Journal: RSC Advances

Article Title: New insights into enhancement of cadmium biosorption from industrial wastewater through Chlorella sorokiniana HMYA based thin-film

doi: 10.1039/d5ra06679d

Figure Lengend Snippet: (a) Gel electrophoresis of PCR products of 18S gene on 1.5% agarose gel of four samples: M: DNA marker, B (sample 1), C (sample 2), D (sample 3), and W (sample 4). (b) Microscopy image ×40 for Parachlorella kessleri (c) Microscopy image ×40 for Chlorella sorokiniana , (d) Microscopy image ×40 for Scenedesmus vacuolatus , (e) Microscopy image ×40 for Auxenochlorella pyrenoidosa .

Article Snippet: Fourier-transform infrared spectroscopy was employed to investigate the functional groups present in dry alginate and Chlorella sorokiniana HMY-C thin films (before and after cadmium biosorption) with a VERTEX 70v FT-IR spectrometer (Bruker, Germany) at National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.

Techniques: Nucleic Acid Electrophoresis, Agarose Gel Electrophoresis, Marker, Microscopy

Journal: RSC Advances

Article Title: New insights into enhancement of cadmium biosorption from industrial wastewater through Chlorella sorokiniana HMYA based thin-film

doi: 10.1039/d5ra06679d

Figure Lengend Snippet: The workflow form samples collection to promising strain selection. Samples of environmental water and soil were obtained, and enrichment was performed. Microalgal strains were isolated and purified using serial dilution and streaking procedures, with culture purity verified under the microscope. DNA extraction, PCR amplification, sequencing, and the creation of a phylogenetic tree were all used to corroborate taxonomic positioning. Cultivation was optimized in BG-11 medium (pH 7), with continuous illumination (24 : 0 light/dark cycle) at 25 ± 2 °C for 20 days. After comparing growth rates, Chlorella sorokiniana HMYA-C was identified as the most promising strain.

Article Snippet: Fourier-transform infrared spectroscopy was employed to investigate the functional groups present in dry alginate and Chlorella sorokiniana HMY-C thin films (before and after cadmium biosorption) with a VERTEX 70v FT-IR spectrometer (Bruker, Germany) at National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.

Techniques: Selection, Isolation, Purification, Serial Dilution, Microscopy, DNA Extraction, Amplification, Sequencing

Journal: RSC Advances

Article Title: New insights into enhancement of cadmium biosorption from industrial wastewater through Chlorella sorokiniana HMYA based thin-film

doi: 10.1039/d5ra06679d

Figure Lengend Snippet: (a) Differentiation between the biosorption efficiency of different techniques of Chlorella sorokiniana biosorbent for removal of cadmium from aqueous solution with the same condition, (pH 7, temperature 25 °C, 2.3 g/16 ml sodium alginate gel/50 ml of 10 ppm cd concentration), demonstrated that the microalgae in the form of thin film)rectangular sheets(outperform typical spherical alginate beads and wet biomass in cadmium removal efficiency. (b) Impact of pH on (Cd( ii ) biosorption using (2.3 gm) of microalgal dose in (16 ml) of sodium alginate gel/(50 ml) of (10 ppm) concentration of Cd solution at (25 °C), with varying pH from 3 to 9, revealing that pH 7 is the optimal pH for Cd( ii ) removal utilizing Chlorella sorokiniana thin film. (c) The Impact of Temperature on the biosorption of Cd( ii ) utilizing (2.3 gm) biomass in (16 ml) of sodium alginate gel/(50 ml) of (10 ppm) concentration of Cd solution at (pH 7) with varying temperature levels (25, 30, 40, and 60 °C, indicating that the temperature at 25 °C producing the greatest mean removal% of all temperatures examined. (d) The impact of the biosorbent dose on Cd removal efficiency using different microalgal dose (2.3gm, 1.5gm, 0.75gm and 0.30gm) in (16 ml) of sodium alginate gel/50 ml of (10 ppm) concentration of Cd solution at (25 °C) and (pH 7). (e) The impact of the initial metal concentration on the biosorption of Cd( ii ) using different concentration of Cd solution (10, 20, 50, 80) ppm, (2.3 gm) biomass in (16 ml) of sodium alginate gel/50 ml of Cd solution at (25 °C) and (pH 7). (f) The impact of contact time on the biosorption of Cd( ii ) at different contact times (3, 6, 12, 18, 24) h, (2.3 gm) biomass in (16 ml) of sodium alginate gel/50 ml of Cd solution at (25 °C) and (pH 7). (g) Cadmium( ii ) removal efficiency % utilizing algal thin films (hydrogel) and their controls in natural industrial wastewater indicating that 100% removal efficiency of cadmium in two different samples of real industrial wastewater (0.4 ppm Cd) and (2.4 ppm Cd).

Article Snippet: Fourier-transform infrared spectroscopy was employed to investigate the functional groups present in dry alginate and Chlorella sorokiniana HMY-C thin films (before and after cadmium biosorption) with a VERTEX 70v FT-IR spectrometer (Bruker, Germany) at National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.

