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31.
Antioxidant and Anti-Inflammatory Effects of Peganum harmala Extracts: An In Vitro and In Vivo Study
Malik Waseem Abbas Mazhar Hussain Muhammad Qamar Sajed Ali Zahid Shafiq Polrat Wilairatana Mohammad S. Mubarak 《Molecules (Basel, Switzerland)》2021,26(19)
Peganum harmala (P. harmala) belongs to the family Zygophyllaceae, and is utilized in the traditional medicinal systems of Pakistan, China, Morocco, Algeria, and Spain to treat several chronic health disorders. The aim of the present study was to identify the chemical constituents and to evaluate the antioxidant, anti-inflammatory, and toxicity effects of P. harmala extracts both in vitro and in vivo. Sequential crude extracts including 100% dichloromethane, 100% methanol, and 70% aqueous methanol were obtained and their antioxidant and anti-inflammatory effects evaluated both in vitro and in vivo. The anti-inflammatory effect of the extract was investigated using the carrageenan-induced paw edema method in mice, whereas the toxicity of the most active extract was evaluated using an acute and subacute toxicity rat model. In addition, we have used the bioassay-guided approach to obtain potent fractions, using solvent–solvent partitioning and reversed phase high performance liquid chromatography from active crude extracts; identification and quantification of compounds from the active fractions was achieved using electrospray ionization mass spectrometry and high performance liquid chromatography techniques. Results revealed that the 100% methanol extract of P. harmala exhibits significant in vitro antioxidant activity in DPPH assay with an IC50 of 49 µg/mL as compared to the standard quercetin with an IC50 of 25.4 µg/mL. The same extract exhibited 63.0% inhibition against serum albumin denaturation as compared to 97% inhibition by the standard diclofenac sodium in an in vitro anti-inflammatory assay, and in vivo anti-inflammatory against carrageenan-induced paw edema (75.14% inhibition) as compared to 86.1% inhibition caused by the standard indomethacin. Furthermore, this extract was not toxic during a 14 day trial of acute toxicity when given at a dose of 3 g/kg, indicating that the lethal dose (LD50) of P. harmala methanol extract was greater than 3 g/kg. P. harmala methanolic fraction 2 obtained using bioassay-guided fractionation showed the presence of quinic acid, peganine, harmol, harmaline, and harmine, confirmed by electrospray ionization mass spectrometry and quantified using external standards on high performance liquid chromatography. Taken all together, the current investigation further confirms the antioxidant, anti-inflammatory, and safety aspects of P. harmala, which justifies its use in folk medicine. 相似文献
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Abida Kalsoom M. Mazhar Saqib Ali M. F. Mahon K. C. Molloy M. Iqbal Chaudry 《应用有机金属化学》1997,11(1):47-55
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In this paper, a sensitive water-soluble fluorescent conjugated polymer biosensor for catecholamine (dopamine DA, adrenaline AD and norepinephrine NE) was developed. In the presence of horse radish peroxidase (HRP) and H(2)O(2), catecholamine could be oxidized and the oxidation product of catecholamine could quench the photoluminescence (PL) intensity of poly(2,5-bis(3-sulfonatopropoxy)-1,4-phenylethynylenealt-1,4-poly(phenylene ethynylene)) (PPESO(3)). The quenching PL intensity of PPESO(3) (I(0)/I) was proportional to the concentration of DA, AD and NE in the concentration ranges of 5.0 × 10(-7) to 1.4 × 10(-4), 5.0 × 10(-6) to 5.0 × 10(-4), and 5.0 × 10(-6) to 5.0 × 10(-4) mol L(-1), respectively. The detection limit for DA, AD and NE was 1.4 × 10(-7) mol L(-1), 1.0 × 10(-6) and 1.0 × 10(-6) mol L(-1), respectively. The PPESO(3)-enzyme hybrid system based on the fluorescence quenching method was successfully applied for the determination of catecholamine in human serum samples with good accuracy and satisfactory recovery. The results were in good agreement with those provided by the HPLC-MS method. 相似文献
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Karm Hans Masood Parvez Sumera Mahboob Imtiaz‐ud‐Din Muhammad Mazhar Saqib Ali 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):m559-m562
The central Ge atoms in the structures of 3‐(2‐fluorophenyl)‐3‐(triphenylgermyl)propionic acid, [Ge(C6H5)3(C9H8FO2)], 3‐(2‐tolyl)‐3‐(tri‐4‐tolylgermyl)propionic acid, [Ge(C7H7)3(C10H11O2)], and 3‐(4‐tolyl)‐3‐(tribenzylgermyl)propionic acid, [Ge(C7H7)3(C10H11O2)], are four‐coordinate with slightly distorted tetrahedral geometry. The Ge—Csp3 distances [1.970 (3)–1.997 (3) Å] are significantly longer than the Ge—Caromatic distances [1.940 (3)–1.959 (2) Å]. In all three structures, the molecules form dimeric pairs about inversion centres through strong hydrogen‐bonding interactions between carboxylic acid groups. 相似文献
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Shelf life of the formulations designed for the industrial manufacture of radiation sterilizable syringes and other medical disposables is a very important issue world over. Radiation compatible formulations were developed earlier in the laboratory by the incorporation of primary and secondary antioxidants along with processing stabilizers in a random polypropylene copolymer. It has been reported in literature that the mobilizing agents namely hydrocarbons, greases, wax and the plasticizer, dioctyl phthalate (DOP) impart radiation resistance to the polypropylene by providing free volume. It was envisaged that the addition of DOP to the afore-mentioned formulation might favorably influence the mechanical, optical and thermal properties of our formulation. To study the influence of addition of DOP on the afore-mentioned properties, the addition of 1%, 2% and 3% of the mobilizer was made, followed by the irradiation of resulting heat pressed sheets to the industrial standard dose of 25 kGy. Two important characteristic mechanical properties to determine the suitability of the radiation sterilized materials comprise angle of breakage and the haze percent. After irradiation and even on accelerated ageing of the irradiated material, the angle of breakage of heat press sheets of formulations containing 1%, 2% and 3% of DOP was found to be 180°, demonstrating the role of DOP, in imparting additional radiation stability. In case of the irradiated control sample, the angle of breakage was much lower. In the heat pressed sheets containing the DOP, a remarkable retention in the tensile strength, percentage elongation at break, along with improved thermal stability was observed. The formulation devoid of DOP demonstrated poor retention of the afore-mentioned characteristic properties .The observed improvement in thermal stability of the formulations containing DOP hints at the likely possibility of reuse of these materials by autoclaving which is considered an additional attribute. 相似文献
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The mechanism of the fluxional process occurring in dimeric tetraorganodicarboxylato stannoxanes is presented on the basis of multinuclear NMR studies carried out in noncoordinating solvents. This fluxional process is a consequence of rapid migration of carboxylate groups from one tin atom to the other. It has been proposed that larger carboxylates will also execute this behavior. The effect of cis and trans positions on the fluxional process is discussed. The fluxional process is very fast and could not be stopped even at low temperatures, as measured on the NMR time scale. © 1996 John Wiley & Sons, Inc. 相似文献