Journal articles: 'Solventi organici'

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Schulz, Lara, and Siegfried Waldvogel. "Solvent Control in Electro-Organic Synthesis." Synlett 30, no. 03 (December 13, 2018): 275–86. http://dx.doi.org/10.1055/s-0037-1610303.

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Exploiting the solvent control within electro-organic conversions is a far underestimated parameter in prep-scale electrolysis. The beneficial application in several transformations is outlined and in particular discussed for the dehydrogenative coupling of arenes and heteroarenes. This simple electrolytic strategy in fluorinated solvents allows the modulation of the substrate’s nucleophilicity and the stabilization of the intermediates as well as of the final product from over-oxidation.1 Introduction2 Solvent Effects in Kolbe Electrolysis and Anodic Fluorination3 Unique Solvent Effects of 1,1,1,3,3,3-Hexafluoropropan-2-ol (HFIP)4 Anodic Dehydrogenative Coupling Reactions with Use of HFIP as the Solvent5 Conclusion

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Maheshwari, R. K., Shruti Jain, Anjali Padria, Pawan Mulani, Jaydeep Singh Baghel, and Neelesh Maheshwari. "''Eco-friendly extraction using solids'' - A novel application of mixed solvency concept." Journal of Drug Delivery and Therapeutics 9, no. 2 (March 15, 2019): 244–49. http://dx.doi.org/10.22270/jddt.v9i2.2409.

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As per the mixed solvency concept (proposed by Dr. R.K. Maheshwari), each and every substance present on the earth has got solubilizing property i.e. all the liquids, gases and solids possess solubilizing power. In the mixed solvency concept, each substance is a solubilizer. We know that all the liquids (matter in liquid state at room temperature) are known as solvents. No solvent is universal solvent. We can say that all the solvents are good solvents for some solutes and bad solvents for other solutes. Similarly, all gases and solids have good solubilizing power for some solutes and bad solubilizing power for other solutes. Organic solvents have innumerous adverse effects. Such organic solvents should be replaced by other eco-friendly alternative sources. The main objective of this research work is to provide a novel idea to the researchers that solids can also be employed for extraction of active constituents from powders of roots, leaves, seeds, fruits, bark of plants etc. In the present investigation, sesame oil has been extracted from powdered seeds of sesame using solubilizing powers of two solids, thymol and menthol using different methods. Melted thymol (temperature about 50°C), melted menthol (temperature about 45°C) were observed to have very good solubility for sesame oil. Therefore, they were used for extraction of sesame oil. Ethanol was found to be bad solvent for sesame oil. Thymol and menthol improved the solubility of sesame oil in ethanol and helped in extraction. Thymol and menthol are easily removed at about 80°C. Organic solvents are removed from extracts by suitable methods like heating, vacuum distillation etc. These solids (menthol and thymol) are also removable. Also, they can be recollected using suitable methods for recycling purposes. Keywords: Extraction, mixed solvency concept, sesame oil, menthol, thymol, eutectic liquid, solubilizer

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Winterton, Neil. "The green solvent: a critical perspective." Clean Technologies and Environmental Policy 23, no. 9 (September 30, 2021): 2499–522. http://dx.doi.org/10.1007/s10098-021-02188-8.

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AbstractSolvents are important in most industrial and domestic applications. The impact of solvent losses and emissions drives efforts to minimise them or to avoid them completely. Since the 1990s, this has become a major focus of green chemistry, giving rise to the idea of the ‘green’ solvent. This concept has generated a substantial chemical literature and has led to the development of so-called neoteric solvents. A critical overview of published material establishes that few new materials have yet found widespread use as solvents. The search for less-impacting solvents is inefficient if carried out without due regard, even at the research stage, to the particular circumstances under which solvents are to be used on the industrial scale. Wider sustainability questions, particularly the use of non-fossil sources of organic carbon in solvent manufacture, are more important than intrinsic ‘greenness’. While solvency is universal, a universal solvent, an alkahest, is an unattainable ideal.

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Jain, Shuchi, and Amreen Khan. "Titrimetric Analysis of Aceclofenac Sodium by Using Mixed Solvency." International Journal of Pharmaceutical Sciences and Medicine 7, no. 8 (August 30, 2022): 25–32. http://dx.doi.org/10.47760/ijpsm.2022.v07i08.004.

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Titration is a method of quantitative/chemical analysis which can be used to determine the concentration of a known reactant. Mixed solvency has been widely used to enhance the aqueous solubility of a large number of poorly water-soluble drugs. Various organic solvents like methanol, chloroform, dimethyl formamide and ethanol have been employed for solubilization of poorly water-soluble drugs. Organic solvents because of their higher cost, toxicities and pollution are not used as solvent. In the present investigation a sodium benzoate, sodium citrate, sodium salicylate solution (an economic agent) was employed as a hydrotropic solubilizing agent to solubilize the poorly water-soluble drug aceclofenac for its titrimetric analysis in bulk sample and tablets precluding the use of organic solvent. The proposed method is new, simple, precise and inexpensive. The results of the analysis have been validated statistically. The mean % recoveries were found to be close to 100, indicating the accuracy of the proposed method.

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Ha, Le Thanh, and Le Duy Thang. "OPTIMIZATION OF CONDITIONS FOR CAROTENOIDS EXTRACTION FROM SHRIMP WASTE USING ORGANIC SOLVENT." Vietnam Journal of Science and Technology 57, no. 3B (November 12, 2019): 42. http://dx.doi.org/10.15625/2525-2518/57/3b/14111.

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In this study, factors affecting the extraction yield of carotenoids from dry shrimp waste by organic solvents such as ratio of hexane / acetone, ratio of solvent / shrimp waste, extraction temperature, extraction time, extraction method such as dynamic or static have been studied. The results showed that the solvent ratio hexane: acetone = 3: 1 gave the highest carotenoid yield. In this ratio of solvent’s mixture, the yield reached highest at temperature 60 °C for 2 hours, which was 44,64 µg / g raw shrimp waste (d.b.) (ratio of solvent to raw material 3/1). Ultrasound or vortexing gave higher extraction yield than in static conditions, which was 1.5- to 1.8- fold increase, respectively. At the ratio of solvent: dried shrimp = 4: 1, the amount of carotenoid recovered at 60°C for 2 hours reached 57.4 µg / g. However, if the shrimp waste was hydrolyzed with Alcalase at 50°C for 4 hours before extraction by solvent, the amount of carotenoid recovered achieved 149 µg / g of raw material

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Istyami, Astri Nur, Tatang Hernas Soerawidjaja, Tirto Prakoso, and Tri Ari Penia Kresnowati. "Performance of Various Organic Solvents as Reaction Media in Plant Oil Lipolysis with Plant Lipase." Reaktor 18, no. 2 (August 24, 2018): 71. http://dx.doi.org/10.14710/reaktor.18.2.71-75.

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Fatty acids are intermediate substances in synthesis of oleochemical products. Enzymatic technology of fatty acids production (also known as lipolysis) is now developing as potential substitution for the conventional production of fatty acid, i.e. thermal hydrolysis of triglyceride. It offers more economical process condition, low energy consumption, and minimal product degradation compared to the conventional process. This research aims to evaluate performance of various organic solvents as reaction media in lipolysis with plant latex lipase. Organic solvents observed were chloroform, n-hexane, diethyl ether, benzene, acetone, ethanol, methanol, n-heptane, and isooctane. Analysis of each organic solvent effect on lipolysis was described based on solvents properties. Conversion of lipolysis with organic solvents is 0,10-1,25 times fold compared to conversion of non-solvent lipolysis. We suggest that dielectric constant and viscosity are the two main organic solvent properties affecting lipase performance in lipolysis. Overall, n-hexane, n-heptane, and isooctane are recommended to be used as reaction media in lipolysis with plant lipase because their effects to degree of lipolysis are positive. Keywords: lipolysis; lipase; organic solvent; frangipani

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Ārija Baķe, Mārīte, Maija Eglīte, Žanna Martinsone, Inita Buiķe, Anita Piķe, and Pāvels Sudmalis. "Organic solvents as chemical risk factors of the work environment in different branches of industry and possible impact of solvents on workers' health." Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. 64, no. 1-2 (January 1, 2010): 25–32. http://dx.doi.org/10.2478/v10046-010-0011-z.

