DEGRADATION OF POLYETHYLENE PLASTIC WASTE BY INDIGENOUS MICROBIAL CONSORTIUM AND FUNGI

Aim: This research aims to determine the ability of indigenous microbial consortium in degrading Low Density Polyethylene (LDPE) plastics. The research start by preparing plastic into 1 x 1 cm2 size which was cut mechanically because the smaller the size of the plastic, the larger the surface area. The plastic is placed in a petri dish containing Nutrient Broth (NB) media. The variations used were bacterial composition (%) 10, 50, and 75, variations in temperature (Â°C) 25, 30, 35, variations in acidity values (pH) 5, 7, 9, and variations in contact time (Td) 10 days. LDPE plastic degradation was analyzed by gravimetric method, Fourier Transform Infrared (FTIR) and Scanning Electron Microscope (SEM). Both types of bacteria were resistant or insensitive to the presence of plastic compounds as xenobiotic substrates because there was no inhibition zone around the plastic samples and they were able to grow on Nutrient Agar (NA) media added with plastic samples. Based on the results of gravimetric and FTIR analysis, the highest removal value was at a temperature variation of 30°C and pH 7 with a bacterial composition of 75% (v/v) which was incubated for 10 days. Methodology and Results:The results of the gravimetric analysis showed that the weight loss in LDPE plastic was 0.1548 gr to 0.1464 gr or 5.47%, while the FTIR analysis showed the intensity removal result was 70.67%. Conclusion, significance, and impact of study: These results were confirmed again using Scanning Electron Microscope (SEM) analysis which showed morphological changes on the surface of LDPE plastic samples. Changes that occur in LDPE plastic samples incubated with indigenous microbial consortium are influenced by several factors, including temperature, pH, contact time, and the presence of bacteria as biodegradators.<div> </div>

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Biosorption of lead ions by exopolysaccharide producing Azotobacter sp.

Journal of Environmental Biology ◽

10.22438/jeb/42/1/mrn-1231 ◽

2021 ◽

Vol 42 (1) ◽

pp. 40-50

Author(s):

P. Dhevagi ◽

◽

S. Priyatharshini ◽

A. Ramya ◽

M. Sudhakaran ◽

...

Keyword(s):

Response Surface Methodology ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Response Surface ◽

Functional Groups ◽

Contact Time ◽

Sewage Water ◽

Energy Dispersive ◽

X Ray ◽

Scanning Electron

Aim: Removal of lead from wastewater using Azotobacter species and optimisation of various parameters to maximise the adsorption of lead by response surface methodology as a tool. Methodology: The bacterial isolate UBI-7 recovered from sewage water irrigated soil was examined for its biosorption potential towards lead. The lead removal efficiency of Azotobacter salinestris was studied with respect to metal concentration (50-250 mg l-1), contact time (24-120 hrs), and pH (4-8).Using response surface methodology, these factors were optimized and R2 value obtained was 0.9710 for lead ions, which indicates the validity of the model. Observation with Fourier Transform Infrared (FTIR), Scanning Electron Microscope imaging (SEM) and Energy Dispersive X-ray Spectroscopic analysis (EDX) were carried out to confirm lead biosorption by Azotobacter salinestris. Results: The lead tolerant bacterium isolated from sewage water irrigated soil (UBI-7) was recognized as Azotobacter salinestris by 16S rRNA based gene sequence analysis. The highest removal percentage of Pb (61.54) was 50 mg l-1 in 72 hrs equilibration period. Interaction effect between different levels of Pb and different contact time of the solution were found to be significant. Lead biosorption by the organism was confirmed by the changes in stretching intensities of functional groups as well as appearance of strong OH stretching at 3291.69 cm-1. Images obtained from Scanning Electron Microscope and Energy Dispersive X-ray Spectroscopic studies of the bacteria (UBI-7) before and after biosorption clearly indicated lead adsorption. Interpretation: Current study proves that the functional groups of Azotobacter salinestris are involved in lead biosorption from aqueous solution which was confirmed through FTIR.EDX analysis also elucidated the lead absorption by the bacterial cells. Hence, this could be effectively utilized for decontamination of lead from the polluted environment. Key words: Azotobacter salinestris, Biosorption, Lead, Response surface methodology

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Effect of vinblastine and cytochalasin B on the cytoskeletal domains in 3T3 cells

Journal of Cell Science ◽

10.1242/jcs.48.1.55 ◽

1981 ◽

Vol 48 (1) ◽

pp. 55-73

Author(s):

J.H. Temmink ◽

H. Spiele

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Cytochalasin B ◽

Morphological Changes ◽

Ultrastructural Changes ◽

3T3 Cells ◽

Cytoplasmic Material ◽

Transmission Electron ◽

Cytoskeletal Elements ◽

Scanning Electron

Normal 3T3 cells were exposed to vinblastine and cytochalasin B in an attempt to correlate the morphological changes of the cell surface as seen in the scanning electron microscope with ultrastructural changes of the cytoskeletal elements as seen in critical-point-dried cells in the transmission electron microscope. Special attention was given to the changes in the cytoplasmic domains distinguished in a previous paper. Cytochalasin B primarily affects the ultrastructure of the cytocortical domain by inducing the formation of condensation foci on the cytoplasmic material. Vinblastine not only induces the depolymerization of microtubules and the perinuclear concentration of intermediate filaments, but it also causes the disappearance of stress fibres from the cortical cytoplasm and the widening of the cytocortex at the expense of the endoplasmic domain. These results support the hypothesis that the differentiation in ultrastructural domains is dependent on the spreading of the cells and their adhesion to substrate.

