The pollution of aquatic bodies by synthetic dyes is regarded as one of the most significant environmental issues, which has prompted greater research into effective and sustainable removal techniques. Even though there have been major efforts in the previous few decades, more study is still necessary to fully examine the long-term performance and usable applicability of adsorbents and different adsorption techniques for the removal of dye. In the present study, a brown marine macroalga Sargassum muticum was used as an effective and sustainable biosorbent for the crystal violet (CV) dye removal from aqueous solutions. The biosorbent was characterized by analysis of SEM, EDX, and FTIR. In order to evaluate the optimum conditions of CV biosorption, several parameters have been examined as a function of contact time, algal dose, initial concentration of CV, and pH. The maximum CV removal was obtained at 60 min contact time, 10 g/L algal dosage, 30 mg/L initial concentration of CV, and pH 6. The isothermal models of Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin are best explained the equilibrium data obtained. At the optimum conditions, the maximum biosorption capacity of the algal biomass achieved from the Langmuir model was 39.1 mg/g. The kinetic adsorption models were also better explained using the pseudo-second-order and Elovich model, and the effect of the boundary layer was indicated using the intraparticle diffusion model as well as the chemisorption-controlled biosorption process. Thermodynamically, the process of CV biosorption was shown to be random, spontaneous, and endothermic. Furthermore, the proposed mechanism of CV dye biosorption onto algal biomass is regulated by hydrogen bond formation, electrostatic interaction, and ion exchange. These findings revealed that the biomass of S. muticum is a sustainable and promising material for the biosorption of water pollutants.

Due to widespread overuse, pharmaceutical compounds, such as antibiotics, are becoming increasingly prevalent in greater concentrations in aquatic ecosystems. In this study, we investigated the capacity of the white-rot fungus, Coriolopsis gallica (a high-laccase-producing fungus), to biodegrade ampicillin under different cultivation conditions. The biodegradation of the antibiotic was confirmed using high-performance liquid chromatography, and its antibacterial activity was evaluated using the bacterial growth inhibition agar well diffusion method, with Escherichia coli as an ampicillin-sensitive test strain. C. gallica successfully eliminated ampicillin (50 mg L⁻¹) after 6 days of incubation in a liquid medium. The best results were achieved with a 9-day-old fungal culture, which treated a high concentration (500 mg L⁻¹) of ampicillin within 3 days. This higher antibiotic removal rate was concomitant with the maximum laccase production in the culture supernatant. Meanwhile, four consecutive doses of 500 mg L⁻¹ of ampicillin were removed by the same fungal culture within 24 days. After that, the fungus failed to remove the antibiotic. The measurement of the ligninolytic enzyme activity showed that C. gallica laccase might participate in the bioremediation of ampicillin.

In this study, we used sol-gel to synthesize undoped and V-ZnO nanoparticles with different vanadium concentrations (1, 3, and 5 at.%) under supercritical dry conditions of ethanol. XRD spectra showed that the obtained powders are well crystallized in the hexagonal wurtzite structure of ZnO nanoparticles. The average crystallite size, estimated by the Debye-Scherer formula, was found to be equal to 31 nm for the pure sample, and it was decreased to 27 nm for the 3at.% vanadium-doped one. SEM and TEM photographs indicated the spherical and elongated shapes of the nanoparticles. The stretching bands located at 419 cm⁻¹ confirmed ZnO material formation. The efficacy of the produced ZnO NPs against Gram⁺, Gram⁻ bacteria, and fungi was tested. Vanadium-doped ZnO, with low concentrations (10 µg/mL), exhibited a large influence on bacterial and fungi growth inhibition. For example, the inhibition zones IZ of S. aureus and E. coli bacteria reached 16 and 15 mm, respectively, for ZnO:V_1%, while the IZ of these two bacteria were 14 and 12 mm for the undoped ZnO. The use of V-dopant enhanced the production of the reactive oxygen species ROS by the photogeneration of electron-hole pairs due to light absorption by ZnO in the visible region.

The aim of the present research was the efficient degradation of industrial textile wastewater dyes using a very active cloned laccase enzyme. For this purpose, potent laccase-producing bacteria were isolated from soil samples collected from wastewater-replenished textile sites in Punjab, Pakistan. The laccase gene from locally isolated strain LI-81, identified as Bacillus megaterium, was cloned into vector pET21a, which was further transformed into E. coli BL21 codon plus. The optimized conditions for the increased production of laccase include fermentation in a 2% glucose, 5% yeast extract and 250 mg/L CuSO₄ medium with pH 7.5; inoculation with 5% inoculum; induction with 0.1 mM IPTG at 0.5 O.D.; and incubation for 36 h at 37 °C. The crude enzyme produced was employed for the removal of commercially used textile dyes. The dyes were quickly precipitated under optimized reaction conditions. Rose bengal, brilliant green, brilliant blue G, Coomassie brilliant blue R and methylene blue were precipitated at rates of 10.69, 54.47, 84.04, 78.99 and 7.40%, respectively. The FTIR and UV–Vis spectroscopic analyses of dyes before and after confirmed the chemical changes brought about by the cloned laccase that led to the dye removal.

Background/Objectives: Wastewaters containing antibiotics pose risks to human health and soil ecosystems. In this study, the white-rot fungus Coriolopsis gallica (a basidiomycete exhibiting high laccase production) was used for the biotransformation of three antibiotics (50 mg L⁻¹): tetracycline, chloramphenicol, and sulfanilamide. Methods: The biotransformation process was investigated in liquid and solid media using high-performance liquid chromatography (HPLC) and the bacterial growth inhibition agar well diffusion method, respectively. Results: Among the three antibiotics tested, tetracycline showed the highest biotransformation efficiency, achieving a 100% removal rate in the liquid medium and a 100% decrease in the growth inhibition of Escherichia coli in the solid medium. Chloramphenicol and sulfanilamide were partially removed (20% and 16%, respectively) after 12 days of treatment in more than one step without the loss of their antibacterial activities. The presence of these antibiotics in the culture medium of C. gallica enhanced laccase activity, indicating that this ligninolytic enzyme might participate in the biotransformation process. Conclusions: Thus, the results reported in this article extend our knowledge of the catalytic potential of C. gallica and give further perspectives for its application in the biodegradation of antibiotics. To the best of our knowledge, this is the first study wherein C. gallica was used for the treatment of tetracycline, chloramphenicol, and sulfanilamide.

The over use of pharmaceutical compounds, essentially antibiotics, led to an increase of their concentrations in aquatic ecosystems. In this study, the white-rot fungus Coriolopsis gallica (high-laccase-producing fungus) was investigated for the biodegradation of ampicillin (AMP) under different cultivation conditions. The biotransformation of the antibiotic was confirmed by means of high-performance liquid chromatography (HPLC), and the antibacterial activity was evaluated via the bacterial growth inhibition agar well diffusion method using Escherichia coli as an ampicillin-sensitive test strain. The results showed that AMP (50 mg L-1) was totally removed by C. gallica after 6 days of incubation in a liquid medium. The antibiotic removal rate was maximal with a fungal culture aged 9 days. Such a culture achieved the removal of a higher concentration of up to 500 mg L-1 of ampicillin in 3 days. This higher antibiotic removal rate was concomitant with the maximal laccase production in culture supernatant. In addition, four consecutive doses of 500 mg L-1 of ampicillin were transformed by the same fungal culture in 24 days. After that, the fungus was unable to remove the antibiotic. The measurement of ligninolytic enzyme activity showed that laccase of C. gallica might participate in the biotransformation of AMP.