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Growing research on beans suggest that they are good for health, as they reduce the risk and/or help in the management of chronic diseases. Beans are valuable parts of several dietary recommendations. Saponins, α-galactosides, phytates, and lectins are currently drawing attention because of their diverse properties, both adverse and beneficial. The aim was to determine the hepatotoxic effect of dry red kidney beans, i.e. Phaseolus vulgaris, on rabbits at 4 g kg–1, 6 g kg–1, and 8 g kg–1 dosing for the period of 30 days. The histopathological examination revealed inflammation of hepatocyte at all three doses along with congestion. The biochemical testing of liver enzymes revealed elevated alanine transaminase (ALT), aspartate transaminase (AST) and gamma-glutamyl transferase (γ-GT). The dose-dependent increase in liver enzymes indicates the hepatotoxic effect of dry red kidney beans, and various studies have demonstrated that lectins are the toxic components responsible for inflammation of body organs.

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Abstract  

The concentration of radioactive226Ra,232Th and40K in building and ceramic materials of Bangladesh was investigated by γ-spectrometry with two HPGe detectors. Radium equivalent activities, representative level index values, criterion formula, emanation coefficients and222Rn mass exhalation rates were estimated for the radiation hazard of the natural radioactivity in the materials. The activity concentrations of the natural radionuclides, radium equivalent activities, emanation coefficients and222Rn mass exhalation rates are compared with the corresponding values for building and ceramic materials of different countries. The radium equivalent activities in the samples varied between 30.9 (mosaic stone) and 328.0 Bq·kg−1 (gypsum). The emanation coefficient of the materials ranged from 7.83 (cement) to 33.0% (soil) and the222Rn mass exhalation rate ranged from 2.31 (stone chips) to 118.0 μBq·kg−1·s−1 (gypsum).

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In this paper we present a brief review of the current state of positron annihilation research into the phase behaviour of fluids confined within restricted boundaries. We summarise, in the form of selected examples, the work done so far on: (1) fluids confined in the nanometer-size pores of VYCOR glass, with particular emphasis on the confined phase diagram and the mechanisms behind phase transitions compared to bulk. (2) The adsorption/physisorption of gases on internal surfaces of grafoil and the potential of positron technique for revealing physical properties, such as the intricate molecular arrangements during phase transitions of the layered fluid.

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Abstract  

In confined (nanometer-scale) geometry, the effects of substrate forces and finite size produce a shift of the gas liquid phase boundary from that found in corresponding bulk. The pore transitions also show marked hysteresis. The phase behaviour of a binary gas mixture in confined geometry is likely to depend on the miscibility of the system and the interaction between the substrate and the individual fluid molecules/atoms. Here, we present the results of a pilot positronium annihilation study of the condensation and evaporation of argon-nitrogen mixtures confined in 4 nm diameter cylindrical pores in VYCOR glass.

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Abstract  

The phase behaviour of carbon dioxide confined in VYCOR glass at pressures below that of the bulk triple point (0.51 MPa) has been investigated. The temperature at which freezing occurs appears to be pressure dependent below 0.3 MPa. As experiments are performed at successively lower pressures, the confined phase transitions gradually disappear, due to either partial pore filling, or the proximity of the confined triple point.

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Abstract  

Positron lifetime spectroscopy has been applied to estimate the free-volume hole size distribution in glassy polycarbonate (PC) and polystyrene (PS) as well as in plastically deformed and undeformed, semi-crystalline polyethylene (HDPE). The hole radius density distribution is determined from the ortho-positronium lifetime distribution which is obtained via a Laplace-inversion of the positron lifetime spectrum. The hole volume density distribution and the number density distribution of holes is estimated from the hole radius density distribution. In PC and in PS all of the distributions may be well approximated by a single Gaussian. The hole radius and the hole number density distributions have centres <r> and <v n> at 0.29 nm and 0.1 nm3 in PC, and at 0.28 nm and 0.09 nm3 in PS. The FWHM of the corresponding distributions are 0.042 nm and 0.040 nm3 (PC), and 0.039 nm and 0.34 nm3 (PS), respectively. Both, the shape and the width of the distributions correlate well with the free volume theory of BUECHE. In PE the lifetime spectra consist of four components. The o-Ps lifetime distribution is bimodal and may be attributed to o-Ps annihilation in the crystalline and in the amorphous phase of the polymer. The corresponding hole size distributions show definite changes of their position and width following plastic deformation which we attribute to homogeneous crystal lattice dilatation and/or a local disorder in the crystals and to an increase in the eccentricity of holes in the amorphous phase.

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Genetic relationships among 24 genotypes of Hyophila involuta collected from five different natural populations of Mount Abu (Rajasthan) is analysed using RAPD and SSR markers. Based on efficiency parameters calculated for each marker system such as polymorphic information content (RAPD = 0.34; SSR = 0.66), marker index (RAPD = 2.78; SSR = 2.62) and resolving power (RAPD = 8.13; SSR = 2.23), the RAPD marker system shows higher values for some indices but microsatellites are more accurately reproducible than RAPD. Moreover, in case of the SSR, the average number of alleles was almost twice compared to RAPD. Mean coefficient of genetic differentiation between populations with RAPD was Gst = 0.269, while with SSR marker was Fst = 0.224. The UPGMA cluster analysis assembled genotypes into two main clusters with diverse levels of sub-clustering within the clusters. Also, the Mantel test showed no significant correlation between geographical and genetic distances. The observed moderately high genetic variability can be explained by efficient spore dispersal. Other factors such as reproductive mode, somatic mutation, continuous propagule recruitment and high degree of intermingling have great impact on the level of genetic variability in moss populations.

