Eco-friendly degradation of reactive red 195, reactive blue 214, and reactive yellow 145 by Klebsiella pneumoniae MW815592 isolated from textile waste

Acidified groundnut cake for enhanced bio adsorption of anionic textile dye Reactive Red 195

This study focuses on the improvement of bioremediation of textile dye Reactive Red 195 using agro-industrial waste, groundnut oil cake (GNOC) obtained after oil-pressing. The treatment of GNOC with 1 N H2SO4 had resulted in physiochemical changes on the insoluble porous adsorbent, which improved their adsorption efficiency. The dye removal efficiency increased from 55% to 94% on acidification of GNOC. The raw groundnut oil cake (RGNOC) and acid-treated groundnut oil cake (AGNOC) were characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction, and zeta potential. The rate and efficiency of dye adsorption were examined using adsorption kinetics and isotherm models. The results confirm that acid-treated GNOC eliminates impurities, alter the surface functional groups, and significantly increase porous surface areas of RGNOC. The investigation of key factors such as contact time, initial concentration of dye, static/agitation impact, particle size, and adsorbent dose had significantly influenced adsorption capacity of GNOC. Adsorption of dye fits best into the Langmuir model and equilibrium data of dye on AGNOC was explained by psuedo-second-order reaction with maximum adsorption capacity of 12.65 mg/g. This emphasis AGNOC has a very excellent potential to remove the textile dye Reactive Red dye from industrial effluent.

Systematic screening strategy for fungal laccase activity of endophytes from Otoba gracilipes with bioremediation potential

Fungal laccases are promising for biotechnological applications, including bioremediation and dye biotransformation, due to their high redox potential and broad substrate specificity. However, current bioprospecting methods for identifying laccase-producing fungi can be challenging and time-consuming. For early detection, it was developed a three-step, multi-criteria weighting system that evaluates fungal strains based on: First, the biotransformation capacity of three dyes (i.e., Congo red, brilliant blue G-250, and malachite green), at three different pH values, and with a relative weighting supported for the redox potential of each colorant. The relative decolorization coefficient (RDC), used as th2e first classification criterion, expressed their potential performance. Second, under the same conditions, laccase activity was estimated by observing the different degrees of oxidation of a given substrate. The selection criterion was the relative oxidation coefficient (ROC). Finally, laccase activity was quantified in submerged fermentations using three inducers (i.e., loofah sponge, Tween 80, and veratyl alcohol). This multicriteria screening strategy evaluated sixteen isolated endophytic fungal strains from Otoba gracilipes. The system identified Beltraniopsis sp. ET-17 (at pH values of 5.00 and 5.50) as a promising strain for dye biotransformation, and Phlebia floridensis as the best laccase producer, achieving a high activity of 116 μmol min-1 L-1 with loofah sponge as an inducer. In-vitro testing confirmed the efficacy of P. floridensis, with 53.61 % decolorization of a dye mixture (brilliant blue-Congo red. ratio 1:1) after 15 days of incubation. Thus, with the proposed screening strategy it was possible to highlight two species of interest at an early bioprospecting stage on a Colombian native tree poorly explored.

Evaluation of Bioremediation Potentiality of Bacillus mojavensis Isolated from Wastewater for the Elimination of Reactive Yellow 145 and Methyl Orange

Textile industry waste has become one of the largest polluters in the world. In recent years, there has been a growing awareness of the need for sustainable and eco-friendly practices for the treatment of dye-laden effluents. Overall, this study highlights the potential of bioremediation as a sustainable solution for wastewater treatment. The Bacillus mojavensis isolated from wastewater and identified using 16S rRNA degraded reactive yellow 145 and methyl orange in 36 h of incubation, this decolorization was affected by pH, temperature, dye concentration, glucose concentration, source of nitrogen, type of dye, and agitation. Our study found that the optimal conditions for total decolorization of dyes were achieved by incubating B. mojavensis at 46 °C, pH 9, with 1 g/L of glucose and 2 g/L of peptone. The azoreductase activity, FT-IR analysis, and UV-visible spectrum before and after total decolorization indicated that it was a dye degradation rather than biosorption in surface Celle. In addition, the study of phytotoxicity show the metabolites of degradation are not phytotoxic in Lens esculenta seeds. In conclusion, our results suggest the use of this bacterium as an environmentally friendly and also cost-effective method, making it an attractive option for industries looking to reduce their environmental impact.