola¨ paint. The iodine, Barfoedâs, Benedictâs,
Bialâs and Selivanoffâs tests were all used to determine if the two types of
paints contain starch, mono- or di- and polysaccharides, and aldoses or ketoses,
respectively.Ê None of the paints,
natural or artificial, tested positive for these macromolecules.ÊÊ A chromatography test was used to compare
which substance contained more pigments.Ê
After two trials, there were no positive results for any of the paint
types.Ê A Sudan III Assay was used to
determine if there was a presence of lipids.Ê
The natural paint made from grass was the only positive result besides
the positive control.Ê
ÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊ ÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊ ÊÊÊ ÊTable 1.Ê Results of the
|
Sample |
Observations |
|
|
Positive Control (Olive Oil) |
Trial 1 |
|
|
Trial 2 |
|
|
|
Negative Control (Glucose) |
Trial 1 |
Pink |
|
Trial 2 |
Pink |
|
|
Brown Crayola¨ Water Based Paint |
Trial 1 |
Pink |
|
Trial 2 |
Pink |
|
|
Green Crayola¨ Water Based Paint |
Trial 1 |
Pink |
|
Trial 2 |
Pink |
|
|
Red Crayola¨ Water Based Paint |
Trial 1 |
Pink |
|
Trial 2 |
Pink |
|
|
Dirt |
Trial 1 |
Pink |
|
Trial 2 |
Pink |
|
|
Grass |
Trial 1 |
|
|
Trial 2 |
|
|
|
Flower Petals |
Trial 1 |
Pink |
|
Trial 2 |
Pink |
|
The Sudan III Lipids Test
determines if there is a presence of lipid molecules.Ê If the sample turned orange after applying
the Sudan III reagent, that indicates a presence of lipids.
ÊIf the sample remained turned pink after
applying the reagent, that indicates an absence of lipids.Ê The pure substances were liquefied by
measuring 5 grams of the sample and mixing it with 35.0 mL of water, giving a
concentration of 0.0142 g/mL.Ê All of the
unknown samples tested were 25% of the original concentrations.
Discussion
The purpose of our study was to determine if the paints
used by the Plains Indians is similar to the paint that we buy in the store
today.Ê To do this we used Crayola water
based paint and tested it against paint we made using dirt, grass and rose
petals.Ê We performed several different
types of tests, including Benedictâs, Barfoedâs, and Selivanoffâs, Bailâs,
Iodine,
In Benedictâs test, we examined whether or not the two
different types of paint had a free or potentially free aldehyde or
ketone.Ê A free aldehyde is a carbon ring
and is a sugar produced from the Calvin Cycle (Cooper, et al., 2006).Ê After researching the components of Crayola¨
water based paint, we found that it is made of paraffin and pigments (Binney
& Smith, 2006).Ê Paraffin is an
alkane, meaning that it consists of a carbon chain, which is not a sugar ring,
and there are no oxygenâs present which eliminates the possibility of ketoneâs
and aldehydes being present (anonymous 2, 2006).Ê The artificial paint gave a negative test
result and showed no color change like our negative control, proving a free
aldehyde or ketone group was not present.ÊÊÊ
The grass and the flower petals along with the positive control,
galactose, showed a red precipitate for both trials after heating (Figure 1).
Using Barfoedâs test, we determined that monosaccharides or
disaccharides were not present in any of the paint samples.Ê A positive test would result in a purple or
red precipitate formation after adding the Barfoedâs solution and heating the
samples.Ê The positive control,
galactose, reacted to form a purple precipitate while all of the samples
remained blue in solution with no precipitatesÊ
(Table 2 and Figure 5, 6 and 7).
Selivanoffâs test, a test based on dehydration of carbohydrates, shows
whether a ketose or aldose group is present. After being heated, an immediate
red solution indicates the presence of a ketose while heating longer would
indicate the presence of an aldose.Ê The
positive control galactose, turned red after several minutes of heating.Ê There was no color change for the Crayola¨
water-based samples.Ê However, the dirt
sample turned dark brown, the grass sample remained green with a slightly red
tint, and the flower petals turned dark pinkÊ
(Table 3 and Figure 8, 9 and 10).Ê
Another test based on dehydration of carbohydrates, Bialâs
test, which tested for the presence of furanoses, (five-member rings), was used
to further our study.Ê This result was
also negative for the artificial paint. The results for this test were all
negative (Table 4 and Figure 11, 12 and 13).
Based on the dehydration of carbohydrates, the Iodine test
for coiled polysaccharides was used to test for the presence of starch.Ê .Ê The
iodine reagent interacts with the coiled polymers in starch resulting in a
bluish black solution, which was shown with the positive control (Figure
14).Ê All of the artificial paints tested
negative for starch.Ê Anything other than
coiled polysaccharides, monosaccharides, disaccharides, non-coiled
polysaccharides and water, will not react with iodine and will remain
yellowish-brown in solution.Ê Therefore,
none of the monomers being tested for were present in the paint solutions
(Table 5 and Figure 14, 15, 16, 17 and 18).
The Bradford Protein Assay was also conducted to determine
the total protein concentration.Ê Our
results were compared against a standard curve for the quantity of proteins in
the BSA.Ê All of the Crayola¨ water-based
paint along with the dirt and petal samples tested to negative for protein
while the grass tested positive.Ê The
absorbance level for grass was 0.240 (Figure 1, 19 and 20).Ê The absorbance of grass was compared to the
determined standard curve and the grass was found to have 9.21 µg present for
every 50 µL of solution thus yielding a 0.184 µg/µL concentration.
When testing for chlorophyll, we used thin layer
chromatography (TLC) and the absorption spectrum.Ê Neither of the artificial or natural paints
separated after being painted on the TLC strip (Table 6 and Figure 21 and
22).Ê Therefore, the pigments could not
be run through the spectrophotometer.
Our last test, the Sudan III Test, was used to determine
whether or not the natural substances in the water based paint contained
lipids. After applying the Sudan III reagent to each of the samples only the
paint made from grass turned orange, indicating a positive result for that
sample (Table 7 and Figure 23).
In regards to what we know about biology and what was
involved in our experiment, we knew that paints were no longer made in the same
ãnaturalä way as before, but should show some similarities after being
tested.Ê Our results show similarities in
the sense that almost every test had a negative result for each of the
monomers.ÊÊ The results to the tests do
not show enough positive data that would support that there are significant
similarities between the natural and artificial paints.Ê In order to repeat this experiment you would
need to find a different way to test your samples.Ê A different type of paint may also help as
well as a different way of imitating the ãnaturalä paint.Ê
ÊÊÊÊÊÊÊÊÊÊÊ One problem that occurred during the
study was getting accurate samples of the natural substance that was being
liquefied.Ê The dirt, grass and rose
petals did not completely liquefy and what we did use was over-diluted.Ê In order to liquefy the ingredients more
thoroughly, we could have ground the grass and petals in the mortar and pestle
for a longer amount of time.Ê We believe
that we would have gotten more clear results if the samples would have been
prepared well.Ê By using more acetone or
another solvent, this could have helped to break up the solute in order to have
better chlorophyll readings.Ê However, we
were not aware that our samples were poorly prepared until most of the tests
had been conducted and we started to recognize a trend of negative
results.Ê Also, it is very likely that
unnatural substances could have been added to the test subjects.Ê For example, the soil or grass at one point
could have been contaminated with chemicals such as fertilizer which may have
skewed the results.Ê To avoid this next
time we would have to grow the grass and flowers ourselves in filtered
dirt.Ê