N-hexane neuropathy with vertigo and cold allodynia in a silk screen printer: A case study

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Sunil Pradhan

2015-10-01

Full Text Available N-hexane neuropathy is an occupational disease caused by exposure to n-hexane, which is used as a solvent in silk screen printing. Here, we describe a 35-year-old man, a silk screen printer by profession, who presented with dizziness, distal swelling of both lower limbs for 10 months and tingling and burning sensation in both feet for 9.5 months along with cold allodynia. The patient had normal results of a motor and sensory system examination, apart from an impaired temperature sense. Nerve conduction tests showed a conduction block in bilateral common peroneal nerves and absence of conduction in bilateral sural nerves. These symptoms resolved when further exposure to n-hexane was ceased but cold allodynia remained. Thus, cold allodynia and impaired temperature sense can be a manifestation of n-hexane neuropathy. Hence, abnormalities on nerve conduction studies can be detected in n-hexane neuropathy patients, even before clinical examination detects any such abnormalities. In the case of the patients presenting with sensory motor neuropathy, history of occupational exposure to n-hexane becomes important, as the sooner the disease is detected, the better the chances of recovery.

Communication: Molecular dynamics and {sup 1}H NMR of n-hexane in liquid crystals

Energy Technology Data Exchange (ETDEWEB)

Weber, Adrian C. J., E-mail: WeberA@BrandonU.CA [Chemistry Department, Brandon University, 270-18th Street, Brandon, Manitoba R7A 6A9 (Canada); Burnell, E. Elliott, E-mail: elliott.burnell@ubc.ca [Chemistry Department, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1 (Canada); Meerts, W. Leo, E-mail: leo.meerts@science.ru.nl [Radboud University, Institute for Molecules and Materials, Heyendaalseweg 135, NL-6525 AJ Nijmegen (Netherlands); Atomic, Molecular and Laser Physics, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam (Netherlands); Lange, Cornelis A. de, E-mail: c.a.de.lange@vu.nl [Atomic, Molecular and Laser Physics, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam (Netherlands); Dong, Ronald Y., E-mail: rondong@phas.ubc.ca [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia V6T 1Z1 (Canada); Muccioli, Luca, E-mail: Luca.Muccioli@unibo.it; Pizzirusso, Antonio, E-mail: Antonio.Pizzirusso80@gmail.com; Zannoni, Claudio, E-mail: Claudio.Zannoni@unibo.it [Dipartimento di Chimica Industriale “Toso Montanari,” Università di Bologna and INSTM, viale Risorgimento 4, 40136 Bologna (Italy)

2015-07-07

The NMR spectrum of n-hexane orientationally ordered in the nematic liquid crystal ZLI-1132 is analysed using covariance matrix adaptation evolution strategy (CMA-ES). The spectrum contains over 150 000 transitions, with many sharp features appearing above a broad, underlying background signal that results from the plethora of overlapping transitions from the n-hexane as well as from the liquid crystal. The CMA-ES requires initial search ranges for NMR spectral parameters, notably the direct dipolar couplings. Several sets of such ranges were utilized, including three from MD simulations and others from the modified chord model that is specifically designed to predict hydrocarbon-chain dipolar couplings. In the end, only inaccurate dipolar couplings from an earlier study utilizing proton-proton double quantum 2D-NMR techniques on partially deuterated n-hexane provided the necessary estimates. The precise set of dipolar couplings obtained can now be used to investigate conformational averaging of n-hexane in a nematic environment.

N-hexane neuropathy with vertigo and cold allodynia in a silk screen printer: A case study.

Science.gov (United States)

Pradhan, Sunil; Tandon, Ruchika

2015-01-01

N-hexane neuropathy is an occupational disease caused by exposure to n-hexane, which is used as a solvent in silk screen printing. Here, we describe a 35-year-old man, a silk screen printer by profession, who presented with dizziness, distal swelling of both lower limbs for 10 months and tingling and burning sensation in both feet for 9.5 months along with cold allodynia. The patient had normal results of a motor and sensory system examination, apart from an impaired temperature sense. Nerve conduction tests showed a conduction block in bilateral common peroneal nerves and absence of conduction in bilateral sural nerves. These symptoms resolved when further exposure to n-hexane was ceased but cold allodynia remained. Thus, cold allodynia and impaired temperature sense can be a manifestation of n-hexane neuropathy. Hence, abnormalities on nerve conduction studies can be detected in n-hexane neuropathy patients, even before clinical examination detects any such abnormalities. In the case of the patients presenting with sensory motor neuropathy, history of occupational exposure to n-hexane becomes important, as the sooner the disease is detected, the better the chances of recovery. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Antioxidant and antibacterial activities of acetonitrile and hexane extracts of Lentinus tigrinus and Pleurotus djamour

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This paper highlighted the antioxidant and antibacterial activities of Lentinus tigrinus and Pleurotus djamour. Extracts of mushroom fruiting bodies were obtained using hexane and acetonitrile solvents. Acetonitrile extracts of both mushrooms exhibited higher biological activities than hexane extrac...

Physicochemical characterisation of hexanic seed oil extract from ...

African Journals Online (AJOL)

The physicochemical characterisation of oil extracts from Schinus molle seeds collected in South Africa was performed. The oils were extracted in hexane, physicochemical parameters determined and lipids profiled by gas chromatography, in order to determine its potential for use in industry, ethnomedicine and its ...

evaluation of commercial FCC catalysts for hydrocarbon conversion. I. Physicochemical characterization and n-hexane conversion.

NARCIS (Netherlands)

Brait, A.; Brait, A.; Seshan, Kulathuiyer; Lercher, J.A.

1998-01-01

The physicochemical properties of six steam-stabilized, commercial FCC catalysts were compared in respect of their catalytic activity for n-hexane conversion. The conversion of n-hexane over these catalysts could be fully explained by three reaction pathways: protolytic cracking, protolytic

Proteomic analysis reveals resistance mechanism against biofuel hexane in Synechocystis sp. PCC 6803

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Liu Jie

2012-09-01

Full Text Available Abstract Background Recent studies have demonstrated that photosynthetic cyanobacteria could be an excellent cell factory to produce renewable biofuels and chemicals due to their capability to utilize solar energy and CO2 as the sole energy and carbon sources. Biosynthesis of carbon-neutral biofuel alkanes with good chemical and physical properties has been proposed. However, to make the process economically feasible, one major hurdle to improve the low cell tolerance to alkanes needed to be overcome. Results Towards the goal to develop robust and high-alkane-tolerant hosts, in this study, the responses of model cyanobacterial Synechocystis PCC 6803 to hexane, a representative of alkane, were investigated using a quantitative proteomics approach with iTRAQ - LC-MS/MS technologies. In total, 1,492 unique proteins were identified, representing about 42% of all predicted protein in the Synechocystis genome. Among all proteins identified, a total of 164 and 77 proteins were found up- and down-regulated, respectively. Functional annotation and KEGG pathway enrichment analyses showed that common stress responses were induced by hexane in Synechocystis. Notably, a large number of transporters and membrane-bound proteins, proteins against oxidative stress and proteins related to sulfur relay system and photosynthesis were induced, suggesting that they are possibly the major protection mechanisms against hexane toxicity. Conclusion The study provided the first comprehensive view of the complicated molecular mechanism employed by cyanobacterial model species, Synechocystis to defend against hexane stress. The study also provided a list of potential targets to engineer Synechocystis against hexane stress.

Phytochemical And Antidiarrhoeal Evaluation Of The Hexane And ...

African Journals Online (AJOL)

The hexane and methanol extracts of the leaves were screened for possible antidiarrhoeal activities on mice gastrointestinal tract using two models which include measure of inhibition of castor oil- induced diarrhoea and measure of intestinal transit time. The phytochemical analysis revealed the presence of carbohydrates, ...

Juglans regia Hexane Extract Exerts Antitumor Effect, Apoptosis ...

African Journals Online (AJOL)

Original Research Article. Juglans regia Hexane Extract Exerts Antitumor Effect,. Apoptosis Induction and Cell Circle Arrest in Prostate. Cancer Cells In vitro. Wei Li1, De-Yuan Li2*, ... composition of walnut is juglone (5-hydroxy-1, 4- naphthoquinone), the .... extract was confirmed by studying apoptotic body formation using ...

Phytochemical screening, cytotoxicity and antiviral activity of hexane fraction of Phaleria macrocarpa fruits

Science.gov (United States)

Ismaeel, Mahmud Yusef Yusef; Yaacob, Wan Ahmad; Tahir, Mariya Mohd.; Ibrahim, Nazlina

2015-09-01

Phaleria macrocarpa fruits have been widely used in the traditional medicine for the treatment of several infections. The current study was done to determine the phytochemical content, cytotoxicity and antiviral activity of the hexane fraction (HF) of P. macrocarpa fruits. In the hexane fraction of P. macarocarpa fruits, phytochemical screening showed the presence of terpenoids whereas saponins, alkaloids, tannins and anthraquinones were not present. Evaluation on Vero cell lines by using MTT assay showed that the 50% cytotoxic concentration (CC50) value was 0.48 mg/mL indicating that the fraction is not cytotoxic. Antiviral properties of the plant extracts were determined by plaque reduction assay. The effective concentration (EC50) was 0.18 mg/mL. Whereas the selective index (SI = CC50/EC50) of hexane fraction is 2.6 indicating low to moderate potential as antiviral agent.

Fractionation of commercial hexane and use of its fractions as extracting solvent of cottonseed oil

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Megahed, Ola A.

2001-04-01

Full Text Available The problem of producing off-graded cottonseed oil using locally produced commercial hexane as extracting solvent has explored this research. It was aimed in this work to investigate whether this problem can be solved by controlling the boiling range of the extracting solvent. Four different hexane fractions of different boiling ranges were prepared from commercial hexane. The boiling range of commercial hexane was 62-68ºC while the boiling ranges of the four fractions were 62- 64, 64-65, 65-66 and 66-68ºC. Commercial hexane and the prepared four hexane fractions were then used to extract cottonseed oil from a fixed seed sample. The five crude oil samples were then refined and bleached and their colours were measured. The results have shown that the heaviest hexane fraction ( b.r 66-68ºC produced the lightest coloured oils. The colour index of the bleached oil using this heavy cut was 190 compared to 350 using the original commercial hexane. However, the production of a commercial hexane cut having a narrow boiling range will be costly. Therefore, this research has been extended to investigate the suitability of a heavy petroleum cut which has a boiling range as wide as that of commercial hexane to extract cottonseed oil. The boiling range of this cut was 66-72ºC. The obtained results proved that the extraction of cottonseed oil using that heavy petroleum fraction produces much lighter oil than the use of conventional hexane solvent.En esta investigación se ha examinado el problema de producir aceite de semilla de algodón sin-clasificar usando hexano comercial producido localmente como disolvente. El objetivo de este trabajo fue investigar si este problema puede ser solucionado controlando el rango de ebullición del disolvente extractante. Cuatro fracciones diferentes de hexano de diversos rangos de ebullición fueron preparadas del hexano comercial. El rango al que ebullía el hexano comercial era 62-68ºC mientras que los

Chemical composition of the essential oil and hexanic fraction of Lippia and Lantana species

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Pâmela S. Silva

2010-11-01

Full Text Available A comparison between two extraction approaches of volatiles compounds from six species of Verbenaceae collected at Serra do Cipó, Minas Gerais, Brazil was done. The essential oil and hexanic fraction of leaves from two Lantana and four Lippia species collected in two different seasons were analyzed by GC/MS. Among various identified compounds from both extraction methods the majority of species showed major amounts of β-caryophyllene followed by germacrene D, bicyclogermacrene and α-pinene. Few differences were observed between the composition of essential oil and the hexanic fraction regarding the two studied genera. These results suggest that the analysis of hexanic fraction can be used, as an alternative way, to analyze the volatile compounds of the essential oil.

Isothermal (vapour + liquid) equilibrium data for binary systems of (n-hexane + CO2 or CHF3)

International Nuclear Information System (INIS)

Williams-Wynn, Mark D.; Naidoo, Paramespri; Ramjugernath, Deresh

2016-01-01

Highlights: • (Static-analytic + static-synthetic) phase equilibrium measurements. • Binary VLE data for (CO 2 + n-hexane) and (trifluoromethane + n-hexane). • Thermodynamic models were fitted to the experimental data. • Liquid–liquid immiscibility occurred with (trifluoromethane + n-hexane) system. - Abstract: The (vapour + liquid) equilibrium (VLE) was measured for the (carbon dioxide + n-hexane) binary system at temperatures between T = (303.1 and 323.1) K. In addition, VLE and (vapour + liquid + liquid) equilibria (VLLE) were determined for the (trifluoromethane + n-hexane) binary system at temperatures between T = (272.9 and 313.3) K and pressures in the range of P = (1.0 to 5.7) MPa. Measurements were undertaken in a static-analytic apparatus, with verification of experimental values undertaken using a static-synthetic equilibrium cell to measure bubble point pressures at several compositions. The phase equilibrium results were modelled with the Peng–Robinson equation of state with the Mathias–Copeman alpha function, coupled with the Wong–Sandler mixing rules. Regression of the data was performed with the NRTL and the UNIQUAC activity coefficient models with the Wong–Sandler mixing rules, and the performance of the models was compared. Critical loci for both systems were estimated, using the calculation procedures of Ungerer et al. and Heidemann and Khalil. For the (trifluoromethane + n-hexane) system, liquid–liquid immiscibility was experienced at the lowest temperature measured (T = 272.9 K). At higher temperatures, no immiscibility was visible during the measurements; however, the models continued to predict a miscibility gap.

Density and temperature effects on electron mobilities in gaseous, critical and liquid n-hexane, cyclohexane, and cyclopentane

International Nuclear Information System (INIS)

Huang, S.S.-S.; Freeman, G.R.

1978-01-01

In the low density vapors the density normalized mobilities μn of thermal electrons decreased in the order n-hexane > cyclopentane > cyclohexane. Mobilities in the critical fluids were 16 cm 2 /V s in n-hexane, 23 in cyclohexane, and 22 in cyclopentane. Mobilities in the liquids were independent of field up to the highest value used, which was 1.5 Td in the hexanes and 0.9 Td in cyclopentane. The mobilities and their temperature dependences were interpreted in terms of a model

Anti-venom potentials of Friedelin isolated from hexane extract ...

African Journals Online (AJOL)

... taenicidal, cough remedy, dysentery, cancer, diabetes mellitus, tuberculosis and snake bite remedy. In this report, an attempt has been made to evaluate the bioactive molecules in the plant that are anti-venom agents. Consequently, the stem bark was exhaustively extracted with hexane and subsequently with methanol.

Phase-Transfer Energetics of Small-Molecule Alcohols Across the Water-Hexane Interface: Molecular Dynamics Simulation Using Charge Equilibration Models

Science.gov (United States)

Bauer, Brad A.; Zhong, Yang; Meninger, David J.; Davis, Joseph E.; Patel, Sandeep

2010-01-01

We study the water-hexane interface using molecular dynamics (MD) and polarizable charge equilibration (CHEQ) force fields. Bulk densities for TIP4P-FQ water and hexane, 1.0086±0.0002 g/cm3 and 0.6378±0.0001 g/cm3, demonstrate excellent agreement with experiment. Interfacial width and interfacial tension are consistent with previously reported values. The in-plane component of the dielectric permittivity (ε∥) for water is shown to decrease from 81.7±0.04 to unity, transitioning longitudinally from bulk water to bulk hexane. ε∥ for hexane reaches a maximum in the interface, but this term represents only a small contribution to the total dielectric constant (as expected for a non-polar species). Structurally, net orientations of the molecules arise in the interfacial region such that hexane lies slightly parallel to the interface and water reorients to maximize hydrogen bonding. Interfacial potentials due to contributions of the water and hexane are calculated to be -567.9±0.13mV and 198.7±0.01mV, respectively, giving rise to a total potential in agreement with the range of values reported from previous simulations of similar systems. Potentials of mean force (PMF) calculated for methanol, ethanol, and 1-propanol for the transfer from water to hexane indicate an interfacial free energy minimum, corresponding to the amphiphilic nature of the molecules. The magnitudes of transfer free energies were further characterized from the solvation free energies of alcohols in water and hexane using thermodynamic integration. This analysis shows that solvation free energies for alcohols in hexane are 0.2-0.3 kcal/mol too unfavorable, whereas solvation of alcohols in water is approximately 1 kcal/mol too favorable. For the pure hexane-water interfacial simulations, we observe a monotonic decrease of the water dipole moment to near-vacuum values. This suggests that the electrostatic component of the desolvation free energy is not as severe for polarizable models than

Effect of hexane treatment and uniaxial stretching on bending ...

African Journals Online (AJOL)

PVDF) film was studied. The quantity, β31, defined as the bending piezoelectric stress constant, was calculated. After hexane treatment and uniaxial stretching of the PVDF film, the value of β31 was 5.75 mV/m and 8.00 mV/m for draw ratio of ...

Hydrogen bonds and van der Waals forces as tools for the construction of a herringbone pattern in the crystal structure of hexane-1,6-diaminium hexane-1,6-diyl bis(hydrogen phosphonate

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Guido J. Reiss

2017-01-01

Full Text Available The asymmetric unit of the title salt, [H3N(CH26NH3][(HOO2P(CH26PO2(OH], consists of one half of a hexane-1,6-diaminium dication and one half of a hexane-1,6-diyl bis(hydrogen phosphonate dianion. Both are located around different centres of inversion (Wyckoff sites: 2a and 2d of the space group P21/c. The shape of the hexane-1,6-diaminium cation is best described as a double hook. Both aminium groups as well as the two attached CH2 groups are turned out from the plane of the central four C atoms. In contrast, all six C atoms of the dianion are almost in a plane. The hydrogen phosphonate (–PO3H groups of the anions and the aminium groups of the cations form two-dimensional O—H... and O—H...N hydrogen-bonded networks parallel to the ac plane, built up from ten-membered and twelve-membered ring motifs with graph-set descriptors R33(10 and R54(12, respectively. These networks are linked by the alkylene chains of the anions and cations. The resulting three-dimensional network shows a herringbone pattern, which resembles the parent structures 1,6-diaminohexane and hexane-1,6-diphosphonic acid.

Comparison of Analgesic and Hypoglycemic Effect of Hexanic and Alcohlic Extract of Fenugreek Seed in Male Diabetic Rats

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Sima Nasri

2013-04-01

Full Text Available Background & Objectives: Diabetes mellitus is recognized with severe metabolic complications. Many herbal medicines have been recommended for treatment of diabetes. In this study, the antidiabetic and analgesic effect of hexanic and alcohlic extract Trigonella-foenum graecum was investigated in normal and streptozotocin-induced diabetic rats.  Methods: Present study was carried out in 2011 at Guilan University of Medical Sciences, 48 male Sprague Dawley rats (230-300 gr were divided into six groups: control, type 1 diabetic, and 4 treat ed groups that received intraperitonealy hexanic and alcoholic extract of fenugreek (100, 200 mg/kg body weight for 28 days. Two experimental models were used (acetic acid, and hot-plate tests in order to characterize the analgesic effect. Blood glucose was measured with glucometer. Data analyzed with spss software 16 and one way ANOVA and Tukey tests. P<0.05 was statistically significant.  Results: Compared to control rats, both of the aqueous - alcoholic and Hexan ic extract significantly reduced blood glucose level in all diabetics groups. This effect was stronger in groups that received Hexanic extract (p<0.05 . All groups received the aqueous - alcoholic and Hexan ic extract showed analgesic effect but this effect was more clear in the Hexanic 200 mg/kg group (p<0.05.  Conclusion: Fenugreek extract possesses hypoglycemic , and analgesic effects .

Hydropyrolysis of n-Hexane and Toluene to Acetylene in Rotating-Arc Plasma

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Jie Ma

2017-07-01

Full Text Available Thermal plasma pyrolysis is a powerful technology for converting waste or low-value materials to valuable gaseous hydrocarbons. This paper presents for the first time the hydropyrolysis of n-hexane and toluene in a rotating-arc plasma reactor. Effects of the mole ratio of H/C in the feed, power input and magnetic induction were investigated to evaluate the reaction performance. A lower H/C ratio could lead to a lower yield of C2H2 and lower specific energy consumption, and there existed an optimum range of power input for both n-hexane and toluene pyrolysis within the investigated range. The yield of C2H2 in n-hexane and toluene pyrolysis could reach 85% and 68%, respectively, with respective specific energy consumption (SEC of 13.8 kWh/kg·C2H2 and 19.9 kWh/kg·C2H2. Compared with the results reported in literature, the rotating-arc plasma process showed higher C2H2 yield and lower energy consumption, which is attributed to the better initial mixing of the reactant with the hot plasma gas and the more uniform temperature distribution.

Hydro-isomerization of n-hexane on bi-functional catalyst: Effect of total and hydrogen partial pressures

Science.gov (United States)

Thoa, Dao Thi Kim; Loc, Luu Cam

2017-09-01

The effect of both total pressure and hydrogen partial pressure during n-hexane hydro-isomerization over platinum impregnated on HZSM-5 was studied. n-Hexane hydro-isomerization was conducted at atmospheric pressure and 0.7 MPa to observe the influence of total pressure. In order to see the effect of hydrogen partial pressure, the reaction was taken place at different partial pressure of hydrogen varied from 307 hPa to 718 hPa by dilution with nitrogen to keep the total pressure at 0.1 MPa. Physico-chemical characteristics of catalyst were determined by the methods of nitrogen physi-sorption BET, SEM, XRD, TEM, NH3-TPD, TPR, and Hydrogen Pulse Chemi-sorption. Activity of catalyst in the hydro-isomerization of n-hexane was studied in a micro-flow reactor in the temperature range of 225-325 °C; the molar ratio H2/ hydrocarbon: 5.92, concentration of n-hexane: 9.2 mol.%, GHSV 2698 h-1. The obtained catalyst expressed high acid density, good reducing property, high metal dispersion, and good balance between metallic and acidic sites. It is excellent contact for n-hexane hydro-isomerization. At 250 °C, n-hexane conversion and selectivity were as high as 59-76 % and 85-99 %, respectively. It was found that catalytic activity was promoted either by total pressure or hydrogen partial pressure. At total pressure of 0.7 MPa while hydrogen partial pressure of 718 hPa, catalyst produced 63 RON liquid product containing friendly environmental iso-paraffins which is superior blending stock for green gasoline. Hydrogen did not only preserve catalyst actives by depressing hydrocracking and removing coke precursors but also facilitated hydride transfer step in the bi-functional bi-molecular mechanism.

icacy test of hexane extract of Annona squamosa L seeds for Chrysomya bezziana larvae growth in vitro

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April H Wardhana

2004-12-01

Full Text Available Chrysomya bezziana is primer agent causing myiasis in livestock and human throughout Africa to Asia. At present, treatment of myiasis using chemical synthetic insecticide causing environment and livestock production contaminations. The aim of this study was to evaluate the effect of hexane extract of Annona squamosa L seed to kill C. bezziana as botanical insecticide. Three level and method preparation of larvae (L1, L2 and L3 were carried out. Meat blood mixture (MBM and larval rearing media (LRM were mixed with hexane extract of A. squamosa L seed and tested to 625 and 750 larvae (L1and L2 respectively, while for L3 625 larvae were soaked in the solution containing the hexane extract. This last preparation was carried out to observe the effect of toxic contact. Each larvae treatment was divided into 5 levels such as negative control using distillation water (PO, given 0.25% hexane extract (P I; 0.50% (P II; 0.75% (P III and positive control was given with 0.10% Asuntol®. This assay was to know digest toxic effect of hexane extract of A. squamosa L seed for those larvae. Number of 625 instar III larvae (L3 was soaked in the solution containing the hexane extract of A. squamosa L seed for 10 second, placed into vermicullite and incubated on 36oC. This assay was to know contact toxic effect of them. All of larvae were allowed to become pupae. Parameters oberserve were number of larvae death, pupae weight and number of pupae become into fly. The data was analyzed using Anova (5% and Z test (5% then smallest significant difference test (BNT 5%. The results showed that 0.50% of hexane extract of A. squamosa L seed was able to decrease pupae weight for L1 and L2 and to cause fail pupae become fly (P0.05.

Gastro-protective effect of crude hexane leaf extract of Sesamum ...

African Journals Online (AJOL)

The gastroprotective effect of the hexane extract of the leaves of Sesamum indicum (HESI) was investigated in twenty-eight male rabbits. Gastroprotective activity against necrotizing agent induced ulceration was studied. Gastric wall mucus was determined by standard methods. Anti-secretory activity was determined in ...

Infrared reflection absorption spectroscopy study of radiation-heterogeneous processes in the system of aluminum-hexane

International Nuclear Information System (INIS)

Gadzhieva, N.N.; Rimikhanova, A.N.; Garibov, A.A.

2004-01-01

Full text: Infrared reflection absorption spectroscopy (IRRAS) was applied to study the regularities of radiation conversion of hexane on the surface of aluminum. The research object was the thin polished aluminum plate by mark of AD-00 with reflection coefficient R=0.8†0.85 in infrared range λ=2.2†15 μ . As adsorbate unsaturated vapors of spectroscopy clear hexane were used. The absorption of hexane (C 2 H 14 ) was being studied manometric at pressures P=(0.1†1.0)·10 2 Pa , what corresponded to monolayer value of 1-10. The samples were irradiated with γ-quanta of 60 Co with D=1.03 Gy·s -1 doze rate. Infrared reflection spectrum when linear-polarized radiation fall on the sample under angle ψ=10 o was measured by spectrophotometer 'Specord 71 JR' in diapason of 4000-650cm -1 at the temperature by mean of special reflecting arrangements. Formation of molecular hydrogen (H 2 ) and other gaseous products of decomposition were controlled by chromotographical and infrared spectroscopical methods. The analysis of hexane infrared absorption spectra after radiation-stimulated adsorption on the surface of aluminum, points out the formation of H-bonded hydrocarbon complex ( ν∼2680cm -1 ) with much loosening of C-H bond (the molecular form of absorption) and the possibility of proceeding dissociative absorption with formation of metal-alkyls (ν∼2880, 2920, 2970 cm -1 ). Probability of the last mentioned process, which proceeds in the most defective centers, increases with increasing of γ-radiation doze. It was established that the radiation processes in hetero system Al-ads.C 6 H 14 accelerate the radiolysis of hexane. At all these the radiation decomposition of hexane in hetero system Al-ads.C 6 H 14 is accompanied by formation the surface hydrides (ν∼1700-2000 cm -1 ), acetylene (ν∼3200-3300 cm -1 ), ethylene (ν∼980 cm -1 ), and also gaseous products of molecular hydrogen decomposition (H 2 ) and hydrocarbons C 1 -C 5 (bands with maxima 770, 790

Acquired Color Vision Defects and Hexane Exposure: A Study of San Francisco Bay Area Automotive Mechanics.

Science.gov (United States)

Beckman, Stella; Eisen, Ellen A; Bates, Michael N; Liu, Sa; Haegerstrom-Portnoy, Gunilla; Hammond, S Katharine

2016-06-01

Occupational exposure to solvents, including n-hexane, has been associated with acquired color vision defects. Blue-yellow defects are most common and may be due to neurotoxicity or retinal damage. Acetone may potentiate the neurotoxicity of n-hexane. We present results on nonhexane solvent and hexane exposure and color vision from a cross-sectional study of 835 automotive repair workers in the San Francisco Bay Area, California (2007-2013). Cumulative exposure was estimated from self-reported work history, and color vision was assessed using the Lanthony desaturated D-15 panel test. Log-binomial regression was used to estimate prevalence ratios for color vision defects. Acquired color vision defects were present in 29% of participants, of which 70% were blue-yellow. Elevated prevalence ratios were found for nonhexane solvent exposure, with a maximum of 1.31 (95% confidence interval (CI): 0.86, 2.00) for blue-yellow. Among participants aged ≤50 years, the prevalence ratio for blue-yellow defects was 2.17 (95% CI: 1.03, 4.56) in the highest quartile of nonhexane solvent exposure and 1.62 (95% CI: 0.97, 2.72) in the highest category of exposure to hexane with acetone coexposure. Cumulative exposures to hexane and nonhexane solvents in the highest exposure categories were associated with elevated prevalence ratios for color vision defects in younger participants. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Antimicrobial activities of essential oil and hexane extract of Florence fennel [Foeniculum vulgare var. azoricum (Mill.) Thell.] against foodborne microorganisms.

Science.gov (United States)

Cetin, Bülent; Ozer, Hakan; Cakir, Ahmet; Polat, Taşkin; Dursun, Atilla; Mete, Ebru; Oztürk, Erdoğan; Ekinci, Melek

2010-02-01

The objective of this study was to determine the chemical compositions of the essential oil and hexane extract isolated from the inflorescence, leaf stems, and aerial parts of Florence fennel and the antimicrobial activities of the essential oil, hexane extract, and their major component, anethole, against a large variety of foodborne microorganisms. Gas chromatography and gas chromatography-mass spectrometry analysis showed that the essential oils obtained from inflorescence, leaf stems, and whole aerial parts contained (E)-anethole (59.28-71.69%), limonene (8.30-10.73%), apiole (trace to 9.23%), beta-fenchyl acetate (3.02-4.80%), and perillene (2.16-3.29%) as the main components. Likewise, the hexane extract of the plant sample exhibited a similar chemical composition, and it contained (E)-anethole (53.00%), limonene (27.16%), gamma-terpinene (4.09%), and perillene (3.78%). However, the hexane extract also contained less volatile components such as n-hexadecanoic acid (1.62%), methyl palmitate (1.17%), and linoleic acid (1.15%). The in vitro antimicrobial assays showed that the essential oil, anethole, and hexane extract were effective against most of the foodborne pathogenic, saprophytic, probiotic, and mycotoxigenic microorganisms tested. The results of the present study revealed that (E)-anethole, the main component of Florence fennel essential oil, is responsible for the antimicrobial activity and that the essential oils as well as the hexane extract can be used as a food preservative. This study is the first report showing the antimicrobial activities of essential oil and hexane extract of Florence fennel against probiotic bacteria.

Effect of methanol, n-hexane and aqueous extract of Irvingia ...

African Journals Online (AJOL)

Bush mango leaf (Irvingia gabonensis) is commonly used locally to treat diarrhoea. The present study evaluated the anti-diarrhoea effect of this plant extract on albino rats induced with castor oil. Fresh tender leaf of this plant was collected, air-dried, powdered and percolated in n-hexane, methanol and aqueous solvents.

Oil extraction from olive foot cake with acidic hexane

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Kmieciak, S.

1991-02-01

Full Text Available The use of acidic hexane as a solvent increases the extracted oil yield from olive foot cake. Two extraction procedures are studied: open air extraction at room temperature and Soxhlet exhaustive extraction. The additional yield is about 5% for a 2.5% acetic acid content in case of open air extraction and turns out to be 9% for 7.5% acetic acid content in the Soxhlet procedure. An analysis of the extracted oil shows a light increase of the acidity of oil. The improved yield may be attributed to the action of acetic acid on the decomposition of intercellular structures and binding of some polar lipids. The phospholipids content of oil extracted with 7.5% acidic hexane is found to be 25 times more than with pure hexane.

El uso de hexano ácido como disolvente aumenta el rendimiento de aceite extraído de orujo de aceituna. Se han estudiado dos procedimientos de extracción: extracción al aire libre a temperatura ambiente y extracción exhaustiva en Soxhlet. En el caso de extracción al aire libre el rendimiento adicional es alrededor del 5% para un contenido del 2'5% en ácido acético y llega a ser en el procedimiento en Soxhlet del 9% para un contenido en ácido acético del 7'5%. Un análisis del aceite extraído mostró un ligero aumento de la acidez del aceite. La mejora del rendimiento puede ser atribuida a la acción del ácido acético sobre la descomposición de estructuras intercelulares y uniones de lípidos polares. Se ha encontrado que el contenido en fosfolípidos del aceite extraído con el 7*5% de hexano ácido es 25 veces mayor que con hexano puro.

Inhalation reproductive toxicology studies: Male dominant lethal study of n-hexane in Swiss (CD-1) mice: Final report

Energy Technology Data Exchange (ETDEWEB)

Mast, T.J.; Rommereim, R.L.; Evanoff, J.J.; Sasser, L.B.; Decker, J.R.; Stoney, K.H.; Weigel, R.J.; Westerberg, R.B.

1988-08-01

The straight-chain hydrocarbon, n-hexane, is a volatile, ubiquitous solvent routinely used in industrial environments; consequently, the opportunity for industrial, environmental or accidental exposure to hexane vapors is significant. Although myelinated nerve tissue is the primary target organ of hexane, the testes have also been identified as being sensitive to hexacarbon exposure. The objective of this study was to evaluate male dominant lethal effects in Swiss (CD-1) mice after exposure to 0, 200, 1000, or 5000 ppM n-hexane, 20 h/day for 5 consecutive days. Each exposure concentration consisted of 30 randomly selected, proven male breeders; 4 groups. The mice were weighed just prior to the first day of exposure and at weekly intervals until sacrifice. Ten males in each dose group were sacrificed one day after the cessation of exposure, and their testes and epididymides were removed for evaluation of the germinal epithelium. The remaining male mice, 20 per group, were individually housed in hanging wire-mesh breeding cages where they were mated with unexposed, virgin females for eight weekly intervals; new females were provided each week. The mated females were sacrificed 12 days after the last day of cohabitation and their reproductive status and the number and viability of the implants were recorded. The appearance and behavior of the male mice were unremarkable throughout the study period and no evidence of n-hexane toxicity was observed. 18 refs., 3 figs., 11 tabs.

Inhalation reproductive toxicology studies: Male dominant lethal study of n-hexane in Swiss (CD-1) mice: Final report

International Nuclear Information System (INIS)

Mast, T.J.; Rommereim, R.L.; Evanoff, J.J.; Sasser, L.B.; Decker, J.R.; Stoney, K.H.; Weigel, R.J.; Westerberg, R.B.

1988-08-01

The straight-chain hydrocarbon, n-hexane, is a volatile, ubiquitous solvent routinely used in industrial environments; consequently, the opportunity for industrial, environmental or accidental exposure to hexane vapors is significant. Although myelinated nerve tissue is the primary target organ of hexane, the testes have also been identified as being sensitive to hexacarbon exposure. The objective of this study was to evaluate male dominant lethal effects in Swiss (CD-1) mice after exposure to 0, 200, 1000, or 5000 ppM n-hexane, 20 h/day for 5 consecutive days. Each exposure concentration consisted of 30 randomly selected, proven male breeders; 4 groups. The mice were weighed just prior to the first day of exposure and at weekly intervals until sacrifice. Ten males in each dose group were sacrificed one day after the cessation of exposure, and their testes and epididymides were removed for evaluation of the germinal epithelium. The remaining male mice, 20 per group, were individually housed in hanging wire-mesh breeding cages where they were mated with unexposed, virgin females for eight weekly intervals; new females were provided each week. The mated females were sacrificed 12 days after the last day of cohabitation and their reproductive status and the number and viability of the implants were recorded. The appearance and behavior of the male mice were unremarkable throughout the study period and no evidence of n-hexane toxicity was observed. 18 refs., 3 figs., 11 tabs

Comparison of antibacterial activity of Talok (Muntingia calabura L) leaves ethanolic and n-hexane extracts on Propionibacterium acnes

Science.gov (United States)

Desrini, Sufi; Ghiffary, Hifzhan Maulana

2018-04-01

Muntingia calabura L., also known locally as Talok or Kersen, is a plant which has been widely used as traditional medicine in Indonesia. In this study, we evaluated the antibacterial activity of Muntingia calabura L. Leaves ethanolic and n-hexane extract extract on Propionibacterium acnes. Antibacterial activity was determined in the extracts using agar well diffusion method. The antibacterial activities of each extract (2 mg/mL, 8 mg/ml, 20 mg/mL 30 mg/mL, and 40 mg/mL) were tested against to Propionibacterium acnes. Zone of inhibition of ethanolic extract and n-hexane extract was measured, compared, and analyzed by using a statistical programme. The phytochemical analyses of the plants were carried out using thin chromatography layer (TLC). The average diameter zone of inhibition at the concentration of 2 mg/mL of the ethanolic extract is 9,97 mm while n-Hexane extract at the same concentration showed 0 mm. Statistical test used was non-parametric test using Kruskal Wallis test which was continued to the Mann-Whitney to see the magnitude of the difference between concentration among groups. Kruskal-Wallis test revealed a significant value 0,000. Based on the result of Post Hoc test using Mann - Whitney test, there is the statistically significant difference between each concentration of ethanolic extract and n-hexane as well as positive control group (p-value < 0,05). Both extracts have antibacterial activity on P.acne. However, ethanolic extract of Muntingia calabura L. is better in inhibiting Propionibacterium acnes growth than n-hexane extract.

High Pressure Vapor-Liquid Equilibrium of Supercritical Carbon Dioxide + n-Hexane System

Institute of Scientific and Technical Information of China (English)

YU Jinglin; TIAN Yiling; ZHU Rongjiao; LIU Zhihua

2006-01-01

Vapor-liquid equilibrium data of supercritical carbon dioxide + n-hexane system were measured at 313.15 K,333.15 K,353.15 K,and 373.15 K and their molar volumes and densities were measured both in the subcritical and supercritical regions ranging from 2.15 to 12.63 MPa using a variable-volume autoclave.The thermodynamic properties including mole fractions,densities,and molar volumes of the system were calculated with an equation of state by Heilig and Franck,in which a repulsion term and a square-well potential attraction term for intermolecular interaction was used.The pairwise combination rule was used to calculate the square-well molecular interaction potential and three adjustable parameters (ω,kε,kσ) were obtained.The Heilig-Franck equation of state is found to have good correlation with binary vapor-liquid equilibrium data of the carbon dioxide + n-hexane system.

Supercritical SC-CO2 and Soxhlet n-Hexane Extract of Tunisian Opuntia ficus indica Seeds and Fatty Acids Analysis

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Nizar Yeddes

2012-01-01

Full Text Available The fatty acids profiles of Tunisian Opuntia ficus indica seeds (spiny and thornless form were investigated. Results of supercritical carbon dioxide (SC-CO2 and soxhlet n-hexane extract were compared. Quantitatively, the better yield was obtained through soxhlet n-hexane: 10.32% (spiny and 8.91% (thornless against 3.4% (spiny and 1.94% (thornless by SC-CO2 extract (T = 40°C, P=180 bar, time = 135 mn, CO2 flow rate = 15 mL·s−1. Qualitatively, the main fatty acids components were the same for the two types of extraction. Linoleic acid was the major compound, SC-CO2: 57.60% (spiny, 59.98% (thornless, soxhlet n-hexane: 57.54% (spiny, 60.66% (thornless, followed by oleic acid, SC-CO2: 22.31% (spiny, 22.40% (thornless, soxhlet n-hexane: 25.28% (spiny, 20.58% (thornless and palmitic acid, SC-CO2: 14.3% (spiny, 12.92% (thornless, soxhlet n-hexane: 11.33% (spiny, 13.08% (thornless. The SC-CO2 profiles fatty acids showed a richness with other minority compounds such as C20:1, C20:2, and C22.The seeds oil was highly unsaturated (US = 4.44–5.25, and the rising temperatures donot affect the selectivity of fatty acids extract by SC-CO2: US = 4.44 (T = 40°C and 4.13 (T = 70°C.

Supercritical SC-CO2 and Soxhlet n-Hexane Extract of Tunisian Opuntia ficus indica Seeds and Fatty Acids Analysis

Science.gov (United States)

Yeddes, Nizar; Chérif, Jamila Kalthoum; Jrad, Amel; Barth, Danielle; Trabelsi-Ayadi, Malika

2012-01-01

The fatty acids profiles of Tunisian Opuntia ficus indica seeds (spiny and thornless form) were investigated. Results of supercritical carbon dioxide (SC-CO2) and soxhlet n-hexane extract were compared. Quantitatively, the better yield was obtained through soxhlet n-hexane: 10.32% (spiny) and 8.91% (thornless) against 3.4% (spiny) and 1.94% (thornless) by SC-CO2 extract (T = 40°C, P = 180 bar, time = 135 mn, CO2 flow rate = 15 mL·s−1). Qualitatively, the main fatty acids components were the same for the two types of extraction. Linoleic acid was the major compound, SC-CO2: 57.60% (spiny), 59.98% (thornless), soxhlet n-hexane: 57.54% (spiny), 60.66% (thornless), followed by oleic acid, SC-CO2: 22.31% (spiny), 22.40% (thornless), soxhlet n-hexane: 25.28% (spiny), 20.58% (thornless) and palmitic acid, SC-CO2: 14.3% (spiny), 12.92% (thornless), soxhlet n-hexane: 11.33% (spiny), 13.08% (thornless). The SC-CO2 profiles fatty acids showed a richness with other minority compounds such as C20:1, C20:2, and C22.The seeds oil was highly unsaturated (US = 4.44–5.25), and the rising temperatures donot affect the selectivity of fatty acids extract by SC-CO2: US = 4.44 (T = 40°C) and 4.13 (T = 70°C). PMID:22754699

Supercritical SC-CO(2) and Soxhlet n-Hexane Extract of Tunisian Opuntia ficus indica Seeds and Fatty Acids Analysis.

Science.gov (United States)

Yeddes, Nizar; Chérif, Jamila Kalthoum; Jrad, Amel; Barth, Danielle; Trabelsi-Ayadi, Malika

2012-01-01

The fatty acids profiles of Tunisian Opuntia ficus indica seeds (spiny and thornless form) were investigated. Results of supercritical carbon dioxide (SC-CO(2)) and soxhlet n-hexane extract were compared. Quantitatively, the better yield was obtained through soxhlet n-hexane: 10.32% (spiny) and 8.91% (thornless) against 3.4% (spiny) and 1.94% (thornless) by SC-CO(2) extract (T = 40°C, P = 180 bar, time = 135 mn, CO(2) flow rate = 15 mL·s(-1)). Qualitatively, the main fatty acids components were the same for the two types of extraction. Linoleic acid was the major compound, SC-CO(2): 57.60% (spiny), 59.98% (thornless), soxhlet n-hexane: 57.54% (spiny), 60.66% (thornless), followed by oleic acid, SC-CO(2): 22.31% (spiny), 22.40% (thornless), soxhlet n-hexane: 25.28% (spiny), 20.58% (thornless) and palmitic acid, SC-CO(2): 14.3% (spiny), 12.92% (thornless), soxhlet n-hexane: 11.33% (spiny), 13.08% (thornless). The SC-CO(2) profiles fatty acids showed a richness with other minority compounds such as C(20:1), C(20:2), and C(22).The seeds oil was highly unsaturated (US = 4.44-5.25), and the rising temperatures donot affect the selectivity of fatty acids extract by SC-CO2: US = 4.44 (T = 40°C) and 4.13 (T = 70°C).

Normalized fluctuations, H2O vs n-hexane: Site-correlated percolation

Science.gov (United States)

Koga, Yoshikata; Westh, Peter; Sawamura, Seiji; Taniguchi, Yoshihiro

1996-08-01

Entropy, volume and the cross fluctuations were normalized to the average volume of a coarse grain with a fixed number of molecules, within which the local and instantaneous value of interest is evaluated. Comparisons were made between liquid H2O and n-hexane in the range from -10 °C to 120 °C and from 0.1 MPa to 500 MPa. The difference between H2O and n-hexane in temperature and pressure dependencies of these normalized fluctuations was explained in terms of the site-correlated percolation theory for H2O. In particular, the temperature increase was confirmed to reduce the hydrogen bond probability, while the pressure appeared to have little effect on the hydrogen bond probability. According to the Le Chatelier principle, however, the putative formation of ``ice-like'' patches at low temperatures due to the site-correlated percolation requirement is retarded by pressure increases. Thus, only in the limited region of low pressure (<300 MPa) and temperature (<60 °C), the fluctuating ice-like patches are considered to persist.

Comparison of Hexane Vapour Permeation in Two Different Polymeric Membranes via an Innovative In-line FID Detection Method

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Z. Petrusová

2017-07-01

Full Text Available This manuscript presents a novel method for the analysis of vapour permeation through polymeric membranes based on in-line analysis of the permeate with an FID detector. The hexane vapour permeation was studied for two commercially available membranes, namely low-density polyethylene (LDPE and thin-film-composite polyamide (PA membrane. The hexane permeation was studied at temperatures of 25–45 °C, hexane vapour activity in the range of 0.2–0.8 and trans-membrane pressures of 5–50 kPa. Two fundamentally different membranes were chosen to demonstrate the potential and sensitivity of the permeation apparatus. Upon increasing the temperature from 25 to 45 °C, the flux in LDPE was found to increase almost fourfold over the whole activity range. The nonlinear increase of the flux with activity indicates plasticization of the polymer by hexane. Contrarily, the flux in the PA membrane increases almost linearly with activity, with only a minor upward curvature. Since the PA is far away from any phase transition, it is less temperature-dependent than LDPE. The activation energy for permeation demonstrates that the temperature dependence in the LDPE membrane is dominated by changes in diffusion, whereas it is dominated by changes in solubility in the PA membrane.

Radiation- stimulated adsorption of n-hexane on the surface of silicon

International Nuclear Information System (INIS)

Hajiyeva, N.N.

2014-01-01

Full text : This paper presents the results of studies of radiation-stimulated adsorption of n-hexane on a silicon surface, obtained by infrared reflection-absorption spectroscopy method. It has been used a monocrystal silicon plate with high reflectance coefficient of the surface. Irradiation of the samples was carried out on gamma-quantum source of 60Co

Inhalation developmental toxicology studies: Teratology study of n-hexane in mice: Final report

Energy Technology Data Exchange (ETDEWEB)

Mast, T.J.; Decker, J.R.; Stoney, K.H.; Westerberg, R.B.; Evanoff, J.J.; Rommereim, R.L.; Weigel, R.J.

1988-05-01

Gestational exposure to n-hexane resulted in an increase in the number of resorbed fetuses for exposure groups relative to the control group; however, the increases were not directly correlated to exposure concentration. The differences were statistically significant for the 200-ppM with respect to total intrauterine death (early plus late resorptions), and with respect to late resorptions for the 5000-ppM group. A small, but statistically significant, reduction in female (but not male) fetal body weight relative to the control group was observed at the 5000-ppM exposure level. There were no exposure-related increases in any individual fetal malformation or variation, nor was there any increase in the incidence of combined malformations or variations. Gestational exposure of CD-1 mice to n-hexane vapors appeared to cause a degree of concentration-related developmental toxicity in the absence of overt maternal toxicity, but the test material was not found to be teratogenic. This developmental toxicity was manifested as an increase in the number of resorptions per litter for all exposure levels, and as a decrease in the uterine: extra-gestational weight gain ratio at the 5000-ppM exposure level. Because of the significant increase in the number of resorptions at the 200-ppM exposure level, a no observable effect level (NOEL) for developmental toxicity was not established for exposure of mice to 200, 1000 or 5000-ppM n-hexane vapors. 21 refs., 3 figs., 9 tabs.

Analysis of petroleum contaminated soils by spectral modeling and pure response profile recovery of n-hexane

International Nuclear Information System (INIS)

Chakraborty, Somsubhra; Weindorf, David C.; Li, Bin; Ali, Md. Nasim; Majumdar, K.; Ray, D.P.

2014-01-01

This pilot study compared penalized spline regression (PSR) and random forest (RF) regression using visible and near-infrared diffuse reflectance spectroscopy (VisNIR DRS) derived spectra of 164 petroleum contaminated soils after two different spectral pretreatments [first derivative (FD) and standard normal variate (SNV) followed by detrending] for rapid quantification of soil petroleum contamination. Additionally, a new analytical approach was proposed for the recovery of the pure spectral and concentration profiles of n-hexane present in the unresolved mixture of petroleum contaminated soils using multivariate curve resolution alternating least squares (MCR-ALS). The PSR model using FD spectra (r 2  = 0.87, RMSE = 0.580 log 10  mg kg −1 , and residual prediction deviation = 2.78) outperformed all other models tested. Quantitative results obtained by MCR-ALS for n-hexane in presence of interferences (r 2  = 0.65 and RMSE 0.261 log 10  mg kg −1 ) were comparable to those obtained using FD (PSR) model. Furthermore, MCR ALS was able to recover pure spectra of n-hexane. - Highlights: • We predicted soil petroleum contamination with VisNIR DRS spectra. • We examined 2 spectral pretreatments and 2 multivariate models. • MCR-ALS was used for compositional and spectral resolution of n-hexane. • Penalized spline regression performed best for quantifying soil TPH. • MCR-ALS was promising for resolution of complex soil–petroleum mixture. - Use of VisNIR DRS for rapid quantification of soil TPH and resolution of complex soil petroleum mixtures

Activity of the main fatty acid components of the hexane leaf extract ...

African Journals Online (AJOL)

The composition of hexane leaf extract of Ricinus communis was determined by gas chromatography– mass spectrometry (GC-MS) to contain four fatty acids: linolenic acid (47.76%), linoleic acid (15.28%), palmitic acid (13.01%), and stearic acid (1.73%). The insectistatic and insecticidal activities of the two major ...

Effect of Pressure on Absorption Spectra of Lycopene in n-Hexane and CS2 Solvents

Science.gov (United States)

Zhang, Wei; Liu, Wei-Long; Zheng, Zhi-Ren; Huo, Ming-Ming; Li, Ai-Hua; Yang, Bin

2010-01-01

The absorption spectra of lycopene in n-hexane and CS2 are measured under high pressure and the results are compared with β-carotene. In the lower pressure range, the deviation from the linear dependence on the Bayliss parameter (BP) for β-carotene is more visible than that for lycopene. With the further increase of the solvent BP, the 0-0 bands of lycopene and β-carotene red shift at almost the same rate in n-hexane; however, the 0-0 band of lycopene red shifts slower than that of β-carotene in CS2. The origins of these diversities are discussed taking into account the dispersion interactions and structures of solute and solvent molecules.

Synthesis of Conformationally North-Locked Pyrimidine Nucleosides Built on an Oxabicyclo[3.1.0]hexane Scaffold | Center for Cancer Research

Science.gov (United States)

Beginning with a known 3-oxabicyclo[3.1.0]-hexane scaffold, the relocation of the fused cyclopropane ring bond and the shifting of the oxygen atom to an alternative location engendered a new 2-oxabicyclo[3.1.0]hexane template that mimics more closely the tetrahydrofuran ring of conventional nucleosides. The synthesis of this new class of locked nucleosides involved a novel

The study of the radiation chemical transformation of the hexane on the surface of aluminium by IR-spectroscopy method

International Nuclear Information System (INIS)

Rimikhanova, A.N.

2006-01-01

Full text: In this work the experimental results of the radiation-chemical transformation of hexane on the aluminum surface obtained by IR spectroscopy method at room temperature have been presented. The metallic aluminum plates which was obtained by stage pressing granules by mark of AD-00 with the reflection coefficient R=0,85 in the middle infrared range of waves length λ=15 ± 2,2 mkm were used. As an adsorbate unsaturated vapors of hexane were used, the absorption of which was being carried out at the room temperature by the method. The radiation of system was carried out with γ-quanta of Co 60 with doze rate of 1,03 Gy/s - 1, and the absorbed doze in the system was (0,5-2)10 4 Gy. IR reflection spectra when beams fall on the sample under angle near the slipping were measured in diapason of 3600-650 cm - 1 by the spectrophotometer S pecord 71IR . The radiation chemical decomposition of hexane in heterosystem was being traced in stretching (3000-2700 cm - 1) and deformation (1500-1300 cm - 1) vibration diapasons of C-H bonds. The analysis of IR reflection spectra of Al-ads.hexane heterosystem showed that the main products of radiation chemical transformation are hydrocarbons C1-C5, olefins: propylene, butene-1, hexene-1, transhexene-3 and hydrocarbons more heavy than hexane. In frequency range of 1700-2000 cm - 1 the absorption bands of Al-H vibration which concern to aluminum hydrides are founded. By increasing of radiation dose the tendency of increasing of hydrogen accumulation as aluminum hydrides has been established

Stability of carotenoids toward UV-irradiation in hexane solution

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DRAGAN CVETKOVIC

2008-01-01

Full Text Available The stabilities of four selected carotenoids dissolved in hexane, two carotenes and two xanthophylls, toward UV-irradiation of three different ranges (UV-A, UV-B and UV-C were studied in this work. The carotenoids underwent bleaching via a probable free radical mediated mechanism following first-order kinetics. The bleaching rates were highly dependent on the input of the involved photons and, although not consistently, on the chemical structures of the investigated compounds. For the two xanthophylls, a possible role of oxygen associated with their bleaching cannot be neglected.

HEXAN - a hexagonal nodal code for solving the diffusion equation

International Nuclear Information System (INIS)

Makai, M.

1982-07-01

This report describes the theory of and provides a user's manual for the HEXAN program, which is a nodal program for the solution of the few-group diffusion equation in hexagonal geometry. Based upon symmetry considerations, the theory provides an analytical solution in a homogeneous node. WWER and HTGR test problem solutions are presented. The equivalence of the finite-difference scheme and the response matrix method is proven. The properties of a symmetric node's response matrix are investigated. (author)

Effect of Pressure on Absorption Spectra of Lycopene in n-Hexane and CS2 Solvents

International Nuclear Information System (INIS)

Wei, Zhang; Wei-Long, Liu; Zhi-Ren, Zheng; Ming-Ming, Huo; Ai-Hua, Li; Bin, Yang

2010-01-01

The absorption spectra of lycopene in n-hexane and CS 2 are measured under high pressure and the results are compared with β-carotene. In the lower pressure range, the deviation from the linear dependence on the Bayliss parameter (BP) for β-carotene is more visible than that for lycopene. With the further increase of the solvent BP, the 0–0 bands of lycopene and β-carotene red shift at almost the same rate in n-hexane; however, the 0–0 band of lycopene red shifts slower than that of β-carotene in CS 2 . The origins of these diversities are discussed taking into account the dispersion interactions and structures of solute and solvent molecules. (atomic and molecular physics)

Urinary 2,5-hexanedione in workers exposed to n-hexane: influence of the sample treatment

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Daniela Magalhães Nolasco

2007-08-01

Full Text Available The aim of the present study was to determine 2,5-hexanedione (2,5-HD, a metabolite of n-hexane, by gas chromatography/flame ionization detection in 31 workers exposed to n-hexane after two types of sample pretreatment, i.e., with (total 2,5-HD and without (free 2,5-HD acid hydrolysis. The mean urinary 2,5-HD was 0.52 mg/L (free and 2.88 mg/L (total, this difference being significant (Student t-test, p < 0.05. The differences in the results according to the sample treatment support the need to modify the current Brazilian legislation, which proposes the analysis of 2,5-HD without indicating whether it is the free or total metabolite.

A Mesopore-Dependent Catalytic Cracking of n-Hexane Over Mesoporous Nanostructured ZSM-5.

Science.gov (United States)

Qamar, M; Ahmed, M I; Qamaruddin, M; Asif, M; Sanhoob, M; Muraza, O; Khan, M Y

2018-08-01

Herein, pore size, crystalinity, and Si/Al ratio of mesoporous ZSM-5 (MFI) nanocrystals was controlled by synthesis parameters, such as surfactant concentration ([3-(trimethoxysilyl)propyl] hexa-decyl dimethyl ammonium chloride), sodium hydroxide concentrations, synthesis temperature and time. The morphology, surface structure and composition of the MFI particles was systematically investigated. More notably, the mesopore-dependent catalytic activity of ZSM-5 was evaluated by studying the cracking of n-hexane. The findings suggest the porosity has pronounced impact on the catalytic activity, selectivity and stability of ZSM-5 nanocrystals. Critical surface attributes such as nature of acid sites (Brønsted and Lewis), concentration, and strength are obtained by the infrared study of adsorbed probe molecules (pyridine) and the temperature programmed desorption. In spite of being weaker in Si/Al ratio or acidic strength, mesoporous catalysts showed more stable and efficient cracking of n-hexane suggesting that acidity seems not the predominant factor operative in the activity, selectivity and stability.

Impact of structural modification of 1,2,4-thiadiazole derivatives on thermodynamics of solubility and solvation processes in 1-octanol and n-hexane

International Nuclear Information System (INIS)

Surov, Artem O.; Bui, Cong Trinh; Volkova, Tatyana V.; Proshin, Alexey N.; Perlovich, German L.

2016-01-01

Highlights: • Solubility processes of some 1,2,4-thiadiazoles in n-hexane and 1-octanol were investigated. • Solvation processes of some 1,2,4-thiadiazoles in n-hexane and 1-octanol were studied. • Transfer processes from n-hexane to 1-octanol were evaluated. • Impact of various substituents in 1,2,4-thiadiazoles on the mentioned processes was studied. - Abstract: Influence of a structural modification on thermodynamic aspects of solubility and solvation processes of the 1,2,4-thiadiazole drug-like compounds in pharmaceutically relevant solvents n-hexane and 1-octanol was investigated. The solubility of the compounds in 1-octanol does not substantially depend on the nature and position of the substituent in the phenyl moiety. In n-hexane, however, the introduction of any substituent in the phenyl ring of the 1,2,4-thiadiazole molecule reduces the solubility in the solvent. In order to rationalize the relationships between the structure of 1,2,4-thiadiazoles and their solubility, the latter was considered in terms of two fundamental processes: sublimation and solvation. It was found that for the most of the compounds the solubility change in both solvents is a consequence of competition between the sublimation and solvation contributions, i.e. the introduction of substituents leads to growth of the sublimation Gibbs energy and increase in the solvation Gibbs energy. Thermodynamic parameters of the transfer process of the compounds from n-hexane to 1-octanol, which is a model of the blood–brain barrier (BBB), were also analyzed.

Molecular dynamics studies of the melting of butane and hexane monolayers adsorbed on the basal-plane surface of graphite

DEFF Research Database (Denmark)

Hansen, Flemming Yssing; Newton, J. C.; Taub, H.

1993-01-01

The effect of molecular steric properties on the melting of quasi-two-dimensional solids is investigated by comparing results of molecular dynamics simulations of the melting of butane and hexane monolayers adsorbed on the basal-plane surface of graphite. These molecules differ only in their length......, being members of the n-alkane series [CH3(CH2)n−2CH3] where n=4 for butane and n=6 for hexane. The simulations employ a skeletal model, which does not include the hydrogen atoms explicitly, to represent the intermolecular and molecule–substrate interactions. Nearest-neighbor intramolecular bonds...... are fixed in length, but the molecular flexibility is preserved by allowing the bend and dihedral torsion angles to vary. The simulations show a qualitatively different melting behavior for the butane and hexane monolayers consistent with neutron and x-ray scattering experiments. The melting of the low...

Synergistic Effects of n-Hexane Fraction of Parkia biglobosa (Jacq. Bark Extract and Selected Antibiotics on Bacterial Isolates

Directory of Open Access Journals (Sweden)

Oluwatayo E. Abioye

2017-02-01

Full Text Available The incidence of resistance to commonly used antimicrobial agents by microbial pathogens demands increased effort in the development of effective ways of treating infections and diseases. The n-hexane fraction of lyophilized crude bark extract of Parkia biglobosa (Jacq. was prepared and, in combination with selected antibiotics, assayed for antimicrobial activity against some selected bacterial pathogens using time-kill assay. Protein leakage analysis of the combined agents was performed using Bradford protein quantification method. Determination of active compounds present in the n-hexane fraction was done using Fourier Transform Infrared Spectroscopy (FTIR. While time-kill assay detected 43.33% synergy; 56.67% indifference and no antagonism at 1/2 × minimum inhibitory concentration (MIC, 1 × MIC exhibited 55% synergy, 45% indifference and no antagonism. Protein leakages from the cells of selected bacteria ranged from 1.20 µg/mL to 256.93 µg/mL. The presence of a phenyl group, an aromatic ring and phenolic compounds in the n-hexane fraction was confirmed at 2162 cm−1–2020 cm−1, 1605 cm−1–1533 cm−1 and 1438 cm−1–1444 cm−1 spectra peaks, respectively. The observed antibiotic−n-hexane fraction synergistic interaction revealed the improved antibacterial activity of the selected antibiotics. Hence, exploration of a combination of antibiotics with plant secondary metabolites is hereby advocated in the global quest for means of combating infectious diseases caused by multidrug-resistant pathogens.

Evaluation of mechanism for antihypertensive and vasorelaxant effects of hexanic and hydroalcoholic extracts of celery seed in normotensive and hypertensive rats

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Faezeh Tashakori-Sabzevar

Full Text Available ABSTRACT Celery (Apium graveolens L., Apiaceae is one of the popular aromatic vegetables and part of the daily diet around the world. In this study, aqueous-ethanolic and hexane extracts of celery seed were prepared and the amount of n-butylphthalide, as an active component, was determined in each extract. Then the effects of hexanic extract on systolic, diastolic, mean arterial blood pressure and heart rate were evaluated in an invasive rat model. The vasodilatory effect and possible mechanisms of above mentioned extracts on aorta ring were also measured. High performance liquid chromatography analysis revealed that hexanic extract contains significantly higher amounts of n-butylphthalide, compared to aqueous-ethanolic extract. The results indicated that hexanic extract significantly decreased the systolic, diastolic, mean arterial blood pressure and heart rate in normotensive and hypertensive rats. Our data revealed that celery seed extract exerts its hypotensive effects through its bradycardic and vasodilatory properties. Moreover, the active components in celery seed extracts could induce their vasodilatory properties through Ca2+ channel blocking activity in endothelial and non-endothelial pathways and particularly by interference with the extra or intracellular calcium.

Thermal desorption studies of heterogeneous catalytic reactions--3. The stepwise mechanism of n-hexane dehydrocyclization (to benzene) over a Pt/Al/sub 2/O/sub 3/ catalyst

Energy Technology Data Exchange (ETDEWEB)

Rozanov, V V; Sklyarov, A V

1978-12-01

The interactions of n-hexane, benzene, and the possible intermediates of n-hexane dehydrocyclization by different mechanisms with a 0.68Vertical Bar3< Pt/..gamma..-Al/sub 2/O/sub 3/ catalyst and over pure ..gamma..-Al/sub 2/O/sub 3/ were studied by recording thermal desorption (TD) spectra of these compounds. The kinetic parameters, calculated from the TD data, for benzene formation from n-hexane, 1-hexene and 1,5-hexadiene coincided, suggesting a common reaction route involving these three species. TD spectra of methylcyclopentane indicated that this compound is not an important intermediate in n-hexane dehydrocyclization. These findings suggested that the process starts by two-step dehydrogenation of n-hexane to 1-hexene and 1,5-hexadiene and is followed by a rate-limiting step of hexadiene conversion. Formation of cyclohexadiene, the immediate precursor of benzene, occurs either by direct cyclization of hexadiene or via cyclohexene or hexatriene intermediates, but these routes are alternative rather than competing under the conditions studied.

Chemical Composition of Hexane Extract of Different Parts of Anthemis talyschensis and its Potential to Use in Sunscreen Products

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Alireza Motavalizadehkakhky

2016-06-01

Full Text Available In this study, both the presence and concentration of some unsaturated compounds in hexane extracts of different parts of Anthemis talyschensis showing absorption at wavelength 280-450 nm were surveyed, with the view of possibly using extracts of this plant in new formulations of sunscreen creams. The hexane extracts of flower, leaf and stem of A. talyschensis, collected from Northwest Iran, were obtained using a Soxhlet apparatus. The fatty acids were derivatized to methyl esters and were determined by gas chromatography/flame ionization detector (GC/FID and gas chromatography/mass spectrometry (GC/MS systems. The chemical analysis resulted in identification of 14, 9 and 29 constituents, comprising about 99.5, 97.1 and 98.2% of the total constituents in hexane extracts of flower, leaf and stem, respectively. The main unsaturated constituents in the hexane extract of A. talyschensis flower were 9, 12-octadecadienoic acid, 9-octadecenoic acid and 6, 9, 12-octadecatrienoic acid; while the leaf's extract contained 9, 12-octadecadienoic acid and 9-octadecenoic acid; no unsaturated compounds were detected in the stem. The ratios of unsaturated fatty acid /saturated fatty acid were 13.6, 9.3 and 0 in extracts of the flower, leaf and stem, respectively, but the total amounts in the leaf were much greater. It can be concluded the leaf extract is more likely to be suitable for producing sunscreens creams than others.

Influence of activated carbon characteristics on toluene and hexane adsorption: Application of surface response methodology

Science.gov (United States)

Izquierdo, Mª Teresa; de Yuso, Alicia Martínez; Valenciano, Raquel; Rubio, Begoña; Pino, Mª Rosa

2013-01-01

The objective of this study was to evaluate the adsorption capacity of toluene and hexane over activated carbons prepared according an experimental design, considering as variables the activation temperature, the impregnation ratio and the activation time. The response surface methodology was applied to optimize the adsorption capacity of the carbons regarding the preparation conditions that determine the physicochemical characteristics of the activated carbons. The methodology of preparation produced activated carbons with surface areas and micropore volumes as high as 1128 m2/g and 0.52 cm3/g, respectively. Moreover, the activated carbons exhibit mesoporosity, ranging from 64.6% to 89.1% the percentage of microporosity. The surface chemistry was characterized by TPD, FTIR and acid-base titration obtaining different values of surface groups from the different techniques because the limitation of each technique, but obtaining similar trends for the activated carbons studied. The exhaustive characterization of the activated carbons allows to state that the measured surface area does not explain the adsorption capacity for either toluene or n-hexane. On the other hand, the surface chemistry does not explain the adsorption results either. A compromise between physical and chemical characteristics can be obtained from the appropriate activation conditions, and the response surface methodology gives the optimal activated carbon to maximize adsorption capacity. Low activation temperature, intermediate impregnation ratio lead to high toluene and n-hexane adsorption capacities depending on the activation time, which a determining factor to maximize toluene adsorption.

Synthesis of zeolite-zeolite (mfi-fau) composite catalysts for the isomerization of n-hexane

International Nuclear Information System (INIS)

Ghouri, A.S; Usman, M.R.

2017-01-01

In this research work, the aim is to produce a relatively novel zeolite-zeolite (MFI-FAU) composite catalyst having better potential of catalyzing isomerization of lighter hydrocarbons such as light naphtha, n-pentane, n-hexane, n-heptane and mixture thereof. A series of zeolite-zeolite (MFI-FAU) composite catalysts have been synthesized by incorporating previous practices and techniques. The catalytic performance of as-synthesized zeolite-zeolite (MFI-FAU) composite catalysts have been investigated by isomerizing 95% pure n-hexane in conventional fixed bed flow micro-reactor at temperature 200-240 ºC under atmospheric pressure. In order to explore chemical and physical features of zeolite-zeolite (MFI-FAU) composite catalysts, they are examined and characterized using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectrometry (EDX), N2 adsorption-desorption measurements (BET, BJH, t-plot measurements) and Fourier transform infrared (FTIR) spectroscopy equipped with attenuated total reflectance (ATR) arrangements. (author)

Biodiesel from wet microalgae: extraction with hexane after the microwave-assisted transesterification of lipids.

Science.gov (United States)

Cheng, Jun; Huang, Rui; Li, Tao; Zhou, Junhu; Cen, Kefa

2014-10-01

A chloroform-free novel process for the efficient production of biodiesel from wet microalgae is proposed. Crude biodiesel is produced through extraction with hexane after microwave-assisted transesterification (EHMT) of lipids in wet microalgae. Effects of different parameters, including reaction temperature, reaction time, methanol dosage, and catalyst dosage, on fatty acids methyl esters (FAMEs) yield are investigated. The yield of FAME extracted into the hexane from the wet microalgae is increased 6-fold after the transesterification of lipids. The yield of FAME obtained through EHMT of lipids in wet microalgae is comparable to that obtained through direct transesterification of dried microalgae biomass with chloroform; however, FAME content in crude biodiesel obtained through EHMT is 86.74%, while that in crude biodiesel obtained through the chloroform-based process is 75.93%. EHMT ensures that polar pigments present in microalgae are not extracted into crude biodiesel, which leads to a 50% reduction in nitrogen content in crude biodiesel. Copyright © 2014 Elsevier Ltd. All rights reserved.

Supercritical SC-CO2 and Soxhlet n-Hexane Extract of Tunisian Opuntia ficus indica Seeds and Fatty Acids Analysis

OpenAIRE

Nizar Yeddes; Jamila Kalthoum Chérif; Amel Jrad; Danielle Barth; Malika Trabelsi-Ayadi

2012-01-01

The fatty acids profiles of Tunisian Opuntia ficus indica seeds (spiny and thornless form) were investigated. Results of supercritical carbon dioxide (SC-CO2) and soxhlet n-hexane extract were compared. Quantitatively, the better yield was obtained through soxhlet n-hexane: 10.32% (spiny) and 8.91% (thornless) against 3.4% (spiny) and 1.94% (thornless) by SC-CO2 extract (T = 40°C, P=180 bar, time = 135 mn, CO2 flow rate = 15 mL·s−1). Qualitatively, the main fatty acids components were the sam...

BRIONONIC ACID FROM THE HEXANE EXTRACT OF Sandoricum koetjape MERR STEM BARK (meliaceae

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Tukiran Tukiran

2010-06-01

Full Text Available An oleane-type triterpenoid, briononic acid was isolated from hexane extract of the stem bark of Sandoricum koetjape Merr. (Meliaceae. This structure had been established based on spectroscopic data (UV, IR, and NMR and by comparison with spectroscopic data of related compound that had been reported.   Keywords: Meliaceae, Oleane, Sandoricum koetjape Merr., Triterpenoid

[μ2-Bis(diphenylphosphanylhexane]bis[undecacarbonyl-triangulo-triruthenium(3 Ru—Ru] hexane monosolvate: crystal structure and Hirshfeld surface analysis

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Omar bin Shawkataly

2017-11-01

Full Text Available In the title cluster complex hexane solvate, [Ru6(C30H32P2(CO22]·C6H14, two Ru3(CO11 fragments are linked by a Ph2P(CH26PPh2 bridge with the P atoms equatorially disposed with respect to the Ru3 triangle in each case; the hexane solvent molecule is statistically disordered. The Ru...Ru distances span a relatively narrow range, i.e. 2.8378 (4 to 2.8644 (4 Å. The hexyl chain within the bridge has an all-trans conformation. In the molecular packing, C—H...O interactions between cluster molecules, and between cluster and hexane solvent molecules lead to a three-dimensional architecture. In addition, there are a large number of C[triple-bond]O...π(arene interactions in the crystal. The importance of the carbonyl groups in establishing the packing is emphasized by the contribution of 53.4% to the Hirshfeld surface by O...H/H...O contacts.

Muonated cyclohexadienyl radicals observed by level crossing resonance in dilute solutions of benzene in hexane subjected to muon-irradiation

International Nuclear Information System (INIS)

Walker, D.C.; Barnabas, M.V.; Venkateswaran, K.

1988-11-01

Benzene is used here as a scavenger of muonium to produce the muonated cyclohexadienyl radical in dilute solutions in n-hexane. The radical was identified by level crossing resonance spectroscopy (LCR) by observing the proton resonance of the -CHMu group occurring at 2.059T. Its yield is found to equal the sum of the muonium atom yield and the 'missing' muon yield in hexane (total 35% of the incident muons). Consequently, the complete dispersement of muons in different chemical associations is now accounted for in a saturated hydrocarbon liquid, and is seen to be similar to that in water

Solubility of Methane in the Mixture of Ethanol＋Hexane at High Pressures

Institute of Scientific and Technical Information of China (English)

华超; 马沛生; 夏淑倩; 白鹏

2005-01-01

Solubility data were first presented for methane in the mixture of ethanol-hexane at temperatures from 291.15K to 318.15K and pressures up to 12.00MPa. The experimental data were correlated by PR and PRSV equations of state with rms errors of about 0.051. The A-K and Y-W-A-K models were both used to estimate liquid molar volume under high pressure. The results were satisfactory.

PHYTOCHEMICAL ASSESSMENT ON N-HEXANE EXTRACT AND FRACTIONS OF Marsilea crenata Presl. LEAVES THROUGH GC-MS

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Burhan Ma'arif

2016-08-01

Full Text Available Estrogen deficiency causes various health problems in postmenopausal women, including osteoporosis. Phytoestrogen emerged as a potential alternative of estrogen with minimum side effects. Green clover (Marsilea crenata Presl. is a typical plant in East Java which suspected contains estrogen-like substances. The aim of this research was to report the phytochemical properties of M. crenata using GC-MS as a preliminary study. M. crenata leaves were dried and extracted with n-hexane, then separated using vacuum column chromatography to get four fractions, after that the n-hexane extract and four fractions were identified with GC-MS. The results of GC-MS analysis showed some compounds contained in M. crenata leaves like monoterpenoid, diterpenoid, fatty acid compounds, and other unknown compounds. The results obtained in this research indicated a promising potential of M. crenata as medicinal plants, especially as antiosteoporotic agent.

Comparative study of the radiolysis and photolysis of the hexane solutions of polychlorobiphenyls

International Nuclear Information System (INIS)

Abdullayev, E.T.; Gurbanov, M.A.; Jamalov, P.J.

2015-01-01

Model solutions of polychlorobiphenyls, containing 12 congeners in hexane were irradiated by γ-rays at 14-140 kGy absorption doses, as well as by UV-rays for 2-30 minutes using middle pressure mercury lamp (PRK-4, λ=253†546 nm), and the kinetics of the radiolytic PCBs degradation processes was investigated. The PCBs identification using a Gas Chromatography (Agilent Technologies 7820A)

Comparative Study of Various Preparation Methods of CuO–CeO2 Catalysts for Oxidation of n–Hexane and iso–Octane

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Ashutosh Mishra

2013-03-01

Full Text Available The complete oxidation of n-Hexane and iso-Octane was studied individually in a fixed bed tubular flow reactor over CuO-CeO2 catalysts synthesized via four different methods namely urea-nitrate combustion method, urea gelation/co-precipitation method, citric acid sol-gel method and co-impregnation method. Laser diffraction was employed in catalysts characterization. The results obtained from the complete conversion of n-Hexane and iso-Octane revealed that the CuO-CeO2 catalysts prepared by urea-nitrate combustion method (UNC showed the best performance than the catalysts prepared by other methods used in the present investigation. CuO-CeO2 catalysts prepared by UNC method achieve total n-Hexane and iso-Octane conversion to CO2 at lower temperatures of 280 0C and 340 0C respectively due to the larger surface area of the catalysts which increases the specific rate of reaction. © 2013 BCREC UNDIP. All rights reservedReceived: 30th October 2012; Revised: 30th November 2012; Accepted: 3rd December 2012[How to Cite: A. Mishra, B.D. Tripathi, A.K. Rai, R. Prasad (2013. Comparative Study of Various Preparation Methods of CuO–CeO2 Catalysts for Oxidation of n–Hexane and iso–Octane. Bulletin of Chemical Reaction Engineering & Catalysis, 7(3: 172-178. (doi:10.9767/bcrec.7.3.4076.172-178][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.7.3.4076.172-178 ] View in  |

Mutual solubility between hexane and three-n-butyl phosphate solvates of lanthanide(III) and thorium(IV) nitrates at various temperatures

International Nuclear Information System (INIS)

Keskinov, V.A.; Lishuk, V.V.; Pyartman, A.K.