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Organic solvents as chemical risk factors of the work environment in different branches of industry and possible impact of solvents on workers' health The aim of our study was to investigate organic solvents as chemical risk factors of the work environment in different branches of the industry in Latvia during 1998-2006 and to evaluate the possible impact of solvents to worker health according to the exposure index. The work conditions were studied in 116 enterprises of different branches of industries in Latvia. The analysis of 1790 measurements showed that organic solvents in the work environment have different degrees of exposure probability risk on worker health. The exposure levels in workplaces differ. More than half of surveyed workplaces (56.7%) had a low organic solvent exposure probability level, in 25.2% workplaces it was medium, and in 18.1% workplaces high. The most widely used organic solvents were aromatic hydrocarbons, which was recorded in 35% of the measurements made during assessment of aromatic hydrocarbon group organic solvent exposure in the work environment. In most workplaces several solvents were present simultaneously. Since solvents have a one-way effect on the human body, the actual exposure risk level is higher than shown when evaluating the exposure index of a single solvent only.

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Huang, Chia-Yi, and Shih-Hung Lin. "Organic Solvent Sensors Using Polymer-Dispersed Liquid Crystal Films with a Pillar Pattern." Polymers 13, no. 17 (August 29, 2021): 2906. http://dx.doi.org/10.3390/polym13172906.

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An organic solvent sensor of polymer-dispersed liquid crystals (PDLCs) film is fabricated by a combination of tri-functional monomers and LCs. When the patterned PDLC film comes into contact with the organic solvent, the organic solvent will penetrate into the film to induce the orientation of the liquid crystals, which will change from an ordered to a disordered state, which causes the PDLC film to scatter incident light. The experiment used acetone and ethanol as the organic solvents of interest. The results show that the patterned PDLC film has a stronger response to acetone than to ethanol. Based on the difference in the intensity of light scattering and the response time of the patterned PDLC film to different organic solvents, the results can be used to identify and recognize different types of organic solvents.

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Chemat, Abert Vian, Ravi, Khadhraoui, Hilali, Perino, and Tixier. "Review of Alternative Solvents for Green Extraction of Food and Natural Products: Panorama, Principles, Applications and Prospects." Molecules 24, no. 16 (August 19, 2019): 3007. http://dx.doi.org/10.3390/molecules24163007.

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In recent years, almost all extraction processes in the perfume, cosmetic, pharmaceutical, food ingredients, nutraceuticals, biofuel and fine chemical industries rely massively on solvents, the majority of which have petroleum origins. The intricate processing steps involved in the industrial extraction cycle makes it increasingly difficult to predict the overall environmental impact; despite the tremendous energy consumption and the substantial usage of solvents, often the yields are indicated in decimals. The ideal alternative solvents suitable for green extraction should have high solvency, high flash points with low toxicity and low environmental impacts, be easily biodegradable, obtained from renewable (non-petrochemical) resources at a reasonable price and should be easy to recycle without any deleterious effect to the environment. Finding the perfect solvent that meets all the aforementioned requirements is a challenging task, thus the decision for the optimum solvent will always be a compromise depending on the process, the plant and the target molecules. The objective of this comprehensive review is to furnish a vivid picture of current knowledge on alternative, green solvents used in laboratories and industries alike for the extraction of natural products focusing on original methods, innovation, protocols, and development of safe products.

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Niu, Ru Xuan, Ying Qun Ma, Qun Hui Wang, Bo Yue, Yu Fei Yang, and Hong Zhi Ma. "Environmental Risk Assessment and Environmental Management of Waste Organic Solvents in Electronics Industry." Applied Mechanics and Materials 768 (June 2015): 595–601. http://dx.doi.org/10.4028/www.scientific.net/amm.768.595.

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Waste organic solvents have been classified as hazardous waste in many countries because of their toxicity, high volatility and Ignitability. Waste organic solvents are produced in a lot of industries including of the electronics industry. In this industry, organic solvents are used as cleaning agent and developer, which would generate a lot of waste organic solvents. In China, in the management and re-use of waste organic solvents, the current management systems are not completely. So it is need to learn the laws and regulations, treatment and disposal technologies, control standards of waste organic solvents generated in electronics industry in the developed countries. In this paper, based on an organic solvent waste for feature analysis and risk assessment, which generated by the electronics industry, Therefore, the waste organic solvent has a more serious environmental risk and human health risk through the soil and underwater than the air. Forbid the waste organic solvents produced company casual dump, in order to avoid the waste pollution. The evaluation result of the waste organic solvents produced by China's electronics industry is the data basis to obtain relevant management regulations On this basis, put forward the suggestion and management specifications of waste organic solvents, provide strong supports for the revise of the " National Catalogue of Hazardous Wastes ".

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Di Carmine, Graziano, Andrew P. Abbott, and Carmine D'Agostino. "Deep eutectic solvents: alternative reaction media for organic oxidation reactions." Reaction Chemistry & Engineering 6, no. 4 (2021): 582–98. http://dx.doi.org/10.1039/d0re00458h.

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ARAGÓN, D. M., J. E. ROSAS, and F. MARTÍNEZ. "EFFECT OF THE IBUPROFEN SOLUBILITY IN ACETONE AND DICHLOROMETHANE ON THE DRUG RELEASE PROFILES FROM PLGA MICROSPHERES." Latin American Applied Research - An international journal 44, no. 1 (January 31, 2014): 87–92. http://dx.doi.org/10.52292/j.laar.2014.423.

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Acetone and dichloromethane were used as organic solvent to prepare ibuprofen-loaded PLGA microspheres by the emulsion-solvent evaporation method. Some microspheres properties, such as microencapsulation efficiency and particle size, were affected by the organic solvent used. Depending on the organic solvent used microparticles obtained exhibited different controlled release profiles. In all cases it was extended up to 15 days. The obtained formulations did not exhibit zero- or first-order release kinetics and non-agreement with the Higuchi or Korsmeyer-Peppas models was found. On the other hand, the model proposed by Gallagher and Corrigan for PLGA systems described fully the drug dissolution processes from the microspheres obtained. A relationship between the ibuprofen solubility in both organic solvents studied and some parameters estimated for the dissolution model of the microparticles prepared with these solvents was also found. Thus, it could be propose that the drug solubility in different organic solvents affects the physical characteristics of microparticles and their dissolution profiles.

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Matsui, Ken, Shinya Teranishi, Shohei Kamon, Kouichi Kuroda, and Mitsuyoshi Ueda. "Discovery of a Modified Transcription Factor Endowing Yeasts with Organic-Solvent Tolerance and Reconstruction of an Organic-Solvent-Tolerant Saccharomyces cerevisiae Strain." Applied and Environmental Microbiology 74, no. 13 (May 9, 2008): 4222–25. http://dx.doi.org/10.1128/aem.02874-07.

