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Liquid chromatography-mass spectrometry (LC-MS) in atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) modes were studied for a multi-component plasma and urine quantification of 5 antihyperglycemic agents (metformin, pioglitazone, gliclazide, glibenclamide, and glimperide). The separation of the compounds was achieved using Chromolith Performance RP-18e column (100 × 4.6 mm), with gradient mobile phase composition of acetonitrile −0.1% formic acid. MS parameters for APCI and ESI were optimized individually and were operated in positive mode. The detection limits for the metformin, pioglitazone, glibenclamide, and glimepiride were determined to be 6.84, 6.22, 13.03, and 44.38 ng mL−1 using LC-ESI-MS; and for LC-APCI-MS, it was determined to be 48.39, 8.02, 17.02, and 144.55 ng mL−1, respectively. Gliclazide was the only exception as it exhibited a lower limit of detection (LOD) using APCI than ESI which was found to be 5.61 and 23.43 ng mL−1, respectively. The method was vali...

The extracted oils from four apple seed varieties (Royal Gala, Red Delicious, Pyrus Malus and Golden Delicious) from Pakistan were investigated for their fatty acid profiles and lipid biactives by GC-MS. The oil contents in the seeds of the apple varieties ranged from 26.8-28.7%. The results revealed that linoleic acid (40.5-49.6%) was the main fatty acid in the Royal Gala, Red Delicious and Pyrus Malus seeds, and oleic acid (38.7-45.5%) was the main fatty acid in the Golden Delicious seeds. Palmitic acid (6.1-7.4%) and stearic acid (2.0-3.1%) were the dominant saturated fatty acids, besides the small amount of palmitoleic, heptadecanoic, linolenic, archidic, eicosanoic, and behenicacids. Sterols, tocopherols, hydrocarbons and some other minor components were also identified from the unsaponifiable lipid fraction. The variation among the results of both fatty acids and lipid bioactives for the four different varieties was assessed by principal component analysis, discriminant analysis and cluster analyses. The results conclude that both oil fractions could be applied as a useful tool to discriminate among the apple seed varieties.Se ha estudiado el perfil de ácidos grasos y lípidos biactivos mediante GC-MS del aceite extraído de semillas de cuatro variedades de manzanas de Pakistán (Royal Gala, Red Delicious, Pyrus Malus y Golden Delicious). El contenido de aceite en las semillas de las variedades de manzanas estudiadas oscilaron desde 26,8 hasta 28,7%. Los resultados mostraron que el ácido linoleico (40.5-49.6%) fue el principal ácido graso de las semillas de las variedades Royal Gala, Red Delicious y Pyrus Malus, y el ácido oleico (38,7-45,5%) fue el principal ácido graso de Golden Delicious. Los ácidos palmítico (6.1-7.4%) y esteárico (2,0-3,1%) fueron los ácidos grasos saturados predominantes, las semillas contenían también pequeñas cantidades de palmitoleico, heptadecanoico, linolénico, araquídico, eicosanoico, y behénico. Esteroles, tocoferoles, hidrocarburos, y otros componentes menores también fueron identificados a partir de la fracción insaponificable. La variación de los resultados de ambos, ácidos grasos y lípidos bioactivos, de cuatro variedades diferentes se evaluó mediante análisis de componentes principales, análisis discriminante y análisis de cluster. Los resultados concluyen que las dos fracciones lipídicas de semillas de manzanas podrían aplicarse como una herramienta útil para distinguir variedades.

The essential oil from air dried buds and roots of Calligonum polygonoides Linn., has been extracted from dry steam distillation and analysed for chemical composition by gas chromatography-mass spectrometry. In total, 27 and 10 compounds were analysed qualitatively and quantitatively, accounting for 68.42% and 82.12% total contents of the essential oils of buds and roots, respectively. It contains a complex mixture of terpenoids, hydrocarbons, phenolic compounds, acid derivatives and ketones. The main component of essential oil was ethyl homovanillate (11.79%) in buds and drimenol (29.42%) in roots.

Ber is a tropical fruit which grows from the tree species, Ziziphus mauritiana Lamk. The pericarp of this fruit is consumed either fresh or dried while its seeds are usually discarded as waste. The present study was undertaken to evaluate the antioxidant activity and phenolic content of the fruit, and to evaluate if any potential value-added phytochemicals can be extracted from seed waste. The edible portion of the fruit was extracted with 60% aqueous methanol by sonication and then assayed for total phenolic content, antioxidant activity, and individual phenolic compounds by HPLC-DAD. The seed oil extracted with n-hexane was assayed for fatty acid composition, sterols, and tocopherols content by GC-MS. The total phenolic content of the fresh fruit was 1.28 g/100 g gallic acid equivalent, with an antioxidant activity of 50.9 μmol/100 g quercetin equivalent by Folin-Ciocalteu and DPPH assays respectively. Hydroxybenzoic acid, vanillin, ortho- and para-coumaric acid, epicatechin, quercetin, and naringenin were tentatively identifi ed by matching retention time and UV spectra with those of commercial reference standards. GC-MS analysis of the TMS derivative of fruit extract showed the presence of following compounds: propanoic, hexanoic, heptanoic, octanoic, nonanoic, decanoic, dodecanoic, n-pentadecanoic, hexadecanoic, benzoic, and trihydroxybenzoic acids. In addition, D-fructose, galactofuranoside, gluconic acid, and β-sitosterol were also detected. In seed oil of ber, the fatty acids such as, hexanoic, octanoic, 7-octadecenoic, 9,12-octadecendoic, eicosanoic, 11-eicosenoic, and docosanoic acid with 7-octadecenoic acid, were found to make up 55% of total fatty acids. Squalene, γ-tocopherol and stigmasterol were identifi ed as minor constituents in the unsaponifi able fraction of seed oil. Current study shows that ber fruit is a good source of healthy phytochemicals. Original Paper Section: Food Quality and Functionality

3 Abstract: The aim of this study was to determine the mineral contents of jamun fruit (Eugenia jambolana) products namely jam, squash, ready-to-drink juice, pulp powder and seed powder. The products were made and stored for 24 months at various storage conditions in different packaging material since it was an essential part of doctoral study carried out in 2007-2009. About 09 mineral elements such as Cr, Cu, Mn, Zn, Fe, Mg, Ca, Na and K in all jamun products were detected through atomic absorption spectrophotometer. The minimum and maximum macronutrients of Jamun products were determined as mg/kg. Two varieties of Jamun namely improved-V1 and indigenous-V2 were used. From the results of this study it could be concluded that there is a significant difference between the products as well between the cultivars however, VI is comparatively better than V2 in containing minerals.

