Search results for: diethyl phthalate
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 55

Search results for: diethyl phthalate

55 Heterogeneous Catalytic Ozonation of Diethyl Phthalate

Authors: Chedly Tizaoui, Hussain Mohammed, Lobna Mansouri, Nidal Hilal, Latifa Bousselmi

Abstract:

The degradation of diethyl phthalate (DEP) was studied using heterogeneous catalytic ozonation. Activated carbon was used as a catalyst. The degradation of DEP with ozone alone was slow while catalytic ozonation increased degradation rates. Second-order reaction kinetics was used to describe the experimental data, and the corresponding rate constant values were 1.19 and 3.94 M-1.s-1 for ozone and ozone/activated carbon respectively.

Keywords: ozone, heterogeneous catalytic ozonation, diethyl phthalate, endocrine disrupting chemicals

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54 Biodegradation Study of Diethyl Phthalate Using Bacteria Isolated from Plastic Industry Wastewater Discharge Site

Authors: Sangram Shamrao Patil, Hara Mohan Jena

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Phthalates are among the most common organic pollutant since they have become widespread in the environment and found in sediments, natural waters, soils, plants, landfill leachates, biota including human tissue and aquatic organisms. Diethyl phthalate (DEP) is a low molecular weight phthalate which has wide applications as plasticizer and become a major cause of environmental pollution. Environmental protection agency (EPA) listed DEP as priority pollutant because of its toxicity and they recommended human health ambient water quality criterion for diethyl phthalate (DEP) as 4 mg/l. Therefore, wastes containing phthalates require proper treatment before being discharged into the environment. Biodegradation is attractive and efficient treatment method as it is cost effective and produces non-toxic end products. In the present study, a DEP degrading aerobic bacterium was isolated from soil contaminated with plastic industry wastewater. Morphological and biochemical characteristics of isolate were performed. 16S rRNA sequencing and phylogenetic analysis of isolate was carried out and it was identified as Empedobacter brevis. Isolate has been found to tolerate up to 1650 mg/l of DEP. This study will be significant for exploring an application of microbes for remediation of phthalates and development of a suitable bioreactor.

Keywords: diethyl phthalate, plasticizer, pollutant, biodegradation

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53 Phthalate Exposure among Roma Population in Slovakia

Authors: Miroslava Šidlovská, Ida Petrovičová, Tomáš Pilka, Branislav Kolena

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Phthalates are ubiquitous environmental pollutants well-known because of their endocrine disrupting activity in human organism. The aim of our study was, by biological monitoring, investigate exposure to phthalates of Roma ethnicity group i.e. children and adults from 5 families (n=29, average age 11.8 ± 7.6 years) living in western Slovakia. Additionally, we analysed some associations between anthropometric measures, questionnaire data i.e. socio-economic status, eating and drinking habits, practise of personal care products and household conditions in comparison with concentrations of phthalate metabolites. We used for analysis of urine samples high performance liquid chromatography and tandem mass spectrometry (HPLC-MS/MS) to determine concentrations of phthalate metabolites monoethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), mono-iso-butyl phthalate (MiBP), mono(2-ethyl-5-hydroxyhexyl) phthalate (5OH-MEHP), mono(2-ethyl-5-oxohexyl) phthalate (5oxo-MEHP) and mono(2-etylhexyl) phthalate (MEHP). Our results indicate that ethnicity, lower socioeconomic status and different housing conditions in Roma population can affect urinary concentration of phthalate metabolites.

Keywords: biomonitoring, ethnicity, human exposure, phthalate metabolites

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52 Continuous Catalytic Hydrogenation and Purification for Synthesis Non-Phthalate

Authors: Chia-Ling Li

Abstract:

The scope of this article includes the production of 10,000 metric tons of non-phthalate per annum. The production process will include hydrogenation, separation, purification, and recycling of unprocessed feedstock. Based on experimental data, conversion and selectivity were chosen as reaction model parameters. The synthesis and separation processes of non-phthalate and phthalate were established by using Aspen Plus software. The article will be divided into six parts: estimation of physical properties, integration of production processes, purification case study, utility consumption, economic feasibility study and identification of bottlenecks. The purities of products was higher than 99.9 wt. %. Process parameters have important guiding significance to the commercialization of hydrogenation of phthalate.

Keywords: economic analysis, hydrogenation, non-phthalate, process simulation

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51 Investigating the Rate of Migration of Plasticizers from PET Bottles into Salad Oil during Storage

Authors: Simin Asadollahi, Amir H. Soruri, Ali Moghimi

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Nowadays, salad oils are used in many countries around the world. Therefore, it is of great importance to ensure the safety of these food products which are usually packaged in Polyethylene terephthalate (PET) bottles and come on the market. This study investigated the effects of storage time and temperature on the migration rate of phthalate compounds from PET bottle to salad oil. In more detail, migration rate of bis (2-ethylhexyl) phthalate from bottles to salad oil samples was measured in 1st, the 30th, and the 60th days of storage at a temperature of either 20 or 40 °C. At both storage temperatures, an increase in the storage time led to a statistically significant increase in the migration rate of phthalate compounds (p<.01). Regarding this, the highest migration rate occurred after 60 days of storage in to the samples. Furthermore, it was revealed bis (2-ethylhexyl) phthalate had a higher migration rate at 40 °C than at 20 °C which showed that an increase in the storage temperature would lead to an increase in the migration rate. The highest migration rate occurred in relation to salad oil stored at 40 °C and after 60 days of storage.

Keywords: salad oil, migration rate, polyethylene terephthalate, bis (2-ethylhexyl) phthalate

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50 Evaluation of Phthalates Contents and Their Health Effects in Consumed Sachet Water Brands in Delta State, Nigeria

Authors: Edjere Oghenekohwiroro, Asibor Irabor Godwin, Uwem Bassey

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This paper determines the presence and levels of phthalates in sachet and borehole water source in some parts of Delta State, Nigeria. Sachet and borehole water samples were collected from seven different water packaging facilities and level of phthalates determined using GC-MS instrumentation. Phthalates concentration in borehole samples varied from 0.00-0.01 (DMP), 0.06-0.20 (DEP), 0.10-0.98 (DBP), 0.21-0.36 (BEHP), 0.01-0.03 (DnOP) µg/L and (BBP) was not detectable; while sachet water varied from 0.03-0.95 (DMP), 0.16-12.45 (DEP), 0.57-3.38 (DBP), 0.00-0.03 (BBP), 0.08-0.31 (BEHP) and 0-0.03 (DnOP) µg/L. Phthalates concentration in the sachet water was higher than that of the corresponding boreholes sources and also showed significant difference (p < 0.05) between the two. Sources of these phthalate esters were the interaction between water molecules and plastic storage facilities. Although concentration of all phthalate esters analyzed were lower than the threshold limit value(TLV), over time storage of water samples in this medium can lead to substantial increase with negative effects on individuals consuming them.

