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21.
Taha Alqahtani Sajida Parveen Yahia Alghazwani Hanan M. Alharbi Reem M. Gahtani Nadia Hussain Kashif ur Rehman Musaddique Hussain 《Molecules (Basel, Switzerland)》2022,27(14)
Oxidative stress is the key factor that strengthens free radical generation which stimulates lung inflammation. The aim was to explore antioxidant, bronchodilatory along with anti-asthmatic potential of folkloric plants and the aqueous methanolic crude extract of Ipomoea nil (In.Cr) seeds which may demonstrate as more potent, economically affordable, having an improved antioxidant profile and providing evidence as exclusive therapeutic agents in respiratory pharmacology. In vitro antioxidant temperament was executed by DPPH, TFC, TPC and HPLC in addition to enzyme inhibition (cholinesterase) analysis; a bronchodilator assay on rabbit’s trachea as well as in vivo OVA-induced allergic asthmatic activity was performed on mice. In vitro analysis of 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH) expressed as % inhibition 86.28 ± 0.25 with IC50 17.22 ± 0.56 mol/L, TPC 115.5 ± 1.02 mg GAE/g of dry sample, TFC 50.44 ± 1.06 mg QE/g dry weight of sample, inhibition in cholinesterase levels for acetyl and butyryl with IC50 (0.60 ± 0.67 and 1.5 ± 0.04 mol/L) in comparison with standard 0.06 ± 0.002 and 0.30 ± 0.003, respectively, while HPLC characterization of In.Cr confirmed the existence with identification as well as quantification of various polyphenolics and flavonoids i.e., gallic acid, vanillic acid, chlorogenic acid, quercetin, kaempferol and others. However, oral gavage of In.Cr at different doses in rabbits showed a better brochodilation profile as compared to carbachol and K+-induced bronchospasm. More significant (p < 0.01) reduction in OVA-induced allergic hyper-responses i.e., inflammatory cells grade, antibody IgE as well as altered IFN-α in airways were observed at three different doses of In.Cr. It can be concluded that sound mechanistic basis i.e., the existence of antioxidants: various phenolic and flavonoids, calcium antagonist(s) as well as enzymes’ inhibition profile, validates folkloric consumptions of this traditionally used plant to treat ailments of respiration. 相似文献
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The solute quenching studies of a lectin from endophytic fungus Fusarium solani were carried out using different quenchers such as acrylamide, succinimide, potassium iodide and cesium chloride. The lectin
showed emission maximum at 348 nm indicating relative exposure of tryptophan. The quenchable fraction of the fluorophore was
100% with acrylamide, whereas it was only 50% with succinimide. The ionic quenchers iodide and cesium showed opposite effects
at different pH. In the case of cesium, raising the pH resulted in increased quenching and accessibility of typtophan residue,
while the iodide showed just opposite effect. These studies showed that the single tryptophan residue of the lectin (per monomer)
is relatively exposed, and might be in the vicinity of positively charged amino acid residues. Various amino acids of the
F. solani lectin were modified using different reagents to obtain information about the hemagglutinating site. The chemical modification
studies suggested tyrosine residues can be modified using N-acetylimidazole, which results in complete loss of hemagglutination
activity of the lectin. Kinetics of chemical modification suggested involvement of only 2 tyrosine residues. Modification
of arginine, cysteine, histidine, lysine, aspartate, glutamate and tryptophan did not result in loss of hemagglutinating activity
of the lectin. 相似文献
23.
Nasima Arshad Naghmana Rashid Sajida Absar Muhammad S. A. Abbasi Samreen Saleem Bushra Mirza 《Central European Journal of Chemistry》2013,11(12):2040-2047
Two flavonoids, karanjin (Kj) and karanjachromene (Kc) have been investigated spectrophotometrically for their mode of interactions with double stranded (ds)-DNA at blood (7.4) and stomach (4.7) pH and at human body temperature (37°C). Benesi-Hildebrand equation was used to evaluate the binding constants, K b . Binding constants at both pH values and at body temperature showed stronger binding of both the flavonoids and formation of 1:1 flavonoid-DNA complex via intercalative mode. However, K b values for karanjin were evaluated to be comparatively greater than karanjachromene at both pH values. The highest value of binding constant (1.32×105 M?1) for karanjin at blood pH (7.4) demonstrated its comparatively stronger binding and greater effectiveness at this pH. Standard Gibbs free energy changes (ΔG) of flavonoid-DNA complexes were calculated as negative values and indicative of spontaneity of their binding. Both flavonoids showed significant DNA protection activity. 相似文献
24.