This study was aimed to assess the adsorption and leaching potential of imidacloprid pesticide in column and field soil. To visibly understand these actions and factors affecting them, the experiments were carried out under laboratory and field conditions. Adsorption study was divided into kinetic and equilibrium sections. The evaluation of kinetic data was done through pseudo first and second order models. It was found that kinetic adsorption of imidacloprid on soil followed pseudo second order with rate constant value of 4.333 mg/g/h. Langmuir and Freundlich isotherms were used to explain equilibrium adsorption, from these isotherms it was evaluated that Freundlich isotherm was obeyed well with adsorption capacity of 2.190 - 4.573 mol/g. Leaching study was performed in laboratory using column made of poly-vinyl chloride having 30 cm length. Known amount of imidacloprid pesticide was applied to column left for adsorption and then eluted with 500 mL water in five equal portions. These water portions and soil of column which was divided into three sections were analyzed by HPLC. The result revealed that the concentration of imidacloprid was decreased from 0.481 ppm in first portion of water to 0.327 ppm in last portion of water while 0.783 ppm in first section of column soil to 0.038 ppm in last section of column soil. In field the leaching power of imidacloprid was observed up to 60 cm depth, its concentration decreased with soil depth. It was 3.311 ppm in first portion of soil and 0.357 ppm in last portion of soil. The leaching potential of imidacloprid pesticide up to 60 cm soil depth was due to less organic matter, sandy texture, alkaline pH, and low cation exchange capacity.

A rapid, simple and reproducible single bounce attenuated total reflectance (SB-ATR) Fourier transform infrared (FTIR) spectroscopic method was developed for determination of the n − 6, n − 3 and ratio of n − 6: n − 3 polyunsaturated fatty acids (PUFAs) in poultry feed lipids using partial least squares (PLS) regression. Data for n − 6, n − 3 and ratio of n − 6: n − 3 was acquired by gas chromatography (GC) and used as a standard values for FTIR calibration. The best regression results were achieved using first derivatives of the 1475–650 cm −1 spectral region for n − 6, n − 3 and ratio of n − 6: n − 3 with high regression coefficients ( R 2 ) of 0.999, 0.994 and 0.998, respectively and low RMSEP values of 1, 0.06 and 0.83, respectively. The results of the present study revealed that FTIR could be used for rapid and accurate determination of n − 6, n − 3 and ratio of n − 6: n − 3 PUFAs present in poultry feed lipids.

A bulk liquid membrane (BLM) experiment was carried out to check the Cu(II) transport efficiency of p-morpholinomethylcalix[4]arene (1) which was used as carrier. Liquid/liquid extraction experiments were also carried out to check the extraction and decomplexation efficiency of carrier 1. It has been observed that the maximum amount of Cu(II) was transported at pH = 12. The mass transfer of Cu(II) was analyzed on the basis of kinetic laws of two consecutive irreversible first order reactions. Thus, the kinetic parameters studied for the transport of Cu(II) were k1, k2, . BLM study revealed that Cu(II) transport increase with increase in concentration of carrier 1 from 1 × 10−5 to 1 × 10−4 M, rise in temperature from 298 to 308 K and at high stirring speed from 90 to 800 rpm. The effect of binary solvents on Cu(II) transport through BLM has also been studied. The values of k1, k2, decrease in the order of dichloromethane-hexane > dichloromethane-diethylether > dichloromethane > dichloromethane-ethylacetate...

In the present study, the quality of frying oil, as affected by commercial pan fish frying, was investigated. The quality of fresh frying oil, null replenishment (NR) oil, and discarded frying oil were evaluated by drawing out the oil samples from the fryer at the initial stage, just before the addition of new frying oil for level make-up and used oil of the last frying cycle, respectively. The parameters used to assess the quality were the fatty acid composition including trans fatty acid (TFA), free fatty acid, and peroxide values of frying oil. Gas chromatography-mass spectroscopy (GC-MS) was used to examine fatty acids profiles of the frying oils. Trans fatty acid in fresh oils varied from 2.5%–3.8% (except oil-6, which contained 13%), whereas NR oils and discarded oils contained 5.6%–14.8% and 7.3%–20.8% trans fatty acids, correspondingly. Free fatty acid in fresh, NR, and discarded oils were 0.12%–0.24%, 0.22%–1.74%, and 0.80%–3.39%, respectively. Peroxide value in fresh, NR, and discarded oils were...

This study was carried out to determine the proximate composition, fatty acid profile and biometric data for farm fish species Labeo rohita , Cirrhinus mrigala , Catla catla raised under identical conditions. The analysed fish species were found as source of high polyunsaturated fatty acids with low fat high protein. Fat content of the fish fillets was in range 2.57–3.11 g/100 g. Whereas fat content for feed was 14.90 g/100 g. The protein level for the three fish ranged from 20.00–23.57 g/100 g and in feed it was estimated in the range of 67.70 g/100 g. The palmitic acid and stearic acid were the main saturated fatty acids (SFA), oleic acid was the predominant MUFA while the docosahexanoic acid and eicopentanoic acid were the major PUFA. The percentage of DHA exceeded that of EPA in all fish species analysed. The n−3/n−6 ratio ranged from 1.69–1.91. PUFA/SFA ratio was much higher in L. rohita (1.40) due to abundance of n−3 PUFA, particularly DHA.

