scholarly journals Trichoderma: Evaluation of Its Degrading Abilities for the Bioremediation of Hydrocarbon Complex Mixtures

2020 ◽  
Vol 10 (9) ◽  
pp. 3152
Author(s):  
Chiara Daccò ◽  
Lidia Nicola ◽  
Marta Elisabetta Eleonora Temporiti ◽  
Barbara Mannucci ◽  
Federica Corana ◽  
...  
Keyword(s):  
Extracellular Enzymes ◽  
Engine Oil ◽  
Gas Chromatography Mass Spectrometry ◽  
Trichoderma Asperellum ◽  
Oil Composition ◽  
Used Engine Oil ◽  
Benzene Toluene ◽  
Xylene Isomers ◽  
Different Strains

Hydrocarbons can have very harmful effects on organisms and the environment, and conventional techniques for their removal are expensive and require the use of chemicals and long-term actions. Trichoderma is an ascomycete genus known to be active on different recalcitrant substrates, since it can produce a set of nonspecific extracellular enzymes generally involved in the degradation of lignin. However, the literature concerning the use of Trichoderma to degrade hydrocarbons is still limited. In this work we aimed to investigate the ability of Trichoderma to exploit used engine oil as its sole carbon source for prospective bioremediation of contaminated substrates. Four different strains belonging to Trichoderma asperellum and Trichoderma harzianum species were tested. The fungi were inoculated in direct contact with used engine oil, and after 45 days the samples were analyzed by gas chromatography/mass spectrometry (GC/MS). The results showed that all strains (except Trichoderma asperellum F1020) significantly changed the oil composition, decreasing the aromatic fraction in favor of the aliphatic one. T. harzianum F26, especially, showed a significant reduction of the BTEX (benzene, toluene, ethylbenzene, and the three xylene isomers) and alkylbenzenes fraction and an increase in short-chain aliphatics C1–C20. Enzymatic tests for laccase and peroxidase were also carried out, demonstrating that every strain seems to express a different mode of action.

scholarly journals Chemical Recycling of WEEE Plastics—Production of High Purity Monocyclic Aromatic Chemicals

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 530
Author(s):  
Tobias Rieger ◽  
Jessen C. Oey ◽  
Volodymyr Palchyk ◽  
Alexander Hofmann ◽  
Matthias Franke ◽  
...  
Keyword(s):  
High Purity ◽  
Fractional Distillation ◽  
Gas Chromatography Mass Spectrometry ◽  
Thermochemical Conversion ◽  
Chemical Recycling ◽  
Pyrolysis Oil ◽  
X Ray ◽  
Benzene Toluene ◽  
Halogen Content ◽  
Methyl Styrene

More than 200 kg real waste electrical and electronic equipment (WEEE) shredder residues from a German dismantling plant were treated at 650 °C in a demonstration scale thermochemical conversion plant. The focus within this work was the generation, purification, and analysis of pyrolysis oil. Subsequent filtration and fractional distillation were combined to yield basic chemicals in high purity. By means of fractional distillation, pure monocyclic aromatic fractions containing benzene, toluene, ethylbenzene, and xylene (BTEX aromatics) as well as styrene and α-methyl styrene were isolated for chemical recycling. Mass balances were determined, and gas chromatography–mass spectrometry (GC-MS) as well as energy dispersive X-ray fluorescence (EDXRF) measurements provided data on the purity and halogen content of each fraction. This work shows that thermochemical conversion and the subsequent refining by fractional distillation is capable of recycling WEEE shredder residues, producing pure BTEX and other monocyclic aromatic fractions. A significant decrease of halogen content (up to 99%) was achieved with the applied methods.

scholarly journals UV Stimulated Manganese Dioxide for the Persulfate Catalytic Degradation of Bisphenol A

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 502
Author(s):  
Guihua Dong ◽  
Bing Chen ◽  
Bo Liu ◽  
Stanislav R. Stoyanov ◽  
Yiqi Cao ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Reaction Mechanisms ◽  
Reduction Rate ◽  
Catalytic Degradation ◽  
Gas Chromatography Mass Spectrometry ◽  
Degradation Pathways ◽  
Industrial Chemicals ◽  
Oh Groups ◽  
Long Term Adverse Effects

