• Title/Summary/Keyword: Aromatic dyes

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Chemical coagulation and sonolysis for total aromatic amines removal from anaerobically pre-treated textile wastewater: A comparative study

  • Verma, Akshaya K.;Bhunia, Puspendu;Dash, Rajesh R.
    • Advances in environmental research
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    • v.3 no.4
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    • pp.293-306
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    • 2014
  • The present study primarily focuses on the evaluation of the comparative effect of chemical coagulation and ultrasonication for elimination of aromatic amines (AAs) present in anaerobically pretreated textile wastewater containing different types of dyes including azo dyes. Color and COD reduction was also monitored at the optimized conditions. The production of AAs was measured spectrophotometrically in the form of total aromatic amines (TAAs) and also verified with high performance liquid chromatography (HPLC) selectively. A composite coagulant, magnesium chloride (MC) aided with aluminium chlorohydrate (ACH) in an equal ratio (MC + ACH) was utilized during the coagulation process, which yielded 31% of TAAs removal along with 85% of color and 52% of COD reduction. At optimized power (200 W) and sonication time (5 h), an appreciable TAAs degradation efficiency (85%) was observed along with 51% color reduction and 62% COD removal using ultrasonication. The chromatographic data indicate that sulphanilic acid and benzidine types of aromatic amines were produced after the reductive cleavage of utilized textile dyes, which were effectively mineralized after ultrasonication. The degradation followed the first order kinetics with a correlation coefficient ($R^2$) of 0.89 and a first-order kinetic constant (k) of $0.0073min^{-1}$.

Biochemical and Molecular Characterization of Laccases from Wild Mushrooms

  • Ro, Hyeon-Su
    • 한국균학회소식:학술대회논문집
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    • 2014.05a
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    • pp.43-43
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    • 2014
  • White rot fungi have been useful source of enzymes for the degradation of environmental pollutants including polycyclic aromatic hydrocarbons (PAHs) and synthetic dyes. PAHs are widespread organic compounds present in fossil fuels and are routinely generated by incomplete fuel combustion. PAHs are some of the major toxic pollutants of water and soil environments. Synthetic dyes are major water-pollutants, which are toxic to organisms in water environments and interfere photosynthesis of water plants. Removal of PAHs and synthetic dyes has been of interests in the environmental science especially in the environmental microbiology. Mushrooms are fungal groups that function as primary degraders of wood polyphenolic lignin. The ligninolytic enzymes produced by mushroom, including manganese peroxidase, lignin peroxidase, and laccase, mediate the oxidative degradation of lignin. The catalytic power of these enzymes in the degradation of aromatic ring compounds has been sought for the degradation of various organic compounds. In this project, we have screened 60 wild mushroom strains for their degradation activity against two representative PAHs, naphthalene and anthracene, and five aromatic dyes, including alizarin red S, crystal violet, malachite green, methylene blue, rose bengal. The degradation of PAHs was measured by GC while the decolorization of dyes was measured by both UV spectrophotometer and HPLC. As results, 9 wild mushroom strains showed high activity in degradation of PAHs and textile dyes. We also describe the secretive enzyme activities, the transcription levels, and cloning of target genes. In conjunction with this, activities of degradative enzymes, including laccase, lignin peroxidase, and Mn peroxidase, were measured in the liquid medium in the presence of PAHs and dyes. Our results showed that the laccase activity was directed correlated with the degradation, indicating that the main enzyme acts on PAHs and dyes is the laccase. The laccase activity was further simulated by the addition of $Cu^{2+}$ ion. Detailed studies of the enzyme system should be sought for future applications.

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Biodegradation of aromatic dyes and bisphenol A by Trametes hirsuta (Wulfen) Pilat (흰구름버섯에 의한 방향족 염료와 비스페놀 A의 분해)

  • Im, Kyung-Hoan;Baek, Seung-A;Choi, Jae-hyuk;Lee, Tae-Soo
    • Journal of Mushroom
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    • v.17 no.4
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    • pp.247-254
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    • 2019
  • Trametes hirsuta, a white rot fungus, exhibits the ability to degrade synthetic aromatic dyes such as congo red (CR), methylene blue (MB), crystal violet (CV), and remazol brilliant blue R (RBBR). The mycelia of T. hirsuta degraded RBBR and CR more efficiently than CV and MB in the PDB liquid medium (supplemented with 0.01% 4 aromatic dyes). In these mycelia the activities of three ligninolytic enzymes-laccase, manganese peroxidase (MnP), and lignin peroxidase (LiP)-were observed. Among these, laccase was identified to be the major enzyme responsible for the degradation of the four aromatic dyes. The degradation of bisphenol A was also investigated by culturing the mycelia of T. hirsuta in YMG medium supplemented with 100 ppm bisphenol A. The mycelia of T. hirsuta were found to degrade bisphenol A by 71.3, 95.3, and 100 % within incubation periods of 12, 24, and 36 hr, respectively. These mycelia also showed ligninolytic enzyme-like activities including those similar to laccase, MnP, and LiP. Therefore, these results indicate that T. hirsuta could emerge as a potential tool for the remediation of environmental contamination by aromatic dyes and bisphenol A.

