I have been doing photometric studies of amylase degradation of amylose,
and gotten just OK results using cornstarch (Kingsford's). By "OK"
results I refer to fact that my data curve does only an OK job of holding
to the theoretical Michaelis Menten curve. (The data seems to keep
drifting up.)
When I switched to using arrowroot starch, the match between data and
theory is excellent! Since cornstarch is actually a mixture of amylose
and amylopectin, the amylase has two different substrates. Hence, I
assume my curve is actually the sum of two curves, amylose degrading two
substrates.
my question: Why should arrowroot starch give results that are so much
better? Is arrowroot starch pure amylase?
Bruce Ratcliffe, a puzzled high school science teacher in Fresno
(BruceRat at AOL.COM)