Syed Ghulam Musharraf

Biotransformation of adrenosterone by filamentous fungus, Cunninghamella elegans

Microbial transformation of adrenosterone (1) by suspended-cell cultures of the filamentous fungus Cunninghamella elegans resulted in the production of five metabolites 2-6, which were identified as 9alpha-hydroxyadrenosterone (2), 11-ketotestosterone (3), 6beta-hydroxyadrenosterone (4), 9alpha-hydroxy-11-ketotestosterone (5), and 6beta-hydroxy-11-ketotestosterone (6). Structures of new metabolites 2, 5, and 6 were established by single-crystal X-ray diffraction analysis.

Antioxidant and hepatoprotective activity appraisal of four selected Fumaria species and their total phenol and flavonoid quantities

Fumaria species (Fumariaceae) have been recorded to be used traditionally against liver-related disorders in many countries including Turkey. Oxidative stress is also known to be strongly associated with hepatic problems. Consequently, in the current study, the ethanol extracts of four Fumaria species; F. cilicica Hausskn., F. densiflora DC., F. kralikii Jordan and F. parviflora Lam. growing in Turkey were initially screened for their in vitro antioxidant activities by three methods; 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging test, Fe(+2)-ferrozine test system for metal chelating test and ferric-ion reducing antioxidant power (FRAP) at 250, 500 and 1000 μg/ml concentrations. Then, each of the ethanol extracts was fractionated into petroleum ether, chloroform, ethyl acetate and methanol fractions and their antioxidant activities were estimated by DPPH radical scavenging and xanthine oxidase inhibition tests at 1000 μg/ml. In both tests, the chloroform and ethyl acetate fractions of F. cilicica were found to be the most active and were further investigated in in vivo hepatoprotective activity experiment against toxicity induced by CCl(4). Total phenol and flavonoid quantities of the ethanol extracts were determined spectrophotometrically using Folin-Ciocalteaus and AlCl(3) reagents, respectively. Our data revealed that the chloroform and ethyl acetate fractions of F. cilicica did not have hepatoprotective effect and the ethanol extracts exerted low antioxidant activity. Although protective effect of some Fumaria species in hepatic diseases was shown in several previous studies, this record seems to be not pertinent for F. cilicica.

Application of analytical methods in authentication and adulteration of honey.

Honey is synthesized from flower nectar and it is famous for its tremendous therapeutic potential since ancient times. Many factors influence the basic properties of honey including the nectar-providing plant species, bee species, geographic area, and harvesting conditions. Quality and composition of honey is also affected by many other factors, such as overfeeding of bees with sucrose, harvesting prior to maturity, and adulteration with sugar syrups. Due to the complex nature of honey, it is often challenging to authenticate the purity and quality by using common methods such as physicochemical parameters and more specialized procedures need to be developed. This article reviews the literature (between 2000 and 2016) on the use of analytical techniques, mainly NMR spectroscopy, for authentication of honey, its botanical and geographical origin, and adulteration by sugar syrups. NMR is a powerful technique and can be used as a fingerprinting technique to compare various samples.

New oxandrolone derivatives by biotransformation using Rhizopus stolonifer

Structural transformation of the steroidal lactone, oxandrolone (1), by suspended-cell cultures of the plant pathogen fungus Rhizopus stolonifer, resulted in the production of three new metabolites. These metabolites were identified as 11alpha-hydroxyoxandrolone (2), 6alpha-hydroxyoxandrolone (3) and 9alpha-hydroxyoxandrolone (4), by different spectroscopic methods and single-crystal X-ray diffraction analysis for metabolite 2. Compounds 1 and 3 showed a significant beta-glucuronidase inhibitory activity.