2007-01-01

Phase diagrams of binary liquid systems of hexane-rare earth(III) nitrates solvates (rare earth - neodymium, gadolinium, yttrium, ytterbium, lutetium) and thorium(IV) with tri-n-butylphosphate are studied at different temperatures. Phase diagrams of binary systems consist of fields of homogeneous solutions and field of stratification into two liquid phases (I, II): phase I is enriched by hexane, and phase II - [Ln(NO 3 ) 3 (TBP) 3 ] (Ln=Nd, Gd, Y, Yb and Lu) or [Th(NO 3 ) 4 (TBP) 2 ]. Field of stratification into two liquid phases are decreased with growing temperature in binary systems [ru

Surface properties and catalytic performance of Pt/LaSrCoO4 catalysts in the oxidation of hexane

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Hua Zhong

2007-08-01

Full Text Available Perovskite-type La2 –xSrxCoO4 mixed oxides have been prepared by calcination at various temperatures of precipitates obtained from aqueous solutions in the presence of citric or ethylenediamintetraacetic (EDTA acids, and have been studied by X-ray diffraction (XRD, surface area (BET measurements, temperature programmed desorption (TPD, temperature programmed reduction (TPR and X-ray photoelectron spectroscopy (XPS. These oxides are catalysts for hexane oxidation, with the greatest activity for LaSrCoO4 calcined at 750 C. This has extensive oxygen vacancies and large internal surface area. Pt-modified LaSrCoO4 catalysts are significantly more active than the Pt-free system. Both surface and bulk phases of the preovskitetype oxides contribute to hexane oxidation.

High-pressure (vapour + liquid) equilibria for ternary systems composed by {(E)-2-hexenal or hexanal + carbon dioxide + water}: Partition coefficient measurement

International Nuclear Information System (INIS)

Bejarano, Arturo; López, Pablo I.; Valle, José M. del; Fuente, Juan C. de la

2015-01-01

Highlights: • A new apparatus based on a static–analytic method was assembled in this work. • This work reports high-pressure VLE data of (E)-2-hexenal or hexanal + CO 2 + water. • Data includes (CO 2 + water) partition coefficients of (E)-2-hexenal and hexanal. • High separation factors from water (∼10 4 ) were found especially for (E)-2-hexenal. • The data were obtained at T = (313, 323, and 333) K and pressures from (8 to 19) MPa. - Abstract: A new apparatus based on a static–analytic method assembled in this work was utilised to perform high-pressure (vapour + liquid) equilibria measurements of aqueous ternary systems. This work includes values of isothermal partition coefficients between CO 2 and water of two apple aroma constituents, (E)-2-hexenal and hexanal. Additionally, this work reports new experimental (vapour + liquid) equilibria measurements for the ternary systems (CO 2 + (E)-2-hexenal + water) and (CO 2 + hexanal + water), at fixed liquid phase composition (600 mg · kg −1 ), at temperatures of (313, 323 and 333) K and at pressures from (8 to 19) MPa. Vapour liquid interphase was checked and monitored visually for all the systems studied in this work. No liquid immiscibility was observed at the composition, temperatures and pressures studied. In order to suggest reasonable operation conditions for fractionation of aromas with dense carbon dioxide, partition coefficients of the aroma compounds between CO 2 and water along with their separation factors from water were calculated. Partition coefficients of (E)-2-hexenal between CO 2 and water were in the range of (6 to 91) and where found to be near six times higher than those of hexanal (9 to 17). Very high separation factors from water were observed (∼10 4 ) especially for (E)-2-hexenal. The highest separation factor, for both compounds, was found at a temperature of 313 K and pressures from (12 to 14) MPa

Amarginal contribution of selected carotenoids to the supression of UV-irradiation-induced lecithin peroxidation in hexane solution

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DRAGAN CVETKOVIC

2007-03-01

Full Text Available The aim of this work was to study the anticipated antioxidant role of four selected carotenoids in mixtures with lecithin lipoidal compounds in hexane solution, under continuous UV-irradiation in three different ranges (UV-A, UV-B and UV-C. Two carotenes (b-carotene and licopene and two xantophylls (lutein and neoxanthin were employed to control the lipid peroxidation process generated by UV-irradiation, by scavenging the involved free radicals. The results show that while carotenoids undergo a substantial, structural dependent destruction (bleaching, which is highly dependent on energy of the UV-photons, their contribution to the expected suppression of lecithin peroxidation is of marginal importance, not exceeding a maximum of 20%. The marginal antioxidant behaviour has been attributed to a highly unordered hexane solution, where the scavenging action of the carotenoids becomes less competitive.

Solid-phase microextraction method for the determination of hexanal in hazelnuts as an indicator of the interaction of active packaging materials with food aroma compounds.

Science.gov (United States)

Pastorelli, S; Valzacchi, S; Rodriguez, A; Simoneau, C

2006-11-01

Fatty foods are susceptible to lipid oxidation resulting in deterioration of product quality due to the generation of off-flavours. Hexanal is a good indicator of rancidity. Therefore, a method based on solid-phase microextraction (SPME) coupled to gas chromatograph with flame ionization detection was developed to determine hexanal formation in hazelnuts during storage. Optimum conditions were as follows: carboxen-polydimethylsiloxane 75 microm fibre, extraction time 10 min, equilibrium time 10 min and equilibrium temperature 60 degrees C. The effect of oxygen scavengers on the oxidation process was also evaluated by measuring hexanal formation in hazelnuts stored with/without oxygen absorber sachets. Oxygen scavengers were shown to reduce oxidation; however, analysis of the sachet revealed that other volatile compounds from the headspace were also absorbed.

Hexane cracking over steamed phosphated zeolite H-ZSM-5 : Promotional effect on catalyst performance and stability

NARCIS (Netherlands)

Van Der Bij, Hendrik E.; Meirer, Florian; Kalirai, Samanbir; Wang, Jian; Weckhuysen, Bert M.

2014-01-01

The nature behind the promotional effect of phosphorus on the catalytic performance and hydrothermal stability of zeolite H-ZSM-5 has been studied using a combination of 27Al and 31P MAS NMR spectroscopy, soft X-ray absorption tomography and n-hexane catalytic cracking, complemented with NH3

Seed oil extraction from red prickly pear using hexane and supercritical CO2 : assessment of phenolic compound composition, antioxidant and antibacterial activities.

Science.gov (United States)

Koubaa, Mohamed; Mhemdi, Houcine; Barba, Francisco J; Angelotti, Armel; Bouaziz, Fatma; Chaabouni, Semia Ellouz; Vorobiev, Eugène

2017-01-01

Investigating Opuntia species for their seed oil content is of much importance owing to their potential use for food and in cosmetic applications. These oils have an important content in unsaturated fatty acids as well as antioxidant compounds (e.g. polyphenols, vitamin E), which have been associated with the prevention of some chronic diseases. Moreover, Opuntia stricta oils possess important antimicrobial activities. For instance, the main focus of this study was to compare the effectiveness of conventional (hexane extraction) and novel (supercritical (SC)-CO 2 ) extraction methods for the recovery of oil and phenolic compounds from O. stricta seeds. The oil yield of both extracts was then compared and the polyphenol content and composition of both extracts were determined by liquid chromatography-high-resolution mass spectrometry. Additionally, antioxidant (DPPH assay) and antimicrobial activities (disc diffusion method) of O. stricta seed oils were determined. The oil yield (based on Soxhlet's method) of O. stricta seeds was determined using SC-CO 2 (49.9 ± 2.2%), and hexane (49.0 ± 1.5%). Although obtaining similar oil extraction yields using the two methods, the extracted oil using SC-CO 2 was more enriched in polyphenols (172.2 ± 11.9 µg gallic acid equivalents (GAE) g -1 oil) than that extracted using hexane (76.0 ± 6.9 µg GAE g -1 of oil). Polyphenol profiles showed that the SC-CO 2 process led to the yield of more compounds (45) than that using hexane extraction (11). Moreover, the antioxidant and antimicrobial activities of SC-CO 2 extract showed a high percentage of inhibition. SC-CO 2 extraction of O. stricta seed oil led to extraction of oil with a similar yield to that with hexane extraction, but with higher polyphenol content. The extract containing polyphenols exhibited high antioxidant and antibacterial properties, demonstrating their great potential as feedstock for high-oil quality. © 2016 Society of Chemical Industry. © 2016 Society of

Probing the surface swelling in ultra-thin supported polystyrene films during case II diffusion of n-hexane

NARCIS (Netherlands)

Ogieglo, Wojciech; Wormeester, Herbert; Wessling, Matthias; Benes, Nieck Edwin

2013-01-01

In situ time-resolved spectroscopic ellipsometry is used to study the dynamics of n-hexane diffusion into, and the corresponding induced swelling of, ultra-thin polystyrene films. The experimental conditions are carefully selected to facilitate the observation of anomalous Case II diffusion in the

Effect of temperature and pressure on excess electron mobility in n-hexane, 2,2,4-trimethylpentane, and tetramethylsilane

International Nuclear Information System (INIS)

Munoz, R.C.; Holroyd, R.A.

1986-01-01

Measurements of excess electron mobility are reported for liquid n-hexane, 2,2,4-trimethylpentane, and tetramethylsilane for pressures from 1 to 2500 bar and for temperatures from 18 to 120 0 C. For tetramethylsilane, a liquid that exhibits a high electron mobility, the mobility at constant density is proportional to T/sup -0.9/ between 25 and 100 0 C. The results are compared with the Basak--Cohen deformation potential theory. For n-hexane, where the mobility is low, Arrhenius behavior is observed. The isochoric activation energy increases with density. The results in this case are consistent with both the two-state and hopping models. In 2,2,4-trimethylpentane the mobility increases with increasing pressure at room temperature and decreases at high temperature. At 2500 bar and at intermediate temperatures (70--80 0 C) the mobility is approximately constant

GC-MS characterization of n-hexane soluble fraction from dandelion (Taraxacum officinale Weber ex F.H. Wigg.) aerial parts and its antioxidant and antimicrobial properties.

Science.gov (United States)

Ivanov, Ivan; Petkova, Nadezhda; Tumbarski, Julian; Dincheva, Ivayla; Badjakov, Ilian; Denev, Panteley; Pavlov, Atanas

2018-01-26

A comparative investigation of n-hexane soluble compounds from aerial parts of dandelion (Taraxacum officinale Weber ex F.H. Wigg.) collected during different vegetative stages was carried out. The GC-MS analysis of the n-hexane (unpolar) fraction showed the presence of 30 biologically active compounds. Phytol [14.7% of total ion current (TIC)], lupeol (14.5% of TIC), taraxasteryl acetate (11.4% of TIC), β-sitosterol (10.3% of TIC), α-amyrin (9.0% of TIC), β-amyrin (8.3% of TIC), and cycloartenol acetate (5.8% of TIC) were identified as the major components in n-hexane fraction. The unpolar fraction exhibited promising antioxidant activity - 46.7 mmol Trolox equivalents/g extract (determined by 1,1-diphenyl-2-picrylhydrazyl method). This fraction demonstrated insignificant antimicrobial activity and can be used in cosmetic and pharmaceutical industries.

Testicular atrophy and loss of nerve growth factor-immunoreactive germ cell line in rats exposed to n-hexane and a protective effect of simultaneous exposure to toluene or xylene

Energy Technology Data Exchange (ETDEWEB)

Nylen, P; Johnson, A C; Hoeglund, G; Ebendal, T; Eriksdotter-Nilsson, M; Henschen, A; Olson, L; Hansson, T; Kronevi, T; Kvist, U

1989-07-01

Testicular and germ cell line morphology in rats were studied 2 weeks, 10 months and 14 months after cessation of a 61-day inhalation exposure to 1000 ppm n-hexane. Androgen biosynthetic capacity of testis, testosterone blood concentration, vas deferens morphology and noradrenaline (NA) concentration, epididymal sperm morphology, and fertility were also studied. Severe testicular atrophy involving the seminiferous tubules with loss of the nerve growth factor (NGF) immunoreactive germ cell line was found. Total loss of the germ cell line was found in a fraction of animals up to 14 months post-exposure, indicating permanent testicular damage. No impairment of androgen synthesis or androgen dependent accessory organs was observed. Simultaneous administration of 1000 ppm n-hexane and 1000 ppm toluene, or 1000 ppm n-hexane and 1000 ppm xylene, did not cause germ cell line alterations or testicular atrophy. Toluene and xylene were thus found to protect from n-hexane induced testicular atrophy. (orig.).

The oxidation of 2,2,5-three methyl-6-spiro cyclo hexane di hydro pyranol-5(X CI)

International Nuclear Information System (INIS)

Nikitin, V.I.

1961-01-01

In this chapter of book author as a result of oxidation of 2,2,5-three methyl-6-spiro cyclo hexane di hydro pyranol-5 evolved acetone, cyclopentanone, formic acid, acetic acid, oxalic acid, α-oxi isobutyric acid and adipinic acids

Hexane neem leaf extract more potent than ethanol extract against Aspergillus flavus

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Jenny Hidayat

2015-12-01

Full Text Available BACKGROUND Aspergillus flavus is one of the causes of aspergillosis, with a high virulence and resistance to standard antifungals, resulting in a high mortality rate. Medicinal plants are increasingly used as they are relatively safer with minimal side effects. Previously we found that the ethanol extract of neem (Azadirachta indica A Juss leaves inhibits A. flavus growth in vitro. However, most chemical compounds with antifungal effect are nonpolar. The purpose of this research was to compare the antifungal effect of neem leaves extracted in a nonpolar solvent to that of leaves extracted in a polar solvent. METHODS An in vitro experimental research was conducted between October 2013 and January 2014. Neem leaves were extracted in ethanol or hexane at various concentrations. A macrodilution test with 48-hour incubation time was done in triplicate on 8 groups of samples. These comprised the neem leaf ethanol extract (NLEE at 0.5, 1.0, and 2.0 g/dL, neem leaf hexane extract (NLHE at 0.5, 1.0, and 2.0 g/dL, positive control, and negative control groups. Fungal growth was detected on Sabouroud dextrose agar. Statistical analysis used Chi square and Fisher’s exact test. RESULTS NLHE had a higher, but statistically non-significant, inhibitory effect on A. flavus than NLEE (p=0.996. At higher concentrations, the antifungal effect of NLHE is better than that of NLEE. CONCLUSION There is no significant difference in in-vitro inhibitory effectivity on A. flavus of neem leaves between extracts in polar and nonpolar solvents.

Hepatoprotective effects of hexane root extract of Alchornea laxiflora in sodium arsenate toxicity in wistar albino rats

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Esosa Samuel Uhunmwangho

2018-01-01

Full Text Available Background: Medicinal plants are have been used in the treatment of myriad disease conditions, Alchornea laxiflora is one of such medicinal plant. Aim: To investigate the hepatoprotective effect of hexane root extract of Alchornea laxiflora against sodium arsenate induced liver damage in wistar male rats. Setting and Design: Extraction and administration of bioactive extract. Materials and Methods: Extraction of air-dried ground root of Alchornea laxiflora was done by extracting 500 g with 500 cm of 95% hexane for 72 hrs.The animals (120-150 g were pre-treated with the extract at varying doses (0.1, 0.5, 1.0, 10, 50 and 100 mg/kg body weight for seven days orally prior to the intra-peritoneal administration of the toxicant (sodium arsenate at a dose of 2 mg/kg body weight at the eight day. Hepatoprotective activity of the extracts was evaluated by studying the Cytochrome b5content, Glutathione-S-transferase and 4- Nitroanisole-o-demethylase activities in the liver, Plasma levels of Alanine aminotransferase (AST, Alanine aminotransferase (ALT, Alkaline phosphatase (ALP and the levels of Total protein, Albumin, Globulin and Glutathione of the various groups. Statistical Analysis: The data were analysed with Microsoft excels (for windows 2007 and Student t-test and ANOVA. Result and Conclusion: The results suggest that pre-treatment of rats with hexane root extract of Alchornea laxiflora for seven days reduced the elevated levels of liver enzymes, reduced the levels of induced liver metabolizing enzymes and the levels of Total protein, Albumin, Globulin and Glutathione that was increased by the toxicity of sodium arsenate in rats and as such possess hepatoprotective effect against sodium arsenate.

New Methyltrimethoxysilane-(3-Mercaptopropyl)- Trimethoxysilane Coated Hollow Fiber-Solid Phase Micro extraction for Hexanal and Heptanal Analysis

International Nuclear Information System (INIS)

Siti Munirah Abd Wahib; Mohd Marsin Sanagi

2016-01-01

Determination of volatile organic compounds (VOCs) in various matrices is often accomplished using solid phase micro extraction (SPME) as a superior mode of extraction. Alternatively, another configuration of solid phase micro extraction (SPME) namely hollow fiber-solid phase micro extraction (HF-SPME) is a great approach to redress some limitations of the ordinary SPME fibers including fiber breakage, coating stripping and sample carry over. The HF-SPME technique highlights the use of hollow polypropylene (PP) membrane to hold and protect the adsorbent inside its lumen. Unlike the conventional SPME, the inexpensive HF device can be disposed after single use. Introducing extracting phase via sol-gel technology has gained great interest owing to its simple preparation method and promising way to obtain materials with good characteristics. In the present work, a new hybrid silica material based on methyltrimethoxysilane-(3-mercaptopropyl)trimethoxysilane (MTMOS-MPTMOS) was introduced as a new extractant of HF-SPME and the effectiveness of the proposed method was tested for analysis of hexanal and heptanal as the target VOC analytes. Preparation of the HF-SPME MTMOS-MPTMOS was simple in which the hybrid material was synthesized via sol-gel method and was self-polymerized in small segments of HF. Parameters affecting the efficiency of the HF-SPME MTMOS-MPTMOS in extracting both aldehydes were thoroughly investigated and analyzed by gas chromatography-flame ionization detection (GC-FID). It was found that the highest efficiency was achieved as the extraction was conducted in 30 min at a stirring rate of 1000 rpm in a 10 mL of sample solution whereby the back-extraction was performed via vortex for 3 min using 100 μL methanol as desorption solvent. Under the optimal conditions, linearity was observed over a range of 0.020-10.00 μg mL"-"1 with detection limits of 0.015 μg mL"-"1 and 0.010 μg mL"-"1 for hexanal and heptanal, respectively. The applicability of the HF

Chemical composition of the essential oil and hexane extract of Salvia chionantha and their antioxidant and anticholinesterase activities.

Science.gov (United States)

Tel, Gülsen; Oztürk, Mehmet; Duru, Mehmet Emin; Harmandar, Mansur; Topçu, Gülaçti

2010-11-01

The essential oil and methyl ester of hexane extract of Salvia chionantha Boiss. were analysed by GC and GC-MS. Totally, 54 components were detected in the essential oil and all of them were fully determined. Germacrene D (25.03%), β-caryophyllene (8.71%), spathulenol (5.86%) and α-humulene (4.82%) were identified as the major compounds. In the methylated hexane extract, 3-hydroxy hexadecanoic acid (39.39%), 3-hydroxy tetradecanoic acid (12.66%) and palmitic acid (12.02%) were the major fatty acids elucidated. The antioxidant activity of the essential oil and the hexane extract was determined by using four complementary test systems; namely, β-carotene-linoleic acid, DPPH() scavenging, ABTS(+)* scavenging, and CUPRAC assays. In β-carotene-linoleic acid assay, the extract showed 81.2±0.1% lipid peroxidation inhibition at 0.8 mg/mL concentration, while in ABTS(+)* assay the essential oil exhibited 77.4±0.5% inhibition at same concentration. Since, acetylcholinesterase and butyrylcholinesterase enzymes are taking place in pathogenesis of Alzheimer's disease, in vitro anticholinesterase activity of the essential oil and the extract was also studied spectrophotometrically. At 0.5mg/mL concentration, the essential oil showed moderate acetylcholinesterase (56.7±1.9%) and butyrylcholinesterase (41.7±2.9%) inhibitory activity, while the extract was only exhibited activity (63.1±0.8%) against butyrylcholinesterase enzyme. Hence, the essential oil may be useful as a moderate anticholinesterase agent, particularly against acetylcholinesterase. Copyright © 2010 Elsevier Ltd. All rights reserved.

Evaluation of (vapor + liquid) equilibria for the binary systems (1-octanol + cyclohexane) and (1-octanol + n-hexane), at low alcohol compositions

International Nuclear Information System (INIS)

Ovejero, Gabriel; Dolores Romero, M.; Diez, Eduardo; Lopes, Tania; Diaz, Ismael

2008-01-01

Isobaric (vapor + liquid) equilibrium at p = 101.32 kPa of pressure has been determined for the systems (1-octanol + cyclohexane) and (1-octanol + n-hexane), at low alcohol mole fractions. These data were satisfactorily correlated, using ASPEN PLUS commercial software, with Wilson, NRTL, and UNIQUAC activity coefficient models to obtain the binary interaction parameters of both mixtures. Also, UNIFAC group contribution method was employed to predict the equilibrium of both mixtures. With regression values an accurate knowledge of (vapor + liquid) equilibrium for both mixtures can be reached in a range of 1-octanol mole fractions less than 0.1. UNIFAC method provides acceptable results for (1-octanol + n-hexane) system but not for (1-octanol + cyclohexane) system

Evaluation of (vapor + liquid) equilibria for the binary systems (1-octanol + cyclohexane) and (1-octanol + n-hexane), at low alcohol compositions

Energy Technology Data Exchange (ETDEWEB)

Ovejero, Gabriel [Grupo de Catalisis y Procesos de Separacion (CyPS), Departamento de Ingenieria Quimica, Facultad de C. Quimicas, Universidsad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid (Spain)], E-mail: govejero@quim.ucm.es; Dolores Romero, M.; Diez, Eduardo; Lopes, Tania; Diaz, Ismael [Grupo de Catalisis y Procesos de Separacion (CyPS), Departamento de Ingenieria Quimica, Facultad de C. Quimicas, Universidsad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid (Spain)

2008-11-15

Isobaric (vapor + liquid) equilibrium at p = 101.32 kPa of pressure has been determined for the systems (1-octanol + cyclohexane) and (1-octanol + n-hexane), at low alcohol mole fractions. These data were satisfactorily correlated, using ASPEN PLUS commercial software, with Wilson, NRTL, and UNIQUAC activity coefficient models to obtain the binary interaction parameters of both mixtures. Also, UNIFAC group contribution method was employed to predict the equilibrium of both mixtures. With regression values an accurate knowledge of (vapor + liquid) equilibrium for both mixtures can be reached in a range of 1-octanol mole fractions less than 0.1. UNIFAC method provides acceptable results for (1-octanol + n-hexane) system but not for (1-octanol + cyclohexane) system.

Flourensia cernua: Hexane Extracts a Very Active Mycobactericidal Fraction from an Inactive Leaf Decoction against Pansensitive and Panresistant Mycobacterium tuberculosis

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Gloria María Molina-Salinas

2011-01-01

Full Text Available The efficacy of decoction in extracting mycobactericidal compounds from Flourensia cernua (Hojasé leaves and fractionation with solvents having ascending polarity was compared with that of (i ethanol extraction by still maceration, extraction with a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration, followed by fractionation with n-hexane, ethyl acetate, and n-butanol; (ii sequential extraction with n-hexane, ethyl acetate, and n-butanol, by still maceration, using a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration. The in vitro mycobactericidal activity of each preparation was measured against drug-sensitive (SMtb and drug-resistant (RMtb Mycobacterium tuberculosis strains. The results of which were expressed as absolute mycobactericidal activity (AMA. These data were normalized to the ΣAMA of the decoction fraction set. Although decoction was inactive, the anti-RMtb normalized ΣAMA (NAMA of its fractions was comparable with the anti-RMtb NAMA of the still maceration extracts and significantly higher than the anti-SMtb and anti-RMtb NAMAs of every other ethanol extract and serial extract and fraction. Hexane extracted, from decoction, material having 55.17% and 92.62% of antituberculosis activity against SMtb and RMtb, respectively. Although the mycobactericidal activity of decoction is undetectable; its efficacy in extracting F. cernua active metabolites against M. tuberculosis is substantially greater than almost all pharmacognostic methods.

Quasielastic neutron scattering and molecular dynamics simulation studies of the melting transition in butane and hexane monolayers adsorbed on graphite

DEFF Research Database (Denmark)

Hervig, K.W.; Wu, Z.; Dai, P.

1997-01-01

Quasielastic neutron scattering experiments and molecular dynamics (MD) simulations have been used to investigate molecular diffusive motion near the melting transition of monolayers of flexible rod-shaped molecules. The experiments were conducted on butane and hexane monolayers adsorbed...... comparison with experiment, quasielastic spectra calculated from the MD simulations were analyzed using the same models and fitting algorithms as for the neutron spectra. This combination of techniques gives a microscopic picture of the melting process in these two monolayers which is consistent with earlier...... neutron diffraction experiments. Butane melts abruptly to a liquid phase where the molecules in the trans conformation translationally diffuse while rotating about their center of mass. In the case of the hexane monolayer, the MD simulations show that the appearance of quasielastic scattering below T...

Preparation of catalysts based on Ce-Mn mixed oxide by coprecipitation for combustion of n-hexane

International Nuclear Information System (INIS)

Picasso, Gino; Zavala, Cesar; Cruz, Romulo; Sun Kou, Rosario; Lopez, Alcides

2013-01-01

Catalysts based on Ce-Mn mixed with different Ce/Mn molar ratios ranging from 0,5 to 2 have been prepared by coprecipitation at pH constant with ageing times of 4, 18 and 24 h for combustion of n-hexane. XRD patterns of the mixed oxides showed the majority presence of fluorite phase. Specific BET surface areas of mixed oxides were always higher than their single counterparts and their adsorption isotherm depicted a mesoporous surface of Type IV. TPR thermograms confirmed the presence of mixed oxide phase, whose profile shifted to smaller temperatures with increasing content of ceria. Catalytic tests were performed with 2000 ppm of n-hexane and WHSV of 80 h -1 in a fixed-bed reactor. For all samples, only CO 2 and water were observed at total conversion and no partial combustion products were obtained. Ce-Mn mixed oxides were more active than simple oxide samples no matter the aging time. Mixed samples presented thermal stability in contrast with simple ones. Mixed sample with Ce/Mn molar ratio of 2 depicted the highest activity probably due to higher surface area and better reducibility ability of mixed phase. (author)

Evaluation of the acute dermal exposure of the ethanolic and hexanic extracts from leaves of Schinus molle var. areira L. in rats.

Science.gov (United States)

Bras, Cristina; Gumilar, Fernanda; Gandini, Norberto; Minetti, Alejandra; Ferrero, Adriana

2011-10-11

Schinus molle var. areira L. (Anacardiaceae) is employed in herbal medicine for many conditions, including respiratory, urinary and menstrual disorders, and as a digestive stimulant, diuretic, astringent and antidepressant. It is also known for its topical use as wound healer, antiseptic, for skin disorders and as repellent and insecticide. In the present work, the acute dermal exposure to ethanolic and hexanic extracts from leaves of Schinus molle var. areira was studied in rats. A single dose of 2000 mg/kg of body weight of ethanolic and hexanic extracts from leaves was applied on the shaved skin of male and female rats. After 24h of exposure, the patch was removed and any sign of irritation was recorded. Behavioral and functional parameters in a functional observational battery and motor activity in an open field were assessed after the exposure to the extracts. Then, after 14 days of observation, animals were retested. Finally, histopathological studies were conducted on several organs. Slight signs of erythema and edema were observed in the skin site of exposure, but they disappeared after 48 h. The exposure to the hexanic extract produced an increase in parameters of activity, rearing and arousal assessed in the functional observational battery, which reversed after 14 days. On the other hand, the ethanolic extract caused an increase in locomotor activity, reflected in a higher number of rearings performed in the open field in the evaluation carried out on Day 14. No histopathological alterations were detected in the analyzed organs. The results show that the acute dermal exposure of the ethanolic and hexanic extracts from leaves of Schinus molle var. areira only causes a slight and reversible skin irritation, and a mild stimulatory effect in rats. All these indicate that the topical use of these extracts would be safe. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Antiproliferative activity of flower hexane extract obtained from Mentha spicata associated with Mentha rotundifolia against the MCF7, KB, and NIH/3T3 cell lines.

Science.gov (United States)

Nedel, Fernanda; Begnini, Karine; Carvalho, Pedro Henrique de Azambuja; Lund, Rafael Guerra; Beira, Fátima T A; Del Pino, Francisco Augusto B

2012-11-01

This study assessed the antiproliferative effect in vitro of the flower hexane extract obtained from Mentha spicata associated with Mentha rotundifolia against the human breast adenocarcinoma (MCF-7), human mouth epidermal carcinoma (KB), and mouse embryonic fibroblast (NIH 3T3) cell lines, using sulforhodamine B (SRB) assay. A cell density of 2×10(4)/well was seeded in 96-well plates, and samples at different concentrations ranging from 10 to 500 mg/mL were tested. The optical density was determined in an ELISA multiplate reader (Thermo Plate TP-Reader). Results demonstrated that the hexane extract presented antiproliferative activity against both the tumor cell lines KB and MCF-7, presenting a GI(50) (MCF-7=13.09 mg/mL), TGI (KB=37.76 mg/mL), and IL(50) (KB=291.07 mg/mL). Also, the hexane extract presented antiproliferative activity toward NIH 3T3 cells GI(50) (183.65 mg/mL), TGI (280.54 mg/mL), and IL(50) (384.59 mg/mL). The results indicate that the flower hexane extract obtained from M. spicata associated with M. rotundifolia presents an antineoplastic activity against KB and MCF-7, although an antiproliferative effect at a high concentration of the extract was observed toward NIH 3T3.

n-HEXANE NEUROPATHY DUE TO SHOEMAKING: REPORT OF FIVE CASES

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K. Sadeghniat

2005-04-01

Full Text Available n-hexane neuropathy has been described after glue sniffing and industrial exposure. Onset may be subacute and reminiscent of Guillain-Barre' syndrome. Five patients (15-18 years old presented with paresthesia, severe weakness of the extremities particularly lower extremities, as well as muscular atrophy, total areflexia and gait disturbances were admitted in hospital in March 2003. All of these boys were workers of a small footwear production unit. They worked as gluers of leather pieces. Nerve conduction velocity studies showed latency prolongation and cerebrospinal fluid (CSF analysis showed normal protein. In the workplace assessment, it was found that hexacarbone-containing adhesives were used in an inappropriate ventilated place and without any personal protective devices. These patients were re-examined 8 months later. Sensory and autonomic symptoms were alleviated but two of them still had gait disturbance and decreased reflexes.

Anti-cryptococcal activity of ethanol crude extract and hexane fraction from Ocimum basilicum var. Maria bonita: mechanisms of action and synergism with amphotericin B and Ocimum basilicum essential oil.

Science.gov (United States)

Cardoso, Nathalia N R; Alviano, Celuta S; Blank, Arie F; Arrigoni-Blank, Maria de Fátima; Romanos, Maria Teresa V; Cunha, Marcel M L; da Silva, Antonio Jorge R; Alviano, Daniela S

2017-12-01

Ocimum basilicum L. (Lamiaceae) has been used in folk medicine to treat headaches, kidney disorders, and intestinal worms. This study evaluates the anti-cryptococcal activity of ethanol crude extract and hexane fraction obtained from O. basilicum var. Maria Bonita leaves. The MIC values for Cryptococcus sp. were obtained according to Clinical and Laboratory Standards Institute in a range of 0.3-2500 μg/mL. The checkerboard assay evaluated the association of the substances tested (in a range of 0.099-2500 μg/mL) with amphotericin B and O. basilicum essential oil for 48 h. The ethanol extract, hexane fraction and associations in a range of 0.3-2500 μg/mL were tested for pigmentation inhibition after 7 days of treatment. The inhibition of ergosterol synthesis and reduction of capsule size were evaluated after the treatment with ethanol extract (312 μg/mL), hexane fraction (78 μg/mL) and the combinations of essential oil + ethanol extract (78 μg/mL + 19.5 μg/mL, respectively) and essential oil + hexane fraction (39.36 μg/mL + 10 μg/mL, respectively) for 24 and 48 h, respectively. The hexane fraction presented better results than the ethanol extract, with a low MIC (156 μg/mL against C. neoformans T 444 and 312 μg/mL against C. neoformans H99 serotype A and C. gattii WM779 serotype C). The combination of the ethanol extract and hexane fraction with amphotericin B and essential oil enhanced their antifungal activity, reducing the concentration of each substance needed to kill 100% of the inoculum. The substances tested were able to reduce the pigmentation, capsule size and ergosterol synthesis, which suggest they have important mechanisms of action. These results provide further support for the use of ethanol extracts of O. basilicum as a potential source of antifungal agents.

Radiolysis of fatty acid esters in n-hexane solution in an atmosphere of nitrogen

International Nuclear Information System (INIS)

Kimura, Kazuo; Shirai, Kazuo

1975-01-01

There have been several problems in food preservation by irradiation. Deterioration of food components by irradiation is one of the most substantial subjects. This investigation was undertaken as a basic experiment to discuss the radiolysis of lipids in food irradiation. In the previous paper, radiolytic examination on six of methyl esters of fatty acids in n-hexane solution in the presence of air was reported. In the present work the same samples-methyl stearate (C sub(18:0)), methyl oleate (C sub(18:1)), methyl linoleate (C sub(18:2)), methyl linolenate (C sub(18:3)), methyl arachidate (C sub(20:0)) and methyl arachidonate (C sub(20:4)) were examined in an atmosphere of nitrogen. Samples in n-hexane solution were sealed in glass ampules after substituted with nitrogen. Preparations were treated with 60 Co-gamma-radiation at dose from 1.8 x 10 6 to 7.1 x 10 6 rads. These preparations were analyzed by gas chromatography, infrared spectrophotometry and iodine value determination. The results were as follows: 1. Generally speaking saturated acids were stable and unsaturated were unstable. 2. In unsaturated series, the high unsaturated fatty acids were more labile to gamma-irradiation and the more increased doses induced the more drastic decompositions. 3. It was observed by infrared spectra that some isomerization from cis to trans configuration occured at double bond systems in unsaturated fatty acids. (auth.)

Experimental Determination of the Molar Absorption Coefficient of n-Hexane Adsorbed on High-Silica Zeolites.

Science.gov (United States)

Gatti, Giorgio; Olivas Olivera, Diana F; Sacchetto, Vittoria; Cossi, Maurizio; Braschi, Ilaria; Marchese, Leonardo; Bisio, Chiara

2017-09-06

Determination of the molar absorption coefficients of the CH 3 bending mode at ν˜ =1380 cm -1 (ϵ 1380 ) of n-hexane adsorbed from the gas phase on two different dealuminated zeolites is derived by a combination of IR spectroscopy and microgravimetric analysis. High-silica zeolite Y (HSZ-Y) and zeolite ZSM-5 (with SiO 2 /Al 2 O 3 ratios of 200 and 280, respectively) with different textural and surface features are selected to evaluate the effect of the pore structure and architecture on the value of ϵ 1380 of the adsorbed n-hexane. Experimental data indicate that the molecule experiences a different adsorption environment inside zeolites; thus resulting in a significant change of the dipole moment and very different ϵ 1380 values: (0.278±0.018) cm μmol -1 for HSZ-Y and (0.491±0.032) cm μmol -1 for ZSM-5. Experimental data are also supported by computational modeling, which confirms the effect of different matrices on the IR absorption intensity. This study reveals that the use of probe molecules for quantitative measurements of surface sites has to be judiciously adopted, especially if adsorption occurs in the restricted spaces of microporous materials. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

N,N'-(Hexane-1,6-diylbis(4-methyl-N-(oxiran-2-ylmethylbenzenesulfonamide: Synthesis via cyclodextrin mediated N-alkylation in aqueous solution and further Prilezhaev epoxidation

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Julian Fischer

2013-12-01

Full Text Available N-alkylation of N,N'-(hexane-1,6-diylbis(4-methylbenzenesulfonamide with allyl bromide and subsequent Prilezhaev reaction with m-chloroperbenzoic acid to give N,N'-(hexane-1,6-diylbis(4-methyl-N-(oxiran-2-ylmethylbenzenesulfonamide is described. This twofold alkylation was performed in aqueous solution, whereby α-, and randomly methylated β-cyclodextrin were used as adequate phase transfer catalysts and the cyclodextrin–guest complexes were characterized by 1H NMR and 2D NMR ROESY spectroscopy. Finally, the curing properties of the diepoxide with lysine-based α-amino-ε-caprolactam were analyzed by rheological measurements.

Gas barrier properties of hydrogenated amorphous carbon films coated on polyethylene terephthalate by plasma polymerization in argon/n-hexane gas mixture

Energy Technology Data Exchange (ETDEWEB)

Polonskyi, Oleksandr; Kylián, Ondřej, E-mail: ondrej.kylian@gmail.com; Petr, Martin; Choukourov, Andrei; Hanuš, Jan; Biederman, Hynek

2013-07-01

Hydrogenated amorphous carbon thin films were deposited by RF plasma polymerization in argon/n-hexane gas mixture on polyethylene terephthalate (PET) foils. It was found that such deposited films may significantly improve the barrier properties of PET. It was demonstrated that the principal parameter that influences barrier properties of such deposited films towards oxygen and water vapor is the density of the coatings. Moreover, it was shown that for achieving good barrier properties it is advantageous to deposit coatings with very low thickness. According to the presented results, optimal thickness of the coating should not be higher than several tens of nm. - Highlights: • a-C:H films were prepared by plasma polymerization in Ar/n-hexane atmosphere. • Barrier properties of coatings are dependent on their density and thickness. • Highest barrier properties were observed for films with thickness 15 nm.

Thermotropic phase transition in an adsorbed melissic acid film at the n-hexane-water interface

Science.gov (United States)

Tikhonov, A. M.

2017-06-01

A reversible thermotropic phase transition in an adsorption melissic acid film at the interface between n-hexane and an aqueous solution of potassium hydroxide (pH ≈ 10) is investigated by X-ray reflectometry and diffuse scattering using synchrotron radiation. The experimental data indicate that the interface "freezing" transition is accompanied not only by the crystallization of the Gibbs monolayer but also by the formation of a planar smectic structure in the 300-Å-thick adsorption film; this structure is formed by 50-Å-thick layers.

Spectacular Rate Enhancement of the Diels-Alder Reaction at the Ionic Liquid/n-Hexane Interface.

Science.gov (United States)

Beniwal, Vijay; Manna, Arpan; Kumar, Anil

2016-07-04

The use of the ionic liquid/n-hexane interface as a new class of reaction medium for the Diels-Alder reaction gives large rate enhancements of the order of 10(6) to 10(8) times and high stereoselectivity, as compared to homogeneous media. The rate enhancement is attributed to the H-bonding abilities and polarities of the ionic liquids, whereas the hydrophobicity of ionic liquids was considered to be the factor in controlling stereoselectivity. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Vapor pressure data for ethyl-2-methylbutyrate, hexanal and (E)-2-hexenal at a pressure range of (25 to 190) kPa

International Nuclear Information System (INIS)

Meneses, David A.; Bejarano, Arturo; Fuente, Juan C. de la

2014-01-01

Highlights: • Vapor pressures of three pure apple aroma constituents were measured. • Measurements were made over the temperature range of (362.1 to 429.9) K. • Constants of Antoine and Wagner type equations were fitted to the experimental data. • Relative deviations (rmsd) from the three vapor-pressure equations were <0.9%. • Contrast with literature showed discrepancies <9% among them and with this work. - Abstract: The saturated vapor pressures of pure ethyl-2-methylbutyrate, hexanal and (E)-2-hexenal, which are volatile compounds characteristic of apple aroma, were measured with a dynamic recirculation apparatus at a pressure range of (24.5 to 190.0) kPa. Measurements were made over the temperature range of (362.1 to 429.9) K for ethyl-2-methylbutyrate, (358.1 to 425.8) K for hexanal, and (373.5 to 446.2) K for (E)-2-hexenal. The maximum likelihood method was used to estimate the parameters of the Antoine equation, whereas the parameters of an extended Antoine equation and the Wagner equation were determined by non linear least square method. The three models showed root mean square deviations (rmsd) of 0.29%, 0.28%, and 0.27% for ethyl-2-methylbutyrate, 0.58%, 0.48%, and 0.38% for hexanal, and 0.89%, 0.62% and 0.36% for (E)-2-hexenal, respectively. Additionally, the experimental data and correlation were compared with those available in the literature

Effect of Enhanced Accessibility of Acid Sites in Micromesoporous Mordenite Zeolites on Hydroisomerization of n-Hexane

Czech Academy of Sciences Publication Activity Database

Pastvová, Jana; Kaucký, Dalibor; Morávková, Jaroslava; Rathouský, Jiří; Sklenák, Štěpán; Vorokhta, Maryna; Brabec, Libor; Pilař, Radim; Jakubec, Ivo; Tabor, Edyta; Klein, Petr; Sazama, Petr

2017-01-01

Roč. 7, č. 9 (2017), s. 5781-5795 ISSN 2155-5435 R&D Projects: GA ČR GA15-12113S; GA MŠk(CZ) LM2015073 Institutional support: RVO:61388955 ; RVO:61388980 ; RVO:67985891 Keywords : micromesoporous mordenite (MOR) zeolites * isomerization * n-hexane Subject RIV: CF - Physical ; Theoretical Chemistry; CA - Inorganic Chemistry (UACH-T); CA - Inorganic Chemistry (USMH-B) OBOR OECD: Physical chemistry; Inorganic and nuclear chemistry (UACH-T); Inorganic and nuclear chemistry (USMH-B) Impact factor: 10.614, year: 2016

Studies on the extraction of wheat germ oil by commercial hexane

Directory of Open Access Journals (Sweden)

El Kinawy, Omayma S.

2002-12-01

Full Text Available Extraction of an edible oil from wheat germ, an important byproduct of wheat milling industry in Egypt, using commercial hexane was studied. The extraction was carried out in a single and in two successive stages using different solvent-to-solid ratios from 2 to 6 m3/ ton. The results showed that a good oil recovery (about 75% can be achieved using 4 m3 hexane for each ton germ extracted in a single stage. This amount of solvent can be reduced to 2.5 m3/ ton if the process is carried out in two successive stages. The study has shown also that the amount of oil recovered from wheat germ is not significantly affected by heating the extraction mixture during the extraction process. The developments of free acids and peroxides in the oil during the storage period of wheat germ prior to extraction and during the hot extraction process were also investigated.Se ha estudiado la extracción de un aceite comestible a partir del germen de trigo, importante subproducto de la industria de la molienda del trigo en Egipto, usando hexano comercial. La extracción se llevó a cabo en una etapa única y en dos sucesivas, usando diferentes relaciones solvente-sólido desde 2 a 6 m3/ton. Los resultados mostraron que una buena recuperación de aceite (alrededor del 75% puede alcanzarse usando 4 m3 de hexano por cada tonelada de germen extraído en una etapa única. Esta cantidad de solvente puede reducirse a 2’5 m3/ton si el proceso se lleva a cabo en dos etapas sucesivas. El estudio mostró también que la cantidad de aceite recuperada a partir del germen de trigo no se afectó significativamente por el calentamiento de la mezcla durante el proceso de extracción. También se estudió la producción de ácidos libres y peróxidos en el aceite durante el período de almacenamiento del germen de trigo anterior a la extracción y durante el proceso de extracción en caliente

Experimental study and thermodynamic modeling for determining the effect of non-polar solvent (hexane)/polar solvent (methanol) ratio and moisture content on the lipid extraction efficiency from Chlorella vulgaris.

Science.gov (United States)

Malekzadeh, Mohammad; Abedini Najafabadi, Hamed; Hakim, Maziar; Feilizadeh, Mehrzad; Vossoughi, Manouchehr; Rashtchian, Davood

2016-02-01

In this research, organic solvent composed of hexane and methanol was used for lipid extraction from dry and wet biomass of Chlorella vulgaris. The results indicated that lipid and fatty acid extraction yield was decreased by increasing the moisture content of biomass. However, the maximum extraction efficiency was attained by applying equivolume mixture of hexane and methanol for both dry and wet biomass. Thermodynamic modeling was employed to estimate the effect of hexane/methanol ratio and moisture content on fatty acid extraction yield. Hansen solubility parameter was used in adjusting the interaction parameters of the model, which led to decrease the number of tuning parameters from 6 to 2. The results indicated that the model can accurately estimate the fatty acid recovery with average absolute deviation percentage (AAD%) of 13.90% and 15.00% for the two cases of using 6 and 2 adjustable parameters, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hepatoprotective effects of hexane root extract of Alchornea laxiflora in sodium arsenate toxicity in wistar albino rats

OpenAIRE

Esosa Samuel Uhunmwangho; Nurudeen Olajide Rasaq; Iyanuoluwa Olubukola Osikoya

2018-01-01

Background: Medicinal plants are have been used in the treatment of myriad disease conditions, Alchornea laxiflora is one of such medicinal plant. Aim: To investigate the hepatoprotective effect of hexane root extract of Alchornea laxiflora against sodium arsenate induced liver damage in wistar male rats. Setting and Design: Extraction and administration of bioactive extract. Materials and Methods: Extraction of air-dried ground root of Alchornea laxiflora was done by extracting 500 g with 50...

The hexane fraction of Ardisia crispa Thunb. A. DC. roots inhibits inflammation-induced angiogenesis

Science.gov (United States)

2013-01-01

Background Ardisia crispa (Myrsinaceae) is used in traditional Malay medicine to treat various ailments associated with inflammation, including rheumatism. The plant’s hexane fraction was previously shown to inhibit several diseases associated with inflammation. As there is a strong correlation between inflammation and angiogenesis, we conducted the present study to investigate the anti-angiogenic effects of the plant’s roots in animal models of inflammation-induced angiogenesis. Methods We first performed phytochemical screening and high-performance liquid chromatography (HPLC) fingerprinting of the hexane fraction of Ardisia crispa roots ethanolic extract (ACRH) and its quinone-rich fraction (QRF). The anti-inflammatory properties of ACRH and QRF were tested using the Miles vascular permeability assay and the murine air pouch granuloma model following oral administration at various doses. Results Preliminary phytochemical screening of ACRH revealed the presence of flavonoids, triterpenes, and tannins. The QRF was separated from ACRH (38.38% w/w) by column chromatography, and was isolated to yield a benzoquinonoid compound. The ACRH and QRF were quantified by HPLC. The LD50 value of ACRH was 617.02 mg/kg. In the Miles vascular permeability assay, the lowest dose of ACRH (10 mg/kg) and all doses of QRF significantly reduced vascular endothelial growth factor (VEGF)-induced hyperpermeability, when compared with the vehicle control. In the murine air pouch granuloma model, ACRH and QRF both displayed significant and dose-dependent anti-inflammatory effects, without granuloma weight. ACRH and QRF significantly reduced the vascular index, but not granuloma tissue weight. Conclusions In conclusion, both ACRH and QRF showed potential anti-inflammatory properties in a model of inflammation-induced angiogenesis model, demonstrating their potential anti-angiogenic properties. PMID:23298265

The growth of aligned carbon nanotubes on quartz substrate by spray pyrolysis of hexane

International Nuclear Information System (INIS)

Sadeghian, Zahra

2008-01-01

Vertically aligned multiwall carbon nanotubes were grown by spray pyrolysis of hexane as the carbon source in the presence of ferrocene as catalyst precursor on a quartz substrate. In recent work we used optimal experimental parameters for the feeding method, reactor conditions, reaction temperature and time, concentration of catalyst and flow rate of feed and gas. The process parameters were chosen so as to obtain multiwall carbon nanotubes and aligned multiwall carbon nanotubes. The tubes are around 15-80 nm in diameter. The morphology and structure of the samples were characterized by x-ray diffraction, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy analyses

Effect of the hexane extract of Piper auritum on insulin release from β-cell and oxidative stress in streptozotocin-induced diabetic rat.

Science.gov (United States)

Gutierrez, Rosa Martha Perez

2012-10-01

The large-leafed perennial plant Piper auritum known as Hoja Santa, is used for its leaves that because of their spicy aromatic scent and flavor have an important presence in Mexican cuisine, and in many regions, this plant is known for its therapeutic properties. In the present study, we investigated the effect of hexane, chloroform and methanol extracts from Piper auritum on cell culture system and the effect in streptozotocin-induced type 1 diabetic rats treated by 28 days on the physiological, metabolic parameters and oxidative stress. The hexane extract of P. auritum (HS) treatment significantly reduced the intake of both food, water and body weight loss as well as levels of blood glucose, serum cholesterol, triglycerides and increase HDL-cholesterol. After 4-week administration of HS antioxidant enzyme as SOD, CAT, GSH, GPx in pancreas were determined. These enzyme increased significantly compared with those of the diabetic rats control and normal animals. For all estimated, the results of HS treated groups leading to a restoration of the defense mechanism. The treatment also improves pancreatic TBARS-reactive substance level and serum NO and iNOS. To determine the insulin releasing activity, after extract treatment the serum and pancreatic sections were processed for examination of insulin-releasing activity using an immunocytochemistry kit. The results showed that administration of the hexane extract (200 and 400 mg/kg) exhibited a significant increase in serum and pancreas tissue insulin. Administration of streptozotocin decreased the insulin secretory activity in comparison with intact rats, but treatment with the HS extract increased significantly the activity of the beta cells in comparison with the diabetic control rats. The extract decreased serum glucose in streptozotocin-induced diabetic rats and increased insulin release from the beta cells of the pancreas. In cultured RIN-5F cells, we examined whether hexane extract of P. auritum would protect the

Process optimisation of microwave-assisted extraction of peony ( Paeonia suffruticosa Andr .) seed oil using hexane-ethanol mixture and its characterisation

Science.gov (United States)

Xiaoli Sun; Wengang Li; Jian Li; Yuangang Zu; Chung-Yun Hse; Jiulong Xie; Xiuhua Zhao

2016-01-01

Ethanol and hexane mixture agent microwave-assisted extraction (MAE) method was conducted to extract peony (Paeonia suffruticosa Andr.) seed oil (PSO). The aim of the study was to optimise the extraction for both yield and energy consumption in mixture agent MAE. The highest oil yield (34.49%) and lowest unit energy consumption (14 125.4 J g -1)...

1 - Aromatization of n-hexane and natural gasoline over ZSM-5 zeolite, 2- Wet catalytic oxidation of phenol on fixed bed of active carbon; 1 - Aromatisation de n-hexane et d'essence sur zeolithe ZSM-5, 2 - Oxydation catalytique en voie humide du phenol sur charbon actif

Energy Technology Data Exchange (ETDEWEB)

Suwanprasop, S.

2005-04-15

I - The production of aromatic hydrocarbons from n-hexane and natural gasoline over Pd loaded ZSM-5 zeolite in a tubular reactor was achieved under the suitable conditions at 400 deg. C, and 0.4 ml/min reactant feeding rate, employing ZSM-5 (0.5% Pd content) as a catalyst. Under these conditions, n-hexane and natural gasoline conversions were found to be 99.7% and 94.3%, respectively (with respective aromatic selectivity of 92.3% and 92.6%). II - Wet catalytic air oxidation of phenol over a commercial active carbon was studied in a three phase fixed bed reactor under mild temperature and oxygen partial pressure. Exit phenol concentration, COD, and intermediates were analysed. Oxidation of phenol was significantly improved when increasing operating temperature, oxygen partial pressure, and liquid space time, while up or down flow modes had only marginal effect. A complete model involving intrinsic kinetics and all mass transfer limitations gave convenient reactor simulation. (author)

Thermodiffusion, molecular diffusion and Soret coefficient of binary and ternary mixtures of n-hexane, n-dodecane and toluene.

Science.gov (United States)

Alonso de Mezquia, David; Wang, Zilin; Lapeira, Estela; Klein, Michael; Wiegand, Simone; Mounir Bou-Ali, M

2014-11-01

In this study, the thermodiffusion, molecular diffusion, and Soret coefficients of 12 binary mixtures composed of toluene, n-hexane and n-dodecane in the whole range of concentrations at atmospheric pressure and temperatures of 298.15 K and 308.15 K have been determined. The experimental measurements have been carried out using the Thermogravitational Column, the Sliding Symmetric Tubes and the Thermal Diffusion Forced Rayleigh Scattering techniques. The results obtained using the different techniques show a maximum deviation of 9% for the thermodiffusion coefficient, 8% for the molecular diffusion coefficient and 2% for the Soret coefficient. For the first time we report a decrease of the thermodiffusion coefficient with increasing ratio of the thermal expansion coefficient and viscosity for a binary mixture of an organic ring compound with a short n-alkane. This observation is discussed in terms of interactions between the different components. Additionally, the thermogravitational technique has been used to measure the thermodiffusion coefficients of four ternary mixtures consisting of toluene, n-hexane and n-dodecane at 298.15 K. In order to complete the study, the values obtained for the molecular diffusion coefficient in binary mixtures, and the thermodiffusion coefficient of binary and ternary mixtures have been compared with recently derived correlations.

Temperature-induced transition of the diffusion mechanism of n-hexane in ultra-thin polystyrene films, resolved by in-situ Spectroscopic Ellipsometry

NARCIS (Netherlands)

Ogieglo, Wojciech; Wormeester, Herbert; Wessling, Matthias; Benes, Nieck Edwin

2013-01-01

In-situ Spectroscopic Ellipsometry is used to study diffusion of liquid n-hexane in silicon wafer supported 150 nm thick polystyrene films, in the temperature range 16e28 C. In the higher part of this temperature range Case II diffusion is shown to be dominant. In this case the temporal evolution of

A LONG CHAIN ALCOHOL AND TWO STEROL COMPOUNDS FROM THE HEXANE EXTRACT OF STEM BARK OF Aglaia odorata Lour. (Meliaceae

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Tukiran Tukiran

2010-06-01

Full Text Available A long chain alcohol, 1-eicosanol together with two sterols, β-sitosterol and stigmasterol had been isolated from hexane extract of stem bark of pacar cina (Aglaia odorata Lour (Meliaceae. These structures had been established based on spectroscopic data (IR and NMR and by comparison to those of standard compounds.   Keywords: Aglaia odorata Lour, Alcohol, Meliaceae, Sterol

Response surface optimization for the transesterification of karanja oil using immobilized whole cells of Rhizopus oryzae in n-hexane system

Energy Technology Data Exchange (ETDEWEB)

Ganesan, Devanesan; Rajendran, Aravindan; Thangavelu, Viruthagiri [Annamalai University, Department of Chemical Engineering, Faculty of Engineering and Technology, Biochemical Engineering Laboratory, Annamalai Nagar, Tamil Nadu (India)

2012-03-15

Non-edible oils represent one of the most viable alternative feed stocks for the production of large volumes of biodiesel at cheaper cost in tropical countries. The objective of the present study is to investigate the ability of the immobilized whole cells of Rhizopus oryzae MTCC 262 to catalyze the biodiesel production from karanja oil in n-hexane system. Response surface methodology was employed to evaluate the effects of synthesis parameters, such as molar ratio of oil to alcohol, reaction temperature and reaction time on percentage biodiesel (methyl esters) yield. Transesterification was performed in shake flasks containing immobilized cells in the reaction mixture with 10% oil weight of n-hexane. The quadratic effects of molar ratio of oil to alcohol and reaction time proved to be the significant at 1% and 5% levels, respectively. The optimum synthesis conditions were found to be: molar ratio of oil to alcohol 1:2.73, reaction temperature 41.39 C and reaction time 73.97 h. Biodiesel yield (methyl ester) was 75.98 (wt.%) under the optimal conditions and the subsequent verification experiments with biodiesel yield of 78.0 (wt.%) confirmed the validity of the proposed model. (orig.)

COMPARATIVE STUDY OF CHEMICAL COMPOSITION, PHYSICO-CHEMICAL AND ANTIOXIDANT PROPERTIES OF OILS EXTRACTED BY TRADITIONAL AND HEXANE METHODS FROM TERMINALIA CATAPPA L. KERNELS

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Bérenger A. L. Ladele

2017-10-01

Full Text Available The comparative study of physico-chemical characteristics of Terminalia catappa L. kernel oils extracted by two methods has been done. The oil yields were 28.13 % and 61.78 % respectively for traditional and hexane methods and the fatty acid profiles showed palmitic acid (40.79 % and 40.03 % respectively oleic acid (25.55 % and 26.09 % respectively, linoleic acid (26.72 % and 26.64 % respectively and stearic acid (4.35 % and 4.49 % respectively as major components. The oils extracted by the two ways showed similar physico-chemical properties, good calorific values and non-toxicity against Artemia salina L. Oil obtained by traditional method exhibited more antioxidant capacity (1.40 than the hexane one (0.15. This traditional method helps to extract 45 % of the total oil. It gives oil free of organic solvent, with good physico-chemical properties that could be useful as edible oil and for industrial applications.

Fractionation of benzene/n-hexane mixtures by pervaporation using polyurethane membranes

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CUNHA V. S.

1999-01-01

Full Text Available In the present work polyurethane membranes obtained from different polyester/MDI-based polymers were used to separate benzene/n-hexane mixtures by pervaporation. In pervaporation experiments, with a 50% wt feed at room temperature, permeate fluxes in the range of 0.3 to 3.2 Kg/m2h (10 mm membrane thickness and selectivity in the range of 3.8 to 5.6 were obtained. The permeate was always enriched in benzene. Taking into account the compromise between flux and selectivity, the best performance membrane was selected for complementary sorption and pervaporation experiments. Results show that selectivity increases and the permeation flux decreases when the benzene concentration in the feed decreases. In the present application, results also show that sorption is the main factor for selectivity. Using the distillation azeotropic mixture as feed, almost no influence of temperature on selectivity was observed in the range of 25oC to 56oC. The permeate flux increases seven-fold, while selectivity remains constant near 8.0.

The liquid–liquid coexistence curves of {x dimethyl adipate + (1 − x) n-hexane} and {x dimethyl adipate + (1 − x) n-heptane} in the critical region

International Nuclear Information System (INIS)

Chen Zhiyun; Cai Li; Huang Meijun; Yin Tianxiang; An Xueqin; Shen Weiguo

2012-01-01

Highlights: ► Coexistence curves of (dimethyl adipate + n-hexane) (+n-heptane) were measured. ► The critical exponent β are consistent with the 3D-Ising value. ► The asymmetry of the coexistence curves were discussed by complete scaling theory. - Abstract: The liquid–liquid coexistence curves for (dimethyl adipate + n-hexane), (dimethyl adipate + n-heptane) have been measured, from which the critical amplitudes and the critical exponents are deduced. The critical exponent β corresponding to the coexistence curves are consistent with the 3D-Ising value. The experimental results have also been analyzed to determine the critical amplitudes of Wegner-correction terms when β and Δ are fixed at their theoretical values, and to examine the asymmetry of the diameters for the coexistence curves.

Production of C(3)/C(4) Olefins from n-Hexane: Conceptual design of a catalytic oxidative cracking process and comparison to steam cracking

NARCIS (Netherlands)

Boyadjian, C.A.; Seshan, Kulathuiyer; Lefferts, Leonardus; van der Ham, Aloysius G.J.; van den Berg, Henderikus

2011-01-01

A conceptual design of the catalytic oxidative cracking (COC) of hexane as a model compound of naphtha is reported. The design is based on experimental data which are elaborated through a structural design method to a process flow sheet. The potential of COC as an alternative to steam cracking (SC)

Anticholinergic, antihistaminic, and antiserotonergic activity of n-hexane extract of Zanthoxylum alatum seeds on isolated tissue preparations: An ex vivo study.

Science.gov (United States)

Saikia, Beenita; Barua, Chandana Choudhury; Haloi, Prakash; Patowary, Pompy

2017-01-01

The aim of this study was to evaluate anticholinergic, antihistaminic, and antiserotonergic activity of the n-hexane extract of the seeds of Zanthoxylum alatum (ZAHE) on isolated ileum of rat and guinea pig and fundus of rat. ZAHE was prepared using soxhlet extraction and cumulative concentration response curves were constructed using various doses on the tissues for acetylcholine (ACh), 5-hydroxytryptamine (5-HT), and histamine with or without n-hexane extract. Atropine, ketanserin, and pheniramine maleate were used as antagonists for ACh, serotonin, and histamine, respectively. ZAHE-induced concentration-dependent inhibition of isolated ileum and fundus in rat and ileum of guinea pig. The half maximal effective concentration (EC 50 ) of ACh in the presence of atropine (10 -6 M; P pheniramine maleate (10 -6 M; P < 0.01) and ZAHE (300 μg/ml; P < 0.01 and 1000 μg/ml; P < 0.05) was also significantly higher than EC 50 of histamine alone. From the study, it was observed that ZAHE shows significant anticholinergic, antiserotonergic, and antihistaminic activity. The study provides sufficient evidence that the seeds can be used in gastric disorders, cough, chest infection, etc., as per folklore claims.

Amélioration des méthodes de dosage de traces d’hexane résiduel dans les huiles végétales raffinées

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Lacoste Florence

2001-03-01

Full Text Available Afin d’améliorer la sensibilité et la répétabilité du dosage des traces d’hexane résiduel dans les corps gras pour des teneurs de l’ordre du mg/kg, une optimisation de la méthode décrite dans la norme Afnor NF T 60-257 a été entreprise en chromatographie en phase gazeuse. L’utilisation d’une colonne de type wide-bore à film épais, en couplage avec un appareil automatique d’espace de tête statique ou même en pratiquant l’analyse avec injection manuelle, permet de quantifier 0,25 mg/kg d’hexane technique. La linéarité de la réponse est très bonne dans le domaine de teneurs considéré, de 1 à 10 mg/kg. Les taux de récupération sont satisfaisants puisqu’ils sont compris entre 93 et 107 % pour les échantillons de concentration en hexane technique comprise entre 0,25 et 2 mg/kg. Les résultats témoignent également de la bonne répétabilité de cette méthode ; en effet, pour une concentration de 1 mg/kg, le coefficient de variation est d’environ 3 %.

Applications of the hexanic fraction of Agave sisalana Perrine ex Engelm (Asparagaceae: control of inflammation and pain screening

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Ricardo Jose Dunder

2013-05-01

Full Text Available The present study evaluated the anti-inflammatory and analgesic properties of Agave sisalana Perrine in classic models of inflammation and pain. The hexanic fraction of A. sisalana (HFAS was obtained by acid hydrolysis followed by hexanic reflux. Anti-inflammatory properties were examined in three acute mouse models (xylene ear oedema, hind paw oedema and pleurisy and a chronic mouse model (granuloma cotton pellet. The antinociceptive potential was evaluated in chemical (acetic-acid and thermal (tail-flick and hot-plate test models of pain. When given orally, HFAS (5, 10, 25 and 50 mg/kg reduced ear oedema (p < 0.0001; 52%, 71%, 62% and 42%, respectively. HFAS also reduced hind paw oedema at doses of 10 mg/kg and 25 mg/kg (p < 0.05; 42% and 58%, respectively and pleurisy at doses of 10 mg/kg and 25 mg/kg (41% and 50%, respectively. In a chronic model, HFAS reduced inflammation by 46% and 58% at doses of 10 mg/kg and 25 mg/kg, respectively. Moreover, this fraction showed analgesic properties against the abdominal writhing in an acetic acid model (at doses of 5-25 mg/kg with inhibitory rates of 24%, 54% and 48%. The HFAS also showed an increased latency time in the hot-plate (23% and 28% and tail-flick tests (61% and 66% for the 25 mg/kg and 50 mg/kg doses, respectively. These results suggest that HFAS has anti-inflammatory and analgesic properties.

Superior activity of non-interacting close acidic protons in Al-rich Pt/H-*BEA zeolite in isomerization of n-hexane

Czech Academy of Sciences Publication Activity Database

Sazama, Petr; Kaucký, Dalibor; Morávková, Jaroslava; Pilař, Radim; Klein, Petr; Pastvová, Jana; Tabor, Edyta; Sklenák, Štěpán; Jakubec, Ivo; Mokrzycki, Lukasz

2017-01-01

Roč. 533, MAR 2017 (2017), s. 28-37 ISSN 0926-860X R&D Projects: GA ČR GA15-12113S; GA MŠk(CZ) LM2015073 Institutional support: RVO:61388955 ; RVO:61388980 Keywords : Isomerization * Alkanes Hexane * Zeolites * Al-rich beta (*BEA) * Mordenite Subject RIV: CF - Physical ; Theoretical Chemistry; CA - Inorganic Chemistry (UACH-T) OBOR OECD: Physical chemistry; Inorganic and nuclear chemistry (UACH-T) Impact factor: 4.339, year: 2016

Anxiolytic-like actions of the hexane extract from leaves of Annona cherimolia in two anxiety paradigms: possible involvement of the GABA/benzodiazepine receptor complex.

Science.gov (United States)

López-Rubalcava, C; Piña-Medina, B; Estrada-Reyes, R; Heinze, G; Martínez-Vázquez, M

2006-01-11

A hexane extract of leaves of Annona cherimolia produced anxiolytic-like actions when administered to mice and tested in two animal models of anxiety: the mouse avoidance exploratory behavior and the burying behavior tests. In order to discard unspecific drug-actions on general activity, all treatments studied in the anxiety paradigms were also analyzed in the open field test. Results showed that A. cherimolia induced anxiolytic-like actions at the doses of 6.25, 12.5, 25.0 and 50.0 mg/kg. Picrotoxin (0.25 mg/kg), a GABA-gated chloride ion channel blocker, antagonized the anxiolytic-like actions of A. cherimolia, while a sub-effective dose of muscimol (0.5 mg/kg), a selective GABA(A) receptor agonist, facilitated the effects of a sub-optimal dose of A. cherimolia (3.12 mg/kg). Thus, the involvement of the GABA(A) receptor complex in the anxiolytic-like actions of A. cherimolia hexane extract is suggested. In addition the extract was also able to enhance the duration of sodium pentobarbital induced sleeping time. Taken together, results indicate that the hexane extract of A. cherimolia has depressant activity on the Central Nervous System and could interact with the GABA(A) receptor complex. On the other hand, the chromatographic separation of this extract led to the isolation of palmitone, and beta-sitosterol as major constituents. In addition a GC-MS study of some fractions revealed the presence of several compounds such beta-cariophyllene, beta-selinene, alpha-cubebene, and linalool that have been reported to show effects on behavior that could explain some of the extract effects.

Synthesis of highly reactive polyisobutylene catalyzed by EtAlCl 2/Bis(2-chloroethyl) ether soluble complex in hexanes

KAUST Repository

Kumar, Rajeev Ananda; Zheng, Bin; Huang, Kuo-Wei; Emert, Jack I.; Faust, Rudolf

2014-01-01

The polymerization of isobutylene (IB) to yield highly reactive polyisobutylene (HR PIB) with high exo-olefin content using GaCl3 or FeCl3·diisopropyl ether complexes has been previously reported.1 In an effort to further improve polymerization rates and exo-olefin content, we have studied ethylaluminum dichloride (EADC) complexes with diisopropyl ether, 2-chloroethyl ethyl ether (CEEE), and bis(2-chloroethyl) ether (CEE) as catalysts in conjunction with tert-butyl chloride as initiator in hexanes at different temperatures. All three complexes were readily soluble in hexanes. Polymerization, however, was only observed with CEE. At 0 °C polymerization was complete in 5 min at [t-BuCl] = [EADC·CEE] = 10 mM and resulted in PIB with ∼70% exo-olefin content. Studies on complexation using ATR FTIR and 1H NMR spectroscopy revealed that at 1:1 stoichiometry a small amount of EADC remains uncomplexed. By employing an excess of CEE, exo-olefin contents increased up to 90%, while polymerization rates decreased only slightly. With decreasing temperature, polymerization rates decreased while molecular weights as well as exo-olefin contents increased, suggesting that isomerization has a higher activation energy than β-proton abstraction. Density functional theory (DFT) studies on the Lewis acid·ether binding energies indicated a trend consistent with the polymerization results. The polymerization mechanism proposed previously for Lewis acid·ether complexes1 adequately explains all the findings. © 2014 American Chemical Society.

Synthesis of highly reactive polyisobutylene catalyzed by EtAlCl 2/Bis(2-chloroethyl) ether soluble complex in hexanes

KAUST Repository

Kumar, Rajeev Ananda

2014-03-25

The polymerization of isobutylene (IB) to yield highly reactive polyisobutylene (HR PIB) with high exo-olefin content using GaCl3 or FeCl3·diisopropyl ether complexes has been previously reported.1 In an effort to further improve polymerization rates and exo-olefin content, we have studied ethylaluminum dichloride (EADC) complexes with diisopropyl ether, 2-chloroethyl ethyl ether (CEEE), and bis(2-chloroethyl) ether (CEE) as catalysts in conjunction with tert-butyl chloride as initiator in hexanes at different temperatures. All three complexes were readily soluble in hexanes. Polymerization, however, was only observed with CEE. At 0 °C polymerization was complete in 5 min at [t-BuCl] = [EADC·CEE] = 10 mM and resulted in PIB with ∼70% exo-olefin content. Studies on complexation using ATR FTIR and 1H NMR spectroscopy revealed that at 1:1 stoichiometry a small amount of EADC remains uncomplexed. By employing an excess of CEE, exo-olefin contents increased up to 90%, while polymerization rates decreased only slightly. With decreasing temperature, polymerization rates decreased while molecular weights as well as exo-olefin contents increased, suggesting that isomerization has a higher activation energy than β-proton abstraction. Density functional theory (DFT) studies on the Lewis acid·ether binding energies indicated a trend consistent with the polymerization results. The polymerization mechanism proposed previously for Lewis acid·ether complexes1 adequately explains all the findings. © 2014 American Chemical Society.

Fabrication of Hydrophobic Membrane for the Separation of n-Hexane/Water Mixture Using Novel Oleophilic Nanoparticle and Kevlar Fabric, as a Superior Support

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Hanieh Karimnezhad

2017-07-01

Full Text Available The fabrication of functionalized membranes with hydrophobic/oleophilic surfaces for the elimination of n-hexane from water using para-aminobenzoate alumoxane, boehmite-epoxide and a novel nanoparticle, i.e., Stearate Alumoxane by a simple coating technique, is reported here. FTIR was used to characterize nanoparticles. SEM and contact angle measurement analyses were used to identify the nanocomposite membranes. The concentrations of oil in permeate and retentate were measured by UV/vis spectrophotometer. The morphology of Stearate alumoxane nanoparticles was investigated by means of SEM images. The composed film of nanoparticles on the Kevlar fabric was hydrophobic with water contact angle of ~ 145° and oleophilic with oil contact angle of ~ 0º. In addition, the membranes retained stable hydrophobicity and high separation efficiency even after employing for 6 times. Applying these properties, a setup was considered using the functionalized Kevlar fabric to separate oil through down to a collector and leave water drops. Our batch filtration system was exclusively gravity-driven. The achieved separation system can separate the oily water mixture (with the concentration of 20 % (v/v n-hexane in water, effectively with a separation efficiency of 84%.

Theoretical and Spectroscopic investigations of conformations, rotational barriers and scaled vibrations of 2,3-dimethyl hexane

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Aziz Aboulmouhajir

2017-01-01

Full Text Available The 2,3-dimethyl hexane conformational isomerism has been investigated in detail, based on HF, Post-HF and DFT calculations at different basis set. The effect of size of basis, ZPE, thermal contributions, electronic correlation and optimization methods on the conformational stability was discussed. The rotational barriers from the most stable conformer to the lowest energy secondary conformers and their correspondent inversion barriers at both HF and MP2 methods using 6-31G* basis set have also been approached. A normal mode calculation of the most and less-stable conformers using a scaled ab initio force field in terms of non-redundant local symmetry coordinates have been made to elucidate the conformational dependence of the vibrational spectra.

Ameliorative Effect of Hexane Extract of Phalaris canariensis on High Fat Diet-Induced Obese and Streptozotocin-Induced Diabetic Mice

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Rosa Martha Perez Gutierrez

2014-01-01

Full Text Available Obesity is one of the major factors to increase various disorders like diabetes. The present paper emphasizes study related to the antiobesity effect of Phalaris canariensis seeds hexane extract (Al-H in high-fat diet- (HFD- induced obese CD1 mice and in streptozotocin-induced mild diabetic (MD and severely diabetic (SD mice.AL-H was orally administered to MD and SD mice at a dose of 400 mg/kg once a day for 30 days, and a set of biochemical parameters were studied: glucose, cholesterol, triglycerides, lipid peroxidation, liver and muscle glycogen, ALP, SGOT, SGPT, glucose-6-phosphatase, glucokinase, hexokinase, SOD, CAT, GSH, GPX activities, and the effect on insulin level. HS-H significantly reduced the intake of food and water and body weight loss as well as levels of blood glucose, serum cholesterol, triglyceride, lipoprotein, oxidative stress, showed a protective hepatic effect, and increased HDL-cholesterol, serum insulin in diabetic mice. The mice fed on the high-fat diet and treated with AL-H showed inhibitory activity on the lipid metabolism decreasing body weight and weight of the liver and visceral adipose tissues and cholesterol and triglycerides in the liver. We conclude that AL-H can efficiently reduce serum glucose and inhibit insulin resistance, lipid abnormalities, and oxidative stress in MD and SD mice. Our results demonstrate an antiobesity effect reducing lipid droplet accumulation in the liver, indicating that its therapeutic properties may be due to the interaction plant components soluble in the hexane extract, with any of the multiple targets involved in obesity and diabetes pathogenesis.

