Volume 6, Spring 2008 - Saddleback College

Fall 2007 Biology 3A Abstracts
13. COMPARISON OF LACTATE DEHYDROGENASE ACTIVITY BETWEEN THE THRESHER SHARK
(Alopias vulpinus) AND THE PIKE MACKEREL (Cololabis saira). Robert Powers. Department of
Biological Sciences, Saddleback College, Mission Viejo, California 92692
During lactic acid fermentation that occurs in all animals and some plants, the enzyme Lactate
dehydrogenase (LDH) catalyzes the reduction of pyruvate to lactate as NADH is oxidized to NAD + .
Muscle samples were taken from A. vulpinus and C. saira to compare LDH activity between the two
epipelagic fish. Both species are quite fast and powerful swimmers, however this species of shark is
considerably larger than the pike mackerel, and because LDH activity has been found to increase as the
mass of an organism increases, it was expected that the LDH activity would be considerably higher in A.
vulpinus muscle than in C. saira muscle. A UV light spectrophotometric assay was applied to measure
∆Absorbance/minute as the substrate NADH was oxidized, and from this data LDH activity could be
calculated as mol of substrate converted per minute per gram of muscle extract. A. vulpinus had a
mean LDH activity of 635.1 mol/min/g ±66.4 mol/min/g (±SE), N=5. C. saira had a mean LDH activity
of 770.1 mol/min/g ±37.0 mol/min/g (±SE), N=5. The data actually shows that C. saira has a higher
LDH activity than A. vulpinus. Although a one tailed t-test reveals that these results are not scientifically
significant (p=0.063), it certainly seems that the original hypothesis has been invalidated. It appears that
size is not the only factor that needs to be taken into account for varying LDH activity among different
species, but furthermore a species’ unique habits and skills that nature has selected for as well.
14. THE EFFECT OF A HAIR GEL ON THE GROWTH OF MALASSEZIA FURFUR. Hanwool Park.
Department of Biological Sciences, Saddleback College, Mission Viejo, CA, 92677.
Malassezia Furfur (syn. Pityrosporum ovale), a yeast-like fungus, occurring in human skin can cause
diseases such as dandruff, pityriasis versicolar, seborrheic dermatitis, etc. Use of hair styling products
may promote the growth of the fungus and cause the diseases. However, some manufacturers claim the
preservative system, used to prevent the products from contamination by microorganisms, inhibits the
growth of the microorganisms in the scalp. A hair gel product was predicted to inhibit the growth of M.
furfur as producers claimed. Microorganisms were collected from a man’s scalp, and M. furfur was
selectively cultivated on Sabouraud’s dextrose agar medium. By using disc diffusion method, a hair gel
product was screened against the growth of the fungus. The fungi grew well, but unlike the prediction, no
inhibition zones appeared around the discs. It was suggested that a hair gel did not inhibit the growth of
M. furfur.
14. THERE IS NO SIGNIFICANT OXYGEN PRODUCTION OF SPINACIA OLERACEA PLACED INTO
CALCIUM CARBONATE SOLUTION. David Guzman. Department of Biological Sciences, Saddleback
College, Mission Viejo, California 92692
Calcium and Carbonate ions are important for plants. Plants can use Carbonate for CO 2 , and
Calcium is an important nutrient of plants. If the Calcium and Carbonate combines it becomes insoluble
in water, and this would not be beneficial for plants, so it might be logical if plants have mechanisms to
dissolve the CaCO 3 if their ions ever combined in nature. Plants need CO 2 to photosynthesize and
produce oxygen and sugars. The experiment tests whether CaC0 3 can be dissolved into ions and
produce CO 2 by an unknown mechanism in spinach. If this happens, I predict that oxygen will be
produced, and the experiment will test this idea that spinach can dissociate Calcium Carbonate. In the
experiment, Spinach disks that were cut out by cork borers and then put Petri dishes. Then 0.05 M
Calcium Carbonate was placed onto the Spinach to see if there was significant amount of oxygen
produced during a twenty minute period while expose to artificial light. There was no significant
difference between the control, de-ionized water, and the 0.05 M Calcium Carbonate solution in O 2
produced (paired t-test, p=1.00.)
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Saddleback Journal of Biology
Spring 2008