Biodiesel production from microalgal isolates of southern Pakistan and quantification of FAMEs by GC-MS/MS analysis

BackgroundMicroalgae have attracted major interest as a sustainable source for biodiesel production on commercial scale. This paper describes the screening of six microalgal species, Scenedesmus quadricauda, Scenedesmus acuminatus, Nannochloropsis sp., Anabaena sp., Chlorella sp. and Oscillatoria sp., isolated from fresh and marine water resources of southern Pakistan for biodiesel production and the GC-MS/MS analysis of their fatty acid methyl esters (FAMEs).ResultsGrowth rate, biomass productivity and oil content of each algal species have been investigated under autotrophic condition. Biodiesel was produced from algal oil by acid catalyzed transesterification reaction and resulting fatty acid methyl esters (FAMEs) content was analyzed by GC/MS. Fatty acid profiling of the biodiesel, obtained from various microalgal oils showed high content of C-16:0, C-18:0, cis-Δ9C-18:1, cis-Δ11C-18:1 (except Scenedesmus quadricauda) and 10-hydroxyoctadecanoic (except Scenedesmus acuminatus). Absolute amount of C-14:0, C-16:0 and C-18:0 by a validated GC-MS/MS method were found to be 1.5-1.7, 15.0-42.5 and 4.2-18.4 mg/g, respectively, in biodiesel obtained from various microalgal oils. Biodiesel was also characterized in terms of cetane number, kinematic viscosity, density and higher heating value and compared with the standard values.ConclusionSix microalgae of local origin were screened for biodiesel production. A method for absolute quantification of three important saturated fatty acid methyl esters (C-14, C-16 and C-18) by gas chromatography-tandem mass spectrometry (GC-MS/MS), using multiple reactions monitoring (MRM) mode, was employed for the identification and quantification of biodiesels obtained from various microalgal oils. The results suggested that locally found microalgae can be sustainably harvested for the production of biodiesel. This offers the tremendous economic opportunity for an energy-deficient nation.

Versatile nanocomposites in phosphoproteomics: a review.

Protein phosphorylation is one of the most important post-translational modifications. Phosphorylated peptides are present in low abundance in blood serum but play a vital role in regulatory mechanisms and may serve as casual factors in diseases. The enrichment and analysis of phosphorylated peptides directly from human serum and mapping the phosphorylation sites is a challenging task. Versatile nanocomposites of different materials have been synthesized using simple but efficient methodologies for their enrichment. The nanocomposites include magnetic, coated, embedded as well as chemically derivatized materials. Different base materials such as polymers, carbon based and metal oxides are used. The comparison of nanocomposites with respective nanoparticles provides sufficient facts about their efficiency in terms of loading capacity and capture efficiency. The cost for preparing them is low and they hold great promise to be used as chromatographic materials for phosphopeptide enrichment. This review gives an overview of different nanocomposites in phosphoproteomics, discussing the improved efficiency than the individual counterparts and highlighting their significance in phosphopeptide enrichment.

Quantitative analysis of some important metals and metalloids in tobacco products by inductively coupled plasma-mass spectrometry (ICP-MS)

BackgroundLarge scale usage of tobacco causes a lot of health troubles in human. Various formulations of tobacco are extensively used by the people particularly in developing world. Besides several toxic tobacco constituents some metals and metalloids are also believed to pose health risks. This paper describes inductively coupled plasma-mass spectrometric (ICP-MS) quantification of some important metals and metalloids in various brands of smoked, sniffed, dipped and chewed tobacco products.ResultsA microwave-assisted digestion method was used for sample preparation. The method was validated by analyzing a certified reference material. Percentage relative standard deviation (% R.S.D.) between recovered and certified values was < 5.8. Linearity value for calibration curve of each metal was 1 > r > 0.999. Improved limits of detection (LODs) were in range of ng/L for all elements. Fe, Al and Mn were found to be in the highest concentration in all types of tobacco products, while Zn, Cu, Ni and Cr were below the average concentration of 40 μg/g, and Pb, Co, As, Se and Cd were below 5 μg/g. All elements, apart from Pb, were high in concentration in dipping tobacco in comparison to other tobacco products. Generally, the order of all elemental concentration can be expressed in different tobacco products as chewing < smoked < sniffing < dipping. However, smoked and sniffing will interchange their position in the case of Mn, Cu, Se and Cd. Multivariate statistical analyses were also performed to evaluate the correlation and variations among tobacco products.ConclusionsThe present study highlights the quantification of some important metals and metalloids in a wide spectrum of tobacco formulations. The outcome of this study would be beneficial for health authorities and individuals.