Ameliorative Effect of Hexane Extract of Phalaris canariensis on High Fat Diet-Induced Obese and Streptozotocin-Induced Diabetic Mice.

Science.gov (United States)

Perez Gutierrez, Rosa Martha; Madrigales Ahuatzi, Diana; Horcacitas, Maria Del Carmen; Garcia Baez, Efren; Cruz Victoria, Teresa; Mota-Flores, Jose Maria

2014-01-01

Obesity is one of the major factors to increase various disorders like diabetes. The present paper emphasizes study related to the antiobesity effect of Phalaris canariensis seeds hexane extract (Al-H) in high-fat diet- (HFD-) induced obese CD1 mice and in streptozotocin-induced mild diabetic (MD) and severely diabetic (SD) mice.AL-H was orally administered to MD and SD mice at a dose of 400 mg/kg once a day for 30 days, and a set of biochemical parameters were studied: glucose, cholesterol, triglycerides, lipid peroxidation, liver and muscle glycogen, ALP, SGOT, SGPT, glucose-6-phosphatase, glucokinase, hexokinase, SOD, CAT, GSH, GPX activities, and the effect on insulin level. HS-H significantly reduced the intake of food and water and body weight loss as well as levels of blood glucose, serum cholesterol, triglyceride, lipoprotein, oxidative stress, showed a protective hepatic effect, and increased HDL-cholesterol, serum insulin in diabetic mice. The mice fed on the high-fat diet and treated with AL-H showed inhibitory activity on the lipid metabolism decreasing body weight and weight of the liver and visceral adipose tissues and cholesterol and triglycerides in the liver. We conclude that AL-H can efficiently reduce serum glucose and inhibit insulin resistance, lipid abnormalities, and oxidative stress in MD and SD mice. Our results demonstrate an antiobesity effect reducing lipid droplet accumulation in the liver, indicating that its therapeutic properties may be due to the interaction plant components soluble in the hexane extract, with any of the multiple targets involved in obesity and diabetes pathogenesis.

Thermodiffusion Coefficient Analysis of n-Dodecane /n-Hexane Mixture at Different Mass Fractions and Pressure Conditions

Science.gov (United States)

Lizarraga, Ion; Bou-Ali, M. Mounir; Santamaría, C.

2018-03-01

In this study, the thermodiffusion coefficient of n-dodecane/n-hexane binary mixture at 25 ∘C mean temperature was determined for several pressure conditions and mass fractions. The experimental technique used to determine the thermodiffusion coefficient was the thermograviational column of cylindrical configuration. In turn, thermophysical properties, such as density, thermal expansion, mass expansion and dynamic viscosity up to 10 MPa were also determined. The results obtained in this work showed a linear relation between the thermophysical properties and the pressure. Thermodiffusion coefficient values confirm a linear effect when the pressure increases. Additionally, a new correlation based on the thermodiffusion coefficient for n C12/n C6 binary mixture at 25 ∘C temperature for any mass fraction and pressures, which reproduces the data within the experimental error, was proposed.

Microwave-assisted extraction through an aqueous medium and simultaneous cleanup by partition on hexane for determining pesticides in agricultural soils by gas chromatography: A critical study

Energy Technology Data Exchange (ETDEWEB)

Fuentes, Edwar [Departamento de Quimica Inorganica y Analitica, Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Santiago, Casilla 233 (Chile)]. E-mail: edfuentes@ciq.uchile.cl; Baez, Maria E. [Departamento de Quimica Inorganica y Analitica, Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Santiago, Casilla 233 (Chile); Reyes, Dana [Departamento de Quimica Inorganica y Analitica, Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Santiago, Casilla 233 (Chile)

2006-09-25

A simple microwave-assisted extraction and partitioning method (MAEP) using water-acetonitrile and n-hexane for desorption and simultaneous partitioning, respectively, together with gas chromatography (GC) was studied to determine representative pesticides (trifluralin, metolachlor, chlorpyriphos and triadimefon) with a broad range of physico-chemical properties in agricultural soils. Three points were considered crucial in this study: instrumental and sample-associated factors affecting extraction of the target compounds were studied through experimental design; the spiking procedure at trace levels was carried out to reproduce the solute-soil sorption taking place in the environment as closely as possible; and results were analyzed taking into account the adsorption behaviour of the compounds on different kinds of soils. The complete analytical procedure proposed consisted of the MAEP of pesticides from 1.0 g of soil with 1 mL of 1:1 water/acetonitrile mixture, and 5 mL of hexane for trapping. The microwave heating program applied was 2 min at 250 W and 10 min at 900 W, and 130 deg. C maximum temperature. After extraction, the hexane layer was evaporated to dryness; the residue was re-dissolved and directly analyzed by gas chromatography electron capture detection (GC-ECD). Clean chromatograms were obtained without any additional cleanup step. Besides the four pesticides used to optimise MAEP, the method was applied to determine an additional group of pesticides (triallate, acetochlor, alachlor, endosulphan I and II, endrin, methoxychlor and tetradifon) in different soils. Most of the compounds studied were recovered in good yields with relative standard deviations (R.S.D.s) below 9% and detection limits ranged from 0.004 to 0.036 {mu}g g{sup -1}. The described method is efficient and fast to determine hydrophobic pesticides at ng g{sup -1} level in soil with different clay-to-organic matter ratios.

Microwave-assisted extraction through an aqueous medium and simultaneous cleanup by partition on hexane for determining pesticides in agricultural soils by gas chromatography: A critical study

International Nuclear Information System (INIS)

Fuentes, Edwar; Baez, Maria E.; Reyes, Dana

2006-01-01

A simple microwave-assisted extraction and partitioning method (MAEP) using water-acetonitrile and n-hexane for desorption and simultaneous partitioning, respectively, together with gas chromatography (GC) was studied to determine representative pesticides (trifluralin, metolachlor, chlorpyriphos and triadimefon) with a broad range of physico-chemical properties in agricultural soils. Three points were considered crucial in this study: instrumental and sample-associated factors affecting extraction of the target compounds were studied through experimental design; the spiking procedure at trace levels was carried out to reproduce the solute-soil sorption taking place in the environment as closely as possible; and results were analyzed taking into account the adsorption behaviour of the compounds on different kinds of soils. The complete analytical procedure proposed consisted of the MAEP of pesticides from 1.0 g of soil with 1 mL of 1:1 water/acetonitrile mixture, and 5 mL of hexane for trapping. The microwave heating program applied was 2 min at 250 W and 10 min at 900 W, and 130 deg. C maximum temperature. After extraction, the hexane layer was evaporated to dryness; the residue was re-dissolved and directly analyzed by gas chromatography electron capture detection (GC-ECD). Clean chromatograms were obtained without any additional cleanup step. Besides the four pesticides used to optimise MAEP, the method was applied to determine an additional group of pesticides (triallate, acetochlor, alachlor, endosulphan I and II, endrin, methoxychlor and tetradifon) in different soils. Most of the compounds studied were recovered in good yields with relative standard deviations (R.S.D.s) below 9% and detection limits ranged from 0.004 to 0.036 μg g -1 . The described method is efficient and fast to determine hydrophobic pesticides at ng g -1 level in soil with different clay-to-organic matter ratios

Photolytic debromination pathway of polybrominated diphenyl ethers in hexane by sunlight

International Nuclear Information System (INIS)

Wei, Hua; Zou, Yonghong; Li, An; Christensen, Erik R.; Rockne, Karl J.

2013-01-01

The objective of this work is to identify the photolytic debromination pathways of polybrominated diphenyl ethers (PBDEs). Thirteen PBDEs (BDEs 209, 208, 207, 206, 196, 183, 154, 153, 100, 99, 85, 47 and 28) in hexane were individually exposed to sunlight for up to 64 h. A total of 180 PBDEs were screened and 74 BDE debromination products were detected. The disappearance rate constant increased exponentially with increasing number of bromines. While no evident difference in debromination preference among ortho, meta and para bromines was found for heavier congeners, the vulnerability rank order was meta ≥ ortho > para for the lighter congeners (≤8 Br). The total molar mass of PBDEs continuously decreased during sunlight exposure, indicating PBDEs were transformed to non-PBDE compounds. A stochastic least squares debromination pathway model was developed to simulate the reactions and determine the yields to extend the results beyond the experimental observations. -- Highlights: ► 74 PBDEs are identified as the products of debromination via photolysis. ► Debromination is more likely at meta than para positions for PBDEs with ≤8 bromines. ► The stochastic least squares model results agree with and expand the experimental observations. ► Mass imbalance indicates a significant loss of PBDE mass during sunlight exposure. -- The PBDE debromination products and pathways identified in this work will assist in future studies on their environmental fate

Esterification of fatty acids using nylon-immobilized lipase in n-hexane: kinetic parameters and chain-length effects.

Science.gov (United States)

Zaidi, A; Gainer, J L; Carta, G; Mrani, A; Kadiri, T; Belarbi, Y; Mir, A

2002-02-28

The esterification of long-chain fatty acids in n-hexane catalyzed by nylon-immobilized lipase from Candida rugosa has been investigated. Butyl oleate (22 carbon atoms), oleyl butyrate (22 carbon atoms) and oleyl oleate (36 carbon atoms) were produced at maximum reaction rates of approximately equal to 60 mmol h(-1) g(-1) immobilized enzyme when the substrates were present in equimolar proportions at an initial concentration of 0.6 mol l(-1). The observed kinetic behavior of all the esterification reactions is found to follow a ping-pong bi-bi mechanism with competitive inhibition by both substrates. The effect of the chain-length of the fatty acids and the alcohols could be correlated to some mechanistic models, in accordance with the calculated kinetic parameters.

Pre-treatment by n-hexane extract of Phyllanthus niruri can alleviate paracetamol-induced damage of the rat liver

Directory of Open Access Journals (Sweden)

Md Jalaluddin Iqbal

2007-03-01

Full Text Available The present study aimed to obtain and evaluate remedy against viral hepatitis with Phyllanthus niruri (Bhui amla. Viral infection and toxic doses of paracetamol produce similar pattern of hepatotoxicity. Hepatotoxicity was induced by administering paracetamol (750 mg/kg body weight, single dose intraperitoneal into one group (group P of rats. Propylene glycol (vehicle was administered (2 ml into another group (group V of rats. 4 groups of P. niruri extract-pretreated (200 mg/kg body weight/day for 7 days rats were administered the same single dose of paracetamol on the 7th day. Extract of P. niruri were obtained through ethanol (E, hexane (H, dichloromethane (D and butane (B. Rat groups were V, P, E + P, H + P, D + P and B + P. Each group consisted of 6 rats and were sacrificed on the 9th day. Parameters for evaluation were biochemical (serum ALT, serum AST, serum ALP, serum bilirubin, hepatic reduced glutathione concentrations and hepatic histology. Propylene glycol (group V appeared non-toxic to the liver while significant degrees of centrilobuler hepatotoxicity was observed in group P paracetamol-treated rats. The E + P group suggested significant improvements in the serum parameters but these parameters appeared better alleviated in the H + P group. Hepatic reduced glutathione concentrations were replenished to the control level in both E + P and H + P groups. Hepatic histology supported biochemical and other observations in the P, E + P and H + P groups. Lesser degrees of alleviations were observed in the D + P and B + P groups. However, the hexane extract-pretreated group (H + P appeared to provide the most significant hepatoprotection against paracetamol induced hepatotoxicity in the rat. Titration of the dose following isolation of the active ingredient might offer complete alleviation.

Pre-treatment by n-hexane extract of Phyllanthus niruri can alleviate paracetamol-induced damage of the rat liver

Directory of Open Access Journals (Sweden)

Md. Jalaluddin Iqbal, Fawzia Z. Dewan, S.A.R.Chowdhury, M.I.R. Mamun,

2007-06-01

Full Text Available The present study aimed to obtain and evaluate remedy against viral hepatitis with Phyllanthus niruri (Bhui amla. Viral infection and toxic doses of paracetamol produce similar pattern of hepatotoxicity. Hepatotoxicity was induced by administering paracetamol (750 mg/kg body weight, single dose intraperitoneal into one group (group P of rats. Propylene glycol (vehicle was administered (2 ml into another group (group V of rats. Four groups of P. niruri extract-pretreated (200 mg/kg body weight/day for 7 days rats were administered the same single dose of paracetamol on the 7th day. Extract of P. niruri were obtained through ethanol (E, hexane (H, dichloromethane (D and butane (B. Rat groups were V, P, E + P, H + P, D + P and B + P. Each group consisted of 6 rats and were sacrificed on the 9th day. Parameters for evaluation were biochemical (serum ALT, serum AST, serum ALP, serum bilirubin, hepatic reduced glutathione concentrations and hepatic histology. Propylene glycol (group V appeared non-toxic to the liver while significant degrees of centrilobuler hepatotoxicity was observed in group P paracetamol-treated rats. The E + P group suggested significant improvements in the serum parameters but these parameters appeared better alleviated in the H + P group. Hepatic reduced glutathione concentrations were replenished to the control level in both E + P and H + P groups. Hepatic histology supported biochemical and other observations in the P, E + P and H + P groups. Lesser degrees of alleviations were observed in the D + P and B + P groups. However, the hexane extract-pretreated group (H + P appeared to provide the most significant hepatoprotection against paracetamol induced hepatotoxicity in the rat. Titration of the dose following isolation of the active ingredient might offer complete alleviation.

Chemical composition of essential oil and hexane extract and antioxidant activity of various extracts of Acmella uliginosa (Sw. Cass flowers from Indonesia

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Askal Maimulyanti

2016-07-01

Full Text Available Medicinal plants are rich sources of natural antioxidant which are used in the prevention and treatment of disease like artherosclerosis, heart stroke, diabetes and cancer and to delay the process of aging. Acmella uliginosa (Sw. Cass is an edible herb traditionally used in the treatment of many diseases. Analysis of volatile components in the flower extract used gas chromatography-mass spectrometry. The results showed the main components of the essential oil were caryophyllene (21.27%, caryophyllene oxide (15.49%, and 3-carene (10.73%. The main components of the hexane extract were N-isobutyl-2E,6Z,8E-decatrienamide (37.80%, α-pinene (4.98% and hexadacanoic acid-methyl ester (4.78%. The antioxidant activity of A. uliginosa (Sw. Cass flower from Indonesia was determined using 1,1, diphenyl-2-picryl hydrazine (DPPH free radical scavenging assay. The IC50 (defined as the total antioxidant necessary to decrease the initial DPPH radical by 50% of extracts was calculated. A comparative study determined that A. uliginosa (Sw. Cass in methanol extract showed higher antioxidant potential (IC50 = 96.83 μg/mL compared to ethyl acetate extract (IC50 = 123.46 μg/mL and n-hexane extract (905.92 μg/mL against DPPH free radicals.

One-Pot Synthesis of Dialkyl Hexane-1,6-Dicarbamate from 1,6-Hexanediamine, Urea, and Alcohol over Zinc-Incorporated Berlinite (ZnAlPO4 Catalyst

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Da-Lei Sun

2016-02-01

Full Text Available Dialkyl hexane-1,6-dicarbamate was synthesized, for the first time, by a one-pot reaction of 1,6-hexanediamine (HDA, urea, and alcohols, including methanol, ethanol, propanol, and butanol, in a self-designed batch reactor, using zinc-incorporated berlinite (ZnAlPO4 as a catalyst. The yield of dibutyl hexane-1,6-dicarbamate (2 was systematically investigated as a function of Zn/Al molar ratio, reaction temperature, reaction time, catalyst usage and urea/HDA/butanol molar ratio. Based on these studies, the optimized reaction conditions were as follows: molar ratio urea/HDA/butanol = 2.6:1:8.6, catalyst usage = 3.0 g, reaction temperature = 493 K, reaction time = 6 h and reaction pressure = 1.2 MPa; a yield of 2 of 89.7% was achieved over the ZnAlPO4 (molar ratio Zn/Al = 0.04 catalyst. The catalysts were characterized by X-ray photoelectric spectroscopy (XPS and scanning electron microscope (SEM. Additionally, based on these experimental results, it was also proposed that the catalysis recycle of the one-pot synthesis of 2 from urea, HDA, and butanol over the ZnAlPO4 catalyst.

Preparation of catalysts based on Cu-Mn for combustion of n-hexane

International Nuclear Information System (INIS)

Picasso, Gino; Belleza, Freddy; Zavala, Cesar; Lopez, Alcides; Sun Kou, Rosario

2014-01-01

Catalysts based on Cu-Mn mixed oxides (with molar ratio Cu/Mn in the range of 0,33 to 3) have been prepared by sol-gel method of self-combustion for removal of n-hexane. Two combustion agents, citric acid and ethylenglycol, were applied to study their influence in the final catalyst. Additionally, simple oxides have been synthesized using the same procedure for comparison reasons. The catalysts were characterized by X-ray diffraction (XRD) and sorption of N_2 (BET method). All samples depicted surfaces, preferentially assigned to mesoporosity whose values ranged from 4 to 50 m"2/g. All XRD difractograms of mixed samples showed the presence of a good crystalinity indepently of composition, with the formation of spinel-hopcalite phase meanwhile Mn and Cu simple oxide showed peaks attributed to Mn_O_3, Mn_3O_4 and CuO, respectively. Curves of activity, measured as number of VOC molecules converted per hour and per gram of catalyst, considering the specific surface, showed that mixed oxides with more Mn content were the best, additionally, the sample prepared from citric acid was more active than the corresponding values to simple oxides, probably due to the better specific surface and the better spinel-hopcalite structure obtained. (author)

Liposomal Formulation of Turmerone-Rich Hexane Fractions from Curcuma longa Enhances Their Antileishmanial Activity

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Ana Claudia F. Amaral

2014-01-01

Full Text Available Promastigote forms of Leishmania amazonensis were treated with different concentrations of two fractions of Curcuma longa cortex rich in turmerones and their respective liposomal formulations in order to evaluate growth inhibition and the minimal inhibitory concentration (MIC. In addition, cellular alterations of treated promastigotes were investigated under transmission and scanning electron microscopies. LipoRHIC and LipoRHIWC presented lower MIC, 5.5 and 12.5 μg/mL, when compared to nonencapsulated fractions (125 and 250 μg/mL, respectively, and to ar-turmerone (50 μg/mL. Parasite growth inhibition was demonstrated to be dose-dependent. Important morphological changes as rounded body and presence of several roles on plasmatic membrane could be seen on L. amazonensis promastigotes after treatment with subinhibitory concentration (2.75 μg/mL of the most active LipoRHIC. In that sense, the hexane fraction from the turmeric cortex of Curcuma longa incorporated in liposomal formulation (LipoRHIC could represent good strategy for the development of new antileishmanial agent.

Liposomal Formulation of Turmerone-Rich Hexane Fractions from Curcuma longa Enhances Their Antileishmanial Activity

Science.gov (United States)

Amaral, Ana Claudia F.; Gomes, Luciana A.; Silva, Jefferson Rocha de A.; Ferreira, José Luiz P.; Ramos, Aline de S.; Rosa, Maria do Socorro S.; Vermelho, Alane B.; Rodrigues, Igor A.

2014-01-01

Promastigote forms of Leishmania amazonensis were treated with different concentrations of two fractions of Curcuma longa cortex rich in turmerones and their respective liposomal formulations in order to evaluate growth inhibition and the minimal inhibitory concentration (MIC). In addition, cellular alterations of treated promastigotes were investigated under transmission and scanning electron microscopies. LipoRHIC and LipoRHIWC presented lower MIC, 5.5 and 12.5 μg/mL, when compared to nonencapsulated fractions (125 and 250 μg/mL), respectively, and to ar-turmerone (50 μg/mL). Parasite growth inhibition was demonstrated to be dose-dependent. Important morphological changes as rounded body and presence of several roles on plasmatic membrane could be seen on L. amazonensis promastigotes after treatment with subinhibitory concentration (2.75 μg/mL) of the most active LipoRHIC. In that sense, the hexane fraction from the turmeric cortex of Curcuma longa incorporated in liposomal formulation (LipoRHIC) could represent good strategy for the development of new antileishmanial agent. PMID:25045693

Synthesis and Evaluation of Bicyclo[3.1.0]hexane-Based UDP-Galf Analogues as Inhibitors of the Mycobacterial Galactofuranosyltransferase GlfT2

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Todd L. Lowary

2016-08-01

Full Text Available UDP-galactofuranose (UDP-Galf is the donor substrate for both bifunctional galactofuranosyltransferases, GlfT1 and GlfT2, which are involved in the biosynthesis of mycobacterial galactan. In this paper, a group of UDP-Galf mimics were synthesized via reductive amination of a bicyclo[3.1.0]hexane-based amine by reacting with aromatic, linear, or uridine-containing aldehydes. These compounds were evaluated against GlfT2 using a coupled spectrophotometric assay, and were shown to be weak inhibitors of the enzyme.

Synthesis of highly reactive polyisobutylene with FeCl3/ether complexes in hexane; kinetic and mechanistic studies

KAUST Repository

Kumar, Rajeev Ananda; De, Priyadarsi; Zheng, Bin; Huang, Kuo-Wei; Emert, Jack I.; Faust, Rudolf

2015-01-01

The kinetics and mechanism of the polymerization of isobutylene catalyzed by FeCl3·ether complexes in hexane at 0°C were investigated. The polymerization rates increased in the diisopropyl ether< 2-chloroethyl ethyl ether < bis(2-chloroethyl) ether order, attributed to electronic effects. The polymerization rates increased with increasing initiator and catalyst concentrations. The first order plots, however, deviated from the linear suggesting that the cation concentration decreases with time. The previously proposed mechanism is inadequate to explain this finding. The decrease in the polymerization rate with time is explained by the low solubility of the H+ROR′FeCl4 - complexes that precipitate during polymerization. Based on mechanistic studies the revised mechanism now also includes the equilibrium H+ROR′FeCl4 - ⇋ HCl + FeCl3·ROR′.

Crystal structure of the formal 20 electron zirconocene pentafulvene complex Cp2Zr(η5,η1-adamantylidenepentafulvene:toluene:n-hexane = 1:0.125:0.125

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Malte Fischer

2017-12-01

Full Text Available The crystal structure of a solvated zirconocene pentafulvene complex with a bulky adamantylidene substitution pattern, namely (η5,η1-adamantylidenepentafulvenebis(η5-cyclopentadienylzirconium(IV–toluene–n-hexane (8/1/1, [Zr(C15H18(C5H52]·0.125C7H8·0.125C6H14, is reported. Reducing zirconocene dichloride with magnesium results in the formation of a low-valent zirconocene reagent that reacts readily with adamantylidenepentafulvene to give the aforementioned complex. Single crystal X-ray diffraction proves the dianion-like η5:η1 binding mode of the fulvene ligand to the central ZrIV atom. The asymmetric unit contains four independent molecules of [η5:η1-adamantylidenepentafulvene]bis[(η5-cyclopentadienyl]zirconium(IV, together with half a molecule of toluene disordered with half a molecule of n-hexane (the solvent molecules have no direct influence on the complex. In each of the four complex molecules, the central ZrIV atom has a distorted tetrahedral coordination environment. The measured crystal consisted of two domains with a refined ratio of 0.77:0.23.

Catalytic oxidation of n-hexane promoted by Ce1−xCuxO2 catalysts prepared by one-step polymeric precursor method

International Nuclear Information System (INIS)

Araújo, Vinícius D.; Lima, Maurício M. de; Cantarero, Andrés; Bernardi, Maria I.B.; Bellido, Jorge D.A.; Assaf, Elisabete M.; Balzer, Rosana; Probst, Luiz F.D.; Fajardo, Humberto V.

2013-01-01

Ceria-supported copper catalysts (Ce 1−x Cu x O 2 , with x (mol) = 0, 0.01, 0.03, 0.05 and 0.10) were prepared in one step through the polymeric precursor method. The textural properties of the catalysts were investigated by X-ray diffraction (XRD), Rietveld refinement, N 2 -physisorption (BET surface area), electron paramagnetic resonance (EPR), UV–visible diffuse reflectance and photoluminescence spectroscopies and temperature-programmed reduction (TPR). In a previous study ceria-supported copper catalysts were found to be efficient in the preferential oxidation of CO. In this study, we extended the catalytic application of Ce 1−x Cu x O 2 systems to n-hexane oxidation and it was verified that the catalysts were highly efficient in the proposed reaction. The best performance (up to 95% conversion) was observed for the catalysts with low copper loads (Ce 0.97 Cu 0.03 O 2 and Ce 0.99 Cu 0.01 O 2 , respectively). The physicochemical characterizations revealed that these behaviors could be attributed to the copper species present in the catalysts and the interaction between CuO and CeO 2 , which vary according to the copper content. - Highlights: • Synthesis of CuO/CeO2 catalysts by the one-step polymeric precursor method. • 95% n-hexane conversion on Ce0.97Cu0.03O2 catalyst. • Redox properties play a key role in the catalytic performance

Hydroformylation of olefins and reductive carbonylation of aryl halides with syngas formed ex situ from dehydrogenative decarbonylation of hexane-1,6-diol

DEFF Research Database (Denmark)

Christensen, Stig Holden; Olsen, Esben Paul Krogh; Rosenbaum, Jascha

2014-01-01

A variety of primary alcohols have been investigated as convenient substrates for the ex situ delivery of carbon monoxide and molecular hydrogen in a two-chamber reactor. The gaseous mixture is liberated in one chamber by an iridium-catalysed dehydrogenative decarbonylation of the alcohol...... and then consumed in the other chamber in either a rhodium-catalysed hydroformylation of olefins or a palladium-catalysed reductive carbonylation of aryl halides. Hexane-1,6-diol was found to be the optimum alcohol for both reactions where moderate to excellent yields were obtained of the product aldehydes...

Spondias purpurea L. (Anacardiaceae: Antioxidant and Antiulcer Activities of the Leaf Hexane Extract

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Cynthia Layse Ferreira de Almeida

2017-01-01

Full Text Available Spondias purpurea is used in folk medicine to treat diarrhea and diuresis. The objective of this study was to evaluate the phytochemical profile and antioxidant and antiulcer activities of the hexane extract of the leaves of S. purpurea (SpHE. Phytochemical profile was evaluated via thin layer chromatography (TLC and HPLC. SpHE was screened for antioxidant activities using DPPH, ABTS, FRAP, and phosphomolybdenum assays. To determine its antiulcer properties, animals were pretreated with injured control, lansoprazole, ranitidine, carbenoxolone, or SpHE (12.5, 25, and 50 mg/kg and were screened; acute ulcers were induced by HCl/ethanol, absolute ethanol, and nonsteroidal anti-inflammatory drug (NSAID. TLC revealed the presence of flavonoids, whereas HPLC analysis showed the presence of caffeic acid and epigallocatechin. The phenolic compounds and in vitro assays showed antioxidant activity. After gastric ulcer induction by using HCl/ethanol, SpHE reduced the area of ulcerative lesions by 82, 91, and 88%, respectively. In ethanol, SpHE reduced the area of ulcerative lesions by 77, 93, and 92%, respectively. In the NSAID, the percentages of protection were 70, 76, and 78%, respectively. SpHE promoted the minimization of ulcers, increased the levels of reduced glutathione, and decreased tumor necrosis factor. S. purpurea has antioxidant and antiulcer properties.

Chemical kinetic insights into the ignition dynamics of n-hexane

KAUST Repository

Tingas, Alexandros

2017-10-13

Normal alkanes constitute a significant fraction of transportation fuels, and are the primary drivers of ignition processes in gasoline and diesel fuels. Low temperature ignition of n-alkanes is driven by a complex sequence of oxidation reactions, for which detailed mechanisms are still being developed. The current study explores the dynamics of low-temperature ignition of n-hexane/air mixtures, and identifies chemical pathways that characterize the combustion process. Two chemical kinetic mechanisms were selected as a comparative study in order to better understand the role of specific reaction sequences in ignition dynamics: one mechanism including a new third sequential O2 addition reaction pathways (recently proposed by Wang et al. 2017), while the other without (Zhang et al. 2015). The analysis is conducted by applying tools generated from the computational singular perturbation (CSP) approach to two distinct ignition phenomena: constant volume and compression ignition. In both cases, the role of the third sequential O2 addition reactions proves to be significant, although it is found to be much more pronounced in the constant volume cases compared to the HCCI. In particular, in the constant volume ignition case, reactions present in the third sequential O2 addition reaction pathways (e.g., KDHP  →  products + OH) contribute significantly to the explosivity of the mixture; when accounted for along with reactions P(OOH)2 + O2  →  OOP(OOH)2 and OOP(OOH)2  →  KDHP + OH, they decrease ignition delay time of the mixture by up to 40%. Under HCCI conditions, in the first-stage ignition, the third-O2 addition reactions contribute to the process, although their role decays with time and becomes negligible at the end of the first stage. The second ignition stage is dominated almost exclusively by hydrogen-related chemistry.

Excess molar volumes and deviation in viscosities of binary liquid mixtures of acrylic esters with hexane-1-ol at 303.15 and 313.15K

OpenAIRE

Patil, Sujata S.; Mirgane, Sunil R.; Arbad, Balasaheb R.

2014-01-01

Densities and viscosities for the four binary liquid mixtures of methyl acrylate, ethyl acrylate, butyl acrylate and methyl methacrylate with hexane-1-ol at temperatures 303.15 and 313.15 K and at atmospheric pressure were measured over the entire composition range. These values were used to calculate excess molar volumes and deviation in viscosities which were fitted to Redlich–Kister polynomial equation. Recently proposed Jouyban Acree model was also used to correlate the experimental value...

Zeolites adsorbent study containing zinc for remove gasoline in 2-propanothiol/hexane mixture; Estudo de adsorventes zeoliticos contendo zinco, para remocao de enxofre na mistura 2-propanotiol/hexano

Energy Technology Data Exchange (ETDEWEB)

Clericuzi, G.Z.; Barbosa, C. Maria B.M. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Engenharia Quimica]. E-mail: clericuzi@bol.com.br; celmy@ufpe.br; Souza-Aguiar, E.F. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas]. E-mail: falabella@cenpes.petrobras.com.br; Medina, N. [Administracion Nacional de Combustibles Alcohol Y Portland (ANCAP) (Uruguay)]. E-mail: nildamedina@hotmail.com

2003-07-01

The control of emission sulfur of gasoline has been increasing all over the world. An important process for that reduction is certainly the hydrotreatment of the gasoline of FCC. Aiming to get lower the level of emission of the control taxes of the sulfur, an alternative process is an adsorption, using zeolites, for having less severe and more economical of operation conditions, detaching the synthetic zeolites. In the present work were used two adsorbents zeolites containing respectively 0,5% of Zinc/NaY (Zn1) and 5% of Zinc/NaY (Zn2), prepared after all was molded pellets by ionic change and using graphite to for in all, it was obtained pellets with 3 mm. The kinetic study was accomplished with a mixture of 2-propanothiol and hexane. Begging of an initial concentration of 200 mg L{sup -1} of sulfur, the results were obtained by analyses of the concentration in a chromatograph type CG and evidenced that the adsorption is more effective for Zn2 adsorbent, because of the competition among substances, solvents, hexane, and solute of 2-propanothiol, due their the molecular structures and the inferior zinc tenor than the other adsorbent. (author)

Synthesis of nanostructured catalysts based on Mn oxide for n-hexane elimination

International Nuclear Information System (INIS)

Picasso, Gino; Salazar, Ivonne; Lopez, Alcides

2011-01-01

Nanostructured Mn oxide based catalysts were synthesized by sol-gel method and corresponding bulk samples were prepared by precipitation procedure. In addition, some nanostructured samples based on Mn oxide supported on bentonite (montmorillonite) were prepared by incipient impregnation. Prior to calcination, the system was submitted by TEM analysis in order to study the peptization effect of acetic acid. The micrographs revealed that the sample prepared from nitrate precursor (0,06 M) achieved the highest monodispersion. After calcination of nanoparticles, TEM analysis has been performed in order to evaluate how extent the peptization agent is able to disperse. TEM micrographs of samples prepared from nitrate precursor revealed that the peptization effect increased with the concentration of acetic acid. XRD difractograms of Mn oxide samples showed characteristic well-defined diffraction peaks associated to Mn species as Mn 2 O 3 , Mn 3 O 4 and MnO 2 with more relative intensive signals in Mn 2 O 3 and Mn 3 O 4 spinel. Finally, synthesized manganese oxide nanoparticles were incorpored into layered structure of purified bentonite (montmorillonite) by incipient impregnation. Some essays with the unsupported and supported samples were performed for n-hexane combustion in a fixed bed reactor. Activity of bentonite supported sample was lower than its unsupported bulk sample counterpart; however the performance was higher than the corresponding to the support without active component probably due to more suitable structure position of nanoparticles into layered framework of starting bentonite. (author).

Arrabidaea chica Hexanic Extract Induces Mitochondrion Damage and Peptidase Inhibition on Leishmania spp.

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Igor A. Rodrigues

2014-01-01

Full Text Available Currently available leishmaniasis treatments are limited due to severe side effects. Arrabidaea chica is a medicinal plant used in Brazil against several diseases. In this study, we investigated the effects of 5 fractions obtained from the crude hexanic extract of A. chica against Leishmania amazonensis and L. infantum, as well as on the interaction of these parasites with host cells. Promastigotes were treated with several concentrations of the fractions obtained from A. chica for determination of their minimum inhibitory concentration (MIC. In addition, the effect of the most active fraction (B2 on parasite’s ultrastructure was analyzed by transmission electron microscopy. To evaluate the inhibitory activity of B2 fraction on Leishmania peptidases, parasites lysates were treated with the inhibitory and subinhibitory concentrations of the B2 fraction. The minimum inhibitory concentration of B2 fraction was 37.2 and 18.6 μg/mL for L. amazonensis and L. infantum, respectively. Important ultrastructural alterations as mitochondrial swelling with loss of matrix content and the presence of vesicles inside this organelle were observed in treated parasites. Moreover, B2 fraction was able to completely inhibit the peptidase activity of promastigotes at pH 5.5. The results presented here further support the use of A. chica as an interesting source of antileishmanial agents.

Changes of refractive indices in ternary mixtures containing chlorobenzene + n-hexane + (n-heptane or n-octane at 298.15 K

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M. IGLESIAS

2004-06-01

Full Text Available The refractive indices of ternary mixtures of chlorobenzene + n-hexane + (n-heptane or n-octane have been measured at 298.15 K and at atmospheric pressure over the whole composition diagram. Parameters of polynomial equations which represent the composition dependence of physical and derived properties are gathered. The experimental refractive indices and the ternary derived properties are compared with the data obtained using several predictive semi-empirical models. The use of the Soave–Redlich–Kwong (SRK and the Peng–Robinson (PR cubic equations of state with the Van der Waals one-fluid mixing rule, which incorporate different combining rules to predict refractive indices on mixing, are tested against the measured results, good agrement being obtained.

The n-hexane and chloroform fractions of Piper betle L. trigger different arms of immune responses in BALB/c mice and exhibit antifilarial activity against human lymphatic filarid Brugia malayi.

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Singh, Meghna; Shakya, Shilpy; Soni, Vishal Kumar; Dangi, Anil; Kumar, Nikhil; Bhattacharya, Shailja-Misra

2009-06-01

Modulation of immune functions by using herbal plants and their products has become fundamental regime of therapeutic approach. Piper betle Linn. (Piperaceae) is a widely distributed plant in the tropical and subtropical regions of the world and has been attributed as traditional herbal remedy for many diseases. We have recently reported the antifilarial and antileishmanial efficacy in the leaf extract of Bangla Mahoba landrace of P. betle which is a female plant. The present report describes the in vivo immunomodulatory efficacy of the crude methanolic extract and its n-hexane, chloroform, n-butanol fractions of the female plant at various dose levels ranging between 0.3 and 500 mg/kg in BALB/c. Attempts were also made to observe antifilarial activity of the active extracts and correlate it with the antigen specific immune responses in another rodent Mastomys coucha infected with human lymphatic filarial parasite Brugia malayi. The crude methanol extract and n-hexane fraction were found to potentiate significant (p<0.001) enhancement of both humoral (plaque forming cells, hemagglutination titre) as well as cell-mediated (lymphoproliferation, macrophage activation, delayed type hypersensitivity) immune responses in mice. The flow cytometric analysis of splenocytes of treated mice indicated enhanced population of T-cells (CD4(+), CD8(+)) and B-cells (CD19(+)). The n-hexane fraction (3 mg/kg) was found to induce biased type 2 cytokine response as revealed by increased IL-4(+) and decreased IFN-gamma(+) T-cell population while the chloroform fraction (10 mg/kg) produced a predominant type 1 cytokines. Crude methanolic extract (100 mg/kg) demonstrated a mixed type 1 and type 2 cytokine responses thus suggesting a remarkable immunomodulatory property in this plant. The induction of differential T-helper cell immune response appears ideal to overcome immunosuppression as observed in case of lymphatic, filarial Brugia malayi infection which may also be extended to other

Crystal structure of mer-tris{2,6-difluoro-3-[5-(2-fluorophenylpyridin-2-yl-κN]pyridin-4-yl-κC4}iridium(III dichloromethane hemisolvate n-hexane hemisolvate

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Youngjin Kang

2017-12-01

Full Text Available The asymmetric unit of the title compound, [Ir(C17H11F2N23]·0.5CH3(CH24CH3·0.5CH2Cl2, comprises one IrIII atom, three 2,6-difluoro-3-[5-(2-fluorophenylpyridin-2-yl]pyridin-4-yl ligands and half each of an n-hexane and a dichloromethane solvent molecule located about crystallographic inversion centres. The IrIII atom displays a distorted octahedral coordination geometry, having three C,N-chelating 2,6-difluoro-3-[5-(2-fluorophenylpyridin-2-yl]pyridin-4-yl ligands arranged in a meridional manner. The IrIII ion lies almost in the equatorial plane [deviation = 0.0069 (15 Å]. The average distance [2.041 (3 Å] of Ir—C bonds is slightly shorter than that [2.076 (3 Å] of Ir—N bonds. A variety of intra- and intermolecular C—H...F and C—H...π hydrogen bonds, as well as intermolecular C—F...π interactions, contribute to the stabilization of the molecular and crystal structures, and result in the formation of a two-dimensional network parallel to the ab plane. No interactions between n-hexane solvent molecules and the other components in the title compound are observed.

A comparative study on composition and antioxidant activities of supercritical carbon dioxide, hexane and ethanol extracts from blackberry (Rubus fruticosus) growing in Poland.

Science.gov (United States)

Wajs-Bonikowska, Anna; Stobiecka, Agnieszka; Bonikowski, Radosław; Krajewska, Agnieszka; Sikora, Magdalena; Kula, Józef

2017-08-01

Large quantities of blackberry seeds are produced as a pomace during the processing of juice and jam production; this by-product is a very interesting raw material both for oil manufacturing and as a source of bioactive compounds. In this work the composition, yield and antioxidant activity of three types of Rubus fructicosus pomace extracts isolated by liquid extraction using solvents of different polarity, as well with supercritical CO 2 fluid extraction have been compared. The highest extract yield was reported for Soxhlet extraction using ethanol as a solvent (14.2%). Supercritical carbon dioxide and hexane extracts were characterised by the highest content of phytosterols (1445 and 1583 mg 100 g -1 of extract, respectively) among which β-sitosterol was the main one, while the concentration of tocopherols, with predominant γ-isomer, was the highest for both hexane and ethanol extracts, being 2364 and 2334 mg 100 g -1 , respectively. Using a GC-MS method 95 volatiles, in which non-saturated aldehydes were predominant, were identified in the essential oil of seed pomace and in the volatile oil isolated from supercritical extract. The ethanolic extract which is characterised by the highest phenolic content (9443 mg GAE 100 g -1 ) exhibited the highest antioxidant activity (according to the ABTS •+ and DPPH • assays). All pomace extracts examined were of high quality, rich in essential omega fatty acids and with a very high content of bioactive compounds, such as phytosterols and tocopherols. The high nutritional value of extracts from berry seed pomace could justify the commercialisation of specific extracts not only as food additives but also as cosmetic components. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Nanosized catalysts based on Fe oxide for combustion of n-hexane

International Nuclear Information System (INIS)

Picasso, Gino; Hermoza, Emilia; Lopez, Alcides; Gomez, Gemma; Pina, Maria Pilar; Herguido, Javier

2009-01-01

In this work, nanosized catalysts on Fe oxide have been prepared for total combustion on n-hexane (2000 ppmV). The synthesis of Fe oxide have been performed following sol-gel procedure starting from precursors based on nitrate salts. According to XRD analysis, nanoparticles formed α-hematite and the average particle size estimated by TEM was 9 nm with formation of agglomerations of 140 nm. Moreover, different clays pillared with Al (Al-PILC), Ti (Ti-PILC) and Fe (Fe-PILC) have been synthesized. Some samples based on Fe-Mn equimolar mixed supported on Al-PILC (FeMn/Al-PILC) and on Ti-PILC (FeMn/Ti-PILC) have been prepared in order to study the cooperative effect of Mn. Experimental conditions of calcination were adjusted in order to obtain samples with high thermal stability. XRD analysis of pillared samples revealed the formation of stable pillars, except for Fe-PILC which described a delaminated structure. As a consequence of pillaring, an enhancement of total surface area compared to starting clay material is observed. Concerning surface area, the decreasing order series of pillared material was: Ti-PILC > Fe-PILC > Al-PILC. Depression of total surface area decreasing of basal spacing d 001 with no modification of basal structure of starting natural clay have been observed due to the incorporation of Fe-Mn active phase into the structures of Ti-PILC and Al-PILC. The Fe-Mn mixed phase supported over pillared material exhibited higher catalytic activity than the Fe-PILC sample, which was attributed to the cooperative effect of Mn. This effect could be associated with redox properties of Mn and improving of surface oxygen mobility. Delaminated structure and strong interaction of Fe with clay porous network into the Fe-PILC sample could be the reason of lower activities. However, higher performances were observed in the case of Fe oxide nanoparticles prepared with surfactant agent over bentonite, due to a lesser extent of Fe-porous structure interaction presented in

Catalytic oxidation of n-hexane promoted by Ce{sub 1−x}Cu{sub x}O{sub 2} catalysts prepared by one-step polymeric precursor method

Energy Technology Data Exchange (ETDEWEB)

Araújo, Vinícius D., E-mail: dantas@ursa.ifsc.usp.br [Instituto de Física, Universidade de São Paulo – USP, 13560-970 São Carlos, SP (Brazil); Lima, Maurício M. de [Instituto de Ciencia de los Materiales, Universidad de Valencia, E-46071 Valencia (Spain); Fundación General, Universitat de Valencia, Valencia (Spain); Cantarero, Andrés [Instituto de Ciencia de los Materiales, Universidad de Valencia, E-46071 Valencia (Spain); Bernardi, Maria I.B. [Instituto de Física, Universidade de São Paulo – USP, 13560-970 São Carlos, SP (Brazil); Bellido, Jorge D.A. [CAP-Engenharia Química, Universidade Federal de São João Del-Rei – UFSJ, São João Del-Rei, MG (Brazil); Assaf, Elisabete M. [Instituto de Química, Universidade de São Paulo – USP, 13560-970 São Carlos, SP (Brazil); Balzer, Rosana; Probst, Luiz F.D. [Departamento de Química, Universidade Federal de Santa Catarina – UFSC, 88040-900 Florianópolis, SC (Brazil); Fajardo, Humberto V. [Departamento de Química, Universidade Federal de Ouro Preto – UFOP, 35400-000 Ouro Preto, MG (Brazil)

2013-11-01

Ceria-supported copper catalysts (Ce{sub 1−x}Cu{sub x}O{sub 2}, with x (mol) = 0, 0.01, 0.03, 0.05 and 0.10) were prepared in one step through the polymeric precursor method. The textural properties of the catalysts were investigated by X-ray diffraction (XRD), Rietveld refinement, N{sub 2}-physisorption (BET surface area), electron paramagnetic resonance (EPR), UV–visible diffuse reflectance and photoluminescence spectroscopies and temperature-programmed reduction (TPR). In a previous study ceria-supported copper catalysts were found to be efficient in the preferential oxidation of CO. In this study, we extended the catalytic application of Ce{sub 1−x}Cu{sub x}O{sub 2} systems to n-hexane oxidation and it was verified that the catalysts were highly efficient in the proposed reaction. The best performance (up to 95% conversion) was observed for the catalysts with low copper loads (Ce{sub 0.97}Cu{sub 0.03}O{sub 2} and Ce{sub 0.99}Cu{sub 0.01}O{sub 2}, respectively). The physicochemical characterizations revealed that these behaviors could be attributed to the copper species present in the catalysts and the interaction between CuO and CeO{sub 2}, which vary according to the copper content. - Highlights: • Synthesis of CuO/CeO2 catalysts by the one-step polymeric precursor method. • 95% n-hexane conversion on Ce0.97Cu0.03O2 catalyst. • Redox properties play a key role in the catalytic performance.

Molecular mechanics and quantum mechanical modeling of hexane soot structure and interactions with pyrene

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Kubicki JD

2000-09-01

Full Text Available Molecular simulations (energy minimizations and molecular dynamics of an n-hexane soot model developed by Smith and co-workers (M. S. Akhter, A. R. Chughtai and D. M. Smith, Appl. Spectrosc., 1985, 39, 143; ref. 1 were performed. The MM+ (N. L. Allinger, J. Am. Chem. Soc., 1977, 395, 157; ref. 2 and COMPASS (H. Sun, J. Phys. Chem., 1998, 102, 7338; ref. 3 force fields were tested for their ability to produce realistic soot nanoparticle structure. The interaction of pyrene with the model soot was simulated. Quantum mechanical calculations on smaller soot fragments were carried out. Starting from an initial 2D structure, energy minimizations are not able to produce the observed layering within soot with either force field. Results of molecular dynamics simulations indicate that the COMPASS force field does a reasonably accurate job of reproducing observations of soot structure. Increasing the system size from a 683 to a 2732 atom soot model does not have a significant effect on predicted structures. Neither does the addition of water molecules surrounding the soot model. Pyrene fits within the soot structure without disrupting the interlayer spacing. Polycyclic aromatic hydrocarbons (PAH, such as pyrene, may strongly partition into soot and have slow desorption kinetics because the PAH-soot bonding is similar to soot–soot interactions. Diffusion of PAH into soot micropores may allow the PAH to be irreversibly adsorbed and sequestered so that they partition slowly back into an aqueous phase causing dis-equilibrium between soil organic matter and porewater.

Effects of intermolecular interactions on absorption intensities of the fundamental and the first, second, and third overtones of OH stretching vibrations of methanol and t-butanol‑d9 in n-hexane studied by visible/near-infrared/infrared spectroscopy

Science.gov (United States)

Morisawa, Yusuke; Suga, Arisa

2018-05-01

Visible (Vis), near-infrared (NIR) and IR spectra in the 15,600-2500 cm- 1 region were measured for methanol, methanol-d3, and t-butanol-d9 in n-hexane to investigate effects of intermolecular interaction on absorption intensities of the fundamental and the first, second, and third overtones of their OH stretching vibrations. The relative area intensities of OH stretching bands of free and hydrogen-bonded species were plotted versus the vibrational quantum number using logarithm plots (V = 1-4) for 0.5 M methanol, 0.5 M methanol‑d3, and 0.5 M t-butanol-d9 in n-hexane. In the logarithm plots the relative intensities of free species yield a linear dependence irrespective of the solutes while those of hydrogen-bonded species deviate significantly from the linearity. The observed results suggest that the modifications in dipole moment functions of the OH bond induced by the formation of the hydrogen bondings change transient dipole moment, leading to the deviations of the dependences of relative absorption intensities on the vibrational quantum number from the linearity.

First observation of alkyne radical anions by electron spin resonance spectroscopy: Hexyne/n-hexane mixed crystals

International Nuclear Information System (INIS)

Matsuura, K.; Muto, H.

1991-01-01

The radical anions of alkynes have been first observed by electron spin resonance spectroscopy following alkene anions previously studied. Hexyne radical anions were formed in 1-, 2-, or 3-hexyne/n--hexane mixed crystals irradiated at 4.2 or 77 K. The characters of the anions were as follows; (a) the α-proton hyperfine coupling is very large (∼4.5 mT for the 1-hexyne anion), (b) the β-proton couplings are very small (∼1.0 mT for C--H β proton with the conformational angle of 0 degree), and (c) the radicals show a negative g shift (2.0014). From these observations, it was found that the anions have a nonlinear(bent) molecule structure in the anticonfiguration (trans C--C≡C--C) with the bend angle ∼60 degree, and that the unpaired electron orbital is approximately composed of the anticombination of the sp 2 hybrid orbitals of the C≡C carbon atoms. A discussion based on complete neglect of differential overlap (CNDO) molecular orbital (MO) calculations was given for the observed negative g shift, which was shown to be characteristic of the alkyne anions which have a high-lying unpaired electron orbital and an antibonding 2p--2p π carbon orbital just above it on the upper energy side

Molecular exchange of n-hexane in zeolite sieves studied by diffusion-diffusion and T{sub 1}-diffusion nuclear magnetic resonance exchange spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Neudert, Oliver; Stapf, Siegfried; Mattea, Carlos, E-mail: carlos.mattea@tu-ilmenau.de [Fachgebiet Technische Physik II/Polymerphysik, Institute of Physics, Technische Universitaet Ilmenau, PO Box 100 565, 98684 Ilmenau (Germany)

2011-03-15

Molecular exchange properties and diffusion of n-hexane embedded in a bimodal pore structure with characteristic length scales in the order of nano and micrometres, respectively, formed by packing of zeolite particles, are studied. Two-dimensional (2D) nuclear magnetic resonance (NMR) diffusion correlation experiments together with relaxation-diffusion correlation experiments are performed at low magnetic field using a single-sided NMR scanner. The exchange time covers a range from 10{sup -3} to 10{sup -1} s. The molecular exchange properties are modulated by transport inside the zeolite particles. Different exchange regimes are observed for molecules starting from different positions inside the porous sample. The influence of the spin-lattice relaxation properties of the fluid molecules inside the zeolite particles on the signal intensity is also studied. A Monte Carlo simulation of the exchange process is performed and is used to support the analysis of the experimental data.

Determination of tributyltin (TBT) in marine sediment using pressurised liquid extraction-gas chromatography-isotope dilution mass spectrometry (PLE-GC-IDMS) with a hexane-tropolone mixture.

Science.gov (United States)

Konieczka, Piotr; Sejerøe-Olsen, Berit; Linsinger, Thomas P J; Schimmel, Heinz

2007-06-01

Extraction conditions for the determination of tributyltin (TBT) in sediment samples have been developed further. The analytical procedure is based on spiking with isotopically labelled analyte, pressurised liquid extraction (PLE) with a hexane/tropolone mixture, Grignard derivatization and quantification by GC-MS. It was applied to two unknown sediment samples as part of an intercomparison exercise of the Comité Consultatif pour la Quantité de Matière (CCQM). The detection limit was approximately 1.5 ng/g TBT as Sn, while the repeatability and intermediate precision (as the coefficient of variation) were 1.9% and 3.2%, respectively. The expanded uncertainty was 6.2% (coverage factor k = 2), and the accuracy was confirmed by measurement of a certified reference material.

Thermodynamic properties of donor-acceptor complexes of tertiary amine with aryl ketones in hexane medium

Energy Technology Data Exchange (ETDEWEB)

Kumar, R. [Department of Physics, The New College, Chennai 600 014 (India); Jayakumar, S. [Department of Physics, R.K.M. Vivekananda College, Chennai 600 004 (India); Kannappan, V., E-mail: vkannappan@hotmail.com [Department of Chemistry, Presidency College, Chennai 600 005 (India)

2012-05-20

Highlights: Black-Right-Pointing-Pointer Ultrasonic scan is carried out on ternary systems of aromatic tertiary amine and three aryl ketones. Black-Right-Pointing-Pointer Formation of CT complexes is found between tertiary amine with aryl ketones. Black-Right-Pointing-Pointer Stability constant values are computed by ultrasonic and spectral methods are compared. Black-Right-Pointing-Pointer The trend in the 'K' suggests that substituents in ketones influence the stabilities of these complexes. Black-Right-Pointing-Pointer The thermodynamic parameters suggest CT interaction is exothermic and the complexes are thermodynamically stable. - The thermodynamic stability of complexes formed between N,N-dimethylaniline (DMANI) and three ketones, namely, acetophenone (ACP), 4-chloroactophenone (ClACP) and 4-methylacetophenone (MACP) in n-hexane is extensively investigated by spectral and ultrasonic methods. The ultrasound scan was carried out in the temperature range 208.15-313.15 K and at atmospheric pressure on solutions containing equimolar concentrations of components ranging from 0.025 to 0.2 M. The existence of solute-solute interactions has also been confirmed through electronic absorption spectra analyzed with Benesi-Hildebrand theory at 303.15 K. The stability constants of the donor-acceptor complexes determined both by spectroscopic and ultrasonic methods are comparable and follow similar trends. The trend in the formation constants is discussed with structures of the components. The thermodynamic behavior of the systems was explained through the computed values of the free energy ({Delta}G), enthalpy ({Delta}H) and entropy ({Delta}S) changes for complex formation are computed and discussed.

Atividade antibacteriana de floroglucinóis e do extrato hexânico de Hypericum brasiliense Choysi Antibacterial activity of the phloroglucinols and hexanic extract from Hypericum brasiliense Choysi

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Hildegardo Seibert França

2009-01-01

Full Text Available Three phloroglucinols were obtained from Hypericum brasiliense: japonicine A (1, isouliginosin B (2 and uliginosin B (3. Bioautography and disk diffusion methods were used to determine antibacterial activity of the hexanic extract. Strains of the Coagulase Negative Staphylococcus and American Methicillin Resistant Staphylococcus aureus clones showed a growth inhibition zone ranging from 10 to 12 mm and 7 to 15 mm, respectively. Minimal inhibitory concentration (MIC values were used to measure antistaphylococcal activity for all phloroglucinols. Isouliginosin B and uliginosin B presented MIC values of 1.5 and 3.0 µg/mL, respectively, while japonicine A displayed MIC value of 50.0 µg/mL.

Aislamiento y caracterización de la fracción hexánica de las hojas de Vernonanthura patens (Kunth H. Rob. con actividad antifúngica Isolation and characterization of hexane fraction from Vernonanthura patens (Kunth H. Rob leaves with antifungal action

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Patricia Manzano Santana

2012-09-01

extract from the leaves was fractionated by column chromatography using the following solvent systems: hexane, hexane/ethyl acetate, ethyl acetate and ethyl acetate/methanol. Antifungal activity was measured by the agar diffusion technique with PDA medium in 5 mm wells, by adding 20 µL fractions at concentrations of 100 and 200 µg/mL dissolved in dimethylsulfoxide. The active fraction was analyzed for structural identification by gas chromatography-mass spectrometry. Results: of the fractions obtained, only the 100% hexane fraction showed antifungal activity, since its inhibitory percentages were 57.6 and 80.2 % against Penicillium notatum and 64.8 and 81.5 % vs. Fusaryum oxysporum on the fifteenth day of incubation. The structures of 29 compounds were suggested to be the constituents of the hexane fraction, most of them hydrocarbons. Conclusions: the presence of antifungal activity in the 100 % hexane fraction was proved, which can extend the medicinal uses of the studied plant and to enrich the Ecuadorian folk medicine.

Development of a Henry's constant correlation and solubility measurements of n-pentane, i-pentane, cyclopentane, n-hexane, and toluene in water

International Nuclear Information System (INIS)

Chapoy, Antonin; Haghighi, Hooman; Tohidi, Bahman

2008-01-01

In this communication, we report new experimental data on n-pentane, i-pentane, cyclopentane, n-hexane, and toluene solubility in water at low temperature (below 298.15 K) and atmospheric pressure conditions. The new experimental data together with those reported in the literature have been used in developing a new equation for Henry's constants of normal alkanes (methane to decane), BETEX compounds, and acid gases in aqueous phase over a wide range of temperature (typically from 273.15 K to 373.15 K). The new equation is based on a thermodynamic model, which uses the Peng-Robinson equation of state combined with the classical quadratic mixing rules for modelling non-aqueous phases, while the NRTL model is used to calculate the water activity. The predictions of the developed thermodynamic model are compared to the experimental data and the results of a thermodynamic approach, which uses the Valderrama modification of the Patel-Teja equation of state and non-density dependent mixing rules for modelling all fluid phases. Good agreement is observed between the experimental data and the model predictions

The long chain of the n-hexane fraction of water hyacinth (eichhornia crassipes): extrction, estimation, GC-MS analysis and antimicrobial activity

International Nuclear Information System (INIS)

Hussain, Z.; Khan, K.M.

2015-01-01

Oily fraction was extracted from the water hyacinth (Eichhornia crassipes) using n-hexane by both cold and hot extraction in 5.5 ± 0.05% and 9.30 ± 0.05%, respectively, however, no difference was found in the nature of the compounds extracted by the two processes. The analysis of this oil was carried out using GC-FID and GC-MS in separate experiments and the nature of the compounds was investigated by library matching of the spectra obtained through GC-MS. This extract was found to contain 33.267% of the nonadecan-4-ol and 20.51% of a long chain ketone in addition to various quantities of the long chain nitrogenous compounds. The antibacterial activity of the extract was investigated against eight pathogenic bacteria and fungus Candida albican using disc diffusion method. The extract was found to be highly active against all tested bacterial strains except S. typhi. For most of the strains the activity of the extract was near the reference. Ciprofloxacin, clotrimazole and erythromycin were used as reference antibiotics. (author)

A Limited Role of p53 on the Ability of a Hexane Fraction of American Ginseng to Suppress Mouse Colitis

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Deepak Poudyal

2012-01-01

Full Text Available Ulcerative colitis (UC is debilitating and carries a high colon cancer risk. Apoptosis of inflammatory cells is a key mechanism regulating UC. We have recently shown that American ginseng (AG, and to a greater extent, a Hexane fraction of AG (HAG can cause apoptosis and suppress mouse colitis through a p53-mediated mechanism. Here, we tested the hypothesis that HAG suppresses colitis through a p53 mechanism. We found only a limited impact of p53 in the ability of HAG to induce inflammatory cell apoptosis and suppress mouse colitis in vitro and in vivo. Finally, we asked whether HAG could cause cell cycle arrest of HCT116 colon cancer cells in vitro. Interestingly, HAG caused a G1 arrest of such cells independent of p53 status. Findings are significant because HAG suppresses colitis and associated colon cancer, and mutation in p53 is observed in most colitis-driven colon cancers. Therefore, HAG might be very effective in targeting the inflammatory cells and cancer cells since it induces apoptosis of inflammatory cells and cell cycle arrest in both p53−/− and WT p53 colon cancer cells.

高压下甲烷在乙醇-正己烷混合溶剂中的溶解度测定与研究%Solubility of Methane in the Mixture of Ethanol+Hexane at High Pressures

Institute of Scientific and Technical Information of China (English)

华超; 马沛生; 夏淑倩; 白鹏

2005-01-01

Solubility data were first presented for methane in the mixture of ethanol-hexane at temperatures from 291.15 K to 318.15K and pressures up to 12.00MPa. The experimental data were correlated by PR and PRSV equations of state with rms errors of about 0.051. The A-K and Y-W-A-K models were both used to estimate liquid molar volume under high pressure. The results were satisfactory.

Study of the binary mixtures of {monoglyme + (hexane, cyclohexane, octane, dodecane)} by ECM-average and PFP models

International Nuclear Information System (INIS)

Rivas, M.A.; Buep, A.H.; Iglesias, T.P.

2015-01-01

Highlights: • Polarization of the real mixture is less than that of the ideal mixture. • Molar excess volume does not exert the dominant effect on the polarization of the mixture. • Similar influence of molecular interactions on the behaviour of excess permittivity. • Excess molar volume is more influenced by the interactions than excess permittivity. - Abstract: Excess molar volumes and excess permittivity of binary mixtures involving monoglyme and alkanes, such as n-hexane, cyclohexane, n-octane and n-dodecane, were calculated from density and relative permittivity measurements for the entire composition range at several temperatures (288.15, 298.15 and 308.15) K and atmospheric pressure. The excess permittivity was calculated on the basis of a recent definition considering the ideal volume fraction. Empirical equations for describing the experimental data in terms of temperature and concentration are given. The experimental values of permittivity have been compared with those estimated by well-known models from literature. The results have indicated that better predictions are obtained when the volume change on mixing is incorporated in these calculations. The contribution of interactions to the excess permittivity was analysed by means of the ECM-average model. The Prigogine–Flory–Patterson (PFP) theory of the thermodynamics of solutions was used to shed light on the contribution of interactions to the excess molar volume. The work concludes with an interpretation of the information given by the theoretical models and the behaviour of both excess magnitudes

(1R,2R,3R,4R,5S-2,3-Bis[(2S′-2-acetoxy-2-phenylacetoxy]-4-azido-1-[(2,4-dinitrophenylhydrazonomethyl]bicyclo[3.1.0]hexane

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Robert McDonald

2008-02-01

Full Text Available In the title compound, C38H29N7O12, the five-membered ring adopts an envelope conformation in which the `flap' is cis to the cyclopropane group. This conformation is similar to those of other bicyclo[3.1.0]hexane analogues for which crystal structures have been reported. The absolute configuration of the stereogenic centers on the cyclopentane ring, as determined by comparison with the known configurations of the stereogenic centers in the (2S-2-acetoxy-2-phenylacetoxy groups, is 1(R, 2(R, 3(R, 4(R and 5(S. An intramolecular N—H...O hydrogen bond is present.

High-temperature catalytic reforming of n-hexane over supported and core-shell Pt nanoparticle catalysts: role of oxide-metal interface and thermal stability.

Science.gov (United States)

An, Kwangjin; Zhang, Qiao; Alayoglu, Selim; Musselwhite, Nathan; Shin, Jae-Youn; Somorjai, Gabor A

2014-08-13

Designing catalysts with high thermal stability and resistance to deactivation while simultaneously maintaining their catalytic activity and selectivity is of key importance in high-temperature reforming reactions. We prepared Pt nanoparticle catalysts supported on either mesoporous SiO2 or TiO2. Sandwich-type Pt core@shell catalysts (SiO2@Pt@SiO2 and SiO2@Pt@TiO2) were also synthesized from Pt nanoparticles deposited on SiO2 spheres, which were encapsulated by either mesoporous SiO2 or TiO2 shells. n-Hexane reforming was carried out over these four catalysts at 240-500 °C with a hexane/H2 ratio of 1:5 to investigate thermal stability and the role of the support. For the production of high-octane gasoline, branched C6 isomers are more highly desired than other cyclic, aromatic, and cracking products. Over Pt/TiO2 catalyst, production of 2-methylpentane and 3-methylpentane via isomerization was increased selectively up to 420 °C by charge transfer at Pt-TiO2 interfaces, as compared to Pt/SiO2. When thermal stability was compared between supported catalysts and sandwich-type core@shell catalysts, the Pt/SiO2 catalyst suffered sintering above 400 °C, whereas the SiO2@Pt@SiO2 catalyst preserved the Pt nanoparticle size and shape up to 500 °C. The SiO2@Pt@TiO2 catalyst led to Pt nanoparticle sintering due to incomplete protection of the TiO2 shells during the reaction at 500 °C. Interestingly, over the Pt/TiO2 catalyst, the average size of Pt nanoparticles was maintained even after 500 °C without sintering. In situ ambient pressure X-ray photoelectron spectroscopy demonstrated that the Pt/TiO2 catalyst did not exhibit TiO2 overgrowth on the Pt surface or deactivation by Pt sintering up to 600 °C. The extraordinarily high stability of the Pt/TiO2 catalyst promoted high reaction rates (2.0 μmol · g(-1) · s(-1)), which was 8 times greater than other catalysts and high isomer selectivity (53.0% of C6 isomers at 440 °C). By the strong metal-support interaction

Acute toxicity of toluene, hexane, xylene, and benzene to the rotifers Brachionus calyciflorus and Brachionus plicatilis

Energy Technology Data Exchange (ETDEWEB)

Ferrando, M.D.; Andreu-Moliner, E. (Univ. of Valencia (Spain))

1992-08-01

A large number of studies on the biological effects of oil pollution in the aquatic environment deal with the effects of whole crude or refined oils or their water-soluble fractions. However, low boiling, aromatic hydrocarbons, which are probably the most toxic constituents of oil, have until now not been examined in sufficient detail. Toluene, benzene and xylene, constitute a major component of various oils. They may be readily lost by weathering but are toxic in waters that are relatively stagnant and are chronically polluted. Korn et al. have stated that toluene is more toxic than many other hydrocarbons such as benzene, though the latter are more water-soluble. Report of the effects of exposure to organic solvents like hexane or toluene are still limited although organic solvents are a well-known group of neurointoxicants. Various benzene derivates continue to be used as chemical intermediates, solvents, pesticides, so on, in spite of incomplete knowledge of their chronic toxicity. The majority of toxicity studies about the effects of pollution on aquatic organisms under controlled conditions have used either fish or the cladoceran Daphnia magna and there are few studies reported using rotifers. The effects of herbicides on population variables of laboratory rotifer cultures have been investigated. Rotifers are one of the main sources of zooplankton production and they have an important ecological significance in the aquatic environment. The present work was designed to investigate the effect of short-term exposure to some petroleum derivates which might be expected to occur immediately under an oil-slick, on freshwater and brackish environment rotifers. 18 refs., 1 tab.

Vapor phase nucleation of the short-chain n-alkanes (n-pentane, n-hexane and n-heptane): Experiments and Monte Carlo simulations

Science.gov (United States)

Ogunronbi, Kehinde E.; Sepehri, Aliasghar; Chen, Bin; Wyslouzil, Barbara E.

2018-04-01

We measured the nucleation rates of n-pentane through n-heptane in a supersonic nozzle at temperatures ranging from ca. 109 K to 168 K. For n-pentane and n-hexane, these are the first nucleation rate measurements that have been made, and the trends in the current data agree well with those in the earlier work of Ghosh et al. [J. Chem. Phys. 132, 024307 (2010)] for longer chain alkanes. Complementary Monte Carlo simulations, using the transferable potentials for phase equilibria-united atom potentials, suggest that despite the high degree of supercooling, the critical clusters remain liquid like under experimental conditions for n-pentane through n-heptane, but adopt more ordered structures for n-octane and n-nonane. For all three alkanes, the experimental and simulated nucleation rates are offset by ˜3 orders of magnitude when plotted as a function of ln S/(Tc/T - 1)1.5. Explicitly accounting for the surface tension difference between the real and model substances, or alternatively using the Hale [Phys. Rev. A 33, 4156 (1986); Metall. Mater. Trans. A 23, 1863 (1992)] scaling parameter, Ω, consistent with the model potential, increases the offset to ˜6 orders of magnitude.

A case report of motor neuron disease in a patient showing significant level of DDTs, HCHs and organophosphate metabolites in hair as well as levels of hexane and toluene in blood

International Nuclear Information System (INIS)

Kanavouras, Konstantinos; Tzatzarakis, Manolis N.; Mastorodemos, Vasileios; Plaitakis, Andreas; Tsatsakis, Aristidis M.

2011-01-01

Motor neuron disease is a devastating neurodegenerative condition, with the majority of sporadic, non-familial cases being of unknown etiology. Several epidemiological studies have suggested that occupational exposure to chemicals may be associated with disease pathogenesis. We report the case of a patient developing progressive motor neuron disease, who was chronically exposed to pesticides and organic solvents. The patient presented with leg spasticity and developed gradually clinical signs suggestive of amyotrophic lateral sclerosis, which was supported by the neurophysiologic and radiological findings. Our report is an evidence based case of combined exposure to organochlorine (DDTs), organophosphate pesticides (OPs) and organic solvents as confirmed by laboratory analysis in samples of blood and hair confirming systematic exposure. The concentration of non-specific dialkylphosphates metabolites (DAPs) of OPs in hair (dimethyphopshate (DMP) 1289.4 pg/mg and diethylphosphate (DEP) 709.4 pg/mg) and of DDTs (opDDE 484.0 pg/mg, ppDDE 526.6 pg/mg, opDDD 448.4 pg/mg, ppDDD + opDDT 259.9 pg/mg and ppDDT 573.7 pg/mg) were considerably significant. Toluene and n-hexane were also detected in blood on admission at hospital and quantified (1.23 and 0.87 μg/l, respectively), while 3 months after hospitalization blood testing was found negative for toluene and n-hexane and hair analysis was provided decrease levels of HCHs, DDTs and DAPs. -- Highlights: ► Exposure to pesticides and organic solvents might be a risk factor for sporadic MND. ► We report a patient who developed progressive upper and lower motor neuron disease. ► The patient had a history of occupational exposure to pesticides and solvents. ► High DDTs’ levels and increased levels of DMP and DEP were measured in his hair. ► The patients’ exposure to chemicals might have played a role in MND development.

Hexane extracts of Polygonum multiflorum improve tissue and functional outcome following focal cerebral ischemia in mice.

Science.gov (United States)

Lee, Soo Vin; Choi, Kyung Ha; Choi, Young Whan; Hong, Jin Woo; Baek, Jin Ung; Choi, Byung Tae; Shin, Hwa Kyoung

2014-04-01

Polygonum multiflorum is a traditional Korean medicine that has been utilized widely in East Asian countries as a longevity agent. Clinical studies have demonstrated that Polygonum multiflorum improves hypercholesterolemia, coronary heart disease, neurosis and other diseases commonly associated with aging. However, scientific evidence defining the protective effects and mechanisms of Polygonum multiflorum against ischemic stroke is incomplete. In the present study, we investigated the cerebrovascular protective effects of Polygonum multiflorum against ischemic brain injury using an in vivo photothrombotic mouse model. To examine the underlying mechanism of action, we utilized an in vitro human brain microvascular endothelial cell (HBMEC) culture system. Hexane extracts (HEPM), ethyl acetate extracts (EAEPM) and methanol extracts (MEPM) of Polygonum multiflorum (100 mg/kg) were administered intraperitoneally 30 min prior to ischemic insult. Focal cerebral ischemia was induced in C57BL/6J mice and endothelial nitric oxide synthase knockout (eNOS KO) mice by photothrombotic cortical occlusion. We evaluated the infarct volume, as well as neurological and motor function, 24 h after ischemic brain injury. Following ischemic insult, HEPM induced a significant reduction in infarct volume and subsequent neurological deficits, compared with EAEPM and MEPM. HEPM significantly decreased infarct size and improved neurological and motor function, which was not observed in eNOS KO mice, suggesting that this cerebroprotective effect is primarily an eNOS-dependent mechanism. In vitro, HEPM effectively promoted NO production, however these effects were inhibited by the NOS inhibitor, L-NAME and the PI3K/Akt inhibitor, LY-294002. Furthermore, HEPM treatment resulted in increased phosphorylation-dependent activation of Akt and eNOS in HBMEC, suggesting that HEPM increased NO production via phosphorylation-dependent activation of Akt and eNOS. In conclusion, HEPM prevents cerebral

Chemical composition of the essential oil and hexanic fraction of Lippia and Lantana species Composição química do óleo essencial e fração hexânica de espécies de Lippia e Lantana

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Pâmela S. Silva

2010-12-01

Full Text Available A comparison between two extraction approaches of volatiles compounds from six species of Verbenaceae collected at Serra do Cipó, Minas Gerais, Brazil was done. The essential oil and hexanic fraction of leaves from two Lantana and four Lippia species collected in two different seasons were analyzed by GC/MS. Among various identified compounds from both extraction methods the majority of species showed major amounts of β-caryophyllene followed by germacrene D, bicyclogermacrene and α-pinene. Few differences were observed between the composition of essential oil and the hexanic fraction regarding the two studied genera. These results suggest that the analysis of hexanic fraction can be used, as an alternative way, to analyze the volatile compounds of the essential oil.Foi realizada a comparação entre dois métodos de extração dos compostos voláteis obtidos de seis espécies de Verbenaceae, coletadas na Serra do Cipó, Minas Gerais, Brasil. Os óleos essenciais e as frações hexanica obtidos das folhas de duas espécies de Lantana e quatro espécies de Lippia, coletadas em duas diferentes estações do ano, foram analisados por CG/EM. Grande número de constituintes foi identificado nas amostras oriundas dos dois métodos de extração e o componente majoritário para a maior parte das espécies foi o β-cariofileno, seguido pelo germacreno D, biciclogermacreno e α-pineno. Para os dois gêneros estudados, foram observadas pequenas diferenças na composição do óleo essencial e fração hexânica. Esses resultados sugerem que a análise da fração hexânica pode ser usada para identificar os componentes voláteis majoritários dessas espécies, além de ser uma técnica alternativa para a análise dos compostos voláteis presentes no óleo essencial, uma vez que ambos mostraram composição similar.

Effects of high-pressure process on kinetics of leaching oil from soybean powder using hexane in batch systems.

Science.gov (United States)

Uhm, Joo Tae; Yoon, Won Byong

2011-08-01

Mass transfer models of leaching oil from soybean (Glycine max) flour with hexane after high-pressure process (HPP) treatment were developed. High pressure (450 MPa) was applied to the soybean flour (mean diameter of flour particle: 365 μm) for 30 min before leaching the oil components in the solvent. The ratio of solvent (volume, mL) to soybean flour (mass, g), such as 1:10 and 1:20, was employed to characterize the effect of solvent ratio on the leaching rate in the batch type of extraction process. Ultraviolet absorbance at 300 nm was used to monitor the extraction rate. Saturation solubility (C(AS)) was determined to be 21.73 kg/m³. The mass transfer coefficients (k) were determined based on the 1st- and 2nd-order kinetic models. The 2nd kinetic model showed better fit. The HPP treatment showed a higher extraction rate and yield compared to the control, while the amount of solvent did not affect the extraction rate and yield. The scanning electron microscope showed that HPP-treated soybean particles included more pores than the untreated. The pores observed in the HPP-treated soybean flours might help increase the mass transfer rate of solvent and solute in the solid matrix. High-pressure processing can help increase the extraction rate of oil from the soybean flour operated in batch systems. The conventional solid to solvent ratio (1:20) used to extract oil composition from the plant seed did not help increase the amount of oil extracted from the soybean flour. © 2011 Institute of Food Technologists®

n-hexane, why is a separate guideline being developed and why is it being considered for oil and gas impacted sites?

