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Cadmium(II) is an important ecotoxic pollutant and may cause health problems if accumulated in the human body. This study focused on the removal of cadmium(II) from aqueous solutions using newly isolated fungus dry mass as the adsorber. The fungus was isolated from soil and identified as Fenellia nivea, based on 18S rRNA sequence analysis. Cadmium(II) biosorption studies were carried out as a function of pH, biomass dose, initial metal concentration, contact time, and temperature. The pH of the aqueous solution strongly influenced the removal percent of Cd(II). The highest cadmium removal yield was obtained at pH 7 (4.9 mg/g) as well as below pH 4, very low yield biosorption of Cd(II) was observed. In the first 5 min, almost 50% Cd(II) ions were removed from the solution and reached equilibrium within 1,440 min at pH 7. Adsorption isotherm follows Langmuir model as well as the dimensionless constant is zero that corresponds to the irreversible adsorption of Cd(II) ions on biomass. The reaction rate constant for the pseudo-second-order adsorption process was found as 3.74 × 10-3 g/mg min. The adsorption process was determined as endothermic and spontaneous with negative standard Gibbs energy change. [ABSTRACT FROM AUTHOR]

In this study, the potential use of the fungus Pleurotus sajor caju to remove phenols (i.e., phenol, o-chlorophenol, p-chlorophenol and 2,4,6-trichlorophenol) from aqueous solutions was evaluated. Biosorption of phenol or chlorophenols reached equilibrium in 4 h. The maximum adsorptions of phenol and chlorophenols onto the Pleurotus sajor caju were 0.95 mmol/g for phenol, 1.24 mmol/g for o-chlorophenol, 1.47 mmol/g for p-chlorophenol and 1.89 mmol/g for 2,4,6-trichlorophenol. The affinity order was as follows: 2,4,6-trichlorophenol > p-chlorophenol > o-chlorophenol > phenol. Phenol and chlorophenols bindings onto Pleurotus sajor caju were clearly pH dependent. The adsorption of phenol and chlorophenols increased with increasing pH. Desorption was achieved using methanol solution (30%, v/v). Pleurotus sajor caju biomass is suitable for reuse for more than five cycles without noticeable loss of adsorption capacity. [Copyright &y& Elsevier]

The potential use of the fungus Phanerochaete chrysosporium to remove chlorophenols (phenol, o-chlorophenol, p-chlorophenol and 2,4,6-trichlorophenol) from aqueous solutions was evaluated. The kinetics of both adsorption and desorption of phenolic compounds was rapid for all adsorbates. The maximum adsorptions of phenol and chlorophenols onto the Phanerochaete chrysosporium were 1.23 mmol/g for phenol, 1.49 mmol/g for o-chlorophenol, 1.78 mmol/g for p-chlorophenol and 2.14 mmol/g for 2,4,6-trichlorophenol. The affinity order was as follows: 2,4,6-trichlorophenol > p-chlorophenol > o-chlorophenol > phenol. Phenol and chlorophenols binding with Phanerochaete chrysosporium were clearly pH dependent. The adsorption of phenol and chlorophenols increased as pH increased. Desorption of phenol or chlorophenols was achieved using methanol solution (30% (v/v)). Phanerochaete chrysosporium is suitable for reuse for more than ten cycles without noticeable loss of adsorption capacity. [Copyright &y& Elsevier]

Among other polysaccharides, levan is a fructan with great potential in biotechnological applications due to its functional properties. The levan has only been available in small quantities because of its high cost. Here, a levan-producing microorganism was isolated from soil and identified as Pseudomonas mandelii. TGA, SEM, FTIR, 1H NMR, 13C NMR and Zetasizer analyses were used to characterize thermal properties and the morphology of the levan. It is the first time, the levan synthesized from P. mandelii is reported as nano sized. The culture conditions were optimized. It is the most comprehensive optimization study regarding levan production of P. mandelii up to the present. The optimum conditions found for levan production were 37 °C, at pH 8, under static conditions, with 15% sucrose and 1.5% mannitol as the C sources and yeast extract as the N source. In addition, the levan production yield was calculated at optimum conditions. Antibacterial activity of levan was evaluated against bacteria and the largest zone of inhibition was observed against E. coli at a concentration of 1000 μg/mL. Antibiofilm activity of levan was evaluated, and we found that all levan concentrations inhibited biofilm formation of all microorganisms in the study. We have shown that the levan from Pseudomonas mandelii induce cytotoxicity breast (MCF-7) cells in a dose-dependent manner. Image 1 • Levan producing bacteria was isolated and identified using 16S rRNA technique. • The levan was characterized using FTIR, C NMR, H NMR SEM, TGA, Zeta-sizer. • Optimum conditions were achieved in polymer production. • The levan yield was calculated.. • Antibacterial, antibiofilm, anti-cancer activities of levan were evaluated.. [ABSTRACT FROM AUTHOR]

The biopolymer of levan was produced with a density of 42.6 g/L by Pseudomonas mandelii in an optimized medium. The produced levan was characterized using FTIR, 1H NMR, and 13C NMR spectroscopy techniques and Zetasizer. More robust films were obtained with glycerol used as plasticizer in levan/sodium bentonite clay films. Film samples were evaluated in terms of water vapor permeability and GLG6 composition (5 g levan + 1 mL glycerol + 2 g Sodium bentonite clay + 50 mL 1% acetic acid) was found to be the most suitable film sample. The film sample was characterized by SEM, AFM, TGA analyses. Different amounts of LL-37 antimicrobial peptide were added to the film samples and antimicrobial properties were examined on different microorganisms. The human cathelicidin LL-37 led to synergistic antimicrobial effects with levan against pathogen microorganisms. The highest antimicrobial effect was observed with an inhibiton zone diameter of 19,5 mm measured on GLG6 film composition with 500 μL of LL-37 antimicrobial peptide on E.coli. Image 1 • Microbial levan was produced using Pseudomonas mandelii. • The films prepared with microbial levan, glycerol, sodium bentonite, PEG. • This is the first work for films of levan, sodium bentonite and LL-37 AMPs. • LL-37 AMPs had synergistic antimicrobial effects with levan against pathogen microorganisms. • The films have the potential to use in wound dressing material. [ABSTRACT FROM AUTHOR]