Enzymatic Treatment of Organics in Tannery Effluent

This study investigates the ability of enzyme technology to treat organics in tannery effluent. Three bacteria strains were tested for their ability to remove organic matter in tannery effluent, and the active sites of the respective enzymes were determined. Subsequently, the active enzymes that remove organics were extracted from the three strains and tested for the optimal activity of tannery effluent under different temperatures, pHs, concentrations, and incubation times. The results demonstrated that all three strains (Bacillus subtilis, Bacillus cereus, and Bacillus fusiformis) are able to remove organics in the tannery effluent. The active enzyme of Bacillus subtilis is an intracellular enzyme, whereas the active enzymes for Bacillus cereus and Bacillus spindle are extracellular enzymes. At pH 7, Bacillus subtilis and Bacillus cereus can, respectively, remove 37.79% and 35.34% of the organic waste in tannery water at 40°C. Bacillus fusiformis can remove up to 49.60% of the organic waste when the incubation time is extended to 8 h. The enzyme concentration is fixed at 2 × 10–4g for all conditions. In this study, enzyme technology provides a novel approach for organic removal in a tannery effluent treatment, and it has the potential to be combined with other methods in the future.