Total genomic DNA was isolated from flesh kiwifruit
tissue according to a modified procedure.[16]
The extraction technique was divided into three
steps: mechanical destruction of cells (plant tissue
and cell breakage), chemical destruction of biological
membranes, and precipitation of DNA extracted.
The samples were prepared starting with 30 g of
fruit. Forty milliliters of NaCl 1M and 2mL of liquid
detergent containing SDS (sodium dodecyl sulfate
[Sigma Chemical Co., UK]) were added over the
pulp of the fruit. The solution was gently stirred
with a glass rod to mix. The mixture was filtered
to separate the nucleic acid from the remains of
the cellular membranes. To a quantity of 10 mL of
resulting solution an equal volume of ice-cold
ethanol was added with precaution, avoiding the
mix of the two components. Because the alcohol
is less dense than water, it forms a layer of ethanol
on top of the DNA solution. The DNA precipitates
at the interface between the alcohol and DNA
solution.