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ABSTRACT Organic-solvent tolerance in Saccharomyces cerevisiae strain KK-211, which was first isolated as an organic-solvent-tolerant strain, depends on point mutation (R821S) of the transcription factor Pdr1p. The integration of the PDR1 R821S mutation into wild-type yeast results in organic-solvent tolerance, and the PDR1 R821S mutant can reduce carbonyl compounds in organic solvents.

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Zhang, Xiaowei, Liqun Yang, Chong Zhang, Danhua Liu, Shu Meng, Wei Zhang, and Shengnan Meng. "Effect of Polymer Permeability and Solvent Removal Rate on In Situ Forming Implants: Drug Burst Release and Microstructure." Pharmaceutics 11, no. 10 (October 10, 2019): 520. http://dx.doi.org/10.3390/pharmaceutics11100520.

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To explore the mechanism of drug release and depot formation of in situ forming implants (ISFIs), osthole-loaded ISFIs were prepared by dissolving polylactide, poly(lactide-co-glycolide), polycaprolactone, or poly(trimethylene carbonate) in different organic solvents, including N-methyl-2-pyrrolidone (NMP), dimethyl sulfoxide (DMSO), and triacetin (TA). Drug release, polymer degradation, solvent removal rate and depot microstructure were examined. The burst release effect could be reduced by using solvents exhibit slow forming phase inversion and less permeable polymers. Both the drug burst release and polymer depot microstructure were closely related to the removal rate of organic solvent. Polymers with higher permeability often displayed faster drug and solvent diffusion rates. Due to high polymer-solvent affinity, some of the organic solvent remained in the depot even after the implant was completely formed. The residual of organic solvent could be predicted by solubility parameters. The ISFI showed a lower initial release in vivo than that in vitro. In summary, the effects of different polymers and solvents on drug release and depot formation in ISFI systems were extensively investigated and discussed in this article. The two main factors, polymer permeability and solvent removal rate, were involved in different stages of drug release and depot formation in ISFI systems.

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Aljuboori, Sahar Balkat, Nedaa Abdulhameed Abdulrahim, Shuhad Yassen, and Heba Hashim Khaleel. "Organic Synthesis under Solvent-free Condition (Green Chemistry): A Mini Literature Review." Al-Rafidain Journal of Medical Sciences ( ISSN: 2789-3219 ) 3 (December 17, 2022): 109–15. http://dx.doi.org/10.54133/ajms.v3i.94.

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Solvents are important components in the pharmaceutical and chemical industries, and they are increasingly being used in catalytic reactions. Solvents have a significant influence on the kinetics and thermodynamics of reactions, and they can significantly change product selectivity. Solvents can influence product selectivity, conversion rates, and reaction rates. However, solvents have received a lot of attention in the field of green chemistry. This is due to the large amount of solvent that is frequently used in a process or formulation, particularly during the purification steps. However, neither the solvent nor the active ingredient in a formulation is directly responsible for the reaction product's composition. Because these characteristics have little bearing on how well or quickly the system in which the solvent is applied works, it appears unnecessary to use toxic, combustible, or environmentally hazardous solvents. However, the beneficial properties of the solvent required for the application are strongly linked to these unfortunate side effects of solvent use. Distillation can be used to recover and purify solvents because they are volatile; however, this process can produce unwanted air pollutants and be hazardous to workers during exposure. .

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Safaei, Zahra, Szymon Bocian, and Bogusław Buszewski. "Green chromatography-carbon footprint of columns packed with core–shell materials." RSC Adv. 4, no. 96 (2014): 53915–20. http://dx.doi.org/10.1039/c4ra11456f.

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Acetonitrile and methanol are the most popular organic solvents employed in RP HPLC, so it is important to minimize the environmental impact of organic solvent and the use of environmentally friendly solvents.

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Roy, J. L., and W. B. McGill. "Flexible conformation in organic matter coatings: An hypothesis about soil water repellency." Canadian Journal of Soil Science 80, no. 1 (February 1, 2000): 143–52. http://dx.doi.org/10.4141/s98-093.

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Some soils develop severe water repellency several years or decades following oil contamination. We previously reported that soil water repellency is completely eliminated by extraction with amphiphilic solvents, but barely reduced by extraction with nonpolar solvents. We report here on solvent-induced reversible soil water repellency. Our results indicate that: (i) water repellency is completely eliminated following extraction with amphiphilic solvent, but partially restored following subsequent exposure to nonpolar, non-H-bonding solvent; (ii) extraction with nonpolar, non-H-bonding solvent generates water repellency in readily wettable control wettable soils, but not in pristine wettable soils, and (iii) repeated sequential extractions alternating between amphiphilic and nonpolar, non-H-bonding solvent increase extractable material and reduce the magnitude of solvent-induced soil water repellency with time.We attribute reversible soil water repellency to solvent-induced changes in the conformation of causative agents of soil water repellency. Recent literature reports on the structural flexibility of "insoluble" organic macromolecules are discussed for supporting evidence. We propose that exposure to nonpolar, non-H-bonding solvents induces stretching of surface-exposed, nonpolar moieties (i.e. alkyl chains), whereas exposure to polar, H-bonding solvents induces their coiling. These solvent-induced conformational changes are retained upon solvent removal. Our results indicate that the wettability of oil-contaminated soils depends on both the interfacial conformation and the fractional coverage of their surface-exposed nonpolar moieties. Key words: Soil water repellency, crude oil, hydrophobic soil, conformational flexibility, swelling, solvents

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Maiangwa, Jonathan, Mohd Shukuri Mohamad Ali, Abu Bakar Salleh, Raja Noor Zaliha Raja Abd Rahman, Yahaya M. Normi, Fairolniza Mohd Shariff, and Thean Chor Leow. "Lid opening and conformational stability of T1 Lipase is mediated by increasing chain length polar solvents." PeerJ 5 (May 18, 2017): e3341. http://dx.doi.org/10.7717/peerj.3341.

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The dynamics and conformational landscape of proteins in organic solvents are events of potential interest in nonaqueous process catalysis. Conformational changes, folding transitions, and stability often correspond to structural rearrangements that alter contacts between solvent molecules and amino acid residues. However, in nonaqueous enzymology, organic solvents limit stability and further application of proteins. In the present study, molecular dynamics (MD) of a thermostable Geobacillus zalihae T1 lipase was performed in different chain length polar organic solvents (methanol, ethanol, propanol, butanol, and pentanol) and water mixture systems to a concentration of 50%. On the basis of the MD results, the structural deviations of the backbone atoms elucidated the dynamic effects of water/organic solvent mixtures on the equilibrium state of the protein simulations in decreasing solvent polarity. The results show that the solvent mixture gives rise to deviations in enzyme structure from the native one simulated in water. The drop in the flexibility in H2O, MtOH, EtOH and PrOH simulation mixtures shows that greater motions of residues were influenced in BtOH and PtOH simulation mixtures. Comparing the root mean square fluctuations value with the accessible solvent area (SASA) for every residue showed an almost correspondingly high SASA value of residues to high flexibility and low SASA value to low flexibility. The study further revealed that the organic solvents influenced the formation of more hydrogen bonds in MtOH, EtOH and PrOH and thus, it is assumed that increased intraprotein hydrogen bonding is ultimately correlated to the stability of the protein. However, the solvent accessibility analysis showed that in all solvent systems, hydrophobic residues were exposed and polar residues tended to be buried away from the solvent. Distance variation of the tetrahedral intermediate packing of the active pocket was not conserved in organic solvent systems, which could lead to weaknesses in the catalytic H-bond network and most likely a drop in catalytic activity. The conformational variation of the lid domain caused by the solvent molecules influenced its gradual opening. Formation of additional hydrogen bonds and hydrophobic interactions indicates that the contribution of the cooperative network of interactions could retain the stability of the protein in some solvent systems. Time-correlated atomic motions were used to characterize the correlations between the motions of the atoms from atomic coordinates. The resulting cross-correlation map revealed that the organic solvent mixtures performed functional, concerted, correlated motions in regions of residues of the lid domain to other residues. These observations suggest that varying lengths of polar organic solvents play a significant role in introducing dynamic conformational diversity in proteins in a decreasing order of polarity.

