Utilization Technology Development For E. Coli BL21/pET28a-cr Fermentation Wastewater Resource

E.coli BL21/pET28a-cr can catalyze the synthesis of atorvastatin key chiral intermediate t-Butyl-6-cyano-?3R,5R?-dihydroxylhexanoate,but the process of the E.coli BL21/pET28a-cr preparation will produce a lot of wastewater which include kanamycin.Therefore,it is significant to develop a technology of reuse wastewater.This paper had established a method to detect the concentration of kanamycin in wastewater.We chosen the resin which can remove the kanamycin in wastewater,and studied on the thermodynamics and kinetics of kanamycin adsorption on resin HZD-2.Furthermore,we reused the wastewater to ferment validamycin.First,a simple and sensitive pre-column derivatization liquid chromatographic method was developed for trace determination of kanamycin in fermentation wastewater by using phenyl isocyanate as a derivatization reagent.The experimental condition for derivatization and separation of kanamycin derivatives were optimized and validated.The correlation coefficient was greater than 0.999 over the range between 1and 250 mg/L.The detection limit was as low as 1 mg/L.Recoveries ranging from 99.5 to 107.1%were obtained.Phenyl isocyanate groups were attached to corresponding amino groups of aminoglycoside and their molecular mass was confirmed by liquid chromatography-electrospray ionization-mass spectrometry?LS-ESI-MS?.The kanamycin in wastewater detected by the method is 41.9 mg/L.Second,we developed a wastewater treatment process.Among eleven macroporous resin adsorbents tested,the resin HZD-2 have the best adsorption and desorption performance.Then the experimental condition for adsorption of kanamycin were optimized and validated.The dosage of HZD-2 and the absorbent temperature were confirmed as 30g/L and 30°C,respectively.Then we chosen 2%?v/v?NH₄OH as desorption agent,whose desorption rate was 83.9%.The statics equilibrium adsorption data fitted well with the Langmuir equation,and the adsorption kinetic followed the pseudo-second order model.Finally,treated wastewater was supplemented into media in a replacement of 25%tap water.Results indicated that the validamycim titer produced by wastewater medium was 92.1%,with validamycim titer of tap water medium was recored as 100%,reliazing the resource utilization of fermentation wastewater.