Techniques: Concentration Assay

Journal: RSC Advances

Article Title: New insights into enhancement of cadmium biosorption from industrial wastewater through Chlorella sorokiniana HMYA based thin-film

doi: 10.1039/d5ra06679d

Figure Lengend Snippet: (a) The FTIR spectrum of calcium alginate thin films before Cd( ii ) biosorption demonstrating the functional groups on the film surface. (b) The FTIR spectrum of calcium alginate thin films following Cd( ii ) biosorption was conducted at 80 ppm Cd 2+ aqueous solution. Indicating the changes in the functional groups on the film surface. (c) The FTIR spectrum of Chlorella sorokiniana thin films prior to Cd( ii ) biosorption highlighting the functional groups detected on the algal surface. (d) The FTIR spectra of Chlorella sorokiniana thin films following Cd( ii ) biosorption was conducted at 80 ppm Cd 2+ aqueous solution shows changes in functional group vibrations due to metal binding.

Article Snippet: Fourier-transform infrared spectroscopy was employed to investigate the functional groups present in dry alginate and Chlorella sorokiniana HMY-C thin films (before and after cadmium biosorption) with a VERTEX 70v FT-IR spectrometer (Bruker, Germany) at National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.

Techniques: Functional Assay, Binding Assay

Journal: RSC Advances

Article Title: New insights into enhancement of cadmium biosorption from industrial wastewater through Chlorella sorokiniana HMYA based thin-film

doi: 10.1039/d5ra06679d

Figure Lengend Snippet: (a) illustrates the EDX spectrum of Chlorella sorokiniana thin film before Cd 2+ biosorption. The spectrum shows the presence of important endogenous elements such as Ca, K, Na, Mg, Cl, P, and S, but no detectable Cd signal, demonstrating the absence of cadmium before exposure. (b) The EDX spectrum of Chlorella sorokiniana thin film following Cd 2+ biosorption, was (conducted at 80 ppm Cd 2+ aqueous solution). The presence of Cd peaks and decreased Ca, Na, and Mg intensities suggest a cation exchange process where Cd 2+ displaces lighter cations on the algal surface. (c) The X-ray diffraction (XRD) characterization of the Chlorella sorokiniana thin films following Cd 2+ biosorption (conducted at 80 ppm Cd 2+ aqueous solution), revealed an amorphous profile with no recognizable crystalline peaks. (d) Chlorella sorokiniana thin film showed a mean zeta potential of −6.6 mV at pH 6, demonstrated high colloidal stability and low electrostatic repulsion.

Article Snippet: Fourier-transform infrared spectroscopy was employed to investigate the functional groups present in dry alginate and Chlorella sorokiniana HMY-C thin films (before and after cadmium biosorption) with a VERTEX 70v FT-IR spectrometer (Bruker, Germany) at National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.

Techniques: Zeta Potential Analyzer

Journal: RSC Advances

Article Title: New insights into enhancement of cadmium biosorption from industrial wastewater through Chlorella sorokiniana HMYA based thin-film

doi: 10.1039/d5ra06679d

Figure Lengend Snippet: (a and b) SEM micrographs of Chlorella sorokiniana thin films before biosorption demonstrated that algal thin films exhibited an extremely varied surface, with high roughness, many protrusions, porous structures and irregular microcracks. These features lead to greater surface area and active sites, which explain why heavy metal adsorption is more effective. The image (a) was acquired at 2.00 KX magnification with a 10 µm scale bar, and a working distance of 9.07 mm. The image (b) was acquired at 3.50 KX magnification with a 5 µm scale bar, and a working distance of 9.35 mm. (c and d) SEM micrographs of Chlorella sorokiniana thin films after biosorption, were conducted at 80 ppm Cd 2+ aqueous solution, revealed a smoother, denser, and more compact algal film surface, indicating the accumulation of metal ions in the algal matrix. The image (c) was acquired at a 5 µm scale bar, 3.50 KX, 22.00 kV EHT, and a 9.12 mm working distance. The image (d) was acquired at a 10 µm scale bar, 2.00 KX, 22.00 kV EHT, and 8.91 mm working distance.

Article Snippet: Fourier-transform infrared spectroscopy was employed to investigate the functional groups present in dry alginate and Chlorella sorokiniana HMY-C thin films (before and after cadmium biosorption) with a VERTEX 70v FT-IR spectrometer (Bruker, Germany) at National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.

Techniques: Adsorption

Journal: RSC Advances

Article Title: New insights into enhancement of cadmium biosorption from industrial wastewater through Chlorella sorokiniana HMYA based thin-film

doi: 10.1039/d5ra06679d

Figure Lengend Snippet: Mechanism of cadmium biosorption by Chlorella sorokiniana thin films is a multi-step process that includes early physical adsorption, intraparticle diffusion, cation exchange and strong chemisorption via functional group interactions, all without the formation of crystalline precipitates. (This illustration proposed based on this current study).

Article Snippet: Fourier-transform infrared spectroscopy was employed to investigate the functional groups present in dry alginate and Chlorella sorokiniana HMY-C thin films (before and after cadmium biosorption) with a VERTEX 70v FT-IR spectrometer (Bruker, Germany) at National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.

Techniques: Adsorption, Diffusion-based Assay, Functional Assay