The present article demonstrates the synthesis of p-tetraaminocalix[4]arene- and p-tetrathioureacalix[4]arene-based resins (4 and 5). The resins (4 and 5) were characterized by using different analytical techniques such as FT-IR and elemental analysis. In addition, their comparative fluoride sorption study was conducted and it was observed that 5 is highly efficient for the removal of fluoride from aqueous media at a wide range of pH as compared to 4. Consequently, on the basis of kinetic and thermodynamic studies, the pseudo first-order, pseudo second-order, entropy, enthalpy, and Gibbs free energy of fluoride sorption onto resin 5 were calculated. The experimental data were also evaluated by equations of isotherms used, i.e., Freundlich, Langmuir, and Dubinin–Radushkevich. The observations reveal that the sorption is favorable and confer the physiosorption interaction between resin 5 and fluoride.

The present study describes the sorption of fluoride on a potential and newly synthesized p-tetraaminocalix[4]arene based resin (p-TAC4 resin). The p-TAC4 resin was synthesized via immobilization of p-tetranitrocalix[4]arene (p-TNC4) onto the Merrifield resin followed by catalytic reduction with SnCl2/EtOH/HCl. The p-TNC4 and p-TAC4 resins were characterized using FT-IR, elemental analysis, and scanning electron microscopy (SEM). Fluoride removal capability from the aqueous media of the p-TAC4 resin has been evaluated through batch sorption study. The effect of pH, sorbate concentration, sorbent dosage, and contact time on fluoride removal was evaluated. The Langmuir (L), Freundlich (F), and Dubinin–Radushkevich (D-R) isotherms revealed that the fluoride on p-TAC4 resin follows physiosorption mechanism. All the results support and emphasize that the p-TAC4 resin is an effective sorbent for the removal of fluoride from the aqueous environment at a wide range of pH. The study may confer its impact on human ...

Summary A rapid and reliable analytical procedure has been developed for the separation and analysis of dioxouranium, thorium, gold, and mercury by micellar electrokinetic chromatography (MEKC) using bis(acetylacetone)ethylenediamine (H2AA2en) as complexing reagent. Under the optimized conditions (64 mm borate buffer containing 12.25 mm SDS and 13% acetonitrile, pH 8.0, 25 kV, 311 nm as detection wavelength) the ions were separated within 5.0 min. Linear dynamic ranges were 1–5, 8–42, 10–50, and 2–40 μg mL−1, respectively, for gold, mercury, thorium, and uranium and the respective detection limits were 0.66, 3.33, 1.6, and 3.3 μg mL−1. The applicability of method has been evaluated by application to uranium and thorium from ore samples.

A market based survey was carried out to evaluate the level of 26 pesticides in some commonly used fruits in Hyderabad region, Pakistan. Gas chromatography coupled with micro electron capture detector was used to assess the levels of pesticide residues. Gas chromatography-mass spectrometry (GC-MS) was also applied for the confirmation of results. Out of total 131 analyzed samples, 53 (40%) were found contaminated with pesticide residues while only 3 (2%) samples were exceeded the MRLs of some pesticides. Chlorpyrifos and dieldrin were detected in almost all analyzed samples. Residues of chlorpyrifos (1256 µg/kg) and endosulfan sulfate (1236 µg/kg) were found higher in orange and apple samples, respectively. The findings of this study provided important data about contamination of pesticide residue in some fruits sold in Hyderabad, Pakistan, and recommended that monitoring studies should be expanded to other fruits grown in different agro climatic regions, which may serve as basis for future policy about the standards and quality control of pesticides.

Chlorogenic acid (CGA) is a phenolic antioxidant compound with medicinal activities especially as promising precursor for the development of medicines that can resist AIDS virus HIV. This study explores the micelle-mediated extraction of CGA from Morus laevigata W. leaves which is superior to conventional methods involving organic or organo-aqueous solvents. In this new method, sodium dodecylsulfate (SDS) surfactant solution was used as efficient extraction medium in combination with microwave irradiation to shorten the extraction time. Crude extract of CGA with SDS solution as solvent was purified by ethyl acetate at high ionic strength followed by washing with hexane: chloroform mixture. Quantitation of CGA was carried out on liquid chromatography with diode array detection. The optimum extraction of 2152 mg/100 g CGA from freeze dried M. laevigata W. leaves was achieved using 0.1 M of SDS at pH 1.0 with extraction time of 10 s and microwave power of 50 W. Best results were observed when 0.2 g of plant material was extracted with 20 mL of solvent. CGA obtained from M. laevigata W. leaves was compared with pure standard of CGA, and found to be 95.9% pure.

The purpose of this study was to determine the total trans fat content from the Fourier transform infrared (FT-IR) spectra of neat fats extracted from cereal-based foods using a single-bounce horizontal attenuated total reflectance (SB-HATR) sampling accessory. Partial least squares (PLS) regression was employed for the development of calibration models. A trans fat calibration curve was prepared by adding trielaidine gravimetrically to trans free canola oil. Regression of the FT-IR/PLS-predicted trans contents was 0.999 with a root-mean-square error of calibration (RMSEC) and root-mean-square error of prediction (RMSEP) 0.07% and 0.07%, respectively. Amongst the samples examined, the fat content was in the range of 8.2–27.2%, whilst most samples contained more than 10% trans fat; the highest trans fat content was 16.3%. The FT-IR results were comparable with gas chromatography (GC).

In this study effectiveness of 5,11,17,23 tetrakis[(propylthio)methyl]-25,26,27,28-tetrahydroxycalix[4]arene ( 1 ) towards Hg(II) across bulk liquid membrane has been examined. The effect of the fundamental parameters influencing the transport process, e.g. carrier concentration, type of solvent used, effect of temperature and time dependency of the process have been investigated. The mass transfer of Hg(II) was analyzed on the basis of kinetic laws of two consecutive irreversible first order reactions. Thus, the kinetic parameters ( k 1 , k 2 , R m max , t max , J d max , J a max ) for the transport of Hg(II) were studied. The activation energy values for the extraction and re-extraction were found as 19.59 and 27.57 kJ mol − 1 , respectively. These values demonstrate that the process is diffusionally controlled by Hg(II). Observations show that the membrane entrance and exit rate constants ( k 1 , k 2 ) increase with increasing stirring speed, carrier concentration and temperature. The effect of solvent on k 1 and k 2 was found to be in the order of CH 2 Cl 2 > CHCl 3 > CCl 4 . The effectiveness and reproducibility of Hg(II) transport has proved that 1 is an efficient carrier of Hg(II) in BLM process.