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Iwase, M., N. Kurata, R. Ehana, Y. Nishimura, T. Masamoto, and H. Yasuhara. "Evaluation of the effects of hydrophilic organic solvents on CYP3A-mediated drug-drug interaction in vitro." Human & Experimental Toxicology 25, no. 12 (December 2006): 715–21. http://dx.doi.org/10.1177/0960327106071979.

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This study evaluated the effects of the commonly used hydrophilic organic solvents, acetonitrile, methanol, ethanol, 1-propanol, dimethyl sulfoxide (DMSO), N,N-dimethylformamide, polyethylene glycol and propylene glycol, on CYP3A in pooled human liver microsomes, using testosterone and midazolam as substrates. Furthermore, we examined the modulation effect of organic solvents on CYP3A inhibition by ketoconazole. Testosterone 6b-hydroxylation activity was potently inhibited in the presence of DMSO and 1-propanol in a concentration-dependent manner. Midazolam 1'-hydroxylation activity, however, was weakly inhibited only by 1% of DMSO, the highest concentration used in this study. Moreover, the potency of ketoconazole to inhibit CYP3A activities was variable, depending on the organic solvent used as a dissolving solvent for ketoconazole. Our data indicate that each organic solvent had an effect on CYP3A4 activity, evaluated by both substrates with different magnitudes. Furthermore, it was shown that the effects of organic solvents on CYP3A activity are substrate-dependent. The present study also shows that methanol had little effect on either substrate.

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Li, Xian-Zhi, Li Zhang, and Keith Poole. "Role of the Multidrug Efflux Systems ofPseudomonas aeruginosa in Organic Solvent Tolerance." Journal of Bacteriology 180, no. 11 (June 1, 1998): 2987–91. http://dx.doi.org/10.1128/jb.180.11.2987-2991.1998.

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ABSTRACT Multidrug efflux pumps with a broad substrate specificity make a major contribution to intrinsic and acquired multiple antibiotic resistance in Pseudomonas aeruginosa. Using genetically defined efflux pump mutants, we investigated the involvement of the three known efflux systems, MexA-MexB-OprM, MexC-MexD-OprJ, and MexE-MexF-OprN, in organic solvent tolerance in this organism. Our results showed that all three systems are capable of providing some level of tolerance to organic solvents such as n-hexane andp-xylene. Expression of MexAB-OprM was correlated with the highest levels of tolerance, and indeed, this efflux system was a major contributor to the intrinsic solvent tolerance of P. aeruginosa. Intrinsic organic solvent tolerance was compromised by a protonophore, indicating that it is substantially energy dependent. These data suggest that the efflux of organic solvents is a factor in the tolerance of P. aeruginosa to these compounds and that the multidrug efflux systems of this organism can accommodate organic solvents, as well as antibiotics.

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Görbitz, Carl Henrik, and Hans-Petter Hersleth. "On the inclusion of solvent molecules in the crystal structures of organic compounds." Acta Crystallographica Section B Structural Science 56, no. 3 (June 1, 2000): 526–34. http://dx.doi.org/10.1107/s0108768100000501.

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The Cambridge Structural Database has been searched for all crystal structures including organic solvent molecules (solvates) and solvent water molecules (hydrates). Well above 300 different solvent molecules were identified and the frequencies with which they occur in crystal structures, as a function of the year of publication, were established. The crystal structures are classified as `organic' and `metalloorganic'; it is shown that the relative prevalences of various cocrystallized solvents are different in the two groups. Several frequently used organic solvents are also common ligands for metal ions. Special interest has been focused on the existence of heterosolvates, i.e. crystal structures which include more than one type of solvent molecule. Up to five different types of solvent molecules were found in a single crystal structure. It is suggested that the use of solvent mixtures during crystallizations may prove to be a more useful and versatile approach for obtaining crystals of high-molecular-weight organic compounds than has hitherto been recognized.

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Zanuncio, Andressa, Luiza Lelis, Odilon Junior, Regis Martins, Alexandre Diniz, Marcell Pereira, Lucas Amaral, and João Paulo Nunes. "RELATO DE TRÊS CASOS: INTOXICAÇÃO POR SOLVENTES ORGÂNICOS." Revista Criminalistica e Medicina Legal 7, no. 1 (2022): 36–40. http://dx.doi.org/10.51147/rcml067.2022.

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Inalantes são solventes com características de serem substâncias facilmente voláteis e que podem ser inaladas, ou seja, podem ser introduzidas no organismo por meio da aspiração pelo nariz ou boca. São substâncias líquidas, altamente voláteis, com baixo ponto de ebulição. Representados, principalmente, pelo “lança perfume” e sua versão caseira chamada “cheirinho de loló”, são à base de cloreto de etila e clorofórmio, considerados depressores do sistema nervoso central (SNC). O comércio clandestino vem adicionando substâncias à sua composição como o solvente tricloroetileno, um hidrocarboneto clorado, para potencializar os efeitos psicotrópicos dessas drogas. Esses solventes, usados repetidas vezes em um reduzido espaço de tempo, causam edema, depressão respiratória, hipóxia, arritmias cardíacas e reflexos vagais, podendo levar à morte súbita clássica: “sudden sniffin death”. O objetivo deste artigo foi relatar três casos de intoxicação por inalantes, necropsiados no Posto Médico Legal de uma cidade de médio porte de Minas Gerais, Brasil. Os três casos relatados têm como causa da morte a intoxicação por inalação de solventes orgânicos. Os relatos são fundamentais para a conscientização sobre os riscos dos abusos dessas drogas.

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Lee, Yongchul, Dongil Ho, Federica Valentini, Taeshik Earmme, Assunta Marrocchi, Luigi Vaccaro, and Choongik Kim. "Improving the charge transport performance of solution-processed organic field-effect transistors using green solvent additives." Journal of Materials Chemistry C 9, no. 46 (2021): 16506–15. http://dx.doi.org/10.1039/d1tc03782j.

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Green solvent additives were employed as non-solvents in binary solvent systems to enable the pre-aggregation of organic semiconductors and enhance the electrical performance of organic field-effect transistors and complementary-like inverters.

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Dhum, Pranali, Minakshi Nehete, and Rajesh Maheshwari. "NOVEL ECOFRIENDLY TECHNIQUE FOR SPECTROPHOTOMETRIC ANALYSIS OF DICLOFENAC SODIUM TABLETS USING MELTED N, N- DIMETHYLUREA AS SOLID SOLVENT." Indian Drugs 59, no. 04 (June 1, 2022): 46–50. http://dx.doi.org/10.53879/id.59.04.12403.

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Commonly used organic solvents for spectrophotometric analysis of water insoluble drugs include alcohol, chloroform, benzene, methylene chloride, dimethyl formamide, acetonitrile, toluene, acetone and hexane. The main drawbacks of organic solvents are high value, toxicity and pollution. Hence, it is essential to replace the organic solvents by other eco-friendly alternative sources. Hydrotropic solubilization technique is the best approach to increase the water solubility of poorly water-soluble drugs and overcome the problems related with organic solvents. The present investigation is an attempt to show application of hydrotropic technique using aqueous solutions of N, N-dimethylurea as a hydrotropic agent for extraction of a poorly water soluble drug, diclofenac sodium, from its tablet formulation. The present research work also provides an ecofriendly method to estimate spectrophotometrically the diclofenac sodium drug in tablet formulations without help of an organic solvent. Proposed spectrophotometric method was found to be novel, accurate, economic, ecofriendly and free from toxicity of organic solvent.

