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51.
Hafedh Hajlaoui Soumaya Arraouadi Emira Noumi Kaïss Aouadi Mohd Adnan Mushtaq Ahmad Khan Adel Kadri Mejdi Snoussi 《Molecules (Basel, Switzerland)》2021,26(12)
Herbs and spices have been used since antiquity for their nutritional and health properties, as well as in traditional remedies for the prevention and treatment of many diseases. Therefore, this study aims to perform a chemical analysis of both essential oils (EOs) from the seeds of Carum carvi (C. carvi) and Coriandrum sativum (C. sativum) and evaluate their antioxidant, antimicrobial, anti-acetylcholinesterase, and antidiabetic activities alone and in combination. Results showed that the EOs mainly constitute monoterpenes with γ-terpinene (31.03%), β-pinene (18.77%), p-cymene (17.16%), and carvone (12.20%) being the major components present in C. carvi EO and linalool (76.41%), γ-terpinene (5.35%), and α-pinene (4.44%) in C. sativum EO. In comparison to standards, statistical analysis revealed that C. carvi EO showed high and significantly different (p < 0.05) antioxidant activity than C. sativum EO, but lower than the mixture. Moreover, the mixture exhibited two-times greater ferric ion reducing antioxidant power (FRAP) (IC50 = 11.33 ± 1.53 mg/mL) and equipotent chelating power (IC50 = 31.33 ± 0.47 mg/mL) than the corresponding references, and also potent activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC50 = 19.00 ± 1.00 mg/mL), β-carotene (IC50 = 11.16 ± 0.84 mg/mL), and superoxide anion (IC50 = 10.33 ± 0.58 mg/mL) assays. Antimicrobial data revealed that single and mixture EOs were active against a panel of pathogenic microorganisms, and the mixture had the ability to kill more bacterial strains than each EO alone. Additionally, the anti-acetylcholinesterase and α-glucosidase inhibitory effect have been studied for the first time, highlighting the high inhibition effect of AChE by C. carvi (IC50 = 0.82 ± 0.05 mg/mL), and especially by C. sativum (IC50 = 0.68 ± 0.03 mg/mL), as well as the mixture (IC50 = 0.63 ± 0.02 mg/mL) compared to the reference drug, which are insignificantly different (p > 0.05). A high and equipotent antidiabetic activity was observed for the mixture (IC50 = 0.75 ± 0.15 mg/mL) when compared to the standard drug, acarbose, which is about nine times higher than each EO alone. Furthermore, pharmacokinetic analysis provides some useful insights into designing new drugs with favorable drug likeness and safety profiles based on a C. carvi and C. sativum EO mixture. In summary, the results of this study revealed that the combination of these EOs may be recommended for further food, therapeutic, and pharmaceutical applications, and can be utilized as medicine to inhibit several diseases. 相似文献
52.
Nadjette Debbouche Shaher Momani Adel Ouannas Mohd Taib Shatnawi Giuseppe Grassi Zohir Dibi Iqbal M. Batiha 《Entropy (Basel, Switzerland)》2021,23(3)
This article investigates a non-equilibrium chaotic system in view of commensurate and incommensurate fractional orders and with only one signum function. By varying some values of the fractional-order derivative together with some parameter values of the proposed system, different dynamical behaviors of the system are explored and discussed via several numerical simulations. This system displays complex hidden dynamics such as inversion property, chaotic bursting oscillation, multistabilty, and coexisting attractors. Besides, by means of adapting certain controlled constants, it is shown that this system possesses a three-variable offset boosting system. In conformity with the performed simulations, it also turns out that the resultant hidden attractors can be distributively ordered in a grid of three dimensions, a lattice of two dimensions, a line of one dimension, and even arbitrariness in the phase space. Through considering the Caputo fractional-order operator in all performed simulations, phase portraits in two- and three-dimensional projections, Lyapunov exponents, and the bifurcation diagrams are numerically reported in this work as beneficial exit results. 相似文献
53.
Remon M. Zaki Adel M. Kamal El-Dean Jehan A. Mickey Nermin A. Marzouk Rasha H. Ahmed 《合成通讯》2017,47(24):2406-2416
Ethyl 4,6-dimethyl-3-(pyrrol-1-yl) selenolo[2,3-b]pyridine-2-carboxylate (2) was synthesized by the reaction of previously prepared ethyl 3-amino-4,6-dimethyl selenolo[2,3-b]pyridine-2-carboxylate (1) with 2,5-dimethoxytetrahydrofuran in acetic acid. The pyrrolyl ester (2) was converted into the corresponding carbohydrazide 3 which reacted with acetyl acetone, aromatic aldehydes, carbon disulfide in pyridine, and sodium nitrite to afford the corresponding dimethyl pyrazolyl 4, arylidene carbohydrazides 5a–d, oxadiazolyl thiole 6, and caboazide compound 8, respectively. The carboazide 8 reacted with different alcohols and amines to give the corresponding carbamates 9a–c and the aryl urea derivatives 10a–d. Heating of carboazide 8 in dry xylene afforded the pyridoselenolo-pyrrolopyrazinone 11. The latter compound was used as a versatile starting precursor for synthesis of other pyridoselenolo-pyrrolopyrazine compounds. The newly synthesized compounds and their derivatives were characterized by elemental analysis and spectroscopy (IR, 1H-NMR, and mass spectra). Some of the newly synthesized pyrrolyl selenolopyridine compounds showed remarkable antioxidant activity compared to ascorbic acid. 相似文献
54.