Charles University in Prague, Faculty of Science, Department of Analytical Chemistry, UNESCO Laboratory of EnvironmentalElectrochemistry, Hlavova 2030, 12843 Prague 2, Czech Republic*e-mail: barek@natur.cuni.czReceived: January 20, 2010Accepted: February 15, 2010AbstractA new simple, fast and sensitive differential pulse voltammetric method was developed for the determination ofdifferent aliphatic phthalates. Dibutyl phthalate, diethyl phthalate, didecyl phthalate, and diallyl phthalate can bedetermined in 0.1 M tetramethylammonium bromide in methanol using a hanging mercury drop minielectrode and ameniscus modified silver solid amalgam electrode. Optimum conditions were found including concentration andcomposition of supporting electrolyte and solvent, scan rate, pulse amplitude, pulse width, etc. Linear calibrationcurves were obtained for 10

Complex formation between copper (II) sulfate and morin (3,5,7,2′,4′-pentahydroxyflavone) have been studied in methanol. Structure of the complex was determined through various analytical techniques including UV–vis, IR, 1 H NMR, thermal, gravimetric and elemental analyses. The stoichiometric ratio for the reaction between the flavonoid and the metal ion in methanol has been determined by Job’s method and elemental analysis for metal content of complex by titration with EDTA, which confirm that morin forms a 1:1 metal:ligand complex. 1 H NMR study reveals that, 3OH and 4CO groups of morin take part in complexation with a copper ion. Individual stress was given to the site of central ion and composition of the complex. Antioxidant activity of the complex was evaluated by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method, which showed that the antioxidant activity of complexed morin has higher value as compared to the free morin. Moreover, it was observed that the metal complex is sufficiently stable as well as the data indicates the spontaneous formation of complex (−Δ G ) that is exothermic in nature (−Δ H ) and entropically unfavourable (−Δ S ).

Eight species of freshwater fish from the Indus River were analyzed for their proximate composition and fatty acid (FA) profile. Differences were observed (P < 0.05) for moisture (59.95–79.45%), ash (0.05–4.95%), crude protein (17–20.09%) and lipid (0.85–18.32%) contents. The changes in FA profiles of fish species were significant (P < 0.05). The monounsaturated (MUFA) fatty acid content (24.55–48.35 g/100 g) was higher than the saturated fatty acid (SFA) (25.04–41.02 g/100 g) and polyunsaturated fatty acid (PUFA) (15.72–35.34 g/100g). The predominant PUFAs were eicosapentaenoic acid (C20:5 n-3) and docosahexaenoic acid (C22:6 n-3). All of the fish species had n-3/n-6 within the recommended values (1–4), which confirms he importance of River Indus fish as a significant dietary source of n-3 PUFA.

Ethyl chloroformate was used as a derivatizing reagent to develop a simple and sensitive gas chromatographic procedure for the determination of tranexamic acid. Analysis was performed on an HP-5 column (30 m × 0.32 mm i.d.) coupled with mass spectrometric detection. Linear response was obtained from 60 to 500 pg with a limit of detection of 20 pg tranexamic acid injected onto the column. Aminocaproic acid was used as an internal standard. Tranexamic acid was determined in pharmaceutical preparations and blood samples after therapy with the drug. Appoximately 2.0 μg mL−1 was found in blood samples. Relative standard deviation for analysis was within 0.1–0.4% (n = 3). Recovery of tranexamic acid added to deprotenized serum was 99.6% with an RSD of 1.2–1.6% (n = 3). Pharmaceutical additives and amino acids, if also present, did not affect the determination.

Fluoride in drinking water above permissible level is responsible for human being affected by skeletal fluorosis. In this study, Amberlite XAD-4™ has been modified by introducing amino group onto the aromatic ring for its application in fluoride remediation. Characterization of the modified resin was made by, FT-IR and elemental analysis (CHNS) techniques. The pH 9 was optimum value for quantitative sorption of fluoride in both batch and column experiments. The desorption of fluoride was achieved by using 10% HCl. The batch and column sorption studies of fluoride with modified resin were carried out to evaluate sorption isotherms too. Thus equation isotherms such as Langmuir, Freundlich, and Dubinin–Radushkevich (D–R) were successfully used to model the experimental data. The sorption capacity of modified Amberlite XAD-4 resin was found as 5.04 × 10 −3 mol g −1 . From the D–R isotherm parameters, it has been evaluated that the uptake of fluoride by modified resin occurs through ion exchange adsorption mechanism. The study will contribute toward the removal of fluoride from the aqueous environment as well as in the field of analytical and environmental chemistry.

A differential pulse voltammetric (DPV) method was developed for the determination of 4-nitrophenol (4-NP) at a newly developed silver amalgam paste electrode (AgA-PE) in Britton–Robinson buffer pH 3.0. The electrode is based on a disposable plastic pipette tip filled with paste amalgam based on a mixture of mercury and fine silver powder (9 : 1, w/w). The experimental parameters, such as pH of Britton–Robinson buffer and activation and regeneration potential of the electrode surface were optimized. The reduction peak current dependences were linear for the concentration of 4-NP from 0.2 to 100 μM. The method showed reproducible results with RSD (n=45) of 1.7%. The limit of determination (LOD) was 0.3 μM. The method was successfully applied for the direct determination of 4-NP in drinking water.

An efficient voltammetric method was developed for the determination of maleic acid at a silver amalgam paste electrode (AgA-PE) in Britton–Robinson buffer pH 2.0. The experimental parameters, such as pH of Britton–Robinson buffer, type of the supporting electrolyte and activation of the electrode surface were optimized. Under the optimal conditions, a linear response was observed over the 2×10−6–1×10−4 mol L−1 maleic acid concentration range, determination limit being 5×10−7 mol L−1. A highly stable response, with a relative standard deviation (RSD) of 1.6% for 45 repetitive measurements of 1×10−4 mol L−1 maleic acid showed that there was no apparent surface passivation indicating the suitability of the method. The method was successfully applied for direct determination of maleic acid in drinking and river water.