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Sarwono, Rakhman, Saepulloh Saepulloh, Brayen Brayen, Andreas Andreas, and Yeyen Maryani. "Degradation of Oil Palm Empty Fruit Bunch (OPEFB) in Super-Critical Organic Solvents Affecting the Chemicals Distribution of Bio-Oil." Jurnal Kimia Terapan Indonesia 19, no. 2 (January 25, 2018): 62–72. http://dx.doi.org/10.14203/jkti.v19i2.357.

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Hydrothermal liquefaction (HTL) of oil palm empty fruit bunch (OPEFB) in different organic solvents (methanol, ethanol, acetone, toluene and hexane) to produce bio-oil were comparatively investigated. Experiments were carried out in an autoclave at different temperature of 300, 350 and 400 oC with a fixed solid/liquid ratio of 4 gram in 50 mL solvent, without catalysts and reaction time of 5 hours. The liquid products were analyzed using GCMS to determine the chemical composition. Result showed that the chemical compositions were greatly affected by the solvent types. Each solvent has a major component in bio-oil products. The major compounds resulted from methanol and ethanol solvent were ketones/others. The major compounds resulted from toluene and hexane solvents were organic acid, which favoured high temperature. Meanwhile, esters and organic acid were the major products from acetone solvents. Temperature operation resulted more variations in the chemical composition and the percentages of the bio-oil.

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Maheu, Maxime, François Champoux, and Adrian Fuente. "Acute Vertigo in a Patient with Long-Term Organic Solvent Exposure: Importance of a Comprehensive Audio-Vestibular Test Battery." Journal of the American Academy of Audiology 31, no. 05 (May 2020): 363–68. http://dx.doi.org/10.3766/jaaa.19034.

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Abstract Background Ototoxicity induced by organic solvents has been identified in several groups of workers. Little is known, however, about the effects of organic solvents on the vestibular system. Purpose The aim of the study was to comprehensively assess the vestibular system and auditory functions in a worker exposed to organic solvents. Research Design Both behavioral and physiological auditory and vestibular evaluations were performed. Results No auditory-related findings associated with solvent exposure were found. The vestibulo-ocular reflex gain was abnormal for all semicircular canals with significant catch-up saccades, as measured by the video head impulse test. The cervical vestibular evoked myogenic potentials was absent in the right ear and small but replicable in the left ear. Ocular vestibular evoked myogenic potential were bilaterally absent. Conclusions The results suggest a case of vestibulotoxicity induced by a long history of organic solvent exposure. We suggest that solvent-exposed individuals should be evaluated with a comprehensive battery of auditory and vestibular tests.

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Jeong, Mijeong Lee, Michael Zahn, Thao Trinh, Qi Jia, and Wenwen Ma. "Headspace Gas ChromatographyFlame Ionization Detector Method for Organic Solvent Residue Analysis in Dietary Supplements." Journal of AOAC INTERNATIONAL 89, no. 6 (November 1, 2006): 1475–82. http://dx.doi.org/10.1093/jaoac/89.6.1475.

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Abstract An analytical method has been developed for the identification and quantification of 20 organic solvent residues in dietary supplements. The method utilizes a headspace sampler interfaced with gas chromatography and flame ionization detection. With split injection (5:1) and a DB-624 column, most of the organic solvents are separated in 9 min. The method has been validated and was found to be relatively simple and fast, and it can be applied to most common organic solvent residues. With the mass detector, the method was able to identify organic solvents beyond the 20 standards tested.

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Shin, Paik-Kyun, Palanisamy Kumar, Abhirami Kumar, Santhakumar Kannappan, and Shizuyasu Ochiai. "Effects of Organic Solvents for Composite Active Layer of PCDTBT/PC71BM on Characteristics of Organic Solar Cell Devices." International Journal of Photoenergy 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/786468.

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Bulk heterojunction (BHJ) structure based active layers of PCDTBT/PC71BM were prepared by using different organic solvents for fabrication of organic solar cell (OSC) devices. Mixture of precursor solutions of PCDTBT/PC71BM in three different organic solvents was prepared to fabricate composite active layers by spin-coating process: chloroform; chlorobenzene; o-dichlorobenzene. Four different blend ratios (1 : 3–1 : 6) of PCDTBT: PC71BM were adopted for each organic solvent to clarify the effect on the resulting OSC device characteristics. Surface morphology of the active layers was distinctively affected by the blend ratio of PCDTBT/PC71BM in organic solvents. Influence of the blend ratio of PCDTBT/PC71BM on the OSC device parameters was discussed. Performance parameters of the resulting OSC devices with different composite active layers were comparatively investigated. Appropriate blend ratio and organic solvent to achieve better OSC device performance were proposed. Furthermore, from the UV-Vis spectrum of each active layer prepared using the PCDTBT/PC71BM mixed solution dissolved with different organic solvents, a possibility that the nanophase separation structure inside their active layer could appear was suggested.

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Gan, Ruolong, Junrong Li, Xiuhua Cao, Jun Huang, and Liying Qian. "Mixed Solvents in Multilayer Ceramic Capacitors (MLCC) Electronic Paste and Their Effects on the Properties of Organic Vehicle." Polymers 14, no. 4 (February 11, 2022): 685. http://dx.doi.org/10.3390/polym14040685.

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The copper end paste used in multilayer ceramic capacitors sintered in nitrogen atmosphere leads to carbon residues of organic vehicles, which leads to a reduction in electrode conductivity and high scrap rate. With an attempt to leave no residue in the sintering, the compatibility of solvents and thickeners should be improved because it has an important influence on the hierarchical volatilization and carbon residue of organic vehicles. In this work, the volatility of different solvents was compared, and several solvents were mixed in a definite proportion to prepare an organic vehicle with polyacrylate resins. The hierarchical volatility and solubility parameters of mixed solvents were effectively adjusted by changing proportions of different components. The thermogravimetric curves of resins and organic vehicles were measured by thermogravimetric analyzer, and the effect of solubility parameter on the dissolvability of resins in the solvent and the residual of organic vehicles were studied. Results showed that the hierarchical volatilization of solvents can be obtained by mixing different solvents; the intrinsic viscosity of the organic vehicle is higher, and the thermal decomposition residue of polyacrylate resins is lower when the solubility parameters of mixed solvents and polyacrylate resins are closer. The low residual sintering of organic vehicles can be achieved by using a mixed solvent with hierarchical volatility and approximate solubility parameters as resins.

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Sharma, Shivika, and Shamsher S. Kanwar. "Organic Solvent Tolerant Lipases and Applications." Scientific World Journal 2014 (2014): 1–15. http://dx.doi.org/10.1155/2014/625258.

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Lipases are a group of enzymes naturally endowed with the property of performing reactions in aqueous as well as organic solvents. The esterification reactions using lipase(s) could be performed in water-restricted organic media as organic solvent(s) not only improve(s) the solubility of substrate and reactant in reaction mixture but also permit(s) the reaction in the reverse direction, and often it is easy to recover the product in organic phase in two-phase equilibrium systems. The use of organic solvent tolerant lipase in organic media has exhibited many advantages: increased activity and stability, regiospecificity and stereoselectivity, higher solubility of substrate, ease of products recovery, and ability to shift the reaction equilibrium toward synthetic direction. Therefore the search for organic solvent tolerant enzymes has been an extensive area of research. A variety of fatty acid esters are now being produced commercially using immobilized lipase in nonaqueous solvents. This review describes the organic tolerance and industrial application of lipases. The main emphasis is to study the nature of organic solvent tolerant lipases. Also, the potential industrial applications that make lipases the biocatalysts of choice for the present and future have been presented.

