Extraction of Soluble and Bound .ALPHA.-Glucosidases from Banana Pulp.

Abstract

a-Glucosidase (EC 3.2.1.20) participates in complete starch breakdown in plant tissues by hydrolyzing the oligosaccharides or maltose produced by a-or /?-amylases.1>2) Wehave previously reported that acid and neutral a-glucosidases (AAG and NAG, respectively) and their multiple forms were present in banana pulp.3) We also observed that the apparent p/s of these enzymeswere changeable during the ripening of bananas.3) These results, however,cast doubts on our choice of bananasamplesas the starting material for purifying a-glucosidase, which is our final goal.

Inhibition of β-amylase activity, starch degradation and sucrose formation by indole-3-acetic acid during banana ripening

“…However, there is evidence that the amylolytic pathway should not be ruled out. The increase in several amylolytic enzymes, such as a-amylase, b-amylase, and a-glucosidases during ripening (Garcia and Lajolo 1988;Kitazato et al 1991), and also the large proportion of amylopectin in banana starch granules (Mota et al 2000) point to a coordinated action of both amylolytic and phosphorolytic starch degradation. Another piece of evidence to support this amylolytic pathway would be the presence of a-amylase, which is recognized as the only enzyme that can attack native starch granules (Hallett et al 1995;Sivak and Preiss 1998).…”