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Extensive research on Ficus species has shown their excellent cytotoxic potential which motivated the authors for further evaluation of its other species. In this article, the β-sitosterol content in the chloroform extract of the leaves of five Ficus species (Ficus carica [FCCE], Ficus nitida [FNCE], Ficus ingens [FICE], Ficus palmata [FPCE], and Ficus vasta [FVCE]) was estimated by a validated high-performance thin-layer chromatography (HPTLC) method along with cytotoxic activity. The chromatography was performed on glass-backed silica gel 60 F254 HPTLC plates with hexane and ethyl acetate (8:2, v/v) as the mobile phase. The developed plate was derivatized with p-anisaldehyde reagent, scanned, and quantified at λ = 550 nm. It furnished a compact and intense peak of β-sitosterol at R F = 0.17 ± 0.001. The contents of β-sitosterol (μg mg−1 of the dried weight of the extract) in the selected Ficus species were found as: FCCE (1.047 μg mg−1) > FVCE (0.771 μg mg−1) > FNCE (0.372 μg mg−1) > FPCE (0.309 μg mg−1), while it was absent in F. ingens. Methylthiazol tetrazolium (MTT) assay was used to compare the cytotoxic potential of all Ficus species against HepG2 (liver), HEK-293 (kidney), MCF-7 (breast), and MDA-MB 231 (breast) cell lines. The FCCE exhibited good cytotoxic property against HepG2, HEK-293, and MDA-MB-231 cells (IC50: 32.5, 41.4, and 47.3 μg mL−1, respectively), while FICE showed against HepG2 and MDA-MB-231 cells (IC50: 31.4 and 41.2 μg mL−1, respectively). The remaining Ficus extracts were found to be very less effective or insignificant. The cytotoxic property of FCCE is also supported by the HPTLC estimation of β-sitosterol which is reported to exhibit anticancer properties by interfering with multiple cell signaling pathways, including cell cycle, apoptosis, and proliferation. Our data suggest that the developed HPTLC method can be further employed in the analysis of marketed herbal formulations, and the active Ficus species can be further subjected to isolation of cytotoxic phytoconstituents.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors: Omer A. Basudan, Perwez Alam, Nasir A. Siddiqui, Mohamed F. Alajmi, Adnan J. Alrehaily, Saleh I. Alqasoumi, Maged S. Abdel-Kader, Prawez Alam, and Abd El Raheim M. Donia

A simple and sensitive high-performance thin-layer chromatographic (HPTLC) method was developed for the evaluation of biomarker β-amyrin in the leaves of fve different species of genus Ficus (Ficus carica, Ficus nitida, Ficus ingens, Ficus palmata, and Ficus vasta) grown in the Kingdom of Saudi Arabia. Chromatography was performed on glass-backed silica gel 60 F254 HPTLC plates with solvents toluene–methanol (9:1, v/v) as the mobile phase. After development, the HPTLC plate was derivatized with p-anisalde-hydereagent to give well-resolved and compact spot of β-amyrin. Scanning and quantifcation were done at 550 nm. The system was found to give compact spot for β-amyrin at R F = 0.58. The linear regression analysis data for the calibration plots showed good linear relationship with r 2 = 0.998 with respect to area in the concentration range of 100–900 ng. The regression equation for β-amyrin standard was found to be Y = 5.835X + 87. The precisions (n = 6) for β-amyrin were found to be 1.64–1.77% and 1.68–1.84%, respectively, for intra-day and inter-day batches, and the recovery values were found to be 97.6–98.3%. β-Amyrin was found to be present in three species, i.e., F. carica (0.29%, w/w), F. nitida (0. 5 4% w/w), and F. p almata (0.31%, w/w), while it was absent in F. vasta and F. ingens. The statistical analysis proves that the developed method for the quantifcation of β-amyrin is reproducible; hence, it can beemployed for the determination of β-amyrin in plasma and other biological fuids as well as in fnished products avai lable in the market.

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In order to breed rice cultivars for resistance to the brown planthopper, Nilaparvata lugens Stål (BPH) in Bangladesh, were evaluated for resistance in greenhouse screening tests. Over a period of six years (2005–2010), 1,767 entries/cultivars were screened using the plant hopper screening (PHS) system. The results showed 87 donors possessing different levels of resistance to the BPH. One exotic cultivar was highly resistant to the BPH and 86 materials showed medium resistance (tolerance) to the BPH. The rest of the materials including germplasm, F2, exotic, IRBPHN (International Rice Brown Planthopper Nursery) and advanced lines were susceptible. Most of entries coming from the International Rice Research Institute (IRRI) via the IRBPHN were moderately resistant.

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