Energy Technology Data Exchange (ETDEWEB)

Knafla, A.L.; Carey, J.; Ranganathan, S. [Equilibrium Environmental Inc., Calgary, AB (Canada)

2008-07-01

Benzene, toluene, ethylbenzene, and xylenes (BTEX) compounds are among the volatile organic compounds (VOCs) found in petroleum derivatives such as gasoline and are notorious due to the contamination of soil and groundwater with these compounds. This presentation provided an overview of the F1 fraction and discussed F1 fraction toxicity. It discussed what drives the risk and why one of these compounds is being considered for removal from the mixture (such as BTEX). The focus of the presentation was on the inhalation route of exposure. Environmental data for F1 was presented with particular reference to unweathered product in terms of the mass percentage of F1 aliphatic vapours in breathing zone of gasoline station workers; and for weathered product in terms of soil vapour concentrations; and in upstream oil and gas condensate sites. Toxicity data for F1 aromatics and an exploration of commercial n-hexane (HX) toxicity were also presented. It was concluded that HX was a significant component of the F1 fraction; HX had a unique toxicity due to its mechanism of action; toxicity occurred in the presence of other F1 hydrocarbons; HX should not be used as a surrogate for F1 and should be separated and included with BTEX; HX could be detected as part of a F1; and some toxicity limit should be selected to represent HX. tabs., figs.

A case report of motor neuron disease in a patient showing significant level of DDTs, HCHs and organophosphate metabolites in hair as well as levels of hexane and toluene in blood

Energy Technology Data Exchange (ETDEWEB)

Kanavouras, Konstantinos [Department of Neurology, Medical School, University of Crete, Heraklion, Crete (Greece); Tzatzarakis, Manolis N. [Center of Toxicology Science and Research, University of Crete, Heraklion, Crete (Greece); Mastorodemos, Vasileios; Plaitakis, Andreas [Department of Neurology, Medical School, University of Crete, Heraklion, Crete (Greece); Tsatsakis, Aristidis M., E-mail: aris@med.uoc.gr [Center of Toxicology Science and Research, University of Crete, Heraklion, Crete (Greece)

2011-11-15

Motor neuron disease is a devastating neurodegenerative condition, with the majority of sporadic, non-familial cases being of unknown etiology. Several epidemiological studies have suggested that occupational exposure to chemicals may be associated with disease pathogenesis. We report the case of a patient developing progressive motor neuron disease, who was chronically exposed to pesticides and organic solvents. The patient presented with leg spasticity and developed gradually clinical signs suggestive of amyotrophic lateral sclerosis, which was supported by the neurophysiologic and radiological findings. Our report is an evidence based case of combined exposure to organochlorine (DDTs), organophosphate pesticides (OPs) and organic solvents as confirmed by laboratory analysis in samples of blood and hair confirming systematic exposure. The concentration of non-specific dialkylphosphates metabolites (DAPs) of OPs in hair (dimethyphopshate (DMP) 1289.4 pg/mg and diethylphosphate (DEP) 709.4 pg/mg) and of DDTs (opDDE 484.0 pg/mg, ppDDE 526.6 pg/mg, opDDD 448.4 pg/mg, ppDDD + opDDT 259.9 pg/mg and ppDDT 573.7 pg/mg) were considerably significant. Toluene and n-hexane were also detected in blood on admission at hospital and quantified (1.23 and 0.87 {mu}g/l, respectively), while 3 months after hospitalization blood testing was found negative for toluene and n-hexane and hair analysis was provided decrease levels of HCHs, DDTs and DAPs. -- Highlights: Black-Right-Pointing-Pointer Exposure to pesticides and organic solvents might be a risk factor for sporadic MND. Black-Right-Pointing-Pointer We report a patient who developed progressive upper and lower motor neuron disease. Black-Right-Pointing-Pointer The patient had a history of occupational exposure to pesticides and solvents. Black-Right-Pointing-Pointer High DDTs' levels and increased levels of DMP and DEP were measured in his hair. Black-Right-Pointing-Pointer The patients' exposure to chemicals might

CGAR E CGAR-EM na análise dos constituintes químicos isolados do extrato hexanico de Sebastiania argutidens (Euphorbiaceae HRGC and HRGC-MS in the analysis of the chemical constituents isolated from hexanic extract of Sebastiania argutidens (Euphorbiaceae

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Alexsandro Branco

2002-02-01

Full Text Available The fractionation column with SiO2 of the hexane extract of Sebastiania argutidens (Euphorbiaceae yielded fractions containing hydrocarbons, carboxylic acids, sterols and pentacyclic triterpenes. Besides, one fraction showed the presence of several methyl esters, including four uncommon long chain palmitate esthers as minor components. The characterization of these chemical constituents have been done by High Resolution Gas Chromatography (HRGC and HRGC coupled to Mass Spectrometry (GC/MS. Campesterol, stigmasterol, b-sitosterol, glutin-5-en-3-ol were identified by HRGC co-injection with standards.

Excess molar volumes and deviation in viscosities of binary liquid mixtures of acrylic esters with hexane-1-ol at 303.15 and 313.15 K

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Sujata S. Patil

2014-12-01

Full Text Available Densities and viscosities for the four binary liquid mixtures of methyl acrylate, ethyl acrylate, butyl acrylate and methyl methacrylate with hexane-1-ol at temperatures 303.15 and 313.15 K and at atmospheric pressure were measured over the entire composition range. These values were used to calculate excess molar volumes and deviation in viscosities which were fitted to Redlich–Kister polynomial equation. Recently proposed Jouyban Acree model was also used to correlate the experimental values of density and viscosity. The mixture viscosities were correlated by several semi-empirical approaches like Hind, Choudhary–Katti, Grunberg–Nissan, Tamura and Kurata, McAllister three and four body model equations. A graphical representation of excess molar volumes and deviation in isentropic compressibility shows positive nature whereas deviation in viscosity shows negative nature at both temperatures for all four binary liquid mixtures. Positive values of excess molar volumes show that volume expansion is taking place causing rupture of H-bonds in self associated alcohols. The results were discussed in terms of molecular interactions prevailing in the mixtures.

Beneficial Effects of Ethanolic and Hexanic Rice Bran Extract on Mitochondrial Function in PC12 Cells and the Search for Bioactive Components

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Stephanie Hagl

2015-09-01

Full Text Available Mitochondria are involved in the aging processes that ultimately lead to neurodegeneration and the development of Alzheimer’s disease (AD. A healthy lifestyle, including a diet rich in antioxidants and polyphenols, represents one strategy to protect the brain and to prevent neurodegeneration. We recently reported that a stabilized hexanic rice bran extract (RBE rich in vitamin E and polyphenols (but unsuitable for human consumption has beneficial effects on mitochondrial function in vitro and in vivo (doi:10.1016/j.phrs.2013.06.008, 10.3233/JAD-132084. To enable the use of RBE as food additive, a stabilized ethanolic extract has been produced. Here, we compare the vitamin E profiles of both extracts and their effects on mitochondrial function (ATP concentrations, mitochondrial membrane potential, mitochondrial respiration and mitochondrial biogenesis in PC12 cells. We found that vitamin E contents and the effects of both RBE on mitochondrial function were similar. Furthermore, we aimed to identify components responsible for the mitochondria-protective effects of RBE, but could not achieve a conclusive result. α-Tocotrienol and possibly also γ-tocotrienol, α-tocopherol and δ-tocopherol might be involved, but hitherto unknown components of RBE or a synergistic effect of various components might also play a role in mediating RBE’s beneficial effects on mitochondrial function.

Study of molecular interactions in binary liquid mixtures of 1-octanol with n-hexane, n-octane, and n-decane using volumetric, viscometric, and acoustic properties

International Nuclear Information System (INIS)

Dubey, Gyan P.; Sharma, Monika

2008-01-01

Experimental values of densities (ρ) and speeds of sound (u) at T = (298.15, 303.15, and 308.15) K while the viscosities (η) at T = 298.15 K in the binary mixtures of 1-octanol with n-hexane, n-octane, and n-decane are presented over the entire composition range of the binary mixtures. Using these data, excess molar volumes (V m E ), viscosity deviation (Δη), deviation in speeds of sound (Δu), deviation in isentropic compressibility (Δκ s ), excess free volume (V f E ), and excess Gibbs free energy of activation of viscous flow (ΔG* E ) are calculated and presented graphically. All the computed quantities are fitted to a polynomial equation. The values of V m E have been analyzed using Prigogine-Flory-Patterson (PFP) theory. Furthermore, the theoretical values of speed of sound (u) and isentropic compressibility (κ s ) have also been estimated using the Prigogine-Flory-Patterson (PFP) theory with the van der Waals (vdW) potential energy model and the results have been compared with experimental values. The experimental and calculated quantities are used to study the nature of mixing behaviour between the mixture components

A green approach towards adoption of chemical reaction model on 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane decomposition by differential isoconversional kinetic analysis

Energy Technology Data Exchange (ETDEWEB)

Das, Mitali; Shu, Chi-Min, E-mail: shucm@yuntech.edu.tw

2016-01-15

Highlights: • Thermally degraded DBPH products are identified. • An appropriate mathematical model was selected for decomposition study. • Differential isoconversional analysis was performed to obtain kinetic parameters. • Simulation on thermal analysis model was conducted for the best storage conditions. - Abstract: This study investigated the thermal degradation products of 2,5-dimethyl-2,5-di-(tert-butylperoxy) hexane (DBPH), by TG/GC/MS to identify runaway reaction and thermal safety parameters. It also included the determination of time to maximum rate under adiabatic conditions (TMR{sub ad}) and self-accelerating decomposition temperature obtained through Advanced Kinetics and Technology Solutions. The apparent activation energy (E{sub a}) was calculated from differential isoconversional kinetic analysis method using differential scanning calorimetry experiments. The E{sub a} value obtained by Friedman analysis is in the range of 118.0–149.0 kJ mol{sup −1}. The TMR{sub ad} was 24.0 h with an apparent onset temperature of 82.4 °C. This study has also established an efficient benchmark for a thermal hazard assessment of DBPH that can be applied to assure safer storage conditions.

Multidimensional analysis of cannabis volatile constituents: identification of 5,5-dimethyl-1-vinylbicyclo[2.1.1]hexane as a volatile marker of hashish, the resin of Cannabis sativa L.

Science.gov (United States)

Marchini, Marie; Charvoz, Céline; Dujourdy, Laurence; Baldovini, Nicolas; Filippi, Jean-Jacques

2014-11-28

The volatile constituents of drug samples derived from Cannabis sativa L. were investigated by means of headspace solid phase microextraction (HS-SPME) and gas chromatography techniques (GC-MS, GC×GC-MS). Samples of cannabis herb and hashish showed clear differences in their volatile chemical profiles, mostly resulting from photo-oxidation processes occurring during the transformation of fresh cannabis herb into hashish. Most unexpectedly, we could demonstrate hashish samples as containing remarkable amounts of a rare and unusual monoterpene - 5,5-dimethyl-1-vinylbicyclo[2.1.1]hexane - among the volatile compounds detected in their headspaces. We gave evidence for the formation of this compound from the light induced rearrangement of β-myrcene during the manufacture of hashish. In view of its high abundance among volatile constituents of cannabis resin and its scarce occurrence in other natural volatile extracts, we propose to rename this specific monoterpene hashishene. Copyright © 2014 Elsevier B.V. All rights reserved.

Catalytic oxidation of volatile organic compounds (n-hexane, benzene, toluene, o-xylene promoted by cobalt catalysts supported on γ-Al2O3-CeO2

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R. Balzer

2014-09-01

Full Text Available Cobalt catalysts supported on γ-alumina, ceria and γ-alumina-ceria, with 10 or 20%wt of cobalt load, prepared by the wet impregnation method and characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM, field emission transmission electron microscopy (FETEM, N2 adsorption-desorption isotherms (BET/BJH methods, energy-dispersive X-ray spectroscopy (EDX, X-ray photoemission spectroscopy (XPS, O2-chemisorption and temperature programmed reduction (TPR were used to promote the oxidation of volatile organic compounds (n-hexane, benzene, toluene and o-xylene. For a range of low temperatures (50-350 °C, the activity of the catalysts with a higher cobalt load (20% wt was greater than that of the catalysts with a lower cobalt load (10% wt. The Co/γ-Al2O3-CeO2 catalytic systems presented the best performances. The results obtained in the characterization suggest that the higher catalytic activity of the Co20/γ-Al2O3-CeO2 catalyst may be attributed to the higher metal content and amount of oxygen vacancies, as well as the effects of the interaction between the cobalt and the alumina and cerium oxides.

Determination of nucleic acids based on the quenching effect on resonance light scattering of the Y(III)-1,6-bi(1'-phenyl-3'-methyl-5'-pyrazolone-4'-)hexane-dione system.

Science.gov (United States)

Wu, Xia; Yang, Jing He; Sun, Shuna; Guo, Changying; Ran, Dehuan; Zheng, Jinhua

2006-01-01

Nucleic acids can quench resonance light scattering (RLS) intensity of the Y(III)-1,6-bi(1'-phenyl-3'-methyl-5'-pyrazolone-4'-)hexane-dione(BPMPHD) complex in the pH range 5.0-5.8. Under optimal conditions, there are linear relationships between the quenching of RLS and the concentration of nucleic acids in the range 6.3 x 10(-8)-2.1 x 10(-5) g/mL for fish sperm DNA (fsDNA), 1.2 x 10(-8)-5.0 x 10(-5) g/mL for calf thymus DNA (ctDNA) and 6.0 x 10(-8)-2.0 x 10(-5) g/mL for yeast RNA (yRNA). The detection limits (3 s) of fsDNA, ctDNA and yRNA are 0.7 ng/mL, 3.8 ng/mL and 4.2 ng/mL, respectively. Copyright (c) 2006 John Wiley & Sons, Ltd.

Tensiometry and dilational rheology of mixed β-lactoglobulin/ionic surfactant adsorption layers at water/air and water/hexane interfaces.

Science.gov (United States)

Dan, Abhijit; Gochev, Georgi; Miller, Reinhard

2015-07-01

Oscillating drop tensiometry was applied to study adsorbed interfacial layers at water/air and water/hexane interfaces formed from mixed solutions of β-lactoglobulin (BLG, 1 μM in 10 mM buffer, pH 7 - negative net charge) and the anionic surfactant SDS or the cationic DoTAB. The interfacial pressure Π and the dilational viscoelasticity modulus |E| of the mixed layers were measured for mixtures of varying surfactant concentrations. The double capillary technique was employed which enables exchange of the protein solution in the drop bulk by surfactant solution (sequential adsorption) or by pure buffer (washing out). The first protocol allows probing the influence of the surfactant on a pre-adsorbed protein layer thus studying the protein/surfactant interactions at the interface. The second protocol gives access to the residual values of Π and |E| measured after the washing out procedure thus bringing information about the process of protein desorption. The DoTAB/BLG complexes exhibit higher surface activity and higher resistance to desorption in comparison with those for the SDS/BLG complexes due to hydrophobization via electrostatic binding of surfactant molecules. The neutral DoTAB/BLG complexes achieve maximum elastic response of the mixed layer. Mixed BLG/surfactant layers at the water/oil interface are found to reach higher surface pressure and lower maximum dilational elasticity than those at the water/air surface. The sequential adsorption mode experiments and the desorption study reveal that binding of DoTAB to pre-adsorbed BLG globules is somehow restricted at the water/air surface in comparison with the case of complex formation in the solution bulk and subsequently adsorbed at the water/air surface. Maximum elasticity is achieved with washed out layers obtained after simultaneous adsorption, i.e. isolation of the most surface active DoTAB/BLG complex. These specific effects are much less pronounced at the W/H interface. Copyright © 2015 Elsevier Inc

Protective effect of hexane and ethanol extract of piper longum L. On gentamicin-induced hair cell loss in neonatal cultures.

Science.gov (United States)

Yadav, Mukesh Kumar; Choi, June; Song, Jae-Jun

2014-03-01

Gentamicin (GM) is a commonly used aminoglycoside antibiotic that generates free oxygen radicals within the inner ear, which can cause vestibulo-cochlear toxicity and permanent damage to the sensory hair cells and neurons. Piper longum L. (PL) is a well-known spice and traditional medicine in Asia and Pacific islands, which has been reported to exhibit a wide spectrum of activity, including antioxidant activity. In this study, we evaluated the effect of hexane:ethanol (2:8) PL extract (subfraction of PL [SPL] extract) on GM-induced hair cell loss in basal, middle and apical regions in a neonatal cochlea cultures. The protective effects of SPL extract were measured by phalloidin staining of cultures from postnatal day 2-3 mice with GM-induced hair cell loss. The anti-apoptosis activity of SPL extract was measured using double labeling by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and myosin-7a staining. The radical-scavenging activity of SPL extract was assessed using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. SPL extract at a concentration of 1 µg/mL significantly inhibited GM-induced hair cell loss at basal and middle region of cochlea, while 5 µg/mL was effective against apical region hair cell loss. The protective effect of SPL extract was concentration dependent and hair cells retained their stereocilia in explants treated with SPL extract prior to treatment with 0.3 mM GM. SPL extract decreased GM-induced apoptosis of hair cells as assessed by TUNEL staining. The outer hair and inner hair counts were not decreased in SPL extract treated groups in compare to GM treated explants. Additionally, SPL extract showed concentration dependent radical scavenging activity in a DPPH assay. An anti-apoptosis effect and potent radical scavenger activity of SPL extract protects from GM-induced hair cell loss at basal, middle and apical regions in neonatal cochlea cultures.

ANTIBACTERIAL AND ANTIFUNGAL EFFECT OF ETHANOL EXTRACTS, HEXANE AND METHANOLIC FROM THE LEAVES OF Kalanchoe pinnata (Lam. PERS (Malva corama AGAINST MULTI-DRUG RESISTANT STRAINS

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Paloma de Souza Santana

2016-03-01

Full Text Available The infections caused by bacteria and fungi, as well as the subsequent resistance of these microorganisms continue with high incidencesthus studies of medicinal plants and their combination with conventional therapy, are becoming essential. This study examined the antibacterial, antifungal and modifier of resistance to antibiotics and antifungal extracts of ethanol, hexane and methanol from the leaves of Kalanchoe pinnata, used in folk medicine. The phytochemical was performed qualitatively by visual observation of color changes and formation of precipitates after addition of specific reagents, such as ferric chloride (Fecl310% sodium hydroxide (NaOH10%, hydrochloric acid (HCl 1%, acid  acetic acid 5%, ammonium hydroxide (NH4OH 10%, chloroform and  reagent Draggendorff 10%. The analysis for antimicrobial activity was through the microdilution test for determination of minimum inhibitory concentration (MIC and modifying the action of antibiotics (gentamicin and amikacin and antifungals (ketoconazole and fluconazole in association with the extracts. The phytochemicals assays indicated the presence of secondary metabolites such as flavonoids, alkaloids and flabobênicos tannins. In assessing the MIC results were obtained <1024μg/ mL for Candida albicans and Candida krusei. There was synergism between extracts of Kalanchoe pinnata leaves with aminoglycosides and antifungal, reducing the concentration of CIM of multidrug-resistant strains. Our results demonstrate that the extracts of Kalanchoe pinnata have bioactive constituents with antimicrobial activity in vitro. Keywords: Kalcinchoe pinnata, Microorganisms, Synergistic effect, Antifungal, Antibacterial.

Protective action of a hexane crude extract of Pterodon emarginatus fruits against oxidative and nitrosative stress induced by acute exercise in rats

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Alfredo Patrícia P

2005-08-01

Full Text Available Abstract Background The aim of the present work was to evaluate the effect of a hexane crude extract (HCE of Pterodon emarginatus on the oxidative and nitrosative stress induced in skeletal muscle, liver and brain of acutely exercised rats. Methods Adult male rats were subjected to acute exercise by standardized contractions of the tibialis anterior (TA muscle (100 Hz, 15 min and treated orally with the HCE (once or three times with a fixed dose of 498 mg/kg, before and after acute exercise. Serum creatine kinase activity was determined by a kinetic method and macrophage infiltration by histological analyses of TA muscle. Lipid peroxidation was measured as malondialdehyde (MDA levels. Nitric oxide production was evaluated by measuring nitrite formation, using Griess reagent, and nitrotyrosine was assessed by western blotting. Results Serum creatine kinase activities in the controls (111 U/L increased 1 h after acute exercise (443 U/L. Acute exercise also increased the infiltration of macrophages into TA muscle; lipid peroxidation levels in TA muscle (967%, liver (55.5% and brain (108.9%, as well as the nitrite levels by 90.5%, 30.7% and 60%, respectively. The pattern of nitrotyrosine formation was also affected by acute exercise. Treatment with HCE decreased macrophage infiltration, lipid peroxidation, nitrite production and nitrotyrosine levels to control values. Conclusion Acute exercise induced by functional electrical stimulation in rats resulted in increase in lipid peroxidation, nitrite and nitrotyrosine levels in brain, liver and skeletal muscle. The exercise protocol, that involved eccentric muscle contraction, also caused some muscle trauma, associated with over-exertion, leading to inflammation. The extract of P. emarginatus abolished most of these oxidative processes, thus confirming the high antioxidant activity of this oil which infusions are used in folk medicine against inflammatory processes.

Excess molar enthalpies and volumes of binary mixtures of two hydrofluoroethers with hexane, or benzene, or ethanol, or 1-propanol, or 2-butanone at T=298.15 K

International Nuclear Information System (INIS)

Ogawa, Hideo; Karashima, Shinya; Takigawa, Takayo; Murakami, Sachio

2003-01-01

Excess molar enthalpies and volumes at T=298.15 K are reported for binary mixtures of {1,1,2,3,3,3-hexafluoro-1-methoxypropane (HFE-356mec), [CF 3 CHFCF 2 -O-CH 3 ], or 1,1,2,2-tetrafluoro-1-(2,2,2-trifluoroethoxy)ethane (HFE-347pc-f) [CHF 2 CF 2 -O-CH 2 CF 3 ] + hexane (Hx), or benzene (Bz), or ethanol (EtOH), or 1-propanol (PrOH), or 2-butanone (MEK)}. The results of excess molar enthalpies are endothermic over the whole range of concentration, except for the MEK systems, in which excess molar enthalpies are exothermic over the whole range of concentration, and the EtOH systems, in which they are exothermic in the smaller mole fraction range. On the other hand, excess molar volumes are positive over the whole concentration range for all the mixtures. The values of the excess molar enthalpies for the (HFE-347pc-f + Hx) system show the linear composition dependence in the range of ca. 0.3< x<0.7, suggesting the quasi-stable state in solution. The results are explained by means of the destruction of the dipolar interactions and hydrogen bond in the pure component liquids, the difference of the dispersion interactions between the pure component liquid and solution, and the formation of the intermolecular hydrogen bond and dipolar interaction between unlike molecules

Aktivitas Salep Ekstrak Rimpang Kunyit dalam Proses Persembuhan Luka pada Mencit yang Diinduksi Diabetes (THE ACTIVITY OF TURMERIC EXTRACT OINTMENT IN THE WOUND HEALING PROCESS OF INDUCED DIABETIC MICE

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Wiwin Winarsih

2013-07-01

Full Text Available The aim of this study was to evaluate the effectiveness of ethanol turmeric extract ointment in woundhealing process of streptozotocin-induced diabetic mice. Ethyl acetate and hexane fractions of ethanolturmeric extract were studied for their wound-healing properties in the formulation of ointment. Sixty micewere divided into 4 groups : group I was control (normal control, without treatment; group II was diabeticgroup (diabetic, without treatment; group III was diabetic and treated with ethyl acetate fraction ointment,group IV was diabetic and treated with hexane fraction ointment. The diabetic groups were i.p injectedwith 40mg/kg of streptozotocin and all groups were received incision 2 cm on their back skin. The ointmentsof ethyl acetate and hexane fraction were given topically twice a day. Three mice from each groups werenecropsied at 2nd, 4th, 7th, 14th and 21st days post incision (pi for gross pathological and histopathologicalevaluation of the injured skin. Gross examination revealed that the ethyl acetate and hexane fractionointment groups showed better result on wound-healing process compared to the diabetic group.Microscopically, the ethyl acetate and hexane fraction ointment groups showed faster neovascularizationand reepithelialization compared to the diabetic group. In comparison with the diabetic group, the ethylacetate and hexane fraction ointment groups showed fewer neutrophils infiltration which indicated antiinflammatory activities of ethyl acetate and hexane fractions. Based on the macroscopic and microscopicobservation, the ointments of ethyl acetate and hexane fraction have properties to promote wound healingin diabetic mice.

The ignition delay, laminar flame speed and adiabatic temperature characteristics of n-pentane, n-hexane and n-heptane under O{sub 2}/CO{sub 2} atmosphere

Energy Technology Data Exchange (ETDEWEB)

Zhao, Ran [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion; Wuhan Textile Univ. (China). School of Environment and Urban Construction; Liu, Hao; Zhong, Xiaojiao; Wang, Zijian; Jin, Ziqin; Qiu, Jianrong [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion; Chen, Yingming [Wuhan Textile Univ. (China). School of Environment and Urban Construction

2013-07-01

Oxy-fuel (O{sub 2}/CO{sub 2}) combustion is one of the several promising new technologies which can realize the integrated control of CO{sub 2}, SO{sub 2}, NO{sub X} and other pollutants. However, when fuels are burned in the high CO{sub 2} concentration environment, the combustion characteristics can be very different from conventional air-fired combustion. Such changes imply that the high CO{sub 2} concentration atmosphere has impacts on the combustion processes. In this paper, the ignition time, laminar flame speed and adiabatic temperature property of C{sub 5} {proportional_to} C{sub 7} n-alkane fuels were studied under both ordinary air atmosphere and O{sub 2}/CO{sub 2} atmospheres over a wide range of CO{sub 2} concentration in the combustion systems. A new unified detailed chemical kinetic model was validated and used to simulate the three liquid hydrocarbon fuel's flame characteristics. Based on the verified model, the influences of various parameters (atmosphere, excess oxygen ratio, O{sub 2} concentration, CO{sub 2} concentration, and alkane type) on the C{sub 5} {proportional_to} C{sub 7} n-alkane's flame characteristics were systematically investigated. It can be concluded that high CO{sub 2} concentration atmosphere has negative effect on n-pentane, n-hexane and n-heptane flame's ignition, laminar flame speed and adiabatic temperature. Besides, this work confirms that high CO{sub 2} concentration atmosphere's chemical effects play a pronounced role on the flame characteristics, especially for the ignition time property.

Antioxidant, antimicrobial, antitumor, and cytotoxic activities of an important medicinal plant (Euphorbia royleana from Pakistan

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Aisha Ashraf

2015-03-01

Full Text Available The aim of present study was to evaluate antioxidant, antimicrobial, and antitumor activities of methanol, hexane, and aqueous extracts of fresh Euphorbia royleana. Total phenolic and flavonoid contents were estimated as gallic acid and querectin equivalents, respectively. Antioxidant activity was assessed by scavenging of free 2,2′- diphenyl-1-picrylhydrazyl radicals and reduction of ferric ions, and it was observed that inhibition values increase linearly with increase in concentration of extract. The results of ferric reducing antioxidant power assay showed that hexane extract has maximum ferric reducing power (12.70 ± 0.49 mg gallic acid equivalents/g of plant extract. Maximum phenolic (47.47 ± 0.71 μg gallic acid equivalents/mg of plant extract and flavonoid (63.68 ± 0.43 μg querectin equivalents/mg of plant extract contents were also found in the hexane extract. Furthermore, we examined antimicrobial activity of the three extracts (methanol, hexane, aqueous against a panel of microorganisms (Escherichia coli, Bacillus subtillis, Pasteurella multocida, Aspergillus niger, and Fusarium solani by disc-diffusion assay, and found the hexane extract to be the best antimicrobial agent. Hexane extract was also observed as to be most effective in a potato disc assay. As hexane extract showed potent activity in all the investigated assays, it was targeted for cytotoxic assessment. Maximum cytotoxicity (61.66% by hexane extract was found at 800 μg/mL. It is concluded that investigated extracts have potential for isolation of antioxidant and antimicrobial compounds for the pharmaceutical industry.

Effect of physical exertion on the biological monitoring of exposure to various solvents following exposure by inhalation in human volunteers: II. n-Hexane.

Science.gov (United States)

Tardif, Robert; Nadeau, Véronique; Truchon, Ginette; Brochu, Martin

2007-07-01

This study evaluated the impact of physical exertion on two n-hexane (HEX) exposure indicators in human volunteers exposed under controlled conditions in an inhalation chamber. A group of four volunteers (two women, two men) were exposed to HEX (50 ppm; 176 mg/m(3)) according to several scenarios involving several periods when volunteers performed either aerobic (AERO), muscular (MUSC), or both AERO/MUSC types of exercise. The target intensities for 30-min exercise periods separated by 15-min rest periods were the following: REST, 50W AERO [time-weighted average intensity including resting period (TWAI): 38W], 50W AERO/MUSC (TWAI: 34W), 100W AERO/MUSC (TWAI: 63W), and 100W AERO (TWAI: 71W) for 7 hr (two 3-hr exposure periods separated by 1 hr without exposure) and 50W MUSC for 3 hr (TWAI: 31W). Alveolar air and urine samples were collected at different time intervals before, during, and after exposure to measure unchanged HEX in expired air (HEX-A) and urinary 2,5-hexanedione (2,5-HD). HEX-A levels during exposures involving AERO activities (TWAI: 38W and 71W) were significantly enhanced (approximately +14%) compared with exposure at rest. MUSC or AERO/MUSC exercises were also associated with higher HEX-A levels but only at some sampling times. In contrast, end-of-exposure (7 hr) urinary 2,5-HD (mean +/- SD) was not modified by physical exertion: 4.14 +/- 1.51 micromol/L (REST), 4.02 +/- 1.52 micromol/L (TWAI 34W), 4.25 +/- 1.53 micromol/L (TWAI 38W), 3.73 +/- 2.09 micromol/L (TWAI 63W), 3.6 +/- 1.34 micromol/L (TWAI 71W) even though a downward trend was observed. Overall, this study showed that HEX kinetics is practically insensitive to moderate variations in workload intensity; only HEX-A levels increased slightly, and urinary 2,5-HD levels remained unchanged despite the fact that all types of physical exercise increased the pulmonary ventilation rate.

Fungitoxic activity avaliation of the hexane and methanol extracts of copaiba plant leavesCopaifera langsdorffi Desfon Avaliação da atividade fungitóxica dos extratos foliares hexânico e metanólico da Copaifera langsdorffi Desfon

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Ana Carolina Lourenço Amorim

2004-04-01

Full Text Available The fungitoxicity of hexane and methanol extracts of copaiba plants were evaluated by biological tests against the phytopathogens Colletotrichum gloeosporioides and Bipolaris sorokiniana. These extracts were chosen because they presented the highest yields in the extraction at room temperature. The biological material was obtained from the Department of Phytopathology of the UFLA, transplanted in BDA (C. gloeosporioides and PCA (B. sorokiniana culture media and incubated in a germination chamber with control of light and temperature. Five treatments (0/100/200/400/800 ppm were used with three repetitions of each, and four mutually perpendicular radii, were measured in centimeters from the mycelial center. The formula for the Mycelial Growth Index (MGI was applied to the values obtained for statistical analyses. A 32% reduction in the growth of B. sorokiniana was observed in the presence of the methanol extract, while the hexane extract was effective against both of the phytopathogens, resulting in a 49% reduction in the growth of B. sorokiniana and an 18% reduction in the growth of C. gloeosporioides.Avaliou-se a fungitoxicidade dos extratos hexânico e metanólico do óleo copaíba por meio de ensaios biológicos contra os fitopatógenos Colletotrichum gloeosporioides e Bipolaris sorokiniana. Os referidos extratos foram escolhidos em razão dos melhores rendimentos obtidos na extração a frio. O material biológico foi obtido na UFLA no Departamento de Fitopatologia, repicado em meio de cultura BDA (C. gloeosporioides e PCA (B. sorokiniana e incubados em câmara de germinação com controle de temperatura e luz. Empregaram-se cinco tratamentos (0/100/200/400/800 ppm, realizando-se três repetições e avaliando-se quatro raios, medidos em centímetros, a partir do micélio central. Os valores aferidos foram aplicados à fórmula do Índice de Crescimento Micelial (ICM para as análises estatísticas. Observou-se que o extrato metan

Estimating dermal transfer from PCB-contaminated porous surfaces.

Science.gov (United States)

Slayton, T M; Valberg, P A; Wait, A D

1998-06-01

Health risks posed by dermal contact with PCB-contaminated porous surfaces have not been directly demonstrated and are difficult to estimate indirectly. Surface contamination by organic compounds is commonly assessed by collecting wipe samples with hexane as the solvent. However, for porous surfaces, hexane wipe characterization is of limited direct use when estimating potential human exposure. Particularly for porous surfaces, the relationship between the amount of organic material collected by hexane and the amount actually picked up by, for example, a person's hand touch is unknown. To better mimic PCB pickup by casual hand contact with contaminated concrete surfaces, we used alternate solvents and wipe application methods that more closely mimic casual dermal contact. Our sampling results were compared to PCB pickup using hexane-wetted wipes and the standard rubbing protocol. Dry and oil-wetted samples, applied without rubbing, picked up less than 1% of the PCBs picked up by the standard hexane procedure; with rubbing, they picked up about 2%. Without rubbing, saline-wetted wipes picked up 2.5%; with rubbing, they picked up about 12%. While the nature of dermal contact with a contaminated surface cannot be perfectly reproduced with a wipe sample, our results with alternate wiping solvents and rubbing methods more closely mimic hand contact than the standard hexane wipe protocol. The relative pickup estimates presented in this paper can be used in conjunction with site-specific PCB hexane wipe results to estimate dermal pickup rates at sites with PCB-contaminated concrete.

Molecular simulation of CO chemisorption on Co(0001) in presence of supercritical fluid solvent: A potential of mean force study

Energy Technology Data Exchange (ETDEWEB)

Asiaee, Alireza; Benjamin, Kenneth M., E-mail: kenneth.benjamin@sdsmt.edu [Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, 501 E. Saint Joseph St., Rapid City, South Dakota 57701 (United States)

2016-08-28

For several decades, heterogeneous catalytic processes have been improved through utilizing supercritical fluids (SCFs) as solvents. While numerous experimental studies have been established across a range of chemistries, such as oxidation, pyrolysis, amination, and Fischer-Tropsch synthesis, still there is little fundamental, molecular-level information regarding the role of the SCF on elementary heterogeneous catalytic steps. In this study, the influence of hexane solvent on the adsorption of carbon monoxide on Co(0001), as the first step in the reaction mechanism of many processes involving syngas conversion, is probed. Simulations are performed at various bulk hexane densities, ranging from ideal gas conditions (no SCF hexane) to various near- and super-critical hexane densities. For this purpose, both density functional theory and molecular dynamics simulations are employed to determine the adsorption energy and free energy change during CO chemisorption. Potential of mean force calculations, utilizing umbrella sampling and the weighted histogram analysis method, provide the first commentary on SCF solvent effects on the energetic aspects of the chemisorption process. Simulation results indicate an enhanced stability of CO adsorption on the catalyst surface in the presence of supercritical hexane within the reduced pressure range of 1.0–1.5 at a constant temperature of 523 K. Furthermore, it is shown that the maximum stability of CO in the adsorbed state as a function of supercritical hexane density at 523 K nearly coincides with the maximum isothermal compressibility of bulk hexane at this temperature.

Studies of the influence of different anions on extraction of neodymium with di(1-methylheptyl)methyl phosphonate

International Nuclear Information System (INIS)

Chun-Hui Huang; Rong-Fang Xi; Hai Guo; Guang-Xian Xu

1988-01-01

A study was made on extraction of Nd(NCS) 3 , Nd(ClO 4 ) 3 , Nd(NO 3 ) 3 by di-(1-methylhexyl)methyl phosphonate (P-350) in hexane. ΔG 0 (kJ/mol), ΔH 0 (kJ/mol) and ΔS 0 (kJ/mol) were calculated. They are equal to: -9.719, -29.92, -67.78 for P-350(hexane)-Nd(NCS) 3 system; 3.752, -74.31, -261.9 for P-350((hexane)-Nd(ClO 4 ) 3 system; 2.265, -22.69, -83.68 for P-350(hexane)-Nd(NO 3 ) 3 system. Structure of extracted complexes in hexane solution and corresponding solid complexes were correlated with triphenylphosphine oxide as P-350 model. Data of IR-spectroscopy show, that absorption bands of complexes in saturated organic solvents or in the solid phase are shifted to the region of lower frequencies as compared to absorption bands of corresponding salts. This testifies to similarity of complex structures in both phases

Desolventizing of soybean oil/azeotrope mixtures using ceramic membranes.

Science.gov (United States)

de Melo, Jonas R M; Tiggeman, Lidia; Rezzadori, Katia; Steffens, Juliana; Palliga, Marshall; Oliveira, J Vladimir; Di Luccio, Marco; Tres, Marcus V

2017-08-01

This work investigates the use of ceramic membranes with different molecular weight cut-offs (MWCOs: 5, 10 and 20 kDa) to desolventize azeotropic solvent mixtures (ethanol/n-hexane and isopropyl alcohol/n-hexane) from soybean oil/azeotrope micelles. Results show that a decrease in the MWCO of a membrane and an increase in the solvent mass ratio in the mixture resulted in a significant reduction in the permeate flux. The 20 kDa membrane presented the highest permeate flux, 80 and 60 kg/m 2 h for the soybean oil/n-hexane/isopropyl alcohol and soybean oil/n-hexane/ethanol azeotropes, respectively, for an oil to solvent ratio of 1:3 (w/w). The highest oil retention was found using the n-hexane/isopropyl alcohol azeotrope, around 25% in the membrane with the lowest MWCO, that is, 5 kDa. It is shown that the azeotropic mixtures provided intermediate characteristics compared to the original pure solvent behavior.

Temperature Dependence of the Inhibition of Positronium by Chlorine- Substituted Hydrocarbons in Non-Polar Liquids

DEFF Research Database (Denmark)

Wikander, G.; Mogensen, O.E.; Pedersen, Niels Jørgen

1984-01-01

Positron annihilation lifetime spectra were measured for solutions of 1,2,3,5-C6H2Cl4 in hexane, toluene, m-xylene and mesitylene, CCl4 in hexane and toluene, and C2HCl3 in n-hexane for concentrations below 1 M and at various temperatures between −30°C and 67°C. The Ps inhibition by C6H2Cl4 was r...

[Oxidation behavior and kinetics of representative VOCs emitted from petrochemical industry over CuCeOx composite oxides].

Science.gov (United States)

Chen, Chang-Wei; Yu, Yan-Ke; Chen, Jin-Sheng; He, Chi

2013-12-01

CuCeOx composite catalysts were synthesized via coprecipitation (COP-CuCeO,) and incipient impregnation (IMP-CuCeOx) methods, respectively. The physicochemical properties of the samples were characterized by XRD, low-temperature N2 sorption, H2-TPR and O2-TPD. The influences of reactant composition and concentration, reaction space velocity, O2 content, H2O concentration, and catalyst type on the oxidation behaviors of benzene, toluene, and n-hexane emitted from petrochemical industry were systematically investigated. In addition, the related kinetic parameters were model fitted. Compared with IMP-CuCeOx, COP-CuCeOx had well-dispersed active phase, better low-temperature reducibility, and more active surface oxygen species. The increase of reactant concentration was unfavorable for toluene oxidation, while the opposite phenomenon could be observed in n-hexane oxidation. The inlet concentration of benzene was irrelevant to its conversion under high oxidation rate. The introduction of benzene obviously inhibited the oxidation of toluene and n-hexane, while the presence of toluene had a positive effect on beuzene conversion. The presence of n-hexane could promote the oxidation of toluene, while toluene had a negative influence on e-hexane oxidation. Both low space velocity and high oxygen concentration were beneficial for the oxidation process, and the variation of oxygen content had negligible effect on n-hexane and henzene oxidation. The presence of H2O noticeably inhibited the oxidation of toluene, while significantly accelerated the oxidation procedure of henzene and n-hexane. COP-CuCeOx had superior catalytic performance for toluene and benzene oxidation, while IMP-CuCeOx showed higher n-hexane oxidation activity under dry condition. The oxidation behaviors under different conditions could be well fitted and predicted by the pseudo first-order kinetic model.

Avaliação dos parâmetros de solubilidade de Hildebrand/Hansen na seleção de solventes para a extração de pesticidas organoclorados do solo

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Ricardo D Villa

2011-09-01

Full Text Available This work evaluated the use of the Hildebrand/Hansen solubility parameters for selection of solvents for extraction of the organochlorine pesticides pp' DDT, pp' DDE, Aldrin and a-Endossulfan from soil using columns packed with Al2O3. The mixtures hexane:dichloromethane (7:3; v/v, hexane:acetonitrile (1:1; v/v, hexane:acetone (1:1; v/v and pure hexane were chosen as extracting solutions. In the addition and recovery tests, different extraction solutions provided high recoveries percentages (>75% with coefficients of variation below 15%. The recoveries are in agreement with the Hildebrand/Hansen parameters, demonstrating its applicability in the selection of extracting solution and in the replacement of toxic solvents, as dichloromethane

Toxic Effects of Couroupita guianensis Against Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae).

Science.gov (United States)

Baskar, K; Ignacimuthu, S; Jayakumar, M

2015-02-01

Laboratory experiments were conducted to find out the efficacy of different crude extracts and fractions of Couroupita guianensis (Lecythidaceae) against Spodoptera litura (Fabricius). Results revealed that hexane, chloroform and ethyl acetate extracts of C. guianensis showed larvicidal and pupicidal activities against S. litura. Maximum larvicidal activity (68.66%) was observed in hexane extract at 5.0% concentration followed by chloroform and ethyl acetate extracts, and least LC50 value of 2.64% was observed in hexane extract. A 100% pupicidal activity was observed in hexane extract. Based on the efficacy of crude extracts, the effective crude extract (hexane extract) was further fractionated and subjected to screening for biological activities against S. litura. Among the eight fractions isolated from the hexane extract, fraction 8 showed maximum antifeedant activity (81. 8%) and larvicidal activity (76.9%) at 1000-ppm concentration; this fraction showed least LC50 value of 375.92 ppm for larvicidal activity. Cent per cent pupicidal activity was recorded. Reduced midgut and hemolymph protein contents were observed at 1000 ppm of fraction 8. Histopathological studies revealed that fraction 8 severely damaged the midgut cells of S. litura. This fraction could be used to develop botanical formulation to control agricultural pests.

Antioxidant activities of different solvent extracts of Piper retrofractum Vahl. using DPPH assay

Science.gov (United States)

Jadid, Nurul; Hidayati, Dewi; Hartanti, Sylviana Rosyda; Arraniry, Byan Arasyi; Rachman, Rizka Yuanita; Wikanta, Wiwi

2017-06-01

Piper retrofractum Vahl., which belongs to the family Piperaceae, is geographically dispersed in tropical region including Indonesia. They are well-known spice possessing high medicinal properties. This study aimed to determine the antioxidant activity of P. retrofractum fruit, extracted with different solvents (methanol, ethyl acetate, n-hexane) using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. This research was carried out using different concentrations of methanol, ethyl acetate, and n-hexane extracts, (0, 5, 15, 30, 45, 60 ppm). Ascorbic acid was also used as positive antioxidant control. The percentage of inhibition and IC50 were measured. The results showed that the DPPH free radicals were scavenged by all plant extracts in a concentration dependent manner. Moreover, the IC50 values for DPPH radicals with methanol, ethyl acetate and n-hexane extract of the P. retrofractum Vahl. were found to be 101.74; 66.12 and 57.66 ppm, respectively. Interestingly, the IC50 value of n-hexane extract (57.66 ppm) was lower than ascorbic acid (66.12 ppm), indicating that n-hexane extract was a more potent scavenger of free radicals than methanol and ethyl acetate extracts. Taken together, our results suggested that n-hexane extract of P. Retrofractum Vahl. might contain potential antioxidant compounds.

Polymeric Microelectronics.

Science.gov (United States)

1981-06-01

Swelling Procedure For Crosslinked Gel 2A.1 Materials: Spectral grade hexane Petri dish with glass plate cover Planchette Balance Vacuum oven 2A.2...Uncrosslinked Material) To determine the amount of uncrosslinked material decant the dupernatant hexane into a weighed planchette . Wash the gel and...swelling flask or dish with hexane again and pour into planchette . Place the planchette and its contents into a vacuum oven at 350C until the contents

Evaluation of in vitro antioxidant potential of different polarities stem crude extracts by different extraction methods of Adenium obesum

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Mohammad Amzad Hossain

2014-09-01

Full Text Available Objective: To select best extraction method for the isolated antioxidant compounds from the stems of Adenium obesum. Methods: Two methods used for the extraction are Soxhlet and maceration methods. Methanol solvent was used for both extraction method. The methanol crude extract was defatted with water and extracted successively with hexane, chloroform, ethyl acetate and butanol solvents. The antioxidant potential for all crude extracts were determined by using 1, 1-diphenyl-2- picrylhydrazyl method. Results: The percentage of extraction yield by Soxhlet method is higher compared to maceration method. The antioxidant potential for methanol and its derived fractions by Soxhlet extractor method was highest in ethyl acetate and lowest in hexane crude extracts and found in the order of ethyl acetate>butanol>water>chloroform>methanol>hexane. However, the antioxidant potential for methanol and its derived fractions by maceration method was highest in butanol and lowest in hexane followed in the order of butanol>methanol>chloroform>water>ethyl acetate>hexane. Conclusions: The results showed that isolate antioxidant compounds effected on the extraction method and condition of extraction.

Study of the selective abstration reaction of the hydrogen atom in the radiolysis and photolysis of alkane mixture at 77 K

International Nuclear Information System (INIS)

Guedes, S.M.L.

1979-01-01

The occurence of the selective abstraction reaction of the solute hydrogen atom by hydrogen atom produced during radiolysis or photolysis of the systems such as neopentane/cyclo-hexane/HI, neopentane/2,3 dimethylbutane, n-pentane/HI/cyclo-hexane and cyclo-hexane/HI/n-pentane, at 77 K is studied. Experiments have been undertaken on the kinetics nature of the active species, the H atom, during radiolysis and photolysis of the neopentane/cyclo-hexane/HI system at 77 K, presenting competitive reactions. Studies have also been made on the occurrence of the selective abstraction reaction in inverted systems, in which the concentrations of the components of a system are so much altered that the solute becomes the solvent and vice-versa, in the other system. By means of photolysis at 77 K, it has been observed that for the two systems constitued by the cyclo-hexane and n-pentane the selective abstraction reaction occurs. However, for radiolysis of that same two systems it has been observed that only the hydrogen atom abstraction reaction corresponding to the solvent occurs. (Author) [pt

EKSTRAKSI DAN ANALISIS FITOSTEROL LEMBAGA GANDUM [Extraction and analysis of Phytosterol from wheat germ (Triticum sp.

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Latifah K Darusman3

2005-04-01

Full Text Available Phytosterol may reduce the absorption of cholesterol, and used for preventing atherosclerosis. It is limited in soybean, but potentially abundant in wheat germ. Research on the utilization of wheat germ sterol had not been reported so far. Many aspects of germ sterol extraction from wheat germ and its characteristics were still unknown. In this research, the best extraction method, kinds and content of phytosterol from wheat germ were investigated.This research consisted of two steps: (1 extraction of phytosterol directly form whole germ and ground germ using hexane, and indirect extraction through germ oil using hexane and mixed solvent of hexane and ethanol, and direct extraction from ground germ using ethanol; (2 analysis of the type and content of phytosterol in the crude extract through the following steps: preparation of crude extract, fractionation, and analysis.Results showed that indirect extraction through germ oil was considered as the best method which yielded 1.37% of phytosterol. The highest yield was obtained when extracted using a mixed solvent of hexane – ethanol 82:18. However, the odor of ethanol and hexane (gasoline like odor was still detected. The solvent’s ratio of hexane to ethanol at 1:2 resulted better odor of the extract. Extraction of sterol using ethanol yielded 18.39% of sterol when the ratio of germ to ethanol at 1:10 (w/v was applied.Results of quantitative analysis on the main component of crude extract of wheat germ sterol showed that the total content of sterol extracted with mixed solvent was higher than those extracted with ethanol. The ratio of hexane to ethanol at 1:1 (v/v gave higher content of total sterol, stigmasterol and campesterol, whereas higher content of -sitosterol was produced at the solvent’s ratio of hexane to ethanol at 1:2 (v/v.

(Vapour + liquid) equilibria of ternary systems with ionic liquids using headspace gas chromatography

International Nuclear Information System (INIS)

Mokhtarani, Babak; Gmehling, Juergen

2010-01-01

(Vapour + liquid) equilibrium (VLE) data for the ternary systems (hexane + benzene), (hexane + cyclohexane), (benzene + cyclohexane), and (ethanol + water) with an ionic liquid as entrainer for extractive distillation were measured by headspace gas chromatography. As ionic liquids, 1-hexyl-3-methyl-imidazolium bis (trifluoromethyl-sulfonyl) imide [HMIM][BTI], 1-octyl-3-methyl-imidazolium bis (trifluoromethyl-sulfonyl) imide [OMIM][BTI], 1-octyl-3-methyl-imidazolium trifluoro-methanesulfonate [OMIM][OTF], and 1-butyl-3-methyl-imidazolium trifluoro-methanesulfonate [BMIM][OTF] were used. The experimental data show that the ionic liquids investigated have a great influence on the separation factors of the systems (hexane + benzene), (hexane + cyclohexane), and (benzene + cyclohexane). The experimental data were compared with the predicted results using mod. UNIFAC (Do). The predicted results are in good agreement with the experimental data.

(Vapour + liquid) equilibria of ternary systems with ionic liquids using headspace gas chromatography

Energy Technology Data Exchange (ETDEWEB)

Mokhtarani, Babak [Chemistry and Chemical Engineering Research Center of Iran, P.O. Box 14335-186, Tehran (Iran, Islamic Republic of); Gmehling, Juergen, E-mail: gmehling@tech.chem.uni-oldenburg.d [Carl von Ossietzky Universitaet Oldenburg, Technische Chemie, D-26111 Oldenburg (Germany)

2010-08-15

(Vapour + liquid) equilibrium (VLE) data for the ternary systems (hexane + benzene), (hexane + cyclohexane), (benzene + cyclohexane), and (ethanol + water) with an ionic liquid as entrainer for extractive distillation were measured by headspace gas chromatography. As ionic liquids, 1-hexyl-3-methyl-imidazolium bis (trifluoromethyl-sulfonyl) imide [HMIM][BTI], 1-octyl-3-methyl-imidazolium bis (trifluoromethyl-sulfonyl) imide [OMIM][BTI], 1-octyl-3-methyl-imidazolium trifluoro-methanesulfonate [OMIM][OTF], and 1-butyl-3-methyl-imidazolium trifluoro-methanesulfonate [BMIM][OTF] were used. The experimental data show that the ionic liquids investigated have a great influence on the separation factors of the systems (hexane + benzene), (hexane + cyclohexane), and (benzene + cyclohexane). The experimental data were compared with the predicted results using mod. UNIFAC (Do). The predicted results are in good agreement with the experimental data.

Phytochemical screening of different extracts of Kalanchoe laciniata

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Maria Manan

2015-06-01

Full Text Available Alkaloids, tannins, saponins, steroids, terpenoids and flavonoids distribution in n-hexane and aqueous-methanolicextract of kalanchoelaciniata was assessed and compared. The present study was carried out to study the phytochemical constituents of Kalanchoe laciniata. Aqueous-methanol and n-hexane were the solvents used for the extraction of the plant. Phytochemical analysis was carried out on both of these extracts, indicated that n-hexane extract constitutes tannins, terpenoids on the other hand aqueous-methanolic extract contains saponins, tannins, terpenoids, flavonoids, glycosides  and anthraquinones. 

Catalytic purification of waste gases containing VOC mixtures with Ce/Zr solid solutions

International Nuclear Information System (INIS)

Gutierrez-Ortiz, Jose I.; De Rivas, Beatriz; Lopez-Fonseca, Ruben; Gonzalez-Velasco, Juan R.

2006-01-01

This study has been undertaken to investigate the efficiency of ceria, zirconia, and Ce x Zr 1-x O 2 mixed oxides as catalysts for the vapour-phase destruction in air of single model VOCs (n-hexane, 1,2-dichloroethane and trichloroethylene) and non-chlorinated VOC/chlorinated VOC binary mixtures. Considering all catalyst compositions examined for the individual destruction of these compounds, activity for complete oxidation decreased in the following order: n-hexane 0.5 Zr 0.5 O 2 and Ce 0.15 Zr 0.85 O 2 ) were different than that with the best performance for n-hexane oxidation (CeO 2 ). Concerning chlorinated VOCs conversion, it was observed that notable improvements in catalyst activity of CeO 2 could be achieved through structural doping with Zr ions. Mixed oxides exhibited promoted redox and acid properties, which resulted catalytically relevant for the oxidation of 1,2-dichloroethane and trichloroethylene. In contrast, the combustion of n-hexane was essentially controlled by surface oxygen species, which were more abundant on CeO 2 . Attainment of high n-hexane conversions with CeO 2 was also attributed in part to the hydrophobicity of the support and the reduced interaction with carbon dioxide. Significant 'mixture effects' on both activity and selectivity were noticed when a given chlorinated feed was decomposed in the presence of n-hexane. On one hand, each VOC decreased the reactivity of the other relative to that of the pure compound resulting in higher operating temperatures to achieve adequate destruction. Competitive adsorption played an important role in the reciprocal inhibition effects detected with all catalysts. On the other hand, the selectivity to HCl was noticeably enhanced when n-hexane was co-fed, probably due to the increased presence of water generated as an oxidation product. (author)

Sea Cucumber Lipid-Soluble Extra Fraction Prevents Ovalbumin-Induced Allergic Airway Inflammation.

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Lee, Da-In; Kang, Shin Ae; Md, Anisuzzaman; Jeong, U-Cheol; Jin, Feng; Kang, Seok-Joong; Lee, Jeong-Yeol; Yu, Hak Sun

2018-01-01

In a previous study, our research group demonstrated that sea cucumber (Apostichopus japonicus) extracts ameliorated allergic airway inflammation through CD4 + CD25 + Foxp3 + T (regulatory T; Treg) cell activation and recruitment to the lung. In this study, we aimed to determine which components of sea cucumber contribute to the amelioration of airway inflammation. We used n-hexane fractionation to separate sea cucumber into three phases (n-hexane, alcohol, and solid) and evaluated the ability of each phase to elevate Il10 expression in splenocytes and ameliorate symptoms in mice with ovalbumin (OVA)/alum-induced asthma. Splenocytes treated with the n-hexane phase showed a significant increase in Il10 expression. In the n-hexane phase, 47 fatty acids were identified. Individual fatty acids that comprised at least 5% of the total fatty acids were 16:0, 16:1n-7, 18:0, 18:1n-7, 20:4n-6, and 20:5n-3 (eicosapentaenoic acid). After administering the n-hexane phase to mice with OVA/alum-induced asthma, their asthma symptoms were ameliorated. Several immunomodulatory effects were observed in the n-hexane phase-pretreated group, compared with a vehicle control group. First, eosinophil infiltration and goblet cell hyperplasia were significantly reduced around the airways. Second, the concentrations of Th2-related cytokines (IL-4, IL-5, and IL-13) and Th17-related cytokines (IL-17) were significantly decreased in the spleen and bronchoalveolar lavage fluid (BALF). Finally, the concentrations of TGF-β and IL-10, which are associated with Treg cells, were significantly increased in the BALF and splenocyte culture medium. In conclusion, a fatty acid-rich fraction (n-hexane phase) of sea cucumber extract ameliorated allergic airway inflammation in a mouse model.

Antileishmanial potential of medicinal plant extracts from the North-West of Morocco

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Abdelhakim Bouyahya

2018-03-01

Full Text Available The aim of this study is to evaluate the antileishmanial activity of selected medicinal plants from the North-West of Morocco. Plant extracts were prepared by maceration using methanol, ethanol, and n-hexane. The antileishmanial activity was evaluated against Leishmania major, Leishmania tropica, and Leishmania infantum using MTT (3-(4.5-dimethylthiazol-2yl-2.5-diphenyltetrazolium bromide assay. All plant extracts showed a reducing in cell promastigotes viability with variability depending on tested strains and type of extracts. The n-hexane extract showed the highest antileishmanial activity and L. infantum was the most sensitive parasite. The best growth inhibition was observed with Cistus crispus n-hexane extract against L. major (IC50 = 47.29 ± 2.25 μg/mL, Arbutus unedo n-hexane extract against L. infantum (IC50 = 64.05 ± 1.44 μg/mL and Arbutus unedo n-hexane extract against L. tropica (IC50 = 79.57 ± 2.66 μg/mL. Considering these results, medicinal plants from the North-West of Morocco could constitute a promoter source for antileishmanial compounds.

The influence of extraction methods on composition and antioxidant properties of rice bran oil

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Noppawat Pengkumsri

2015-09-01

Full Text Available AbstractThe current study was employed to assess the influence of the different extraction methods on total tocols, γ-oryzanol content, and antioxidant properties of Chiang Mai Black rice, Mali Red rice, and Suphanburi-1 Brown rice bran oil. Rice bran oil (RBO was extracted by Hexane, Hot pressed, Cold pressed, and Supercritical Fluid Extraction (SFe methods. High yield of RBO was extracted by hexane and SFe methods. Total and subgroups of tocols, and γ-oryzanol content were determined by HPLC. The hexane extracted sample accounts for high content of γ-oryzanol and tocols. Besides, all of RBO extracts contain a significantly high amount of γ-tocotrienol. In vitro antioxidant assay results indicated that superior quality of oil was recovered by hexane extraction. The temperature in the extraction process also affects the value of the oil. Superior quality of oil was recovered by hexane extraction, in terms of phytochemical contents and antioxidant properties compared to other tested extraction methods. Further, thorough study of factors compromising the quality and quantity of RBO recovery is required for the development of enhanced functional foods and other related products.

Improved extraction procedure for carotenoids from human milk.

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Schweigert, F J; Hurtienne, A; Bathe, K

2000-05-01

An improved method for the extraction of the major carotenoids from human milk is described. Carotenoids were extracted from milk first with ethanol and n-hexane. Then, polar xanthophylls were extracted from n-hexane into ethanol/water. The remaining n-hexane was evaporated, the residue combined with the ethanolic milk fraction and the mixture briefly saponified. Carotenoids were extracted from the hydrolysate with n-hexane, combined with the polar xanthophylls from the non-saponified ethanol/water-extract and separated by HPLC. Using this method we were able to significantly improve the recovery of xanthophylls such as lutein and zeaxanthin from human milk. The recovery rate of all carotenoids was > 90%. This method might not only be of value for milk but should be especially useful in the extraction of carotenoids from human tissues such as the adipose tissue.

A hexane fraction of guava Leaves (Psidium guajava L.) induces anticancer activity by suppressing AKT/mammalian target of rapamycin/ribosomal p70 S6 kinase in human prostate cancer cells.

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Ryu, Nae Hyung; Park, Kyung-Ran; Kim, Sung-Moo; Yun, Hyung-Mun; Nam, Dongwoo; Lee, Seok-Geun; Jang, Hyeung-Jin; Ahn, Kyoo Seok; Kim, Sung-Hoon; Shim, Bum Sang; Choi, Seung-Hoon; Mosaddik, Ashik; Cho, Somi K; Ahn, Kwang Seok

2012-03-01

This study was carried out to evaluate the anticancer effects of guava leaf extracts and its fractions. The chemical compositions of the active extracts were also determined. In the present study, we set out to determine whether the anticancer effects of guava leaves are linked with their ability to suppress constitutive AKT/mammalian target of rapamycin (mTOR)/ribosomal p70 S6 kinase (S6K1) and mitogen-activated protein kinase (MAPK) activation pathways in human prostate cancer cells. We found that guava leaf hexane fraction (GHF) was the most potent inducer of cytotoxic and apoptotic effects in PC-3 cells. The molecular mechanism or mechanisms of GHF apoptotic potential were correlated with the suppression of AKT/mTOR/S6K1 and MAPK signaling pathways. This effect of GHF correlated with down-regulation of various proteins that mediate cell proliferation, cell survival, metastasis, and angiogenesis. Analysis of GHF by gas chromatography and gas chromatography-mass spectrometry tentatively identified 60 compounds, including β-eudesmol (11.98%), α-copaene (7.97%), phytol (7.95%), α-patchoulene (3.76%), β-caryophyllene oxide (CPO) (3.63%), caryophylla-3(15),7(14)-dien-6-ol (2.68%), (E)-methyl isoeugenol (1.90%), α-terpineol (1.76%), and octadecane (1.23%). Besides GHF, CPO, but not phytol, also inhibited the AKT/mTOR/S6K1 signaling pathway and induced apoptosis in prostate cancer cells. Overall, these findings suggest that guava leaves can interfere with multiple signaling cascades linked with tumorigenesis and provide a source of potential therapeutic compounds for both the prevention and treatment of cancer.

Inhibition of Quorum Sensing-Controlled Virulence Factor Production in Pseudomonas aeruginosa PAO1 by Ayurveda Spice Clove (Syzygium Aromaticum Bud Extract

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Kok-Gan Chan

2012-03-01

Full Text Available Quorum sensing controls the virulence determinants in most proteobacteria. In this work, the hexane, chloroform and methanol extracts of an Ayurveda spice, namely clove (Syzygium aromaticum, shown anti-quorum sensing activity. Hexane and methanol extracts of clove inhibited the response of C. violaceum CV026 to exogenously supplied N‑hexanoylhomoserine lactone, in turn preventing violacein production. Chloroform and methanol extracts of clove significantly reduced bioluminescence production by E. coli [pSB1075] grown in the presence of N-(3-oxododecanoyl-L-homoserine lactone. We demonstrated that clove extract inhibited quorum sensing-regulated phenotypes in Pseudomonas aeruginosa PA01, including expression of lecA::lux (by hexane extract, swarming (maximum inhibition by methanol extract, pyocyanin (maximum inhibition by hexane extract. This study shows that the presence of natural compounds that exhibit anti-quorum sensing activity in the clove extracts may be useful as the lead of anti-infective drugs.

Solvent and electronic effects on kinetics of cyclization of thermolabile aryllithium reagents. A comparison between 1-bromo-2-(2-bromoethylbenzene and 4,5-dimethoxy-1-bromo-2-(2-bromoethylbenzene

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David A. Hunt

2009-05-01

Full Text Available A dramatic solvent effect on the stability and kinetics of intramolecular cyclization is described for the aryllithium species generated from 2-bromo-4,5-dimethoxy-(2-bromoethylbenzene. The aryllithium generated by the halogen-metal exchange reaction with n-butyllithium, is stable for > 1h when generated at -95 to -100 oC in diethyl ether/hexane and can be trapped with electrophiles. However, when the reaction is conducted in a THF/hexane mixture, the intermediate undergoes instantaneous intramolecular cyclization to afford 4,5-dimethoxybenzocyclobutene. By comparison, the corresponding 1-lithio-2-(2-bromoethyl-benzene intermediate is stable for >1h in either THF/hexane or diethyl ether/hexane at -95 to -100 oC. These results indicate that substituent effects as well as the nature of aggregation of these intermediates play key roles in determining the reaction pathway of functionalized aryllithium intermediates when quenched with electrophiles.

Laboratory Evaluations of the Fractions Efficacy of Annona senegalensis (Annonaceae) Leaf Extract on Immature Stage Development of Malarial and Filarial Mosquito Vectors.

Science.gov (United States)

Lame, Younoussa; Nukenine, Elias Nchiwan; Pierre, Danga Yinyang Simon; Elijah, Ajaegbu Eze; Esimone, Charles Okechukwu

2015-12-01

Within the framework to control mosquitoes, ovicidal, larvicidal and pupicidal activity of Annona senegalensis leaf extract and its 4 fractions against Anopheles gambiae and Culex quinquefasciatus were evaluated in the laboratory conditions. Ovicidal test was performed by submitting at least 100 eggs of mosquitoes to 125, 250, 500, 1000 and 2000 ppm concentrations, while larvicidal and pupicidal effects were assessed by submitting 25 larvae or pupae to the concentrations of 2500, 1250, 625 and 312.5 ppm of plant extract or fractions of A. senegalensis. The eggs of An. gambiae were most affected by N-hexane (0.00% hatchability) and chloroform (03.67% hatchability) fractions compared to Cx. quinquefasciatus where at least 25 % hatchability were recorded at 2000 ppm. For larvicidal test, N-hexane (LC50= 298.8 ppm) and chloroform (LC50= 418.3 ppm) fractions were more effective than other fractions on An. gambiae larvae while, a moderate effectiveness was also observed with N-hexane (LC50= 2087.6 ppm), chloroform (LC50= 9010.1 ppm) fractions on Cx. quinquefasciatus larvae. The highest mortality percent of the pupae were also recorded with N-hexane and chloroform fractions on An. gambiae at 2500 ppm. As for Cx. quinquefasciatus only 50 % and 36 % mortality were recorded with N-hexane and chloroform fractions respectively. The extract of A. senegalensis was toxic on immature stage of mosquito species tested. By splitting methanolic crude extract, only N-hexane and chloroform fractions were revealed to possess a mosquitocidal effects and could be considered and utilized for future immature mosquito vectors control.

The EED [Emergencies Engineering Division] solvent extraction process for the removal of petroleum-derived hydrocarbons from soil

International Nuclear Information System (INIS)

Bastien, C.Y.

1994-03-01

Research was conducted to investigate the ability of hexane and natural gas condensate (NGC) to extract three different types of hydrocarbon contaminant (light crude oil, diesel fuel, and bunker C oil) from three types of soil (sand, peat, and clay). A separate but related study determined the efficiency of solvent extraction (using hexane and five other solvents but not NGC) for removal of polychlorinated biphenyls (PCB) from contaminated soil. The process developed for this research includes stages of mixing, extraction, separation, and solvent recovery, for eventual implementation as a mobile solvent extraction unit. In experiments on samples created in the laboratory, extraction efficiencies of hydrocarbons often rose above 95%. On samples from a petroleum contaminated site, average extraction efficiency was ca 82%. Sandy soils contaminated in the laboratory were effectively cleaned of all hydrocarbons tested but only diesel fuel was successfully extracted from peat soils. No significant differences were observed in the effectiveness of hexane and NGC for contamination levels above 3%. Below this number, NGC seems more effective at removing oil from peat while hexane is slightly more effective on clay soils. Sand is equally cleaned by both solvents at all contamination levels. Safety considerations, odor, extra care needed to deal with light ends and aromatics, and the fact that only 26% of the solvent is actually usable make NGC an unfeasible option in spite of its significantly lower cost compared to hexane. For extracting PCBs, a hexane/acetone mixture proved to have the best removal efficiency. 14 refs., 14 figs., 7 tabs

HIDROLISIS ENZIMATIK MINYAK IKAN UNTUK PRODUKSI ASAM LEMAK OMEGA-3 MENGGUNAKAN LIPASE DARI Aspergillus niger [Enzymatic Hydrolysis of Fish Oil for Production of Omega-3 Fatty Acids Using Lipase Derived from Aspergillus niger

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Sapta Raharja*

2011-06-01

Full Text Available Fish oil is the source of important fatty-acid, especially polyunsaturated fatty acid (PUFA omega-3, such as eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA. Lipase catalysis activity of Aspergillus niger is low when it is used in fish oil hydrolysis. The activity of the lipase can be increased by adding organic solvent such as hexane into the media. This research aimed to determine temperature, pH and amount of water which produce the highest degree of hydrolysis of fish oil in the presence of hexane. Correlation between the highest degree of hydrolysis and the amount of omega-3 fatty acid was also investigated. The variables used in this research were temperatures (25-65 oC, pH (5-9, and water addition (1-5 %v/v. The highest degree of enzymatic hydrolysis of fish oil in the media without hexane was 28.07 % that was reached at 45oC and pH 5. In the presence of hexane, the highest degree of hydrolysis was 75.12 % which was reached at 5% water addition, temperature 45oC, and pH 5. GC-MS analysis showed that omega-3 fatty acid content especially EPA and DHA increased along with increase in the degree of hydrolysis. Concentration of omega-3 fatty acid produced without hexane addition was 18.42 % with EPA amounted to 12,17% and DHA 0,86%. Meanwhile omega-3 fatty acid content in the presence of hexane reached 21.93 % with EPA amounted to 17.75 % and DHA 1.21 %.

40 CFR 799.2155 - Commercial hexane.

Science.gov (United States)

2010-07-01

... study plans before this testing begins. (c) Health effects testing—(1) Subchronic inhalation toxicity—(i... provisions also apply: (1) High dose level. Unless limited by the physical/chemical nature or biological... provisions also apply: (i) Cell growth and maintenance. Appropriate culture media and incubation conditions...

2-Vinylpyridine–tris(pentafluorophenylborane hexane monosolvate

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Marcus Klahn

2012-04-01

Full Text Available The title compound, C7H7N·B(C6F53·C6H14, was obtained by the stoichiometric reaction of 2-vinylpyridine and tris(pentafluorophenylborane in toluene. The formed adduct exhibits a restricted rotation along the B—N bond resulting in an asymmetry, which can be also observed in the 19F NMR spectra. The B—N distance is equivalent to the distances found for 2-methylpyridine and 2-ethylpyridine B(C6F53 adducts. For the final refinement, the contributions of disordered solvent molecules were removed from the diffraction data with SQUEEZE in PLATON [van der Sluis & Spek (1990. Acta Cryst. A46, 194–201; Spek (2009. Acta Cryst. D65, 148–155].

Uji Fitokimia, Toksisitas dan Aktivitas Antioksidan Fraksi n-heksan dan Etil Asetat terhadap Ekstrak Jahe Merah (Zingiber officinale var. amarum

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Alpina Nora Kaban

2016-11-01

Full Text Available Has conducted research on the phytochemical test, toxicity test and test the antioxidant activity of the fraction of n-hexane and ethyl acetate to extract red ginger (Zingiber officinale amarum var.. The dried leaves weighing 382 grams, was macerated using methanol, filtered and concentrated by rotary evaporator. Then the total extract of red ginger in fractionation with n-hexane and ethyl acetate. Based on the test results of secondary metabolites phytochemical extracts of total red ginger (Zingiber officinale var amarum. Are alkaloids, flavonoids, triterpenoids and phenolic. N-hexane fraction contains alkaloids, flavonoids, steroids, triterpenoids and phenolic. Ethyl acetate fractions contain alkaloids, flavonoids, triterpenoids and phenolic. Toxicity test showed the mortality rate of shrimp larvae Artemia salina Leach using Probit Analysis SAS (Statistical Analysis System to determine the value of 50% Lethal Concentration (LC50, showed that the fraction of n-hexane toxicity with LC50 values of 63.8130 ppm; extracts of total was 71.0121 ppm and ethyl acetate was 3821.89 ppm. Test the antioxidant activity using DPPH free radical reduction in the spectrophotometer and IC50 values obtained on a total extract was 32.19 ppm; n-hexane was fraction 35.63 ppm; and ethyl acetate fraction was 25.69 ppm.

Cytotoxicity and Antiproliferative Activity Assay of Clove Mistletoe (Dendrophthoe pentandra (L. Miq. Leaves Extracts

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Vida Elsyana

2016-01-01

Full Text Available Clove mistletoe (Dendrophthoe pentandra (L. Miq. is a semiparasitic plant that belongs to Loranthaceae family. Clove mistletoe was traditionally used for cancer treatment in Indonesia. In the present study, we examined cytotoxicity of clove mistletoe leaves extracts against brine shrimps and conducted their antiproliferative activity on K562 (human chronic myelogenous leukemia and MCM-B2 (canine benign mixed mammary cancer cell lines in vitro. The tested samples were water extract, ethanol extract, ethanol fraction, ethyl acetate fraction, and n-hexane fraction. Cytotoxicity was screened using Brine Shrimp Lethality Test (BSLT. Antiproliferative activity was conducted using Trypan Blue Dye Method and cells were counted using haemocytometer. The results showed that n-hexane fraction exhibited significant cytotoxicity with LC50 value of 55.31 μg/mL. The n-hexane fraction was then considered for further examination. The n-hexane fraction of clove mistletoe could inhibit growth of K562 and MCM-B2 cancer cell lines in vitro. The inhibition activity of clove mistletoe n-hexane fraction at concentration of 125 μg/mL on K562 cancer cell lines was 38.69%, while on MCM-B2 it was 41.5%. Therefore, it was suggested that clove mistletoe had potential natural anticancer activity.

LIPID METHODOLOGY AND POLLUTANT NORMALIZATION RELATIONSHIPS FOR NEUTRAL NONPOLAR ORGANIC POLLUTANTS

Science.gov (United States)

This work compares the ability of hexane and chloroform with methanol (C/M) to extract lipid, polychlorinated biphenyls (PCBs), and p,p'-DDE from white croaker (Geneonus lineatus) muscle tissue. Hexane extracted on average 25% of the lipid and 73% of the PCB congeners that were e...

Biodiesel production from wet municipal sludge: evaluation of in situ transesterification using xylene as a cosolvent.

Science.gov (United States)

Choi, O K; Song, J S; Cha, D K; Lee, J W

2014-08-01

This study proposes a method to produce biodiesel from wet wastewater sludge. Xylene was used as an alternative cosolvent to hexane for transesterification in order to enhance the biodiesel yield from wet wastewater sludge. The water present in the sludge could be separated during transesterification by employing xylene, which has a higher boiling point than water. Xylene enhanced the biodiesel yield up to 8.12%, which was 2.5 times higher than hexane. It was comparable to the maximum biodiesel yield of 9.68% obtained from dried sludge. Xylene could reduce either the reaction time or methanol consumption, when compared to hexane for a similar yield. The fatty acid methyl esters (FAMEs) content of the biodiesel increased approximately two fold by changing the cosolvent from hexane to xylene. The transesterification method using xylene as a cosolvent can be applied effectively and economically for biodiesel recovery from wet wastewater sludge without drying process. Copyright © 2014 Elsevier Ltd. All rights reserved.