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Ahmed, Sofia, Nafeesa Mustaan, Muhammad Ali Sheraz, Syeda Ayesha Ahmed un Nabi, and Iqbal Ahmad. "Validation of a UV Spectrometric Method for the Assay of Tolfenamic Acid in Organic Solvents." Journal of Pharmaceutics 2015 (December 10, 2015): 1–8. http://dx.doi.org/10.1155/2015/216249.

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The present study has been carried out to validate a UV spectrometric method for the assay of tolfenamic acid (TA) in organic solvents. TA is insoluble in water; therefore, a total of thirteen commonly used organic solvents have been selected in which the drug is soluble. Fresh stock solutions of TA in each solvent in a concentration of 1 × 10−4 M (2.62 mg%) were prepared for the assay. The method has been validated according to the guideline of International Conference on Harmonization and parameters like linearity, range, accuracy, precision, sensitivity, and robustness have been studied. Although the method was found to be efficient for the determination of TA in all solvents on the basis of statistical data 1-octanol, followed by ethanol and methanol, was found to be comparatively better than the other studied solvents. No change in the stock solution stability of TA has been observed in each solvent for 24 hours stored either at room (25±1°C) or at refrigerated temperature (2–8°C). A shift in the absorption maxima has been observed for TA in various solvents indicating drug-solvent interactions. The studied method is simple, rapid, economical, accurate, and precise for the assay of TA in different organic solvents.

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Alvarez, Guillermo A., Wolfram Baumann, Martha Bohrer Adaime, and Frank Neitzel. "The Solubility of Organic Compounds in Supercritical CO2." Zeitschrift für Naturforschung A 60, no. 8-9 (September 1, 2005): 641–48. http://dx.doi.org/10.1515/zna-2005-8-915.

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A simple liquid solution model is proposed to describe the effect of solvent-solute interactions on the solubility of nonpolar and slightly polar substances in supercritical solvents. Treating the system as an ideal solution, the effect of pressure on the solubility is zero or nearly zero, as it is governed by the difference in molar volume of the pure supercooled liquid solute and the pure solid solute, and this may be nearly zero. Deviations from ideal behavior are given by activity coefficients of the Margules type with the interaction parameter w interpreted as interchange energy as in the lattice theory. The hypothesis is put forward that the interchange energy is of the same form as a function proposed by Liptay and others to describe the effect of the solvent on the wavelength of the absorption maximum of the solute dissolved in the solvent. The function consists of a radius of interaction a and a function g(ε ) of the dielectric constant ε of the solvent, treated as a continuum. The function g depends on pressure through the pressure dependence of the dielectric constant ε (P). The attractive feature of this formalism, introduced by Baumann et al. and here justified thermodynamically, is that plots of the logarithm of solubility vs. g are linear, except for polar solutes near the solvent’s critical point. Changes in slope then admit interpretation as changes in the radius of interaction a with possible clues about the mechanism of solvation of these molecules.

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Tähti, Hanna. "The Neurotoxicity of Organic Solvents, Studied with in Vitro Models." Alternatives to Laboratory Animals 20, no. 2 (April 1992): 290–96. http://dx.doi.org/10.1177/026119299202000221.

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The present paper deals with the general anaesthetic effect of organic solvents. The emphasis is on cell membranes as models for predicting the adverse reactions of the human nervous system to organic solvents, and for studying the mechanisms of their anaesthetic action. Human and rat erythrocyte and platelet membranes, rat synaptosomal membranes and cultured neural cell membranes were exposed in vitro to various concentrations (3–30mM) of benzene, toluene, o-xylene and styrene in the incubation mixtures. After exposure to a solvent for 30 minutes, the membrane integral protein integrity was determined by measuring ATPase and acetylcholinesterase activities. All measurements were performed in triplicate from 3 or 4 independent experiments with each exposure of solvent and each membrane isolation. The enzyme inhibition was dose-dependent, and differed after solvent treatment in all membrane preparations tested in increasing order, as follows: benzene, toluene, styrene, o-xylene. The results support the protein theories on the mechanism of the anaesthetic action of various industrial organic solvents. The integral membrane proteins contain hydrophobic pockets which may bind anaesthetics, e.g. solvents which change the properties of integral enzymes. The effects of solvents in peripheral models are quite similar to those in neural membranes in vitro. Therefore, these membrane models can serve as test models when the narcotic potencies of the solvents are being evaluated, or at least for screening purposes and for studies of the mechanisms of solvent neurotoxicity.

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Ou, Guangnan, Biyan He, Xuejing Li, and Jianhui Lei. "Glycerol Carbonate: A Novel Biosolvent with Strong Ionizing and Dissociating Powers." Scientific World Journal 2012 (2012): 1–6. http://dx.doi.org/10.1100/2012/697161.

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The activity of biocatalysts in nonaqueous solvents is related to the interaction of organic solvents with cells or enzymes. The behavior of proteins is strongly dependent on the protonation state of their ionizable groups, which ionization constants are greatly affected by the solvent. Due to the weak ionizing and dissociating powers of common organic solvents, the charge of the protein will change significantly when the protein is transferred from water to common organic solvents, resulting in protein denaturation. In this work, glycerol carbonate (GC) was synthesized, which ionizing and dissociating abilities were very close to those of water. Transesterification activities ofCandida antarcticalipase B (CALB) in GC were comparable to those in water and remained constant during 4-week storage.Bacillus subtilisandSaccharomyecs cerevisiaewere cultured in liquid media containing GC with test tubes. In the medium containing low GC concentration,Bacillus subtilisandSaccharomyecs cerevisiaegrew well as in a medium containing no organic solvent, but, in the medium containing high GC concentration, the growth ofBacillus subtilisandSaccharomyecs cerevisiaewas suppressed. The results suggested that GC is a potential biosolvent, which has great significance to biocatalysis in nonaqueous solvents.

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35

Taghavi, Toktam, Hiral Patel, Omololu E. Akande, and Dominique Clark A. Galam. "Total Anthocyanin Content of Strawberry and the Profile Changes by Extraction Methods and Sample Processing." Foods 11, no. 8 (April 7, 2022): 1072. http://dx.doi.org/10.3390/foods11081072.

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Anthocyanins are the primarily pigments in many flowers, vegetables, and fruits and play a critical role in human and plant health. They are polyphenolic pigments that are soluble in water and usually quantified by spectrophotometric methods. The two main methods that quantify anthocyanins are pH differential and organic solvent-based methods. Our hypothesis was that these methods extract different anthocyanin profiles. Therefore, this experiment was designed to identify anthocyanin profiles that are extracted by pH differential and organic solvent-based methods and observe their total anthocyanin content from strawberries. Six methods were tested in this experiment to quantify and profile anthocyanins in strawberry fruits by spectrophotometry and Ultra High Performance Liquid Chromatography (UHPLC) respectively. Four methods used organic solvents (methanol, and chloroform-methanol) in different combinations. The next two methods were pH differential and a combination of organic solvent and the pH differential method. The results suggest that acidified chloroform-methanol extracted the highest anthocyanin content compared to water-based solvents. Methanol-water based solvents also performed better than methanol alone, because both methanol and water may extract different profiles of anthocyanins. Water-based extracts had the greatest absorbance at a lower wavelength (498 nm), followed by methanol (508 nm), and chloroform (530 nm). Chloroform-methanol solvent with higher pH (3.0) extracted pelargonidin as the main anthocyanin, while methanol and water-based solvents (with lower pH 1.0–2.0) extracted delphinidin as their main anthocyanin as identified by UHPLC. Therefore, chloroform-methanol and methanol-water solvents were the best solvents for extracting anthocyanins from strawberries. Also, freeze-dried strawberries had higher anthocyanin contents compared to fresh or frozen samples.