Synthesis and Absorption Spectral Properties of Bis-methine Dyes Exemplified by 2,5-Bis-arylidene-1-dicyanomethylene-cyclopentanes

  • Asiri, Abdullah Mohamed
    • Bulletin of the Korean Chemical Society
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    • v.24 no.4
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    • pp.426-430
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    • 2003
  • A range of methine dyes has been synthesized by condensation of highly electronegative active methylene compound dicyanomethylenecyclopentane derived from cyclopentanone with the formyl group of substituted benzaldehydes. The electronic absorption spectroscopic properties of the dyes were investigated. In general, substituents on the aromatic aldehyde moiety have a significant effect on the visible absorption maxima of the dyes; increasing the solvent polarity also showed a pronounced effect on the absorption maxima.

Decoloration of Polycyclic Aromatic Dyes by Mushroom Fungi (버섯균에 의한 염료의 탈색)

  • Sancheti, Sandesh;Sancheti, Shruti;Seo, Sung-Yum
    • The Korean Journal of Mycology
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    • v.37 no.1
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    • pp.73-79
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    • 2009
  • As waste-water disposal plants and oxidative biodegradation for the removal of waste polyaromatic dyes are proved to be ineffective due to the chemical stability of dyes, we studied various strains of mushroom fungi for the removal of these dyes. 100 fungi were isolated from the mushroom samples of 230 species collected in Korea. The growth medium containing a dye (Bromophenol Blue, Congo Red, or Methylene Blue) was inoculated to 10% and incubated for 7 days without shaking. The six strains which removed dyes effectively were selected for further studies with respect to removal of polycyclic aromatic dyes. For all strains, the rate of decoloration of dyes was increasing with Methylene Blue, Bromophenol Blue and Congo Red. The rate of decoloration was higher with stationary culture than with shaking culture. Adsorption of the dyes was the highest with Congo Red.

Degradation of Three Aromatic Dyes by White Rot Fungi and the Production of Ligninolytic Enzymes

  • Jayasinghe, Chandana;Imtiaj, Ahmed;Lee, Geon-Woo;Im, Kyung-Hoan;Hur, Hyun;Lee, Min-Woong;Yang, Hee-Sun;Lee, Tae-Soo
    • Mycobiology
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    • v.36 no.2
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    • pp.114-120
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    • 2008
  • This study was conducted to evaluate the degradation of aromatic dyes and the production of ligninolytic enzymes by 10 white rot fungi. The results of this study revealed that Pycnoporus cinnabarinus, Pleurotus pulmonarius, Ganoderma lucidum, Trametes suaveolens, Stereum ostrea and Fomes fomentarius have the ability to efficiently degrade congo red on solid media. However, malachite green inhibited the mycelial growth of these organisms. Therefore, they did not effectively decolorize malachite green on solid media. However, P. cinnabarinus and P. pulmonarius were able to effectively decolorize malachite green on solid media. T. suaveolens and F. rosea decolorized methylene blue more effectively than any of the other fungi evaluated in this study. In liquid culture, G. lucidum, P. cinnabarinus, Naematoloma fasciculare and Pycnoporus coccineus were found to have a greater ability to decolorize congo red. In addition, P. cinnabarinus, G lucidum and T. suaveolens decolorized methylene blue in liquid media more effectively than any of the other organisms evaluated in this study. Only F. fomentarius was able to decolorize malachite green in liquid media, and its ability to do so was limited. To investigate the production of ligninolytic enzymes in media containing aromatic compounds, fungi were cultured in naphthalene supple mented liquid media. P. coccineus, Coriolus versicolor and P. cinnabarinus were found to produce a large amount of laccase when grown in medium that contained napthalene.