Catalytic purification of waste gases containing VOC mixtures with Ce/Zr solid solutions

Energy Technology Data Exchange (ETDEWEB)

Gutierrez-Ortiz, Jose I.; De Rivas, Beatriz; Lopez-Fonseca, Ruben; Gonzalez-Velasco, Juan R. [Chemical Technologies for Environmental Sustainability Group, Department of Chemical Engineering, Faculty of Science and Technology, Universidad del Pais Vasco/EHU, P.O. Box 644, E-48080 Bilbao (Spain)

2006-06-06

This study has been undertaken to investigate the efficiency of ceria, zirconia, and Ce{sub x}Zr{sub 1-x}O{sub 2} mixed oxides as catalysts for the vapour-phase destruction in air of single model VOCs (n-hexane, 1,2-dichloroethane and trichloroethylene) and non-chlorinated VOC/chlorinated VOC binary mixtures. Considering all catalyst compositions examined for the individual destruction of these compounds, activity for complete oxidation decreased in the following order: n-hexane<1,2-dichloroethanehexane oxidation (CeO{sub 2}). Concerning chlorinated VOCs conversion, it was observed that notable improvements in catalyst activity of CeO{sub 2} could be achieved through structural doping with Zr ions. Mixed oxides exhibited promoted redox and acid properties, which resulted catalytically relevant for the oxidation of 1,2-dichloroethane and trichloroethylene. In contrast, the combustion of n-hexane was essentially controlled by surface oxygen species, which were more abundant on CeO{sub 2}. Attainment of high n-hexane conversions with CeO{sub 2} was also attributed in part to the hydrophobicity of the support and the reduced interaction with carbon dioxide. Significant 'mixture effects' on both activity and selectivity were noticed when a given chlorinated feed was decomposed in the presence of n-hexane. On one hand, each VOC decreased the reactivity of the other relative to that of the pure compound resulting in higher operating temperatures to achieve adequate destruction. Competitive adsorption played an important role in the reciprocal inhibition effects detected with all catalysts. On the other hand, the selectivity to HCl was noticeably enhanced when n-hexane was co-fed, probably due to the increased presence of water generated as an

Water activity control: a way to improve the efficiency of continuous lipase esterification.

Science.gov (United States)

Colombié, S; Tweddell, R J; Condoret, J S; Marty, A

1998-11-05

During continuous lipase-catalyzed oleic acid esterification by ethanol in n-hexane, the oleic acid conversion, initially at 95%, decreases to 20% after 2 h. This decrease is caused by the accumulation of the water produced in the course of the reaction in the packed-bed reactor (PBR). In order to improve the PBR efficiency, it is necessary to evacuate the water produced. In this study, different approaches have been tested to control the water content in the PBR during continuous esterification. The first approach consisted in improving the water solubility by increasing the reaction medium polarity. The addition of polar additives to n-hexane, the use of more polar solvents, and the use of solvent-free reaction medium were tested as a means to favor the water evacuation from the PBR. First of all, the use ofn-hexane supplemented with acetone (3 M) or 2-methyl-2-propanol (1 M) enabled the conversion to be maintained at higher values than those obtained in pure n-hexane. The replacement of n-hexane by a more polar solvent, like the 5-methyl-2-hexanone, resulted in the same effect. In all cases, conversions at steady-state were always less than 95%, as obtained in pure n-hexane. This is explained by a decrease in the enzyme activity due to the increase in the medium polarity. Nevertheless, an increase in enzyme quantity allowed 90% conversion to be maintained during 1 week using 3 M acetone amended n-hexane. Good results (a steady-state conversion of about 80%) were obtained when esterification was carried out in a solvent-free reaction medium containing 2 M 2-methyl-2-propanol as a polar additive. The second approach consisted in the evaporation of the accumulated water by use of an intermittent airflow. Although this process did not enable constant esterification rate to be maintained, it did enable the initial conversion (95%) to be restored intermittently. Copyright 1998 John Wiley & Sons, Inc.

Biological activities of Rumex dentatus L: Evaluation of methanol ...

African Journals Online (AJOL)

The methanol extracts of leaf and stem inhibited radish seed germination (70 and 61% respectively) and root length more than the hexane extracts. The R. dentatus methanol extract showed presence of alkaloids, saponins, anthraquinones and tannins while flavonoids were also found in both methanol as well as hexane ...

IDENTIFICATION OF THE ISOLATED COMPOUNDS FROM Zingiber amaricans BL. RHIZOME

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Sugeng Riyanto

2010-06-01

Full Text Available Five extracts were obtained from extraction of rhizomes of Zingiber amaricans. Hexane, dichloromethane and methanol extracts were obtained by maceration, while dichloromethane and acetone extracts the resulted of soxhlet extraction. By column chromatography technique 2,6,9-humulantrien-9-one (zerumbone was isolated as the major constituent of the hexane, dichloromethane and methanol extracts. The minor constituents were phytosterol mixtures isolated from hexane and dichloromethane extracts. The mixtures consisted cholesterol, campesterol, stigmasterol and b-sitosterol. The structure elucidations of zerumbone was confirmed by spectroscopic method, whereas the phytosterol mixtures was identified by gas chromatography-mass.   Keywords: zerumbone, phytosterol, zingiber amaricans, spectroscopy

Volatile and non-volatile compounds and antimicrobial activity of Mansoa difficilis (Cham.) Bureau and K. Schum. (Bignoniaceae)

International Nuclear Information System (INIS)

Guilhon, Giselle Maria Skelding Pinheiro; Silva, Elisangela Sarmento da; Santos, Lourivaldo da Silva; Uetanabaro, Ana Paula Trovatti

2012-01-01

Essential oil from the leaves of Mansoa difficilis was analyzed by GC/MS. Oct-1-en-3-ol (49.65%) was the major compound, but diallyl di- and trisulfide were also present (0.85 and 0.37%, respectively), justifying the garlic-like odor of the crushed leaves. The hexane and methanol extracts of the leaves and stems afforded as main constituents a mixture of linear hydrocarbons, spinasterol, stigmasterol, ursolic and oleanolic acids, two apigenin derivatives and verbascoside. The hexane and methanol extracts of leaves were tested for antimicrobial activity against ten microorganisms. The hexane extract was active against both Pseudomonas aeruginosa and Staphylococcus aureus. (author)

Volatile and non-volatile compounds and antimicrobial activity of Mansoa difficilis (Cham.) Bureau and K. Schum. (Bignoniaceae)

Energy Technology Data Exchange (ETDEWEB)

Guilhon, Giselle Maria Skelding Pinheiro; Silva, Elisangela Sarmento da; Santos, Lourivaldo da Silva [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Fac. de Quimica; Zoghbi, Maria das Gracas Bichara [Museu Paraense Emilio Goeldi, Belem, PA (Brazil). Coordenacao de Botanica; Araujo, Isabella Santos [Universidade Estadual de Feira de Santana (UEFS), Feira de Santana, BA (Brazil); Uetanabaro, Ana Paula Trovatti, E-mail: giselle@ufpa.br [Universidade Estadual de Santa Cruz (UESC), Ilheus, BA (Brazil)

2012-07-01

Essential oil from the leaves of Mansoa difficilis was analyzed by GC/MS. Oct-1-en-3-ol (49.65%) was the major compound, but diallyl di- and trisulfide were also present (0.85 and 0.37%, respectively), justifying the garlic-like odor of the crushed leaves. The hexane and methanol extracts of the leaves and stems afforded as main constituents a mixture of linear hydrocarbons, spinasterol, stigmasterol, ursolic and oleanolic acids, two apigenin derivatives and verbascoside. The hexane and methanol extracts of leaves were tested for antimicrobial activity against ten microorganisms. The hexane extract was active against both Pseudomonas aeruginosa and Staphylococcus aureus. (author)

JCSC_128_11_1703_1707_SI_a.docx

Indian Academy of Sciences (India)

dell

Finally, the reaction was neutralized by triethyl ammine and the solution passed through a small basic alumina column. The reaction mixture was concentrated and 8 was separated by silica gel column chromatography using DCM/Hexane as eluent. 8 was crystallised with DCM/Hexane system. [8]2+ was generated by ...

Fulltext PDF

Indian Academy of Sciences (India)

(PPARs) agonists in particular in the management of hyperglycemia and hyperlipidaemia for the treatment of. Type 2 Diabetes (T2D). We have .... under reduced pressure to give a residue which upon trituration with hexane or upon column chromatography (hexane/EtOAc, 1:5) gave the desired compound as a solid.

Physicochemical and microbiological characterization of linolenic ...

African Journals Online (AJOL)

SWEET

2012-05-15

May 15, 2012 ... absorbance of hexanic oil solution (1%) by using a UV-Vis .... two fairly stacking graphs with maximum absorbances at. 220 and 280 nm ... extracted oilseeds of the two plants were fungus, ... triplicate by measuring absorbances of hexanic oilseeds (1%) in the wavelengths range varying from 200 to 600 nm.

Evaluation of different tissue de-paraffinization procedures for infrared spectral imaging.

Science.gov (United States)

Nallala, Jayakrupakar; Lloyd, Gavin Rhys; Stone, Nicholas

2015-04-07

In infrared spectral histopathology, paraffin embedded tissues are often de-paraffinized using chemical agents such as xylene and hexane. These chemicals are known to be toxic and the routine de-waxing procedure is time consuming. A comparative study was carried out to identify alternate de-paraffinization methods by using paraffin oil and electronic de-paraffinization (using a mathematical computer algorithm) and their effectiveness was compared to xylene and hexane. Sixteen adjacent tissue sections obtained from a single block of a normal colon tissue were de-paraffinized using xylene, hexane and paraffin oil (+ hexane wash) at five different time points each for comparison. One section was reserved unprocessed for electronic de-paraffinization based on a modified extended multiplicative signal correction (EMSC). IR imaging was carried out on these tissue sections. Coefficients based on the fit of a pure paraffin model to the IR images were then calculated to estimate the amount of paraffin remaining after processing. Results indicate that on average xylene removes more paraffin in comparison to hexane and paraffin oil although the differences were small. This makes paraffin oil, followed by a hexane wash, an interesting and less toxic alternative method of de-paraffinization. However, none of the chemical methods removed paraffin completely from the tissues at any given time point. Moreover, paraffin was removed more easily from the glandular regions than the connective tissue regions indicating a form of differential paraffin retention based on the histology. In such cases, the use of electronic de-paraffinization to neutralize such variances across different tissue regions might be considered. Moreover it is faster, reduces scatter artefacts by index matching and enables samples to be easily stored for further analysis if required.

ISOLASI DAN IDENTIFIKASI ARTEMISININ DARI HERBA Artemisia annua L .

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Sukmayati Alegantina

2012-07-01

Full Text Available Abstract. Malaria is still a major problem in Indonesia, because mortality in patients with severe malaria remains high. Many cases are occurs in endemic areas (e.g. Papua,Kalimantan, Bali and Sulawesi. Chloroquin is the most common antimalarial drug which is widely used since 1934. Plasmodium falciparum resistant to chloroquine was reported in some countries (e.g. Thailand, Vietnam, Indonesia, and Bangladesh. To delay the development of resistance, WHO recommended antimalarial combination therapy. Artemisinin and its derivatives (artesunate, artemether, dihydroartemisin produce rapid clearance of parasitemia and rapid resolution of symptoms compare with chloroquine. Artemisinin is obtained from Artemisia annua L. Even though there are some research produced a chemical synthetic of artemisinin, but it is not efficient and notstable. Our purposes are to conduct a preliminary research to obtain a method of isolation and identification of artemisinin which is the first step to develop a raw material of artemisinin as antimalarial drug in Indonesia.The first step of isolation is extraction from herb Artemisia annua L with n-hexane thatproduced n-hexane extract, this process is well-known as soxhletation. The second step isidentification of chemical substances from n-hexane extract. The third step is to obtain isolate from n-hexane extract by fractionation with acetonitril and separation with column chromatography. The last step is chemical and physical identification of isolateby TLC (Thin Layer (Chromatography and FT-IR.The result from n-hexane extract measurement is 4.33 % and from acetonitril fraction is2. 40 %. Chemical identification of n-hexan extract found there are terpenoid, phenol, flavonoid, fatty acid, atsiri oil and saponin. Organoleptic identification of isolate is white crystal, monosubstrate, odorless and bitter. Identification of isolate with TLC and FT-IR confirmed that the isolate is artemisinin.Keywords: artemisinin, Artemisia

Conversion of potash soap and lignin into liquid fuels. Final report; Suovan ja ligniinin jalostaminen polttonesteiksi. Loppuraportti

Energy Technology Data Exchange (ETDEWEB)

McKeough, P.; Oasmaa, A.

1994-12-31

The main task of the research is to estimate the suitability of catalytic hydration for refining of following rawmaterials into liquid fuels: concentrated black liquor, raw potash soap (especially birch containing mixed potash soap) and organosolv (Milox) lignin. When hydrating the concentrated black liquor catalytically (ammonium heptamolybdate/420 deg C or NiMo-Cr{sub 2}O{sub 3}/450 deg C) it is possible to convert about 30 wt-% of the original organic matter of the black liquor into hexane soluble oils. It is possible to remove the inorganic matter from the product oil by water extraction without reducing the amount of hexane suluble oil. The energy content of the hexane soluble oil is about 60 % of the energy content of the black liquor. The raw potash soap is cracked into oils and gases at 435- 450 deg C. The yield of the hexane soluble oil in nitrogen atmosphere without a catalyst is about 40 % of the organic matter of the potash soap. The calorific value of the oil is 42 MJ/kg, which corresponds to about 45 % energy yield. The presence of a catalyst and hydrogen gas increases the yield of hexane soluble oil (45 wt-%) and effects on the chemical composition of the product by increasing the portion of aliphatic hydrocarbons. It is possible to obtain oil of good quality from Milox lignin by using the catalytic hydration. At 420 deg C with 60 min retention time, at presence of the NiMo- Cr{sub 2}O{sub 3} catalyst and hydrogen gas, oil yield of 53 % and hexane soluble oil yield of 41 % (of organic matter of lignin) are obtained. The calorific value of the oil is 40 MJ/kg (Milox lignin 25 MJ/kg). (3 refs., 3 tabs., 1 fig.)

A new ester coumarin from Ferula Persica wild, indigenous to Iran.

Science.gov (United States)

Razavi, Seyed Mehdi; Janani, Mehrnoush

2015-01-01

Ferula persica wild (Apiaceae) is a perennial herb indigenous to Iran. It has been used in folk medicine for treatment of diabetes, lowering of blood pressure and for antispasmodic, carminative, laxative and expectorant effects in central Iran. Dried ground roots of F. persica (150 g) were extracted sequentially with n-hexane, dichloromethane and methanol (MeOH), 500 ml each, using a Soxhlet apparatus. The n-hexane extract of the roots (3 g) was subjected to vacuum liquid chromatography on silica gel, eluting with solvent mixtures of increasing polarity: 100% n-hexane-ethyl acetate (EtOAc), to yield a number of fractions, Fraction 4 (80% EtOAc in n-hexane) was further analysed by preparative TLC (mobile phase was 12% acetone in chloroform) to yield a coumarin ester (10.1 mg, Rf = 0.31, blue florescent). The structure of the isolated compound was elucidated by spectroscopic means. The compound is 7-O-(4,8,12 -trihydroxy-4,8,12-trimethyl-tridecanoyl)-coumarin, named, ferulone C as a new natural product.

Evaluation of food grade solvents for lipid extraction and impact of storage temperature on fatty acid composition of edible seaweeds Laminaria digitata (Phaeophyceae) and Palmaria palmata (Rhodophyta).

Science.gov (United States)

Schmid, Matthias; Guihéneuf, Freddy; Stengel, Dagmar B

2016-10-01

This study evaluated the impact of different food- and non-food grade extraction solvents on yield and fatty acid composition of the lipid extracts of two seaweed species (Palmaria palmata and Laminaria digitata). The application of chloroform/methanol and three different food grade solvents (ethanol, hexane, ethanol/hexane) revealed significant differences in both, extraction yield and fatty acid composition. The extraction efficiency, in terms of yields of total fatty acids (TFA), was in the order: chloroform/methanol>ethanol>hexane>ethanol/hexane for both species. Highest levels of polyunsaturated fatty acids (PUFA) were achieved by the extraction with ethanol. Additionally the effect of storage temperature on the stability of PUFA in ground and freeze-dried seaweed biomass was investigated. Seaweed samples were stored for a total duration of 22months at three different temperatures (-20°C, 4°C and 20°C). Levels of TFA and PUFA were only stable after storage at -20°C for the two seaweed species. Copyright © 2016 Elsevier Ltd. All rights reserved.

Interfacial behavior of alkaline protease at the air-water and oil-water interfaces

Science.gov (United States)

Zhang, Jian; Li, Yanyan; Wang, Jing; Zhang, Yue

2018-03-01

The interfacial behavior of alkaline protease at the air-water and n-hexane-water interfaces was investigated using interfacial tension, dilatational rheology and dynamic light scattering. Additionally, different adsorption models which are Langmuir, Frumkin, Reorientation-A and Reorientation-R were used to fitting the data of equilibrium interfacial tension for further understanding the interfacial behavior of alkaline protease. Data fitting of the equilibrium interfacial tension was achieved by IsoFit software. The results show that the molecules arrangement of the alkaline protease at the n-hexane-water interface is more tightly than at the air-water interface. The data were further analyzed to indicate that the hydrophobic chains of alkaline protease penetrate into oil phase deeper than the air phase. Also data indicate that the electrostatic interactions and hydrophobic interactions at the n-hexane-water interface are stronger than at the air-water interface within molecules of the alkaline protease. Based on comprehensive analysis of the adsorption kinetics and interfacial rheological properties, interfacial structures mechanism of alkaline protease at n-hexane-water and air-water interfaces was proposed.

Processing of spent nickelcatalyst for fat recovery

Directory of Open Access Journals (Sweden)

NASIR Mohammad Ibraim

2001-01-01

Full Text Available Spent nickel catalyst (SNC has the potential of insulting the quality of the environment in a number of ways. Its disposal has a pollution effect. Optimum recovery of fat from SNC, could save the environment and reduce the oil loss. Hexane has been the solvent of choice for oil extraction. Alternative solvents considered to have been safer have been evaluated. Hexane, isopropanol, ethanol and heptane were examined using soxhlet extraction. While hexane is more efficient in oil recovery from SNC, isopropanol proved to be very good in clear separation of oil from waste material and also provides high solvent recovery compared to other solvents. Isopropanol extraction with chill separation of miscella into lower oil-rich phase, and an upper, solvent-rich recyclable phase save mush energy of vaporization for distilling. An aqueous extraction process with immiscible solvent assisted was tested. Solvent like hexane added to SNC, and water added later with continuous stirring. The mixture was stirred for about 30 minutes, prior to centrifugation. Aqueous process extracted less amount of oil compared to solvent extraction.

Evaporation of a Volatile Liquid Lens on the Surface of an Immiscible Liquid.

Science.gov (United States)

Sun, Wei; Yang, Fuqian

2016-06-21

The evaporation behavior of toluene and hexane lenses on the surface of deionized (DI) water is studied. The toluene and hexane lenses during evaporation experience an advancing stage and a receding stage. There exists a significant difference of the evaporation behavior between the toluene lenses and the hexane lenses. The lifetime and largest diameter of both the toluene and hexane lenses increase with increasing the initial volume of the lenses. For the evaporation of the toluene lenses, the lifetime and largest diameter of the lenses decrease with increasing the temperature of DI water. The effect of the residual of the oil molecules on the evaporation of toluene lenses at a temperature of 21 °C is investigated via the evaporation of a series of consecutive toluene lenses being placed on the same position of the surface of DI water. The temporal evolution of the toluene lenses placed after the first toluene lens deviates significantly from that of the first toluene lens. Significant increase of the receding speed occurs at the dimensionless time in a range 0.7-0.8.

Phytochemical screening, antiproliferative and cytotoxic activities of the mosses Rhytidiadelphus triquetrus (Hedw. Warnst. and Tortella tortuosa (Hedw. Limpr.

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Muhammet Şamil Yağlıoğlu

2017-06-01

Full Text Available The paper presents information about the phytochemical analysis, antiproliferative and cytotoxic activities of Rhytidiadelphus triquetrus and Tortella tortuosa extracts. The cytotoxic activities of some extracts shows highest antiproliferative activities were detected with Lactate Dehydrogenase Leakage Assay. Sixteen components obtained from hexane extracts were determined by GC/MS. Palmitic acid was identified as the main component. The phenolic components of the other extracts were determined by HPLC-TOF/MS. 4-hydroxy benzoic acid, salicylic acid, gallic acid, caffeic acid, and gensitic acid were detected as the main components in all extracts. The hexane, chloroform, ethyl acetate extracts of studied mosses and the EtOAc and hexane extracts of R. triquetrus showed statistically significant antiproliferative activities.

Actividad antibacteriana de algunas especies medicinales de Eupatorium contra bacterias patógenas resistentes a antibióticos

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Edgar García-Sánchez

2015-07-01

Full Text Available Thirty six samples arising from hexane, dichloromethane, and methanol extracts from four medicinal Eupatorium species were screened against Gram positive and Gram negative resistant bacteria associated with nosocomial infections by disk diffusion method. The best antibacterial extracts were selected by correspondence analysis. The hexane extracts showed high inhibition against clinical isolated bacteria. The qualitative chemical analysis was realized in the best antibacterial hexane extracts. The main components identified were triterpenes and benzopyran compounds which of extensively had been reported their antibacterial activities. Our results showing that medicinal Eupatorium species studied in this work have metabolites secondary antibacterial particularly against antibiotic resistant strains, Klebsiella pneumoniae and Staphylococcus aureus and validate their uses in traditional medicine

Release of volatile mercury from vascular plants

Science.gov (United States)

Siegel, S. M.; Puerner, N. J.; Speitel, T. W.

1974-01-01

Volatile, organic solvent soluble mercury has been found in leaves and seeds of several angiosperms. Leaves of garlic vine, avocado, and haole-koa release mercury in volatile form rapidly at room temperature. In garlic vine, the most active release is temperature dependent, but does not parallel the vapor-pressure temperature relationship for mercury. Mercury can be trapped in nitric-perchloric acid digestion fluid, or n-hexane, but is lost from the hexane unless the acid mixture is present. Seeds of haole-koa also contain extractable mercury but volatility declines in the series n-hexane (90%), methanol (50%), water (10%). This suggests that reduced volatility may accompany solvolysis in the more polar media.

Adsorption competition study between oxygenated compounds and hydrocarbons on molecular sieves; Etude de la competition d`adsorption entre les composes oxygenes et les hydrocarbures sur les tamis moleculaires

Energy Technology Data Exchange (ETDEWEB)

Kong Ming, L.

1996-11-29

The aim of this study is to determine the competitive behavior of methanol and l -hexene in an n-hexane solvent system using a 13-x and a molecular sieves as the adsorbent. Adsorption was carried out in liquid phase. Parameters such as concentration, flowrate, temperature and column, length were varied in order to assess their effects on the breakthrough curves. In methanol-n-hexane system, it was found that the concentration profiles of the breakthrough curves were not very much influenced by the parameters except for the amount of volume of feed processes. However, changes in the flowrate does not have a significant effect on the concentration profile. A higher flowrate, the profile assumes a more dispersive pattern which of course is expected due to lower contact time if internal diffusion is rate determining. In the case of l -hexane carries out at different temperatures and column lengths there were some differences in concentration profiles. This may be due to experimental difficulties in controlling the flowrate at the start of the experiment rather than inherent adsorption behavior. In the 3-component system, 1 -hexene breakthrough was very much earlier as compared to methanol. Desorption carried out at 383 k and with flowrate of 28{+-}l g/min and for 100 minutes for all cases showed little variation. Re-adsorption under various conditions showed marked reduction in the amount of feed processed. The breakthrough curves were simulated using an Institut Francais du Petrole (IFP) proprietary computer program which is based on selectivity and theoretical plates and which predicts very well for xylene separation. In the 1 -hexene-n-hexane system, the simulator predicted reasonably well in terms of bed volume processed, however, for the methanol-n-hexane system the simulator failed. For the program to be effective, some mathematical treatments needs to be done with respect to the handling of the numerical analysis. To describe the adsorption equilibrium, two

Highly Solvent Tolerance in Serratia marcescens IBBPo15

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Mihaela Marilena Stancu

Full Text Available ABSTRACT The aim of this study was to investigate the solvent tolerance mechanisms in Serratia marcescens strain IBBPo15 (KT315653. Serratia marcescens IBBPo15 exhibited remarkable solvent-tolerance, being able to survive in the presence of high concentrations (above 40% of toxic organic solvents, such as cyclohexane, n-hexane, n-decane, toluene, styrene, and ethylbenzene. S. marcescens IBBPo15 produced extracellular protease and the enzyme production decreased in cells exposed to 5% cyclohexane, n-hexane, toluene, styrene, and ethylbenzene, as compared with the control and n-decane exposed cells. S. marcescens IBBPo15 cells produced carotenoid pigments and alteration of pigments profile (i.e., phytoene, lycopene were observed in cells exposed to 5% cyclohexane, n-hexane, n-decane, toluene, styrene, and ethylbenzene. The exposure of S. marcescens IBBPo15 cells to 5% cyclohexane, n-hexane, n-decane, toluene, styrene, ethylbenzene induced also changes in the intracellular (e.g., 50 kDa protein and extracellular (e.g., 39, 41, 43, 53, 110 kDa proteins proteins profile. Significant RAPD, ARDRA, rep-PCR and PCR pattern modifications were not observed in DNA extracted from S. marcescens IBBPo15 cells exposed to 5% cyclohexane, n-hexane, n-decane, toluene, styrene, and ethylbenzene. Though only HAE1 and acrAB genes were detected in the genome of S. marcescens IBBPo15 cells, the unspecific amplification of other fragments being observed also when the primers for ompF and recA genes were used.

Genotoxic and cytotoxic potential of whole plant extracts of Kalanchoe laciniata by Ames and MTT assay.

Science.gov (United States)

Sharif, Ali; Akhtar, Muhammad Furqan; Akhtar, Bushra; Saleem, Ammara; Manan, Maria; Shabbir, Maryam; Ashraf, Muneeb; Peerzada, Sohaib; Ahmed, Shoaib; Raza, Moosa

2017-01-01

Lack of data on safety of herbal medicines have endangered human health and life. The present study evaluated the genotoxic and mutagenic effect of Kalanchoe laciniata to access the safety and usefulness of the medicinal plant. Aqua-methanolic and n-hexane extracts of K. laciniata were evaluated for the genotoxic potential using Ames assay and cytotoxicity was evaluated using MTT assay. Ames assay was conducted using two strains of Salmonella typhimurium TA-100 and TA-102 whereas MTT assay was performed on baby hamster kidney cell line BHK-21. Aqua-methanolic extract of K. laciniata exhibited significant mutagenicity when exposed to TA-102 strain with a mutagenic index of 50.66 and 54.74 at maximum dose 150 mg/plate. The extract was also mutagenic to TA-100 strain but to a lesser extent. M.I of n-hexane extract was 12.15 and 15.51 for TA-100 and TA-102 respectively. n-hexane extract was mutagenic but little difference was observed between results of two strains. Both extracts were found to be cytotoxic with an IC 50 of 321.9 and 638.5 µg/mL for aqua-methanolic and n-hexane extracts respectively. On the basis of results it was concluded that aqua-methanolic and n-hexane extracts of K. laciniata possess mutagenic and cytotoxic potential. It is suggested to explore the plant further to evaluate its safety in rodents and other species.

Reducing post-harvest losses in South Asia's mango orchards ...

International Development Research Centre (IDRC) Digital Library (Canada)

2016-04-29

Apr 29, 2016 ... Spraying a small concentration of hexanal in mango orchards has been found to delay the ripening of the fruit by an extra three weeks, enabling farmers to earn up to 15% more for their crop. Once the crop is harvested, hexanal-sprayed mangoes also have a much longer shelf life—up to 26 days in cold ...

Preliminary evaluation of anhydrous ethanol as a solvent in the oilseed extraction of Jatropha curcas L.; Evaluacion preliminar del etanol anhidro como solvente en la extraccion de aceite de semillas de jatrofa (Jatropha curcas L.)

Energy Technology Data Exchange (ETDEWEB)

Brossard-Gonzalez, C.; Ferrari, R. A.; Pighinelli, A. L.; Park, K. J.

2010-07-01

A preliminary evaluation was performed on anhydrous ethanol as a solvent for the extraction of oil from whole Jatropha curcas L. seeds (32.24 % lipids, 16.05 % proteins), supplied from Mato Grosso, Brazil. The methodology of factorial 2k designs was followed, which included a comparison between pressing and n-hexane extraction methods. The regression model corresponding to the comparison between ethanol and n-hexane, varying extraction time, did not have lack of fit and presented an R2 of 99%. The experimental design for the pressing method, varying press rotation speed and temperature, yielded a poorly fitted linear model. The oil composition extracted with ethanol was similar to those obtained by n-hexane and by pressing. The highest yield (36.7%) was obtained using ethanol for 4 hours. The excess of extracted material was attributed to additional solubilization of impurities that could be diminished by limiting the extraction time to 1 hour. The oil extracted with ethanol and by pressing have the same color. It is presumed that the purification steps for both oils should be similar. Further studies using mixtures of ethanol with small proportions of n-hexane are suggested. (Author) 20 refs.

Radiolysis of triphenylarsine in a mixture of benzene and cyclohexane. [. gamma. radiation

Energy Technology Data Exchange (ETDEWEB)

Nazir, S B; Rai, R S [Birla Inst. of Tech. and Science, Pilani (India). Dept. of Chemistry

1975-06-01

A number of degassed samples of triphenylarsine were irradiated by gamma radiation in a mixture of benzene and cyclohexane. The condensable products formed were pentane, hexane, benzene and cyclohexane in cyclohexane solution containing triphenylarsine and cyclohexane in benzene in presence of triphenylarsine. When the composition of the solvent was varried by stepwise addition of benzene from 5 to 50%, the main condensable radiolytic products observed by vapour phase chromatography were hexane, : hexane and cyclohexene. No pentane was observed when benzene was present in the mixture upto 15%. However, it was detected in the presence of 20-30% benzene mixture. When the amount of benzene was 35-50% in the mixture, two isomers of hexane and hexene were also detected. A mechanism has been worked out for the formation of these compounds and protection and sensitization mechanisms have been invoked to explain the yields per 100 ev. From the kinetic analysis, it has been found out that the rate of formation of cyclohexene is much faster than rates of different products formed during gamma radiolysis and from the analysis of experimental data, sponge type protection has been postulated in this radiolytic system.

Improvement of biogas production from orange peel waste by leaching of limonene.

Science.gov (United States)

Wikandari, Rachma; Nguyen, Huong; Millati, Ria; Niklasson, Claes; Taherzadeh, Mohammad J

2015-01-01

Limonene is present in orange peel wastes and is known as an antimicrobial agent, which impedes biogas production when digesting the peels. In this work, pretreatment of the peels to remove limonene under mild condition was proposed by leaching of limonene using hexane as solvent. The pretreatments were carried out with homogenized or chopped orange peel at 20-40°C with orange peel waste and hexane ratio (w/v) ranging from 1 : 2 to 1 : 12 for 10 to 300 min. The pretreated peels were then digested in batch reactors for 33 days. The highest biogas production was achieved by treating chopped orange peel waste and hexane ratio of 12 : 1 at 20°C for 10 min corresponding to more than threefold increase of biogas production from 0.061 to 0.217 m(3) methane/kg VS. The solvent recovery was 90% using vacuum filtration and needs further separation using evaporation. The hexane residue in the peel had a negative impact on biogas production as shown by 28.6% reduction of methane and lower methane production of pretreated orange peel waste in semicontinuous digestion system compared to that of untreated peel.

Improving carotenoid extraction from tomato waste by pulsed electric fields.

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Elisa eLuengo

2014-08-01

Full Text Available In this investigation, the influence of the application of Pulsed Electric Fields (PEF of different intensities (3-7 kV/cm and 0-300 μs on the carotenoid extraction from tomato peel and pulp in a mixture of hexane:acetone:ethanol was studied with the aim of increasing extraction yield or reducing the percentage of the less green solvents in the extraction medium. According to the cellular disintegration index, the optimum treatment time for the permeabilization of tomato peel and pulp at different electric field strengths was 90 µs. The PEF permeabilization of tomato pulp did not significantly increase the carotenoid extraction. However, a PEF-treatment at 5 kV/cm improved the carotenoid extraction from tomato peel by 39 % as compared with the control in a mixture of hexane:ethanol:acetone (50:25:25. Further increments of electric field from 5 to 7 kV/cm did not increase significantly the extraction of carotenoids. . The presence of acetone in the solvent mixture did not positively affect the carotenoid extraction when the tomato peels were PEF-treated. Response surface methodology was used to determine the potential of PEF for reducing the percentage of hexane in a hexane:ethanol mixture. The application of a PEF-treatment allowed reducing the hexane percentage from 45 to 30 % without affecting the carotenoid extraction yield. The antioxidant capacity of the extracts obtained from tomato peel was correlated with the carotenoid concentration and it was not affected by the PEF-treatment.

Separation of different ion structures in atmospheric pressure photoionization-ion mobility spectrometry-mass spectrometry (APPI-IMS-MS).

Science.gov (United States)

Laakia, Jaakko; Adamov, Alexey; Jussila, Matti; Pedersen, Christian S; Sysoev, Alexey A; Kotiaho, Tapio

2010-09-01

This study demonstrates how positive ion atmospheric pressure photoionization-ion mobility spectrometry-mass spectrometry (APPI-IMS-MS) can be used to produce different ionic forms of an analyte and how these can be separated. When hexane:toluene (9:1) is used as a solvent, 2,6-di-tert-butylpyridine (2,6-DtBPyr) and 2,6-di-tert-4-methylpyridine (2,6-DtB-4-MPyr) efficiently produce radical cations [M](+*) and protonated [M + H](+) molecules, whereas, when the sample solvent is hexane, protonated molecules are mainly formed. Interestingly, radical cations drift slower in the drift tube than the protonated molecules. It was observed that an oxygen adduct ion, [M + O(2)](+*), which was clearly seen in the mass spectra for hexane:toluene (9:1) solutions, shares the same mobility with radical cations, [M](+*). Therefore, the observed mobility order is most likely explained by oxygen adduct formation, i.e., the radical cation forming a heavier adduct. For pyridine and 2-tert-butylpyridine, only protonated molecules could be efficiently formed in the conditions used. For 1- and 2-naphthol it was observed that in hexane the protonated molecule typically had a higher intensity than the radical cation, whereas in hexane:toluene (9:1) the radical cation [M](+*) typically had a higher intensity than the protonated molecule [M + H](+). Interestingly, the latter drifts slower than the radical cation [M](+*), which is the opposite of the drift pattern seen for 2,6-DtBPyr and 2,6-DtB-4-MPyr. 2010 American Society for Mass Spectrometry. Published by Elsevier Inc. All rights reserved.

Laboratory Evaluations of the Fractions Efficacy of Annona senegalensis (Annonaceae Leaf Extract on Immature Stage Development of Malarial and Filarial Mosquito Vectors

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Younoussa Lame

2015-10-01

Full Text Available Background: Within the framework to control mosquitoes, ovicidal, larvicidal and pupicidal activity of Annona senegalensis leaf extract and its 4 fractions against Anopheles gambiae and Culex quinquefasciatus were evaluated in the laboratory conditions.Methods: Ovicidal test was performed by submitting at least 100 eggs of mosquitoes to 125, 250, 500, 1000 and 2000 ppm concentrations, while larvicidal and pupicidal effects were assessed by submitting 25 larvae or pupae to the concentrations of 2500, 1250, 625 and 312.5 ppm of plant extract or fractions of A. senegalensis.Results: The eggs of An. gambiae were most affected by N-hexane (0.00% hatchability and chloroform (03.67% hatchability fractions compared to Cx. quinquefasciatus where at least 25 % hatchability were recorded at 2000 ppm. For larvicidal test, N-hexane (LC50= 298.8 ppm and chloroform (LC50= 418.3 ppm fractions were more effective than other fractions on An. gambiae larvae while, a moderate effectiveness was also observed with Nhexane (LC50= 2087.6 ppm, chloroform (LC50= 9010.1 ppm fractions on Cx. quinquefasciatus larvae. The highest mortality percent of the pupae were also recorded with N-hexane and chloroform fractions on An. gambiae at 2500 ppm. As for Cx. quinquefasciatus only 50 % and 36 % mortality were recorded with N-hexane and chloroform fractions respectively.Conclusion: The extract of A. senegalensis was toxic on immature stage of mosquito species tested. By splitting methanolic crude extract, only N-hexane and chloroform fractions were revealed to possess a mosquitocidal effects and could be considered and utilized for future immature mosquito vectors control.

Comparative study of the active sites in zeolites by different probe molecules

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ALINE AUROUX

2005-03-01

Full Text Available This review summarizes some of the recently published results concerning the acid sites in the zeolites ZSM-5 and Y studied by temperature-programmed desorption (TPD and adsorption calorimetry using different probe molecules NH3, CO, N2O and n-hexane. For the first time it has been shown that the acid sites in hydrated zeolites are accessible for n-hexane adsorption

Fabrication and characterization of nanocomposites reinforced by carbon nanotubes - (1) synthesis of carbon nanotubes

Energy Technology Data Exchange (ETDEWEB)

Hseuh Hsiangming; Tai Nyanhwa; Perng Tongping [Dept. of Material Science, National Tsing-Hwa Univ., TW (China); Chyou Sander [Taiwan Power Research Inst., Taiwan Power Co., Taipei (China)

2003-07-01

Multi-walled carbon nanotubes (MWCNTs) produced by floating catalyst method were used for reinforcing material in polymeric nanocomposites. Five different kinds of carbon sources (benzene, toluene, xylene, cyclo-hexane, n-hexane) were used as precursors in the thermal chemical vapor deposition process. The products were collected and examined by Raman, HRTEM, and FESEM. The differences in microstructure and morphologies among these products are analyzed and discussed. (orig.)

The uranium (VI) determination method in the technological products

International Nuclear Information System (INIS)

Fursa, L.I.; Belykevich, N.A.

1994-01-01

The method includes an extraction of the uranyl nitrate by solution' hexa butyl tries amide of phosphoric acid in the hexane, a reextraction of uranium by arsenazo III solution under pH 2 and following the solution' photometry. With the purpose of excluding the emulsion' formation under uranium reextraction has been added chloroform in volume ratio to hexane 1:(3.0-7.5). tabs. 2

Applications of Laser Diagnostics

Science.gov (United States)

2005-03-01

fraction of methane in the fuel is 0.48. The steady nozzle velocities of the fuel and oxyder stream are respectively 0.59 m/s and 0.61 m/s. The...Hexane Heptane Toluene Benzene THF Ethyl acetate Chloroform Dichloromethane Acetone DMSO Propylene carbonate Benzyl alcohol Ethanol Methanol Octanol...Cyclohexane Pentane Hexane Heptane Toluene Benzene THF Ethyl acetate Chloroform Dichloromethane Acetone DMSO Propylene carbonate Benzyl alcohol Ethanol

Phyto chemical and bio activities research on Tinospora crispa (Patawali)

International Nuclear Information System (INIS)

Shakirah Abdul Shukor

2010-01-01

The usage of traditional therapeutic medicine is gaining attention as consumption to modern therapeutic medicine can affect health and also causing death. Because of this resurgence of interest, the research on medicinal plant is growing phenomenally in Malaysia as Tinospora crispa is one of the potential candidates and this plant is been use since long time ago as medicine. Solvent extraction method run on Tinospora crispa's stem had resulted 5 extracts which were hexane, chloroform, butanol, aqueous and methanol. Phyto chemical screening of hexane extract showed existence of alkaloid, flavonon, polyphenol substances and steroid type saponins. Chloroform extract consists alkaloid and triterpenoid type saponins while alkaloid, flavon and polyphenol substances found in butanol extract. Aqueous extract consist free acid and steroid type saponins whereas alkaloid, tannin and triterpenoid type saponins were found in methanol extract. Hexane, chloroform, and butanol extracts shows inhibition zone for bacteria gram-positive, Staphylococcus aureus where each extracts give inhibitory zone diameter of 1.5 cm, 1.3 cm, and 1.2 cm. There is no inhibitory zone for methanol and aqueous extract. As observation for bacteria gram-negative, Escherichia coli shows negative result for inhibitory zone. The LC50 acute for hexane, chloroform, butanol, aqueous and methanol extracts are 3162.28 ppm, 7813.71 ppm, 380.72 ppm, 662.87 ppm, dan 1847.85 ppm respectively. LC50 chronic for hexane, chloroform, butanol, aqueous and methanol extracts are 273.84 ppm, 259.29 ppm, 17.78 ppm, 12.02 ppm, dan 15.44 ppm respectively. Butanol, aqueous and methanol extracts gives higher relative toxicity compared to potassium dichromate. Overall, Tinospora crispas extracts are toxic compared with relative toxicity of potassium dichromate. The solvent system of toulene, acetone and chloroform with the proportion of 8: 2: 5 for hexane extract indicated 9 substances where chloroform extract yielded 6 substance

Nanometre-sized pores in coal: Variations between coal basins and coal origin

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Sakurovs, Richard; Koval, Lukas; Grigore, Mihaela; Sokolava, Anna; Ruppert, Leslie F.; Melnichenko, Yuri B.

2018-01-01

We have used small angle neutron scattering (SANS) to investigate the differences in methane and hexane penetration in pores in bituminous coal samples from the U.S., Canada, South Africa, and China, and maceral concentrates from Australian coals. This work is an extension of previous work that showed consistent differences between the extent of penetration by methane into 10–20 nm size pores in inertinite in bituminous coals from Australia, North America and Poland.In this study we have confirmed that there are differences in the response of inertinite to methane and hexane penetration in coals sourced from different coal basins. Inertinite in Permian Australian coals generally has relatively high numbers of pores in the 2.5–250 nm size range and the pores are highly penetrable by methane and hexane; coals sourced from Western Canada had similar penetrability to these Australian coals. However, the penetrability of methane and hexane into inertinite from the Australian Illawarra Coal Measures (also Permian) is substantially less than that of the other Australian coals; there are about 80% fewer 12 nm pores in Illawarra inertinite compared to the other Australian coals examined. The inertinite in coals sourced from South Africa and China had accessibility intermediate between the Illawarra coals and the other Australian coals.The extent of hexane penetration was 10–20% less than CD4 penetration into the same coal and this difference was most pronounced in the 5–50 nm pore size range. Hexane and methane penetrability into the coals showed similar trends with inertinite content.The observed variations in inertinite porosity between coals from different coal regions and coal basins may explain why previous studies differ in their observations of the relationships between gas sorption behavior, permeability, porosity, and maceral composition. These variations are not simply a demarcation between Northern and Southern Hemisphere coals.

Lipase inhibitory activity of Carica papaya, Chrysophyllum cainito, Corcorus olitorius, Cympogon citrates and Syzygium cumini extracts

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Briones, A.T.

2017-09-01

Full Text Available The lipase inhibitory action of Carica papaya, Chrysophyllum cainito, Corcorus olitorius, Cymbopogon citrates and Syzygium cumini were evaluated to explore for the presence of anti-obesity compounds and their potential weight-lowering activity. Enzyme inhibition results of the alcoholic extracts of the five plants showed that C. cainito has the highest percent inhibition at 74.91% while S. cumini, C. citratus, C. olitorius and C. papaya obtained less than 50% average inhibition. C. cainito was partitioned using hexane and ethyl acetate to further concentrate the bioactive compounds. The lipase inhibition assay of hexane and ethyl acetate extracts showed 92.11% inhibition and 21.9% inhibition, respectively. The greater activity in the former may imply that majority of potential anti-lipase constituents are found in the hexane portion.

Composição química da glândula abdominal da fêmea da mariposa Castnia licus (Drury (Lepidoptera:Castniidae: possíveis feromônios e precursores Chemical composition from female pheromone gland of Castnia licus (Drury (Lepidoptera: Castniidae

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Lúcia M. C. Rebouças

1999-09-01

Full Text Available The hexane and methanolic extracts from pheromonal glands of Castnia licus (Drury virgin females have been studied. Analyses by gas chromatography and mass spectrometry allowed us to determine the major constituents present in the hexane extract as n-alkanes C21 to C30, (Z-9-hexadecenoic acid (C16, and (Z-9-octadecenoic acid (C18 and hexadecanoic acid (C16. Aldehyds, alkenes and acetates were also detected in low concentrations in the extracts. Female pheromone glands were analysed for pheromone precursors using the methanolic extract. In addition to the compounds methyl hexadecanoate and methyl (Z-9-octadecenoate, the glandular tissue contains a homologous series of methyl esters from C12 to C24. The hexane extract of the female abdomenal glands elicited activity from males in a behavioural bioassay.

Evaluation of the Antioxidant and Anti-glication Effects of the Hexane Extract from Piper auritum Leaves in Vitro and Beneficial Activity on Oxidative Stress and Advanced Glycation End-Product-Mediated Renal Injury in Streptozotocin-Treated Diabetic Rats

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Adriana Maria Neira Gonzalez

2012-10-01

Full Text Available The aim of this study was to investigate the antioxidant activity of hexane extracts from leaves of Piper auritum (HS. Eight complementary in vitro test methods were used, including inhibition of DPPH· radicals, nitric oxide, superoxide anion, ion-chelating, ABTS, oxygen radical absorbance capacity, β-carotene bleaching and peroxy radical scavenging. The results indicated that HS possesses high antioxidant activity. To add to these finding we tested the effect against oxidative stress in liver, pancreas and kidney in diabetic rats. Low levels of SOD, CAT, GPx and GSH in diabetic rats were reverted to near normal values after treatment with HS. These results suggest that P. auritum prevents oxidative stress, acting as a suppressor of liver cell damage. Given the link between glycation and oxidation, we proposed that HS might possess significant in vitro antiglycation activity. Our data confirmed the inhibitory effect of HS on bovine serum albumin, serum glycosylated protein, glycation of LDL, and glycation hemoglobin. The effect of HS on diabetic renal damage was investigated using streptozotocin-induced diabetic rats. The oral administration of HS at a dose of 200 and 400 mg/kg body weight/day for 28 days significantly reduced advanced glycation endproduct (AGE formation, elevated renal glucose and thiobarbituric acid-reactive substance levels in the kidneys of diabetic rats. This implies that HS would alleviate the oxidative stress under diabetes through the inhibition of lipid peroxidation. These findings indicate that oxidative stress is increased in the diabetic rat kidney and that HS can prevent renal damage associated with diabetes by attenuating the oxidative stress.

Antioxidant activity of Vitex agnus-castus L. extracts.

Science.gov (United States)

Sağlam, Hüsniye; Pabuçcuoğlu, Aysun; Kivçak, Bijen

2007-11-01

The ethanol, n-hexane and water extracts of Vitex agnus-castus L. leaves and fruits were screened for antioxidant activity. The antioxidant activity of plant extracts was determined by an improved assay based on the decolorization of the radical monocation of 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS.+). The water and ethanol extracts showed stronger antioxidant activity than the n-hexane extracts. Copyright (c) 2007 John Wiley & Sons, Ltd.

Poly(ethylene oxide) surfactant polymers

OpenAIRE

VACHEETHASANEE, KATANCHALEE; WANG, SHUWU; QIU, YONGXING; MARCHANT, ROGER E.

2004-01-01

We report on a series of structurally well-defined surfactant polymers that undergo surface-induced self-assembly on hydrophobic biomaterial surfaces. The surfactant polymers consist of a poly(vinyl amine) backbone with poly(ethylene oxide) and hexanal pendant groups. The poly(vinyl amine) (PVAm) was synthesized by hydrolysis of poly(N-vinyl formamide) following free radical polymerization of N-vinyl formamide. Hexanal and aldehyde-terminated poly (ethyleneoxide) (PEO) were simultaneously att...

Anti-inflammatory, anti-cholinergic and cytotoxic effects of Sida rhombifolia.

Science.gov (United States)

Mah, Siau Hui; Teh, Soek Sin; Ee, Gwendoline Cheng Lian

2017-12-01

Sida (Malvaceae) has been used as a traditional remedy for the treatment of diarrhoea, malarial, gastrointestinal dysentery, fevers, asthma and inflammation. This study evaluates the anti-inflammatory, cytotoxic and anti-cholinergic activities of Sida rhombifolia Linn. whole plant for the first time. S. rhombifolia whole plant was extracted by n-hexane, ethyl acetate and methanol using Soxhlet apparatus. The plant extracts were evaluated for their antioxidant (DPPH, FIC and FRAP), anti-inflammatory (NO and protein denaturation inhibitions), cytotoxic (MTT) and anti-cholinesterase (AChE) properties in a range of concentrations to obtain IC 50 values. GC-MS analysis was carried out on the n-hexane extract. The ethyl acetate extract exhibited the most significant antioxidant activities by scavenging DPPH radicals and ferrous ions with EC 50 of 380.5 and 263.4 μg/mL, respectively. In contrast, the n-hexane extract showed the strongest anti-inflammatory activity with IC 50 of 52.16 and 146.03 μg/mL for NO and protein denaturation inhibition assays, respectively. The same extract also revealed the strongest effects in anti-cholinesterase and cytotoxic tests at the concentration of 100 μg/mL, AChE enzyme inhibition was 58.55% and human cancer cells, SNU-1 and Hep G2 inhibition was 68.52% and 47.82%, respectively. The phytochemicals present in the n-hexane extract are palmitic acid, linoleic acid and γ-sitosterol. The present study revealed that the n-hexane extract possessed relatively high pharmacological activities in anti-inflammation, cytotoxicity and anti-cholinesterase assays. Thus, further work on the detail mechanism of the bioactive phytochemicals which contribute to the biological properties are strongly recommended.

Growth inhibition of human breast cancer cells and down-regulation of ODC1 and ADA genes by Nepeta binaloudensis

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Akbar Safipour Afshar

Full Text Available ABSTRACT Nepeta binaloudensis Jamzad, Lamiaceae, is a rare medicinal plant endemic to Iran. In spite of many studies about the chemical constituents and antibacterial effects of this species, no report has been provided about its cytotoxic and anticancer activities. In this study we have evaluated the effects of EtOH 70%, hexane and aqueous extracts of N. binaloudensis on the cell proliferation and n-hexane extract on the expression of adenosine deaminase and ornithine decarboxylase 1 genes in breast cancer cell lines (MCF-7, MDA-MB-231 compared to non-cancer line (MCF-10A. The cell lines were subjected to increasing doses of the extracts ranging from 10 to 320 µg/ml. Cell viability was quantified by MTS assay. Expression of adenosine deaminase and ornithine decarboxylase 1 genes was analyzed by real time PCR. N. binaloudensis inhibited the growth of malignant cells in a time and dose-dependent manner. Among extracts of N. binaloudensis, the hexane extract was found to be more toxic compared to other extracts. Results showed a marked decrease in the expression of ornithine decarboxylase 1 and adenosine deaminase genes in cancer cell lines. At 60 µg/ml concentration of N. binaloudensis hexane extract ornithine decarboxylase 1 and adenosine deaminase mRNA expression were reduced 4.9 fold and 3.5 fold in MCF-7 cell line and 3.6 fold and 2.6 fold in MDA-MB-231 cell line compared to control, respectively. The result of our study highlights the potential influences of N. binaloudensis hexane extract on ornithine decarboxylase 1 and adenosine deaminase genes expression in breast cancer cells and its relation to inhibition of cancer cell growth.

Antinociceptive effect in mice of a hydroalcoholic extract of Neurolaena lobata (L.) R. Br. and its organic fractions.

Science.gov (United States)

Gracioso, J S; Paulo, M Q; Hiruma Lima, C A; Souza Brito, A R

1998-12-01

An infusion of the aerial parts of Neurolaena lobata (L.) R. Br. (Compositae-Asteraceae) is used in Caribbean folk medicine to treat several kinds of pain. In this investigation we studied the acute oral toxicity of the hydroalcoholic extract of the plant and the antinociceptive effect of the extract and of its hexane- and chloroform-partitioned fractions, given orally, in nociception and inflammatory models in mice. No signs of toxicity were observed for oral doses up to 5000 mg kg(-1) in mice. Morphine hydrochloride (100 mg kg(-1)), dipyrone sodium (200 mg kg(-1)), the hydroalcoholic extract (1000 mg kg(-1)), and its chloroform- and hexane-partitioned fractions (100 mg kg(-1)) significantly inhibited acetic acid-induced abdominal constriction in mice (100, 95, 47, 62 and 60% inhibition, respectively when compared with the negative control). In the hot-plate test in mice, morphine hydrochloride, the chloroform- and hexane-partitioned fractions, but not the hydroalcoholic extract, resulted in a significant latency increase in all observation times. In the acetic acid-induced abdominal constriction in mice, pretreatment of the animals with naloxone significantly reversed the analgesic effect of morphine, but not that of the hydroalcoholic extract or of its hexane- and chloroform-partitioned fractions. Finally, administration of the hexane- and chloroform-partitioned fractions (100 mg kg(-1)) had a significant anti-oedematogenic effect on carrageenan-induced oedema in mice. These data show that the hydroalcoholic extract of N. lobata and, in particular, its partitioned fractions have significant analgesic properties when assessed through these pain models. Their antinociceptive effect might be the result of interference with the inflammatory process.

Larvicidal activity of Annona senegalensis and Boswellia dalzielii leaf fractions against Aedes aegypti (Diptera: Culicidae

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Younoussa Lame

2014-12-01

Full Text Available The purpose of the present study was to evaluate the larvicidal activity of leaf fractions of Annona senegalensis and Boswellia dalzielii against fourth instar larvae of Aedes aegypti. Fourth instar larvae of Ae. aegypti were exposed for 24 hours to various concentrations (312.5-2500 mg/L of methanolic crude extract and its fractions obtained with n-hexane, chloroform, ethyl-acetate and methanol solvents, following WHO method. The mortalities recorded were subjected to ANOVA test for mean comparison and Probit analysis to determine LC50. Preliminary phytochemical screening test for some components of the plants assessed were also evaluated. The phytochemical screening of the two plants revealed the presence of alkaloids, steroids, phenolic compounds, terpenoids, fats and oils in the crude extracts which, after splitting were most distributed in n-hexane and chloroform fractions. Apart from methanol fraction, all products used showed a significant (P<0.001 concentration-dependent toxicity against Ae. aegypti larvae. The LC50 recorded with crude extract were 759.6 and 830.4 mg/L for A. senegalensis and B. dalzielli respectively. After fractionation, n-hexane and chloroform fractions of A. senegalensis revealed more effective activity than others with CL50 values of 379.3 and 595.2 mg/L respectively. As for B. dalzielli, n-hexane (LC50=537.1 mg/L and chloroform (LC50=585.5 mg/L fractions were also the most effective. These results suggest that the n-hexane and chloroform fractions of these plants as a promising larvicide against Ae. aegypti and can constitute the best basic and vital step in the development of a botanical insecticide source.

OPTIMIZATION OF SESAME SEEDS OIL EXTRACTION OPERATING CONDITIONS USING THE RESPONSE SURFACE DESIGN METHODOLOGY

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HAITHAM OSMAN

2016-12-01

Full Text Available This paper applies Response Surface Design (RSD to model the experimental data obtained from the extraction of sesame seeds oil using n-hexane, chloroform and acetone as solvents under different operating conditions. The results obtained revealed that n-hexane outperformed the extraction obtained using chloroform and acetone. The developed model predicted that n-hexane with a rotational speed of 547 rpm and a contact time between the solvent and seeds of 19.46 hours with solvent: seeds ratio of 4.93, yields the optimum oil extracted of 37.03 %, outperforming chloroform and acetone models that gave prediction for 4.75 and 4.21 respectively. While the maximum predictions yield for chloroform is 6.73 %, under the operating conditions of 602 rpm, and 24 hours contact time, with a ratio of solvent: seeds of 1.74. On the other hand the acetone maximum prediction is only 4.37 %, with operational conditions of 467 rpm, and 6.00 hours contact time, with a ratio of solvent: seeds of 1. It is has been found that the maximum oil extraction yield obtained from the chloroform (6.73 % and Acetone (4.37 % is much lower than that predicted by n-hexane 37.03 %.

Insecticidal activity of Jatropha curcas extracts against housefly, Musca domestica.

Science.gov (United States)

Chauhan, Nitin; Kumar, Peeyush; Mishra, Sapna; Verma, Sharad; Malik, Anushree; Sharma, Satyawati

2015-10-01

The hexane and ether extracts of leaves, bark and roots of Jatropha curcas were screened for their toxicity against different developmental stages of housefly. The larvicidal, pupicidal and adulticidal activities were analysed at various concentrations (0.78-7.86 mg/cm(2)) of hexane and ether extracts. The lethal concentration values (LC50) of hexane extract of J. curcas leaves were 3.0 and 0.27 mg/cm(2) for adult and larval stages of housefly, respectively, after 48 h. Similarly, the ether extract of leaf showed the LC50 of 2.20 and 4.53 mg/cm(2) for adult and larval stages of housefly. Least toxicity was observed with hexane root extract of J. curcas with LC50 values of 14.18 and 14.26 mg/cm(2) for adult and larvae of housefly, respectively, after 48 h. The variation in LC50 against housefly pupae was found to be 8.88-13.10 mg/cm(2) at various J. curcas extract concentrations. The GC-MS analysis of J. curcas leaf extract revealed the presence of trans-phytol (60.81 %), squalene (28.58 %), phytol (2.52 %) and nonadecanone (1.06 %) as major components that could be attributed for insecticidal activity of J. curcas extracts.

Biological Activity of Piper aduncum extracts on Anticarsia gemmatalis (Hübner (Lepidoptera: Erebidae and Spodoptera frugiperda (J.E. Smith (Lepidoptera: Noctuidae

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DAIANE C. LUCENA

2017-08-01

Full Text Available ABSTRACT Piper aduncum found naturally in the Amazon and southeastern Brazil, is known for its secondary metabolites that have activity on insects. Anticarsia gemmatalis and Spodoptera frugiperda are among the major insect pests associated with agricultural production. This research evaluated the biological activity of hexane, ethyl acetate, and ethanol extracts of P. aduncum leaves on mortality and duration of larval and pupal periods, as well as weight, width, and length of A. gemmatalis and S. frugiperda pupae. The mortality of A. gemmatalis larvae in trials with P. aduncum extracts were 93.3% (hexane and 90% (ethyl acetate, estimating LC50 of 6.35 and 5.79 mg/mL, respectively. Mortality in S. frugiperda submitted to the hexane extract ranged from 3.33% to 96.66% (LC50 of 8.22 mg/mL. The ethanol extract induced low mortality (3.33% to 23.33%. The P. aduncum extracts did not affect the development of S. frugiperda pupae. In A. gemmatalis differences in weight and length occurred. The chemical characterization was by GC-MS, which revealed that the major constituent in the hexane extract of P. aduncum was apiol (90.7%. P. aduncum extracts are important and promising components to manage A. gemmatalis and S. frugiperda, which cause extensive production losses.

Biological Activity of Piper aduncum extracts on Anticarsia gemmatalis (Hübner) (Lepidoptera: Erebidae) and Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae).

Science.gov (United States)

Lucena, Daiane C; Bertholdo-Vargas, Lucia R; Silva, Wilson C; Machado, Aaron F; Lopes, Tamiris S; Moura, Sidnei; Barros, Neiva M

2017-01-01

Piper aduncum found naturally in the Amazon and southeastern Brazil, is known for its secondary metabolites that have activity on insects. Anticarsia gemmatalis and Spodoptera frugiperda are among the major insect pests associated with agricultural production. This research evaluated the biological activity of hexane, ethyl acetate, and ethanol extracts of P. aduncum leaves on mortality and duration of larval and pupal periods, as well as weight, width, and length of A. gemmatalis and S. frugiperda pupae. The mortality of A. gemmatalis larvae in trials with P. aduncum extracts were 93.3% (hexane) and 90% (ethyl acetate), estimating LC50 of 6.35 and 5.79 mg/mL, respectively. Mortality in S. frugiperda submitted to the hexane extract ranged from 3.33% to 96.66% (LC50 of 8.22 mg/mL). The ethanol extract induced low mortality (3.33% to 23.33%). The P. aduncum extracts did not affect the development of S. frugiperda pupae. In A. gemmatalis differences in weight and length occurred. The chemical characterization was by GC-MS, which revealed that the major constituent in the hexane extract of P. aduncum was apiol (90.7%). P. aduncum extracts are important and promising components to manage A. gemmatalis and S. frugiperda, which cause extensive production losses.

Improvement of Biogas Production from Orange Peel Waste by Leaching of Limonene

Science.gov (United States)

Wikandari, Rachma; Nguyen, Huong; Millati, Ria; Niklasson, Claes; Taherzadeh, Mohammad J.

2015-01-01

Limonene is present in orange peel wastes and is known as an antimicrobial agent, which impedes biogas production when digesting the peels. In this work, pretreatment of the peels to remove limonene under mild condition was proposed by leaching of limonene using hexane as solvent. The pretreatments were carried out with homogenized or chopped orange peel at 20–40°C with orange peel waste and hexane ratio (w/v) ranging from 1 : 2 to 1 : 12 for 10 to 300 min. The pretreated peels were then digested in batch reactors for 33 days. The highest biogas production was achieved by treating chopped orange peel waste and hexane ratio of 12 : 1 at 20°C for 10 min corresponding to more than threefold increase of biogas production from 0.061 to 0.217 m3 methane/kg VS. The solvent recovery was 90% using vacuum filtration and needs further separation using evaporation. The hexane residue in the peel had a negative impact on biogas production as shown by 28.6% reduction of methane and lower methane production of pretreated orange peel waste in semicontinuous digestion system compared to that of untreated peel. PMID:25866787

Improvement of Biogas Production from Orange Peel Waste by Leaching of Limonene

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Rachma Wikandari

2015-01-01

Full Text Available Limonene is present in orange peel wastes and is known as an antimicrobial agent, which impedes biogas production when digesting the peels. In this work, pretreatment of the peels to remove limonene under mild condition was proposed by leaching of limonene using hexane as solvent. The pretreatments were carried out with homogenized or chopped orange peel at 20–40°C with orange peel waste and hexane ratio (w/v ranging from 1 : 2 to 1 : 12 for 10 to 300 min. The pretreated peels were then digested in batch reactors for 33 days. The highest biogas production was achieved by treating chopped orange peel waste and hexane ratio of 12 : 1 at 20°C for 10 min corresponding to more than threefold increase of biogas production from 0.061 to 0.217 m3 methane/kg VS. The solvent recovery was 90% using vacuum filtration and needs further separation using evaporation. The hexane residue in the peel had a negative impact on biogas production as shown by 28.6% reduction of methane and lower methane production of pretreated orange peel waste in semicontinuous digestion system compared to that of untreated peel.

Antibakteri Fraksi n-Heksana Kulit Hylocereus polyrhizus Terhadap Staphylococcus epidermidis dan Propionibacterium acnes

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Sri Wardaningsih

2014-12-01

Full Text Available Acne can be caused by Propionibacterium acnes and Staphylococcus epidermidis. Using antibiotic for the acne theraphy in a long term period can cause resistance, organ detriment and imunohypersensitivity. Red dragon fruit’s peel (Hylocereus polyrhizus is one of natural materials which can be used for alternative antibacterial. The aim of this study was to determine the antibacterial activity of n-Hexane fraction of red dragon fruit’s peel against S. epidermidis dan P. acnes with the method of disc diffusion Kirby-Bauer. Red dragon fruit’s peel powder was macerated with chloroform and then fractionated with n-Hexane. The result of phytochemical screening showed that red dragon fruit’s peel contained terpenoid and alkaloid. Clindamycin 4µg/disk was used for positive control while DMSO 10% was used for negative control. Data was analyzed using R-Commander program 3.0.3 version. This research showed that n-Hexane fraction of red dragon fruit’s peel had antibacterial activity against P. acnes where the average zone of inhibition obtained from the concentrations of 20; 40; and 80 mg/mL were 9 mm; 10,25 mm; and 10,5 mm, respectively. However, n-Hexane fraction of red dragon fruit’s peel didn’t have antibacterial activity against S. epidermidis.

Chemical composition and antibacterial activity of Opuntia ficus-indica f. inermis (cactus pear) flowers.

Science.gov (United States)

Ennouri, Monia; Ammar, Imene; Khemakhem, Bassem; Attia, Hamadi

2014-08-01

Opuntia ficus-indica f. inermis (cactus pear) flowers have wide application in folk medicine. However, there are few reports focusing on their biological activity and were no reports on their chemical composition. The nutrient composition and hexane extracts of Opuntia flowers at 4 flowering stages and their antibacterial and antifungal activities were investigated. The chemical composition showed considerable amounts of fiber, protein, and minerals. Potassium (K) was the predominant mineral followed by calcium (Ca), magnesium (Mg), sodium (Na), iron (Fe), and zinc (Zn). The main compounds in the various hexane extracts were 9.12-octadecadienoic acid (29-44%) and hexadecanoic acid (8.6-32%). The antibacterial activity tests showed that O. inermis hexane extracts have high effectiveness against Escherichia coli and Staphylococcus aureus, making this botanical source a potential contender as a food preservative or food control additive.

Evaluation of Antimicrobial Activity of Root Extracts of Abitulon indicum

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Krishna Rao MORTHA

2015-06-01

Full Text Available Antimicrobial activity of Abitulon indicum roots was studied against seven pathogenic bacteria and three fungal strains by agar well diffusion method. Antimicrobial activity was recorded for hexane, chloroform, methanol, ethanol and aqueous extracts. Alcohol (ethanol and methanol extracts exhibited the highest degree of antimicrobial activity compared to aqueous, chloroform and hexane extracts. Pseudomonas aeruginosa was turned out to be the most susceptible bacterium to the crude root chemical constituents, using the standard Tetracycline and Clotrimazole. Minimum inhibition concentration values of hexane, chloroform, methanol, ethanol and aqueous extracts were determined by the agar dilution method and ranged between 62.5 and 1,000 µg. The study suggested that the root extracts possess bioactive compounds with antimicrobial activity against the tested bacteria and fungi, revealing a significant scope to develop a novel broad spectrum of antimicrobial drug formulation from Abitulon indicum.

Evaluation of the insecticidal activity of the extracts from Piper grande Vahl (Piperaceae) using the biological model Drosophila melanogaster

International Nuclear Information System (INIS)

Granados N, Hillmer; Saez V, Jairo; Robles, Carolina; Vasquez, Luis F; Moreno, Maria E; Acevedo, Jose M; Pelaez, Carlos A; Callejas, Ricardo

2002-01-01

In this study, using the life cycle interruption test with the Drosophila melanogaster model, under (in-vitro conditions), the n-Hexane (roots and stems) and the EtOAc (roots and leaves) extracts were evaluated as insecticides and the results were promising. The larvae instars showed a significant activity reflected in the reduction of pupae population with respect to the control. The step from Pupae to adult did no show inhibition because in all cases the average of the relation pupae adult is found in values very near 1. The n-Hexane and the EtOAc extracts from roots were the most active with LC50 of 698.2 ppm and 1210.7 ppm. The n-Hexane (stems) and EtOAc (leaves) extracts showed a moderate activity with LC50 of 1654.1 ppm and 2376.0 ppm

Antibacterial activity of extracts of six macroalgae from the northeastern brazilian coast

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Lima-Filho José Vitor M.

2002-01-01

Full Text Available Hexane, chloroform and ethanol extracts of six marine macroalgae (Rhodophyta and Chlorophyta from North Ceará coast (Northeast Brazil were evaluated for antibacterial activity by the single disk method. Best results were shown by the hexane extracts of Amansia multifida against enteric Gram-negative strains such as Enterobacter aerogenes, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, S. cholerae-suis, Serratia marcescens, Vibrio cholerae and the Gram-positive bacteria Bacillus subtilis and Staphylococcus aureus.

New Technology for Oil/Water Emulsion Treatment: Phases I and II

Science.gov (United States)

1998-05-15

demand (COD) IV-16 by EPA Method 410.4, and the quantity of filterable solids (QFS) by gravimetry . A field laboratory for the analysis of O&G and QFS...This method measures n-hexane extractable material (HEM) and silica-gel- treated hexane extractable material (SGT-HEM) by extraction and gravimetry ...collection vial • Routine formations of a precipitate when the method-recommended spiking standard, a mixture of hexadecane and stearic acid in

Medium Caliber Lead-Free Electric Primer. Version 2

Science.gov (United States)

2012-09-01

2008). Safe Drinking Water Act of 1986 lists lead compounds as carcinogens (27 CCR 27001 – Dec. 2008). EPA began a Phase I assessment to determine...primer cups was our standard method, wet loading using solvents (hexane and iso -propanol) was investigated to reduce risk of accidental ignition...LOADING OPERATION (Single Die) Wet primer mix charge with solvent (Hexane/ Iso -Propanol) and stir to mix to a uniform slurry Insert primer cup in

Study of thermodynamic and transport properties of binary liquid mixtures of n-decane with hexan-2-ol, heptan-2-ol and octan-2-ol at T = 298.15 K. Experimental results and application of the Prigogine–Flory–Patterson theory

International Nuclear Information System (INIS)

Mahajan, Aravind R.; Mirgane, Sunil R.

2013-01-01

Highlights: • The large positive V m E values are obtained for the binary mixtures at 298.15 K. • Excess isentropic compressibilities for the binary mixtures are positive over the whole composition range. • The values of G ∗E for all binary mixtures are negative over entire mole fraction. • Viscosities measured for the binary mixtures were correlated with values calculated by various viscosity models. • PEP theory, Bloomfield and Dewan model and Jouyban–Acree model are also used to correlate the experimental data. -- Abstract: Densities and viscosities of binary mixtures of n-decane with hexan-2-ol, heptan-2-ol and octan-2-ol have been measured over the entire range of composition at T = 298.15 K and at atmospheric pressure. From the experimental values of density and viscosity, the excess molar volumes (V m E ) and excess Gibbs energy of activation of viscous flow (G ∗E ) have been calculated. These results were fitted to Redlich–Kister polynomial equations to estimate the binary coefficients and standard errors. Jouyban–Acree model is used to correlate the experimental values of density, viscosity and ultrasonic velocity at T = 298.15 K. The results of the viscosity-composition are discussed in the light of various viscosity semi-empirical equations. The experimental results have been used to test the applicability of the Prigogine–Flory–Patterson (PFP) theory. The values of Δln η have also been analysed using Bloomfield and Dewan model. The experimental and calculated quantities are used to study the nature of mixing behaviour between the mixtures

Efficacy of Odor Scavengers in Reducing Odor Compounds in Water, Milk, and Soymilk

OpenAIRE

Norton, Jenny Lynn

2003-01-01

Odor detection thresholds of hexanal, 2-heptenal, 2-pentanone, and 2,4-nonadienal were determined in spring water, high temperature short time (HTST) 2% fat milk, and extended shelf life soymilk. The efficacy of odor scavenger's beta-cyclodextrin, D-sorbitol, and nylon 6 in removing these odors was also determined. The odor thresholds of the different odor and media combinations were as follows: hexanal in spring water, milk, and soymilk were 585, 339, and 536 ppb respectively; 2-heptenal ...

Report: Antimicrobial activity of Kalanchoe laciniata.

Science.gov (United States)

Manan, Maria; Hussain, Liaqat; Ijaz, Hira; Qadir, Muhammad Imran

2016-07-01

This study was conducted to identify antimicrobial potential of Kalanchoe laciniata. The plants were extracted with 30-70% aqueous-methanol and n-hexane. The antimicrobial activities were examined using agar well diffusion method against bacteria (Staphylococcus aureus, Escherichia coli) and fungi (Candidaalbicans). Results showed that E. coli were more sensitive than Staphylococcus aureus and Candida albicans. The largest zone of inhibition (52 mm) was recorded against E. coli with the n-hexane extract of Kalanchoe laciniata.

Mobility Studies of (14)C-Chlorpyrifos in Malaysian Oil Palm Soils.

Science.gov (United States)

Halimah, Muhamad; Ismail, B Sahid; Nashriyah, Mat; Maznah, Zainol

2016-01-01

The mobility of (14)C-chlorpyrifos using soil TLC was investigated in this study. It was found that chlorpyrifos was not mobile in clay, clay loam and peat soil. The mobility of (14)C-chlorpyrifos and non-labelled chlorpyrifos was also tested with silica gel TLC using three types of developing solvent hexane (100%), hexane:ethyl acetate (95:5, v/v); and hexane:ethyl acetate (98:2, v/v). The study showed that both the (14)C-labelled and non-labelled chlorpyrifos have the same Retardation Factor (Rf) for different developing solvent systems. From the soil column study on mobility of chlorpyrifos, it was observed that no chlorpyrifos residue was found below 5 cm depth in three types of soil at simulation rainfall of 20, 50 and 100 mm. Therefore, the soil column and TLC studies have shown similar findings in the mobility of chlorpyrifos.

Optimizing the Production of Biodiesel Using Lipase Entrapped in Biomimetic Silica

Energy Technology Data Exchange (ETDEWEB)

I-Ching Kuan; Chia-Chi Lee; Bing-Hong Tsai; Shiow-Ling Lee; Wei-Ting Lee; Chi-Yang Yu [Department of Bioengineering, Tatung Univ., Taipei, Taiwan (China)

2013-04-15

We entrapped lipase from Pseudomonas cepacia in polyallylamine-mediated biomimetic silica, and then applied entrapped lipase to the synthesis of biodiesel with soybean oil or waste cooking oil as a feedstock. The effects of reaction temperature, substrate molar ratio (methanol/oil) and n-hexane content (w/w of oil) were evaluated using response surface methodology (RSM) combined with Box-Behnken design. The optimal reaction conditions for soybean oil were 43.6 deg C, substrate molar ratio of 4.3%, and 75% n-hexane. The predicted and experimental values of biodiesel conversion were 79% and 76%, respectively. The optimal reaction conditions for waste cooking oil were 43.3 deg C, substrate molar ratio of 5%, and 38% n-hexane. The predicted and experimental values of conversion were 68% and 67%, respectively. The conversion efficiency remained the same even after 1-month storage of entrapped lipase at 4 deg C or room temperature.