Keywords: phthalate esters, borehole, sachet water, sample extraction, gas chromatography, GC-MS

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49 Simultaneous Determination of Bisphenol a, Phtalates and Its Metabolites in Human Urine, by Tandem SPE Coupled to GC-MS

Authors: L. Correia-Sá, S. Norberto, Conceição Calhau, C. Delerue-Matos, V. F. Domingues

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Endocrine disruptor chemicals (EDCs) are synthetic compounds that even though being initially designed for a specific function are now being linked with a wide range of side effects. The list of possible EDCs is growing and includes phthalates and bisphenol A (BPA). Phthalates are one of the most widely used plasticizers to improve the extensibility, elasticity and workability of polyvinyl chloride (PVC), polyvinyl acetates, etc. Considered non-toxic and harmless additives for polymers, they were used unrestrainedly all over the world for several decades. However, recent studies have indicated that some phthalates and their metabolic products are reproductive and developmental toxicants in animals and suspected endocrine disruptors in humans. BPA (2,2-bis(4-hydroxyphenyl)propane) is a high production volume chemical mainly used in the production of polycarbonate plastics and epoxy resins. Although BPA was initially considered to be a weak environmental estrogen, nowadays it is known that this compound can stimulate several cellular responses at very low levels of concentrations. The aim of this study was to develop a method based on tandem SPE to evaluate the presence of phthalates, metabolites and BPA in human urine samples. The analyzed compounds included: dibutyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP), BPA, mono-isobutyl phthalate (MiBP), monobutyl phthalate (MBP) and. mono-(2-ethyl-5-oxohexyl) (MEOHP). Two SPE cartridges were applied both from Phenomenex, the strata X polymeric reversed phase and the strata X A (Strong anion). Chromatographic analyses were carried out in a Thermo GC ULTRA GC-MS/MS. Good recoveries and linear calibration curves were obtained. After validation, the methodology was applied to human urine samples for phthalates, metabolites and BPA evaluation.

Keywords: Bisphenol A (BPA), gas chromatography, metabolites, phtalates, SPE, tandem mode

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48 Bi-Functional Natural Carboxylic Acid Catalysts for the Synthesis of Diethyl α-Aminophosphonates in Aqueous Media

Authors: Hellal Abdelkader, Chafaa Salah, Boudjemaa Fouzia

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A new, convenient, and high yielding procedure for the preparation of diethyl α-aminophosphonates in water via Kabachnik-Fields reaction by one-pot reaction of aromatic aldehydes, ortho-aminophenols, and dialkylphosphites in the presence of a low catalytic amount of citric, malic, tartaric, and oxalic acids as a natural, bi-functional, and highly stable catalyst is described, the obtained products were characterized by elemental analyses, molar conductance, magnetic susceptibility, FTIR, Uv-Vis spectral data, NMR-C, NMR-H, and NMR-P analyses.

Keywords: α-aminophosphonates, aminophenols, natural acids, aqueous media, Kabachnik-Fields reaction

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47 The Hydrolysis of Phosphate Esters Can Be Enhanced by Intramolecular Hydrogen Bonding

Authors: Mohamed S. Sasi

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The research project aim is to study the hydrolysis of 8-diethylphosphate-1-naphthalenol with hydroxylamine in water. 8-diethylphosphate-1-naphthalenol, 1 was successfully synthesized and its rate of reaction with hydroxylamine was studied at 60°C. Pseudo first order behavior was observed. The rate of P-O cleavage of 1 at 60°C (7.43 x 10-3 M-1s-1) was found to be 178 fold and 7 fold slower than diethyl 8-dimethylamino-1-naphthyl phosphate, 3 at 60°C (1.32 M-1s-1) and diethyl 8-amino-1-naphthyl phosphate, 2 at 90 °C (5.5 x 10-2 M-1s-1) respectively. The rate of P-O cleavage of 1 with hydroxylamine was found to be faster than that of 4-chlorophenyl-1-cyclopropylphosphate triester, 5 where the reaction was too slow to observe at 60°C.

Keywords: phosphate esters, intramolecular hydrogen bonding

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46 Flavonoids and Phenolic Acids from the Aerial Parts of Alyssum alyssoides

Authors: Olga St. Tsiftsoglou, Diamanto M. Lazari, Eugene L. Kokkalou

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Most of Alyssum species of Brassicaceae family have been mainly studied for their contribution in ecology. In this study, A. alyssoides was examined for its chemical substitutes. The methanol extract of its aerial parts was fractionated with liquid-liquid extraction (distribution) with four different solvents of increasing polarity: diethyl ether, ethyl acetate, 1-butanol and water. The diethyl ether and ethyl acetate extracts were further studied for their chemical composition. So far, secondary metabolites which belong to phenolics were isolated by using several chromatographic methods (C.C. and HPLC) and were identified by using spectroscopic methods (UV/Vis, NMR and MS): two phenolic acids (p-hydroxy-benzoic acid and 3-methoxy-4-hydroxy-benzoic acid (vanillic acid)), and five flavonoids, which are derivatives of flavonol: kaempferol 3-O-β-D-glucopyranoside (astragalin), kaempferol 3-O-(6′′-α-L-rhamnopyranosyl)-β-D-glucopyranoside (nicotiflorin), quercetin 3-O-β-D-glucopyranoside (isoquercetin), isorhamnetin-3-O-β-D-glucopyranoside, and isoramnetin 3-O-(6′′-α-L-rhamnopyranosyl)-β-D-glucopyranoside (narcissin).

Keywords: Alyssum, chemical substitutes, flavonoids, phenolic acids

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45 Effect of Phthalates on Male Infertility: Myth or Truth?

