RELATIONSHIP BETWEEN CARBON SOURCE, PRODUCTION AND PATTERN ACTION OF ALPHA-AMILASE FROM RHIZOPUS SP

This paper discusses the inducer effect of corn soluble starch and the individual components (amylose and amylopectin) from corn and potatoe s starch for alpha-amylase production by a strain of Rhizopus sp. The following decreasing order in the enzyme production was obtained: corn amylose > potatoes amylose > corn amylopectin > potatoes amylopectin > starch > maltose, coinciding with the ability of the enzyme to relea se reducing units, except the soluble starch that was more softly hydr olysed. However, when the enzyme action was measured by the iodine bin ding method, an inverse order of enzyme activity was obtained, that is : amylopectins > starch > amylosis. The results suggest that: a) branc hed structures in substrate affect the enzyme production; b) corn amyl ose and corn amylopectin are better inducers than their respectives ho mologous from potatoes; c) cc-amylase from Rhizopus sp has different a ction patterns on substrates with straight or branched chains: from th e former, it removes only reducing units with lower molecular weight ( G1-G3); from the latter it also removes oligosaccharides with higher m olecular weight (G5-G6).