The chemical composition and antioxidant and antimicrobial activities of the hydro-distilled essential oils from the fruit of sweet fennel (Foeniculum vulgare Miller) were investigated at three stages of maturity (immature, intermediate, and mature). Maximum essential oil content (3.5%) was observed in the mature, and the minimum oil content (2.8%) was observed in immature fruit. GC–MS analysis of the fennel essential oils from the plants revealed the presence of trans-anethole (65.2%, 69.7%, 72.6 %); fenchone (8.8%, 10.0%, 11.0%); estragole (6.9%, 6.9%, 7.2 %); and limonene (7.8%, 4.7%, 3.5 %) as the main components at immature, intermediate, and mature stages, respectively. Both the essential oils and trans-anethole, the principal constituent, exhibited appreciable antioxidant and antimicrobial activities as assessed by 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging ability, bleaching β-carotene in linoleic acid system, inhibition of linoleic acid oxidation, disc diffusion, and microdilution brot...

The adsorption of methyl parathion from aqueous solutions by the low-cost and abundant adsorbent mango kernel was studied in a batch adsorption system. The adsorption was studied as a function of pH, contact time, initial pesticide concentration, adsorbent dose, and temperature. A maximum adsorption of 98% ± 1% was achieved. Physicochemical characterization of the adsorbent was carried out by EDXRF, BET, and CHNS analysis. Freundlich, Langmuir, and Dubinin-Radushkevich isotherms were employed to evaluate the adsorption capacity of the adsorbent. Lagergren, Morris-Weber, and Reichenberg equations were employed to study the kinetics of the adsorption process. Thermodynamic parameters Δ H, Δ S, and Δ G were computed. The developed adsorption method was applied to real environmental samples.

The amount of trans fatty acids (TFA) in fourteen industrially hydrogenated and deodorized oils was determined. To achieve better sensitivity 200 μm KCl cell was used in transmission Fourier transform infrared (FT-IR) spectroscopy. The results of transmission FT-IR spectroscopy were evaluated by gas chromatography (GC) with flame ionization detector (FID), and found to be comparable. All analyzed cooking oil samples had a lower trans content of 0.4–1.8%. Trans fatty acid contents of partially hydrogenated oil samples were relatively higher as comparable to those of the cooking oils. Among the samples examined, the highest level was found to be at 26.5% and 25.7% by the GC–FID and FT-IR spectroscopy, respectively. Due to harmful effects, high amounts of trans fatty acids in partially hydrogenated oils is an alarming issue for the consumer’s health and quality control authorities.

The present study describes the Pb(2+) sorption potential of newly synthesized tetraester calix[4]arene (TC4) based resin from aqueous media. The TC4 resin was synthesized through diazotization reaction of TC4 with Amberlite XAD-4 in the presence of sodium nitrite in acidic medium. The TC4 resin was characterized by using different analytical techniques such as FT-IR, elemental analysis and scanning electron microscopy (SEM). The Pb(2+) removal ability of the resin from the aqueous environment has been evaluated by both batch adsorption as well as column studies. The experiments have been conducted involving the determination of effect of pH, adsorbate concentration, adsorbent dosage, contact time and temperature. Moreover, on the basis of kinetic studies, the pseudo-first-order and pseudo-second-order adsorption kinetics were calculated. The thermodynamic parameters of lead adsorption were also calculated. Equation isotherms such as Langmuir (L), Freundlich (F), and Dubinin-Radushkevich (D-R) were successfully used to model the experimental data. From the D-R isotherm parameters, it was considered that the uptake of Pb(2+) by TC4 resin is ion exchange mechanism. From the results it has been found that the TC4 resin is a versatile adsorbent for the removal of Pb(2+) from the aqueous environment. The study also confers its impact on human health, reinstate of polluted sites and other fields of material science.

Sensitive cathodic stripping voltammetric methods have been developed for two quinolone antibacterial drugs, pipemidic acid (PIP) and ofloxacin (OFL) using hanging mercury drop electrode as working electrode vs. Ag/AgCl reference electrode. The methods were developed for the determination of drugs individually as well as simultaneously. 0.1 M and 0.01 M hydrochloric acid was used as medium for PIP and OFL, respectively, 0.1 M potassium chloride was used as base electrolyte. Reduction waves were observed for PIP within −700 mV to −800 mV and for OFL within −1100 mV to −1200 mV. Linear calibration ranges for PIP and OFL were observed within 10–100 μg ml−1 with detection limits of 50 ng ml−1 and 1 μg ml−1, respectively. Relative standard deviations (RSD) for the analysis of 10 gµg ml−1 of PIP and OFL (n = 6) were 0.5% and 1.4%, respectively. The presence of glucose, lactose, sorbitol, gum arabic, starch, magnesium stearate, methylparaben and propylparaben did not affect the determinations of both PIP and OFL. The methods were used for the analysis of pharmaceutical preparations and the results indicated relative deviation of 0.5–5.5% from labeled values with RSD within 0.49–2.5%. PIP and OFL could also be determined simultaneously, and were determined from spiked human urine.

The present study was undertaken to evaluate the breed influence on milk fatty acid (FA) composition, particularly on the concentration of conjugated linoleic acid (CLA) from two different indigenous breeds of goats (Pateri and Kamori; n = 30 for each breed) and ewes (Kachi and Kooka; n = 25 for each) from Sindh, Pakistan. All animals were managed together and received the same diet. Statistical significant differences ( P cis -9, trans -11 CLA concentration from Kamori goats and Kooka ewes were [17–28%] higher when compared to Pateri goats and Kachi ewes, with mean values of 0.48 g/100 g for goat breeds and 0.82 g/100 g for ewes. The greatest differences ( P P > 0.05) among goat and ewe breads, ranging from 2.45 to 3.60 for goats and 2.48 to 3.27 g/100 g for ewes. The present study reveals that the breed has a pronounced effect on FA composition of goat and ewes milk fat, and in the future genetic selection plans along with improved nutrition program of goats and ewes may result in optimum levels of various fatty acids in milk.