Sajida Ahmed 《Tetrahedron letters》2004,45(31):6045-6047
A convenient and flexible synthesis of meso-tetraaryl porphyrins substituted with three thioglycosyl units, and also bearing one pyridyl substituent is reported. Quaternisation of the pyridine nitrogen with alkyl iodides gives access to a range of water soluble glycosyl cationic porphyrins. Screening for photodynamic activity against human colorectal adenocarcinoma cells (HT-29) indicates that all the glycosyl cationic porphyrins made in this way are active photosensitisers, but direct comparison with a cationic porphyrin bearing no sugar residues indicates an important role for these groups in reducing generalised `dark' toxicity. 相似文献
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Wave functions have been determined for the C2H4PH and C2H4S cyclic molecules, using (951/52/3) and (95/52/3) uncontracted Gaussian basis sets for each molecule. From Mulliken population analyses and electron-density plots, it is shown that the valence orbitals of C2H4PH and C2H4S are closely related and that these are similar to the respective orbitals of cyclopropane.
Zusammenfassung Für die zyklischen Moleküle C2H4PH und C2H4S wurden mit den nichtkontrahierten Basissätzen ((951/52/3) und (95/52/3)) von Gaußfunktionen Wellenfunktionen bestimmt. Die Mullikenschen Populationsanalysen sowie Diagramme der Elektronendichte zeigen, daß die Valenzorbitale von C2H4PH und C2H4S in enger Beziehung stehen und daß diese den entsprechenden Orbitalen des Cyclopropans ähnlich sind.相似文献
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Three galactose‐specific lectins have been isolated and purified from the extract of pumpkin seed kernels by gel filtration on Sephadex G‐75 with 100% ammonium sulfate saturated crude extract, followed by ion exchange chromatography on DEAE‐cellulose and affinity chromatography on Sepharose 4B. All three lectins were found to be homogeneous as judged by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE). The molecular weights of lectins, PSL‐1, PSL‐2 and PSL‐3, as estimated by gel filtration on Sephadex G‐75 were 40,000, 42,000 and 46,000, and by SDS‐PAGE about 39,500, 41,000 and 45,000, respectively. The lectins, PSL‐1, PSL‐2 & PSL‐3 were dimer in nature and the molecular weights of their subunits were about 25,500 and 14,000; 26,000 and 15,000; and 30,500 and 15,000, respectively. The lectins are glycoproteins with a neutral sugar content of 3‐5%. The lectins agglutinated rat red blood cells and the hemagglutination was inhibited specifically by galactose and galactose‐containing saccharides. The lectins exhibited a strong cytotoxic effect in a brine shrimp lethality bioassay. 相似文献
29.
Shahanaz Khatun M. Ashraduzzman N. Absar F. Pervin M. Abbas Ali Luthfunnesa Bari M. R. Karim Parvez Hassan 《中国化学会会志》2007,54(2):357-364
Three lectins designated as SLL‐1, SLL‐2 and SLL‐3 were purified from small sized Sajna (Moringa oleifera L.) leaves by gel filtration of 100% ammonium sulfate saturated crude protein extract on Sephadex G‐75 followed by ion‐exchange chromatography on DEAE and affinity chromatography on Sepharose‐4B. The molecular weight of the lectins SLL‐1, SLL‐2 and SLL‐3 were 1,55,000, 1,15,000 and 85,000, respectively, as determined by gel filtration on Sephadex G‐150 and 1,60,000; 1,20,000 and 85,500, respectively, by SDS‐polyacrylamide slab gel electrophoresis. SLL‐1 and SLL‐2 are dimer in nature held together by disulfide bond (s), while SLL‐3 is a monomer. The lectins agglutinated specifically rat red blood cells and the agglutination was inhibited specifically by methyl‐α‐D‐galactopyranoside, methyl‐β‐D‐galactopyranoside and D‐galactose. The lectins SLL‐1, SLL‐2 and SLL‐3 contain 3.9, 3.4 and 2.8% neutral sugar, respectively, and the sugar compositions were glucose for SLL‐1, mannose for SLL‐2 and SLL‐3 contained either N‐acetyl‐D‐glucosamine or N‐acetyl‐D‐galactosamine or both. The lectins exhibited cytotoxicity in brine shrimp lethality bioassay. 相似文献
30.
A decomposition of an N-particle operator as a sum of N + 1 components is defined such that, in the case of a model system employing a finite one-particle basis set, the decomposition is invariant under unitary transformations of the basis set. Applied to a two-particle Hamiltonian, this decomposition gives rise to the distinction between the independent-particle energy and the coupling energy defined in previous papers. Applied to the reduced density operator for a quantum state, the decomposition corresponds to partitioning the density into irreducible components. This partitioning is illustrated by graphs of electron density for the water molecule. 相似文献