Application of oxygen uptake rate and response surface methodology for erythromycin production by Saccharopolyspora erythraea

Abstract

A process for efficient production of erythromycin by Saccharopolyspora erythraea using statistical designs and feeding strategy was developed. The critical nutrient components were selected in accordance with fractional factorial design and were further optimized via response surface methodology. Three significant components (ZnSO(4), citric acid threonine) were identified for the optimization study. The optimum levels of these significant variables were determined with Box-Behnken design, which were ZnSO(4) 0.039 g/l, citric acid 0.24 g/l and threonine 0.42 g/l, respectively. A novel feeding strategy based on oxygen uptake rate (OUR) measurement was developed successfully to increase the flux of erythromycin biosynthesis, in which the optimized nutrient components was fed in the 50 l stirred bioreactor when OUR began to decline at 46 h. The maximum erythromycin production reached 10,622 U/ml, which was 11.7% higher than the control in the same cultivation conditions. It was the first report to integrate physiological parameter OUR and statistical methods to optimize erythromycin production.

Biochemical parameters of Saccharopolyspora Erythraea during feeding ammonium sulphate in erythromycin biosynthesis phase

“…The concentration of total erythromycin pro duction was measured by the modified colorimetric method [14]. After removing the biomass and insolu ble ingredients, the fermentation broth was extracted with butyl acetate.…”

Real-time fluid dynamics investigation and physiological response for erythromycin fermentation scale-up from 50 L to 132 m3 fermenter

“…Its absorbance was measured at 498 nm with a spectrophotometer. To confirm the production of erythromycin, the fermentation broth samples at the end of fermentation were further bioassayed against Bacillus pumilus CMCC (B) 63202 using cylinder plate assay method (China Pharmacopoeia 2005) [6,7,21]. Rheological properties of the broth Rheological behavior of fermentation broth in 50 L and 132 m 3 fermenter was measured using a programmable rotating rheometer (DV-III Ultra, Brookfield) with the small sample adapter and proper spindle, which provided a defined geometry system for accurate viscosity measurements of small sample volumes at precise shear rates.…”

“…In our previous work, we found that OUR was very important for erythromycin biosynthesis [6,7]. However, how the bioreactor operating status interfering cell physiology was still unclear.…”

The dynamic regulation of nitrogen and phosphorus in the early phase of fermentation improves the erythromycin production by recombinant Saccharopolyspora erythraea strain

“…The erythromycin titer was measured by the modified colorimetric method [20]. The fermentation supernatant was collected after centrifugation and poured into the equal volume of K 2 CO 3 solution (0.35%).…”