Authors: Rashmi Tomar, A. Srinivasan, Nayan K. Mohanty, Arun K. Jain

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Phthalates have been used as additives in industrial products since the 1930s, and are universally considered to be ubiquitous environmental contaminants. The general population is exposed to phthalates through consumer products, as well as diet and medical treatments. Animal studies showing the existence of an association between some phthalates and testicular toxicity have generated public and scientific concern about the potential adverse effects of environmental changes on male reproductive health. Unprecedented declines in fertility rates and semen quality have been reported during the last half of the 20th century in developed countries and increasing interest exists on the potential relationship between exposure to environmental contaminants, including phthalates, and human male reproductive health Studies. Phthalates may be associated with altered endocrine function and adverse effects on male reproductive development and function, but human studies are limited. The aim of the present study was detection of phthalate compounds, estimation of their metabolites in infertile & fertile male. Blood and urine samples were collected from 150 infertile patients & 75 fertile volunteers recruited through Department of Urology, Safdarjung Hospital, New Delhi. Blood have been collected in separate glass tubes from the antecubital vein of the patients, serum have been separate and estimate the phthalate level in serum samples by Gas Chromatography / Mass Spectrometry using NIOSH / OSHA detailed protocol. Urine of Infertile & Fertile Subjects was collected & extracted using solid phase extraction method, analysis by HPLC. In conclusion, to the best of our knowledge the present study based on human is first to show the presence of phthalate in human serum samples and their metabolites in urine samples. Significant differences were observed between several phthalates in infertile and fertile healthy individuals.

Keywords: Gas Chromatography, HPLC, male infertility, phthalates, serum, toxicity, urine

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44 Evaluation on Estrogenic Effects of Diisononyl Adipate (DiNA) on MCF-7 Human Breast Cancer Cell Lines

Authors: Shih-cheng Li, Ming-Yi Chung, Mei-Lien Chen

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Background: Plasticizers, such as phthalates and adipates, were substances added to a material that provided flexibility and durability to plastics such as polyvinyl chloride (PVC). Phthalates were generally recognized as an endocrine disrupter due to their estrogenic and anti-androgenic activities. Phthalates had the capacity to bind to estrogen receptors, and hence they might prolong menstrual cycles and increase the proportion of premature menopause. Recently, adipates such as di-2-ethylhexyl adipate (DEHA) and di-isononyl adipate (DiNA) had replaced phthalates and were now used for food packaging. Methods: MCF-7 cell lines were treated with di-2-ethylhexyl phthalate (DEHP), di- 2-ethylhexyl adipate (DEHA), or di-isononyl adipate (DiNA) (10-6 , 10-5 , and 10-4 mol/l), using 17β-estradiol (10-8 mol/l) as a positive control. After incubations of 24, 48, 72, and 96 hours, the cells were tested using the alamarBlue assay. Results: The alamarBlue assay revealed that cell proliferation significantly increased after treatments of DEHP and DEHA for 24 hours at a concentration of 10-6, 10-5, and 10-4 mol/l. After more than 48 hours, cell proliferations in DEHP at 10-6, 10-5, and 10-4 mol/l significantly decreased compared to the control group. Conclusions: The present study demonstrates that adipates, as well as phthalates, were capable of inducing cell proliferation. We further used MDA-MB-231 cell lines to confirm that the proliferation effect was generated through binding to estrogen receptors.

Keywords: MCF-7, phthalate, adipate, endocrine disrupter

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43 Enhanced Kinetic Solubility Profile of Epiisopiloturine Solid Solution in Hipromellose Phthalate

Authors: Amanda C. Q. M. Vieira, Cybelly M. Melo, Camila B. M. Figueirêdo, Giovanna C. R. M. Schver, Salvana P. M. Costa, Magaly A. M. de Lyra, Ping I. Lee, José L. Soares-Sobrinho, Pedro J. Rolim-Neto, Mônica F. R. Soares

Abstract:

Epiisopiloturine (EPI) is a drug candidate that is extracted from Pilocarpus microphyllus and isolated from the waste of Pilocarpine. EPI has demonstrated promising schistosomicidal, leishmanicide, anti-inflammatory and antinociceptive activities, according to in vitro studies that have been carried out since 2009. However, this molecule shows poor aqueous solubility, which represents a problem for the release of the drug candidate and its absorption by the organism. The purpose of the present study is to investigate the extent of enhancement of kinetic solubility of a solid solution (SS) of EPI in hipromellose phthalate HP-55 (HPMCP), an enteric polymer carrier. SS was obtained by the solvent evaporation methodology, using acetone/methanol (60:40) as solvent system. Both EPI and polymer (drug loading 10%) were dissolved in this solvent until a clear solution was obtained, and then dried in oven at 60ºC during 12 hours, followed by drying in a vacuum oven for 4 h. The results show a considerable modification in the crystalline structure of the drug candidate. For instance, X-ray diffraction (XRD) shows a crystalline behavior for the EPI, which becomes amorphous for the SS. Polarized light microscopy, a more sensitive technique than XRD, also shows completely absence of crystals in SS sample. Differential Scanning Calorimetric (DSC) curves show no signal of EPI melting point in SS curve, indicating, once more, no presence of crystal in this system. Interaction between the drug candidate and the polymer were found in Infrared microscopy, which shows a carbonyl 43.3 cm-1 band shift, indicating a moderate-strong interaction between them, probably one of the reasons to the SS formation. Under sink conditions (pH 6.8), EPI SS had its dissolution performance increased in 2.8 times when compared with the isolated drug candidate. EPI SS sample provided a release of more than 95% of the drug candidate in 15 min, whereas only 45% of EPI (alone) could be dissolved in 15 min and 70% in 90 min. Thus, HPMCP demonstrates to have a good potential to enhance the kinetic solubility profile of EPI. Future studies to evaluate the stability of SS are required to conclude the benefits of this system.

