Chromium removal and reduction in COD of tannery effluents

Tannery effluents are highly polluting and contain chromium and high COD and BOD. Alkalotolerant/alkalophilic actinomycetes NCIM 5080 and NCIM 5109 have been shown earlier to tolerate and accumulate chromium during growth also produce alkaline protease in presence of chromium ions. These properties of the isolates are suitable for treatment of tannery effluents which are alkaline and contain chromium and proteinaceous matter. Both the actinomycetes are able to grow in undiluted tannery effluents and remove chromium almost completely and reduce the COD by 70-80% during growth as well as by pregrown biomass.