RESUMEN
It designs a way that can easily screen high-pyruvate-producing strain.It is a intelligently selected method which can highly improve the efficiency of strain screening.The principle can be described as the following:On the CaCO-3 medium,a transparent ring can be exhibited based on the reaction of PYR produced by the strain and CaCO-3 in the medium for pyruvate-calcium is a kind of soluble substance,it is obviously that the high-pyruvate-producing strain has a bigger dimension of the transparent ring.On the other hand,color reaction between TTC and ADH indicate the enzyme activities which have a proportional relation with color,our object strain is a weak-ADH-enzyme-activities type with a weak metabolic flux from PYR to alcohol.So the white color strain may be the right choice.