One of the most commonly produced industrial chemicals worldwide, bisphenol A (BPA), is used as a precursor in plastics, resins, paints, and many other materials. It has been proved that BPA can cause long-term adverse effects on ecosystems and human health due to its toxicity as an endocrine disruptor. In this study, we developed an integrated MnO2/UV/persulfate (PS) process for use in BPA photocatalytic degradation from water and examined the reaction mechanisms, degradation pathways, and toxicity reduction. Comparative tests using MnO2, PS, UV, UV/MnO2, MnO2/PS, and UV/PS processes were conducted under the same conditions to investigate the mechanism of BPA catalytic degradation by the proposed MnO2/UV/PS process. The best performance was observed in the MnO2/UV/PS process in which BPA was completely removed in 30 min with a reduction rate of over 90% for total organic carbon after 2 h. This process also showed a stable removal efficiency with a large variation of pH levels (3.6 to 10.0). Kinetic analysis suggested that 1O2 and SO4•− played more critical roles than •OH for BPA degradation. Infrared spectra showed that UV irradiation could stimulate the generation of –OH groups on the MnO2 photocatalyst surface, facilitating the PS catalytic degradation of BPA in this process. The degradation pathways were further proposed in five steps, and thirteen intermediates were identified by gas chromatography-mass spectrometry. The acute toxicity was analyzed during the treatment, showing a slight increase (by 3.3%) in the first 30 min and then a decrease by four-fold over 2 h. These findings help elucidate the mechanism and pathways of BPA degradation and provide an effective PS catalytic strategy.

Adipose tissue triglyceride turnover, de novo lipogenesis, and cell proliferation in humans measured with 2H2O

2004 ◽  
Vol 286 (4) ◽  
pp. E577-E588 ◽  
Author(s):  
A. Strawford ◽  
F. Antelo ◽  
M. Christiansen ◽  
M. K. Hellerstein
Keyword(s):  
Cell Proliferation ◽  
Adipose Tissue ◽  
Half Life ◽  
De Novo ◽  
Human Subjects ◽  
De Novo Lipogenesis ◽  
Gas Chromatography Mass Spectrometry ◽  
Distribution Analysis ◽  
Mass Isotopomer Distribution Analysis

The turnover of adipose tissue components (lipids and cells) and the pathways of adipose lipid deposition have been difficult to measure in humans. We apply here a 2H2O long-term labeling technique for concurrent measurement of adipose-triglyceride (TG) turnover, cell (DNA) proliferation, and de novo lipogenesis (DNL). Healthy subjects drank 2H2O (70 ml/day) for 5-9 wk. Subcutaneous adipose tissue aspirates were taken (gluteal, thigh, and flank depots). Deuterium incorporation into TG glycerol (representing all-source TG synthesis), TG palmitate (representing DNL, by mass isotopomer distribution analysis), and DNA (representing cell proliferation) was measured by gas chromatography-mass spectrometry. Subjects tolerated the protocol well, and body 2H2O enrichments were stable. Mean TG-glycerol fractional synthesis was 0.12 (i.e., 12%) with a range of 0.03-0.32 after 5 wk and 0.20 (range 0.08-0.49) after 9 wk (TG half-life 200-270 days). Label decay measurements 5-8 mo after discontinuing 2H2O gave similar turnover estimates. Net lipolysis (TG turnover) was 50-60 g/day. DNL contribution to adipose-TG was 0.04 after 9 wk, representing ∼20% of newly deposited TG. Cell proliferation was 0.10-0.17 after 9 wk (half-life 240-425 days). In summary, long-term 2H2O administration to human subjects allows measurement of the dynamics of adipose tissue components. Turnover of all elements is slow, and DNL contributes ∼20% of new TG.

A Study of Engine Oil Composition Effects on Zeolite-type SCR Catalyst Durability

2007 ◽  
Author(s):  
Masahito Shibata ◽  
Hideyuki Nagata ◽  
Shigeki Takeshima ◽  
Koji Hoshino
Keyword(s):  
Engine Oil ◽  
Oil Composition ◽  
Scr Catalyst ◽  
Composition Effects ◽  
Zeolite Type ◽  
Catalyst Durability

scholarly journals Chemical Composition and Antioxidant and Antimicrobial Activities of Wormwood (Artemisia absinthiumL.) Essential Oils and Phenolics

