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Bis(salicylaldehyde) orthophenylenediamine as complexing reagent in simultaneous determination of gold, chromium, iron, uranyl, and nickel using capillary zone electrophoresis

100%

Soomro R. , Memon S. Q. , Ahmed M. J. , Memon N. , Mallah A.

Acta Chromatographica

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2012

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tom Vol. 24, no. 4

543--558

EN

Bis(salicylaldehyde) orthophenylenediamine (BSOPD) is reported here as a complexing reagent for simultaneous determination of six metal ions, gold, chromium, iron(II)/(III), uranyl, and nickel, by capillary zone electrophoresis. The pre-derivatized complexes were injected onto 50 cm bare silica capillary (i.d. 75 µm) with background electrolyte 50 mM citrate:oxalate buffer in 1:1 at pH 4. All metal ions were separated within 15 min including coexisted ions at applied voltage of −15 kV at detection wavelength of 250 nm. Under the abovementioned conditions, limits of quantification and detection were found to be 0.5, 1.0, 1.0, 10.0, 1.0, and 10.0 µg mL-1; and 0.16, 0.33, 0.33, 3.33, 0.33, and 3.33 µg mL-1 for Au(III), Cr(VI), Fe(III), Fe(II), UO2(II), and Ni(II), respectively. Linear calibration graphs were obtained in the ranges of 0.5–100, 1–200, 10–100, 1–100, 1–100, and 10–200 µg mL-1 with the correlation coefficient values 0.9964, 0.9948, 0.9900, 0.9999, 0.9992, and 0.9918 for Au(III); and Cr(VI), Fe(III), Fe(II), UO2(II), and Ni(II), respectively. Applicability of the method has been evaluated by determining gold from wastewater samples of goldsmith factories and uranyl from ore samples. The developed method was also used for the determination of chromium in selected environmental waters (drinking and polluted). The data obtained with developed method were compared with those obtained from atomic absorption spectroscopy, and the results of the analysis were found to be in good agreement.

2

Physiochemical characterization of Bauhinia purpurea seed oil and meal for nutritional exploration

100%

Arain S. , Sherazi S. T. H. , Bhanger M. I. , Mahesar S. A. , Memon N.

Polish Journal of Food and Nutrition Sciences

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2010

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tom 60

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nr 4

EN

The present study deals with characterisation of Bauhinia purpurea seed oil and meal for the quality evaluation. The characteristics of the extracted oil and the seed residue (meal) were determined out for their possible utilizations. The extracted oil was also analysed for iodine value, saponification value, unsaponifiable matter, acid value, peroxide value, refractive index and colour values. Fatty acid composition analysis by gas chromatography has shown that linoleic (55.34%) and oleic (11.84%) acids were the predominant unsaturated fatty acids, while palmitic acid (17.47%) and stearic acid (11.40%) were the major saturated fatty acids. Three tocopherols and six phytosterols were identified and quantified; among these, α-tocopherol and β-sitosterol was predominant, respectively. The physiochemical characteristics has revealed that Bauhinia purpurea oil has nutritive and dietetic potentialities. While proximate analysis of meal has shown that it my be used in the manufacturing of poultry and animal feeds.

3

Phenolic acids profiling and antioxidant potential of mulberry (Morus laevigata W., Morus nigra L., Morus alba L.) leaves and fruits grown in Pakistan

100%

Memon A. A. , Memon N. , Luthria D. L. , Bhanger M. I. , Pitafi A. A.

Polish Journal of Food and Nutrition Sciences

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2010

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tom 60

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nr 1

EN

Mulberry trees are distributed throughout Pakistan. Besides its use in forage and food for animals, it is also used as herbal medicine. This study is carried out to determine phenolic acids profile, sugar content, and the antioxidant activity of the leaves and fruits of three mulberry species (Morus alba L., Morus nigra L. and Morus laevigata W.) grown in Pakistan. Dried fruits and leaves of three mulberry plant species were extracted by three different methods. The extracts were analysed by HPLC with diode array detection for phenolic acids. Antioxidant activity and sugar content were determined using spectrophotometric assays. The structure of chlorogenic acid was confirmed by LC-MS/MS analysis. The major phenolic acids were identified as gallic, protocatechuic, p-hydroxybenzoic, vanillic, chlorogenic, syringic, p-coumaric, ferulic and m-coumaric acids. Chlorogenic acid was the prominent phenolic acid in all leaves samples collected from three mulberry species and optimum extraction of chlorogenic acid was achieved using 80% aqueous methanol with ultrasonic-assisted extraction. Total phenolic compounds as determined by Folin-Ciocalteu assay were in the range of 3.89 to 11.79 mmol/ 100 g gallic acid equivalent, whereas antioxidant activities by DPPH assay ranged from 22.85–76.88 μmol/100 g quercetin equivalent. The concentration of sugars in different samples ranged between 36.56-82.15 mmol/ 100 g sucrose equivalent. This is the first report on identification of phenolic acids and antioxidant activity in the extracts of three cultivars of mulberry plants grown in Pakistan. This information will be of considerable value to the commercial producers of mulberry trees in the country.