Analysis and development of structure‐fragmentation relationships in withanolides using an electrospray ionization quadropole time‐of‐flight tandem mass spectrometry hybrid instrument

Structural elucidation and gas-phase fragmentation of ten withanolides (steroidal lactones) were studied using a positive ion electrospray ionization quadropole time-of-flight mass spectrometry (ESI-QqTOF-MS/MS) hybrid instrument. Withanolides form an important class of plant secondary metabolites, known to possess a variety of biological activities. Withanolides which possess hydroxyl groups at C-4, C-5, C-17, C-20, and C-27, and an epoxy group at C-5/C-6, were evaluated to determine the characteristic fragments and their possible pathways. ESI-QqTOF-MS (positive ion mode) showed the presence of the protonated molecules [M + H](+) . Low-energy collision-induced dissociation tandem mass spectrometric (CID-MS/MS) analysis of the protonated molecule [M + H](+) indicated multiple losses of water and the removal of the C-17-substituted lactone moiety affording the [M + H-Lac](+) product ion as the predominant pathways. However, withanolides containing a hydroxyl group at C-24 of the lactone moiety showed a different fragmentation pathway, which include the loss of steroidal part as a neutral molecule, with highly diagnostic ions at m/z 95 and 67 being generated from the cleavage of lactone moiety. Our results also determined the influence of the presence and positions of hydroxyl and epoxy groups on product ion formation and stability. Moreover, the knowledge of the fragmentation pattern was utilized in rapid identification of withanolides by the LC/MS/MS analysis of a Withania somnifera extract.

Cycloartane triterpenoids from Astragalus bicuspis.

Three new cycloartane glycosides have been isolated from Astragalus bicuspis. They were identified as 6alpha-hydroxy-3-O-beta-xylopyranosyloxy-24,25,26,27-tetranor-9,19-cyclolanosta-16,23-lactone (1), 6alpha-hydroxy-23-methoxy-16beta,23(R)-epoxy-24,25,26,27-tetranor-9,19-cyclolanosta-3-O-beta-xyloside (2), and 23(R),24(S),25(R),26(S)-16beta/23,23/26,24/25-triepoxy-6alpha,26-dihydroxy-9,19-cyclolanosta-3-O-beta-xyloside (3), on the basis of their spectroscopic data. Two known cycloartane derivatives, 4 and 5, were also obtained from this plant. Compounds 2-5 were tested for leishmanicidal activity against Leishmania major promastigotes and for cytotoxicity against 3T3 cancer cells.

Stress degradation studies and development of stability-indicating TLC-densitometry method for determination of prednisolone acetate and chloramphenicol in their individual and combined pharmaceutical formulations

A rapid and reproducible stability indicating TLC method was developed for the determination of prednisolone acetate and chloramphenicol in presence of their degraded products. Uniform degradation conditions were maintained by refluxing sixteen reaction mixtures for two hours at 80°C using parallel synthesizer including acidic, alkaline and neutral hydrolysis, oxidation and wet heating degradation. Oxidation at room temperature, photochemical and dry heating degradation studies were also carried out. Separation was done on TLC glass plates, pre-coated with silica gel 60F-254 using chloroform: methanol (14:1 v/v). Spots at Rf 0.21 ± 0.02 and Rf 0.41 ± 0.03 were recognized as chloramphenicol and prednisolone acetate, respectively. Quantitative analysis was done through densitometric measurements at multiwavelength (243 nm, λmax of prednisolone acetate and 278 nm, λmax of chloramphenicol), simultaneously. The developed method was optimized and validated as per ICH guidelines. Method was found linear over the concentration range of 200-6000 ng/spot with the correlation coefficient (r2 ± S.D.) of 0.9976 ± 3.5 and 0.9920 ± 2.5 for prednisolone acetate and chloramphenicol, respectively. The developed TLC method can be applied for routine analysis of prednisolone acetate and chloramphenicol in presence of their degraded products in their individual and combined pharmaceutical formulations.