| MadSci Network: General Biology |
The simple answer is that not all fruits are the same; extractable DNA can vary from fruit type to type, and even with the same fruit, it may vary from stage to stage. Even the same fruits at different stages of development will yield different amounts of extractable DNA. Some fruits are dry at maturity (acorn, bean pod); the cells are dead. So the amount of DNA would be very low.
Other fruits undergo a cellular dissolution as they reach maturity, so they would have more DNA at a younger stage. But other fruits may have more extractable DNA as they ripen because the cell walls are getting softer and the tissue easier to mash. Some fruits may differ in extractable DNA yield because of differences in pH or proteolytic enzymes (pineapple, papaya).
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