Keywords: epiisopiloturine, hipromellose phthalate HP-55, pharmaceuticaltechnology, solubility

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42 Chemical Composition, Antioxidant and Antimicrobial Activities of the Essential Oils of Different Pinus Species from Kosovo

Authors: Fatbardhë Kurti, Giangiacomo Beretta, Behxhet Mustafa, Fabrizio Gelmini, Avni Hajdari

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Chemical profile, antioxidant and antimicrobial activity of total and fractionated essential oils (EOs) (F1 – hexane, F2 – hexane/diethyl ether, F3 – diethyl ether) derived from five Pinus species (Pinus heldreichii, P. peuce, P. mugo, Pinus nigra, P. sylvestris), were investigated. The hydrodistilled EOs and their chromatographic fractions (direct solid phase extraction, SPE) were analysed by GC-MS and 112 compounds separated and identified. The main constituents were α-pinene, β-pinene, D-limonene, β-caryophyllene, germacrene D, bornyl acetate and 3-carene. The antioxidant activities of total EOs were lower than those of the corresponding fractions, with F2 the strongest in all cases. EOs and fractions showed different degrees of antibacterial efficacy against different microbial pathogens (moderately strong antimicrobial activity against C. albicans and C. krusei ,while low or no activity against E. faecalis and E. coli strains). The detected inhibition zones and MICs for the EOs and fractions were in the range of 14 -35 mm and 0.125 - 1% (v/v), respectively. The components responsible for the antioxidant and antimicrobial activity were oxygenated monoterpenes and sesquiterpenes recovered in the polar EO fractions. These activities seem to be regulated by reciprocal interactions among the different subclasses of phytochemical species present in the EOs.

Keywords: antagonism, antioxidant activity, antibacterial activity, essential oil, fractions, GC-MS, pinus

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41 Phthalates Exposure in Children with Central Precocious Puberty (CPP) or Constitutional Delays in Growth

Authors: Yen-An Tsai, Ching-Ling Lin, Jia-Woei Hou, Mei-Lien Chen

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Endocrine-disrupting chemicals (EDCs) adversely affect the endocrine system. Phthalates, also called phthalic acid esters (PAEs), are manmade chemicals that are used as stabilizing agents in personal care products such as perfumes, lotions, and cosmetics. The aim was to explore whether PAEs exposure was associated with central precocious puberty (CPP) or constitutional delays in growth (CDGP). This case-control study included 48 female with CPP, 37 male with constitutional delays in growth, and 127 normal children and was conducted from December 2011 to August 2014. All participants completed a structured questionnaire regarding socio-demographic characteristics, lifestyle, and secondary sexual characteristics. The analytical method was based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) with isotope dilution for the quantitative detection of several phthalate metabolites in human urine. The risk of CPP with mep, mnbp, LMW >50th percentile were higher than those with 50th percentile were higher than those with <50 percentile in model 2. In model 1, we only found higher CDGP risk in mep, mnbp, and ΣPAEs. It shows that high phthalate exposure may associate with CDGP. In this case-control study, we found PAEs exposure was associated with central precocious puberty (CPP) or constitutional delays in growth.

Keywords: phthalates, puberty, delays, growth

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40 Approach to Honey Volatiles' Profiling by Gas Chromatography and Mass Spectrometry

Authors: Igor Jerkovic

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Biodiversity of flora provides many different nectar sources for the bees. Unifloral honeys possess distinctive flavours, mainly derived from their nectar sources (characteristic volatile organic components (VOCs)). Specific or nonspecific VOCs (chemical markers) could be used for unifloral honey characterisation as addition to the melissopalynologycal analysis. The main honey volatiles belong, in general, to three principal categories: terpenes, norisoprenoids, and benzene derivatives. Some of these substances have been described as characteristics of the floral source, and other compounds, like several alcohols, branched aldehydes, and furan derivatives, may be related to the microbial purity of honey processing and storage conditions. Selection of the extraction method for the honey volatiles profiling should consider that heating of the honey produce different artefacts and therefore conventional methods of VOCs isolation (such as hydrodistillation) cannot be applied for the honey. Two-way approach for the isolation of the honey VOCs was applied using headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE). The extracts were analysed by gas chromatography and mass spectrometry (GC-MS). HS-SPME (with the fibers of different polarity such as polydimethylsiloxane/ divinylbenzene (PDMS/DVB) or divinylbenzene/carboxene/ polydimethylsiloxane (DVB/CAR/PDMS)) enabled isolation of high volatile headspace VOCs of the honey samples. Among them, some characteristic or specific compounds can be found such as 3,4-dihydro-3-oxoedulan (in Centaurea cyanus L. honey) or 1H-indole, methyl anthranilate, and cis-jasmone (in Citrus unshiu Marc. honey). USE with different solvents (mainly dichloromethane or the mixture pentane : diethyl ether 1 : 2 v/v) enabled isolation of less volatile and semi-volatile VOCs of the honey samples. Characteristic compounds from C. unshiu honey extracts were caffeine, 1H-indole, 1,3-dihydro-2H-indol-2-one, methyl anthranilate, and phenylacetonitrile. Sometimes, the selection of solvent sequence was useful for more complete profiling such as sequence I: pentane → diethyl ether or sequence II: pentane → pentane/diethyl ether (1:2, v/v) → dichloromethane). The extracts with diethyl ether contained hydroquinone and 4-hydroxybenzoic acid as the major compounds, while (E)-4-(r-1’,t-2’,c-4’-trihydroxy-2’,6’,6’-trimethylcyclo-hexyl)but-3-en-2-one predominated in dichloromethane extracts of Allium ursinum L. honey. With this two-way approach, it was possible to obtain a more detailed insight into the honey volatile and semi-volatile compounds and to minimize the risks of compound discrimination due to their partial extraction that is of significant importance for the complete honey profiling and identification of the chemical biomarkers that can complement the pollen analysis.

Keywords: honey chemical biomarkers, honey volatile compounds profiling, headspace solid-phase microextraction (HS-SPME), ultrasonic solvent extraction (USE)

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39 Characterization the Internal Corrosion Behavior by Using Natural Inhibitor in Crude Oil of Low Carbon Steel Pipeline

Authors: Iman Adnan Annon, Kadhim F. Alsultan

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This study investigate the internal corrosion of low carbon steel pipelines in the crude oil, as well as prepare and use natural and locally available plant as a natural corrosion inhibiter, the nature extraction achieved by two types of solvents in order to show the solvent effect on inhibition process, the first being distilled water and the second is diethyl ether. FT-IR spectra and using a chemical reagents achieved to detection the presence of many active groups and the presence of tannins, phenols, and alkaloids in the natural extraction. Some experiments were achieved to estimate the performance of a new inhibitor, one of these tests include corrosion measurement by simple immersion in crude oil within and without inhibitors which added in different amounts 30,40,50and 60 ppm at tow temperature 300 and 323k, where the best inhibition efficiencies which get when added the inhibitors in a critical amounts or closest to it, since for the aqueous extract (EB-A) the inhibition efficiency reached (94.4) and (86.71)% at 300 and 323k respectively, and for diethyl ether extract (EB-D) reached (82.87) and (84.6)% at 300 and 323k respectively. Optical microscopy examination have been conducted to evaluate the corrosion nature where it show a clear difference in the topography of the immersed samples surface after add the inhibitors at two temperatures. The results show that the new corrosion inhibitor is not only equivalent to a chemical inhibitor but has greatly improvement properties such as: high efficiency, low cost, non-toxic, easily to produce, and nonpolluting as compared with chemical inhibitor.