Allelopathic potential of Artemisia arborescens: isolation, identification and quantification of phytotoxic compounds through fractionation-guided bioassays.

Science.gov (United States)

Araniti, Fabrizio; Lupini, Antonio; Sorgonà, Agostino; Conforti, Filomena; Marrelli, Mariangela; Statti, Giancarlo Antonio; Menichini, Francesco; Abenavoli, Maria Rosa

2013-01-01

The aerial part of Artemisia arborescens L. (Asteraceae) was extracted with water and methanol, and both extracts were fractionated using n-hexane, chloroform, ethyl acetate and n-butanol. The potential phytotoxicity of both crude extracts and their fractions were assayed in vitro on seed germination and root growth of lettuce (Lactuca sativa L.), a sensitive species largely employed in the allelopathy studies. The inhibitory activities were analysed by dose-response curves and the ED 50 were estimated. Crude extracts strongly inhibited both germination and root growth processes. The fraction-bioassay indicated the following hierarchy of phytotoxicity for both physiological processes: ethyl acetate ≥ n-hexane > chloroform ≥ n-butanol. On the n-hexane fraction, GC-MS analyses were carried out to characterise and quantify some of the potential allelochemicals. Twenty-one compounds were identified and three of them, camphor, trans-caryophyllene and pulegone were quantified.

Phyto chemical and antioxidant screening of extracts of Aquilaria malaccensis leaves

International Nuclear Information System (INIS)

Salmah Moosa

2010-01-01

Aquilaria malaccensis is an endangered economic plant used for production of agar wood worldwide. The sequential maceration extraction methods utilizing solvents with different polarities namely hexane, ethyl acetate and methanol yielded the corresponding crude extract. The aqueous and methanol extracts along with dry powder of leaf of the plant was screened for the presence of phytochemicals. They were also tested for antioxidant activities. The result indicates the presence of alkaloids, flavanoids, triterpenoids, steroids and tannins. The phyto chemical screening suggests that flavanoids present in this species might provide a great value of antioxidant activity. Preliminary screenings of the free radical scavenging activity on the extracts of the plants with 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) were tested and showed positive result. Quarcetine was used as reference standard. The extracts exhibited strong antioxidant activity radical scavenging activity with IC50 value of 8.0 x 102 μg/ ml, 1.6 x 102 μg/ ml, 1.4 x 102 μg/ ml, 30.0 μg/ ml and 3.33 μg/ ml for hexane, DCM, ethyl acetate, methanol and quercetine respectively. Determination on antioxidant activity of each crude extract showed that methanol crude extract had the highest IC50 value than ethyl acetate, dichloromethane and hexane crude extract. This means that methanol possess the highest inhibition of DPPH radical scavenging activity compared to the other crudes but still lower than Quercetin (standard). Phyto chemical analysis on the hexane extract of Aquilaria malaccensis has been conducted. Several chromatographic methods have been employed to the hexane of the leaves which led to the isolation of three compounds namely Stigmasterol, β-sitosterol and 3-fridelanol. The present study has proved the usefulness of agar wood tree for medicinal purposes and its potential as a source of useful drugs. (author)

Aromatization of alkanes over Pt promoted conventional and mesoporous gallosilicates of MEL zeolite

KAUST Repository

Akhtar, M. N.; Al-Yassir, N.; Al-Khattaf, S.; Čejka, Jiří

2012-01-01

Aromatization of hexane and propane was investigated over Pt promoted mesoporous gallium-containing HZSM-11 with controlled mesoporosity generated by desilication. Prepared catalysts were characterized by nitrogen adsorption, X-ray powder diffraction, scanning electron microscopy, Fourier transform infrared of chemisorbed pyridine, and NH 3 temperature programmed desorption confirming the development of intracrystalline mesoporosity of Ga-containing HZSM-11. The catalytic activities, which were compared in the aromatization of n-hexane and propane, increased upon desilication. The aromatization of n-hexane decreased in the following order, Pt/mesoporous GaZSM-11 Pt/conventional GaZSM-11 mesoporous GaZSM-11 > conventional GaZSM-11. Hexane conversion reached 70.1% over mesoporous Pt/GaZSM-11 with Si/Ga of 61, as compared with 29.6 and 24.9% for corresponding mesoporous and conventional GaZSM-11 (Si/Ga = 94), respectively, for experiments at liquid hour space velocity of 3.6 h -1, and 540 °C. Comparison of BTX (benzene-toluene-xylene) selectivity at the conversion level of ∼21.0% revealed that Pt/mesoporous GaZSM-11 is more selective than corresponding mesoporous and conventional GaZSM-11. The BTX selectivity over Pt/mesoporous GaZSM-11 (Si/Ga = 94), which showed strong dependence on the conversion, reached 28.2%, whereas over corresponding mesoporous and conventional GaZSM-11catalysts reached 19.1% and 5.5%, respectively. A higher conversion and better selectivity can be attributed to the improved accessibility to the active extra-framework Ga species owing to the generation of mesopores inside the zeolite particles and shortening the contact time. It is worth mentioning that the prepared catalysts exhibited quite low activity in propane aromatization but exhibiting similar trends as for hexane aromatization. © 2011 Elsevier B.V. All rights reserved.

Evaluation of Zanthoxylum armatum Roxb for in vitro biological activities

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Fiaz Alam

2017-10-01

Full Text Available Zanthoxylum armatum fruits are used traditionally as a spice in various food preparations. The aim of this study was analysis of antimicrobial, cytotoxic, phytotoxic, insecticidal, and anti-leishmanial activity. The crude extract showed 86 ± 10% antifungal activity (Agar tube dilution method against Trichophyton longifusis while n-hexane, chloroform, and aqueous-methanol fractions inhibited this pathogen by 90 ± 7, 85 ± 10 and 70 ± 9% respectively. The n-hexane and aqueous-methanol fraction also, respectively, showed 40 ± 10 and 87 ± 9% inhibition of Microsporum canis. Chloroform fraction also displayed antifungal activity against Aspergillus flavus (60 ± 10% and aqueous-methanol fraction against F. solani (40 ± 8%. The crude ethanolic extract and its chloroform and aqueous-methanol fraction exhibited significant toxicity (Brine shrimps lethality assay against brine shrimps having LC50 value of 6.66 ± 1.1, 21.4 ± 3.3 and 29.6 ± 3.9 μg/ml, respectively. The crude ethanolic extract and its n-hexane soluble portion exhibited good anti-leishmanial activity (well serial dilution method each having IC50 values of 50 ± 5 μg/ml. The crude extract and various fractions possessed excellent herbicidal activity (Lemna minor assay, and caused more than 90% inhibition of the plant growth at 1000 μg/mL. The ethanolic extract, n-hexane and chloroform soluble portions caused 90% mortality in insecticidal activity (direct contact method of Rhyzopertha dominica. The ethanolic extract and its n-hexane soluble portion, respectively, caused 80 and 90% mortality of Callosobruchus analis. The present study showed that the tested fruit extracts of Z. armatum exhibited strong antifungal, cytotoxic, phytotoxic, insecticidal, and anti-leishmanial effects.

Toxicity of Turmeric Extracts to the Termite Reticulitermes flavipes (Blattodea: Rhinotermitidae).

Science.gov (United States)

Raje, Kapil R; Hughes, Gabriel P; Gondhalekar, Ameya D; Ginzel, Matthew D; Scharf, Michael E

2015-08-01

Turmeric is an important spice crop with documented human health benefits associated with chemicals called curcuminoids. In this study, the termite Reticulitermes flavipes (Kollar) was exposed to different solvent extracts of turmeric to investigate potential termiticidal properties. Treating termites with hexane extracts of purified lab-grade curcuminoids had no effect on termites. However, in continuous exposure assays, the LC(50) for hexane extracts of crude turmeric powder was 9.6 mg, or 1.0 mg starting material per square centimeter of filter paper substrate. These active components were soluble in a range of polar and apolar solvents, but only hexane could selectively fractionate active components away from the inactive curcuminoids. The active constituents of turmeric separated by thin layer chromatography (TLC) fluoresced in short-wave UV light but were not visible in long-wave UV light. By re-extracting TLC-separated bands in hexane and performing bioassays and gas chromatography-mass spectrometry, we demonstrated that termiticidal components of turmeric are extractable as a blend containing mainly ar-turmerone, turmerone, and curlone. This determination is consistent with findings of preceding work by other researchers that investigated insecticidal properties of turmeric in other pest insects. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Desolventizing of Jatropha curcas oil from azeotropes of solvents using ceramic membranes.

Science.gov (United States)

Carniel, Naira; Zabot, Giovani L; Paliga, Marshall; Mignoni, Marcelo L; Mazutti, Marcio A; Priamo, Wagner L; Oliveira, J V; Di Luccio, Marco; Tres, Marcus V

2017-12-01

The separation of Jatropha curcas oil from azeotropes of ethyl alcohol-n-hexane and isopropyl alcohol-n-hexane using ceramic membranes with different cutoffs (5, 10 and 20 kDa) is presented. The mass ratios of oil:azeotropes (O:S) studied were 1:3 for feeding pressures of 0.1, 0.2 and 0.3 MPa, and 1:1 for the feeding pressure of 0.1 MPa. Isopropyl alcohol was the best solvent for the membranes conditioning to permeate n-hexane (240 kg/m 2  h). In the separation of J. curcas oil and azeotropes of solvents, both membranes showed oil retention and total flux decreases with time. Overall, the lowest decrease in the retentions was reached in the 5 kDa membrane, while the lowest decrease in the total flux was reached in the 20 kDa. In the separation of oil and ethyl alcohol-n-hexane azeotrope, the best retention at 60 min of the process was equal to 17.3 wt% in the 20 kDa membrane at 0.3 MPa and O:S ratio equalled to 1:3. In this condition, the total permeate flux was 17.5 kg/m 2  h. Different retentions and permeabilities are provided when changing the O:S ratio, the feeding pressure and the molecular weight cutoff of membranes.

Biodiesel Production from Residual Palm Oil Contained in Spent Bleaching Earth by In Situ Trans-Esterification

Directory of Open Access Journals (Sweden)

A S Fahmil QRM

2014-06-01

Full Text Available Spent Bleaching Earth (SBE is an industrial solid waste of vegetable oil industry that has a high residual oil to be potentialy converted to biodiesel. This study aims at developing a biodiesel production process technology by utilizing residual palm oil contained in SBE and to test the use of hexane in the trans-esterification process. Optimization process was done by using the Response Surface Method (RSM. The variables studied included catalyst concentration and reaction time. On the other hand, the deoiled SBE resulted from biodiesel production was tested as an adsorbent on biodiesel purification after being reactivated. The method used in the biodiesel production included an in situ acid catalysed esterification followed by in situ base catalysed trans-esterification. The results of RSM showed that the optimum process was obtained at NaOH concentration of 1.8% and reaction time of 104.73 minutes, with a predicted response rate of 97.18% and 95.63% for validation results. The use of hexane could also increase the yield of biodiesel which was obtained on the ratio of hexane to methanol of 0.4:1 (volume of hexane: volume of methanol. On the other hand, the reactivated bleaching earth was effective as an adsorbent in biodiesel production, which was still conform with the Indonesian National Standard.

Cancer-suppressive potential of extracts of endemic plant Helichrysum zivojinii: effects on cell migration, invasion and angiogenesis.

Science.gov (United States)

Matić, Ivana Z; Aljancić, Ivana; Vajs, Vlatka; Jadranin, Milka; Gligorijević, Nevenka; Milosavljević, Slobodan; Juranić, Zorica D

2013-09-01

Helichrysum zivojinii Cernjavski & Soska is an endemic plant species that grows in the National Park Galicica in Macedonia. Five extracts were isolated as fractions from the aerial parts of the plant: a n-hexane extract (1), a dichloromethane extract (2), an ethyl-acetate extract (3), a n-butanol extract (4) and a methanol extract (5). A dose-dependent cytotoxic activity of the extracts on MDA-MB-231 and EA.hy926 cells was observed. Extracts exhibited more pronounced cytotoxic actions on MDA-MB-231 cells than on EA.hy926 cells. The n-hexane extract (1), at a non-toxic concentration, exhibited an inhibitory effect on the migration as well the invasiveness of MDA-MB-231 cells. The dichloromethane extract (2), at a non-toxic concentration, demonstrated inhibition of MDA-MB-231 cells invasion. Each of the five extracts applied at non-toxic concentrations inhibited migration of EA.hy926 cells. The prominent inhibitory effect of the n-hexane extract on EA.hy926 cells migration was associated with a notable anti-angiogenic action of this extract. The other four tested extracts demonstrated mild anti-angiogenic activity. Our data highlight the prominent anticancer potential of n-hexane (1) and dichloromethane (2) extracts, which could be attributed to their very pronounced and selective cytotoxic activities as well as their anti-invasive and anti-angiogenic properties.

Magnetic self-assembly for the synthesis of magnetically exchange coupled MnBi/Fe–Co composites

Energy Technology Data Exchange (ETDEWEB)

Xu, Xia [Department of Chemical and Biological Engineering and MINT Center, The University of Alabama, Tuscaloosa, AL 35487 (United States); Hong, Yang-Ki, E-mail: ykhong@eng.ua.edu [Department of Electrical and Computer Engineering and MINT Center, The University of Alabama, Tuscaloosa, AL 35487 (United States); Park, Jihoon; Lee, Woncheol [Department of Electrical and Computer Engineering and MINT Center, The University of Alabama, Tuscaloosa, AL 35487 (United States); Lane, Alan M. [Department of Chemical and Biological Engineering and MINT Center, The University of Alabama, Tuscaloosa, AL 35487 (United States); Cui, Jun [Energy and Environment Directorate, Pacific Northwestern National Laboratory, Richland, WA 99354 (United States)

2015-11-15

Exchange coupled hard/soft MnBi/Fe–Co core/shell structured composites were synthesized using a magnetic self-assembly process. MnBi particles were prepared by arc-melting, and Fe–Co nanoparticles were synthesized by an oleic acid assisted chemical reduction method. Grinding a mixture of micron-sized MnBi and Fe–Co nanoparticles in hexane resulted in MnBi/Fe–Co core/shell structured composites. The MnBi/Fe–Co (95/5 wt%) composites showed smooth magnetic hysteresis loops, enhanced remanent magnetization, and positive values in the ΔM curve, indicating exchange coupling between MnBi and Fe–Co particles. - Graphical abstract: Both MnBi and Fe–Co particles were dispersed in hexane for grinding. Because of the oleic acid used during the Fe–Co nanoparticle synthesis, they could be well dispersed in hexane. During the grinding, the size of MnBi particles was decreased, hexane was evaporated, and the Fe–Co nanoparticles were concentrated in the solvent and magnetically attracted by MnBi particles, forming a core/shell structure. - Highlights: • Exchange coupled MnBi/Fe–Co composites are synthesized through magnetic selfassembly. • Magnetic exchange coupling is demonstrated by smooth magnetic hysteresis loops, enhanced remanent magnetization, and dominant positive peak in the ΔM curve. • The experimental results in magnetic properties are close to the theoretical calculation results.

Inhibitory effect on in vitro LDL oxidation and HMG Co-A reductase activity of the liquid-liquid partitioned fractions of Hericium erinaceus (Bull.) Persoon (lion's mane mushroom).

Science.gov (United States)

Rahman, Mohammad Azizur; Abdullah, Noorlidah; Aminudin, Norhaniza

2014-01-01

Oxidation of low-density lipoprotein (LDL) has been strongly suggested as the key factor in the pathogenesis of atherosclerosis. Mushrooms have been implicated in having preventive effects against chronic diseases due especially to their antioxidant properties. In this study, in vitro inhibitory effect of Hericium erinaceus on LDL oxidation and the activity of the cholesterol biosynthetic key enzyme, 3-hydroxy-3-methyl glutaryl coenzyme A (HMG Co-A) reductase, was evaluated using five liquid-liquid solvent fractions consisting of methanol : dichloromethane (M : DCM), hexane (HEX), dichloromethane (DCM), ethyl acetate (EA), and aqueous residue (AQ). The hexane fraction showed the highest inhibition of oxidation of human LDL as reflected by the increased lag time (100 mins) for the formation of conjugated diene (CD) at 1 µg/mL and decreased production (68.28%, IC50 0.73 mg/mL) of thiobarbituric acid reactive substances (TBARS) at 1 mg/mL. It also mostly inhibited (59.91%) the activity of the HMG Co-A reductase at 10 mg/mL. The GC-MS profiling of the hexane fraction identified the presence of myconutrients: inter alia, ergosterol and linoleic acid. Thus, hexane fraction of Hericium erinaceus was found to be the most potent in vitro inhibitor of both LDL oxidation and HMG Co-A reductase activity having therapeutic potential for the prevention of oxidative stress-mediated vascular diseases.

Evaluation of antioxidant potentials of different solvent-fractions of Dialium indium (African Black velvet tamarind fruit pulp – in vitro

Directory of Open Access Journals (Sweden)

Olakunle Bamikole Afolabi

2018-02-01

Full Text Available Plant phytonutrients have been harnessed for their various curative properties both in vitro and in vivo. In this study African black velvet tamarind (ABVT fruit pulp was evaluated for it antioxidant potentials using chloroform and hexane fractions through different antioxidant parameters. In the results; total phenolic contents quantified in mg GAE/dried sample in chloroform and hexane extracts were; 14.57 ±5.85 and 9.78 ±4.61, total flavonoid contents in chloroform and hexane extracts as; 48.58 ±0.00 and 27.35 ±0.00 while the FRAP (µg AAE.g-1 dried sample was lower in chloroform (298.10 ±0.00 than hexane extracts (1029.81 ±0.00. More also, ability of varied concentrations of the extracts (with their IC50 to cause inhibition against Fe2+-induced MDA that was determined by TBARS in rat's brain and liver tissue homogenates, Fe2+-chelating ability and other antioxidant assays, showed an appreciable significant (p <0.05 difference. The various antioxidant properties showed by ABVT has indicated that, if the pulp is incorporated in diet, it could serve as an alternative in managing various ROS-induced degenerative ailments as it has been clearly demonstrated in the protection of brain and liver homogenates from Fe2+-induced oxidative stress. 

Characterization of some Jordanian oil shales by pyrolysis gas chromatography

International Nuclear Information System (INIS)

Jaradat, Q. M.

1995-01-01

Gas chromatography with flame ionization detector (GC-FID) was used to study pyrolysis of some Jordanian oil shale samples. Three sampls of different altitudes from El-Lajjun were studied. Pyrograms of solid sampls were studied at different temperature profiles. Solid-liquid extraction with water, methanol, or hexane allowed extraction of organics of different polarity. Hexane showed the highest extraction efficiency. Reproducibility of the pyrograms of the solid sample was evalualted. Relative standard deviation was 7.56%. (author). 7 refs., 8 figs

Untersuchungen zum atmosphärenchemischen Abbau langkettiger Aldehyde

OpenAIRE

Plagens, Heike

2001-01-01

In dieser Arbeit wurden die bimolekularen Geschwindigkeitskonstanten für die Reaktionen von Hexanal, Heptanal, Oktanal und Nonanal mit OH and Cl Radikalen bei (298 ± 2) K und (1000 ± 20) mbar experimentell bestimmt. Ebenso wurde die Chlorgeschwindigkeitskonstante für Butanal gemessen. Die Werte sind (in Einheiten von cm3 Molekül-1 s-1) in Tabelle 1 zusammengefaßt. Tabelle 1: Aldehyde kOH kCl Butanal - (2,21 ± 0,16) · 10-10 Hexan...

Green solvents and technologies for oil extraction from oilseeds

OpenAIRE

Kumar, S. P. Jeevan; Prasad, S. Rajendra; Banerjee, Rintu; Agarwal, Dinesh K.; Kulkarni, Kalyani S.; Ramesh, K. V.

2017-01-01

Oilseeds are crucial for the nutritional security of the global population. The conventional technology used for oil extraction from oilseeds is by solvent extraction. In solvent extraction, n-hexane is used as a solvent for its attributes such as simple recovery, non-polar nature, low latent heat of vaporization (330?kJ/kg) and high selectivity to solvents. However, usage of hexane as a solvent has lead to several repercussions such as air pollution, toxicity and harmfulness that prompted to...

Physicochemical characterisation of hexanic seed oil extract from ...

African Journals Online (AJOL)

Nyakudya, Trevor

2013-02-20

Feb 20, 2013 ... Erlwanger4, Mazuru B. Gundidza5, Michael L. Magwa6 and Perkin Muredzi7 ... possess several physiological side effects, hence the .... Physical and chemical properties of S. molle seed oil ..... composition of Schinus molle essential oil and its cytotoxic activity on ... cultivars (Linum usitatissimum L.). Gen.

hexane extracts of the husk of Cocos nucifera

African Journals Online (AJOL)

Jane

2011-04-25

Apr 25, 2011 ... (Esquenazi, 2002) and in India, heating the coconut shells gives ... MATERIALS AND METHODS ... sterilized molten Mueller-Hinton agar at 40°C to give final .... and 8 h, respectively, and transferred to 4.5 ml of nutrient broth.

Ovicidal Activity of Couroupita guianensis (Aubl. against Spodoptera litura (Fab.

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Kathirvelu Baskar

2014-01-01

Full Text Available Hexane, chloroform, and ethyl acetate extracts of Couroupita guianensis leaves were studied for ovicidal activity against S. litura. All the extracts showed ovicidal activity against S. litura. Maximum activity was noticed in hexane extract and it showed the least LC50 and LC90 values; the regression equation was also higher than the other extracts. All the analyzed values showed homogeneity variance. The active hexane extract was fractionated and eight fractions were isolated. The fractions were studied at different concentrations. Among the fractions, fraction 8 showed maximum ovicidal activity with least LC50 and LC90 values. Fraction 8 differed statistically from the other fractions; the regression equation value was higher than the other fractions. All the P values obtained from regression analysis were significant. The results of the present investigation clearly suggest that the active fraction could be purified to isolate active compound(s and could be used to develop an insecticidal formulation to control economically important agricultural pests.

Phytochemical and in vitro screening of some Ficus and Morus spp. for hypolipidaemic and antioxidant activities and in vivo assessment of Ficus mysorensis (Roth).

Science.gov (United States)

Awad, Nagwa E; Seida, Ahmed A; Hamed, Manal A; Mahmoud, Ahlam H; Elbatanony, Marwa M

2012-01-01

Phytochemical screening of air-dried leaves and fruit juice of certain Ficus and Morus spp. have been studied. In an in vitro study, the ethanol and hexane extracts of the investigated plants were evaluated against hyperlipidaemia by estimating the rate limiting enzyme of cholesterol biothenysis; β-hydroxy-β-methylglutaryl coenzyme A reductase (HMG-CoA reductase). The antioxidant activity was evaluated by reduction of DPPH(-) free radical. Extra phytochemical screening of Ficus extracts was undertaken, which recorded potent hypolipidaemic and antioxidant activities. The more pronounced extract, Ficus mysorensis (hexane extract), was evaluated in vivo by estimation of the lipid profile and certain antioxidant parameters in hypercholesterolemic rats. The hexane fraction was chromatographed and six isolated compounds were identified. Furthermore, its saponifiable fraction was identified by a MS/MS technique. In conclusion, F. mysorensis recorded hypolipidaemic and antioxidant effects. Detailed studies of the isolated compounds must be undertaken for an evaluation against hypercholesterolemia and free radical elevation.

The effect of Artemisia annua on broiler performance, on intestinal microbiota and on the course of a Clostridium perfringens infection applying a necrotic enteritis disease model

DEFF Research Database (Denmark)

Engberg, Ricarda M; Grevsen, Kai; Ivarsen, Elise

2012-01-01

The aerial parts of the plant Artemisia annua contain essential oils having antimicrobial properties against Clostridium perfringens Type A, the causal agent for necrotic enteritis in broilers. In two experiments, the influence of increasing dietary concentrations of dried A. annua leaves (0, 5, 10...... and 20 g/kg) and n-hexane extract from fresh A. annua leaves (0, 125, 250 and 500 mg/kg) on broiler performance was investigated. Dried plant material decreased feed intake and body weight in a dose-dependent manner, and 10 and 20 g/kg diet tended to improve the feed conversion ratio. The n...... the effect of the dietary addition of dried A. annua leaves (10 g/kg on top) or n-hexane extract of A. annua (250 mg/kg) on the severity of the disease in broilers. The addition of n-hexane extract reduced the intestinal C. perfringens numbers and the severity of the disease-related small intestinal lesions...

Phytochemistry, cytotoxicity and antiviral activity of Eleusine indica (sambau)

Science.gov (United States)

Iberahim, Rashidah; Yaacob, Wan Ahmad; Ibrahim, Nazlina

2015-09-01

Goose grass also known as Eleusine indica (EI) is a local medicinal plant that displays antioxidant, antimicrobial and anticancer activities. The present study is to determine the phytochemical constituents, cytotoxicity and antiviral activities for both crude extract and fraction obtained from the plant. The crude extract contained more secondary metabolites compared to the hexane fraction as gauged using standard phytochemical tests. Cytotoxicity screening against Vero cells using MTT assay showed that the CC50 values for crude extract and hexane fraction were 2.07 and 5.62 mg/ml respectively. The antiviral activity towards Herpes Simplex Virus type 1 (HSV-1) was determined using plaque reduction assay. The selective indices (SI = CC50 / EC50) for both methanol extract and hexane fraction were 12.2 and 6.2 respectively. These results demonstrate that the extract prepared from E. indica possesses phytochemical compound that was non cytotoxic to the cell with potential antiviral activity.

Antimicrobial activity of Aegiphila sellowiana Cham., Lamiaceae, against oral pathogens

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Marcele A. Ferreira

Full Text Available The antimicrobial activity of Aegiphila sellowiana Cham., Lamiaceae, against oral pathogens is reported. The Minimal Inhibitory Concentrations (MICs for inhibiting the microorganisms growth were determined using the broth microdilution method from the CLSI M7-A7 protocol. Chlorhexidine was used as the positive control. The ethanol crude extract of the aerial parts of A. sellowiana exhibited activity against the microorganisms tested in this work; however, the activity decreased after partition with n-hexane, dichloromethane, and ethyl acetate. Among the tested fractions, the n-hexane fraction was found to be the most effective against the evaluated oral pathogens. GC-MS analysis of this latter fraction revealed that fatty acids esters, steroids, and aliphatic sesquiterpene hydrocarbons are its major constituents. These compounds may be responsible for the activity of the n-hexane fraction, but other chemical constituents of the dichloromethane, ethyl acetate, and hydroalcoholic fraction may potentialize their activities in the crude extract.

Phytotoxic potential of Drimys brasiliensis Miers for use in weed control

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Simoni Anese

2015-10-01

Full Text Available This study aims to evaluate the phytotoxicity potential of leaf and root extracts of Drimys brasiliensis on the germination and seedling growth of Panicum maximum and Euphorbia heterophylla and its influence on metaxylem cell size in the seedling roots of the latter specie. The leaf and root extracts were fractionated by partition chromatography, and the hexane and ethyl acetate fractions obtained from each organ were evaluated at different concentrations for phytotoxic activity in several bioassays. In seedling growth tests, we compared the effects of these fractions with the herbicide oxyfluorfen. The hexane fraction of the root extracts showed a higher inhibitory potential on the germination and growth of weeds and reduced the average size of the metaxylem cells of E. heterophylla roots by more than 50%.The inhibitory effects of the root hexane fraction on seedling growth was similar to the herbicide, indicating that D. brasiliensis is a possible alternative form of control for the weed species examined.

Optimizing the Production of Biodiesel Using Lipase Entrapped in Biomimetic Silica

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Chi-Yang Yu

2013-04-01

Full Text Available We entrapped lipase from Pseudomonas cepacia in polyallylamine-mediated biomimetic silica, and then applied entrapped lipase to the synthesis of biodiesel with soybean oil or waste cooking oil as a feedstock. The effects of reaction temperature, substrate molar ratio (methanol/oil and n-hexane content (w/w of oil were evaluated using response surface methodology (RSM combined with Box-Behnken design. The optimal reaction conditions for soybean oil were 43.6 °C, substrate molar ratio of 4.3%, and 75% n-hexane. The predicted and experimental values of biodiesel conversion were 79% and 76%, respectively. The optimal reaction conditions for waste cooking oil were 43.3 °C, substrate molar ratio of 5%, and 38% n-hexane. The predicted and experimental values of conversion were 68% and 67%, respectively. The conversion efficiency remained the same even after 1-month storage of entrapped lipase at 4 °C or room temperature.

THE EFFECTIVENES OF ETANOL EXTRACT, PARTITION N-HEKSANA, AND CROMATHOGRAPHY FRACTION OF MOMORDICA CHARANTIA L. TO LOWER BLOOD GLUCOSE LEVEL

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Ni Luh Putu Kusuma Clara Dewinda

2017-08-01

Full Text Available This study aims to determine the effectiveness of the ethanol extract, partition n-hexane, and chromatography fractions Momordica charantia L. in lowering blood glucose levels in experimental diabetic male rats.  This study used 25 male rats were divided into five treatment groups P0 (negative control, P1 (positive control, P2 (ethanol extract, P3 (partition n-hexane, and P4 (chromatographic fraction the variable observed glucose levels blood for 21 days. Blood glucose levels were analyzed on days -1, 0, 4, 11, 18. The bill, which is used in the form of a completely randomized design (CRD. The data obtained and analyzed by using Split in Time. The results showed of giving chromatographic fractions bitter melon 50 mg / kg body weight can reduce blood glucose levels in hyperglycemic rats better than the ethanol extract 200 mg / kg body weight and partition n-hexane 50 mg / kg body weight.

Toxicity of Boswellia dalzielii (Burseraceae) Leaf Fractions Against Immature Stages of Anopheles gambiae (Giles) and Culex quinquefasciatus (Say) (Diptera: Culicidae)

Science.gov (United States)

Younoussa, Lame; Nukenine, Elias Nchiwan; Esimone, Charles Okechukwu

2016-01-01

Mosquitoes are vectors of several human pathogens, and great attention has recently been placed on insecticides from plant-derived products, in search for mosquito control agents. This study, thus, investigated the potency of Boswellia dalzielii methanol leaf extract and its four fractions as mosquito ovicide, larvicide, and pupicide against Anopheles gambiae and Culex quinquefasciatus. The plant products were tested at the following concentrations: 125, 250, 500, 1000, and 2000 ppm on eggs and 312.5, 625, 1250, and 2500 ppm on the larvae and pupae of the mosquitoes. For results, hatchability of A. gambiae eggs was reduced to 5% with n-hexane fraction at 2000 ppm. Among the plant products tested, n-hexane fraction was most toxic against A. gambiae (LC50 = 385.9 ppm) and C. quinquefasciatus (LC50 = 3394.9 ppm). The n-hexane fraction of B. dalzielii might be used as a mosquitocidal agent in the breeding sites of A. gambiae and C. quinquefasciatus. PMID:27279752

Toxicity of (Burseraceae Leaf Fractions against Immature Stages of (Giles and (Say (Diptera: Culicidae

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Lame Younoussa

2016-01-01

Full Text Available Mosquitoes are vectors of several human pathogens, and great attention has recently been placed on insecticides from plant-derived products, in search for mosquito control agents. This study, thus, investigated the potency of Boswellia dalzielii methanol leaf extract and its four fractions as mosquito ovicide, larvicide, and pupicide against Anopheles gambiae and Culex quinquefasciatus . The plant products were tested at the following concentrations: 125, 250, 500, 1000, and 2000 ppm on eggs and 312.5, 625, 1250, and 2500 ppm on the larvae and pupae of the mosquitoes. For results, hatchability of A. gambiae eggs was reduced to 5% with n -hexane fraction at 2000 ppm. Among the plant products tested, n -hexane fraction was most toxic against A. gambiae (LC 50 = 385.9 ppm and C. quinquefasciatus (LC 50 = 3394.9 ppm. The n -hexane fraction of B. dalzielii might be used as a mosquitocidal agent in the breeding sites of A. gambiae and C. quinquefasciatus .

Biodiesel synthesis by direct transesterification of microalga Botryococcus braunii with continuous methanol reflux.

Science.gov (United States)

Hidalgo, Pamela; Ciudad, Gustavo; Schober, Sigurd; Mittelbach, Martin; Navia, Rodrigo

2015-04-01

Direct transesterification of Botryococcus braunii with continuous acyl acceptor reflux was evaluated. This method combines in one step lipid extraction and esterification/transesterification. Fatty acid methyl esters (FAME) synthesis by direct conversion of microalgal biomass was carried out using sulfuric acid as catalyst and methanol as acyl acceptor. In this system, once lipids are extracted, they are contacted with the catalyst and methanol reaching 82%wt of FAME yield. To optimize the reaction conditions, a factorial design using surface response methodology was applied. The effects of catalyst concentration and co-solvent concentration were studied. Hexane was used as co-solvent for increasing lipid extraction performance. The incorporation of hexane in the reaction provoked an increase in FAME yield from 82% (pure methanol) to 95% when a 47%v/v of hexane was incorporated in the reaction. However, the selectivity towards non-saponifiable lipids such as sterols was increased, negatively affecting biodiesel quality. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assessment of Adiantum incisum, Alternanthera pungens and Trichodesma indicum as bio-insecticides against stored grain pests

International Nuclear Information System (INIS)

Safdar, N.; Yasmin, A.

2017-01-01

This study investigated the insecticidal potential of Adiantum incisum Forssk (Pteridaceae), Alternanthera pungens Kunth (Amaranthaceae) and Trichodesma indicum L. (Boraginaceae). Aqueous, methanolic and n-hexane extracts of whole plants (roots, stem and leaves) were prepared using maceration technique. Insecticidal activities of aqueous, methanolic and n-hexane extracts of three plants (10, 20 and 30 mg/mL) were evaluated by impregnated filter paper insecticidal assay. Methanol and hexane extracts of Adiantum incisum gave effective LD 50 (15.3 mg/mL) against Callosobruchus chinensis and Sitophilus oryzae (LD5022 mg/mL) after 24 hours respectively. Present research elucidates the important phytochemicals (alkaloids, saponins and tannins) in three plants by FTIR and good insecticidal activity (LD50 < 25 mg/mL in 24 hours) against Callosobruchus chinensis and Sitophilus oryzae. Current study promotes further investigations for using these plant extracts as anti-feedants, repellents, fumigants and formulation of non-toxic bio-insecticides. (author)

Anti-inflammatory activity of Lippia dulcis.

Science.gov (United States)

Pérez, S; Meckes, M; Pérez, C; Susunaga, A; Zavala, M A

2005-10-31

Lippia dulcis hexane and ethanol extracts were tested for its anti-inflammatory activity in several animal models. Hexane extract showed to be inactive, but the ethanol extract at doses of 400 mg/kg produced significant inhibition of carrageenan-induced paw oedema and reduced the weight of cotton pellet-induced granuloma, moreover, the topical application of 0.5 mg/ear of this extract inhibited the edema induced with TPA by 49.13%, an effect which is of less intensity than that produced by indomethacine at the same dose.

Can crystal engineering be as beneficial as micronisation and overcome its pitfalls?: A case study with cilostazol.

Science.gov (United States)

Sai Gouthami, Kodukula; Kumar, Dinesh; Thipparaboina, Rajesh; Chavan, Rahul B; Shastri, Nalini R

2015-08-01

Improvement in dissolution of the drugs having poor solubility is a challenge in pharmaceutical industry. Micronization is one technique, employed for dissolution enhancement of cilostazol, a BCS class II drug. However, the obtained micronized drug possesses poor flowability. The aim of this study was to improve the dissolution rate and flow properties of cilostazol by crystal engineering, using habit modification method and compare with micronized cilostazol bulk drug. Simulation studies were performed to predict the effect of solvents on cilostazol crystal habit. Cilostazol crystals with different habits were prepared by solvent:anti-solvent crystallization technique. SEM, FTIR, DSC, TGA and PXRD were used for solid state characterization. The results revealed that cilostazol re-crystallized from methanol-hexane system were hexagonal and ethanol-hexane system gave rods. Cilostazol engineered habits showed increased dissolution rate than unprocessed drug but similar dissolution rate when compared to micronized cilostazol. Micronized cilostazol showed a dissolution efficiency of 75.58% where as cilostazol recrystallized from methanol-hexane and ethanol-hexane systems resulted in a dissolution efficiency of 72.63% and 68.63%, respectively. In addition, crystal engineering resulted in improved flow properties of re-crystallized habits when compared to micronized form of the drug. In conclusion, crystal engineering by habit modification show potential for dissolution enhancement with an added advantage of improved flow properties over micronization technique, for poorly soluble drugs like cilostazol. Copyright © 2015 Elsevier B.V. All rights reserved.

Preferential methanogenic biodegradation of short-chain n-alkanes by microbial communities from two different oil sands tailings ponds.

Science.gov (United States)

Mohamad Shahimin, Mohd Faidz; Foght, Julia M; Siddique, Tariq

2016-05-15

Oil sands tailings ponds harbor diverse anaerobic microbial communities capable of methanogenic biodegradation of solvent hydrocarbons entrained in the tailings. Mature fine tailings (MFT) from two operators (Albian and CNRL) that use different extraction solvents were incubated with mixtures of either two (n-pentane and n-hexane) or four (n-pentane, n-hexane, n-octane and n-decane) n-alkanes under methanogenic conditions for ~600 d. Microbes in Albian MFT began methane production by ~80 d, achieving complete depletion of n-pentane and n-hexane in the two-alkane mixture and their preferential biodegradation in the four-alkane mixture. Microbes in CNRL MFT preferentially metabolized n-octane and n-decane in the four-alkane mixture after a ~80 d lag but exhibited a lag of ~360 d before commencing biodegradation of n-pentane and n-hexane in the two-alkane mixture. 16S rRNA gene pyrosequencing revealed Peptococcaceae members as key bacterial n-alkane degraders in all treatments except CNRL MFT amended with the four-alkane mixture, in which Anaerolineaceae, Desulfobacteraceae (Desulfobacterium) and Syntrophaceae (Smithella) dominated during n-octane and n-decane biodegradation. Anaerolineaceae sequences increased only in cultures amended with the four-alkane mixture and only during n-octane and n-decane biodegradation. The dominant methanogens were acetoclastic Methanosaetaceae. These results highlight preferential n-alkane biodegradation by microbes in oil sands tailings from different producers, with implications for tailings management and reclamation. Copyright © 2016 Elsevier B.V. All rights reserved.

Improving gasoline quality produced from MIDOR light naphtha isomerization unit

Directory of Open Access Journals (Sweden)

M.F. Mohamed

2017-03-01

Full Text Available Isomerization process became one of the best gasoline production sources, as it gives a high octane product while saving environment from pollution impacts. This paper presents a practical study that aims to improve the gasoline quality and economic income of an existing light naphtha isomerization unit used for octane improvement. The study included selecting the optimum combination of isomerization unit equipment that gives better product specifications for a specified feed. Eight scenarios were studied and simulated to predict the product specs. The original studied unit is MIDOR light naphtha isomerization unit at Alexandria-Egypt that recycles the unconverted hexane (C6. The other studied scenarios were adding fractionators for separating feed iso-pentanes, and recycling unconverted pentanes, hexanes and/or combinations of these fractionators. The results show a change in octane number of gasoline product for a specific feed. Once through process with no extra fractionators has lower octane number of 81 while that with de-iso-pentanizer–de-pentanizer and de-hexanizer produces gasoline with 92.3 octane number. Detailed economic study was done to calculate the return on investment “ROI” for each process option based on equipment, utilities, feed and product prices. Once through simple isomerization unit had the lowest ROI of 14.3% per year while the combination of De-iso-pentanizer with the De-hexanizer had the best ROI of 26.6% per year.

Chemical composition, toxicity and larvicidal and antifungal activities of Persea americana (avocado) seed extracts.

Science.gov (United States)

Leite, João Jaime Giffoni; Brito, Erika Helena Salles; Cordeiro, Rossana Aguiar; Brilhante, Raimunda Sâmia Nogueira; Sidrim, José Júlio Costa; Bertini, Luciana Medeiros; Morais, Selene Maia de; Rocha, Marcos Fábio Gadelha

2009-01-01

The present study had the aim of testing the hexane and methanol extracts of avocado seeds, in order to determine their toxicity towards Artemia salina, evaluate their larvicidal activity towards Aedes aegypti and investigate their in vitro antifungal potential against strains of Candida spp, Cryptococcus neoformans and Malassezia pachydermatis through the microdilution technique. In toxicity tests on Artemia salina, the hexane and methanol extracts from avocado seeds showed LC50 values of 2.37 and 24.13 mg mL-1 respectively. Against Aedes aegypti larvae, the LC50 results obtained were 16.7 mg mL-1 for hexane extract and 8.87 mg mL-1 for methanol extract from avocado seeds. The extracts tested were also active against all the yeast strains tested in vitro, with differing results such that the minimum inhibitory concentration of the hexane extract ranged from 0.625 to 1.25mg L-(1), from 0.312 to 0.625 mg mL-1 and from 0.031 to 0.625 mg mL-1, for the strains of Candida spp, Cryptococcus neoformans and Malassezia pachydermatis, respectively. The minimal inhibitory concentration for the methanol extract ranged from 0.125 to 0.625 mg mL-1, from 0.08 to 0.156 mg mL-1 and from 0.312 to 0.625 mg mL-1, for the strains of Candida spp., Cryptococcus neoformans and Malassezia pachydermatis, respectively.

Inhibitory Effect on In Vitro LDL Oxidation and HMG Co-A Reductase Activity of the Liquid-Liquid Partitioned Fractions of Hericium erinaceus (Bull. Persoon (Lion’s Mane Mushroom

Directory of Open Access Journals (Sweden)

Mohammad Azizur Rahman

2014-01-01

Full Text Available Oxidation of low-density lipoprotein (LDL has been strongly suggested as the key factor in the pathogenesis of atherosclerosis. Mushrooms have been implicated in having preventive effects against chronic diseases due especially to their antioxidant properties. In this study, in vitro inhibitory effect of Hericium erinaceus on LDL oxidation and the activity of the cholesterol biosynthetic key enzyme, 3-hydroxy-3-methyl glutaryl coenzyme A (HMG Co-A reductase, was evaluated using five liquid-liquid solvent fractions consisting of methanol : dichloromethane (M : DCM, hexane (HEX, dichloromethane (DCM, ethyl acetate (EA, and aqueous residue (AQ. The hexane fraction showed the highest inhibition of oxidation of human LDL as reflected by the increased lag time (100 mins for the formation of conjugated diene (CD at 1 µg/mL and decreased production (68.28%, IC50 0.73 mg/mL of thiobarbituric acid reactive substances (TBARS at 1 mg/mL. It also mostly inhibited (59.91% the activity of the HMG Co-A reductase at 10 mg/mL. The GC-MS profiling of the hexane fraction identified the presence of myconutrients: inter alia, ergosterol and linoleic acid. Thus, hexane fraction of Hericium erinaceus was found to be the most potent in vitro inhibitor of both LDL oxidation and HMG Co-A reductase activity having therapeutic potential for the prevention of oxidative stress-mediated vascular diseases.

Excited state Intramolecular Proton Transfer in Anthralin

DEFF Research Database (Denmark)

Møller, Søren; Andersen, Kristine B.; Spanget-Larsen, Jens

1998-01-01

Quantum chemical calculations performed on anthralin (1,8-dihydroxy-9(10H)-anthracenone) predict the possibility of an excited-state intramolecular proton transfer process. Fluorescence excitation and emission spectra of the compound dissolved in n-hexane at ambient temperature results in an unus......Quantum chemical calculations performed on anthralin (1,8-dihydroxy-9(10H)-anthracenone) predict the possibility of an excited-state intramolecular proton transfer process. Fluorescence excitation and emission spectra of the compound dissolved in n-hexane at ambient temperature results......, associated with an excited-state intramolecular proton transfer process....

Design of Separation Processes with Ionic Liquids

DEFF Research Database (Denmark)

Peng-noo, Worawit; Kulajanpeng, Kusuma; Gani, Rafiqul

2015-01-01

A systematic methodology for screening and designing of Ionic Liquid (IL)-based separation processes is proposed and demonstrated using several case studies of both aqueous and non-aqueous systems, for instance, ethanol + water, ethanol + hexane, benzene + hexane, and toluene + methylcyclohexane....... The best four ILs of each mixture are [mmim][dmp], [emim][bti], [emim][etso4] and [hmim][tcb], respectively. All of them were used as entrainers in the extractive distillation. A process simulation of each system was carried out and showed a lower both energy requirement and solvent usage as compared...

Synergistic Extraction of Lactic Acid with Tri-n-Octylamine and Try-n-Butylphosphate

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, Michiaki.; Yuba, Seiji.; Kondo, Kazuo. (Doshisha University, Department of Chemical Engineering and Materials Science (Japan))

1998-12-01

Synergistic extraction system of lactic acid is examined to develop to in situ extractive fermentation process. The addition of try-n-butyl phosphate(TBP) to the extraction system of lactic acid(HA) with tri-n-actylamine(TOA) diluted by hexane causes a large synergism. Extraction reaction with the mixed extractant is interpreted quite well based on the formation of mixed complex, HA[center dot]TOA[center dot]2TBP. Though the addition of hexane solution containing TBP and TOA to the culture of Lactobacillus rhamnosus results in low lactate production, some lactate is produced. (author)

Synergistic Extraction of Lactic Acid with Tri-n-Octylamine and Try-n-Butylphosphate

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, Michiaki.; Yuba, Seiji.; Kondo, Kazuo. [Doshisha University, Department of Chemical Engineering and Materials Science (Japan)

1998-12-01

Synergistic extraction system of lactic acid is examined to develop to in situ extractive fermentation process. The addition of try-n-butyl phosphate(TBP) to the extraction system of lactic acid(HA) with tri-n-actylamine(TOA) diluted by hexane causes a large synergism. Extraction reaction with the mixed extractant is interpreted quite well based on the formation of mixed complex, HA{center_dot}TOA{center_dot}2TBP. Though the addition of hexane solution containing TBP and TOA to the culture of Lactobacillus rhamnosus results in low lactate production, some lactate is produced. (author)

Chemical characterization using gas chromatography/mass spectrometry of two extracts from Phyllanthus orbicularis HBK

International Nuclear Information System (INIS)

Gutierrez Gaiten, Yamilet Irene; Miranda Martinez, Migdalia; Bello Alarcon, Adonis

2011-01-01

The objective of this paper was the chemical characterization of two extracts from Phyllanthus orbicularis HBK through gas chromatography/mass spectrometry. To this end, maceration with N-hexane and ethyl acetate was used to obtain the respective extracts. The study of the hexane extract identified 17 components in which hydrocarbonate structures prevailed, mainly cyclooctacosane. In the ethyl acetate extract, 19 compounds were detected, being the terpenoids the predominant, although the most abundant was sterol g-sitosterol. For the first time, the identified compounds are reported for this species

Antimycobacterial activity of medicinal plants used by the Mayo people of Sonora, Mexico.

Science.gov (United States)

Coronado-Aceves, Enrique Wenceslao; Sánchez-Escalante, José Jesús; López-Cervantes, Jaime; Robles-Zepeda, Ramón Enrique; Velázquez, Carlos; Sánchez-Machado, Dalia Isabel; Garibay-Escobar, Adriana

2016-08-22

Tuberculosis (TB) is an infectious disease mainly caused by Mycobacterium tuberculosis (Mtb), which generates 9 million new cases worldwide each year. The Mayo ethnicity of southern Sonora, Mexico is more than 2000 years old, and the Mayos possess extensive knowledge of traditional medicine. To evaluate the antimycobacterial activity levels of extracts of medicinal plants used by the Mayos against Mtb and Mycobacterium smegmatis (Msm) in the treatment of TB, respiratory diseases and related symptoms. A total of 34 plant species were collected, and 191 extracts were created with n-hexane, dichloromethane, ethyl acetate (EtOAc), methanol and water. Their minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined against Mtb H37Rv using the microplate alamar blue assay (MABA) and against Msm using the resazurin microplate assay (REMA) at 6 and 2 days of exposure, respectively, and at concentrations of 250-1.9µg/mL (n-hexane extracts) and 1000-7.81µg/mL (extracts obtained with dichloromethane, EtOAc, methanol and water). Rhynchosia precatoria (Willd.) DC. (n-hexane root extract), Euphorbia albomarginata Torr. and A. Gray. (EtOAc shoot extract) and Helianthus annuus L. (n-hexane stem extract) were the most active plants against Mtb H37Rv, with MICs of 15.6, 250, 250µg/mL and MBCs of 31.25, 250, 250µg/mL, respectively. R. precatoria (root) was the only active plant against Msm, with MIC and MBC values of ≥250µg/mL. None of the aqueous extracts were active. This study validates the medicinal use of certain plants used by the Mayo people in the treatment of TB and related symptoms. R. precatoria, E. albomarginata and H. annuus are promising plant sources of active compounds that act against Mtb H37Rv. To our knowledge, this is the first time that their antimycobacterial activity has been reported. Crude extracts obtained with n-hexane, EtOAc and dichloromethane were the most active against Mtb H37Rv. Copyright © 2016

Mixed-Penetrant Sorption in Ultra-Thin Films of Polymer of Intrinsic Microporosity PIM-1

KAUST Repository

Ogieglo, Wojciech; Furchner, Andreas; Ghanem, Bader; Ma, Xiao-Hua; Pinnau, Ingo; Wessling, Matthias

2017-01-01

Mixed penetrant sorption into ultra-thin films of a super-glassy polymer of intrinsic microporosity (PIM-1) was studied for the first time by using interference-enhanced in-situ spectroscopic ellipsometry. PIM-1 swelling and the concurrent changes in its refractive index were determined in ultra-thin (12 - 14 nm) films exposed to pure and mixed penetrants. The penetrants included water, n-hexane and ethanol and were chosen based on their significantly different penetrant-penetrant and penetrant-polymer affinities. This allowed studying microporous polymer responses at diverse ternary compositions and revealed effects such as competition for the sorption sites (for water / n-hexane or ethanol / n-hexane) or enhancement in sorption of typically weakly sorbing water in the presence of more highly sorbing ethanol. The results reveal details of the mutual sorption effects which often complicate comprehension of glassy polymers' behavior in applications such as high-performance membranes, adsorbents or catalysts. Mixed-penetrant effects are typically very challenging to study directly and their understanding is necessary owing to a broadly recognized inadequacy of simple extrapolations from measurements in pure component environment.

Effect of Trifolium sp. Flowers extracts on the Status of Liver Histology of Streptozotocin-induced Diabetic Rats

International Nuclear Information System (INIS)

AlRawi, Maisaa M.

2007-01-01

The present study deals with the effect of (water, hexane and ethanol) extracts prepared from the flower head of clover flowers (CF) (Trifolium alexandrinum), in the treatment of diabetes induced experimentally by streptozotocin (STZ) in male rats. More than fifty percent of diabetic rats were died by 48 hours post streptozotocin injection. A single dose of STZ (50mg/kg body weight) induced destruction of the liver architecture, cytoplasmic vacuolation of the hepatocytes and nuclei of many cells revealed clear signs of necrosis, leucocytic infiltration, liver fibrosis and fatty infiltration. Moreover, Dilatation and inflammation in central vein and blood vessels, the portal veins appeared congested with blood with fibrosis and leucocytic infiltration around it. After treatment with water, hexan and ethanol extracts of CF remarkable improvement in histological structure of liver sections of diabetic rats, the water extract is more potent than hexane and ethanol extracts. Thus, the result of the present study provides a scientific rationale for the use of Trifolium alexandrinum as promising antidiabetic agent. (author)

Toxicity of Piper aduncum L. (Piperales: Piperaceae) from the Amazon forest for the cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae).

Science.gov (United States)

Silva, Wilson Castro; Martins, João Ricardo de Souza; de Souza, Hellen Emília Menezes; Heinzen, Horacio; Cesio, Maria Verônica; Mato, Mauricio; Albrecht, Francine; de Azevedo, João Lúcio; de Barros, Neiva Monteiro

2009-10-14

The mortality of 14-21-day-old Rhipicephalus (Boophilus) microplus larvae, and the mortality and fertility of groups of engorged adult females exposed to different concentrations of hexane, ethyl acetate and ethanol extracts of spiked pepper (Piper aduncum) were evaluated, using a completely randomized design with five treatment groups, two control groups, and two replicates for the larvae and five replicates for the adult females. Similar methodology was used to investigate the toxicity of the essential oil hydro-distillate (94.84% dillapiole) obtained from the P. aduncum crude hexane extract. The LC(50) of the hexane extract was 9.30 mg ml(-1) for larvae and the reproduction reduction ranged from 12.48% to 54.22%, while 0.1mg/ml(-1) of the essential oil induced 100% mortality in larvae. Literature reports on natural products active against R. microplus were listed and compared with the results presented here. These results indicate that P. aduncum extracts, and particularly its essential oil, are potential alternative control agents for R. microplus.

Screening of metabolites secondary compounds in extract of moringa fruit and determination of inhibitory effect on growth of the fungus Candida albicans

Science.gov (United States)

Nuryanti, Siti; Puspitasari, Dwi Juli

2017-08-01

Moringa (Moringa oleifera Lamk) is a nutritious plant that can cure various diseases. Parts of this plant like leave, root, flower, and fruit can be used as a traditional medicine. The research about screening of secondary metabolites in moringa extracts and the determination of their inhibitory effect on growth of the fungus Candida albicans have been done. This research was conducted by extracting the moringa fruit with various solvent with different polarity namely hexane, distilled water and ethanol. The fungal inhibition test was done by well-difuse method. Suspensions of Candida albicans was standardized by 0.5 Mc Farland standard. The results showed that the extracts of Moringa with distilled water provided the greatest inhibition on the growth of the fungus Candida albicans compared to moringa fruit extracted by ethanol and hexane. The percentages inhibition of Moringa extracts on the growth of the Candida albicans with distilled water, ethanol and hexane solvents were 89.90%, 57.90% and 8.97% respectively. Phytochemical screening test showed that the moringa fruit contain alkaloids, flavonoids and steroids.

Poly(ethylene oxide) surfactant polymers.

Science.gov (United States)

Vacheethasanee, Katanchalee; Wang, Shuwu; Qiu, Yongxing; Marchant, Roger E

2004-01-01

We report on a series of structurally well-defined surfactant polymers that undergo surface-induced self-assembly on hydrophobic biomaterial surfaces. The surfactant polymers consist of a poly(vinyl amine) backbone with poly(ethylene oxide) and hexanal pendant groups. The poly(vinyl amine) (PVAm) was synthesized by hydrolysis of poly(N-vinyl formamide) following free radical polymerization of N-vinyl formamide. Hexanal and aldehyde-terminated poly(ethylene oxide) (PEO) were simultaneously attached to PVAm via reductive amination. Surfactant polymers with different PEO:hexanal ratios and hydrophilic/hydrophobic balances were prepared, and characterized by FT-IR, 1H-NMR and XPS spectroscopies. Surface active properties at the air/water interface were determined by surface tension measurements. Surface activity at a solid surface/water interface was demonstrated by atomic force microscopy, showing epitaxially molecular alignment for surfactant polymers adsorbed on highly oriented pyrolytic graphite. The surfactant polymers described in this report can be adapted for simple non-covalent surface modification of biomaterials and hydrophobic surfaces to provide highly hydrated interfaces.

Non-chromatographic radioimmunoassay for serum dehydroepiandrosterone using a mixture of antisera

International Nuclear Information System (INIS)

Sekihara, H.; Ohsawa, N.

1974-01-01

A simplified method for evaluating serum dehydroepiandrosterone (DHEA) without chromatography was developed, using mixtures of two different anti-DHEA antisera, anti-3β-hydroxy-Δ 5 antiserum and anti-11-deoxy-17-ketosteroid antiserum, in which cross-reactivity of each antiserum is reduced to a negligible amount. Serum (20 μl) was extracted with 1 ml of n-hexane. One milliliter of 80 percent methanol was added to the n-hexane extract, which was stirred and centrifuged. The n-hexane layer was discarded, and the methanol layer was evaporated to dryness. The residue was incubated with an antiserum mixture containing DHEA-7α- 3 H, pepsin-treated human immune serum globulin and bovine serum albumin. Ammonium sulfate was used to separate free from bound DHEA-7α- 3 H. The accuracy, precision, sensitivity, and specificity were satisfactory. Good agreement was found between the serum DHEA levels obtained by the present radioimmunoassay and those obtained by radioimmunoassay with paper chromatography, making this method suitable for routine use. (U.S.)

Determination of mangiferin solubility in solvents used in the biopharmaceutical industry

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Jhoany Acosta

2016-04-01

Full Text Available Context: Pharmacological properties and studies of methods of extraction of mangiferin have been reported, but there are not studies related to the solubility of mangiferin in the solvents used in the pharmaceutical industry. Aims: Study the solubility of mangiferin in different solvents used in the pharmaceutical industry. Methods: The mangiferin used had a purity of 97.3% determined by High-Performance Liquid Chromatographic (HPLC, and solubility measurements were made in ethanol, methanol, water, acetone, diethyl ether, and hexane at 5, 15, 30, 40, 50 and 600C of temperature. The mangiferin concentrations were determined by ultraviolet spectrometry at 254 nm. The experimental solubility data were correlated with the Van´t Hoff equation and the dissolution heat determined. Results: The solubility of mangiferin in pure solvents decreases with increasing of temperature and in the following order: ethanol>methanol>water>diethyl ether>acetone>n hexane. Conclusions: This results indicated that mangiferin is slightly soluble in ethanol, sparingly soluble in methanol and water and practically insoluble in diethyl ether, acetone, and n-hexane.

Mixed-Penetrant Sorption in Ultra-Thin Films of Polymer of Intrinsic Microporosity PIM-1

KAUST Repository

Ogieglo, Wojciech

2017-10-12

Mixed penetrant sorption into ultra-thin films of a super-glassy polymer of intrinsic microporosity (PIM-1) was studied for the first time by using interference-enhanced in-situ spectroscopic ellipsometry. PIM-1 swelling and the concurrent changes in its refractive index were determined in ultra-thin (12 - 14 nm) films exposed to pure and mixed penetrants. The penetrants included water, n-hexane and ethanol and were chosen based on their significantly different penetrant-penetrant and penetrant-polymer affinities. This allowed studying microporous polymer responses at diverse ternary compositions and revealed effects such as competition for the sorption sites (for water / n-hexane or ethanol / n-hexane) or enhancement in sorption of typically weakly sorbing water in the presence of more highly sorbing ethanol. The results reveal details of the mutual sorption effects which often complicate comprehension of glassy polymers\\' behavior in applications such as high-performance membranes, adsorbents or catalysts. Mixed-penetrant effects are typically very challenging to study directly and their understanding is necessary owing to a broadly recognized inadequacy of simple extrapolations from measurements in pure component environment.

Antibacterial activity of Valeriana jatamansi against extended-spectrum β-lactamase producing Gramnegative bacteria causing urinary tract infections

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Babar Habib

2016-10-01

Full Text Available Objective: To find out the antibacterial activity of Valeriana jatamansi (V. jatamansi rhizomes against the extended-spectrum β-lactamases (ESBLs producing isolates of Enterobacteriaceae family. Methods: Confirmation of ESBLs producing Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae and Hafnia alvei isolated from urinary tract infections was performed by double disc diffusion assay. Antimicrobial susceptibility of all ESBLs producing isolates was determined by disc diffusion method following guidelines of Clinical and Laboratory Standards Institute. Successive extraction of rhizomes of V. jatamansi was performed with hexane, chloroform and methanol using Soxhelt apparatus. These extracts were tested against the ESBLs producing isolates using well diffusion method. Results: Hexane extract showed significant results as compared to chloroform and methanol extracts with the maximum zone of inhibition (21 mm while ciprofloxacin and amikacin were used as standard drugs. Conclusions: Findings of the study suggested that hexane extract of V. jatamansi can be used in combination with other antibiotics as alternative treatment for urinary tract infections caused by ESBLs producing strains of Enterobacteriaceae.

Mixed-Penetrant Sorption in Ultrathin Films of Polymer of Intrinsic Microporosity PIM-1.

Science.gov (United States)

Ogieglo, Wojciech; Furchner, Andreas; Ghanem, Bader; Ma, Xiaohua; Pinnau, Ingo; Wessling, Matthias

2017-11-02

Mixed-penetrant sorption into ultrathin films of a superglassy polymer of intrinsic microporosity (PIM-1) was studied for the first time by using interference-enhanced in situ spectroscopic ellipsometry. PIM-1 swelling and the concurrent changes in its refractive index were determined in ultrathin (12-14 nm) films exposed to pure and mixed penetrants. The penetrants included water, n-hexane, and ethanol and were chosen on the basis of their significantly different penetrant-penetrant and penetrant-polymer affinities. This allowed studying microporous polymer responses at diverse ternary compositions and revealed effects such as competition for the sorption sites (for water/n-hexane or ethanol/n-hexane) or enhancement in sorption of typically weakly sorbing water in the presence of more highly sorbing ethanol. The results reveal details of the mutual sorption effects which often complicate comprehension of glassy polymers' behavior in applications such as high-performance membranes, adsorbents, or catalysts. Mixed-penetrant effects are typically very challenging to study directly, and their understanding is necessary owing to a broadly recognized inadequacy of simple extrapolations from measurements in a pure component environment.

Isolasi dan Identifikasi Senyawa Metabolit Sekunder Ekstrak n-Heksan dari Umbi Lobak (Raphanus Sativus Lamk

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Ummi Zahra

2013-01-01

Full Text Available Isolation and identification of secondary metabolite compound in extract of n-Hexane in Umbi Lobak (Raphanus sativus Lamk have been carried out. The purpose of this research is to know secondary metabolite compound which is contained in Umbi Lobak (Raphanus sativus Lamk which obtained from Gowa. The compound was obtained by isolation process that consists of several steps including extraction, fractination, purification, and identification. Extraction was carried out using maceration with n- hexane. The identification has done by phytochemistry test, melting point, solubility, TLC, and IR spectroscopy. The result of research found out that the obtained compound was the steroid compound, with melt point 133-133,5 oC and had positive  reaction toward Lieberman Burchad reagents, where the Lieberman Burchad reagent resulting is green which perfectly solved in n-hexane, bit solved in methanol, and could not be solved in aceton. TLC analysis showed a stain in three scales different solvent and the result of elucidation structure in IR spectrophotometer showed that compound which get is β sitosterol.

Solvent Extraction and Characterization of Neutral Lipids in Oocystis sp.

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Renil eAnthony

2015-01-01

Full Text Available Microalgae are a favorable feedstock for bioproducts and biofuels due to their high oil content, fast growth rates and low resource demands. Solvent lipid extraction efficiency from microalgae is dependent on algal strain and the extraction solvent. Four non-polar extraction solvents were evaluated for the recovery of neutral cellular lipids from microalgae Oocystis sp. (UTEX LB2396. Methylene chloride, hexane, diethyl ether, and cyclohexane were selected as the extraction solvents. All solvent extracts contained hexadecanoic acid, linoleic acid and linolenic acid; accounting for 70% of total lipid content with a proportional wt% composition of the three fatty acids, except for the hexane extracts that showed only hexadecanoic acid and linoleic acid. While not statistically differentiated, methylene chloride proved to be the most effective solvent for Oocystis sp. among the four solvents tested with a total average neutral lipid recovery of 0.25% of dry weight followed by diethyl ether (0.18%, cyclohexane (0.14% and hexane (0.11%. This research presents a simple methodology to optimize the selection of lipid specific extraction solvents for the microalgal strain selected.

FRACTIONATION OF FATTY ACID OMEGA 3, 6 AND 9 FROM SNAIL (Achatina fulica USING COLOUM CHROMATOGRAPHY

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Winarto Haryadi

2010-06-01

Full Text Available The extraction of fat from snail has been carried out by Soxhlet extractor with petroleum ether solvent. Fatty product from extraction was transesterificated in BF3/methanol solvent for an hour by reflux procedure, then extracted by n-hexane to produce methyl ester fatty acid. Free water fatty acid methyl ester was analyzed by Gas Chromatography-Mass spectrometer (GC-MS. Fatty acid ester was separated from its fractions use column chromatography in n-hexane, n-hexane:dietil eter (2:1 v/v, dietil eter, aseton, ethanol and methanol. This fractions wer also analized by GC-MS. From GC-MS data sheet can be obtained 5 fractions which details are; fraction 1 contains omega 3: 27.54 %, omega 6: 15.40 % and omega 9: 6.77 %. Fraction 2 contains omega 3: 3.08 %, omega 6: 15.62 % and omega 9: 10.72 %. Fraction 3 contains omega 6: 3.57 %, omega 9: 7.02 % and none omega 3 inside it. Omega 3, 6 and 9 can't be identification in fraction 4 and 5.   Keywords: extraction, transesterification, column chromatography, GC-MS

Large-scale solvent-swelling-based amplification of microstructured sharkskin

International Nuclear Information System (INIS)

Pan, Junfeng; Chen, Huawei; Zhang, Deyuan; Zhang, Xin; Yuan, Liming; Aobo, Li

2013-01-01

Sophisticated biomimetic microstructures/nanostructures have attracted attention worldwide, but their fabrication technique significantly restricts their application. This study uses natural sharkskin to investigate amplification (i.e., the bioscaling forming process) and thus acquire a complex microstructure that cannot be fabricated by traditional micromachining techniques. The bioscaling forming process adjusts the optimal function region of natural surfaces by utilizing the solvent-swelling effect of polydimethylsiloxane. To accurately replicate amplified sharkskin, the swelling ratio and rate in gaseous and liquid n-hexane were investigated. Epoxy resin was used to produce a positive sharkskin mold. A comparison between the microstructure of the original and amplified sharkskin shows that the swelling ratio can reach a maximum of 34% with gaseous n-hexane and 39% with liquid n-hexane. The accuracy of bioscaling forming was higher than 95%. The drag-reducing effect was also tested. When the sharkskin was amplified 1.34 times, the optimal velocity range of the drag reduction moved from 5.0 to 3.5 m s −1 . (paper)

Supercritical extraction of oleaginous: parametric sensitivity analysis

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Santos M.M.

2000-01-01

Full Text Available The economy has become universal and competitive, thus the industries of vegetable oil extraction must advance in the sense of minimising production costs and, at the same time, generating products that obey more rigorous patterns of quality, including solutions that do not damage the environment. The conventional oilseed processing uses hexane as solvent. However, this solvent is toxic and highly flammable. Thus the search of substitutes for hexane in oleaginous extraction process has increased in the last years. The supercritical carbon dioxide is a potential substitute for hexane, but it is necessary more detailed studies to understand the phenomena taking place in such process. Thus, in this work a diffusive model for semi-continuous (batch for the solids and continuous for the solvent isothermal and isobaric extraction process using supercritical carbon dioxide is presented and submitted to a parametric sensitivity analysis by means of a factorial design in two levels. The model parameters were disturbed and their main effects analysed, so that it is possible to propose strategies for high performance operation.

Effect of solvents and oil content on direct transesterification of wet oil-bearing microalgal biomass of Chlorella vulgaris ESP-31 for biodiesel synthesis using immobilized lipase as the biocatalyst.

Science.gov (United States)

Tran, Dang-Thuan; Chen, Ching-Lung; Chang, Jo-Shu

2013-05-01

In this work, a one-step extraction/transesterification process was developed to directly convert wet oil-bearing microalgal biomass of Chlorella vulgaris ESP-31 into biodiesel using immobilized Burkholderia lipase as the catalyst. The microalgal biomass (water content of 86-91%; oil content 14-63%) was pre-treated by sonication to disrupt the cell walls and then directly mixed with methanol and solvent to carry out the enzymatic transesterification. Addition of a sufficient amount of solvent (hexane is most preferable) is required for the direct transesterification of wet microalgal biomass, as a hexane-to-methanol mass ratio of 1.65 was found optimal for the biodiesel conversion. The amount of methanol and hexane required for the direct transesterification process was also found to correlate with the lipid content of the microalga. The biodiesel synthesis process was more efficient and economic when the lipid content of the microalgal biomass was higher. Therefore, using high-lipid-content microalgae as feedstock appears to be desirable. Copyright © 2012 Elsevier Ltd. All rights reserved.

Transient effects caused by pulsed gas and liquid injections into low pressure plasmas

International Nuclear Information System (INIS)

Ogawa, D; Goeckner, M; Overzet, L; Chung, C W

2010-01-01

The fast injection of liquid droplets into a glow discharge causes significant time variations in the pressure, the chemical composition of the gas and the phases present (liquid and/or solid along with gas). While the variations can be large and important, very few studies, especially kinetic studies, have been published. In this paper we examine the changes brought about in argon plasma by injecting Ar (gas), N 2 (gas) hexane (gas) and hexane (liquid droplets). The changes in the RF capacitively coupled power (forward and reflected), electron and ion density (n e , n i ), electron temperature (T e ) and optical emissions were monitored during the injections. It was found that the Ar injection (pressure change only) caused expected variations. The electron temperature reduced, the plasma density increased and the optical emission intensity remained nearly constant. The N 2 and hexane gas injections (chemical composition and pressure changes) also followed expected trends. The plasma densities increased and electron temperature decreased while the optical emissions changed from argon to the injected gas. These all serve to highlight the fact that the injection of evaporating hexane droplets in the plasma caused very little change. This is because the number of injected droplets is too small to noticeably affect the plasma, even though the shift in the chemical composition of the gas caused by evaporation from those same droplets can be very significant. The net conclusion is that using liquid droplets to inject precursors for low pressure plasmas is both feasible and controllable.

Screening of marine algae (Padina sp. from the Lengeh Port, Persian Gulf for antibacterial and antifungal activities

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Azadeh Taherpour

2016-09-01

Full Text Available Objective: To evaluate the antibacterial efficacy of different solvent extracts of Padina sp. against selected human pathogenic bacteria and fungi species such as Escherichia coli, Shigella sp., Staphylococcus aureus (S. aureus, Pseudomonas aeruginosa, Aspergillus flavus and Candida albicans. Methods: Various solvents including methanol, ethyl acetate, chloroform and hexane were used to acquire crude extracts from marine algae Padina sp. After crude preparation, antibacterial and antifungal activities were screened against clinically important human pathogenic bacteria using disc and well diffusion methods. For all the bacterial species used in this research, minimum inhibitory concentration was undertaken considering various solvent extracts of Padina sp. To ensure the accuracy of experiments, a positive control was also included. Results: Confirmed that hexane is the best solvent to extract antimicrobial agents from Padina sp. Among selected bacteria, S. aureus was the most sensitive test microorganism. While, all other microorganisms showed resistance against methanol, ethyl acetate, chloroform extracts. In fact, by increasing concentration of hexane extract, inhibition of S. aureus growth or antimicrobial activity was increased. Growth inhibition zone in well method showed better results compared to disc diffusion method. The minimum inhibitory concentration and minimum bactericidal concentration of hexane extract were 15 and 30 mg/mL against S. aureus, respectively. All Padina sp. extracts did not reveal any antifungal activities against fungi species in this study. Conclusions: Brown algae extracts showed sufficient antibacterial properties against S. aureus. Therefore, Padina sp. in this research can be a good candidate to design and manufacture novel antibacterial agents used in pharmaceutical industries.

Screening of Six Medicinal Plant Extracts Obtained by Two Conventional Methods and Supercritical CO₂ Extraction Targeted on Coumarin Content, 2,2-Diphenyl-1-picrylhydrazyl Radical Scavenging Capacity and Total Phenols Content.

Science.gov (United States)

Molnar, Maja; Jerković, Igor; Suknović, Dragica; Bilić Rajs, Blanka; Aladić, Krunoslav; Šubarić, Drago; Jokić, Stela

2017-02-24

Six medicinal plants Helichrysum italicum (Roth) G. Don, Angelica archangelica L., Lavandula officinalis L., Salvia officinalis L., Melilotus officinalis L., and Ruta graveolens L. were used. The aim of the study was to compare their extracts obtained by Soxhlet (hexane) extraction, maceration with ethanol (EtOH), and supercritical CO₂ extraction (SC-CO₂) targeted on coumarin content (by high performance liquid chromatography with ultraviolet detection, HPLC-UV), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging capacity, and total phenols (TPs) content (by Folin-Ciocalteu assay). The highest extraction yields were obtained by EtOH, followed by hexane and SC-CO₂. The highest coumarin content (316.37 mg/100 g) was found in M. officinalis EtOH extracts, but its SC-CO₂ extraction yield was very low for further investigation. Coumarin was also found in SC-CO₂ extracts of S. officinalis , R. graveolens , A. archangelica , and L. officinalis . EtOH extracts of all plants exhibited the highest DPPH scavenging capacity. SC-CO₂ extracts exhibited antiradical capacity similar to hexane extracts, while S. officinalis SC-CO₂ extracts were the most potent (95.7%). EtOH extracts contained the most TPs (up to 132.1 mg gallic acid equivalents (GAE)/g from H. italicum ) in comparison to hexane or SC-CO₂ extracts. TPs content was highly correlated to the DPPH scavenging capacity of the extracts. The results indicate that for comprehensive screening of different medicinal plants, various extraction techniques should be used in order to get a better insight into their components content or antiradical capacity.

Impurities that cause difficulty in stripping actinides from commercial tetraalkylcarbamoylmethylphosphonates

International Nuclear Information System (INIS)

Bahner, C.T.; Shoun, R.R.; McDowell, W.J.

1977-09-01

Dihexyl[(diethylcarbamoyl)methyl]phosphonate (DHDECMP) in diethylbenzene extracts actinides well from 6 M nitric acid solution, but commercially available DHDECMP contains impurities which interfere with stripping the actinides from the organic extract. DHDECMP purified by molecular distillation does not contain these impurities, but the pot residue contains increased concentrations of them. Heating the purified DHDECMP causes the formation of products which interfere with stripping in the same way, suggesting that high temperatures employed in the manufacture of DHDECMP may produce the offending impurities. These impurities can be separated from the heat-decomposed material or the pot residues by dilution with a large volume of hexanes (causing part of the impurities to separate as a second liquid phase) followed by equilibration of the hexane solution with dilute alkali. After the treatment with hexane and dilute alkali, the DHDECMP is readily recovered and functions well in the actinide extraction process. Dibutyl[(dibutylcarbamoyl)methyl]-phosphonate (DBDBCMP) and di(2-ethylhexyl)[(diethylcarbamoyl)-methyl]phosphonate (DEHDECMP) are purified less effectively by these methods. Similar separation methods using diethylbenzene or CCl 4 as solvent do not remove impurities as completely as the hexane process. Impurities can also be removed from a benzene solution of the DHDECMP pot residue by passing it through a column packed with silica gel or diethylaminoethyl cellulose. These impurities have been separated into fractions for analytical examination by use of various solvents and by column chromatography. Hexyl hydrogen [(diethylcarbamoyl)methyl]-phosphonate has been identified tentatively as a principal objectionable impurity. Dihexyl phosphoric acid and possibly dihexylphosphonate have been identified in other fractions

In vitro total phenolics, flavonoids contents and antioxidant activity of essential oil, various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.