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Scanning electron microscope evaluation of morphological changes in dental hard tissue after root resection in apicoectomy by erbium, chromium:yttrium-scandium-gallium-garnet laser and #702 TC Bur: Part II

Journal of Dental Lasers ◽

10.4103/2321-1385.197019 ◽

2016 ◽

Vol 10 (2) ◽

pp. 67 ◽

Cited By ~ 1

Author(s):

PrashantDadasaheb Babar ◽

HaridasDas Adhikari

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Morphological Changes ◽

Hard Tissue ◽

Dental Hard Tissue ◽

Scanning Electron

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SINTESIS NANOPARTIKEL COBALT FERRITE (CoFe2O4) DENGAN METODE KOPRESIPITASI DAN APLIKASINYA SEBAGAI FOTOKATALIS

CHEMISTRY PROGRESS ◽

10.35799/cp.12.1.2019.27922 ◽

2020 ◽

Vol 12 (1) ◽

Author(s):

Suaib Suaib ◽

Henry Aritonang ◽

Harry S. J. Koleangan

Keyword(s):

Methylene Blue ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Exposure Time ◽

Contact Time ◽

Cobalt Ferrite ◽

Cofe2o4 Nanoparticles ◽

X Ray ◽

Vis Spectroscopy ◽

Scanning Electron

ABSTRAKTelah dilakukan penelitian tentang kemampuan fotokatalis nanopartikel CoFe2O4 dalam mendegradasi zat warna sintetik Methylene Blue (MB) menggunakan metode kopresipitasi. Nanopartikel tersebut dikarakterisasi menggunakan X-Ray Diffractometry (XRD), Scanning Electron Microscope (SEM) dan spektroskopi UV-vis. Kemampuan fotokatalis dilakukan melalui penentuan konsentrasi Methylene Blue yang tersisa setelah waktu kontak nanopartikel CoFe2O4 dengan larutan Methylene Blue 5 ppm yang disinari sinar UV-A selama 30, 45, 60, 90 dan 120 menit. Penentuan konsentrasi dihitung berdasarkan absorbansi yang didapatkan dari hasil pembacaan uji Spektrofotometri UV-vis lalu digunakan rumus menghitung % degradasi. Hasil penelitian menunjukkan bahwa kemampuan fotokatalis paling baik adalah nanopartikel CoFe2O4 dengan nilai % degradasi untuk variasi waktu penyinaran 60 menit adalah sebesar 40,72 %. ABSTRACTA research on the ability of CoFe2O4 nanoparticles degradation of as photocatalyst to dyemethylene Blue(MB) synthetic using coprecipitation method. The nanoparticles were characterized using X-ray diffractometry (XRD), Scanning Electron Microscope (SEM) and UV-Vis spectroscopy. The ability of the photocatalyst is done by determining the concentration of Methylene Blue residu after contact time of CoFe2O4 nanoparticleswith a solution of Methylene Blue 5 ppm irradiated UV-A for 30, 45, 60, 90 and 120 minutes. Determining the concentration is calculated based on the absorbance obtained from the results of analysis UV-vis spectrophotometry and then used a formula calculating the% degradation. The results showed that ability is the best photocatalyst CoFe2O4 nanoparticles with the value of% degradation for variations in exposure time of 60 minutes is equal to 40.72 %.

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The JSM-890 ultra high resolution Scanning Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152410 ◽

1989 ◽

Vol 47 ◽

pp. 88-89

Author(s):

M. Kersker ◽

C. Nielsen ◽

H. Otsuji ◽

T. Miyokawa ◽

S. Nakagawa

Keyword(s):

Electron Microscope ◽

High Resolution ◽

Scanning Electron Microscope ◽

Morphological Changes ◽

High Current Density ◽

High Signal ◽

Extensive Experience ◽

Transmission Electron ◽

Electron Microscopes ◽

Scanning Electron

Historically, ultra high spatial resolution electron microscopy has belonged to the transmission electron microscope. Today, however, ultra high resolution scanning electron microscopes are beginning to challenge the transmission microscope for the highest resolution.To accomplish high resolution surface imaging, not only is high resolution required. It is also necessary that the integrity of the specimen be preserved, i.e., that morphological changes to the specimen during observation are prevented. The two major artifacts introduced during observation are contamination and beam damage, both created by the small, high current-density probes necessary for high signal generation in the scanning instrument. The JSM-890 Ultra High Resolution Scanning Microscope provides the highest resolution probe attainable in a dedicated scanning electron microscope and its design also accounts for the problematical artifacts described above.Extensive experience with scanning transmission electron microscopes lead to the design considerations of the ultra high resolution JSM- 890.

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