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Jalan, Ishita, Lisa Lundin, and Jan van Stam. "Using Solubility Parameters to Model More Environmentally Friendly Solvent Blends for Organic Solar Cell Active Layers." Materials 12, no. 23 (November 25, 2019): 3889. http://dx.doi.org/10.3390/ma12233889.

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To facilitate industrial applications, as well as for environmental and health purposes, there is a need to find less hazardous solvents for processing the photoactive layer of organic solar cells. As there are vast amounts of possibilities to combine organic solvents and solutes, it is of high importance to find paths to discriminate among the solution chemistry possibilities on a theoretical basis. Using Hansen solubility parameters (HSP) offers such a path. We report on some examples of solvent blends that have been found by modelling HSP for an electron donor polymer (TQ1) and an electron acceptor polymer (N2200) to match solvent blends of less hazardous solvents than those commonly used. After the theoretical screening procedure, solubility tests were performed to determine the HSP parameters relevant for the TQ1:N2200 pair in the calculated solvent blends. Finally, thin solid films were prepared by spin-coating from the solvent blends that turned out to be good solvents to the donor-acceptor pair. Our results show that the blend film morphology prepared in this way is similar to those obtained from chloroform solutions.

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Fuente, A., and B. McPherson. "<p>Organic solvents and hearing loss: The challenge for audiology</p>." Community Ear and Hearing Health 3, no. 4 (December 1, 2006): 8. http://dx.doi.org/10.56920/cehh.189.

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Organic solvents have been reported to adversely affect human health, including hearing health. Animal models have demonstrated that solvents may induce auditory damage, especially to the outer hair cells. Research on workers exposed to solvents has suggested that these chemicals may also induce auditory damage through effects on the central auditory pathways. Studies conducted with both animals and humans demonstrate that the hearing frequencies affected by solvent exposure are different to those affected by noise, and that solvents may interact synergistically with noise. The present article aims to review the contemporary literature of solvent-induced hearing loss, and consider the implications of solvent-induced auditory damage for clinical audiologists. Possible audiological tests that may be used when auditory damage due to solvent exposure is suspected are discussed. Published Courtesy of:Int J Audiol. 2006; 45 (7): 367-381

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Cardea, Stefano, and Ernesto Reverchon. "Supercritical Fluid Processing of Polymers." Polymers 11, no. 10 (September 24, 2019): 1551. http://dx.doi.org/10.3390/polym11101551.

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The use of supercritical fluids instead of organic solvents has attracted the interest of numerous researchers, due to the unique peculiarities of supercritical fluids which are characterized by solvent powers comparable to those of liquid organic solvents, diffusivity comparable to those of gaseous substances and quasi-zero surface tension [...]

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Shi, Yu Kun, Guang Fei Qu, Ping Ning, Jun Zhang, and Hui Feng. "Advances of Application of Ionic Liquids in Catalytic Oxidation Reactions." Advanced Materials Research 233-235 (May 2011): 499–506. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.499.

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Advances of application of ionic liquids as solvents and catalysts in the catalytic oxidation reaction are summarized in this paper. Ionic liquids, as solvent, can provide an environment which is different from the traditional organic solvents for the chemical reactions, and make the catalytic activity and stability better, conversion and selectivity higher; Ionic liquids, as catalyst, not only play the function of promoting reaction, but also play a solvent/catalyst dual functions more directly. Currently ionic liquids in catalytic oxidation reaction are mostly used as solvent, Especially used widely in organic synthesis. The designability of ionic liquids provides a broad space for ionic liquids as catalyst.

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40

Guthrie, O’neil W., Brian A. Wong, Shawn M. McInturf, James E. Reboulet, Pedro A. Ortiz, and David R. Mattie. "Background Noise Contributes to Organic Solvent Induced Brain Dysfunction." Neural Plasticity 2016 (2016): 1–11. http://dx.doi.org/10.1155/2016/8742725.

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Occupational exposure to complex blends of organic solvents is believed to alter brain functions among workers. However, work environments that contain organic solvents are also polluted with background noise which raises the issue of whether or not the noise contributed to brain alterations. The purpose of the current study was to determine whether or not repeated exposure to low intensity noise with and without exposure to a complex blend of organic solvents would alter brain activity. Female Fischer344 rats served as subjects in these experiments. Asynchronous volume conductance between the midbrain and cortex was evaluated with a slow vertex recording technique. Subtoxic solvent exposure, by itself, had no statistically significant effects. However, background noise significantly suppressed brain activity and this suppression was exacerbated with solvent exposure. Furthermore, combined exposure produced significantly slow neurotransmission. These abnormal neurophysiologic findings occurred in the absence of hearing loss and detectable damage to sensory cells. The observations from the current experiment raise concern for all occupations where workers are repeatedly exposed to background noise or noise combined with organic solvents. Noise levels and solvent concentrations that are currently considered safe may not actually be safe and existing safety regulations have failed to recognize the neurotoxic potential of combined exposures.

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Yevchuk, Iryna, Roman Makitra, Olena Pal’chykova, and Galyna Khovanets’. "Regularities of organic solvents diffusion into fluoropolymer structure." Chemistry & Chemical Technology 2, no. 1 (March 15, 2008): 7–10. http://dx.doi.org/10.23939/chcht02.01.007.

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Diffusion coefficients of organic solvents into tetrafluoroethylene-propylene copolymer structure may be generalized by multiparameter equations. Molar volume and cohesion energy of penetrating liquids are suggested to be determining their values and retarding the process.

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Serheyev, Valentyn. "Enthalpies of Mixing Methylmethacrylate with Some Organic Solvents." Chemistry & Chemical Technology 6, no. 1 (March 15, 2012): 15–18. http://dx.doi.org/10.23939/chcht06.01.015.

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43

Osadchuk, T. V., O. V. Shybyryn, A. V. Semyroz, and V. K. Kibirev. "Influence of organic solvents on the furin activity." Ukrainian Biochemical Journal 90, no. 5 (October 1, 2018): 28–33. http://dx.doi.org/10.15407/ubj90.05.028.

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Naskali, Leila, Maria Engelke, and Hanna Tähti. "The Neurotoxicity of Organic Solvents Studied Using Synaptosomes and Neural Cell Cultures." Alternatives to Laboratory Animals 22, no. 3 (May 1994): 175–79. http://dx.doi.org/10.1177/026119299402200307.

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The most common acute neurotoxic effect of organic solvents is their central nervous system (CNS) depressant effect. The molecular mechanism underlying this effect is not known. The purpose of our studies has been to evaluate the adverse effects of organic solvents on the CNS in vitro. Synaptosomal membranes, whole brain reaggregate and astrocyte cultures were studied. Our results suggest that cell membrane integral proteins are targets for solvent impact, but that there are differences among various cell types. In addition to lipophilicity, the structure of solvent molecules seems to be important when considering CNS toxicity. Organic solvents increase the fluidity of the membranes, which may disturb the lipid-protein interaction and the optimal functioning of the enzyme. However, direct effects of solvents on proteins cannot be excluded. In vitro cell models can be used in methods designed to predict acute neurotoxic effects of foreign compounds, and in studies of neurotoxic mechanisms.

