Isolation, Identification of Bacillus Thuringiensis/ Cereus and Its Enhancement on Protein Wastewater Treatment by Rhodobacter Sphaeroides

Abstract

In order to enhance the degrading protein capability of purple non-sulfur bacteria (PNSB), an effective strain, L2, was used to co-culture with Rhodobacter sphaeroides ATCC17023. The effects of added strain on protein removal of R. sphaeroides were investigated. Results showed that strain L2, being identified as Bacillus thuringiensis / cereus , had a high potential for producing protease with a production of 295 U/mL.The optimal B. thuringiensis / cereus (40 μL) could significantly increase protein degradation of R. sphaeroides . Protein removal and biomass production were improved by 483% and 67%, respectively. R. sphaeroides /total biomass production was more than 95%. Theoretical analysis revealed that R. sphaeroides syntrophically interacted with B. thuringiensis / cereus . Protein degradation of B. thuringiensis / cereus provided small molecule substrates (VFAs) for R. sphaeroides growth and cells materials synthesis.