ACTIVITIES OF α-AMYLASE AND ITS INHIBITORS IS AFFECTED BY NITROGEN AND SULFUR CONTENT IN BARLEY SEED

ARIAS GUILLERMINA; CODÓ PATRICIA; PETON ANDRÉS; PRYSTUPA PABLO; PAGANO EDUARDO

Rosario

Congreso; L Reunión SAIB 2014; 2014

Sociedad Argentina de Investigación Bioquímica

Plant seeds have different proteinaceous α-amylase inhibitors that participate in both the control of the endogenous α-amylase and the protection of seeds from pests. Barley α-amylase/subtilisin inhibitor (BASI) is synthesized during grain filling and inhibits the major α-amylase isozyme synthesized during germination (AMY2). It is known that mineral composition of the grain may affect the content of various proteins, whether they are structural, storage or metabolic proteins. The aim of this work was to evaluate the effect of nitrogen (N) and sulfur (S) grain content on the activities of α-amylase and its inhibitors. Seeds with different chemical composition were placed under germination conditions and α-amylase activity during germination and its enzymatic inhibition were measured up to 48 h after imbibition. The enzyme activity increased in the 48 hours following imbibition and was highest in seeds with greater content of N. Higher nutrient concentration (either N or S) resulted in lower inhibitor activity. These results indicate that chemical composition of the seeds could affect germination by regulating both α-amylase activity and that of its inhibitors.