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Tao, Fei, Bo Yu, Ping Xu, and Cui Qing Ma. "Biodesulfurization in Biphasic Systems Containing Organic Solvents." Applied and Environmental Microbiology 72, no. 7 (July 2006): 4604–9. http://dx.doi.org/10.1128/aem.00081-06.

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ABSTRACT Biphasic systems can overcome the problem of low productivity in conventional media and have been exploited for biocatalysis. Solvent-tolerant microorganisms are useful in biotransformation with whole cells in biphasic reactions. A solvent-tolerant desulfurizing bacterium, Pseudomonas putida A4, was constructed by introducing the biodesulfurizing gene cluster dszABCD, which was from Rhodococcus erythropolis XP, into the solvent-tolerant strain P. putida Idaho. Biphasic reactions were performed to investigate the desulfurization of various sulfur-containing heterocyclic compounds in the presence of various organic solvents. P. putida A4 had the same substrate range as R. erythropolis XP and could degrade dibenzothiophene at a specific rate of 1.29 mM g (dry weight) of cells−1 h−1 for the first 2 h in the presence of 10% (vol/vol) p-xylene. P. putida A4 was also able to degrade dibenzothiophene in the presence of many other organic solvents at a concentration of 10% (vol/vol). This study is a significant step in the exploration of the biotechnological potential of novel biocatalysts for developing an efficient biodesulfurization process in biphasic reaction mixtures containing toxic organic solvents.

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Zangade, Sainath, and Pravinkumar Patil. "A Review on Solvent-free Methods in Organic Synthesis." Current Organic Chemistry 23, no. 21 (January 9, 2020): 2295–318. http://dx.doi.org/10.2174/1385272823666191016165532.

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Most of the synthetic chemical transformation reactions involve the use of different organic solvents. Unfortunately, some of these toxic solvents are used in chemical laboratory, industry and have been considered a very serious problem for the health, safety of workers and environmental damage through pollution. The purpose of green chemistry is to provide a path that reduces or eliminates the use of such hazardous toxic solvents. Therefore, the key factor of the green synthetic approach is to utilize renewable materials, nontoxic chemical and to perform the reactions under solvent-free conditions. In this review, we have discussed most recent literature survey on applications of solvent-free techniques in organic synthesis which would offer a new opportunity to a researcher to overcome the problem of using environmental harmful solvents.

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Grazinoli-Garrido, Rodrigo, and Mauro Sola-Penna. "Inactivation of yeast inorganic pyrophosphatase by organic solvents." Anais da Academia Brasileira de Ciências 76, no. 4 (December 2004): 699–705. http://dx.doi.org/10.1590/s0001-37652004000400006.

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A number of application for enzymes in organic solvents have been developed in chemical processing, food related conversions and analyses. The only unsolved problem related to nonaqueous enzymology is the notion that enzymes in organic solvent are mostly far less active than in water. Therefore, studies concerning the mechanisms by which enzymes are inactivated by organic solvents would reveal a clear understanding of the structure-function relationship of this phenomenon. Here we analyzed the effects of a series of alcohols (methanol, ethanol, 1-propanol and 2-propanol) and acetone on the activity of yeast inorganic pyrophosphatase. We observed that solvents inactivated the enzyme in a dose-dependent manner. This inactivation is also dependent on the hydrophobicity of the solvent, where the most hydrophobic solvent is also the most effective one. The I50 for inactivation by n-alcohols are 5.9±4, 2.7±1 and 2.5±1 M for methanol, ethanol and 1-propanol, respectively. Inactivation was less effective at 37C than at 5C, when the I50 for inactivation by methanol, ethanol and 1-propanol are 4.5±2, 2.1±2 and 1.7±1 M, respectively. Our proposal is that solvent binds to the enzyme structure promoting the inactivation by stabilizing an unfolded structure, and that this binding is through the hydrophobic regions of either the protein or the solvent.

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Ogino, Hiroyasu, Takeshi Uchiho, Jyunko Yokoo, Reina Kobayashi, Rikiya Ichise, and Haruo Ishikawa. "Role of Intermolecular Disulfide Bonds of the Organic Solvent-Stable PST-01 Protease in Its Organic Solvent Stability." Applied and Environmental Microbiology 67, no. 2 (February 1, 2001): 942–47. http://dx.doi.org/10.1128/aem.67.2.942-947.2001.

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ABSTRACT The PST-01 protease is secreted by the organic solvent-tolerant microorganism Pseudomonas aeruginosa PST-01 and is stable in the presence of various organic solvents. Therefore, the PST-01 strain and the PST-01 protease are very useful for fermentation and reactions in the presence of organic solvents, respectively. The organic solvent-stable PST-01 protease has two disulfide bonds (between Cys-30 and Cys-58 and between Cys-270 and Cys-297) in its molecule. Mutant PST-01 proteases in which one or both of the disulfide bonds were deleted were constructed by site-directed mutagenesis, and the effect of the disulfide bonds on the activity and the various stabilities was investigated. The disulfide bond between Cys-270 and Cys-297 in the PST-01 protease was found to be essential for its activity. The disulfide bond between Cys-30 and Cys-58 played an important role in the organic solvent stability of the PST-01 protease.

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Kim, Tae-Kyung, Jae-Hoon Lee, Hae In Yong, Min-Cheoul Kang, Ji Yoon Cha, Ji Yeon Chun, and Yun-Sang Choi. "Effects of Defatting Methods on the Physicochemical Properties of Proteins Extracted from Hermetia illucens Larvae." Foods 11, no. 10 (May 12, 2022): 1400. http://dx.doi.org/10.3390/foods11101400.

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In this study, we investigated the effects of various defatting methods, including organic solvent (aqueous, acetone, ethanol, and hexane) extraction and physical (cold pressure) extraction, on the nutritional, physicochemical, and functional properties of proteins extracted from Hermetia illucens larvae. The total essential amino acid contents were higher with cold pressure protein extraction than other treatments. The surface hydrophobicity with cold pressure treatment was the lowest, and there were no significant differences among the other treatments. The protein solubility after defatting with organic solvent was higher than for other treatments. The nonreduced protein band at 50 kDa of the defatted protein prepared using organic solvent was fainter than in the cold pressure treatment. The cold pressure-defatted protein showed the highest emulsifying capacity, and the water extracted protein showed the lowest emulsifying capacity. Although organic solvents may be efficient for defatting proteins extracted from insects, organic solvents have detrimental effects on the human body. In addition, the organic solvent extraction method requires a considerable amount of time for lipid extraction. Based on our results, using cold pressure protein extraction on edible insect proteins is ecofriendly and economical due to the reduced degreasing time and its potential industrial applications.

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Dwamena, Amos K. "Recent Advances in Hydrophobic Deep Eutectic Solvents for Extraction." Separations 6, no. 1 (February 12, 2019): 9. http://dx.doi.org/10.3390/separations6010009.

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Abstract:

In the over 1,800 articles published since their inception in 2001, most deep eutectic solvents (DES) synthesized have been hydrophilic. The low cost, low toxicity, and bioavailability of DES make the solvent ‘green’ and sustainable for diverse applications. Conversely, the hydrophilicity of DES limits their practical application to only polar compounds, which is a major drawback of the solvent. For the past three years, hydrophobic deep eutectic solvents (HDES) have emerged as an alternative extractive media capable of extracting non-polar organic and inorganic molecules from aqueous environments. Due to the infancy of HDES, for the first time, this mini-review summarizes the recent developmental advances in HDES synthesis, applications, challenges, and future perspectives of the solvent. In the future, it is believed HDES will replace the majority of toxic organic solvents used for analytical purposes.

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Journal articles on the topic 'Solventi organici'

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