Decolorization of methyl red by selected bacteria in industrial waste sludge

  • Yim, Dae-Woo;Lee, Kang-Min
    • 한국생물공학회:학술대회논문집
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    • 2003.10a
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    • pp.398-401
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    • 2003
  • Azo dyes are aromatic compounds characterized by one or more azo bonds $(R_l-N=N-R_2)$. More than 800,000 tons of dyes are produced annually worldwide, of which 60-70% are azo dyes. During manufacturing, an estimated 10-15% is released into the environment. Aside from their negative aesthetic effects, certain azo dyes have been shown to be toxic and, in some cases, these compounds are carcinogenic and mutagenic. To establish biological wastewater treatment of azo dye, it is essential to discover azo dye-degrading microorganisms. In this report, sludge-contaminated with dyes were gathered through wastewater outlets from the industrial regions. The following to separation of bacteria within them, bacteria which decolorize methyl red, a azo dye, were selected and destined.

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Studies on Silk Fibroin Membranes(II) -Adsorption of Acid Dyes in Silk Fibroin Memberane- (Silk Fibroin 막에 관한 연구 (II) -Silk Fibroin 막에 대한 산성염료의 흡착-)

  • 최해욱;박수민;김경환
    • Textile Coloration and Finishing
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    • v.6 no.3
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    • pp.60-66
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    • 1994
  • With the view of studying on the dual adsorption mechanism of acid dyes in connection with the structural difference of silk fibroin, silk fiber and silk fibroin memberane were used for equilibrium dyeing at $60^{\circ}C$, $70^{\circ}C$, $80^{\circ}C$ and pH 3.2, pH 5.0. The dyes used were C.I.Acid Orange 7 and C.I.Acid Red 88 introduced aromatic hydrocabon into Acid Orange 7. From the adsorption isotherm experiment, the total uptake of dyes can be described by Langmuir sorption and Nernst partition. Nernst partition. Nernst partition coefficient $K_1$ decrease of crystalline regions and orientation. The saturation value S of Acid Red 88 were large than total amino group contents and it was attributed it hydrophobic bond. On the other hand, the standard afficity and enthalpy were increased with the in crease of hydrophobic part of dyes. Both $k_1$ and $K_2$ were decreased with the increase of pH, but $k_2$ were more effected than $K_1$.

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Synthetic aromatic dye degradation by white rot fungus, Pleurotus eryngii (큰느타리(Pleurotus eryngii)의 방향족 합성염료 분해 특성)

  • Im, Kyung-Hoan;Baek, Seung-A;Lee, Tae Soo
    • Journal of Mushroom
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    • v.20 no.2
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    • pp.86-91
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    • 2022
  • Pleurotus eryngii, a white rot fungus, produces two extracellular lignin-degrading enzymes, laccase and manganese peroxidase (MnP). Owing to these enzymes, P. eryngii efficiently degrades synthetic chemicals such as azo, phthalocyanine, and triphenyl methane dyes. In this study, we investigated the degradation processes of four aromatic dyes, congo red (CR), methylene blue (MB), crystal violet (CV), and malachite green (MG), by P. eryngii under solid and liquid culture conditions. CR and MG were the most quickly degraded under solid and liquid culture conditions, respectively. However, compared to CR, CV, and MG, MB was not degraded well under both culture conditions. The activities of ligninolytic enzymes (laccase and MnP) were also investigated. Laccase was identified to be the major enzyme for dye degradation. A positive relationship between decolorization and enzyme activity was observed for CR, MB, and CV degradation. In contrast, decolorization of MG ensued after high enzyme activity. These results indicate that the degradation process differs between MG and the other aromatic dyes. Therefore, P. eryngii could be a potential tool for the bioremediation of synthetic aromatic dye effluent.

Density Functional Theory Study on D-π-A-type Organic Dyes Containing Different Electron-Donors for Dye-Sensitized Solar Cells

  • Song, Jing;Xu, Jie
    • Bulletin of the Korean Chemical Society
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    • v.34 no.11
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    • pp.3211-3217
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    • 2013
  • Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations have been employed to investigate the molecular structures and absorption spectra of three D-${\pi}$-A-type organic dyes (C1-1, D5 and TH208) containing identical ${\pi}$-spacers and electron acceptors, but different aromatic amine electron-donating groups (tetrahydroquinoline, triphenylamine and phenothiazine). The coplanar geometries indicate that the strong conjugation is formed in the dyes. The electronic structures suggest that the intramolecular charge transfer from the donor to the acceptor occurs, and the electron-donating ability of tetrahydroquinoline is stronger than those of triphenylamine and phenothiazine. The computed orbital energy levels of these dyes confirm that the electrons could be injected from the excited dyes to the semiconductor conduction band and the oxidized dyes could be reduced effectively by electrolyte. The TD-DFT results show that the CAM-B3LYP/6-31+G(d, p) is suitable for calculating the absorption spectra. The first absorption band for these dyes is assigned to the HOMO${\rightarrow}$LUMO and HOMO-1${\rightarrow}$LUMO transitions.