1. CHAPTER III
RESULTS AND DISCUSSION
3.1 Experiment Results
After doing lab experiment about DNA isolation in accordance with the
procedures, we found the data that; on the use of tomatoes as the source of
DNA, DNA that can be isolated were most commonly founded in the filtrate
containing solution of Bu krim detergent. While the filtrate containing Surf
detergent solution, DNA obtained were quite a lot but still less when compared
with previous treatments. In the filtrate containing Rinso detergent powder,
DNA obtained was quite a bit. While the time required for the formation of
DNA at each treatment was varied. For tomatoes as DNA source, the fastest
time where DNA formed was in Bu krim detergent solution. Longest time
required to isolate DNA of tomatoes was in Surf detergent solution.
On the use of pear fruit as DNA sources, most of the DNA obtained from
the filtrate containing solution of Bu krim, whereas little DNA was found on
Rinso detergent solution. The time required for the formation of DNA in each
solution is clearly different. For Bu krim detergent powder, the average time
needed to form DNA is faster than at the Surf detergent solution.
When viewed as a whole, the use of pear fruit as a source of DNA
produces DNA precipitate more than the use of tomatoes as the source of DNA.
3.2 Discussion
DNA isolation basically can be done by using various sources of DNA
which can be obtained from animals and plants. DNA obtained in the
observation is in the form of DNA strands which are so fine that looks like a

2. very soft white mist. Efforts for removing the DNA from the cell were done by
destroying cell wall and cell membrane and the nuclear membrane.
The first step is to lyse or break open the cell. This can be done by
grinding a piece of tissue in a blender. Plasma membrane or cell membrane is
composed of fat and protein molecules. Fat molecule composed of two layers,
located at the center of the membrane. The functions of the cell membrane are
protecting the cell contents, which serves to maintain the cell contents and to
control molecules traffic. Cell membranes in all organisms can suffer damage
caused by the influence of chemical compounds. Chemical compounds that can
damage the membrane or cell wall are lysozyme that can affect the polymeric
compound so that cell stiffness can no longer be maintained. In the process of
DNA isolation, detergent serves as a destroyer of the cell membrane. Detergent
contains sodium dodecyl sulphate (SDS), which can remove lipid molecules in
the cell membrane so that the membrane structure will be damaged and lyse the
contents of the cells (Jamilah, 2005).
In the cell nucleus, DNA is present in a complex structure called
chromatin. Chromatin is composed of a large number of proteins and nucleic
acids known as deoxyribonucleic acid (DNA). Chromosomal protein that binds
to DNA is simply divided into two main classes of chromosomal protein
histone and non-histone. With the bond between the DNA with the protein, the
chromatin is highly soluble in water since histones and non-histone protein is
soluble in water. Therefore, the isolation of DNA uses salt in order to separate
the DNA with histones and non-histone proteins as well as concentrating the

3. DNA. This can be happened because the Na+ ions contained by salt capable of
forming a bond with the negative pole of the DNA phosphate bond. When the
Na+ ions bind to phosphate, the DNA is assembled.
The addition of alcohol to the solution intends to do the precipitation
because DNA is not soluble in alcohol, so that DNA which has been
accumulated was able to separate from the solution and formed layers of
identifiable constituent elements.

4. DAFTAR PUSTAKA
Yulia, Floweriza. 2012. DNA buah. http://flowerizayulia.blogspot.com/2012/
01/laporan-dna-buah.html. Diakses tanggal 28 Oktober 2012.
Rasyid, Kharisma Aditya. 2011. STRUKTUR DAN FUNGSI MEMBRAN SEL.
http://khaditoya.blog.unsoed.ac.id/2011/10/28/struktur-dan-fungsi-
membran-sel/. Diakses tanggal 28 Oktober 2012.
DNA extraction. http://en.wikipedia.org/wiki/DNA_extraction. Diakses tanggal
28 Oktober 2012.
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Robbie. 2008. http://answers.yahoo.com/question/index?qid=20080710142651
AABl7aB. Diakses tanggal 28 Oktober 2012.