The sorption efficiency of chickpea husk of black gram variety (BGH), for the removal of organophosphorous pesticides (OPPs), i.e. triazophos (TAP) and methyl parathion (MP) from aqueous media has been investigated. Optimization of operating sorption parameters, i.e. particle size, sorbent dose, agitation time, pH, initial concentration of sorbates, and temperature has been studied. The sorption data fitted well to Freundlich, Langmuir and Dubinin–Radushkevich (D–R) sorption isotherms. The maximum sorption capacities of BGH for TAP and MP were calculated to be 3.5 ± 0.45 and 10.6 ± 0.83 mmol g −1 by Freundlich, 0.0077 ± 0.021 and 0.025 ± 0.0094 mmol g −1 by Langmuir and 0.48 ± 0.037 and 0.15 ± 0.077 mmol g −1 by D–R isotherms respectively, employing 0.2 g of sorbent, at pH 6, 90 min agitation time and at 303 K. Application of first order Lagergren and Morris–Weber equations to the kinetic data yielded correlation coefficients, close to unity and showed partial intra-particle diffusion. The negative values of thermodynamic parameters, i.e. Δ H (kJ mol −1 ), Δ S (J mol −1 K −1 ) and Δ G (kJ mol −1 ) indicate the exothermic and spontaneous nature of the sorption process. The sorbed pesticides were recovered by sonication with methanol, making the regeneration and reutilization of the sorbents promising. The investigated sorbent exhibited potential applications in water decontamination, treatments of industrial and agricultural waste waters and thus productively demonstrated viable use of agricultural waste material.

Quercetin (3,3′,4′,5,7-pentahydroxyflavone) one of the most abundant dietary flavonoids, has been investigated in the presence of Cu(II) in methanol. The spectroscopic studies (UV–vis, 1H NMR and IR) were useful to assess the relevant interaction of Quercetin with Cu(II) ions, the chelation sites and dependence of the complex structure from the metal/ligand ratio. A 1:2 (L:M) complex was indicated by Job's method of continuous variation, which was applied to ascertain the stoichiometric composition of the complex. The antioxidant activities of the compounds were evaluated by using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. The complexed flavonoid was much more effective free radical scavengers than the free flavonoids.

Owing to increased safety concerns about synthetic antioxidants, exploitation of safer antioxidants based on natural origin is the focus of research nowadays. Cumin is a common spice and is used as a routine supportive cooking agent. Extracts of cumin were prepared in methanol, ethanol, dichloromethane and hexane by employing Soxhlet extraction apparatus. Determination of the total phenolic content, chelating activity, reducing power and free radical scavenging activity were taken as parameters for the assessment of antioxidant properties. The findings of this study suggest cumin to be a potent source of antioxidants. Results from the different parameters were in agreement with one another.

This article describes a novel synthesis of cobalt and quercetin·2H 2 O complex in methanol, characterized by using elemental analysis, UV–visible, 1 H NMR, TGA, DSC and IR spectrometric techniques. The formation of complex is deduced from the UV–visible spectra which shows that the successive formation of cobalt–quercetin complex occurs in a ratio of 2:1 (metal/ligand) stoichiometrically. The antioxidant activity of the complex was evaluated by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. In this work, we have shown that the metal complexed flavonoids are much more effective free radical scavengers than the free flavonoids.

The present study was undertaken to assess the intramuscular fatty acid composition of different muscles taken from male Pateri (n=15) goats, reared on naturally grown grasses, leaves and pods of Acacia nilotica and crushed cereal, under traditional way of feeding. Goats were slaughtered with an average weight of 68±7kg and age 12±1 month. The samples were taken from longissimus dorsi region (between the 12th and 13th rib) and distal region of semitendinosus muscle. Results of total fat content and fatty acids composition does not show significant (P>0.05) variation among muscles investigated. The fatty acid composition of muscles studied were primarily composed of oleic (31.50-33.38%), followed by palmitic acid (19.84-22.05%) and stearic acid (22.25-24.91%) respectively. Muscle tissue in general contained an average 51.13% of saturated fatty acids and 48.87% of unsaturated fatty acids. The mean conjugated linoleic acid was found 0.41%, 0.43% and 0.47% in ribeye and loin portion of longissimus dorsi muscle and distal region of semitendinosus muscle, respectively.

The selective behavior of calix[n]arene ester derivatives in two-phase extraction systems using polarographic technique has been investigated. Calix[4]arene tetraester derivative shows remarkable Na+ over Pb2+ selectivity; whereas calix[6]arene hexaester derivative shows Pb2+ over Na+ selectivity. The interference of some selected cations (Na+, K+, Cu2+ and Mg2+) were also examined and no significant effect on the selectivity behavior as well as extraction ability of these ionophores was found except Na+. The study reveals for the first time that the calix[6]arene hexaester derivative is highly Pb2+ selective ionophore and can be employed in the field of sensor as well as separation science and technology. The work also highlights the usefulness of polarographic technique in trace metal determination.

The objective of this work was to study changes in the fatty acid (FA) profile of ruminants' milk (buffalo, cow, goat and ewe) throughout the year, raised under the conventional feeding system of Sindh, Pakistan. Milk samples were collected during the four periods of the year; in winter (Dec–Feb), spring (Mar–Apr), summer (May–Sep) and autumn season (Oct–Nov). Animals were fed on seasonal forages except in winter and late spring when shortage of green forage occurs and ruminants were fed crops byproduct and residues (wheat straw, cotton seed cake, rice husk) along with available green fodder. Overall the concentration of short chain FAs ( trans (16–35%) and conjugated linoleic acid contents (24–48%) in comparison to winter milk among ruminant species studied. Results of present study suggest that availability of fresh grass in summer season promotes the synthesis of fatty acids beneficial for human health, including unsaturated and conjugated fatty acids in ruminants' milk, possibly due to altered biohydrogenation pathway and other unidentified characteristics.