Keywords: corrosion in pipeline, inhibitors, crude oil, carbon steel, types of solvent

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38 Distribution and Risk Assessment of Phthalates in Water and Sediment of Omambala River, Anambra State, Nigeria in Wet Season

Authors: Ogbuagu Josephat Okechukwu, Okeke Abuchi Princewill, Arinze Rosemary Uche, Tabugbo Ifeyinwa Blessing, Ogbuagu Adaora Stellamaris

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Phthalates or Phthalate esters (PAEs), categorized as an endocrine disruptor and persistent organic pollutants, are known for their environmental contamination and toxicological effects. In this study, the concentration of selected phthalates was determined across the sampling site to investigate their occurrence and the ecological and health risk assessment they pose to the environment. Water and sediment samples were collected following standard procedures. Solid phase and ultrasonic methods were used to extract seven different PAEs, which were analyzed by Gas Chromatography with Mass Detector (GCMS). The analytical average recovery was found to be within the range of s83.4% ± 2.3%. The results showed that PAEs were detected in six out of seven samples with a high percentage of detection rate in water. Di-n-butyl phthalate (DPB) and diisobutyl phthalates (DiBP) showed greater detection rate compared to other PAEs monomers. The concentration of PEs was found to be higher in the sediment samples compared to the water samples due to the fact that sediments serve as a sink for most persistent organic pollutants. The concentrations of PAEs in water samples and sediments ranged from 0.03 ± 0.01 to 0.29 ± 0.002 ppm and 3.99 ± 0.43 to 6.04 ± 1.25 ppm, respectively. Ecological risk assessment using the risk quotient method (RQ) reveals that the estimated environmental risk caused by phthalates lies within the moderate level as RQ ranges from 0.1 to 1.0, whereas the health risk assessment caused by phthalates on estimating the average daily dose reveals that the ingestion of phthalates was found to be high which can cause serious carcinogenic occurrence in the human system with time due to excess accumulation.

Keywords: phthaletes, assessment, marine pollution, endocrine

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37 Phosphorous Acid: An Efficient and Recyclable Liquid Catalyst for the Synthesis of α-Aminophosphonates

Authors: Hellal Abdelkader, Chafaa Salah, Touafri Lasnouni

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A simple, efficient and general method has been developed for the high diastereoselective synthesis of diethyl α-aminophosphonates in water through “one-pot” three-component reaction of aromatic aldehydes, aminophenols and dialkyl phosphites in the presence of a low catalytic amount (10mol%) of phosphorous acid as highly stable catalyst is described.

Keywords: DFT, HOMO-LUMO, phosphonic acid, aminophenols

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36 Antimicrobial and Aroma Finishing of Organic Cotton Knits Using Vetiver Oil Microcapsules for Health Care Textiles

Authors: K. J. Sannapapamma, H. Malligawad Lokanath, Sakeena Naikwadi

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Eco-friendly textiles are gaining importance among the consumers and textile manufacturers in the healthcare sector due to increased environmental pollution which leads to several health and environmental hazards. Hence, the research was designed to cultivate and develop the organic cotton knit, to prepare and characterize the Vetiver oil microcapsules for textile finishing and to access the wash durability of finished knits. The cotton SAHANA variety grown under organic production systems was processed and spun into 30 single yarn dyed with four natural colorants (Arecanut slurry, Eucalyptus leaves, Pomegranate rind and Indigo) and eco dyed yarn was further used for development of single jersy knitted fabric. Vetiveria zizanioides is an aromatic grass which is being traditionally used in medicine and perfumery. Vetiver essential oil was used for preparation of microcapsules by interfacial polymerization technique subjected to Gas Chromatography Mass Spectrometry (GCMS), Fourier Transform Infrared Spectroscopy (FTIR), Thermo Gravimetric Analyzer (TGA) and Scanning Electron Microscope (SEM) for characterization of microcapsules. The knitted fabric was finished with vetiver oil microcapsules by exhaust and pad dry cure methods. The finished organic knit was assessed for laundering on antimicrobial efficiency and aroma intensity. GCMS spectral analysis showed that, diethyl phthalate (28%) was the major compound found in vetiver oil followed by isoaromadendrene epoxide (7.72%), beta-vetivenene (6.92%), solavetivone (5.58%), aromadenderene, azulene and khusimol. Bioassay explained that, the vetiver oil and diluted vetiver oil possessed greater zone of inhibition against S. aureus and E. coli than the coconut oil. FTRI spectra of vetiver oil and microcapsules possessed similar peaks viz., C-H, C=C & C꞊O stretching and additionally oil microcapsules possessed the peak of 3331.24 cm-1 at 91.14 transmittance was attributed to N-H stretches. TGA of oil microcapsules revealed that, there was a minimum weight loss (5.835%) recorded at 467.09°C compared to vetiver oil i.e., -3.026% at the temperature of 396.24°C. The shape of the microcapsules was regular and round, some were spherical in shape and few were rounded by small aggregates. Irrespective of methods of application, organic cotton knits finished with microcapsules by pad dry cure method showed maximum zone of inhibition compared to knits finished by exhaust method against S. aureus and E. coli. The antimicrobial activity of the finished samples was subjected to multiple washing which indicated that knits finished with pad dry cure method showed a zone of inhibition even after 20th wash and better aroma retention compared to knits finished with the exhaust method of application. Further, the group of respondents rated that the 5th washed samples had the greater aroma intensity in both the methods than the other samples. Thus, the vetiver microencapsulated organic cotton knits are free from hazardous chemicals and have multi-functional properties that can be suitable for medical and healthcare textiles.

