Bread spoilage fungi as creators of α amylase using two types of wheat flour

Abstract

Fungal spoilage of bread can be a great problem; however, it can be explored as a producer of enzymes. The fungi were isolated from breads, and their activity for α-amylase production was planned. The results identified nine fungi on spoiled breads. Aspergillus fumigatus occurred with 85% frequency, followed by other isolates. Starch yeast (SY), white flour (WF), and black flour (BF) were applied as substrates for α-amylase activity using fungal isolates. The SY was the best, followed by WF and BF for α-amylase activity. Using SY, A. niger showed the greatest potency for α-amylase (7.67 U/mL) unlike Monilia sitophila, which reflected low α-amylase activity (2.69 U/mL). Using WF, A. fumigatus reflected high amylase activity (5.76 U/mL) while A. niger, A. terreus, and Penicillium expansum showed less activity (5.12 U/mL, 4.41 U/mL, and 3.56 U/mL, respectively). The temperature 30 °C and pH 6 were the optimum for α-amylase activity by A. niger, A. fumigatus, and P. chrysogenum, using the three media, but α-amylase activity of A. fumigatus at 40 °C was higher than at 20 °C. At the ninth day of incubation, the maximum α-amylase activity was reported using SY, while at the twelfth day, maximum activity was reported using WF and BF.