Austin B. Yongye Marc A. Giulianotti Adel Nefzi Richard A. Houghten Karina Martínez-Mayorga 《Journal of computer-aided molecular design》2010,24(3):225-235
The potential energy surfaces of chiral tetraamine Pt(II) coordination complexes were computed at the B3LYP/LANL2DZ level
of theory by a systematic variation of two dihedral angles: C12–C15–C34–C37 (θ) and C24–C17–C31–C48 (ψ) employing a grid resolution
of 30°. Potential energy surfaces calculated using density functional theory methods and Boltzmann-derived populations revealed
strong preference for one diasteromer of each series studied. In addition, natural bond orbital analysis show that the minima
are stabilized predominantly by a combination of electronic interactions between two phenyl groups, the phenyl groups and
the Pt2+ ion, as well as with the amine groups. Additional experimental characterization of the diasteroisomers studied here is in
progress and will permit further molecular modeling studies with the appropriate stereochemistry. 相似文献
55.
Adel F. Halasa Chad Jusinas Wen-Liang Hsu David J. Zanzig 《European Polymer Journal》2010,46(10):2013-2018
The present work is to the syntheses and characterization of random, low vinyl copolymers containing styrene and isoprene (SIR’s). The content of these SIR’s ranged from 10% styrene/90% isoprene to 60% styrene/40% isoprene, and all were soluble in hexane solvent. The anionic polymerization of these SIR’s was initiated by a catalyst system of various sodium dodecylbenzene sulfonate (SDBS) to n-butyllithium (n-BuLi) ratios. The SDBS allowed for styrene to become randomly incorporated onto the polyisoprene chain without any increase in the 3,4-unit of the isoprene. The glass transition temperature of the resulting polymers could be controlled by the styrene content and microstructure (blocky versus random) in the polymer chain. Kinetic data confirmed that styrene and isoprene have similar reaction kinetics. NMR and ozonolysis confirmed that random, low vinyl SIR’s were indeed being synthesized. The unique features of this system are that it does not metallate the polymers as was seen in the previous publication using the sodium and potassium alkoxides. Molecular weight differences due to SDBS are discussed. Finally, rubber process analyzer (RPA) results were presented for various styrenes content SIR’s. 相似文献
56.
57.
58.
This paper aims to present a general framework of the quadratic spline functions to develop a numerical method for solving the nonlinear space fractional Fisher's equation. Using Von Neumann method, the proposed method is shown to be conditionally stable. Finally, a numerical example is given to verify the effectiveness of the proposed algorithm. The results reveal that the proposed approach is very effective, convenient, and quite accurate to such considered problems. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
59.
In this paper, we propose a new model for the search and rescue problem. We focus on the case of a single airborne search asset through a connected space and continuous time with a maximum travel time \(T\) . The intent is to maximize the detection of a cooperative target (search and rescue). The proposed model is based on the assumption of existing a priori information (e.g., result of information fusion process) to establish a spatial distribution of probability of containment in possible geographic locations. The possibility area is defined using a cut threshold on the probability of containment and the search path as well as the allocation of the level of effort to each region in the search space is obtained based on an orienteering model. We illustrate the application of the proposed model on an empirical example. 相似文献
60.
Chahra Bouchameni Chahrazed Beghidja Adel Beghidja Pierre Rabu Richard Welter 《Polyhedron》2011,30(11):1774-1778
Two new complexes [MnIII(HL)2(acac)] and [MnII(HL)2]n have been obtained by reacting manganese(III) acetylacetonate monohydrate or manganese(II) chloride monohydrate with 2-salicylichydrazono-1,3-dithiolane ligand (H2L). Both compounds have been fully characterized by spectroscopic methods and single crystal X-ray diffraction. In the solid state, the molecular packing are described and discussed in term of weak H-bonds and short contacts. The unprecedented bridging coordination mode of this ligand lead to the first 2-salicylichydrazono-1,3-dithiolane-bridged coordination polymer [MnII(HL)2]n. The EPR spectrum of this compound was obtained with g ≈ 2.07, corresponding to a manganese ion (+II) in octahedral high-spin coordination sphere. The MnII complex exhibit paramagnetic behavior corresponding to quasi-isolated metal centers. 相似文献