Adsorption/desorption characteristics, separation and purification of phenazine-1-carboxylic acid from fermentation extract by macroporous adsorbing resins

BACKGROUND Pseudomonas chlororaphis GP72 is a biocontrol strain with great capacity to produce a wide range of secondary metabolites including phenazine derivatives. Phenazine-1-carboxylic acid (PCA) is an environmentally friendly antibiotic with broad-spectrum biological and pharmaceutical activities. Many studies have been focused on engineering high-yielding strains and optimizing fermentation bioprocesses to enhance PCA biosynthesis. However, the separation and purification of PCA in biotechnological production remain to be addressed. In this context, the present work intended to develop a simple and proficient technique for the separation and purification of PCA from the fermentation broth of engineered P. chlororaphis GP72AN. RESULTS Five macroporous adsorbents with different physicochemical characteristics were screened to present their PCA separation potential. Among them, HP-20 resin was found highly suitable based on its promising adsorption and desorption performance in a static batch process. Langmuir and Freundlich isotherms deciphered the solute binding affinity towards HP-20 adsorbent at varying temperatures, and the experimental data fitted best to the Langmuir isotherm model. The column-assisted dynamic adsorption–desorption trials were executed to optimize the functional parameters for PCA separation. Under standardized separating conditions, the average adsorption capacity and desorption ratio of PCA were 24.4 ± 1.5 mg g −1 dry resin and 86.5 ± 1.3%, respectively. After treatment with HP-20 resin, PCA contents in the product were considerably increased with a recovery yield of 78.4 ± 2.4%. CONCLUSION In conclusion, the method proposed herein achieved effective separation and purification of PCA by applying HP-20 resin. The results obtained also suggest an encouraging basis for scale-up preparation of PCA and other high-value phenazine compounds of industrial interests. © 2018 Society of Chemical Industry