NOVELTY - Comamonas testosteroni strain is cultured in sloped solid culture medium for 12-18 hours and preserved. Then, substrate solution is added into flask, the substrate solution is sterilized and cooled. The substrate is diethyl phthalate. The obtained bacterial strain is transferred into substrate solution to obtain degrading solution. The degrading solution is vibrated, catalyzed and degraded. Then, the degrading rate of substrate and degraded product of substrate is detected.    USE - Degradation of polyethylene terephathalate.    DETAILED DESCRIPTION - Comamonas testosteroni strain is cultured at 30-37 degrees C in sloped solid culture medium for 12-18 hours and preserved at 4 degrees C. The solid culture medium contains 3g/L of monopotassium phosphate, 7g/L of disodium hydrogen phosphate, 1g/L of ammonium chloride, 5g/L of sodium chloride, 0.25g/L of magnesium sulfate, 18g/L of agar powder and 3g/L of substrate. Then, substrate solution is added into flask, the substrate solution is sterilized at 120 degrees C for 25 minutes and cooled. The substrate is diethyl phthalate. The obtained bacterial strain is transferred into substrate solution to obtain degrading solution. The degrading solution is vibrated at 37 degrees C, catalyzed and degraded. Then, the degrading rate of substrate is detected by taking a bottle of degrading solution out every 12 hours, inactivating the degrading solution at 95 degrees C for 5 minutes, cooling the degrading solution, adding 10 ml of n-hexane, uniformly vibrating the degrading solution, extracting insoluble substrate, defoaming, collecting liquid in n-hexane layer, diluting the liquid by n-hexane to 50-250 times, scanning by 400-190 nm long wave through an ultraviolet spectrophotometer and observing the change of substrate content according to absorptive peak at 240nm. Then, degraded product of substrate is detected by taking a bottle of degrading solution out every 12 hours, inactivating the degrading solution at 95 degrees C for 5 minutes, cooling the degrading solution, adding 10 ml of n-hexane, uniformly vibrating the degrading solution, extracting insoluble substrate, defoaming the degrading solution, collecting liquid in water layer, diluting the liquid by water to 50-250 times, scanning by 400-190nm long wave through an ultraviolet spectrophotometer and observing the change of diethyl phthalate content according to the height of absorptive peak at 240 nm. The substrate is completely degraded when absorptive peak is not absorbed in n-hexane layer and water layer.