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Kamel Msaada ◽  
Nidhal Salem ◽  
Olfa Bachrouch ◽  
Slim Bousselmi ◽  
Sonia Tammar ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Essential Oil ◽  
Essential Oils ◽  
Methanolic Extract ◽  
Biological Activities ◽  
Reducing Power ◽  
Antimicrobial Activities ◽  
Gas Chromatography Mass Spectrometry ◽  
Oil Composition ◽  
Antioxidant And Antimicrobial Activities

The aim of this study was to determine the chemical variability of wormwood extracts as affected by the growing region. Antioxidant and antimicrobial activities were also investigated. The essential oil composition variability ofA. absinthiumL. aerial parts collected from four different Tunisian regions was assessed by gas chromatography (GC/FID) and by gas chromatography mass spectrometry (GC/MS). In addition, total polyphenols, flavonoids, and condensed tannins as well as antioxidant, antibacterial, and antifungal activities of methanolic extract and essential oils were undertaken. Chromatographic analysis of wormwood essential oils showed the predominance of monoterpene hydrocarbons represented mainly by chamazulene. RP-HPLC analysis of wormwood methanolic extract revealed the predominance of phenolic acids. Antiradical activity was region-dependant and the methanolic extract of Bou Salem region has the strongest activity (CI50=9.38±0.82 µg/mL). Concerning the reducing power, the methanolic extract of Bou Salem, Jérissa, and Boukornine regions was more active than the positive control. Obtained results of antimicrobial activities showed that wormwood essential oil is endowed with important antibacterial activity which was strongly related to the organoleptic quality of oil which appeared strongly region-dependant.A. absinthiumL. EOs investigated are quite interesting from a pharmaceutical standpoint because of their biological activities.

scholarly journals Chlorine isotope composition in chlorofluorocarbons CFC-11, CFC-12 and CFC-113 in firn, stratospheric and tropospheric air

2015 ◽  
Vol 15 (12) ◽  
pp. 6867-6877 ◽  
Author(s):  
S. J. Allin ◽  
J. C. Laube ◽  
E. Witrant ◽  
J. Kaiser ◽  
E. McKenna ◽  
...  
Keyword(s):  
Isotope Fractionation ◽  
Isotope Composition ◽  
Stratospheric Ozone ◽  
Standard Uncertainty ◽  
Gas Chromatography Mass Spectrometry ◽  
Sources And Sinks ◽  
Chlorine Isotope ◽  
Tropospheric Measurements ◽  
Single Detector

Abstract. The stratospheric degradation of chlorofluorocarbons (CFCs) releases chlorine, which is a major contributor to the destruction of stratospheric ozone (O3). A recent study reported strong chlorine isotope fractionation during the breakdown of the most abundant CFC (CFC-12, CCl2F2, Laube et al., 2010a), similar to effects seen in nitrous oxide (N2O). Using air archives to obtain a long-term record of chlorine isotope ratios in CFCs could help to identify and quantify their sources and sinks. We analyse the three most abundant CFCs and show that CFC-11 (CCl3F) and CFC-113 (CClF2CCl2F) exhibit significant stratospheric chlorine isotope fractionation, in common with CFC-12. The apparent isotope fractionation (ϵapp) for mid- and high-latitude stratospheric samples are respectively −2.4 (0.5) and −2.3 (0.4) ‰ for CFC-11, −12.2 (1.6) and −6.8 (0.8) ‰ for CFC-12 and −3.5 (1.5) and −3.3 (1.2) ‰ for CFC-113, where the number in parentheses is the numerical value of the standard uncertainty expressed in per mil. Assuming a constant isotope composition of emissions, we calculate the expected trends in the tropospheric isotope signature of these gases based on their stratospheric 37Cl enrichment and stratosphere–troposphere exchange. We compare these projections to the long-term δ (37Cl) trends of all three CFCs, measured on background tropospheric samples from the Cape Grim air archive (Tasmania, 1978–2010) and tropospheric firn air samples from Greenland (North Greenland Eemian Ice Drilling (NEEM) site) and Antarctica (Fletcher Promontory site). From 1970 to the present day, projected trends agree with tropospheric measurements, suggesting that within analytical uncertainties, a constant average emission isotope delta (δ) is a compatible scenario. The measurement uncertainty is too high to determine whether the average emission isotope δ has been affected by changes in CFC manufacturing processes or not. Our study increases the suite of trace gases amenable to direct isotope ratio measurements in small air volumes (approximately 200 mL), using a single-detector gas chromatography–mass spectrometry (GC–MS) system.

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