Increasing the scale of peroxidase production by Streptomyces sp. strain BSII#1

Abstract

Aims To optimize peroxidase production by Streptomyces sp. strain BSII#1, up to 3 l culture volumes.

Methods and Results Peroxidase production by Streptomyces sp. strain BSII#1 was optimized in terms of production temperature and pH and the use of lignin-based model chemical inducers. The highest peroxidase activity (1·30 ± 0·04 U ml−1) in 10 ml culture volume was achieved in a complex production medium (pH 8·0) at 37°C in the presence of 0·1 mmol l−1 veratryl alcohol, which was greater than those reported previously. Scale-up to 100 and 400 ml culture volumes resulted in decreased peroxidase production (0·53 ± 0·10 and 0·26 ± 0·08 U ml−1, respectively). However, increased aeration improved peroxidase production with the highest production achieved using an airlift bioreactor (4·76 ± 0·46 U ml−1 in 3 l culture volume).

Conclusions Veratryl alcohol (0·1 mmol l−1) is an effective inducer of peroxidase production by Streptomyces sp. strain BSII#1. However, improved aeration increased peroxidase production in larger volumes without the use of an inducer, surpassing induced yields in an optimized small-scale process.

Significance and Impact of the Study Only a limited number of reports in literature have focused on the up-scaling of bacterial peroxidase production. There remains opportunity for feasible large-scale production of bacterial peroxidases with potentially novel biocatalytic properties.