Actinobacterial peroxidase-mediated biodeterioration of hazardous explosive, 2, 4, 6, trinitrophenol by in silico and in vitro approaches.

Explosives are perilous and noxious to aquatic biota disrupting their endocrinal systems. Supplementarily, they exhibit carcinogenic, teratogenic and mutagenic effects on humans and animals. Henceforth, the current study has been targeted to biotransform the explosive, 2, 4, 6 trinitrophenol (TNP) by wetland peroxidase from Streptomyces coelicolor. A total peroxidase yield of 20,779 mg/l with 51.6 folds of purification was observed. In silico molecular docking cum in vitro appraisals were accomplished to assess binding energy and interacting binding site residues of peroxidase and TNP complex. TNP required a minimal binding energy of-6.91 kJ/mol and was subjected to biodeterioration (89.73%) by peroxidase in purified form, with 45 kDa and a similarity score of 34 by MASCOT protein analysis. Moreover, the peroxidase activity was confirmed with Zymogram analysis. Characterization of peroxidase revealed that optimum values of pH and temperature as 6 and 40 °C, respectively, with their corresponding stability varying from 3.5 to 7. Interestingly, the kinetic parameters such as Km and Vmax on 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and H2O2 were 19.27 µm and 0.41 µm/min; 21.4 µm and 0.1 µm/min, respectively. Among the diverse substrates, chemicals and trace elements, ABTS (40 mM), citric acid (5 mM) and Fe2+ (5 mM) displayed the highest peroxidase activity. Computational docking and in vitro results were corroborative and UV-Vis spectroscopy, HPLC, FTIR and GC-MS indicated the presence of simple metabolites of TNP such as nitrophenols and benzoquinone, showcasing the efficacy of S. coelicolor peroxidase to biotransform TNP. Henceforth, the current study offers a promising channel for biological treatment of explosive munitions, establishing a sustainable green earth.

Bioprospecting of novel peroxidase from Streptomyces coelicolor strain SPR7 for carcinogenic azo dyes decolorization.

Peroxidase (POX) is a heme-containing oxidoreductase, its voluminous immuno-diagnostic and bioremediatory intuitions have incited optimization and large scale-generation from novel microbial repertoires. Azo dyes are the most detrimental classes of synthetic dyes and they are the common ecotoxic industrial pollutants in wastewater. In addition, azo dyes are refractory to degradation owing to their chemical nature, comprising of azoic linkages, amino moieties with recalcitrant traits. Moreover, they are major carcinogenic and mutagenic on humans and animals, whereby emphasizing the need for decolorization. In the present study, a novel POX from Streptomyces coelicolor strain SPR7 was investigated for the deterioration of ecotoxic dyestuffs. The initial medium component screening for POX production was achieved using, One Factor at a Time and Placket-Burman methodologies with starch, casein and temperature as essential parameters. In auxiliary, Response Surface Methodology (RSM) was recruited and followed by model validation using Back propagation algorithm (BPA). RSM-BPA composite approach prophesied that combination of starch, casein, and temperature at optimal values 2.5%, 0.035% and 35 °C respectively, has resulted in 7 folds enhancement of POX outturn (2.52 U/mL) compared to the unoptimized media (0.36 U/mL). The concentrated enzyme decolorized 75.4% and 90% of the two azo dyes with lignin (10 mM), respectively. Hence, this investigation confirms the potentiality of mangrove actinomycete derived POX for elimination of noxious azo dyes to overcome their carcinogenic, mutagenic and teratogenic effects on humans and aquatic organisms.

Unravelling the emerging carcinogenic contaminants from industrial waste water for prospective remediation by electrocoagulation - A review.

The need of the hour relies on finding new but sustainable ways to curb rising pollution levels. The accelerated levels of urbanization and increase in population deplete the finite resources essential for human sustenance. In this aspect, water is one of the non-renewable sources that is running out very fast and is polluted drastically day by day. One way of tackling the problem is to reduce the pollution levels by decreasing the usage of chemicals in the process, and the other is to find ways to reuse or reduce the contaminants in the effluent by treatment methods. Most of the available water recycling or treatment methods are not sustainable. Some of them even use toxic chemicals in the processing steps. Treatment of organic wastes from industries is a challenging task as they are hard to remove. Electrocoagulation is one of the emerging water treatment technologies that is highly sustainable and has a comparatively cheaper operating cost. Being a broad-spectrum treatment process, it is suitable for treating the most common water pollutants ranging from oils, bacteria, heavy metals, and others. The process is also straightforward, where electrical current is used to coagulate the contaminates. The presence of carcinogens in these waste water increases the need for its treatment towards further use. The present investigation is made as an extensive analysis of the emerging carcinogens and their various sources from process industries, especially in the form of organic waste and their removal by electrocoagulation and its coupled techniques. The paper also aims to ascertain why the electrocoagulation technique may be a better alternative compared with other methods for the removal of carcinogens in organic wastewater, an analysis which has not been explored before.

Distillery industrial wastewater(DIW) treatment by the combination of sono(US), photo(UV) and electrocoagulation(EC) process.

The color and Chemical Oxygen Demand (COD) reduction in distillery industrial effluent (DIW) was investigated utilizing photo (UV), sono (US), electrocoagulation (EC), UV + US, UV + EC, US + EC, and US + UV + EC technologies. The empirical study demonstrated that the UV + US + EC process removed almost 100% of color and 95.63% of COD from DIW while consuming around 6.97 kWh m-3 of electrical energy at the current density of 0.175 A dm-2, COD of 3600 mg L-1, UV power of 32 W, US power of 100 W, electrode pairings of Fe/Fe, inter-electrode distance of 0.75 cm, pH of 7, and reaction time of 4 h, respectively. The values found were much greater than those produced using UV, US, EC, UV + US, UV + EC, and US + EC methods. The influence of various control variables such as treatment time (1-5 h), current density (0.075-2.0 A dm-2), COD (1800-6000 mg L-1), inter-electrode distance (0.75-3.0 cm), electrode pairings (Fe/Fe, Fe/Al, Al/Fe, Al/Al), UV (8-32 W), and US (20-100 W) on the color and COD reduction were investigated to determine the optimum operating conditions. It was observed that, an increase in treatment time, current density, UV and US power, decrease in the COD, and inter-electrode distance with Fe/Fe electrode combination improved the COD removal efficiency. The UV and US + EC processes' synergy index was investigated and reported. The results showed that, the US + UV + EC treatment combination was effective in treating industrial effluent and wastewater.

Advances in bioremediation of emerging contaminants from industrial wastewater by oxidoreductase enzymes.

The bioremediation of emerging recalcitrant pollutants in wastewater via enzyme biotechnology has been evolving as cost-effective with an input of low-energy technological approach. However, the enzyme based bioremediation technology is still not fully developed at a commercial level. The oxidoreductases being the domineering biocatalysts are promising candidates for wastewater treatments. Henceforth, comprehending their global market and biotransformation efficacy is mandatory for establishing these techno-economic bio-enzymes in commercial scale. The biocatalytic strategy can be established as a combinatorial approach with existing treatment technology to achieve towering bioremediation and effective removal of emerging pollutants from wastewater. This review provides a novel insight on the toxicological xenobiotics released from industries such as paper and pulps, soap and detergents, pharmaceuticals, textiles, pesticides, explosives and aptitude of peroxidases, nitroreductase and cellobiose dehydrogenase in their bio-based treatment. Moreover, the review comprehensively covers environmental relevance of wastewater pollution and the critical challenges based on remediation achieved through biocatalysts for future prospectives.