Science.gov (United States)

Hossain, M Amzad; Shah, Muhammad Dawood; Gnanaraj, Charles; Iqbal, Muhammad

2011-09-01

To detect the in vitro total phenolics, flavonoids contents and antioxidant activity of essential oil, various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah. The dry powder leaves of Tetrastigma were extracted with different organic solvent such as hexane, ethyl acetate, chloroform, butanol and aqueous methanol. The total phenolic and total flavonoids contents of the essential oil and various organic extracts such as hexane, ethyl acetate, chloroform, butanol and aqueous ethanol were determined by Folin - Ciocalteu method and the assayed antioxidant activity was determined in vitro models such as antioxidant capacity by radical scavenging activity using α, α-diphenyl- β-picrylhydrazyl (DPPH) method. The total phenolic contents of the essential oil and different extracts as gallic acid equivalents were found to be highest in methanol extract (386.22 mg/g) followed by ethyl acetate (190.89 mg/g), chloroform (175.89 mg/g), hexane (173.44 mg/g), and butanol extract (131.72 mg/g) and the phenolic contents not detected in essential oil. The antioxidant capacity of the essential oil and different extracts as ascorbic acid standard was in the order of methanol extract > ethyl acetate extract >chloroform> butanol > hexane extract also the antioxidant activity was not detected in essential oil. The findings show that the extent of antioxidant activity of the essential oil and all extracts are in accordance with the amount of phenolics present in that extract. Leaves of Tetrastigma being rich in phenolics may provide a good source of antioxidant. Copyright © 2011 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Screening of Six Medicinal Plant Extracts Obtained by Two Conventional Methods and Supercritical CO2 Extraction Targeted on Coumarin Content, 2,2-Diphenyl-1-picrylhydrazyl Radical Scavenging Capacity and Total Phenols Content

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Maja Molnar

2017-02-01

Full Text Available Six medicinal plants Helichrysum italicum (Roth G. Don, Angelica archangelica L., Lavandula officinalis L., Salvia officinalis L., Melilotus officinalis L., and Ruta graveolens L. were used. The aim of the study was to compare their extracts obtained by Soxhlet (hexane extraction, maceration with ethanol (EtOH, and supercritical CO2 extraction (SC-CO2 targeted on coumarin content (by high performance liquid chromatography with ultraviolet detection, HPLC-UV, 2,2-diphenyl-1-picrylhydrazyl radical (DPPH scavenging capacity, and total phenols (TPs content (by Folin–Ciocalteu assay. The highest extraction yields were obtained by EtOH, followed by hexane and SC-CO2. The highest coumarin content (316.37 mg/100 g was found in M. officinalis EtOH extracts, but its SC-CO2 extraction yield was very low for further investigation. Coumarin was also found in SC-CO2 extracts of S. officinalis, R. graveolens, A. archangelica, and L. officinalis. EtOH extracts of all plants exhibited the highest DPPH scavenging capacity. SC-CO2 extracts exhibited antiradical capacity similar to hexane extracts, while S. officinalis SC-CO2 extracts were the most potent (95.7%. EtOH extracts contained the most TPs (up to 132.1 mg gallic acid equivalents (GAE/g from H. italicum in comparison to hexane or SC-CO2 extracts. TPs content was highly correlated to the DPPH scavenging capacity of the extracts. The results indicate that for comprehensive screening of different medicinal plants, various extraction techniques should be used in order to get a better insight into their components content or antiradical capacity.

Adsorption kinetics of alkanethiol-capped gold nanoparticles at the hexane–water interface

International Nuclear Information System (INIS)

Ferdous, Sultana; Ioannidis, Marios A.; Henneke, Dale

2011-01-01

The pendant drop technique was used to characterize the adsorption behavior of n-dodecane-1-thiol and n-hexane-1-thiol-capped gold nanoparticles at the hexane–water interface. The adsorption process was studied by analyzing the dynamic interfacial tension versus nanoparticle concentration, both at early times and at later stages (i.e., immediately after the interface between the fluids is made and once equilibrium has been established). A series of gold colloids were made using nanoparticles ranging in size from 1.60 to 2.85 nm dissolved in hexane for the interfacial tension analysis. Following free diffusion of nanoparticles from the bulk hexane phase, adsorption leads to ordering and rearrangement of the nanoparticles at the interface and formation of a dense monolayer. With increasing interfacial coverage, the diffusion-controlled adsorption for the nanoparticles at the interface was found to change to an interaction-controlled assembly and the presence of an adsorption barrier was experimentally verified. At the same bulk concentration, different sizes of n-dodecane-1-thiol nanoparticles showed different absorption behavior at the interface, in agreement with the findings of Kutuzov et al. (Phys Chem Chem Phys 9:6351–6358, 2007). The experiments additionally demonstrated the important role played by the capping agent. At the same concentration, gold nanoparticles stabilized by n-hexane-1-thiol exhibited greater surface activity than gold nanoparticles of the same size stabilized by n-dodecane-1-thiol. These findings contribute to the design of useful supra-colloidal structures by the self-assembly of alkane-thiol-capped gold nanoparticles at liquid–liquid interfaces.

Antimicrobial activity of Ulva reticulata and its endophytes

Science.gov (United States)

Dhanya, K. I.; Swati, V. I.; Vanka, Kanth Swaroop; Osborne, W. J.

2016-04-01

Seaweeds are known to exhibit various antimicrobial properties, since it harbours an enormous range of indigenous bioactive compounds. The emergence of drug resistant strains has directed to the identification of prospective metabolites from seaweed and its endophytes, thereby exploiting the properties in resisting bacterial diseases. The current study was aimed to assess the antimicrobial activity of extracts obtained from Ulva reticulate, for which metabolites of Ulva reticulata and its endophytes were extracted and assessed against human pathogens like Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, and Bacillus subtilis. It was observed that the hexane extract of isolate VITDSJ2 was effective against all the tested pathogens but a significant inhibition was observed for Staphylococcus aureus and Escherichia coli. Further, Gas chromatography coupled with Mass spectroscopy (GC-MS) revealed the existence of phenol, 3, 5-bis (1, 1-dimethylethyl) in the crude hexane extract which is well-known to possess antibacterial activity. The effective isolate VITDSJ2 was identified to be the closest neighbour of Pseudomonas stutzeri by phenotypic and genotypic methods. The crude extracts of the seaweed Ulva reticulata was also screened for antibacterial activity and the hexane extract was effective in showing inhibition against all the tested pathogens. The compound in the crude extract of Ulva reticulata was identified as hentriacontane using GC-MS. The extracts obtained from dichloromethane did not show significant activity in comparison with the hexane extracts. Hence the metabolites of Ulva reticulata and the bacterial secondary metabolites of the endophytes could be used in the treatment of bacterial infections.

Evaluation of antimicrobial and anti-inflammatory activities of seed extracts from six Nigella species.

Science.gov (United States)

Landa, Premysl; Marsik, Petr; Havlik, Jaroslav; Kloucek, Pavel; Vanek, Tomas; Kokoska, Ladislav

2009-04-01

Seed extracts from six species of the genus Nigella (Family Ranunculaceae)-Nigella arvensis, Nigella damascena, Nigella hispanica, Nigella nigellastrum, Nigella orientalis, and Nigella sativa-obtained by successive extraction with n-hexane, chloroform, and methanol, were tested for their antimicrobial activity against 10 strains of pathogenic bacteria and yeast using the microdilution method as well as for anti-inflammatory properties by in vitro cyclooxygenase (COX)-1 and COX-2 assay. Chemical characterization of active extracts was carried out including free and fixed fatty acid analysis. Comparison of antimicrobial activity showed that N. arvensis chloroform extract was the most potent among all species tested, inhibiting Gram-positive bacterial and yeast strains with minimum inhibitory concentration (MIC) values ranging from 0.25 to 1 mg/mL. With the exception of selective inhibitory action of n-hexane extract of N. orientalis on growth of Bacteroides fragilis (MIC = 0.5 mg/mL), we observed no antimicrobial activity for other Nigella species. Anti-inflammatory screening revealed that N. sativa, N. orientalis, N. hispanica, N. arvensis n-hexane, and N. hispanica chloroform extracts had strong inhibitory activity (more than 80%) on COX-1 and N. orientalis, N. arvensis, and N. hispanica n-hexane extracts were most effective against COX-2, when the concentration of extracts was 100 microg/mL in both COX assays. In conclusion, N. arvensis, N. orientalis, and N. hispanica seeds, for the first time examined for antimicrobial and anti-inflammatory effects, revealed their significant activity in one or both assays.

Determination of alpha-Tocopherol (vitamin E) in irradiated garlic by high performance liquid chromatography (HPLC); Determinacao de alpha-tocoferol em alho irradiado utilizando cromatografia liquida de alta frequencia (CLAE)

Energy Technology Data Exchange (ETDEWEB)

Rios, Magda Dias Goncalves; Penteado, Marilene de Vuono Camargo [Sao Paulo Univ., SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Alimentos e Nutricao Experimental]. E-mail: riosmagda@hotmail.com

2003-02-01

The effects of {sup 60}Co ionizing radiations in doses of 0, 75, 100, 150, 200 and 250Gy on garlic, upon the {alpha}-tocopherol concentration were studied. The {alpha}-tocopherol contents were established by high performance liquid chromatography (HPLC), after direct hexane extraction from the garlic samples. The {alpha}-tocopherol was determined through normal phase column, and mobile phase was composed by hexane: iso-propyl alcohol (99:01 v/v), with 2mL/min flow rate and fluorescence detector. It is statistically shown that an irradiation dose of up to 150 Gy does not affect the garlic {alpha}-tocopherol content. (author)

Porosity and liquid absorption of cement paste

DEFF Research Database (Denmark)

Krus, M.; Hansen, Kurt Kielsgaard; Kunzel, H. M.

1997-01-01

be a slowing-down effect which is related to water because the absorption of organic liquids, such as hexane, is quite normal. Measurements of the porosity of hardened cement paste determined by helium pycnometry and water saturation show that water molecules can enter spaces in the microstructure which...... are not accessible to the smaller helium atoms. Considering the results of dilatation tests both before and after water and hexane saturation, it seems possible that a contraction of capillary pores due to moisture-related swelling of the cement gel leads to the non-linear water absorption over the square root...

Coefficients of interphase distribution and Gibbs energy of the transfer of nicotinic acid from water into aqueous solutions of ethanol and dimethylsulfoxide

Science.gov (United States)

Grazhdan, K. V.; Gamov, G. A.; Dushina, S. V.; Sharnin, V. A.

2012-11-01

Coefficients of the interphase distribution of nicotinic acid are determined in aqueous solution systems of ethanol-hexane and DMSO-hexane at 25.0 ± 0.1°C. They are used to calculate the Gibbs energy of the transfer of nicotinic acid from water into aqueous solutions of ethanol and dimethylsulfoxide. The Gibbs energy values for the transfer of the molecular and zwitterionic forms of nicotinic acid are obtained by means of UV spectroscopy. The diametrically opposite effect of the composition of binary solvents on the transfer of the molecular and zwitterionic forms of nicotinic acid is noted.

Determination of alpha-Tocopherol (vitamin E) in irradiated garlic by high performance liquid chromatography (HPLC)

International Nuclear Information System (INIS)

Rios, Magda Dias Goncalves; Penteado, Marilene de Vuono Camargo

2003-01-01

The effects of 60 Co ionizing radiations in doses of 0, 75, 100, 150, 200 and 250Gy on garlic, upon the α-tocopherol concentration were studied. The α-tocopherol contents were established by high performance liquid chromatography (HPLC), after direct hexane extraction from the garlic samples. The α-tocopherol was determined through normal phase column, and mobile phase was composed by hexane: iso-propyl alcohol (99:01 v/v), with 2mL/min flow rate and fluorescence detector. It is statistically shown that an irradiation dose of up to 150 Gy does not affect the garlic α-tocopherol content. (author)

Hydration of ammonia, methylamine, and methanol in amorphous solid water

Science.gov (United States)

Souda, Ryutaro

2016-02-01

Interactions of polar protic molecules with amorphous solid water (ASW) have been investigated using temperature-programmed desorption and time-of-flight secondary ion mass spectrometry. The ammonia and methylamine are incorporated into the interior of porous ASW films. They are caged by water molecules and are released during water crystallization. In contrast, the methanol-water interaction is not influenced by pores of ASW. The methanol additives tend to survive water crystallization and are released during ASW film evaporation. The hydration of n-hexane in ASW is influenced significantly by methanol additives because n-hexane is accommodated in a methanol-induced hydration shell.

Isolation And Purification Of Flavonoids From The Leaves Of Locally Produced Carica Papaya

Directory of Open Access Journals (Sweden)

Yahaya Mobmi Musa

2015-08-01

Full Text Available ABSTRACT The leaves of Carica papaya 150g was defatted with N-Hexane and extracted with Methanol. The N-Hexane exract showed the presence of Flavonoid Saponin Tannin Glycoside Anthraquinone Resin and Steroid while Methanolic extract showed the presence of Flavonoid Saponin and Resins. 6g of the Methanolic extract was chromatographed using Column chromatography over Silica gel of column 200g60-200 mesh and eluted with the solvent mixture of CH2Cl2CH3OH H2O in the ratio of 70301. The yield of the isolated Flavonoid was 0.23.

Hexanic fraction of turmeric powder attenuates murine model of ...

African Journals Online (AJOL)

... of any detectable toxicity and sedative effects exerts pronounced peripheral and central antinociceptive effects, with no involvement of opioidergic system but possibly related to its ability to interact with TRPV1 receptors and the glutamatergic system. Keywords: Curcuma longa L., Antinociceptive, TRPV1, Glutamatergic ...

Gastroprotective Activities of the n-Hexane Fraction of Heliotropium ...

African Journals Online (AJOL)

) to evaluate the histo- gastroprotective effects of H. indicum on Indomethacin – induced gastric ulcerated mucosa of wistar rats. None of the rats used in this study died while the experimental procedures lasted. Thus, all rats were histologically.

Cytotoxic Activity of Hexane Extracts of Psidium guajava L ...

African Journals Online (AJOL)

, kaempferol, which was identified as a constituent of the extract. Conclusion: The results suggest that further chemical analysis and mechanistic investigations should be conducted on P. guajava and C. alata extracts to validate their potential ...

Cytotoxic Activity of Hexane Extracts of Psidium Guajava L ...

African Journals Online (AJOL)

HP

, kaempferol, which was identified as a constituent of the extract. Conclusion: The results suggest that further chemical analysis and mechanistic investigations should be conducted on P. guajava and C. alata extracts to validate their potential ...

Hexane extract of Dacryodes edulis fruits possesses anti-diabetic ...

African Journals Online (AJOL)

Background: The fruit extract of Dacryodes edulis (D. edulis), the African pear or plum, a tree indigenous to the humid tropics has been used for managing wounds, skin diseases, sickle cell anaemia, dysentery and fever in some African nations. In South Eastern Nigeria, 'herbal doctors' include its marshed fruit in decoctions ...

Tetracarbonylbis(η5-cyclopentadienylbis(diphenylphosphinedimolybdenum(Mo—Mo hexane solvate

Directory of Open Access Journals (Sweden)

David R. Tyler

2008-07-01

Full Text Available The title compound, [Mo2(C5H52(C12H11P2(CO4]·C6H14, is a centrosymmetric Mo complex in which two Mo atoms are connected by an Mo—Mo bond [3.2072 (12 Å]. Each Mo atom is coordinated by an η5-cyclopentadienyl ligand, two carbonyl ligands and a diphenylphosphine ligand in a piano-stool fashion.

Effect Of Chronic Administration Of Hexane Extract Of Byrsonima ...

African Journals Online (AJOL)

Background: In Mexican traditional medicine, the seeds of Byrsonima crassifolia have been used in the treatment of diabetes, rheumatism and for wound healing. The aim was to evaluate the effect of seeds of B. crassifolia on insulin release from the pancreatic beta cells in streptozotocininduced diabetic rats. Materials and ...

Anti-venom Potentials of Friedelin Isolated from Hexane Extract

African Journals Online (AJOL)

USER

474. Selvanayagam et al.,1995). Quite a good record of plant anti-venom agents used among the various ethnic groups and regions of Nigeria has been established through ethnobanical and ethnomedical records. Notably ...... Guidelines for the Management of snake-bites. WHO Library Cataloguing-in-. Publication data ...

Haematological and biochemical evaluation of the n -hexane extract ...

African Journals Online (AJOL)

The study undertook to evaluate the sub-chronic toxicological profile of the seed of Ricinus communis var. minor (RICOM-1013-J), widely used as anticonceptive agent among Bassa people of Plateau State, Nigeria, on haematological and biochemical parameters in adult rats. Thirty-six (36) adult female rats were divided ...

The Study of Compound Quality of various Siam Weed (Eupatorium odoratum) Extracts and Toxicity Detoxification mechanisms Against 3rd Instar Larvae of Fruit Fly (Dacus dorsalis)

International Nuclear Information System (INIS)

Sutthivaiyakit, Pakawadee; Visetson, Suraphon; Sutthivaiyakit, Somyote; Patharakorn, Thipamon; Patharakorn, Surapol; Piadang, Patharakorn

2006-09-01

The 1H-NMR spectroscopy showed signals of DeltaH tild0.71.6 from hexane-leaf extracts from Siam weed (Eupatorium odoratum) These signals derive from protons of non-polar compounds which include fatty acid residues and terpinoids. In addition, the amplification of the signals indicated of some minor DeltaH tild6.2-7.7. This revealed protons from aromatic rings possibly involving in flavonoids from 1H-NMR spectrum. This is a believe that is a believe that these compounds could be varied from slightly polar compounds to moderately polar compounds. Furthermore, the Thin Layer Chromatography (TLC) of hexane, chloroform and methanol fractions showed the extracts composed of majority of less polar. It is and indication of the method of separation is quite food for separation of polarity basis from these extracts. Finally, the TLC of hexane fraction distinctively produced 7-8 compounds from the extracts. Toxicity testing using topical spray method showed that methnoloc extracts gave highest toxicity against 3rd instar larvae of fruit fly (Darcus dorsalis). The root extracts produced ca. 5 fold mohile GSH-S-transferase ws elevated 2-3 fold. The addition of dimethyl maleate into the extraccts increased their toxicity. The persistent experiment of eupathal from the extracts showed that the extracts can be stabilixed under aqueous solution upto 1 month with losing the compound. Finally, the Siam weed extracts prosuced non toxic to non-target organisms such as gabbies, bee, and mouse. The results of LC50 showed 15,000-26,000 mg/L 6,000-15,000 mg/L and 3,000-10,000 mg/L from hexane, chloroform and methanol extracts, respectively.

Antinociceptive and antipyretic activities of extracts and fractions from Dracaena loureiri in experimental animals

Directory of Open Access Journals (Sweden)

Pisit Bouking

2003-07-01

Full Text Available Dried coarsely powdered material from the stem woods of Dracaena loureiri Gagnep (D loureiri has extracted with hexane and methanol to give hexane and methanol extracts, respectively. The methanol extract was roughly separated into four fractions. They were methanol, methanol + water, chloroform and ethyl acetate fractions. The effects of the methanol extract, hexane extract, methanol fraction, methanol + water fraction, ethyl acetate fraction and chloroform fraction on nociceptive response using writhing, hot plate and formalin tests in mice and the antipyretic activity in yeast-induced fever in rats, were examined. General behavior was also examined using pentobarbital-induced sleep in mice. The LD5 0 value of intraperitoneally injected the methanol extract, hexane extract, methanol fraction, ethyl acetate fraction and chloroform fraction in mice was 1.67 g/kg, >7 g/kg, 739.73 mg/kg, 489.77 mg/kg and 1.67 g/kg, respectively. Oral administration of the methanol extract and methanol fraction of D. loureiri (100-400 mg/kg dose de- pendently decreased the number of writhings and stretchings induced by acetic acid and licking activity of the late phase in the formalin test. All extracts or fractions of D. loureiri had no effects on heat-induced pain in mice. Only the methanol fraction of D. loureiri suppressed yeast-induced fever in rats. Neither extracts nor fractions affected paw edema induced by carrageenin in rats. The methanol extract of D. loureiri (100- 400 mg/kg, p.o. prolonged the duration of pentobarbital-induced sleep in mice. These results suggest that the methanol extract and the methanol fraction of D. loureiri possess analgesic effect. Only the methanol fraction of the extract exhibited antipyretic effect.

Natural Occurrence of Aldol Condensation Products in Valencia Orange Oil.

Science.gov (United States)

Abreu, Ingo; Da Costa, Neil C; van Es, Alfred; Kim, Jung-A; Parasar, Uma; Poulsen, Mauricio L

2017-12-01

Cold pressed orange oils contain predominantly d-limonene (approximately 95%) and various other lower concentration monoterpenes, sesquiterpenes, sinensals plus 3 key aliphatic aldehydes: hexanal, octanal. and decanal. The aldol self-condensation products or "dimers" for each aldehyde have been postulated as being present at low concentrations in the oil. However, to date only the hexanal dimer has been previously reported. In this paper, cold pressed Valencia orange oil was fractionally distilled/folded and analyzed by GC and high resolution GC-MS to detect these compounds on 2 different capillary column phases. Subsequently the hexanal, octanal, and decanal self-aldol condensation products, 2-butyl-2-octenal, 2-hexyl-2-decenal, and 2-octyl-2-dodecenal, respectively, were detected in the folded oil. These predominantly trans configuration isomeric compounds were synthesized, to confirm them as being present in nature and evaluated organoleptically by a panel of evaluators. To further confirm the mechanism of their formation, the enriched oil was made into a simple beverage to show the effect on the formation of these aldol compounds under acidic conditions. Finally aliphatic aldehydes from hexanal to undecanal were reacted together in various combinatorial pairs to give an additional 33 self and mixed aldol condensation products, some of which were also detected in the folded oil. This paper discloses the structural elucidation and synthesis of 8 novel aldol condensation products found at trace concentrations in citrus and leading to a further 31 mass spectrally determined aldol products. Sensory evaluations and application of some of these components were demonstrated in a model citrus beverage. © 2017 Institute of Food Technologists®.

A comparison of geochemical features of extracts from coal-seams source rocks with different polarity solvents

Energy Technology Data Exchange (ETDEWEB)

Chen, Jianping; Deng, Chunping; Wang, Huitong

2009-02-15

There exists a great difference in group-type fractions and biomarker distributions of chloroform extracts from coals and coal-seams oils, which makes the source identification of coal-seams oils in sedimentary basins rather difficult. The experiment, in which four different polarity solvents, n-hexane, benzene, dichloromethane and chloroform, were used to extract 9 coal-seams source rocks and 3 typical lacustrine source rocks, showed that the yield of extracts increased gradually with increasing solvent polarity. The distribution features of their n-alkanes, isoprenoids and sterane and terpane biomarkers remained, in general, similar, showing no distinct enrichment or depletion for a certain fraction by any solvent. The compositional analysis on n-hexane and chloroform extracts showed that the absolute amount (concentration) of biomarkers was relatively low for the n-hexane extract but comparatively high for the chloroform extract, this difference became great among coal-seams source rocks but small among lacustrine mudstones. The statistical analysis on the relative amount of the 18 major biomarkers in n-hexane and chloroform extracts from 10 source rock samples showed that extracts with a proportional error for the same biomarker of less than 5% (including the analytical error) accounted for 84% while those with a proportional error over 10% amounted to below 5%. This suggested that the outcome of oil-source correlation made by these biomarkers will be independent of variations in amounts of saturates and biomarkers arising from solvent polarity. Therefore, biomarkers obtained from organic-rich source rocks including coals by the extraction with the commonly used chloroform solvent can be applied for the oilsource correlation of coal-seams petroliferous basins.

Evaluation of the Hypoglycaemic Activity of Petiveria alliacea (Guinea Hen Weed) Extracts in Normoglycaemic and Diabetic Rat Models.

Science.gov (United States)

Christie, S-L; Levy, A

2013-11-01

Petiveria alliacea (P alliacea) has ethno-traditional use as a hypoglycaemic agent in Jamaica and is yet to be scientifically validated as such. Therefore, extracts of aerial parts of the plant were evaluated for hypoglycaemic activity in normoglycaemic and diabetic rats. Aqueous and hexane extracts prepared from leaves of P alliacea were tested for hypoglycaemic activity. An acute administration of the extracts (200 and 400 mg/kg body weight) was evaluated in normoglycaemic rats. Additionally, the hypoglycaemic effect of sub-chronic administration was assessed in streptozotocin-induced diabetic rats. Blood glucose was recorded using a glucometer and test strips. Data were analysed using Student's t-test (p ≤ 0.05). The aqueous and hexane extracts demonstrated no significant reduction of fasting blood glucose (FBG) and no significant improvement of glucose tolerance in normal rats. The aqueous extract (400 mg/kg body weight) increased FBG from 4.75 ± 0.28 mmol/L to 5.88 ± 0.46 when compared to control (p ≤ 0.001). In diabetic rats, the hexane extract (400 mg/kg body weight) caused reduction of FBG after two weeks of treatment (p ≤ 0.010), but this was not sustained. The aqueous extract showed no reduction of FBG in diabetic rats. The aqueous extract of P alliacea demonstrated a hyperglycaemic effect in normoglycaemic rats and showed no hypoglycaemic activity in diabetic rats. The hexane extract caused no hypoglycaemic action in normal rats and failed to sustain an initial hypoglycaemic action in diabetic rats. This study presents evidence that does not support significant hypoglycaemic activity of P alliacea; this could hold significant implications for its use in ethno-traditional medicine.

Study of the Performance of the Organic Extracts of Chenopodium ambrosioides for Ag Nanoparticle Synthesis

Directory of Open Access Journals (Sweden)

Luis M. Carrillo-López

2016-01-01

Full Text Available There are many ways to obtain metal nanoparticles: biological, physical, and chemical ways and combinations of these approaches. Synthesis assisted with plant extracts has been widely documented. However, one issue that is under discussion refers to the metabolites responsible for reduction and stabilization that confine nanoparticle growth and prevent coalescence between nanoparticles in order to avoid agglomeration/precipitation. In this study, Ag nanoparticles were synthesized using organic extracts of Chenopodium ambrosioides with different polarities (hexane, dichloromethane, and methanol. Each extract was phytochemically characterized to identify the nature of the metabolites responsible for nanoparticle formation. With methanol extract, the compounds responsible for reducing and stabilizing silver nanoparticle were associated with the presence of phenolic compounds (flavonoids and tannins, while, with dichloromethane and hexane extracts, the responsible compounds were mainly terpenoids. Large part of the reducing activity of secondary metabolites in C. ambrosioides is closely related to compounds with antioxidant capacity, such as phenolic compounds (flavone glycoside and isorhamnetin, which are the main constituents of the methanol extracts. Otherwise, terpenoids (trans-diol, α-terpineol, monoterpene hydroperoxides, and apiole are the central metabolites present in dichloromethane and hexane extracts.

Composite Ag/C:H:N films prepared by planar magnetron deposition

Energy Technology Data Exchange (ETDEWEB)

Hlidek, P. [Charles University, Faculty of Mathematics and Physics, Praha (Czech Republic)], E-mail: hlidek@karlov.mff.cuni.cz; Hanus, J.; Biederman, H.; Slavinska, D.; Pesicka, J. [Charles University, Faculty of Mathematics and Physics, Praha (Czech Republic)

2008-05-30

Composite Ag/C:H:N films were deposited by means of an unbalanced magnetron operated in a gas mixture of nitrogen and n-hexane. Composition of the films was controlled by electric power delivered to the magnetron and by ratio of nitrogen and n-hexane in the working gas mixture. The films were characterized using transmission electron microscopy, by the absorption spectra in visible and near infrared regions and by Fourier transform infrared spectroscopy. Immediately after film deposition and without breaking vacuum (in situ) corresponding vibration infrared spectra were scanned and their evolution during ageing of the films was monitored. Wettability as determined from water contact angle was improved with raising nitrogen contents, i.e. with increasing the electric power and the ratio of nitrogen/n-hexane in the working gas mixture. The increased wettability is likely caused by presence of NH{sub x} groups in Ag/C:H:N films. The incorporation of nitrogen effectively prevents the formation of carboxylate groups on the silver inclusions surfaces during the aging in the open air. In addition, the oxidation mechanism of the polymer matrix is modified.

Magnitude of [14C] DDT residues in stored dried fish and pre-cooking processing effect on their removal

International Nuclear Information System (INIS)

Rahman, M.; Khatoon, J.; Matin, M.A.; Main, A.J.

1998-01-01

Residues of 14 C-DDT in stored dried fish was determined under ambient conditions for a 6 month period. Immediately after treatment, about 40% of the applied DDT was eliminated from surface of the dried fish with water washing. However, such removal was reduced to about 26% on storage for 6 months. Boiling of dried fish in water resulted in further removal of about 16% residues. In boiled dried fish, about 14% residues might remain and this could be removed by Soxhlet extraction. Surface extraction with hexane yielded about 80% of the residues immediately after treatment and the extractable residues decreased to about half the initial value of 6 months' storage. Dried fish residues, on surface extraction with water or hexane, when subjected to exhaustive Soxhlet extraction with methanol was found to result in further recovery of about 39-49% and 17-32%, respectively. Bound DDT residues were found to be about 5% in water washed dried fish samples and about 1.5% in case of hexane-extracted samples. Degradation of parent DDT to DDE and DDD was found. Maximum values of 16.58% DDE and 21.6% DDD were found in dried fish stored for 6 months. (author)

Evaluation of in-vitro antibacterial activity and anti-inflammatory activity for different extracts of Rauvolfia tetraphylla L. root bark.

Science.gov (United States)

Ganga Rao, B; Umamaheswara Rao, P; Sambasiva Rao, E; Mallikarjuna Rao, T; Praneeth D, V S

2012-10-01

To assess the in-vitro antibacterial activity and anti-inflammatory activity of orally administered different extracts (Hydro-alcoholic, methanolic, ethyl acetate and hexane) of Rauvolfia tetraphylla (R. tetraphylla) root bark in Carrageenan induced acute inflammation in rats. In-vitro antibacterial activity was evaluated for extracts against four Gram positive and four Gram negative bacteria by using cylinder plate assay. Hydro-alcoholic extract (70% v/v ethanol) at 200, 400 and 800 mg/kg doses and methanolic, ethyl acetate and hexane extracts at doses 100, 200 and 400 mg/kg were tested for anti-inflammatory activity in Carrageenan induced rat paw oedema model and paw thickness was measured every one hour up to 6 hrs. All extracts of R. tetraphylla root bark showed good zone of inhibition against tested bacterial strains. In Carrageenan induced inflammation model, hydro-alcoholic and methanolic extract of R. tetraphylla root bark at three different doses produced significant (P<0.001) reduction when compared to vehicle treated control group and hexane, ethyl acetate extracts. In the present study extracts of R. tetraphylla root bark shows good in-vitro antibacterial activity and in-vivo anti-inflammatory activity in rats.

ANTIPROLIFERATIVE EFFECT ON BREAST CANCER (MCF7) OF MORINGA OLEIFERA SEED EXTRACTS.

Science.gov (United States)

Adebayo, Ismail Abiola; Arsad, Hasni; Samian, Mohd Razip

2017-01-01

Moringa oleifera belongs to plant family, Moringaceae and popularly called "wonderful tree", for it is used traditionally to cure many diseases including cancer in Africa and Asia, however, there is limited knowledge on cytotoxic activity of Moringa oleifera seeds on MCF7 breast cancer cell. The present study evaluated antiproliferative effect on MCF7 of the seed. Seeds of Moringa oleifera were grinded to powder and its phytochemicals were extracted using water and 80% ethanol solvents, part of the ethanolic extract were sequentially partitioned to fractions with four solvents (hexane, dichloromethane, chloroform, and n-butanol). Antiproliferative effects on MCF7 of the samples were determined. Finally, potent samples that significantly inhibited MCF7 growth were tested on MCF 10A. Crude water extract, hexane and dichloromethane fractions of the seeds inhibited the proliferation of MCF7 with the following IC 50 values 280 μg/ml, 130 μg/ml and 26 μg/ml respectively, however, of the 3 samples, only hexane fraction had minimal cytotoxic effect on MCF 10A (IC 50 > 400μg/ml). Moringa oleifera seed has antiproliferative effect on MCF7.

Solvent Extraction and Characterization of Neutral Lipids in Oocystis sp

Energy Technology Data Exchange (ETDEWEB)

Anthony, Renil [Department of Mechanical Engineering, Ohio University, Athens, OH (United States); Stuart, Ben, E-mail: stuart@ohio.edu [Department of Civil Engineering, Ohio University, Athens, OH (United States)

2015-01-20

Microalgae are a favorable feedstock for bioproducts and biofuels due to their high oil content, fast growth rates, and low resource demands. Solvent lipid extraction efficiency from microalgae is dependent on algal strain and the extraction solvent. Four non-polar extraction solvents were evaluated for the recovery of neutral cellular lipids from microalgae Oocystis sp. (University of Texas at Austin LB2396). Methylene chloride, hexane, diethyl ether, and cyclohexane were selected as the extraction solvents. The lipid extracts were derivatized and analyzed using gas chromatography–mass spectroscopy. All solvent extracts contained hexadecanoic acid, linoleic acid, and linolenic acid; accounting for 70% of total lipid content with a proportional wt% composition of the three fatty acids, except for the hexane extracts that showed only hexadecanoic acid and linoleic acid. While not statistically differentiated, methylene chloride proved to be the most effective solvent for Oocystis sp. among the four solvents tested with a total average neutral lipid recovery of 0.25% of dry weight followed by diethyl ether (0.18%), cyclohexane (0.14%), and hexane (0.11%). This research presents a simple methodology to optimize the selection of lipid specific extraction solvents for the microalgal strain selected.

Evaluation of the chiral recognition properties and the column performances of three chiral stationary phases based on cellulose for the enantioseparation of six dihydropyridines by high-performance liquid chromatography.

Science.gov (United States)

Yu, Jia; Tang, Jing; Yuan, Xiaowei; Guo, Xingjie; Zhao, Longshan

2017-03-01

Separations of six dihydropyridine enantiomers on three commercially available cellulose-based chiral stationary phases (Chiralcel OD-RH, Chiralpak IB, and Chiralpak IC) were evaluated with high-performance liquid chromatography (HPLC). The best enantioseparation of the six chiral drugs was obtained with a Chiralpak IC (250 × 4.6 mm i.d., 5 μm) column. Then the influence of the mobile phase including an alcohol-modifying agent and alkaline additive on the enantioseparation were investigated and optimized. The optimal mobile phase conditions and maximum resolution for every analyte were as follows respectively: n-hexane/isopropanol (85:15, v/v) for nimodipine (R = 5.80) and cinildilpine (R = 5.65); n-hexane/isopropanol (92:8, v/v) for nicardipine (R = 1.76) and nisoldipine (R = 1.92); and n-hexane/isopropanol/ethanol (97:2:1, v/v/v) for felodipine (R = 1.84) and lercanidipine (R = 1.47). Relative separation mechanisms are discussed based on the separation results, and indicate that the achiral parts in the analytes' structure showed an important influence on the separation of the chiral column. © 2017 Wiley Periodicals, Inc.

Curcuma aeruginosa, a novel botanically derived 5α-reductase inhibitor in the treatment of male-pattern baldness: a multicenter, randomized, double-blind, placebo-controlled study.

Science.gov (United States)

Pumthong, Ganniga; Asawanonda, Pravit; Varothai, Supenya; Jariyasethavong, Vorapicha; Triwongwaranat, Daranporn; Suthipinittharm, Puan; Ingkaninan, Kornkanok; Leelapornpisit, Pimporn; Waranuch, Neti

2012-10-01

Several botanically derived agents are available for the treatment of male-pattern baldness. The aim of this study was to evaluate the efficacy of 5% hexane extract of Curcuma aeruginosa, a botanically derived inhibitor of 5α-reductase and 5% minoxidil in the treatment of androgenetic alopecia. Eighty-seven men with androgenetic alopecia (AGA) were randomized to receive 5% Curcuma aeruginosa, 5% minoxidil, combination formulation (5% hexane extract of Curcuma aeruginosa + 5% minoxidil) or placebo, twice daily for 6 months. Efficacy was assessed by target area hair count, global photographic review as well as patients' subjective assessments of hair regrowth and hair shedding. There were statistically significant improvements in global photographic review (p < 0.001), subjects' overall assessments of hair regrowth (p = 0.008), and hair shedding (p = 0.004) when the combination formulation was compared with placebo. Similarly, treatment with 5% minoxidil and 5% C. aeruginosa extract also led to some degrees of hair regrowth. There were no serious adverse events during and after the study. In men with hair loss in the vertex area of the scalp, the combination of 5% hexane extract of C. aeruginosa and 5% minoxidil slowed hair loss and increased hair growth.

UJI TOKSISITAS (Brine Shrimp Lethality Test DAN AKTIVITAS ANTIOKSIDAN DARI DAUN SINTRONG (Crassocephalum Crepidioides DENGAN METODE 2,2-diphenyl-1-picrylhidrazil (DPPH

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Fiktor Boni Pasilala

2016-11-01

Full Text Available The phytochemical test, brine shrimp lethality test and antioxidant activity test on secondary metabolits of terap (Artocarpus odoratissimus B. leaves has been completed. The leaves samples are extracted by masseration method that is concentrated by using rotary evaporator. The total extract are fractioned with n-hexane and ethyl acetate. Based on secondary metabolits phytochemical test of terap (Artocarpus odoratissimus B. leaves showed that total extract and Ethyl Acetat fraction extract contains alkaloids, phenolics, flavonoids, saponins, steroids and triterpenoids. N-hexane fraction extract contain alkaloids, steroids and tritepenoids. In brine shrimp lethality test, the increase larvae death data was recorded and processed using SAS Probit Analysis to determine the Lethal Concentration 50 % (LC50 value. The results of this test showed that the most active extract is metanol extract with LC50 value of 88.0227 ppm. Based on the antioxidant activity by scavenging activity of DPPH used spectrophotometry was obtained that Inhibition Concentration 50% (IC50 of total extract is 369.0833 ppm, extract of n-hexane fraction is 1532.267 ppm and extract of ethyl acetat fraction is 82.89003 ppm.

Antiulcerogenic activity of crude extract, fractions and populnoic acid isolated from Austroplenckia populnea (Celastraceae).

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Andrade, Sérgio F; Antoniolli, Daiane; Comunello, Eros; Cardoso, Luis G V; Carvalho, José C T; Bastos, Jairo K

2006-01-01

Many plant crude extracts and their isolated compounds are the most attractive sources of new drugs and show promising results for the treatment of gastric ulcers. Austroplenckia populnea is commonly known as "marmelinho-do campo, mangabeira-brava, mangabarana and vime" and it has been used in folk medicine as anti-dysenteric and anti-rheumatic. Powdered bark wood (3.25 kg) was macerated with aqueous ethanol (96%) and the extract was concentrated under reduced pressure to yield 406 g of crude hydralcoholic extract. The hydralcoholic extract was suspended in aqueous methanol and partitioned with hexane, chloroform and ethyl acetate (EtOAc) in sequence, yielding 8.0 g, 9.5 g and 98.17 g of crude extracts, respectively. Chromatography of the hexane extract over a silica gel column led to the isolation of the triterpene populnoic acid. The oral administration of hydralcoholic, hexane, chloroform and EtOAc extracts (200 mg/kg) decreased the ulcer lesion index (ULI) by 83.15%, 46.87%, 32.2%, 68.12%, respectively. Oral administration of populnoic acid (100 mg/kg) diminished the ULI by 55.29%. All the obtained results were significant in comparison with the negative control, with exception of the chloroform extract.

Intermedin A, a New Labdane Diterpene Isolated from Alpinia intermedia, Prolonged the Survival Time of P-388D1 Tumor-Bearing CDF1 Mice.

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Chen, Lih-Geeng; Su, Pei-Jung; Tsai, Po-Wei; Yang, Ling-Ling; Wang, Ching-Chiung

2017-01-01

Eight ethanolic extracts of indigenous Taiwanese plants of the genus Alpinia were tested for tumor cytotoxicity against AGS, Hep G2, HeLa, KB, and HL-60 cells. Among the 50 % and 95 % EtOH extracts of eight Alpinia species, the cytotoxic effects of Alpinia intermedia leaves were the strongest. When the leaf extract of A. intermedia was partitioned using n -hexane and aqueous solvents, the n -hexane layer showed a greater cytotoxic effect and could prolong the survival time of P-388D 1 tumor-bearing CDF1 mice. Two new labdane diterpene derivatives, intermedin A ( 1 ) and intermedin B ( 2 ), and coronarin E ( 3 ) were isolated from the n -hexane layer of A. intermedia . Intermedin A induced apoptosis in HL-60 cells at 30 µg/mL and significantly prolonged the survival time of P-388D 1 tumor-bearing CDF 1 mice by 48.7 % at 20 mg/kg of body weight. We suggest that intermedin A is a major compound of A. intermedia and has a cytotoxic effect on HL-60 and P-388D 1 cells. Georg Thieme Verlag KG Stuttgart · New York.

Insecticidal, food utilisation and biochemical effect of essential oils extracted from seeds of Brassica juncea (Czern. against Spodoptera litura (Lepidoptera: Noctuidae (Fabricius

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Shallina Gupta

2017-09-01

Full Text Available The glucosinolate rich hot and cold hexane extracts of Brassica juncea had a negative effect on the development of Spodoptera litura larvae when they were fed on different concentrations of the extracts. Both larval growth index and pupal growth index declined with treatment. However the hot extract with 3-butenyl isothiocyanate as the predominant compound had a more deleterious effect as at 3125ppm the larvae were unable to complete their development. The nutritional indices too were more adversely affected with hot extract as compared to cold extract. The RGR, RCR, ECI and ECD declined significantly with increase in concentration of the hot hexane extract. The activity of antioxidant enzymes, SOD and catalase decreased while that of phosphatases, GSTs, phenol oxidases increased during the initial treatment duration but decreased on prolonged treatment of the larvae with LC50 concentration of hot extract. A similar trend was observed for glutathione and lipid peroxides but a decrease in ascorbate content was observed as compared to control. The findings reveal a toxic effect of 3-butenylisothiocyanate rich hot hexane extract of B. juncea on S. litura larvae.

Solvent Extraction and Characterization of Neutral Lipids in Oocystis sp

International Nuclear Information System (INIS)

Anthony, Renil; Stuart, Ben

2015-01-01

Microalgae are a favorable feedstock for bioproducts and biofuels due to their high oil content, fast growth rates, and low resource demands. Solvent lipid extraction efficiency from microalgae is dependent on algal strain and the extraction solvent. Four non-polar extraction solvents were evaluated for the recovery of neutral cellular lipids from microalgae Oocystis sp. (University of Texas at Austin LB2396). Methylene chloride, hexane, diethyl ether, and cyclohexane were selected as the extraction solvents. The lipid extracts were derivatized and analyzed using gas chromatography–mass spectroscopy. All solvent extracts contained hexadecanoic acid, linoleic acid, and linolenic acid; accounting for 70% of total lipid content with a proportional wt% composition of the three fatty acids, except for the hexane extracts that showed only hexadecanoic acid and linoleic acid. While not statistically differentiated, methylene chloride proved to be the most effective solvent for Oocystis sp. among the four solvents tested with a total average neutral lipid recovery of 0.25% of dry weight followed by diethyl ether (0.18%), cyclohexane (0.14%), and hexane (0.11%). This research presents a simple methodology to optimize the selection of lipid specific extraction solvents for the microalgal strain selected.

The Phenolic Compound from Kalanchoe blossfeldiana (Crassulaceae Leaf and Its Antiplasmodial Activity against Plasmodium falciparum 3D7

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Yenny Febriani Yun

2016-08-01

Full Text Available Various species of Kalanchoe plants have been widely used as raw materials in traditional medicines. This study was the continuation of the researches on secondary metabolites from Indonesia Kalanchoe plants, focused on Kalanchoe blossfeldiana. Fresh K. blossfeldiana leaf was extracted with methanol at room temperature to obtain the concentrated extract. The concentrated methanol extract was dissolved in water and then partitioned successively with n-hexane and ethyl acetate. The methanol, n-hexane, ethyl acetate extracts were tested using antiplasmodial assay against Plasmodium falciparum 3D7. The IC50 of methanol, n-hexane, and ethyl acetate extract were 13.002; 2.807, and 11 nM, respectively. Ethyl acetate extract was separated by the combination of chromatography on silica and ODS. This process produced the yellow solid. The chemical structure of the compound was determined based on UV, IR, MS, 1H-NMR, and 13C-NMR analyses and the comparison of data obtained from the literature and identified as phenolic compound, namely 3,3',4',5,7-pentahydroxyflavone or quercetin (1, and displayed antiplasmodial activity with IC50 3.97x10-2 nM.

Antioxidant and antimicrobial activity of stingless bee bread and propolis extracts

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Akhir, Rabieatul Adawieah Md; Bakar, Mohd Fadzelly Abu; Sanusi, Shuaibu Babaji

2017-10-01

Bee bread and propolis are by-products of honey bee. The main objective of this research was to investigate the antioxidant and antimicrobial activity of stingless bee bread and propolis extracted using 70% ethanol and n-hexane. The antioxidant activity of the sample extracts were determined by spectrophotometry analysis while for the antimicrobial activity, the sample extracts were analyzed using disc diffusion and broth dilution assays. For DPPH and ABTS assays, the results showed that ethanolic extract of bee bread showed the highest free radical scavenging (%) as compared to other samples. However, FRAP values for both hexanic extracts are higher as compared to the ethanolic extracts. For disc diffusion assay, the results showed that the ethanolic extract of bee bread and propolis as well as hexanic extract of propolis were able to inhibit all tested bacteria. Meanwhile, broth dilution assay showed minimum inhibition zone (MIC) ranging from <6.67 to 33.33 µL/mL. As the conclusion, both bee bread and propolis produced by stingless bee in this study displayed antioxidant and antimicrobial effect but there are different in the degree of antioxidant and antimicrobial activity exhibited between each of the samples.

Antiamoebic Activity of Petiveria alliacea Leaves and Their Main Component, Isoarborinol.

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Zavala Ocampo, Lizeth M; Aguirre-HernÁndez, Eva; Pérez-HernÁndez, Nury; Rivera, Gildardo; Marchat, Laurence A; Ramírez-Moreno, Esther

2017-08-28

Petiveria alliacea L. (Phytolacaceae) is a medicinal plant with a broad range of traditional therapeutic properties, including the treatment of dysentery and intestinal infections caused by protozoan parasites. However, its effects against Entamoeba histolytica have not been reported yet. We investigated the antiamoebic activity present in the leaves of P. alliacea Antiamoebic activity was evaluated in methanolic and aqueous extracts, as well as in the hexanic, methanolic, and EtOAc fractions. The P. alliacea methanolic extract showed a better antiamoebic activity than the aqueous extract with an IC 50 = 0.51 mg/ml. Likewise, the hexanic fraction was the most effective fraction, showing a dose-dependent activity against E. histolytica , with an IC 50 = 0.68 mg/ml. Hexanic subfraction 12-19 showed the highest antiamoebic activity at 0.8 mg/ml, producing 74.3% growth inhibition without any toxicity in mammal cells. A major component in subfraction 12-19 was identified as isoarborinol, which produced 51.4% E. histolytica growth inhibition at 0.05 mg/ml without affecting mammal cells. The P. alliacea leaf extract has antiamoebic activity that can be attributed to a major metabolite known as isoarborinol.

Thermodynamics of coproportionation reactions of homogeneous samarium (3) and yttrium (3) nitrates solvates with neutral organic phosphorus compounds

International Nuclear Information System (INIS)

Pyartman, A.K.

1995-01-01

Reaction heats of homogeneous samarium (3) and yttrium (3) nitrate solvates coproportionation with neutral organophosphoric compounds (tri-n.-butylphosphate, diisooctylmethylphosphonate, diisoamylmethylphosphonate) at T=298.15 K in hexane have been measured by thermochemical method. It has been ascertained that enthalpies of coproportionation reactions practically do not depend on the nature, concentration of rare earth metal (3) nitrate solvates in hexane, nature of neutral organophosphoric compound and constitute 1.1±-.2 kJ/mol. The Gibbs free energy of coproportionation reactions is -5.43 kJ/mol, while entropy of the reactions in 14.5±0.7 J/mol·K. 8 refs., 1 tab

Comparison of solvent extraction and solid-phase extraction for the determination of polychlorinated biphenyls in transformer oil.

Science.gov (United States)

Mahindrakar, A N; Chandra, S; Shinde, L P

2014-01-01

Solid-phase extraction (SPE) of nine polychlorinated biphenyls (PCBs) from transformer oil samples was evaluated using octadecyl (CI8)-bonded porous silica. The efficiency of SPE of these PCBs was compared with those obtained by solvent extraction with DMSO and hexane. Average recoveries exceeding 95% for these PCBs were obtained via the SPE method using small cartridges containing 100mg of 40 pm CI8-bonded porous silica. The average recovery by solvent extraction with DMSO and hexane exceeded 83%. It was concluded that the recoveries and precision for the solvent extraction of PCBs were poorer than those for the SPE. Copyright © 2013 Elsevier Ltd. All rights reserved.

Defatting and Sonication Enhances Protein Extraction from Edible Insects.

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Choi, Byoung Deug; Wong, Nathan A K; Auh, Joong-Hyuck

2017-01-01

Edible insects are attracting growing interest as a sustainable source of protein for addition to processed meat and dairy products. The current study investigated the optimal method for protein extraction from mealworm larvae ( Tenebrio molitor ), cricket adults ( Gryllus bimaculatus ), and silkworm pupae ( Bombyx mori ), for use in further applications. After defatting with n-hexane for up to 48 h, sonication was applied for 1-20 min and the protein yield was measured. All samples showed a total residual fat percentage below 1.36%, and a 35% to 94% improvement in protein yield (%). In conclusion, defatting with n-hexane combined with sonication improves the protein yield from insect samples.

Co-extraction of lactic acid by tri-n-octylamine and tri-n-butyl phosphate; Tori-n-okuchiruamin to tori-n-rinsanbuchiru niyoru nyusan no kyodochushutsu

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, Michiaki; Yuba, Seiji; Kondo, Kazui

1999-01-05

Co-extraction of lactic acid was examined as a fundamental research for establishing in situ extraction fermentation process of lactic acid (HA). Addition of tri-n-butyl phosphate (TBP) into an extraction system of lactic acid by tri-n-octylamine (TOA) using hexane as the dilutor brought about a great cooperative effect. The extracting reaction in this system is analyzed by taking into consideration the formation of HA-TOA-2TBP. Further, when a TBP and TOA-containing hexane solution was added into a culture system of a lactic acid bacteria Lactobacillus rhamnosus, latic acid of 65% in a system without addition of an organic solvent was produced. (translated by NEDO)

Application of solid state NMR for the study of surface bound species and fossil fuels

Energy Technology Data Exchange (ETDEWEB)

Althaus, Stacey [Iowa State Univ., Ames, IA (United States)

2014-01-01

In this study, stimulated echo with pulsed field gradients was used to measure the diffusion of two different solvents, water and hexane, in AP-MSN-2.7 and AP-MSN-3.7. The resulting data were then fit using two different methods. Based on these fits, the diffusion of hexane in AP-MSN-2.7 was shown to be slower than in the larger pores. This agrees well with our studies of catalytic activity, which show an increase in the reaction rate with the increase in pore size. Thus, both substrate inhibition and diffusion played a role in the decreased efficiency of the APMSN with small pore sizes.

Rotational Isomers, Intramolecular Hydrogen Bond, and IR Spectra of o-Vinylphenol Homologs

Science.gov (United States)

Glazunov, V. P.; Berdyshev, D. V.; Balaneva, N. N.; Radchenko, O. S.; Novikov, V. L.

2018-03-01

The ν(OH) stretching-mode bands in solution IR spectra of five o-vinylphenol (o-VPh) homologs in the slightly polar solvents CCl4 and n-hexane were studied. Several rotamers with free OH groups were found in solutions of o-VPh and its methyl-substituted derivatives in n-hexane. The proportion of rotamers in o-VPh homologs with intramolecular hydrogen bonds (IHBs) O-H...π varied from 22 to 97% in the gas and cyclohexane according to B3LYP/cc-pVTZ calculations. The theoretically estimated effective enthalpies -ΔH of their IHBs varied in the range 0.20-2.24 kcal/mol.

Efficacy and safety of a hexanic extract of Serenoa repens (Permixon® ) for the treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia (LUTS/BPH): Systematic review and meta-analysis of randomized controlled trials and observational studies.

Science.gov (United States)

Vela-Navarrete, Remigio; Alcaraz, Antonio; Rodríguez-Antolín, Alfredo; Miñana López, Bernardino; Fernández-Gómez, Jesús M; Angulo, Javier C; Castro Díaz, David; Romero-Otero, Javier; Brenes, Francisco J; Carballido, Joaquín; Molero García, José M; Fernández-Pro Ledesma, Antonio; Cózar Olmos, José Manuel; Manasanch Dalmau, José; Subirana Cachinero, Isaac; Herdman, Michael; Ficarra, Vincenzo

2018-04-25

To comprehensively evaluate the efficacy and safety of the hexanic extract of Serenoa repens (HESr, Permixon), at a dose of 320 mg daily, as monotherapy for the treatment of LUTS/BPH. Systematic review and meta-analysis of randomized and observational studies in patients with LUTS/BPH identified through searches in Medline, Web of Knowledge [ISI], Scopus, the Cochrane Library, and bibliographic references up to March 2017. Articles studying S. repens extracts other than Permixon were excluded. Data was collected on IPSS score, peak urinary flow (Qmax), nocturia, quality of life, prostate volume, sexual function, and adverse drug reactions (ADR). Data obtained from randomized controlled trials (RCT) and observational studies (OS) were analysed jointly and separately using a random effects model. A sub-group analysis was performed of studies which included patients on longer-term treatment (≥one year). Data from 27 studies (15 RCTs and 12 OS) were included for meta-analysis (total N=5,800). Compared with placebo, the HESr was associated with 0.64 (95% CI -0.98 to -0.31) fewer voids per night (p=0.0001) and an additional mean increase in Qmax of 2.75 mL/s (95% CI 0.57 to 4.93; p=0.01). When compared with alpha-blockers, the HESr showed similar improvements on IPSS (WMD 0.57; 95%CI, -0.27 to 1.42; p=0.18) and a comparable increase in Qmax to tamsulosin (WMD -0.02; 95%CI, -0.71 to 0.66; p=0.95). Efficacy assessed using the IPSS was similar after 6 months of treatment between the HESr and 5ARIs. Analysis of all available published data for the HESr showed a mean improvement in IPSS score from baseline of -5.73 points (95% CI -6.91 to -4.54; pBPH. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Chemical composition, antioxidant, antitumor, anticancer and cytotoxic effects of Psidium guajava leaf extracts.

Science.gov (United States)

Ashraf, Aisha; Sarfraz, Raja Adil; Rashid, Muhammad Abid; Mahmood, Adeel; Shahid, Muhammad; Noor, Nadia

2016-10-01

Context Psidium guajava L. (Myrtaceae) leaves are used in traditional medicines for the treatment of cancer, inflammation and other ailments. Objective The current study explores scientific validation for this traditional medication. Materials and methods We used ferric-reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picryl hydrazil (DPPH) assays to estimate antioxidant activity of P. guajava leaf extracts (methanol, hexane and chloroform). Antitumour and in vivo cytotoxic activities were determined using potato disc assay (PDA) and brine shrimp lethality assay, respectively. Three human carcinoma cell lines (KBM5, SCC4 and U266) were incubated with different doses (10-100 μg/mL) of extracts and the anticancer activity was estimated by MTT assay. NF-κB suppressing activity was determined using electrophoretic mobility shift assay (EMSA). Chemical composition of the three extracts was identified by GC-MS. Total phenolic and flavonoid contents were measured by colorimetric assays. Results and discussions The order of antioxidant activity of three extracts was methanol > chloroform > hexane. The IC50 values ranged from 22.73 to 51.65 μg/mL for KBM5; 22.82 to 70.25 μg/mL for SCC4 and 20.97 to 89.55 μg/mL for U266 cells. The hexane extract exhibited potent antitumour (IC50  value = 65.02 μg/mL) and cytotoxic (LC50  value = 32.18 μg/mL) activities. This extract also completely inhibited the TNF-α induced NF-κB activation in KBM5 cells. GC-MS results showed that pyrogallol, palmitic acid and vitamin E were the major components of methanol, chloroform and hexane extracts. We observed significant (p guajava leaf extracts play a substantial role against cancer and down-modulate inflammatory nuclear factor kB.

Improvements of insulin resistance in ovariectomized rats by a novel phytoestrogen from Curcuma comosa Roxb

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Prasannarong Mujalin

2012-03-01

Full Text Available Abstract Background Curcuma comosa Roxb. (C. comosa is an indigenous medicinal herb that has been used in Thailand as a dietary supplement to relieve postmenopausal symptoms. Recently, a novel phytoestrogen, (3R-1,7-diphenyl-(4E,6E-4,6-heptadien-3-ol or compound 049, has been isolated and no study thus far has investigated the role of C. comosa in preventing metabolic alterations occurring in estrogen-deprived state. The present study investigated the long-term effects (12 weeks of C. comosa hexane extract and compound 049 on insulin resistance in prolonged estrogen-deprived rats. Methods Female Sprague-Dawley rats were ovariectomized (OVX and treated with C. comosa hexane extract (125 mg, 250 mg, or 500 mg/kg body weight (BW and compound 049 (50 mg/kg BW intraperitoneally three times per week for 12 weeks. Body weight, food intake, visceral fat weight, uterine weight, serum lipid profile, glucose tolerance, insulin action on skeletal muscle glucose transport activity, and GLUT-4 protein expression were determined. Results Prolonged ovariectomy resulted in dyslipidemia, impaired glucose tolerance and insulin-stimulated skeletal muscle glucose transport, as compared to SHAM. Treatment with C. comosa hexane extract and compound 049, three times per week for 12 weeks, markedly reduced serum total cholesterol and low-density lipoprotein levels, improved insulin sensitivity and partially restored uterine weights in ovariectomized rats. In addition, compound 049 or high doses of C. comosa hexane extract enhanced insulin-mediated glucose uptake in skeletal muscle and increased muscle GLUT-4 protein levels. Conclusions Treatment with C. comosa and its diarylheptanoid derivative improved glucose and lipid metabolism in estrogen-deprived rats, supporting the traditional use of this natural phytoestrogen as a strategy for relieving insulin resistance and its related metabolic defects in postmenopausal women.

Effect of surface roughness and softness on water capillary adhesion in apolar media.

Science.gov (United States)

Banerjee, Soumi; Mulder, Pieter; Kleijn, J Mieke; Cohen Stuart, Martien A

2012-06-28

The roughness and softness of interacting surfaces are both important parameters affecting the capillary condensation of water in apolar media, yet are poorly understood at present. We studied the water capillary adhesion between a cellulose surface and a silica colloidal probe in hexane by AFM force measurements. Nanomechanical measurements show that the Young's modulus of the cellulose layer in water is significantly less (~7 MPa) than in hexane (~7 GPa). In addition, the cellulose surface in both water and hexane is rather rough (6-10 nm) and the silica probe has a comparable roughness. The adhesion force between cellulose and silica in water-saturated hexane shows a time-dependent increase up to a waiting time of 200 s and is much (2 orders of magnitude) lower than that expected for a capillary bridge spanning the whole silica probe surface. This suggests the formation of one or more smaller bridges between asperities on both surfaces, which is confirmed by a theoretical analysis. The overall growth rate of the condensate cannot be explained from diffusion mediated capillary condensation alone; thin film flow due to the presence of a wetting layer of water at both the surfaces seems to be the dominant contribution. The logarithmic time dependence of the force can also be explained from the model of the formation of multiple capillary bridges with a distribution of activation times. Finally, the force-distance curves upon retraction show oscillations. Capillary condensation between an atomically smooth mica surface and the silica particle show less significant oscillations and the adhesion force is independent of waiting time. The oscillations in the force-distance curves between cellulose and silica may stem from multiple bridge formation between the asperities present on both surfaces. The softness of the cellulose surface can bring in additional complexities during retraction of the silica particle, also resulting in oscillations in the force-distance curves.

Socioeconomic and personal behavioral factors affecting children's exposure to VOCs in urban areas in Korea.

Science.gov (United States)

Byun, Hyaejeong; Ryu, Kyongnam; Jang, Kyungjo; Bae, Hyunjoo; Kim, Dongjin; Shin, Hosung; Chu, Jangmin; Yoon, Chungsik

2010-02-01

Volatile organic compounds (VOCs) are known to cause adverse health effects. We investigated the relationships between children's VOC exposure and socioeconomic and human activity factors with passive personal samplers, questionnaires, and time-activity diaries (TAD). Statistical analyses were conducted using SAS 9.1, and the results were organized using SigmaPlot 8.0 software. Chemicals such as benzene, toluene, 2-butanone, ethylbenzene, xylene, chloroform, n-hexane, heptane, and some kinds of decanes, which are known to adversely affect public health, were identified in measured samples. These were mainly emitted from outdoor sources (e.g., vehicular traffic) or indoor sources (e.g., household activities such as cooking and cleaning) or both. We concluded that region was the most important socioeconomic factor affecting children's VOC exposure, and the significant compounds were n-hexane (p = 0.006), 1,1,1-trichloroethane (p = 0.001), benzene (p = 0.003), toluene (p = 0.002), ethylbenzene (p = 0.020), m-, p-xylene (p = 0.014), dodecane (p = 0.003), and hexadecane (p = 0.001). Parental education, year of home construction and type of housing were also slightly correlated with personal VOC exposure. Only the concentration of o-xylene (p = 0.027) was significantly affected by the parental education, and the concentrations of benzene (p = 0.030) and 2-butanone (p = 0.049) by the type of housing. Also, tridecane (p = 0.049) and n-hexane (p = 0.033) were significantly associated with the year of home construction. When household activities such as cooking were performed indoors, children's VOC concentrations tended to be higher, especially for n-hexane, chloroform, heptane, toluene (p factors simultaneously, socioeconomic factors such as region had a greater effect on children's VOC exposures than indoor activities. From this study, we can suggest that socioeconomic factors as well as environmental factors should be considered when formulating environmental policy to

In-vitro investigations of the speed of pyrrole formation of 2,5-hexanedione and 2,5-heptanedione with N{alpha}-acetyl-L-lysine as a precondition for a comparative assessment of the neurotoxic potentials of the two {gamma}-diketones; In-vitro-Untersuchungen zur Pyrrolbildungsgeschwindigkeit von 2,5-Hexandion und 2,5-Heptandion mit N{alpha}-Acetyl-L-lysin als Voraussetzung fuer eine vergleichende Abschaetzung der neurotoxischen Potentiale beider {gamma}-Diketone

Energy Technology Data Exchange (ETDEWEB)

Richter, M.F.

1997-09-01

N-hexane and n-heptane are important solvents. Chronic exposure to n-hexane causes polyneuropathies, which are attributed to the metabolite 2,5-hexanedione, a {gamma} diketone. As a basis for a comparative assessment of the neurotoxic potentials of 2,5-hexanedione and 2,5-heptanedione, an in-vitro test was developed and used to investigate the speed of pyrrole formation of the two {gamma} diketones in reacting with the {epsilon} amino group of N{alpha}-acetyl L-lysine. The speed of the formation of pyrrole was always directly proportional to the respective reactant concentration. It consequently is subject to a second-order kinetics. As a further result, the pyrrole formation speed of 2,5-heptanedione was found to be only half that of 2,5-hexanedione. The results lead to the conclusion that 2,5-heptanedione poses a smaller risk of developing peripheral neuropathy than 2,5-hexanedione. (orig./MG) [Deutsch] n-Hexan und n-Heptan sind wichtige Loesungsmittel. Chronische Exposition gegenueber n-Hexan ruft Polyneuropathien hervor, die auf den Metaboliten 2,5-Hexandion, ein {gamma}-Diketon, zurueckgefuehrt werden. Als Grundlage fuer eine vergleichende Abschaetzung der neurotoxischen Potentiale von 2,5-Hexandion und 2,5-Heptandion wurde in der vorliegenden Arbeit ein In-vitro-Test entwickelt, mit dem die Pyrrolbildungsgeschwindigkeiten der beiden {gamma}-Diketone mit der {epsilon}-Aminogruppe von N{alpha}-Acetyl-L-Iysin untersucht wurden. Die Pyrrolbildungsgeschwindigkeit war stets direkt proportional zur jeweiligen Reaktantenkonzentration. Somit unterliegt sie einer Kinetik 2. Ordnung. Weiterhin wurde gezeigt, dass die Pyrrolbildungsgeschwindigkeit fuer 2,5-Heptandion nur etwa halb so gross ist wie fuer 2,5-Hexandion. Aus den Ergebnissen wird gefolgert, dass das von 2,5-Heptandion ausgehende Risiko an peripheren Neuropathien zu erkranken geringer ist, als das von 2,5-Hexandion ausgehende. (orig./MG)

Evaluation of the larvicidal efficiency of stem, roots and leaves of the weed, Parthenium hysterophorus (Family: Asteraceae against Aedes aegypti L.

Directory of Open Access Journals (Sweden)

Sarita Kumar

2012-10-01

Full Text Available Objective: To assess the larvicidal potential of various extracts prepared from the stem, roots and leaves of Parthenium hysterophorus (P. hysterophorus against 3rd and 4th instars of Aedes aegypti (Ae. aegypti. Methods: The extracts from each part were prepared with four solvents; petroleum ether, hexane, acetone and diethyl ether. Each part was dried, powdered and soaked in different solvents, separately, for five days. The crude extracts thus formed were concentrated using rotary evaporator and stored as stock solution of 1 000 mg/L. Results: All the extracts prepared from the leaves were found ineffective against both the instars causing only 10%-40% mortality. Against 3rd instars, the hexane and petroleum ether extracts prepared from the stem of P. hysterophorus were found effective exhibiting LC50 values of 379.76 and 438.57 mg/L, respectively. Likewise the hexane and petroleum ether extracts from the Parthenium roots resulted in LC50 values of 432.38 and 562.50 mg/L, respectively, against 4th instars of Ae. aegypti revealing their larvicidal potential. It was further found that the hexane extracts, whether from roots or stem, were 13-28% more effective than the petroleum ether extracts. The qualitative phytochemical study of the effective extracts from the stems and roots showed the presence of alkaloids, saponins, terpenoids and flavonoids in different combinations. Conclusions: Our investigations demonstrated the potential of P. hysterophorus roots and stems against Ae. aegypti larvae and their benefits as new types of mosquito larvicides. Variety of types and levels of active constituents in each kind of extract may be responsible for the variability in their potential against Ae. aegypti. Further research is needed to identify these components.

Refining of fossil resin flotation concentrate from western coal. Final report

Energy Technology Data Exchange (ETDEWEB)

Jensen, G.F.; Miller, J.D.

1995-02-16

During the past several years, significant research efforts have been made to develop process technology for the selective flotation of fossil resin from western coals. As a result of these efforts, several new flotation technologies have been developed. Operation of a proof-of-concept continuous flotation circuit showed the selective flotation process to be sufficiently profitable to justify the development of a fossil resin industry. However, little attention has been given to the refining of the fossil resin flotation concentrate although solvent refining is a critical step for the fossil resin to become a marketable product. In view of this situation, DOE funded this two-year project to evaluate the following aspects of the fossil resin refining technology: 1) Characterization of the fossil resin flotation concentrate and its refined products; 2) Kinetics of fossil resin extraction; 3) Effects of operating variables on solvent extraction; 4) Extraction solvents; 5) Proof-of-concept continuous refining tests; and 6) Technical and economic analysis. The results from this research effort have led to the following conclusions: Hexane- or heptane-refined fossil resin has a light-yellow color, a melting point of 140 - 142{degrees}C, a density of 1.034 gram/cm, and good solubility in nonpolar solvents. Among the four solvents evaluated (hexane, heptane, toluene and ethyl acetate), hexane is the most appropriate solvent based on overall technical and economic considerations. Batch extraction tests and kinetic studies suggest that the main interaction between the resin and the solvent is expected to be the forces associated with solvation phenomena. Temperature has the most significant effect on extraction rate. With hexane as the solvent, a recovery of 90% cam be achieved at 50{degrees}C and 10% solids concentration with moderate agitation for 1 hour.

Two-State Intramolecular Charge Transfer (ICT) with 3,5-Dimethyl-4-(dimethylamino)benzonitrile (MMD) and Its Meta-Isomer mMMD. Ground State Amino Twist Not Essential for ICT.

Science.gov (United States)

Druzhinin, Sergey I; Galievsky, Victor A; Demeter, Attila; Kovalenko, Sergey A; Senyushkina, Tamara; Dubbaka, Srinivas R; Knochel, Paul; Mayer, Peter; Grosse, Christian; Stalke, Dietmar; Zachariasse, Klaas A

2015-12-10

From X-ray structure analysis, amino twist angles of 90.0° for 2,4-dimethyl-3-(dimethylamino)benzonitrile (mMMD), 82.7° for 4-(di-tert-butylamino)benzonitrile (DTABN), and 88.7° for 6-cyanobenzoquinuclidine (CBQ) are determined, all considerably larger than the 57.4° of 3,5-dimethyl-4-(dimethylamino)benzonitrile (MMD). This large twist leads to lengthening of the amino-phenyl bond, 143.5 pm (mMMD), 144.1 pm (DTABN), 144.6 pm (CBQ), and 141.4 pm (MMD), as compared with 136.5 pm for the planar 4-(dimethylamino)benzonitrile (DMABN). As a consequence, the electronic coupling between the amino and phenyl subgroups in mMMD, DTABN, CBQ, and MMD is much weaker than in DMABN, as seen from the strongly reduced molar absorption coefficients. The fluorescence spectrum of MMD in n-hexane at 25 °C consists of two emissions, from a locally excited (LE) and an intramolecular charge transfer (ICT) state, with a fluorescence quantum yield ratio Φ'(ICT)/Φ(LE) of 12.8. In MeCN, a single ICT emission is found. With mMMD in n-hexane, in contrast, only LE fluorescence is observed, whereas the spectrum in MeCN originates from the ICT state. These differences are also seen from the half-widths of the overall fluorescence bands, which in n-hexane are larger for MMD than for mMMD, decreasing with solvent polarity for MMD and increasing for mMMD, reflecting the disappearance of LE and the onset of ICT in the overall spectra, respectively. From solvatochromic measurements the dipole moments μe(ICT) of MMD (16 D) and mMMD (15 D) are obtained. Femtosecond excited state absorption (ESA) spectra at 22 °C, together with the dual (LE + ICT) fluorescence, reveal that MMD in n-hexane undergoes a reversible LE ⇄ ICT reaction, with LE as the precursor, with a forward rate constant ka = 5.6 × 10(12) s(-1) and a back-reaction kd ∼ 0.05 × 10(12) s(-1). With MMD in the strongly polar solvent MeCN, ICT is faster: ka = 10 × 10(12) s(-1). In the case of mMMD in n-hexane, the ESA spectra show

Antimicrobial, Anti-Inflammatory, Antiparasitic, and Cytotoxic Activities of Laennecia confusa

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María G. Martínez Ruiz

2012-01-01

Full Text Available The current paper investigated the potential benefit of the traditional Mexican medicinal plant Laennecia confusa (Cronquist G. L. Nesom (Asteraceae. Fractions from the hexane, chloroform, methanol, and aqueous extracts were analyzed for antibacterial, antifungal, anti-inflammatory, and antiparasitic activities. The antimicrobial activity of the extracts and fractions was assessed on bacterial and fungal strains, in addition to the protozoa Leishmania donovani, using a microdilution assay. The propensity of the plant's compounds to produce adverse effects on human health was also evaluated using propidium iodine to identify damage to human macrophages. The anti-inflammatory activity of the extracts and fractions was investigated by measuring the secretion of interleukin-6. Chemical analyses demonstrated the presence of flavonoids, cyanogenic and cardiotonic glycosides, saponins, sesquiterpene lactones, and triterpenes in the chloroform extract. A number of extracts and fractions show antibacterial activity. Of particular interest is antibacterial activity against Staphylococcus aureus and its relative methicillin-resistant strain, MRSA. Hexanic and chloroformic fractions also exhibit antifungal activity and two extracts and the fraction CE 2 antiparasitic activity against Leishmania donovani. All bioactive extracts and fractions assayed were also found to be cytotoxic to macrophages. In addition, the hexane and methane extracts show anti-inflammatory activity by suppressing the secretion of interleukine-6.

Effect of dosing quillaia saponin on waste water form marine products industries; Suisan kako danchi kara o haisui ni taisuru quillaia saponin no tenka no koka

Energy Technology Data Exchange (ETDEWEB)

Nagasaka, M. [Ibaraki University, Ibaraki (Japan). Faculty of Engineering

1995-12-20

For waste water treatment facilities of S marine products industrial complex, a demonstrative test was carried out on a waste water treatment method in which addition of biological activity promoter `quillaia saponin` and the aerobic/anaerobic method are combined. In the S marine products industrial complex, there are more than 100 plants which deal mostly with salt-preserved and boiled-fish-paste products. The plant is operated by the activated sludge method with the pretreatment pressurized floatation. The capacity of the aeration tank and concentration tank for the experiment was 2600m{sup 3} and 110m{sup 3}, respectively. The amount of saponin added was approximately 3mg/L for the amount of influent (raw waste water). The measurement items were transparency, SS, COD, BOD, n-hexane extracts (oil content), MLSS, etc. As a result of the experiment, it was found that the equipment of flocculant addition and pressurized floatation as pretreatment facilities is not necessary; the activated sludge treatment of even the waste water in which n-hexane extracts are more than 100mg/L is possible without the pretreatment; and the n-hexane extracts in the treated water is less than 2mg/L. 7 refs., 7 figs., 6 tabs.

