Fructan- and sucrose-hydrolyzing activity was extracted from plants of
Lolium rigidum Gaudin. Sucrose-hydrolyzing activity varied 30-fold be
tween different plant parts and parts of different ages. In contrast,
fructan-hydrolyzing activity only varied two-fold. At least four beta-
fructofuranosidase activities were partially purified from mature vege
tative tissues of Lolium rigidum. The beta-fructofuranosidases were ch
aracterized by their different elution patterns on various chromatogra
phic media and their relative rates of hydrolysis of sucrose and fruct
an extracted from different sources. Fructan-hydrolyzing activities we
re partially purified that hydrolyzed fructan containing predominantly
2-1 glycosidic linkages relatively more rapidly than fructan containi
ng predominantly 2-6 glycosidic linkages. beta-fructofuranosidases tha
t were relatively more active against fructan than sucrose when compar
ed with activity present in the crude extract, were inhibited by sucro
se. It is concluded that it is necessary to use appropriate fructan su
bstrates and to consider the possible involvement of all beta-fructofu
ranosidase activities in hydrolysis of fructans in grasses.