This study describes the use of banana peel, a commonly produced fruit waste, for the removal of Cd(II) from environmental and industrial wastewater. The banana peel was characterized by FT-IR and scanning electron microscopy (SEM) coupled with energy dispersive X-ray (EDX) analysis. The parameters pH, contact time, initial metal ion concentration and temperature were investigated and found to be rapid ( approximately 97% within 10 min). The Langmuir adsorption isotherm was used to describe partitioning behavior for the system at room temperature. The value of Q(L) was found to be (35.52 mg g(-1)) higher than the previously reported materials. The binding of metal ions was found to be pH-dependent with the optimal sorption occurring at pH 8. The retained species were eluted with 5 mL of 5 x 10(-3)M HNO(3) with the detection limit of 1.7 x 10(-3)mg L(-1). Kinetics of sorption followed the pseudo-first-order rate equation with the rate constant k, equal to 0.13+/-0.01 min(-1). Thermodynamic parameters such as Gibbs free energy at 303K (-7.41+/-0.13 kJ mol(-1)) and enthalpy (40.56+/-2.34 kJ mol(-1)) indicated the spontaneous and endothermic nature of the sorption process. The developed method was utilized for the removal of Cd(II) ions from environmental and industrial wastewater samples using flame atomic absorption spectrophotometer (FAAS).

A simple, rapid and fairly selective method for the preparation of fatty acid methyl esters (FAMEs) based on anion exchange resin Amberlite IRA-904 catalyzed transesterification of vegetable oil/fat with iodomethane has been described. The vegetable oil and animal fats used were sunflower oil, palm oil, vanaspati (hydrogenated vegetable oil), olive oil, tallow and butter. A Plackett–Burman factorial experimental design was used as a multivariate strategy for the evaluation of the effects of varying several variables at once. The effects of five different variables amount of resin, strength of sodium hydroxide, volume of iodomethane, heating time and temperature of thermostatic water bath, on the yield of fatty acid methyl esters (FAMEs) have been investigated. From these studies, certain variable showed up as significant, and they were optimized by a using 23 + star central composite design, which involved 16 experiments. The best conditions for transesterification reaction were as follows: amount of resin 2 g, strength of sodium hydroxide 0.25 N, volume of iodomethane 400 µl, heating time 2 min at 70 °C. A standard IUPAC method was used to prepare FAMEs from vegetable oil/fats for comparative purpose. Finally samples of oil/fat obtained from both methods were analysed by Gas liquid chromatography. Analytical results for the FAMEs by resin based proposed method, and conventional IUPAC method showed a good agreement, thus indicating the possibility of using Amberlite IRA-904 based transesterification instead of intensive treatments inherent with the conventional time-consuming methods. Industrial relevance Fatty acids are the main components of edible oil and fats, therefore determination of fatty acid composition is so far one of the important parameters for quality evaluation and nutritional value determination of edible oil and fats. The analysis of fatty acid is usually carried out by Gas liquid chromatography (GLC) after conversion of volatile fatty acid methyl esters (FAME) although other ester may be prepared for specific purpose. The endeavor of present work was to improve the FAMEs preparation method, proposing the development of anion exchange resin Amberlite IRA-904 based transesterification of edible oil/fat with iodomethane as alkylating reagent. The present method besides being rapid and reproducible avoids the use of classical saponification, washing of esters and solvent extraction step.

The fat contents of 12 brands of biscuits were extracted and evaluated for free fatty acids (FFA) and their fatty acid composition (FAC). The oil content and FFA varied from 13.7 to 27.6% and 0.2 to 1.0%, respectively. The FAC was analyzed by gas chromatography–mass spectroscopy with particular emphasis on trans fatty acids (TFA). Total saturated, unsaturated, cis-monounsaturated and polyunsaturated fatty acids were determined in the range of 37.9–46.9, 53.0–62.0, 12.3–43.7 and 0.1–9.2%, respectively. The high amount of TFA was observed in all biscuit samples and varied from 9.3 to 34.9%. The quantity and quality of the lipid fraction of the biscuits indicated that the all analyzed biscuits are a rich source of fat, saturated fatty acids and trans fatty acids, consequently not suitable for the health of consumers. The high content of trans fatty acids and palmitic acid also indicated that blends of RBD palm oil and partially hydrogenated oil had been used in the biscuit manufacturing.

Antioxidant potential of four Desi chickpeas (Cicer arietinum L.) varieties indigenous to Pakistan, namely Balksar 2000, CM98, Dasht and Winhar 2000, was evaluated. All studied varieties exhibited appreciable total phenolic content (0.92–1.12 mg gallic acid equivalents/g), total flavonoid content (0.79–0.99 mg catechin equivalent [CAE]/g) and condensed tannin content (0.58–0.69 mg CAE/g). In addition, antioxidant activities were tested using 2,2-diphenyl-1-picrylhydrazyl radical (1.05–1.24 µmol trolox/g), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (37.24–45.32 µmol trolox/g), ferric-reducing antioxidant power (0.73–0.90 mmol Fe2+equivalents/100 g) and oxygen radical-absorbing capacity (8.58–11.4 µmol trolox/g). All varieties exhibited appreciable antioxidant potential and significant differences (P

The aim of this research work is to investigate sorption characteristic of beach sand for the removal of Zn(II) ions from aqueous solutions. The sorption of Zn(II) ions by batch dynamic method is carried out using dilute solutions (10 −4 M) of nitric, hydrochloric and perchloric acids along with deionized water and from buffers of pH 2–10. Maximum sorption is noticed from deionized water (88.3%) using 30 min shaking time. Two equations, i.e. Morris–Weber and Lagergren have been tested to track the kinetics of removal process. The Langmuir, Freundlich and Dubinin–Radushkevich (D–R) model are subjected to sorption data to estimate sorption capacity, intensity and energy. The thermodynamic parameters Δ H , Δ S and Δ G are evaluated. The influence of common ions on the sorption of Zn(II) ions is also examined. Some ions reduce the sorption while most of the ions tested have very little effect. It can be concluded that beach sand has potential to remove Zn(II) ions from aqueous solutions at very low concentrations and for the treatment of industrial effluent carrying Zn(II) ions.

