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Table 1 Effect of gamma rays on the survival of super Koji (A. oryzae) grown on Potato Dextrose Agar (PDA) plates in the presence of 0.4% Triton X-100

From: Random mutagenesis of super Koji (Aspergillus oryzae): improvement in production and thermal stability of α-amylases for maltose syrup production

Dose (kGy) CFU ml-1 Log CFU ml-1 % Survival % Kill Log Kill
Parent Koji 3,450,000 6.538 100
0.6 3,167 3.501 0.092 99.908 3.037
0.8 2,666 3.426 0.077 99.923 3.112
1.0 1,167 3.067 0.034 99.966 3.471
1.2 500 2.699 0.014 99.986 3.839
1.4 167 2.223 0.004 99.996 4.315
  1. Where: CFU ml-1 is an average of triplicate values
  2. CFU ml-1 = Viable count ml-1 of sample spread on the plate × Dilution factor
  3. % Survival = CFU ml-1 of irradiated÷ CFU ml-1 of control ×100
  4. % Kill = 100 - % Survival
  5. Log kill = log CFU ml-1 of control - log CFU ml-1 of irradiated fungus
  6. Gamma source= Cesium 137