Sustainable bioremediation approach to treat the sago industry effluents and evaluate the possibility of yielded biomass as a single cell protein (SCP) using cyanide tolerant Streptomyces tritici D5.

This sustainable approach was performed to evaluate the bioremediation potential of cyanide resistant bacterial species on sago industry effluents and assess the possibility of using the yielded biomass as single cell protein (SCP). The predominant cyanide tolerant bacterium enumerated from muddy soil was identified as Streptomyces tritici D5 through 16S rRNA sequencing. The identified S. tritici D5 strains showed excellent resistant and degradation potential at 100 mM concentration of potassium cyanide. Furthermore, the physicochemical properties analysis of sago industry effluents results revealed that the most of the parameters were crossing the permissible limits of Pollution control board of India. The bioremediation process was performed at various temperatures at 25 °C, 35 °C, and 45 °C for a period of 30 days of continuous bioremediation process with the aid of an aerator. Surprisingly, the best organic pollutant reduction was found at 35 °C and 45 °C, with 25 °C following close behind. Remarkably, the dissolved oxygen (DO) level was gradually increased from 2.24 to 12.04 mg L-1 at 35 °C in 30 days of the remediation process. The pH and ammonia were also significantly increased during the bioremediation process in 30 days of treatment. Similarly, at 35 °C of bioremediation process the S. tritici D5 yielded maximum dried biomass (6.9 g L-1) with the total crude protein (SCP) as 4.8 g L-1 (69.56%) in 30 days of growth. These findings stated that S. tritici D5 can treat sago industry effluents and that the biomass produced may be considered SCP after some in-vitro and in-vivo analyses.

Bioremediation competence of Aspergillus flavus DDN on pond water contaminated by mining activities.

This research was performed to evaluate the possibilities of reducing the physicochemical properties of polluted pond water situated around the magnesite mine tailing through indigenous metal tolerant fungi. The physicochemical analysis results revealed that most of the physicochemical properties of pond water sample were crossing the permissible limits. From the muddy pond soil sample, Aspergillus flavus DDN was identified (through molecular characterization) as predominant metal tolerant fungal strain and it showed resistance to Cr(VI), Pb(II), Zn(II), Cd(II), and Mg(IV) up to 1000 µg mL-1 concentrations. This strain also effectively reduced (through biosorption) these metals in a short duration of the bioremediation process. In a lab-scale bioremediation study, the A. flavus DDN significantly reduced most of the physicochemical parameters crossing the permissible limit in polluted pond water in the presence of FM1 minimal media in 10 days of incubation. The dissolved oxygen level was significantly increased up to 74.91% from 5.86 ± 0.39 to 10.25 ± 0.95 in 10 days of treatment. The metal reduction and other physicochemical properties reduction were directly related to the biomass of A. flavus DDN. These findings suggest that A. flavus DDN can remove pollutants from magnesite mine tailing polluted pond water because elevated fungal biomass resulted in the highest percentage of pollutant reduction from the sample.