Ten margarine brands of Pakistan were analyzed for their fatty acid composition with emphasis on trans fatty acids (TFA) using GC-MS. Saturated, cis-monounsaturated and polyunsaturated fatty acids were present at 24.2-58.1, 5.7-35.4 and 3.8-37.4% of total fatty acids, respectively. Among the saturated fatty acids, palmitic acid (16.9-33.8%) was dominant in all analyzed margarine brands and its higher amount indicates that palm oil was a major contributor in the margarine manufacturing. Among samples tested only one contained a low level of TFA (2.2%) while the rest contained very high amounts of TFA (11.5-34.8%) which clearly shows that hydrogenated oils were used in the formulation of margarines. Fatty acid profiles demonstrated that all samples belong to the hard margarine category containing high amounts of trans and saturated fatty acids which is an alarming issue for the health of consumers.

A rapid method has been developed to extract and quantitatively measure the total oil content in poultry feeds using a domestic microwave oven. The optimized extraction procedure involves the replicate (6×) extraction of 5 g of ground feed with 12 ml of hexane for 20 s in a 900 W oven. Each replicate involves the collection of the resulting miscella and its replacement with fresh solvent for re-extraction. The collected extracts were centrifuged and transferred to a vial. The solvent was evaporated to a constant weight and the residual lipid weighed. In comparison to conventional Soxhlet extraction method, lipid contents obtained using the optimized microwave procedure was not significantly different. However, FTIR analysis indicated that the microwave procedure was superior in minimizing the formation of free fatty acids (FFA) relative to the Soxhlet procedure if the temperature of the sample was kept within the range of 45–50 °C. This simple, sequential extraction procedure is rapid, highly efficient and provides a simple mean of quantitating the lipid content of poultry feed in less than 40 min without the need for specialized microwave oven.

In the present studies chemically and thermally treated watermelon peels (TWMP) have been utilized for the removal of methyl parathion (MP) pesticide from water. The effect of process variables such as pH of solution, shaking speed, shaking time, adsorbent dose, concentration of solution and temperature have been optimized. Maximum adsorption (99 ± 1%) was achieved for (0.38–3.80) × 10−4 mol dm−3 of MP solution, using 0.1 g of adsorbent in 20 ml of solution for 60 min agitation time at pH 6. BET and SEM analysis have been carried out for the characterization of TWMP. Adsorption data has been analyzed by Freundlich, Langmuir and Dubinin–Radushkevich (D–R) adsorption isotherms. Lagergren, Morris–Weber and Reichenberg equations have been used for kinetic studies of adsorption process. Thermodynamic parameters ΔH, ΔS and ΔG have been calculated. Positive value of ΔH and negative value of ΔG show endothermic and spontaneous nature of adsorption respectively. The developed adsorption method has been employed to surface water samples with percent removal 99% ± 1.

Summary Methanolic extracts of rice bran (MRB) were found to be the richest in phenolics than all the other extraction media, i.e. water, 80% methanol, 70% ethanol, diethyl ether. Thermal stability of MRB was determined by evaluating antioxidant activity of heated extracts in linoleic acid system. Cookies were prepared in sunflower oil premixed with MRB at different concentrations, i.e. 500, 1000 and 2000 ppm, and with butylated hydroxytoluene and α-tocopherol at 200 ppm. Oxidative stability of cookies was measured by storing under ambient conditions for an year with periodical analysis after every 2 months. Fatty acid composition was determined by gas–liquid chromatography. A regular decrease in unsaturated fatty acids (USFA) and increase in saturated fatty acids was observed with the increase in storage period; all the stabilised samples showed appreciably less decrease in USFA than that of control sample. Induction period ranged from 14.73 to 31.22 h while control exhibited 7.5 h. Peroxide value, iodine value and free fatty acids were chosen as the parameters for quality evaluation of cookies. Results suggest rice bran to be a potential source of antioxidants for stabilisation of cookies.

The removal of Cd(II) using polystyrene foam chemically modified with 2,2′-bipyridine has been investigated. The modified polystyrene foam has been characterized by FT-IR spectroscopy, thermogravimetry, elemental analysis and scanning electron microscopy. The solid was employed as a Cd(II) adsorption from aqueous solutions at room temperature. The effects of several variables (pH, shaking speed, agitation time, metal concentration and presence of other ions in the medium) have been studied using batch technique. Flame atomic absorption spectrometry was used to determine the Cd(II) ion concentration in the filtrate after the adsorption process. Maximum sorption ⩾90% was achieved at pH 7 after 30 min of shaking time. Sorbed metal ions have been desorbed with 5 ml of 2 M HNO 3 with the detection limit of 16.7 ng ml −1 . The Langmuir, Freundlich and D–R isotherm equation were used to describe partitioning behavior of the system at room temperature. Kinetic and thermodynamic behavior of modified polystyrene foam for Cd(II) ion removal was also studied. Br − , PO 4 3− , Pb 2+ , Ni 2+ and Cr(VI) suppress the sorption to some extent. The possible sorption mechanism of Cd(II) ions onto modified sorbent is also discussed. Method was utilized to remove Cd(II) ions from aqueous media.

A new simple sensitive differential pulse polarographic (DPP) method was investigated for the determination of acrylamide (AA) directly in a neutral aqueous solution. The AA showed a well-defined and well-resolved peak in pure aqueous LiCl at −1.84 V in the potential range from −1.6 V to −1.97 V at nitrogen pressure of 0.5 kg cm −2 . Among the various electrolytes studied, the AA showed good DPP response in the presence of LiCl and tetra methyl ammonium iodide, while it showed poor response in the presence of tetra butyl ammonium hydroxide and tetra butyl ammonium bromide due to their strong adsorption on the surface of electrode which hindered its reduction. The effect of LiCl concentration, the cyclic voltammetric response and the drop time study showed that AA exhibited an irreversible adsorptive electrochemical behavior. The good electrochemical response in pure aqueous medium suggested that hydrogen bonding might be involved which may favor the electrode reaction. Under optimized conditions, the peak current was linear in the entire concentration range from 0.2 mg L −1 to 20 mg L −1 with the correlation coefficient of R 2 = 0.9998. The method showed good reproducible results with R.S.D. of 0.3% ( n = 16). The detection limit (LOD) was 27 μg L −1 . The influence of various interfering agents was also studied. The method was applied successfully for the quantification of AA in water samples without any interference effect from alkali metals.