The ultrasound-assisted aqueous extraction of rice bran oil.

Science.gov (United States)

Khoei, Maryam; Chekin, Fereshteh

2016-03-01

In this work, aqueous extraction of rice bran oil was done without and with ultrasound pretreatment. Key factors controlling the extraction and optimal operating conditions were identified. The highest extraction efficiency was found at pH=12, temperature of 45°C, agitation speed of 800rpm and agitation time of 15min, ultrasound treatment time of 70min and ultrasound treatment temperature of 25°C. Moreover, extraction yields were compared to ultrasound-assisted aqueous extraction and Soxhlet extraction. The results showed that the yield of rice bran oil at ultrasound-assisted aqueous extraction was close to the yield of oil extracted by hexane Soxhlet extraction. This result implied that the yield of rice bran oil was significantly influenced by ultrasound. With regard to quality, the oil extracted by ultrasound-assisted aqueous process had a lower content of free fatty acid and lower color imparting components than the hexane-extracted oil. Also, effect of parboiling of paddy on hexane and ultrasound-assisted aqueous extraction was studied. Both extraction methods gives higher percentage of oil from par boiled rice bran compared with raw rice bran. This may be due to the fact that parboiling releases the oil. Copyright © 2015 Elsevier Ltd. All rights reserved.

In vitro evaluation of antioxidant and antidiabetic activities of Syzygium densiflrum fruits

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Gopinath Krishnasamy

2015-11-01

Full Text Available Objective: To provide experimental support for the traditional knowledge of Syzygium densiflorum (S. densiflorum fruits. Methods: Powered S. densiflorum dried fruits were subjected to successive extraction with n-hexane, ethyl acetate, and ethanol using a Soxhlet extractor. Further, preliminary phytochemical screening was carried out with a series of tests. In vitro free radical scavenging was evaluated using total antioxidant estimation, 2,2-diphenyl-1-picrylhydrazyl radical, superoxide radical scavenging, and hydroxyl radical scavenging assays. Antidiabetic activity was estimated using α-amylase inhibition assay. Results: Preliminary phytochemical estimation confirmed the presence of alkaloids, flavonoids, sterols, terpenoids, anthocyanin, phenols, carbohydrates, fixed oils, and fats in fruits of S. densiflorum. Ethyl acetate and n-hexane extracts showed less free radical scavenging and α-amylase inhibition activity than ethanol extract. IC50 values of ethanol extracts for 2,2- diphenyl-1-picrylhydrazyl radical, superoxide radical, hydroxyl radical, lipid peroxidation, and α-amylase inhibition assays were found to be 0.01, 0.16, 0.66, 0.46, and 0.46 mg/mL respectively. Conclusions: In vitro evaluations confirmed the antioxidant and antidiabetic potential of S. densiflorum fruits. Ethanol extract of S. densiflorum fruits showed higher activity with statistical significance vs. ethyl acetate and n-hexane extracts.

Screening for bioactivity of Mutinus elegans extracts

Science.gov (United States)

Gajendiran, A.; Cyriac, RE; Abraham, J.

2017-11-01

Mutinus elegans is a species of fungi that is commonly called as Elegant Stinkhorn. The aim of this study was to screen the crude extracts of the fungus for phytochemical analysis, antimicrobial activity, antioxidant assay and anticancer activity. Extraction of the fungal sample in Soxhlet apparatus was done with n-hexane and methanol as the solvent. Stock solutions of the crude methanol extract were prepared and used for microbiological assay. Thin layer chromatography was performed in order to determine the number of active components in n-hexane, and methanol solvent system for the fungus Mutinus elegans. Further, antioxidant assay was performed using DPPH radical scavenging assay. The fungal sample was then tested for cytotoxicity assay against MG63 osteosarcoma cell lines. The antimicrobial assay of Mutinus elegans extract exhibited activity against five pathogens. The zone of inhibition was measured with respect to standard antibiotics. Gas chromatography and Mass spectrometry (GC/MS analysis), revealed the presence of dibromo-tetradecan-1-ol-acetate, 2-myristynoyl-glycinamide, fumaric acid, and cyclohexylmethyldecyl ester compounds were presented in methanol and n-hexane extract of Mutinus elegans. The present study concludes the presence of bioactive compound in the extract which exhibited antimicrobial and antioxidant activity in Mutinus elegans.

Bioactivity and Toxicity of Senna cana and Senna pendula Extracts

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J. A. Monteiro

2018-01-01

Full Text Available This work investigated the content of total polyphenolic compounds and flavonoids as well as their toxicity and larvicidal and acetylcholinesterase inhibitory activities. The antioxidant activities of two medicinal Senna species extracts (Senna cana and Senna pendula were also investigated. The ethanol extract of the leaves of S. cana and the ethanol extract of the branches of S. pendula presented the best performance in the DPPH/FRAP and ABTS/ORAC assays, respectively. For the inhibition of acetylcholinesterase, the hexane extract of the flowers of S. pendula presented the lowest IC50 value among the ethanol extracts of the leaves of S. cana and showed the best performance in some assays. The hexane extract of the leaves of S. pendula and the hexane extract of the branches of S. cana were moderate to Artemia salina Leach. In the quantification of phenols and flavonoids, the ethanol extract of the leaves of S. cana presented the best results. The ethanol extracts of the leaves of S. cana were found to be rich in antioxidants, phenolic compounds, and flavonoids. These results indicate the antioxidant potential of the extracts of Senna species and can be responsible for some of the therapeutic uses of these plants.

In vitro cytotoxicity of nonpolar constituents from different parts of kava plant (Piper methysticum).

Science.gov (United States)

Jhoo, Jin-Woo; Freeman, James P; Heinze, Thomas M; Moody, Joanna D; Schnackenberg, Laura K; Beger, Richard D; Dragull, Klaus; Tang, Chung-Shih; Ang, Catharina Y W

2006-04-19

Kava (Piper methysticum), a perennial shrub native to the South Pacific islands, has been used to relieve anxiety. Recently, several cases of severe hepatotoxicity have been reported from the consumption of dietary supplements containing kava. It is unclear whether the kava constituents, kavalactones, are responsible for the associated hepatotoxicity. To investigate the key components responsible for the liver toxicity, bioassay-guided fractionation was carried out in this study. Kava roots, leaves, and stem peelings were extracted with methanol, and the resulting residues were subjected to partition with a different polarity of solvents (hexane, ethyl acetate, n-butanol, and water) for evaluation of their cytotoxicity on HepG2 cells based on the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and lactate dehydrogenase and aspartate aminotransferase enzyme leakage assays. Organic solvent fractions displayed a much stronger cytotoxicity than water fractions for all parts of kava. The hexane fraction of the root exhibited stronger cytotoxic effects than fractions of root extracted with other solvents or extracts from the other parts of kava. Further investigations using bioassay-directed isolation and analysis of the hexane fraction indicated that the compound responsible for the cytotoxicity was flavokavain B. The identity of the compound was confirmed by (1)H and (13) C NMR and MS techniques.

Effect of Packaging Films on the Quality of Canola Oil under Photooxidation Conditions

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Hao Sun

2015-01-01

Full Text Available The objective of this study was to evaluate the influence of packaging films on the quality of canola oil which contains high concentration of fat under photooxidation condition and get the oxidation kinetics based on measuring the oxidation intensities including peroxide value, hexanal, and photosensitizer (chlorophyll. The canola oil was packaged by PET/CPP; KPET/PE was used for experiments. The change of light and oxygen transmission rate (OTR of PET/CPP which was considered as the typical fatty foods packaging film under different light intensities was also tested. The results show that the peroxide value increased rapidly under light conditions and fitted the zero order kinetics; also the oxygen transmission rate had great impact on it; hexanal fitted the zero order kinetic in oil whose package of low OTR generated a lot; however package in high OTR films changed very slowly that might be dependent on the performance of hexanal through plastic films. The degradation of chlorophyll fitted the first order kinetic and decreased quickly under light but was almost independent of OTR of transparent packaging material. Light reduced the oxygen barrier properties of the films, which should be considered as the photooxidation condition (and the photooxidation condition thus should be considered.

Mutagenicity and antimutagenicity of Salacia crassifolia (mart. Ex. Schult. G. Don. evaluated by Ames test

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C. C. Carneiro

2017-09-01

Full Text Available Abstract Salacia crassifolia (Mart. Ex. Schult. G. Don. is a bush which belongs to Celastraceae family and occurs specially in Brazilian Cerrado. Its leaves, stem, seeds and fruits are popularly used for several medicinal purposes, such as antitumoral, antirheumatic, anti-inflammatory and antimicrobial. In this study, the mutagenic and antimutagenic activities of S. crassifolia stem bark fractions (hexane, ethyl acetate and hydroalcoholic were evaluated by the Ames mutagenicity assay in Salmonella typhimurium TA98 and TA100 strains. By the obtained results, all S. crassifolia fractions did not significantly increase the number of prototrophic revertants for histidine (His+ in both S. typhimurium strains tested (p > 0.05, suggesting absence of mutagenicity. Regarding antimutagenicity, the fractions ethyl acetate and hydroalcoholic significantly decreased the number of His+ revertants colonies induced by positive control for strain TA98 (p < 0.05, demonstrating protection against mutagenicity induced by 4-nitroquinolile1-oxide, whereas the hexane fraction did not show antimutagenic effect in this strain. In the TA100 strain, all fractions of S. crassifolia protected DNA against the harmful action of sodium azide, and the hexane fraction exhibited the greatest protection in this work. Thus, it’s possible conclude that the fractions of S. crassifolia tested in this study could be used in chemoprevention.

Various Extraction Methods Influence the Adhesive Properties of Dried Distiller’s Grains and Solubles, and Press Cakes of Pennycress (Thlaspi arvense L. and Lesquerella [Lesquerella fendleri (A. Gary S. Watson], in the Fabrication of Lignocellulosic Composites

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Brent Tisserat

2018-04-01

Full Text Available Lignocellulosic composite (LC panels were fabricated using an adhesive matrix prepared from three different agricultural by-products: dried distillers grains with solubles (DDGS, pennycress (Thlaspi arvense L. press cake (PPC, or lesquerella [Lesquerella fendleri (A. Gary S. Watson] press cake (LPC reinforced with Paulownia elongata L. wood (PW particles. The goal in this study was to assess the mechanical properties of composites utilizing these low-cost matrix materials, which were subjected to various oil extraction methods. Three types of oil extraction methods were utilized: ethanol, supercritical CO2, and hexane, in order to generate matrix materials. These matrix materials were mixed with equal proportions of PW and hot pressed to generate panels. Overall, hexane extraction was the best method to enhance the mechanical properties of the matrices used to fabricate lignocellulosic composites. LPC’s produced a matrix that gave the resulting composite superior flexural properties compared to composites generated from DDGS and PPC matrices. The mechanical properties of composites generated from soy products (soybean meal flour or soy protein isolate were similar to those derived from DDGS, PPC, or LPC. The dimensional stability properties of LCs were improved when the hexane extraction method was employed, unlike with the other extraction methods that were used to generate matrices.

Plant compounds insecticide activity against Coleoptera pests of stored products

Energy Technology Data Exchange (ETDEWEB)

Moreira, Marcio Dionizio; Picanco, Marcelo Coutinho; Guedes, Raul Narciso Carvalho; Campos, Mateus Ribeiro de; Silva, Gerson Adriano; Martins, Julio Claudio [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Biologia Animal; br, picanco@ufv; br, guedes@ufv; br, mateusc3@yahoo com; br, agronomiasilva@yahoo com

2007-07-15

The objective of this work was to screen plants with insecticide activity, in order to isolate, identify and assess the bioactivity of insecticide compounds present in these plants, against Coleoptera pests of stored products: Oryzaephilus surinamensis L. (Silvanidae), Rhyzopertha dominica F. (Bostrichidae) and Sitophilus zeamais Mots. (Curculionidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetifolia (L.) R.Br.), jimson weed (Datura stramonium L.), baleeira herb (Cordia verbenacea L.), mint (Mentha piperita L.), wild balsam apple (Mormodica charantia L.), and billy goat weed or mentrasto (Ageratum conyzoides L.). The insecticide activity of hexane and ethanol extracts from those plants on R. dominica was evaluated. Among them, only hexane extract of A. conyzoides showed insecticide activity; the hexane extract of this species was successively fractionated by silica gel column chromatography, for isolation and purification of the active compounds. Compounds 5,6,7,8,3',4',5'-heptamethoxyflavone; 5,6,7,8,3'-pentamethoxy-4',5'-methilenedioxyflavone and coumarin were identified. However, only coumarin showed insecticide activity against three insect pests (LD{sub 50} from 2.72 to 39.71 mg g{sup -1} a.i.). The increasing order of insects susceptibility to coumarin was R. dominica, S. zeamais and O. surinamensis. (author)

Plant compounds insecticide activity against Coleoptera pests of stored products

International Nuclear Information System (INIS)

Moreira, Marcio Dionizio; Picanco, Marcelo Coutinho; Guedes, Raul Narciso Carvalho; Campos, Mateus Ribeiro de; Silva, Gerson Adriano; Martins, Julio Claudio; julioufv@yahoo.com.br

2007-01-01

The objective of this work was to screen plants with insecticide activity, in order to isolate, identify and assess the bioactivity of insecticide compounds present in these plants, against Coleoptera pests of stored products: Oryzaephilus surinamensis L. (Silvanidae), Rhyzopertha dominica F. (Bostrichidae) and Sitophilus zeamais Mots. (Curculionidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetifolia (L.) R.Br.), jimson weed (Datura stramonium L.), baleeira herb (Cordia verbenacea L.), mint (Mentha piperita L.), wild balsam apple (Mormodica charantia L.), and billy goat weed or mentrasto (Ageratum conyzoides L.). The insecticide activity of hexane and ethanol extracts from those plants on R. dominica was evaluated. Among them, only hexane extract of A. conyzoides showed insecticide activity; the hexane extract of this species was successively fractionated by silica gel column chromatography, for isolation and purification of the active compounds. Compounds 5,6,7,8,3',4',5'-heptamethoxyflavone; 5,6,7,8,3'-pentamethoxy-4',5'-methilenedioxyflavone and coumarin were identified. However, only coumarin showed insecticide activity against three insect pests (LD 50 from 2.72 to 39.71 mg g -1 a.i.). The increasing order of insects susceptibility to coumarin was R. dominica, S. zeamais and O. surinamensis. (author)

Contribution to the ethnopharmacological and anti-Helicobacter pylori knowledge of Cyrtocarpa procera Kunth (Anacardiaceae).

Science.gov (United States)

Escobedo-Hinojosa, Wendy Itzel; Del Carpio, Joel Díaz; Palacios-Espinosa, Juan Francisco; Romero, Irma

2012-08-30

Cyrtocarpa procera Kunth (Anacardiaceae) is a Mexican endemic tree; its bark has been traditionally employed in Mexico since prehispanic times to relieve digestive disorders. To perform an acute evaluation of the toxicity, gastroprotective, and anti-inflammatory properties, as well as the anti-Helicobacter pylori action of C. procera bark extracts, in order to determine polypharmalcological activities. Five different polarity extracts (hexanic, CH(2)Cl(2), CH(2)Cl(2)-MeOH, methanolic, and aqueous) were prepared. Each of them was evaluated in the following acute mice models: toxicity Lorke test, ethanol-induced gastric ulcer, TPA-induced ear edema; and the in vitro anti-H. pylori activity with a broth dilution method. None of the extracts were toxic under acute administration. The methanolic, hexanic, and aqueous extracts possess remarkable gastroprotective activity. All the extracts inhibit H. pylori growth, being the hexanic the most active, and only this one showed significant anti-inflammatory effect. This work demonstrates that C. procera bark has polypharmacological activities; which makes it a promising asset to the development of an integral treatment for gastritis or peptic ulcer related or not to H. pylori. Our findings contribute to the ethnopharmacological knowledge about this species. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Three-dimensional block copolymer nanostructures by the solvent-annealing-induced wetting in anodic aluminum oxide templates.

Science.gov (United States)

Chu, Chiang-Jui; Chung, Pei-Yun; Chi, Mu-Huan; Kao, Yi-Huei; Chen, Jiun-Tai

2014-09-01

Block copolymers have been extensively studied over the last few decades because they can self-assemble into well-ordered nanoscale structures. The morphologies of block copolymers in confined geometries, however, are still not fully understood. In this work, the fabrication and morphologies of three-dimensional polystyrene-block-polydimethylsiloxane (PS-b-PDMS) nanostructures confined in the nanopores of anodic aluminum oxide (AAO) templates are studied. It is discovered that the block copolymers can wet the nanopores using a novel solvent-annealing-induced nanowetting in templates (SAINT) method. The unique advantage of this method is that the problem of thermal degradation can be avoided. In addition, the morphologies of PS-b-PDMS nanostructures can be controlled by changing the wetting conditions. Different solvents are used as the annealing solvent, including toluene, hexane, and a co-solvent of toluene and hexane. When the block copolymer wets the nanopores in toluene vapors, a perpendicular morphology is observed. When the block copolymer wets the nanopores in co-solvent vapors (toluene/hexane = 3:2), unusual circular and helical morphologies are obtained. These three-dimensional nanostructures can serve as naontemplates for refilling with other functional materials, such as Au, Ag, ZnO, and TiO2 . © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Facile Fabrication and Characterization of a PDMS-Derived Candle Soot Coated Stable Biocompatible Superhydrophobic and Superhemophobic Surface.

Science.gov (United States)

Iqbal, R; Majhy, B; Sen, A K

2017-09-13

We report a simple, inexpensive, rapid, and one-step method for the fabrication of a stable and biocompatible superhydrophobic and superhemophobic surface. The proposed surface comprises candle soot particles embedded in a mixture of PDMS+n-hexane serving as the base material. The mechanism responsible for the superhydrophobic behavior of the surface is explained, and the surface is characterized based on its morphology and elemental composition, wetting properties, mechanical and chemical stability, and biocompatibility. The effect of %n-hexane in PDMS, the thickness of the PDMS+n-hexane layer (in terms of spin coating speed) and sooting time on the wetting property of the surface is studied. The proposed surface exhibits nanoscale surface asperities (average roughness of 187 nm), chemical compositions of soot particles, very high water and blood repellency along with excellent mechanical and chemical stability and excellent biocompatibility against blood sample and biological cells. The water contact angle and roll-off angle is measured as 160° ± 1° and 2°, respectively, and the blood contact angle is found to be 154° ± 1°, which indicates that the surface is superhydrophobic and superhemophobic. The proposed superhydrophobic and superhemophobic surface offers significantly improved (>40%) cell viability as compared to glass and PDMS surfaces.

Sperm Quality and Testicular Histomorphometry of Wistar Rats Supplemented with Extract and Fractions of Fruit of Tribulus terrestris L.

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Nelma Neylanne Pinho Muniz Oliveira

2015-12-01

Full Text Available ABSTRACT The aim of this study was to assess the sperm quality and testicular histomorphometry of Wistar rats supplemented with extract and fractions of fruits of Tribulus terrestris L. The ethanolic extract was obtained by dynamic maceration of spray-dried fruit. This extract was fractionated by liquid-liquid partition, using increasing polarity solvents. Twenty male rats were separated in four groups, with five rats in each group. The control was supplemented with distilled water, while the others were daily given the ethanolic extract, hexanic or aqueous fraction soluble in methanol in a dose of 42 mg.kg-1.day-1 for 70 days. Sperm was obtained from the right epididymal tail for the analysis of motility, count, morphology and viability. The testicular weight of groups supplemented with ethanolic extract and aqueous fraction soluble in methanol was higher when compared to the control. The gonadosomatic index increased in the group supplemented with ethanolic extract. The nuclear, cytoplasmic and individual volume of Leydig cells increased in supplementation with hexanic and aqueous fractions soluble in methanol. It was concluded that the extract influenced the spermatogenesis, while hexanic and aqueous fractions soluble in methanol promoted the changes in the intertubular compartment. Therefore, Tribulus terrestris did not improve the sperm quality of the rats.

The reducibility of heLa cell viability by Sargassum polycystum extracts

Science.gov (United States)

Firdaus, M.; Setijawati, D.; Islam, I.; Nursyam, H.; Kartikaningsih, H.; Yufidasari, H. S.; Prihanto, A. A.; Nurdiani, R.; Jaziri, A. A.

2018-04-01

Cervical cancer is the second largest cause of death-related cancer in women. The efficacy of cancer drugs is still low. Bioactive of brown seaweed has been studied by in vitro and in vivo as anticancer. The aim of this study was to evaluate the cytotoxicity of Sargassum polycystum extracts on HeLa cell, to recognize bioactive on extract and estimate the interaction between the bioactive and target protein. S. polycystum was found from Talango Island waters and HeLa cell was obtained from Indonesian Science Institute. Sample was extracted by ethanol, ethyl acetate and hexane, concentrated and finally, extracts were assayed on HeLa cell. The viability of this cell was quantified on ELISA-Reader. The bioactive compounds of the extract were elucidated by GC-MS. The interaction between bioactive and target protein was evaluated by using in silico method. The result showed that the lowest viability of HeLa cell on n-hexane extracts treatment. The n-hexane extract of this seaweed contained benzenepropanoic acid. This compound reduced HeLa cell viability by reducing of thrombin concentration. In conclusion, the benzene propanoic acid of S. polycystum was the cytotoxic agent and it is potential agent for anti-cervical cancer.

Phytotoxicity and biodirected fractionation of extracts of barks of Blepharocalyx salicifolius (Kunth O.Berg. (Myrtaceae

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Eduardo Habermann

2015-02-01

Full Text Available This study aimed to evaluate the phytotoxicity of extracts and fractions of barks of Blepharocalyx salicifolius on elongation of etiolated coleoptiles of Triticum aestivum (wheat. The extracts hexane (Hx, ethyl acetate (AcOET, and aqueous (H2O were obtained by means of exhaustive extraction with CH2Cl2/CH3OH and subsequent fractionation by partition chromatography coefficient. The extracts AcOET and Hx were fractionated by column chromatography by using organic solvents in increasing order of polarity, yielding 7 hexanic fractions and 6 ethylic acetate fractions. Subsequently, the fractions Hx1 and Hx5 were subfractionated by column chromatography. The extracts AcOET and Hx inhibited elongation of coleoptiles. Four ethylic acetate fractions inhibited elongation of coleoptiles at all concentrations. Five hexanic fractions inhibited elongation of coleoptiles, the fractions Hx5 and Hx1 fractions showed phytotoxic effects equivalent or superior to those observed by the herbicide GOAL® at the same concentrations. All subfractions obtained by means of fractionation of Hx1 inhibited elongation of coleoptiles. Six fractions obtained by means of fractionation of Hx5 inhibited elongation of coleoptiles at all concentrations. This study proves the phytotoxicity of extracts of barks of B. salicifolius, providing indications that they may act as promising natural herbicides.

Adsorption of halogenated hydrocarbons to microporous adsorbents. Pt. 1; Calorimetric measurement of the heat of adsorption of perfluoro-n-hexane and n-hexanes on zeolites of the faujasite type. Untersuchungen zur Adsorption von halogenierten Kohlenwasserstoffen an mikroporoesen Adsorbenzien. T. 1; Kalorimetrische Messung der Adsorptionswaerme von Perfluor-n-hexan and n-Hexan an Zeolithen vom Faujasityp

Energy Technology Data Exchange (ETDEWEB)

Stach, H [Adlershofer Umweltschutztechnik- und Forschungsgesellschaft mbH, Berlin (Germany); Sigrist, K; Ruediger, S; Gross, U

1993-06-01

The differential molar heats of adsorption were measured for n-C[sub 6]F[sub 14] and n-C[sub 6]H[sub 14] on two different zeolites of faujasite-type at 303 K by using a Calvet-type calorimeter. Comparing the heat curves of the perfluorinated compound on NaX and DY it is found that the molecular sieve with the smaller Si/Al ratio (higher electrostatic field) exhibits an about 10 kJ/mol larger heat of adsorption than the zeolite with the higher Si/Al ratio. The substitution of the H-atoms in the hydrocarbon by F-atoms brings about an increase of the adsorption heat for n-C[sub 6]F[sub 14] of 9.0 and 6.0 kJ/mol on the zeolites NaX and DY, respectively. Using a simple approximate equation the zero heats of adsorption of n-paraffins and perfluoro-n-paraffins from C[sub 1] to C[sub 7] were calculated. (orig.)

Potential Lipid-Lowering Effects of Eleusine indica (L) Gaertn. Extract on High-Fat-Diet-Induced Hyperlipidemic Rats.

Science.gov (United States)

Ong, Siew Ling; Nalamolu, Koteswara Rao; Lai, How Yee

2017-01-01

To date, anti-obesity agents based on natural products are tested for their potential using lipase inhibition assay through the interference of hydrolysis of fat by lipase resulting in reduced fat absorption without altering the central mechanisms. Previous screening study had indicated strong anti-obesity potential in Eleusine indica ( E. indica ), but to date, no pharmacologic studies have been reported so far. This study was performed to investigate the lipid-lowering effects of E. indica using both in vitro and in vivo models. The crude methanolic extract of E. indica was fractionated using hexane (H-Ei), dichloromethane (DCM-Ei), ethyl acetate (EA-Ei), butanol (B-Ei), and water (W-Ei). All the extracts were tested for antilipase activity using porcine pancreatic lipase. Because H-Ei showed the highest inhibition, it was further subjected to chemical profiling using high-performance liquid chromatography. Subsequently, oral toxicity analysis of H-Ei was performed [Organization for Economic Cooperation and Development guidelines using fixed dose procedure (No. 420)]; efficacy analysis was performed using high-fat diet (HFD)-induced hyperlipidemic female Sprague-Dawley rats. According to the toxicity and efficacy analyses, H-Ei did not demonstrate any noticeable biochemical toxicity or physiologic abnormalities and did not cause any tissue damage as per histologic analysis. Furthermore, H-Ei significantly reduced body weight and improved serum profile and did not show hepatotoxicity and nephrotoxicity based on the serum profile. Moreover, H-Ei alleviated HFD-induced hepatosteatosis and ameliorated induced adiposity in both visceral and subcutaneous adipose tissue. Our results demonstrate that H-Ei effectively improved hyperlipidemia. Further studies to explore its possibility as an alternative pharmacologic agent to treat obesity are warranted. Hexane extract of Eleusine indica (H-Ei) showed strong potential in the inhibition of porcine pancreatic lipase (27.01 �

Chemical kinetic insights into the ignition dynamics of n-hexane

KAUST Repository

Tingas, Alexandros; Wang, Zhandong; Sarathy, Mani; Im, Hong G.; Goussis, Dimitris A.

2017-01-01

Normal alkanes constitute a significant fraction of transportation fuels, and are the primary drivers of ignition processes in gasoline and diesel fuels. Low temperature ignition of n-alkanes is driven by a complex sequence of oxidation reactions

Evaluation of the anti-inflammatory properties of the hexane extract ...

African Journals Online (AJOL)

Maj Obaseki

2016-08-26

Aug 26, 2016 ... side effects to substitute for these chemical therapeutics. The use of plants ...... Occurrence, Structure and Role in the Human Diet. UK: Blackwell .... 1. The effect of histamine and serotonin on vascular permeability: an electron.

Analgesic and Anti-inflammatory Profile of n-Hexane Fraction of ...

African Journals Online (AJOL)

HP

inflammatory activities (carrageenan-induced and histamine-induced edema models) in BALB/c mice. Results: VBHF exhibited significant (p ... The analgesic effect of VBHF was dose-dependent in acetic acid pain model while the extract was a weak ... In Pakistan, it is found in Swat, Hazara and. Dir and used as antipyretic, ...

Separation of Azeotropic Mixture Acetone + Hexane by Using Polydimethylsiloxane Membrane.

Czech Academy of Sciences Publication Activity Database

Randová, A.; Bartovská, L.; Kačírková, Marie; Ledesma, Oscar Iván Hernández; Červenková Šťastná, Lucie; Izák, Pavel; Žitková, Andrea; Friess, K.

2016-01-01

Roč. 170, OCT 1 (2016), s. 256-263 ISSN 1383-5866 R&D Projects: GA MŠk(CZ) LD14094 Institutional support: RVO:67985858 Keywords : azeotropic mixture * PDMS membrane * pervaporation Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 3.359, year: 2016

Oxidative cracking of n-hexane: a catalytic pathway to olefins

NARCIS (Netherlands)

Boyadjian, C.A.

2010-01-01

Steam cracking, the major, current existing route for light olefin production, is the most energy consuming process in the chemical industry. The need for an energy efficient processes, urged substantial research work for the development of new catalytic technologies for light olefin production.

Effect of methanol, n-hexane and aqueous extract of Irvingia ...

African Journals Online (AJOL)

children below 5 years in Asia, Latin America and Africa resulting in 4-5 million deaths. (Abdullahi et al. ... two years of life and declines as a child grows older. Mortality from diarrhoea has declined over the past two ... powder was weighed using an electric weighing balance by Kern ALS 220 – 4. The powder was then ...

The Effect Of Hexane Extract Of Azidirachta indica Leaves On ...

African Journals Online (AJOL)

Improved Neubauer's chamber was used to determine the testicular sperm reserve. The right testis, liver, kidney and spleen were routinely prepared for light microscopy. The control mice had significantly higher (P<0.05) testicular sperm reserve than the treatment group mice, which received the highest dose of the extract.

Evaluation of the anti-inflammatory properties of the hexane extract ...

African Journals Online (AJOL)

The extract was finally subjected to GC/MS analysis for the tentative identification of the phytochemical constituents. Phytochemical analysis of the extract revealed the presence of saponin, phenol, flavonoid, tannin, terpenoid and sterol. This extract showed the ability to inhibit thermally-induced protein denaturation and ...

Evaluation of the anti-inflammatory properties of the hexane extract ...

African Journals Online (AJOL)

Maj Obaseki

2016-08-26

Aug 26, 2016 ... and human red blood cell (HRBC) membrane stabilization assays. ... bonariensis affirms the anti-inflammatory property of the plant and the phytochemicals ..... Plasma for liver function tests was obtained by centrifuging the.

Compendium of shock wave data. Introduction. Section A1. Elements

International Nuclear Information System (INIS)

van Thiel, M.; Shaner, J.; Salinas, E.

1977-06-01

This volume lists thermodynamic data for inorganic compounds and hydrocarbons. Binary and more complex compounds (including minerals) are listed; among the hydrocarbons are anthracene, benzene, hexane, paraffin, polyethylene, and polystyrene

THERMODYNAMIC PARAMETERS OF SOLUTIONS OF ...

African Journals Online (AJOL)

2014-06-30

Jun 30, 2014 ... Physical Chemistry Laboratory, Department of Chemistry, ... The solubility of Sildenafil citrate in some organic solvents; hexane, ... dichloroethane were analytical grade reagents, which were purified by fractional distillation.

Artificial Neural Network Analysis of Xinhui Pericarpium Citri ...

African Journals Online (AJOL)

Methods: Artificial neural networks (ANN) models, including general regression neural network (GRNN) and multi-layer ... N-hexane (HPLC grade) was purchased from. Fisher Scientific. ..... Simultaneous Quantification of Seven Flavonoids in.

Susceptibility of Aedes aegypti pupae to neem seed kernal extracts ...

African Journals Online (AJOL)

Azadirachta indica) seed kernel extracts (NSKE) on Aedes aegypti. The neem seed kernel powder was sequentially extracted with hexane, benzene, ethyl acetate, acetone, DMSO, 2-propanol, ethanol, methanol and dstiledwater.

Combinatorial Analysis of Functional Interfaces and Surfaces Generated Via Dip-Pen Nanolithography

National Research Council Canada - National Science Library

Higgins, Thomas B

2006-01-01

.... Various chemical compounds spanning a range of hydrophobicities and meniscus solubilities were used as inks in DPN and deposited in a variety of solvent atmospheres such as ethanol, methanol, hexanes...

Aggregate development in C 60/N-methyl-2-pyrrolidone solution and its mixture with water as revealed by extraction and mass spectroscopy

Science.gov (United States)

Kyzyma, O. A.; Korobov, M. V.; Avdeev, M. V.; Garamus, V. M.; Snegir, S. V.; Petrenko, V. I.; Aksenov, V. L.; Bulavin, L. A.

2010-06-01

The aggregate development in C 60/N-methyl-2-pyrrolidone (C 60/NMP) solution with time is studied by the extraction (hexane) and mass spectroscopy. It is shown that only molecular C 60 in NMP is extracted in hexane, which makes it possible to follow a change in the concentration of non-aggregated fullerene in C 60/NMP during the aggregate growth. It is concluded that almost all fullerene dissolved in NMP is in the aggregates after one month. The reorganization of the aggregates is detected when water is added to the aggregated solution C 60/NMP. Both methods prove that in this case individual fullerene molecules are detached from the aggregates, which contradicts somewhat to complete insolubility of C 60 in water.

Packaging and irradiation effects on lipid oxidation and volatiles in pork patties

International Nuclear Information System (INIS)

Ahn, D.U.; Olson, D.G.; Lee, J.I.; Jo, C.; Wu, C.; Chen, X.

1998-01-01

Raw-meat patties were prepared from three pork muscles, irradiated in different packaging environments, and stored for 0 or 3 days before cooking. Lipid oxidation by-products were formed in the raw meat during storage and the baseline lipid oxidation data of raw meat was used to measure the progression of lipid oxidation after cooking. Thiobarbituric acid-reactive substances (TBARS) and volatiles data indicated that preventing oxygen exposure after cooking was more important for cooked meat quality than packaging, irradiation, or storage conditions of raw meat. Propanal, pentanal, hexanal, 1-pentanol, and total volatiles correlated highly (P 0.01) with TBARS values of cooked meat. Hexanal and total volatiles represented the lipid oxidation status better than any other individual volatile components

Solvent Extraction and Separation of Chromium(III) and (V I) in Aqueous Solutions with Trioctylphosphine Oxide

International Nuclear Information System (INIS)

Sekine, T.; Yamada, M.

1999-01-01

The solvent extraction of chromium(III) and (V I) in aqueous solutions with a solvating type extractant, trioctylphosphine oxide(TOPO), in hexane is studied. Kinetically inert Cr 3+ is extracted from 1 mol dm -3 sodium perchlorate solution very quickly and quantitatively as Cr(H 2 O · TOPO) 6 3+ (CIO 4 -) 3 . Chromium(V I) in hydrochloric acid is extracted effectively as the H 2 CrO $ (H CI) n centre dot TOPO m species ( m = 2 or 3, n = 0 to 2) and the distribution ratio increased by an increase in the acid concentration. From these, a procedure is proposed for the extraction of both chromium(V I) and chromium(III) in aqueous solution separately with 0.1 mol dm -3 TOPO in hexane

Antiamoebic activity of marine sponge Haliclona exigua (Krikpatrick

Directory of Open Access Journals (Sweden)

V Lakshmi

2009-03-01

Full Text Available The methanol and methanol-chloroform (1:1 extracts of the freshly collected Haliclona exigua showed minumim inhibitory concentration (MIC of 125 ug/ml and 250 ug/ml respectively in in vitro studies, but when both of these were tested in vivo in rats, only methanol-chloroform showed 80% inhibition of trophozoites at the dose of 900 mg/kg body weight against Entamoeba histolytica. Therefore only methanol-chloroform extract was further fractionated into four fractions (hexane, chloroform, n-butanol soluble and n-butanol insoluble fractions. Out of these, only hexane and n-butanol soluble fractions showed 80% inhibition of trophozoites at 900 mg/kg dose. Further the chromatography of the n-butanol fraction yielded araguspongin-C which showed promising results at different doses.

Chemical composition and antibacterial activity of extracts of freshwater green algae, Cladophora glomerata Kützing andMicrospora floccosa (Vaucher Thuret

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Ratiphan Laungsuwon

2014-12-01

Full Text Available Freshwater macroalgae, Cladophora glomerata Kützing and Microspora floccosa (Vaucher Thuret, harvested from Nan River in northern Thailand, were extracted with hexane, ethyl acetate, methanol and hot water. The extracts were screened for antibacterial activities. Hexane and ethyl acetate extracts of both algae showed the activities against Bacillus cereus and Vibrio parahaemolyticus. The extracts were further separated using column chromatography and chemically characterized by GC–MS in order to be tentative identify the compounds responsible for such activities. The main compositions were fatty acid and other organic compounds, in which have not been reported in these algae. These results indicate that extracts of C. glomerata and M. floccosa exhibited appreciable antimicrobial activity and could be a source of valuable bioactive materials for health products.

Metabolic Activity Interferometer: A Powerful Tool for Testing Antibiotics

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Rachel R. P. Machado

2012-01-01

Full Text Available It is demonstrated that the efficiency of antibiotics can be tested using an interferometric method. Two antibiotics were used as models to show that an interferometric method to monitor the metabolic activity of slowly growing bacteria can be a safer method to judge antimicrobial properties of substances than conventional methods. The susceptibility of Mycobacterium bovis to hexane extract of Pterodon emarginatus and to the well-known antibiotic rifampicin was tested with the interferometric method and with the conventional microplate method. The microplate method revealed a potential activity of hexane extract against M. bovis. However, the interferometric method showed that the action of this substance is rather limited. Also in the case of rifampicin, the interferometric method was able to detect resistant bacteria.

Anti-inflammatory activity of Heliotropium strigosum in animal models.

Science.gov (United States)

Khan, Haroon; Khan, Murad Ali; Gul, Farah; Hussain, Sajjid; Ashraf, Nadeem

2015-12-01

The current project was designed to evaluate the anti-inflammatory activity of crude extract of Heliotropium strigosum and its subsequent solvent fractions in post carrageenan-induced edema and post xylene-induced ear edema at 50, 100, and 200 mg/kg intraperitoneally. The results revealed marked attenuation of edema induced by carrageenan injection in a dose-dependent manner. The ethyl acetate fraction was most dominant with 73.33% inhibition followed by hexane fraction (70.66%). When the extracts were challenged against xylene-induced ear edema, again ethyl acetate and hexane fractions were most impressive with 38.21 and 35.77% inhibition, respectively. It is concluded that various extracts of H. strigosum possessed strong anti-inflammatory activity in animal models. © The Author(s) 2012.

Liquid- and Gas-Phase Diffusion of Ferrocene in Thin Films of Metal-Organic Frameworks

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Wencai Zhou

2015-06-01

Full Text Available The mass transfer of the guest molecules in nanoporous host materials, in particular in metal-organic frameworks (MOFs, is among the crucial features of their applications. By using thin surface-mounted MOF films in combination with a quartz crystal microbalance (QCM, the diffusion of ferrocene vapor and of ethanolic and hexanic ferrocene solution in HKUST-1 was investigated. For the first time, liquid- and gas-phase diffusion in MOFs was compared directly in the identical sample. The diffusion coefficients are in the same order of magnitude (~10−16 m2·s−1, whereas the diffusion coefficient of ferrocene in the empty framework is roughly 3-times smaller than in the MOF which is filled with ethanol or n-hexane.

Liquid- and Gas-Phase Diffusion of Ferrocene in Thin Films of Metal-Organic Frameworks

Science.gov (United States)

Zhou, Wencai; Wöll, Christof; Heinke, Lars

2015-01-01

The mass transfer of the guest molecules in nanoporous host materials, in particular in metal-organic frameworks (MOFs), is among the crucial features of their applications. By using thin surface-mounted MOF films in combination with a quartz crystal microbalance (QCM), the diffusion of ferrocene vapor and of ethanolic and hexanic ferrocene solution in HKUST-1 was investigated. For the first time, liquid- and gas-phase diffusion in MOFs was compared directly in the identical sample. The diffusion coefficients are in the same order of magnitude (~10−16 m2·s−1), whereas the diffusion coefficient of ferrocene in the empty framework is roughly 3-times smaller than in the MOF which is filled with ethanol or n-hexane.

Biodiesel production by direct transesterification of microalgal biomass with co-solvent.

Science.gov (United States)

Zhang, Yan; Li, Ya; Zhang, Xu; Tan, Tianwei

2015-11-01

In this study, a direct transesterification process using 75% ethanol and co-solvent was studied to reduce the energy consumption of lipid extraction process and improve the conversion yield of the microalgae biodiesel. The addition of a certain amount of co-solvent (n-hexane is most preferable) was required for the direct transesterification of microalgae biomass. With the optimal reaction condition of n-hexane to 75% ethanol volume ratio 1:2, mixed solvent dosage 6.0mL, reaction temperature 90°C, reaction time 2.0h and catalyst volume 0.6mL, the direct transesterification process of microalgal biomass resulted in a high conversion yield up to 90.02±0.55wt.%. Copyright © 2015 Elsevier Ltd. All rights reserved.

Phytochemical and biological characterization of Periploca aphyla ...

African Journals Online (AJOL)

Dr.R Ali Khan

2012-07-10

Jul 10, 2012 ... quantity of flavonoids in methanolic extract of P. hysterophorus which turned down gradually in n- hexane extract ... Sample Flavonoids Alkaloids Terpenoids Coumarins Saponins ... Science and Technology Bannu, Pakistan.

Rate Constants for the Reactions of Hydroxyl Radical with Several Alkanes, Cycloalkanes, and Dimethyl Ether

Science.gov (United States)

DeMore, W.; Bayes, K.

1998-01-01

Relative rate experiements were used to measure rate constants and temperature denpendencies of the reactions of OH with propane, n-butane, n-pentane, n-hexane, cyclopropane, cyclobutane, cyclopentane, and dimethyl ether.

Analgesic and Anti-Inflammatory Activities of an Ethanol Extract of ...

African Journals Online (AJOL)

Samuel Olaleye

(nociception) induced by acetic acid, formalin and hot plate. ... in hexane, chloroform, ethyl acetate and methanol. Each aqueous ... (Unfailing Veterinary Service, Uyo, Nigeria) and water ..... neurokinin A and vasoactive intestinal peptide, which.

Unusual dewetting of thin polymer films in liquid media containing a poor solvent and a nonsolvent.

Science.gov (United States)

Xu, Lin; Sharma, Ashutosh; Joo, Sang Woo; Liu, Hui; Shi, Tongfei

2014-12-16

We investigate the control of pattern size and kinetics in spontaneous dewetting of thin polymer films (polystyrene) that are stable to thermal annealing by annealing in a poor solvent (acetone)/nonsolvent (ethanol or n-hexane) liquid mixture. Dewetting occurs by the formation and growth of circular holes that coalesce to form droplets. The influence of the nature and the volume fraction of the nonsolvents on the contact angle of polymer droplets, number density of holes, and the kinetics of holes formation and growth is studied. Addition of ethanol greatly increases the hole density and slows down the kinetics substantially, while affecting only a small change in wettability. n-Hexane addition shows an interesting nonmonotonic response in decreasing the hole density and contact angle in the volume fraction range of 0-0.3 but an opposite effect beyond that. Although the two nonsolvents chosen cannot by themselves induce dewetting, their relative affinity for the solid substrate vis-à-vis acetone can strongly influence the observed dewetting scenarios that are not understood by the existing theoretical considerations. n-Hexane, for example, has great affinity for silicon substrate. In addition to the changes in wettability, viscosity, and film interfacial tension engendered by the nonsolvents, the possibility of the formation of adsorbed liquid layers at the substrate-polymer interface, which can modify the interfacial friction and slippage, needs to be considered.

Antioxidant Activity and Volatile and Phenolic Profiles of Essential Oil and Different Extracts of Wild Mint (Mentha longifolia from the Pakistani Flora

Directory of Open Access Journals (Sweden)

Tahseen Iqbal

2013-01-01

Full Text Available The antioxidant activity and free radical scavenging capacity of the essential oil and three different extracts of wildly grown Mentha longifolia (M. longifolia were studied. The essential oil from M. longifolia aerial parts was isolated by hydrodistillation technique using Clevenger-type apparatus. The extracts were prepared with three solvents of different polarity (n-hexane, dichloromethane, and methanol using Soxhlet extractor. Maximum extract yield was obtained with methanol (12.6 g/100 g while the minimum with dichloromethane (3.50 g/100 g. The essential oil content was found to be 1.07 g/100 g. A total of 19 constituents were identified in the M. longifolia oil using GC/MS. The main components detected were piperitenone oxide, piperitenone, germacrene D, borneol, and β-caryophyllene. The total phenolics (TP and total flavonoids (TF contents of the methanol extract of M. longifolia were found to be significantly higher than dichloromethane and hexane extracts. The dichloromethane and methanol extracts exhibited excellent antioxidant activity as assessed by 2,2′-diphenyl-1-picrylhydrazyl (DPPH free radical scavenging ability, bleaching β-carotene, and inhibition of linoleic acid peroxidation assays. The essential oil and hexane extract showed comparatively weaker antioxidant and free radical scavenging activities. The results of the study have validated the medicinal and antioxidant potential of M. longifolia essential oil and extracts.

Determination of a method for extraction of coenzyme Q10 in human plasma: optimization of the use of surfactants and other variables

Directory of Open Access Journals (Sweden)

Claudia Cristina Ferreiro-Barros

2012-06-01

Full Text Available Objective: To establish a routine for the extraction of the total levelsof CoQ10 in human plasma through the Ultra High Performance LiquidChromatography (UHPLC. Methods: Two extraction protocolswere tested: a methanol: hexane and b 1-propanol. The followingparameters were analyzed: extraction temperature (19ºC and 4ºC,extraction tubes (glass and polypropylene, and surfactants (SDS,Triton X-100, Tween-20 at different concentrations, i.e., 1%,3%, 5% and 10%. Results: The results showed that the methodof extraction of CoQ10 in a sample of human plasma at 4ºC, usingsolvents methanol: hexane (85:15, v/v in the presence of surfactantTween-20 at 3% and polypropylene tubes showed better efficiencyand reproducibility when compared to the method with 1-propanol.Conclusion: By the analyses performed, it was possible to observethat the addition of the surfactant Tween-20 promoted an increasein the recovery of CoQ10 by the methanol:hexane extraction method.This method showed good reproducibility, with a low coefficient ofvariation and high sensitivity, since CoQ10 was detected in samplesof plasma of a control individual using a UV-type detector. The useof UHPLC equipment allowed a total analysis with total run time of3.5 minutes, enabling the rapid achievement of results, consideredmandatory for laboratory routines.

The effect of solvents on the stabilities (color and Fe) of anthocyanin isolated from the red-color-melinjo peels

Energy Technology Data Exchange (ETDEWEB)

Tarmizi, Ermiziar, E-mail: uph-ermi@yahoo.com, E-mail: ermitarmizi@gmail.com; Saragih, Raskita, E-mail: raskitasaragih@yahoo.com [Indonesia Institute of Technology (ITI), Raya PuspiptekSerpong, Tangerang Banten 15320 (Indonesia); Lalasari, Latifa Hanum, E-mail: ifa-sari@yahoo.com, E-mail: lati003@lipi.go.id [Research Centre for Metallurgy and Material, Indonesian Institute of Sciences (LIPI), KawasanPuspiptekSerpong, Tangerang Selatan 15314 (Indonesia)

2015-12-29

Anthocyanin from the red-color-melinjo peels could be isolated using a polar solvent (ethanol) [ermiziar, 2010]. The amount of hydrocarbons in the structure of anthocyanin might cause that anthocyanin could be isolated using a non polar solvent. The purpose of research is to isolate anthocyanin using non polar solvents (hexane and petroleum ether) with maceration steps for 24 hours and separate solvents using rotary evaporator equipment. The stability of anthocyanin could be observed every week (1,2,3 and 4 weeks) in various environmental conditions (with or without light in refrigerator and open or closed storage). The characterization of anthocyanin was analyzed with visual (physic photo) and or using equipments such as Fourier Transform Infrared Spectroscopy (FTIR) for determining functional groups, Ultraviolet–Visible Spectroscopy (UV/Vis) with 500-550 nm wavelengths for deciding absorption of anthocyanin and atomic absorption spectroscopy (AAS) for analyzing Fe element. The result showed that anthocyanin isolation with hexane solvent has yield higher than petroleum eter solvent. From the results of physic observation for 4 weeks looked that there are changing colors of samples significant after 3 and 4 weeks in cooler with or without light. The stability of anthocyanin color was the best on the storage time until 2 weeks using hexane solvent in refrigerator and closed condition that it has absorption of 0.6740 with 500 nm wavelengths and Fe concentration 6.29 ppm.

Diterpenoids and flavonoids from the fruits of Vitex agnus-castus and antioxidant activity of the fruit extracts and their constituents.

Science.gov (United States)

Hajdú, Zsuzsanna; Hohmann, Judit; Forgo, Peter; Martinek, Tamás; Dervarics, Máté; Zupkó, István; Falkay, György; Cossuta, Daniel; Máthé, Imre

2007-04-01

From the n-hexane fraction of the fruits of Vitex agnus-castus, two labdane-type diterpenes, vitetrifolin B and C, were isolated by means of multiple chromatographic separations, together with the previously identified rotundifuran, vitexilactone and the sesquiterpene spathulenol. From the EtOAc fraction, eupatorin was identified for the first time, besides the known casticin, penduletin, vitexin and orientin. The n-hexane, EtOAc and MeOH-H(2)O fractions of the MeOH extract of Agni-casti fructus were subjected to in vitro antioxidant assays. The EtOAc extract displayed a significant concentration-dependent effect when tested by 1,1-diphenyl-2-picrylhydrasyl (DPPH) free radical assay (IC(50) = 68 microg/mL) and against the autooxidation of a standard rat brain homogenate (IC(50) = 14 microg/mL). The MeOH-H(2)O fraction was less active with 3643 microg/mL (DPPH test) and IC(50) = 125 microg/mL (rat brain homogenate), while the n-hexane phase proved to be inactive. The main flavonoid constituents of the EtOAc extract, casticin, vitexin and orientin were assayed for antioxidant activity and found that only casticin possesses a marked lipid peroxidation inhibitory effect (IC(50) = 0.049 mm) compared with that of the positive control ascorbic acid (IC(50) = 0.703 mm).

Plant compounds insecticide activity against Coleoptera pests of stored products

Energy Technology Data Exchange (ETDEWEB)

Moreira, Marcio Dionizio; Picanco, Marcelo Coutinho; Guedes, Raul Narciso Carvalho; Campos, Mateus Ribeiro de; Silva, Gerson Adriano; Martins, Julio Claudio [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Biologia Animal]. E-mail: marcio.dionizio@gmail.com; picanco@ufv.br; guedes@ufv.br; mateusc3@yahoo.com.br; agronomiasilva@yahoo.com.br

2007-07-15

The objective of this work was to screen plants with insecticide activity, in order to isolate, identify and assess the bioactivity of insecticide compounds present in these plants, against Coleoptera pests of stored products: Oryzaephilus surinamensis L. (Silvanidae), Rhyzopertha dominica F. (Bostrichidae) and Sitophilus zeamais Mots. (Curculionidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetifolia (L.) R.Br.), jimson weed (Datura stramonium L.), baleeira herb (Cordia verbenacea L.), mint (Mentha piperita L.), wild balsam apple (Mormodica charantia L.), and billy goat weed or mentrasto (Ageratum conyzoides L.). The insecticide activity of hexane and ethanol extracts from those plants on R. dominica was evaluated. Among them, only hexane extract of A. conyzoides showed insecticide activity; the hexane extract of this species was successively fractionated by silica gel column chromatography, for isolation and purification of the active compounds. Compounds 5,6,7,8,3',4',5'-heptamethoxyflavone; 5,6,7,8,3'-pentamethoxy-4',5'-methilenedioxyflavone and coumarin were identified. However, only coumarin showed insecticide activity against three insect pests (LD{sub 50} from 2.72 to 39.71 mg g{sup -1} a.i.). The increasing order of insects susceptibility to coumarin was R. dominica, S. zeamais and O. surinamensis. (author)

Analysis of Benzo[a]pyrene in Vegetable Oils Using Molecularly Imprinted Solid Phase Extraction (MISPE Coupled with Enzyme-Linked Immunosorbent Assay (ELISA

Directory of Open Access Journals (Sweden)

Michael Pschenitza

2014-05-01

Full Text Available This paper describes the development of a molecularly imprinted polymer-based solid phase extraction (MISPE method coupled with enzyme-linked immunosorbent assay (ELISA for determination of the PAH benzo[a]pyrene (B[a]P in vegetable oils. Different molecularly imprinted polymers (MIPs were prepared using non-covalent 4-vinylpyridine/divinylbenzene co-polymerization at different ratios and dichloromethane as porogen. Imprinting was done with a template mixture of phenanthrene and pyrene yielding a broad-specific polymer for PAHs with a maximum binding capacity (Q of ~32 μg B[a]P per 50 mg of polymer. The vegetable oil/n-hexane mixture (1:1, (v/v was pre-extracted with acetonitrile, the solvent evaporated, the residue reconstituted in n-hexane and subjected to MISPE. The successive washing with n-hexane and isopropanol revealed most suitable to remove lipid matrix constituents. After elution of bound PAHs from MISPE column with dichloromethane, the solvent was evaporated, the residue reconstituted with dimethyl sulfoxide and diluted 100-fold with methanol/water (10:90, (v/v for analysis of B[a]P equivalents with an ELISA. The B[a]P recovery rates in spiked vegetable oil samples of different fatty acid composition were determined between 63% and 114%. The presence of multiple PAHs in the oil sample, because of MIP selectivity and cross-reactivity of the ELISA, could yield overestimated B[a]P values.

Antiproliferative Activities of Bouea Macrophylla Seed Extracts

International Nuclear Information System (INIS)

Arapoc, D.J.; Mohamed Zaffar Ali Mohamed Amiroudine; Zainah Adam; Rosniza Razali; Shafii Khamis

2016-01-01

Bouea macrophylla or commonly known as kundang fruit in Malaysia is a tropical fruit tree native to Southeast Asia. This plant belongs to the family Anacardiaceae which are cultivated for their edible fruits, seeds and medicinal compounds. The present study was conducted to evaluate the anti proliferation activities of aqueous, methanolic, chloroform and hexane extracts from the seed of B. macrophylla. The extracts were screened on human squamous cell carcinoma (HTB-43), breast cancer (MCF7) and (MDA-MB-231) cell lines by using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Most effective concentration were screened for apoptosis induction in cells using Hoechst stain. Our present study has shown that aqueous, methanolic, chloroform dan hexane extracts exhibited promising inhibition activity against HTB43 cell lines with the IC50 values were 29.32±5.80, 18.65±2.94, 21.14±6.97 and 34.36±16.50 μg/ mL, respectively. Meanwhile, only hexane extract showed inhibition against MCF7 (59.07±5.76) and MDA-MB-231(123.35±28.65). Besides that, the results also indicate that promising anticancer activity and causes loss in cancer cell viability by activating the apoptotic process. These findings suggest that B. macrophylla may have novel therapeutic applications for the treatment of different cancer types. (author)

The effect of solvents on the stabilities (color and Fe) of anthocyanin isolated from the red-color-melinjo peels

International Nuclear Information System (INIS)

Tarmizi, Ermiziar; Saragih, Raskita; Lalasari, Latifa Hanum

2015-01-01

Anthocyanin from the red-color-melinjo peels could be isolated using a polar solvent (ethanol) [ermiziar, 2010]. The amount of hydrocarbons in the structure of anthocyanin might cause that anthocyanin could be isolated using a non polar solvent. The purpose of research is to isolate anthocyanin using non polar solvents (hexane and petroleum ether) with maceration steps for 24 hours and separate solvents using rotary evaporator equipment. The stability of anthocyanin could be observed every week (1,2,3 and 4 weeks) in various environmental conditions (with or without light in refrigerator and open or closed storage). The characterization of anthocyanin was analyzed with visual (physic photo) and or using equipments such as Fourier Transform Infrared Spectroscopy (FTIR) for determining functional groups, Ultraviolet–Visible Spectroscopy (UV/Vis) with 500-550 nm wavelengths for deciding absorption of anthocyanin and atomic absorption spectroscopy (AAS) for analyzing Fe element. The result showed that anthocyanin isolation with hexane solvent has yield higher than petroleum eter solvent. From the results of physic observation for 4 weeks looked that there are changing colors of samples significant after 3 and 4 weeks in cooler with or without light. The stability of anthocyanin color was the best on the storage time until 2 weeks using hexane solvent in refrigerator and closed condition that it has absorption of 0.6740 with 500 nm wavelengths and Fe concentration 6.29 ppm

Understanding structure-stability relationships of Candida antartica lipase B in ionic liquids.

Science.gov (United States)

De Diego, Teresa; Lozano, Pedro; Gmouh, Said; Vaultier, Michel; Iborra, José L

2005-01-01

Two different water-immiscible ionic liquids (ILs), 1-ethyl-3-methylimidizolium bis(trifluoromethylsulfonyl)imide and butyltrimethylammonium bis(trifluoromethylsulfonyl)imide, were used for butyl butyrate synthesis from vinyl butyrate catalyzed by Candida antarctica lipase B (CALB) at 2% (v/v) water content and 50 degrees C. Both the synthetic activity and stability of the enzyme in these ILs were enhanced as compared to those in hexane. Circular dichroism and intrinsic fluorescence spectroscopic techniques have been used over a period of 4 days to determine structural changes in the enzyme associated with differences in its stability for each assayed medium. CALB showed a loss in residual activity higher than 75% after 4 days of incubation in both water and hexane media at 50 degrees C, being related to great changes in both alpha-helix and beta-strand secondary structures. The stabilization of CALB, which was observed in the two ILs studied, was associated with both the maintenance of the 50% of initial alpha-helix content and the enhancement of beta-strands. Furthermore, intrinsic fluorescence studies clearly showed how a classical enzyme unfolding was occurring with time in both water and hexane media. However, the structural changes associated with the incubation of the enzyme in both ILs might be attributed to a compact and active enzyme conformation, resulting in an enhancement of the stability in these nonaqueous environments.

Antimicrobial Efficacy of Salvadora persica Extracts on a Monospecies Biofilm on Orthodontic Brackets In Vitro.

Science.gov (United States)

Halawany, Hassan S; Abraham, Nimmi B; Siddiqui, Yunus M; Balto, Hanan A; Jacob, Vimal

2016-01-01

The oral cavity is a rich ecosystem with a plethora of microorganisms, and different components of fixed orthodontic appliances may contribute to a shift in the balance of oral ecology. The purpose of this study was to investigate the antimicrobial potential of hexane and ethanol extracts of Salvadora persica on a monospecies biofilm model established on orthodontic brackets in vitro. Streptococcus mutans biofilm was formed on mini diamond orthodontic brackets following three days of anaerobic incubation at 37˚C. The bacterial cell viability of this biofilm was measured after their exposure to saline, hexane extract of S. persica, ethanol extract of S. persica and 0.2% chlorhexidine using 3-(4, 5-dimethylthiazol- 2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) assay. On half of the brackets, the colony forming units (CFU) were counted. Both experiments were performed in triplicate. The absorbance values obtained from the MTS reduction assay after exposure to the different test agents showed a decline in the bacterial cell viability of the S. mutans biofilm as follows: chlorhexidine (+)0.05). The CFU counts of S. mutans obtained from chlorhexidine exposure were lower than from hexane and ethanol extracts. S. persica extracts were found to have antimicrobial effects on S. mutans biofilm established in vitro on orthodontic brackets suggestive of its potential use as an oral antimicrobial agent for orthodontic patients.

Punica granatum peel extracts: HPLC fractionation and LC MS analysis to quest compounds having activity against multidrug resistant bacteria.

Science.gov (United States)

Khan, Ilyas; Rahman, Hazir; Abd El-Salam, Nasser M; Tawab, Abdul; Hussain, Anwar; Khan, Taj Ali; Khan, Usman Ali; Qasim, Muhammad; Adnan, Muhammad; Azizullah, Azizullah; Murad, Waheed; Jalal, Abdullah; Muhammad, Noor; Ullah, Riaz

2017-05-03

Medicinal plants are rich source of traditional herbal medicine around the globe. Most of the plant's therapeutic properties are due to the presence of secondary bioactive compounds. The present study analyzed the High Pressure Liquid Chromatography (HPLC) fractions of Puncia granatum (peel) extracts (aqueous, chloroform, ethanol and hexane) against multidrug resistant bacterial pathogens (Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus). All the fractions having antibacterial activity was processed for bioactive compounds identification using LC MS/MS analysis. Among total HPLC fractions (n = 30), 4 HPLC fractions of P. granatum (peel) showed potential activity against MDR pathogens. Fraction 1 (F1) and fraction 4 (F4) collected from aqueous extract showed maximum activity against P. aeruginosa. Fraction 2 (F2) of hexane showed antibacterial activity against three pathogens, while ethanol F4 exhibited antibacterial activity against A. baumannii. The active fractions were processed for LC MS/MS analysis to identify bioactive compounds. Valoneic acid dilactone (aqueous F1 and F4), Hexoside (ethanol F4) and Coumaric acid (hexane F2) were identified as bioactive compounds in HPLC fractions. Puncia granatum peel extracts HPLC fractions exhibited potential inhibitory activity against MDR bacterial human pathogens. Several bioactive compounds were identified from the HPLC fractions. Further characterization of these compounds may be helpful to conclude it as therapeutic lead molecules against MDR pathogens.

Antiproliferative Activity of Flavonoids from Croton sphaerogynus Baill. (Euphorbiaceae

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Kátia Pereira dos Santos

2015-01-01

Full Text Available Croton sphaerogynus is a shrub from the Atlantic Rain Forest in southeastern Brazil. A lyophilized crude EtOH extract from leaves of C. sphaerogynus, obtained by maceration at room temperature (seven days, was suspended in methanol and partitioned with hexane. The purified MeOH phase was fractionated over Sephadex LH-20 yielding five fractions (F1–F5 containing flavonoids, as characterized by HPLC-DAD and HPLC-MS analyses. The antiproliferative activity of the crude EtOH extract, MeOH and hexane phases, and fractions F1–F5 was evaluated on in vitro cell lines NCI-H460 (nonsmall cell lung, MCF-7 (breast cancer, and U251 (glioma. The MeOH phase showed activity (mean log GI50 0.54 higher than the hexane phase and EtOH extract (mean log GI50 1.13 and 1.19, resp.. F1 exhibited activity against NCI-H460 (nonsmall cell lung (GI50 1.2 μg/mL, which could be accounted for the presence of flavonoids and/or diterpenes. F4 showed moderate activity (mean log GI50 1.05, while F5 showed weak activity (mean log GI50 1.36. It is suggested that the antiproliferative activity of the crude EtOH extract and MeOH phase is accounted for a synergistic combination of flavonoids and diterpenes.

Preparation of dual-sensitive graft copolymer hydrogel based on N ...

Indian Academy of Sciences (India)

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Organic solvent-soluble N-maleoyl-chitosan (NMCS) was synthesized by reaction of ... provement or modification of polymer materials through ... the mixture of hexane and toluene. ... reacted solution was cooled to room temperature and.

Enantiomeric separation and simulation studies of pheniramine, oxybutynin, cetirizine, and brinzolamide chiral drugs on amylose-based columns.

Science.gov (United States)

Ali, Imran; Al-Othman, Zeid A; Al-Warthan, Abdulrahman; Alam, Syed Dilshad; Farooqi, Javed A

2014-03-01

Solid phase extraction (SPE)-chiral separation of the important drugs pheniramine, oxybutynin, cetirizine, and brinzolamide was achieved on the C18 cartridge and AmyCoat (150 x 46 mm) and Chiralpak AD (25 cm x 0.46 cm id) chiral columns in human plasma. Pheniramine, oxybutynin, cetirizine, and brinzolamide were resolved using n-hexane-2-PrOH-DEA (85:15:0.1, v/v), n-hexane-2-PrOH-DEA (80:20:0.1, v/v), n-hexane-2-PrOH-DEA (70:30:0.2, v/v), and n-hexane-2-propanol (90:10, v/v) as mobile phases. The separation was carried out at 25 ± 1 ºC temperature with detection at 225 nm for cetirizine and oxybutynin and 220 nm for pheniramine and brinzolamide. The flow rates of the mobile phases were 0.5 mL min(-1). The retention factors of pheniramine, oxybutynin, cetirizine and brinzolamide were 3.25 and 4.34, 4.76 and 5.64, 6.10 and 6.60, and 1.64 and 2.01, respectively. The separation factors of these drugs were 1.33, 1.18, 1.09 and 1.20 while their resolutions factors were 1.09, 1.45, 1.63 and 1.25, and 1.15, respectively. The absolute configurations of the eluted enantiomers of the reported drugs were determined by simulation studies. It was observed that the order of enantiomers elution of the reported drugs was S-pheniramine > R-pheniramine; R-oxybutynin > S-oxybutynin; S-cetirizine > R-cetirizine; and S-brinzolamide > R-brinzolamide. The mechanism of separation was also determined at the supramolecular level by considering interactions and modeling results. The reported SPE-chiral high-performance liquid chromatography (HPLC) methods are suitable for the enantiomeric analyses of these drugs in any biological sample. In addition, simulation studies may be used to determine the absolute configuration of the first and second eluted enantiomers. © 2014 Wiley Periodicals, Inc.

77 FR 20334 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

Science.gov (United States)

2012-04-04

... exhaustive, but rather provides a guide for readers regarding entities likely to be affected by this action... digested with acid. The hydrolyzed metabolites are then extracted with a mixture of hexane and ether, and...

Preparation and characterization of monosubstituted porphyrins ...

Indian Academy of Sciences (India)

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phyrins in both synthetic chemistry and industrial process heavily. These shortcomings ... and environmental pro- blem, due to their wide production and use as explosives ... distilled under nitrogen atmosphere before use. Hexane was distilled ...

Antimicrobial activity of Arctium lappa constituents against microorganisms commonly found in endodontic infections.

Science.gov (United States)

Pereira, Juliana Vianna; Bergamo, Débora Cristina Baldoqui; Pereira, José Odair; França, Suzelei de Castro; Pietro, Rosemeire Cristina Linhares Rodrigues; Silva-Sousa, Yara T Corrêa

2005-01-01

This study evaluated in vitro the antimicrobial activity of rough extracts from leaves of Arctium lappa and their phases. The following microorganisms, commonly found in the oral cavity, specifically in endodontic infections, were used: Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis and Candida albicans. The agar-diffusion method allowed detection of the hexanic phase as an inhibitor of microbial growth. Bioautographic assays identified antimicrobial substances in the extract. The results showed the existence, in the rough hexanic phase and in its fractions, of constituents that have retention factors (Rf) in three distinct zones, thereby suggesting the presence of active constituents with chemical structures of different polarities that exhibited specificity against the target microorganisms. It may be concluded that the Arctium lappa constituents exhibited a great microbial inhibition potential against the tested endodontic pathogens.

Enzymatic production of ceramide from sphingomyelin

DEFF Research Database (Denmark)

Zhang, Long; Hellgren, Lars; Xu, Xuebing

2006-01-01

-saturated organic solvent) system. Among the screened phospholipase C, the Clostridium petfringens enzyme had the highest sphingomyetin conversion rate, with very small temperature dependence. Addition of ethanol to the system markedly enhanced the rate of ceramide formation, and a mixture of ethyl acetate: hexane...... (50:50) was the best organic solvent tested. Other factors such as (NH4)(2)SO4, MCI and CaCl, were also tested but excluded for further consideration. On the basis of the initial experiments, the reaction system was optimized using response surface methodology including five factors (enzyme amount...... systern evaluation and optimization, with the optimal conditions at 75 min reaction time, 3 U ml(-1) enzyme amount, 6% water amount, 1.8% ethanol arnount and 46% hexane in ethylacetate. (c) 2005 Elsevier B.V. All rights reserved....

Photoluminescence quenching of chemically functionalized porous silicon by a ruthenium cluster

Energy Technology Data Exchange (ETDEWEB)

Boukherroub, R.; Wayner, D.D.M. [Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario (Canada); Lockwood, D.J. [Institute for Microstructural Sciences, National Research Council of Canada, Ottawa, Ontario (Canada); Zargarian, D. [Chemistry Department, University of Montreal, C.P. 6128, succursale, Centre-ville, Montreal QC (Canada)

2003-05-01

This paper describes photoluminescence (PL) quenching of hydrogen-terminated and chemically derivatized porous silicon (PSi) nanostructures by a green ruthenium cluster (I). Chemisorption of freshly prepared PSi surfaces in a hexane solution of the Ru cluster for several days at room temperature led to a complete quenching of the PSi PL. The only visible PL was due to the original PL of the cluster. When the PSi surface functionalized with undecylenic acid was immersed in the same hexane solution of (I), the PSi PL was completely quenched and accompanied with a shift to a lower energy of the cluster PL. This shift was assigned to the formation of an ester linkage resulting from the nucleophilic attack of the PO anion of the cluster on the terminal acid functional group. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

Photoluminescence quenching of chemically functionalized porous silicon by a ruthenium cluster

Science.gov (United States)

Boukherroub, R.; Wayner, D. D. M.; Lockwood, D. J.; Zargarian, D.

2003-05-01

This paper describes photoluminescence (PL) quenching of hydrogen-terminated and chemically derivatized porous silicon (PSi) nanostructures by a green ruthenium cluster (I). Chemisorption of freshly prepared PSi surfaces in a hexane solution of the Ru cluster for several days at room temperature led to a complete quenching of the PSi PL. The only visible PL was due to the original PL of the cluster. When the PSi surface functionalized with undecylenic acid was immersed in the same hexane solution of (I), the PSi PL was completely quenched and accompanied with a shift to a lower energy of the cluster PL. This shift was assigned to the formation of an ester linkage resulting from the nucleophilic attack of the PO anion of the cluster on the terminal acid functional group.

Antimicrobial activity of the root, stem bark and seed extracts of moringa oleifera lam

International Nuclear Information System (INIS)

Manoti Ondicho, J.; Mutai, C.; Rukunga, G.; Oketch, P.; Bii, C.

2009-01-01

Organic extracts (Hexane, dichloromethane, ethyl acetate, methanol) and the aqueous extracts of Moringa oleifera Lam or horseradish (root, stem bark and seed) were tested against five bacterial strains using the disc diffusion method and against three fungal strains. The water extracts of the seed was active against a wide range of organisms tested. Hexane and ethyl acetate extracts of the stem bark exhibited moderate activity. Of the fifteen extracts screened, five (33.3 percent) showed activity against Staphylococcus aureus ATCC 25923 and against Trichophyton mentagrophytes while two were active against Microsporum gypseum. The minimal inhibitory concentration (MIC) values for the water extracts ranged from 6.25 to 50 mg/ml. The good activity observed on the water extract explains the success in traditional use of Moringa oleifera for the treatment of infectious diseases.(author)

Antimicrobial activity of the root, stem bark and seed extracts of moringa oleifera lam

Energy Technology Data Exchange (ETDEWEB)

Manoti Ondicho, J; Mutai, C; Rukunga, G; Oketch, P [Centre for Tradicional Medicine and Drug Research, Kenya Medical Research Institute, Nairobi (Kenya); Bii, C [Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi (Kenya)

2009-07-01

Organic extracts (Hexane, dichloromethane, ethyl acetate, methanol) and the aqueous extracts of Moringa oleifera Lam or horseradish (root, stem bark and seed) were tested against five bacterial strains using the disc diffusion method and against three fungal strains. The water extracts of the seed was active against a wide range of organisms tested. Hexane and ethyl acetate extracts of the stem bark exhibited moderate activity. Of the fifteen extracts screened, five (33.3 percent) showed activity against Staphylococcus aureus ATCC 25923 and against Trichophyton mentagrophytes while two were active against Microsporum gypseum. The minimal inhibitory concentration (MIC) values for the water extracts ranged from 6.25 to 50 mg/ml. The good activity observed on the water extract explains the success in traditional use of Moringa oleifera for the treatment of infectious diseases.(author)

[Determination of buprofezin, methamidophos, acephate, and triazophos residues in Chinese tea samples by gas chromatography].

Science.gov (United States)

Zhang, Shuiba; Yi, Jun; Ye, Jianglei; Zheng, Wenhui; Cai, Xueqin; Gong, Zhenbin

2004-03-01

A method has been developed for the simultaneous determination of buprofezin, methamidophos, acephate and triazophos residues in Chinese tea samples. The pesticide residues were extracted from tea samples with a mixture of ethyl acetate and n-hexane (50:50, v/v) at 45 degrees C. The extracts were subsequently treated with a column packed with 40 mg of active carbon by gradient elution with ethyl acetate and n-hexane. Buprofenzin and the three organophosphorus pesticides were analyzed by gas chromatography using a DB-210 capillary column and a nitrogen-phosphorus detector. The recoveries for spiked standards were 73.4%-96.9%. The relative standard deviations were all within 4.63%. The limits of quantitation (3sigma) in the tea samples were about 7.0-12.0 microg/kg.

Modulation of the norfloxacin resistance in Staphylococcus aureus by Cordia verbenaceae DC.

Science.gov (United States)

Matias, Edinardo F F; Santos, Karla K A; Falcão-Silva, Vivyanne S; Siqueira-Junior, Jose P; Costa, Jose G M; Coutinho, Henrique D M

2013-01-01

Several chemical compounds isolated from natural sources have antibacterial activity and some enhance the antibacterial activity of antibiotics reversing the natural resistance of bacteria to certain antibiotics. In this study, the hexane and methanol extract of Cordia verbenaceae were assessed for antibacterial activity alone and combinated with norfloxacin against the Staphylococcus aureus strain SA1199B. The minimum inhibitory concentration (MIC) of extracts was assayed using microdilution assay and the modulatory activity was evaluated using plate diffusion assay. The MIC observed varied between 256 to >1024 μg/ml. However, the antibiotic activity of norfloxacin was enhanced in the presence of subinhibitory concentrations of hexane extract of C. verbenaceae (HECV). INTERPRETATIONS & CONCLUSIONS: Our results indicate that Cordia verbenaceae DC. can be a source of plant derived products with antibiotic modifying activity.