Keywords: exhaust and pad dry cure finishing, interfacial polymerization, organic cotton knits, vetiver oil microcapsules

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35 Comparison of Processing Conditions for Plasticized PVC and PVB

Authors: Michael Tupý, Jaroslav Císař, Pavel Mokrejš, Dagmar Měřínská, Alice Tesaříková-Svobodová

Abstract:

The worldwide problem is that the recycled PVB is wildly stored in landfills. However, PVB have very similar chemical properties such as PVC. Moreover, both of them are used in plasticized form. Thus, the thermal properties of plasticized PVC obtained from primary production and the PVB was obtained by recycling of windshields are compared. It is carried out in order to find degradable conditions and decide if blend of PVB/PVC can be processable together. Tested PVC contained 38 % of plasticizer diisononyl phthalate (DINP) and PVB was plasticized with 28 % of triethylene glycol, bis(2-ethylhexanoate) (3GO). Thermal and thermo-oxidative decomposition of both vinyl polymers are compared such as DSC and OOT analysis. The tensile strength analysis is added.

Keywords: polyvinyl chloride, polyvinyl butyral, recycling, reprocessing, thermal analysis, decomposition

Procedia PDF Downloads 472
34 Mechanical Properties of Recycled Plasticized PVB/PVC Blends

Authors: Michael Tupý, Dagmar Měřínská, Alice Tesaříková-Svobodová, Christian Carrot, Caroline Pillon, Vít Petránek

Abstract:

The mechanical properties of blends consisting of plasticized poly(vinyl butyral) (PVB) and plasticized poly(vinyl chloride) (PVC) are studied, in order to evaluate the possibility of using recycled PVB waste derived from windshields. PVC was plasticized with 38% of diisononyl phthalate (DINP), while PVB was plasticized with 28% of triethylene glycol, bis(2-ethylhexanoate) (3GO). The optimal process conditions for the PVB/PVC blend in 1:1 ratio were determined. Entropy was used in order to theoretically predict the blends miscibility. The PVB content of each blend composition used was ranging from zero to 100%. Tensile strength and strain were tested. In addition, a comparison between recycled and original PVB, used as constituents of the blend, was performed.

Keywords: poly(vinyl butyral), poly(vinyl chloride), windshield, polymer waste, mechanical properties

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33 Association between Organophosphate Pesticides Exposure and Cognitive Behavior in Taipei Children

Authors: Meng-Ying Chiu, Yu-Fang Huang, Pei-Wei Wang, Yi-Ru Wang, Yi-Shuan Shao, Mei-Lien Chen

Abstract:

Background: Organophosphate pesticides (OPs) are the most heavily used pesticides in agriculture in Taiwan. Therefore, they are commonly detected in general public including pregnant women and children. These compounds are proven endocrine disrupters that may affect the neural development in humans. The aim of this study is to assess the OPs exposure of children in 2 years of age and to examine the association between the exposure concentrations and neurodevelopmental effects in children. Methods: In a prospective cohort of 280 mother-child pairs, urine samples of prenatal and postnatal were collected from each participant and analyzed for metabolites of OPs by using gas chromatography-mass spectrometry. Six analytes were measured including dimethylphosphate (DMP), dimethylthiophosphate (DMTP), dimethyldithiophosphate (DMDTP), diethylphosphate (DEP), diethylthiophosphate (DETP), and diethyldithiophosphate (DEDTP). This study created a combined concentration measure for dimethyl compounds (DMs) consisting of the three dimethyl metabolites (DMP, DMTP, and DMDTP), for diethyl compounds (DEs) consisting of the three diethyl metabolites (DEP, DETP, and DEDTP) and six dialkyl phosphate (DAPs). The Bayley Scales of Infant and Toddler Development (Bayley-III) was used to assess children's cognitive behavior at 2 years old. The association between OPs exposure and Bayley-III scale score was determined by using the Mann-Whitney U test. Results: The measurements of urine samples are still on-going. This preliminary data are the report of 56 children aged 2 from the cohort. The detection rates for DMP, DMTP, DMDTP, DEP, DETP, and DEDTP are 80.4%, 69.6%, 64.3%, 64.3%, 62.5%, and 75%, respectively. After adjusting the creatinine concentrations of urine, the median (nmol/g creatinine) of urinary DMP, DMTP, DMDTP, DEP, DETP, DEDTP, DMs, DEs, and DAPs are 153.14, 53.32, 52.13, 19.24, 141.65, 192.17, 308.8, 311.6, and 702.11, respectively. The concentrations of urine are considerably higher than that in other countries. Children’s cognitive behavior was used three scales for Bayley-III, including cognitive, language and motor. In Mann-Whitney U test, the higher levels of DEs had significantly lower motor score (p=0.037), but no significant association was found between the OPs exposure levels and the score of either cognitive or language. Conclusion: The limited sample size suggests that Taipei children are commonly exposed to OPs and OPs exposure might affect the cognitive behavior of young children. This report will present more data to verify the results. The predictors of OPs concentrations, such as dietary pattern will also be included.

Keywords: biomonitoring, children, neurodevelopment, organophosphate pesticides exposure

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32 Combined Treatment of Estrogen-Receptor Positive Breast Microtumors with 4-Hydroxytamoxifen and Novel Non-Steroidal Diethyl Stilbestrol-Like Analog Produces Enhanced Preclinical Treatment Response and Decreased Drug Resistance

Authors: Sarah Crawford, Gerry Lesley

Abstract:

