Generally we state instrument limit of detection for this type of assay as the U/mL value achieved when what we consider the 'minimum absorbance' is achieved (usually 0.02 Absorbance Units) under the standard assay format. The figures for limit of detection of K-CERA are shown below:
Malt flour: 0.5g extracted in 100mL and further diluted 1:20 for assay = 7.48U/g (pH 5.4, 40˚C, 10 min)
Microbial (powder): 1g extracted in 50mL and further diluted 1:10 for assay = 0.94U/g (pH 5.4 / 6.5, 40˚C, 10 min)
Microbial (liquid): 1mL diluted in 50mL and further diluted 1:10 for assay = 0.94U/mL (pH 5.4 /6.5, 40˚C, 10 min)
Wheat and barley flour: 3g extracted in 20mL with no further dilution for assay = 0.00623U/g (pH 5.4, 40˚C, 20 min)
It is possible to increase the sensitivity of the assay by increasing the incubation time and or the sample volume.