Produção de enzimas coagulantes do leite por Aspergillus flavo furcatis em resíduos da agroindústria

Abstract

Six strains of Aspergillus flavo furcatis were screened to investigate milk-clotting enzyme production by fermentation in natural liquid medium. The growth media comprised extracts of Cupuaçu Exocarp+Rice Bran [10% or 20% (v/v) CE+RB] and Açai Waste+Rice Bran [10% or 20% (v/v) AW+RB] with or without supplementation 0.1% (w/v) of yeast extract and 0.5% (w/v) gelatin. Significant values of milk-clotting activity were determined by A. flavo furcatis DPUA 1461 and DPUA 1608, in the standard and natural media, respectively. According to criteria of clot and whey formations, 8.3% of the samples tested were classified as strong coagulation, 41.70% showed weak coagulation and in 50% wasn’t observed milk coagulation. Milk-clotting proteases of A. flavo furcatis DPUA 1608 were inhibited by pepstatin (94.72%) and moderately inhibited by the others metal ions tested. The optimal action was at 40 °C and pH 7.0.