This research is a pre-clinical assessment of anti-cancer effects of novel non-steroidal diethyl stilbestrol-like estrogen analogs in estrogen-receptor positive/ progesterone-receptor positive human breast cancer microtumors of MCF 7 cell line. Tamoxifen analog formulation (Tam A1) was used as a single agent or in combination with therapeutic concentrations of 4-hydroxytamoxifen, currently used as a long-term treatment for the prevention of breast cancer recurrence in women with estrogen receptor positive/ progesterone receptor positive malignancies. At concentrations ranging from 30-50 microM, Tam A1 induced microtumor disaggregation and cell death. Incremental cytotoxic effects correlated with increasing concentrations of Tam A1. Live tumor microscopy showed that microtumos displayed diffuse borders and substrate-attached cells were rounded-up and poorly adherent. A complete cytotoxic effect was observed using 40-50 microM Tam A1 with time course kinetics similar to 4-hydroxytamoxifen. Combined treatment with TamA1 (30-50 microM) and 4-hydroxytamoxifen (10-15 microM) induced a highly cytotoxic, synergistic combined treatment response that was more rapid and complete than using 4-hydroxytamoxifen as a single agent therapeutic. Microtumors completely dispersed or formed necrotic foci indicating a highly cytotoxic combined treatment response. Moreover, breast cancer microtumors treated with both 4-hydroxytamoxifen and Tam A1 displayed lower levels of long-term post-treatment regrowth, a critical parameter of primary drug resistance, than observed for 4-hydroxytamoxifen when used as a single agent therapeutic. Tumor regrowth at 6 weeks post-treatment with either single agent 4-hydroxy tamoxifen, Tam A1 or a combined treatment was assessed for the development of drug resistance. Breast cancer cells treated with both 4-hydroxytamoxifen and Tam A1 displayed significantly lower levels of post-treatment regrowth, indicative of decreased drug resistance, than observed for either single treatment modality. The preclinical data suggest that combined treatment involving the use of tamoxifen analogs may be a novel clinical approach for long-term maintenance therapy in patients with estrogen-receptor positive/progesterone-receptor positive breast cancer receiving hormonal therapy to prevent disease recurrence. Detailed data on time-course, IC50 and tumor regrowth assays post- treatment as well as a proposed mechanism of action to account for observed synergistic drug effects will be presented.

Keywords: 4-hydroxytamoxifen, tamoxifen analog, drug-resistance, microtumors

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31 Blood Chemo-Profiling in Workers Exposed to Occupational Pyrethroid Pesticides to Identify Associated Diseases

Authors: O. O. Sufyani, M. E. Oraiby, S. A. Qumaiy, A. I. Alaamri, Z. M. Eisa, A. M. Hakami, M. A. Attafi, O. M. Alhassan, W. M. Elsideeg, E. M. Noureldin, Y. A. Hobani, Y. Q. Majrabi, I. A. Khardali, A. B. Maashi, A. A. Al Mane, A. H. Hakami, I. M. Alkhyat, A. A. Sahly, I. M. Attafi

Abstract:

According to the Food and Agriculture Organization (FAO) Pesticides Use Database, pesticide use in agriculture in Saudi Arabia has more than doubled from 4539 tons in 2009 to 10496 tons in 2019. Among pesticides, pyrethroids is commonly used in Saudi Arabia. Pesticides may increase susceptibility to a variety of diseases, particularly among pesticide workers, due to their extensive use, indiscriminate use, and long-term exposure. Therefore, analyzing blood chemo-profiles and evaluating the detected substances as biomarkers for pyrethroid pesticide exposure may assist to identify and predicting adverse effects of exposure, which may be used for both preventative and risk assessment purposes. The purpose of this study was to (a) analyze chemo-profiling by Gas Chromatography-Mass Spectrometry (GC-MS) analysis, (b) identify the most commonly detected chemicals in a time-exposure-dependent manner using a Venn diagram, and (c) identify their associated disease among pesticide workers using analyzer tools on the Comparative Toxicogenomics Database (CTD) website, (250 healthy male volunteers (20-60 years old) who deal with pesticides in the Jazan region of Saudi Arabia (exposure intervals: 1-2, 4-6, 6-8, more than 8 years) were included in the study. A questionnaire was used to collect demographic information, the duration of pesticide exposure, and the existence of chronic conditions. Blood samples were collected for biochemistry analysis and extracted by solid-phase extraction for gas chromatography-mass spectrometry (GC-MS) analysis. Biochemistry analysis reveals no significant changes in response to the exposure period; however, an inverse association between the albumin level and the exposure interval was observed. The blood chemo-profiling was differentially expressed in an exposure time-dependent manner. This analysis identified the common chemical set associated with each group and their associated significant occupational diseases. While some of these chemicals are associated with a variety of diseases, the distinguishing feature of these chemically associated disorders is their applicability for prevention measures. The most interesting finding was the identification of several chemicals; erucic acid, pelargonic acid, alpha-linolenic acid, dibutyl phthalate, diisobutyl phthalate, dodecanol, myristic Acid, pyrene, and 8,11,14-eicosatrienoic acid, associated with pneumoconiosis, asbestosis, asthma, silicosis and berylliosis. Chemical-disease association study also found that cancer, digestive system disease, nervous system disease, and metabolic disease were the most often recognized disease categories in the common chemical set. The hierarchical clustering approach was used to compare the expression patterns and exposure intervals of the chemicals found commonly. More study is needed to validate these chemicals as early markers of pyrethroid insecticide-related occupational disease, which might assist evaluate and reducing risk. The current study contributes valuable data and recommendations to public health.

Keywords: occupational, toxicology, chemo-profiling, pesticide, pyrethroid, GC-MS

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30 Control of Fungal Growth in Sweet Orange and Mango Juices by Justica flava and Afromomum melegueta Extracts

Authors: Adferotimi Banso

Abstract:

A laboratory investigation was conducted to determine the effect of Justica flava and Aframonium melegueta on the growth of Aspergillus niger, Rhizopus stolonifer and Fusarium species in sweet orange and mango juices. Aqueous extract (3%v/v) of Justica flava and Aframonium melegueta reduced the growth of the fungi, a combination of 2% (v/v) each of Justica flava and Aframonium melegueta extracts reduced the growth better. Partial purification of aqueous extracts of Justica flava and Aframonium melegueta showed that ethyl acetate fraction of the extracts exhibited the highest level of inhibition of growth of the test fungi compared with diethyl ether and n-hexane fractions. The results suggest that extracts of Justica flava and Aframonium melegueta may be important substitutes for conventional chemical preservatives in the processing of fruit juices.

