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Circular economy solutions for industrial wastes
Published in Klára Szita Tóthné, Károly Jármai, Katalin Voith, Solutions for Sustainable Development, 2019
Klara Szita Tóthné, Zs. István, R.S. Bodnárné, A. Zajáros
Based on professional literature DMSO (dimethyl sulfoxide) is frequently used as a solvent for chemical reactions and is also extensively used as an extractant in biochemistry and cell biology. DMSO can be efficiently recovered from aqueous solutions - even though contaminated with volatile and/or non-volatile impurities - by distillation (Zajáros et al. 2017). The researcher studied the available technological solutions, and in cooperation with project promoter and experts of Budapest Technical University, and based on qualitative and quantitative analysis of the waste water had been chosen the optimal waste water treatment – which is the most adaptable for the existing manufacturing process in point of economic and efficiency. It was the Gaylord-methodology what suited the most from the development objectives.
Effects of Bioremediation on Toxicity, Mutagenesis, and Microbiota in Hydrocarbon-Polluted Soils
Published in Donald L. Wise, Debra J. Trantolo, Remediation of Hazardous Waste Contaminated Soils, 2018
To assay the toxicity of water-insoluble organics using the Microtox system required a versatile and low-toxicity solvent carrier. Dutka and Kwan24 found that dimethyl sulfoxide (DMSO) at a 1 percent concentration was not toxic to the various organisms used in a battery of screening tests, including the Microtox assay, nor were any synergistic effects noted between toxicants and 1 percent DMSO. Microtox assays, combined with the measurement of rates of hydrocarbon disappearance, plant bioassays, and Ames tests, were successfully used to assess the effectiveness of bioremediation of hydrocarbon-contaminated soil in outdoor lysimeters.12,25 In these tests, lysimeter units were filled with a sandy loam soil over a sand drainage layer and were contaminated at the rate of 2.3 ml/cm2 with either jet fuel, heating oil, or diesel oil. As an example, Table 1 shows the results of Microtox assays on the CH2C12 extracts of diesel oil contaminated lysimeter soil. Toxicity increased during the initial phase of biodegradation but started to decrease after 6 and 12 weeks for the treated (liming, fertilization, and tilling) and untreated soil samples, respectively. Toxicity declined to soil background levels by 20 weeks only in bioremediation-treated samples.
Experimental Protocols for Generation and Evaluation of Articular Cartilage
Published in Kyriacos A. Athanasiou, Eric M. Darling, Grayson D. DuRaine, Jerry C. Hu, A. Hari Reddi, Articular Cartilage, 2017
Kyriacos A. Athanasiou, Eric M. Darling, Grayson D. DuRaine, Jerry C. Hu, A. Hari Reddi
Cryopreservation allows for the long-term preservation of cells. Cells stored in liquid nitrogen should be viable for a minimum of 10 years. This allows for preservation of modified or interesting cell lines, pooling of cells from multiple isolation steps for large experiments, and staggering isolation procedures that require cells from primary tissue harvested on multiple days. Cryopreservation of cells requires the use of special freezing medium and control of the freezing rate to minimize cell membrane damage due to ice crystal formation. Dimethyl sulfoxide (DMSO), a solvent, is used in the freezing medium as it prevents ice crystal formation that would rupture cell membranes; however, DMSO itself has deleterious effects on the cells and weakens their membrane, making them more sensitive to injury by shear. Harsh manipulation of cells in DMSO, or extended contact with DMSO at elevated temperatures, will reduce cell viability and should be avoided. Glycerol can also be used as a cryopreservative for certain cell lines sensitive to DMSO; however, as it penetrates cells more slowly, additional care must be taken during freezing.
Toxicological and pharmacokinetic properties of sucralose-6-acetate and its parent sucralose: in vitro screening assays
Published in Journal of Toxicology and Environmental Health, Part B, 2023
Susan S. Schiffman, Elizabeth H. Scholl, Terrence S. Furey, H. Troy Nagle
An exogenous metabolic activation system (MutazymeTM, a Phenobarbital/β-Naphthoflavone (PB/NF) induced liver S9 derived from male Sprague Dawley rats) was obtained from Moltox®, Boone, NC (www.moltox.com). Four genotoxic compounds with either a clastogenic or aneugenic MoA were employed as controls. Methyl methanesulfonate (MMS) and carbendazim (100, 50, 25, or 12.5 µM for both compounds) were utilized as positive controls for the treatment without S9 (−S9) activation. Cyclophosphamide (80, 40, 20 or 10 µM) and benzo(a)pyrene (100, 50, 25, or 12.5 µM) were used as positive controls for the treatment with S9 (+S9) activation. The positive controls were employed to ensure responsiveness of the test system and appropriate clastogenic and/or aneugenic MoA prediction but not to provide a standard for comparison with test articles. Dimethyl sulfoxide (DMSO) was used as the solvent for positive controls.
Mechanochemical remediation of fluoranthene contaminated soil and biotoxicity evaluation
Published in Environmental Technology, 2023
Zhenzhen Yao, Xiaoman He, Mengqiuzi Yin, Han Han, Qiwu Zhang
To evaluate the biotoxicity of remedied soil, vibrio fischeri was utilized as the indicator microorganism due to its high sensitivity and easy culture [25]. The biotoxicity of remedied soil was evaluated using a toxicity tester (GloMax20/20, Pramega Co., USA) to detect the luminescence intensity of vibrio fischeri cultures. A 2 mL of resuscitation solution was added to 1 g of freeze-dried powder containing luminescent bacteria and then cultured in liquid medium to observe luminescence. Dimethyl sulfoxide was used as a solvent to prepare the FL stock solution. Test solutions were diluted in 30 g/L NaCl, with the volume percentage of dimethyl sulfoxide in test solutions kept at a maximum of 0.1%. The PAHs extracted after ball milling under different conditions were diluted in the NaCl solution containing dimethyl sulfoxide to ensure that the luminescence value was between 105 and 108, with 0.8 mL of the organic extract added to 0.1 mL of 3% NaCl solution (containing 0.1% dimethyl sulfoxide), while the control group consisted of 0.9 mL NaCl solution only. Then, 0.1 mL of bacterial suspension was added, and the luminosity was measured after 15 minutes of reaction. The relative rate of luminosity inhibition was calculated according to Equation (1) as follows:
Microwave-assisted safe and efficient synthesis of α-ketothioesters from acetylenic sulfones and DMSO
Published in Journal of Sulfur Chemistry, 2023
Based on our previous work [23,24], and the above control experiments, the reaction mechanism with 1a as an exmple substrate can be proposed as presented in Scheme 4. Initially, dimethyl sulfoxide nucleophilically attacks the acetylenic sulfone 1a, producing a zwitterionic intermediate A, which cyclizes into a four-membered ring intermediate B. It further undergoes a 4e ring opening to generate sulfonium ylide 3 [22]. After the formation of the sulfonium ylide 3, dimethyl sulfide is generated through the decomposition of dimethyl sulfoxide with the aid of the ylide 3 under heating [24]. Dimethyl sulfide dissociates into the methylthiyl and methyl radicals. The methyl radical further reacts with the ylide 3 to form a new radical intermediate C, which abstracts a hydrogen atom from dimethyl sulfide to afford the intermediate 4. It shows a silightly different radical process from our previously reported one [24] because the current reaction is perfomed at lower reaction temperature (120 °C) than previous one (160 °C) and the corresonding dimethyl disulfide and dimethylthiomethane were not observed in the current GC-MS anaylsis.