Keywords: aqueous, fraction, mango, orange, purification, sweet

Procedia PDF Downloads 308
29 Photophysics and Torsional Dynamics of Thioflavin T in Deep Eutectic Solvents

Authors: Rajesh Kumar Gautam, Debabrata Seth

Abstract:

Thioflavin-T (ThT) play a key role of an important biologically active fluorescent sensor for amyloid fibrils. ThT molecule has been developed a method to detect the analysis of different type of diseases such as neurodegenerative disorders, Alzheimer’s, Parkinson’s, and type II diabetes. ThT was used as a fluorescent marker to detect the formation of amyloid fibril. In the presence of amyloid fibril, ThT becomes highly fluorescent. ThT undergoes twisting motion around C-C bonds of the two adjacent benzothiazole and dimethylaniline aromatic rings, which is predominantly affected by the micro-viscosity of the local environment. The present study articulates photophysics and torsional dynamics of biologically active molecule ThT in the presence of deep-eutectic solvents (DESs). DESs are environment-friendly, low cost and biodegradable alternatives to the ionic liquids. DES resembles ionic liquids, but the constituents of a DES include a hydrogen bond donor and acceptor species, in addition to ions. Due to the presence of the H-bonding network within a DES, it exhibits structural heterogeneity. Herein, we have prepared two different DESs by mixing urea with choline chloride and N, N-diethyl ethanol ammonium chloride at ~ 340 K. It was reported that deep eutectic mixture of choline chloride with urea gave a liquid with a freezing point of 12°C. We have experimented by taking two different concentrations of ThT. It was observed that at higher concentration of ThT (50 µM) it forms aggregates in DES. The photophysics of ThT as a function of temperature have been explored by using steady-state, and picoseconds time-resolved fluorescence emission spectroscopic techniques. From the spectroscopic analysis, we have observed that with rising temperature the fluorescence quantum yields and lifetime values of ThT molecule gradually decreases; this is the cumulative effect of thermal quenching and increase in the rate of the torsional rate constant. The fluorescence quantum yield and fluorescence lifetime decay values were always higher for DES-II (urea & N, N-diethyl ethanol ammonium chloride) than those for DES-I (urea & choline chloride). This was mainly due to the presence of structural heterogeneity of the medium. This was further confirmed by comparison with the activation energy of viscous flow with the activation energy of non-radiative decay. ThT molecule in less viscous media undergoes a very fast twisting process and leads to deactivation from the photoexcited state. In this system, the torsional motion increases with increasing temperature. We have concluded that beside bulk viscosity of the media, structural heterogeneity of the medium play crucial role to guide the photophysics of ThT in DESs. The analysis of the experimental data was carried out in the temperature range 288 ≤ T = 333K. The present articulate is to obtain an insight into the DESs as media for studying various photophysical processes of amyloid fibrils sensing molecule of ThT.

Keywords: deep eutectic solvent, photophysics, Thioflavin T, the torsional rate constant

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28 Thermodynamic Properties of Binary Mixtures of 1, 2-Dichloroethane with Some Polyethers: DISQUAC Calculations Compared with Dortmund UNIFAC Results

Authors: F. Amireche, I. Mokbel, J. Jose, B. F. Belaribi

Abstract:

The experimental vapour-liquid equilibria (VLE) at isothermal conditions and excess molar Gibbs energies GE are carried out for the three binary mixtures: 1, 2- dichloroethane + ethylene glycol dimethyl ether, + diethylene glycol dimethyl ether or + diethylene glycol diethyl ether, at ten temperatures ranging from 273 to 353.15 K. A good static device was employed for these measurements. The VLE data were reduced using the Redlich-Kister equation by taking into consideration the vapour pressure non-ideality in terms of the second molar virial coefficient. The experimental data were compared to the results predicted with the DISQUAC and Dortmund UNIFAC group contribution models for the total pressures P, the excess molar Gibbs energies GE and the excess molar enthalpies HE.

Keywords: Disquac model, Dortmund UNIFAC model, 1, 2- dichloroethane, excess molar Gibbs energies GE, polyethers, VLE

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27 Phytochemical Study and Evaluation of the Antioxidant Activity of Flavonoids Isolated from Prunus persica L. Leaves

Authors: K. Fellah, H. Benmehdi, A. Amrouche, H. Malainine, F. Memmou, H. Dalile, W. Siata

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This work aims to evaluate the antioxidant of flavonoids extracted from the leaves of Prunus persica L. A phytochemical screening allowed us to highlight the different phytochemicals present in the leaves of the studied plant. The selective extraction of flavonoids gave yields of 0.71, 1.5, and 4.8% for the fractions ethyl ether, ethyl acetate and n- butanol, respectively. The reading of the antioxidant activity of different extracts of flavonoids by HPLTC method revealed positive reaction (yellow spots) on the TLC plates sprayed with DPPH. Using the DPPH method, the fractions of flavonoids (bunanol, ethyl acetate and Diethyl ether) showed a potent scavenging activity with IC50 = 0.22; 0.27 and 0.76 mg / ml, respectively. Furthermore, our findings revealed the extracts under study exhibited higher reducing potential which depends upon extract concentration. These results obtained from this investigation confirm that the Prunus persica remains a major resource of bioactive molecules.

Keywords: Prunus persica L., phytochemical study, flavonoids, antioxidant activity, TLC bioautographic, FRAP, DPPH

Procedia PDF Downloads 441
26 Synthesis of Ce Impregnated on Functionalized Graphene Oxide Nanosheets for Transesterification of Propylene Carbonate and Ethanol to Produce Diethyl Carbonate

Authors: Kumar N., Verma S., Park J., Srivastava V. C.

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Organic carbonates have the potential to be used as fuels and because of this, their production through non-phosgene routes is a thrust area of research. Di-ethyl carbonate (DEC) synthesis from propylene carbonate (PC) in the presence of alcohol is a green route. In this study, the use of reduced graphene oxide (rGO) based metal oxide catalysts [rGO-MO, where M = Ce] with different amounts of graphene oxide (0.2%, 0.5%, 1%, and 2%) has been investigated for the synthesis of DEC by using PC and ethanol as reactants. The GO sheets were synthesized by an electrochemical process and the catalysts were synthesized using an in-situ method. A theoretical study of the thermodynamics of the reaction was done, which revealed that the reaction is mildly endothermic. The theoretical value of optimum temperature was found to be 420 K. The synthesized catalysts were characterized for their morphological, structural and textural properties using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), N2 adsorption/desorption, thermogravimetric analysis (TGA), and Raman spectroscopy. Optimization studies were carried out to study the effect of different reaction conditions like temperature (140 °C to 180 °C) and catalyst dosage (0.102 g to 0.255 g) on the yield of DEC. Amongst the various synthesized catalysts, 1% rGO-CeO2 gave the maximum yield of DEC.

Keywords: GO, DEC, propylene carbonate, transesterification, thermodynamics

Procedia PDF Downloads 39