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171.
Ragaa A. Hamouda Mervat H. Hussein Noura El-Ahmady El-Naggar Mohammed A. Karim-Eldeen Khalid H. Alamer Muneera A. Saleh Luluah M. Al Masoudi Eman M. Sharaf Reham M. Abd El-Azeem 《Molecules (Basel, Switzerland)》2022,27(4)
Seaweeds can play a vital role in plant growth promotion. Two concentrations (5 and 10 mg/mL) of soluble polysaccharides extracted from the green macroalgae Ulva fasciata and Ulva lactuca were tested on Zea mays L. The carbohydrate and protein contents, and antioxidant activities (phenols, ascorbic, peroxidase, and catalase) were measured, as well as the protein banding patterns. The soluble polysaccharides at 5 mg/mL had the greatest effect on the base of all of the parameters. The highest effects of soluble polysaccharides on the Zea mays were 38.453, 96.76, 4, 835, 1.658, 7.462, and 38615.19, mg/mL for carbohydrates, proteins, phenol, µg ascorbic/mL, mg peroxidase/g dry tissue, and units/g tissue of catalase, respectively. The total number of protein bands (as determined by SDS PAGE) was not changed, but the density of the bands was correlated to the treatments. The highest band density and promoting effect were correlated to 5 mg/mL soluble polysaccharide treatments extracted from Ulva fasciata in Zea mays, which can be used as a biofertilizer. 相似文献
172.
Majid Sharifi-Rad Pawel Pohl Francesco Epifano Gokhan Zengin Nidal Jaradat Mohammed Messaoudi 《Molecules (Basel, Switzerland)》2022,27(5)
The aim of the present study was to investigate the changes in the content of phytochemical compounds and in vitro antioxidant, antibacterial, and anti-inflammatory activities of Teucrium polium L. aerial parts and root methanolic extracts at different phenological stages (vegetative, flowering, and seeding). The T. polium extracts were analyzed using gas chromatography–mass spectrometry (GC-MS), and their antioxidant properties were tested with the 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), ferrous ions (Fe2+), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) methods. Forty-nine compounds were identified with the majority of germacrene D, t-cadinol, β-pinene, carvacrol, bicyclogermacrene, α-pinene, and limonene. The results show that the extracts significantly differ between different phenological stages of the plant material used in terms of the phytochemical composition (total phenolic compounds, total flavonoids, total alkaloids, and total saponin contents) and bioactivities (antioxidant, antibacterial, and anti-inflammatory) (p < 0.05). The highest total contents of phenolics (72.4 ± 2.5 mg gallic acid equivalent (GAE)/g dry weight), flavonoids (36.2 ± 3.1 mg quercetin equivalent (QE)/g dry weight), alkaloids (105.7 ± 2.8 mg atropine equivalent (AE)/g dry weight), and saponins (653 ± 6.2 mg escin equivalent (EE)/g dry weight), as well as antioxidant, antibacterial, and anti-inflammatory activities, were measured for the extract of the aerial parts obtained at the flowering stage. The minimum inhibitory concentration (MIC) values for the extracts were varied within 9.4–300 µg/mL, while the minimum bactericidal concentration (MBC) values were varied within 18.75–600 µg/mL. In addition, they were more active on Gram-positive bacteria than Gram-negative bacteria. The data of this work confirm that the T. polium extracts have significant biological activity and hence can be used in the pharmaceutical industry, clinical applications, and medical research, as well as cosmetic and food industries. 相似文献
173.
Thiochloroarsenates (III): Preparation, Vibrational Spectra, and Crystal Structures of PPh4[As2SCl5] and (PPh4)2[As2SCl6] · C2H4Cl2 PPh4[As2SCl5] can be obtained from As2S3 + PPh4Cl with HCl in CH2Cl2 or 1,2-C2H4Cl2. It reacts with a second mole of PPh4Cl to yield (PPh4)2[As2SCl6]. The latter also is formed by the reaction of As2S5 + 2 PPh4Cl with HCl, a second product being (PPh4)2[As2Cl8]. The i.r. and Raman spectra of the title compounds are reported. Their crystal structures were determined by X-ray diffraction. Crystal data: PPh4[As2SCl5], monoclinic, space group P21/n, a = 1175.8, b = 1508.0, c = 1593.4 pm, β = 96.22°, Z = 4; (PPh4)2[As2SCl6] · C2H4Cl2, triclinic, P1, a = 1166.3, b = 1188.2, c = 2044.6 pm, α = 95.47, β = 97.53, γ = 111.05°, Z = 2. Including the lone electron pairs, the coordination of the As atoms in the [As2SCl5]− ion is distorted trigonal-bipyramidal with the S, one Cl atom, and an electron pair in equatorial positions; the two bipyramids around the two As atoms share a common edge. The As atoms in the [As2SCl6]2− ion have a distorted octahedral coordination, the two octahedra share a common face; the lone electron pairs are in the trans positions to the S atom. 相似文献
174.
Mandeep Kumar Arora Anish Ratra Syed Mohammed Basheeruddin Asdaq Ali A. Alshamrani Abdulkhaliq J. Alsalman Mehnaz Kamal Ritu Tomar Jagannath Sahoo Jangra Ashok Mohd Imran 《Molecules (Basel, Switzerland)》2022,27(6)
Plumbagin, a hydroxy-1,4-naphthoquinone, confers neuroprotection via antioxidant and anti-inflammatory properties. The present study aimed to assess the effect of plumbagin on behavioral and memory deficits induced by intrahippocampal administration of Quinolinic acid (QA) in male Wistar rats and reveal the associated mechanisms. QA (300 nM/4 μL in Normal saline) was administered i.c.v. in the hippocampus. QA administration caused depression-like behavior (forced swim test and tail suspension tests), anxiety-like behavior (open field test and elevated plus maze), and elevated anhedonia behavior (sucrose preference test). Furthermore, oxidative–nitrosative stress (increased nitrite content and lipid peroxidation with reduction of GSH), inflammation (increased IL-1β), cholinergic dysfunction, and mitochondrial complex (I, II, and IV) dysfunction were observed in the hippocampus region of QA-treated rats as compared to normal controls. Plumbagin (10 and 20 mg/kg; p.o.) treatment for 21 days significantly ameliorated behavioral and memory deficits in QA-administered rats. Moreover, plumbagin treatment restored the GSH level and reduced the MDA and nitrite level in the hippocampus. Furthermore, QA-induced cholinergic dysfunction and mitochondrial impairment were found to be ameliorated by plumbagin treatment. In conclusion, our results suggested that plumbagin offers a neuroprotective potential that could serve as a promising pharmacological approach to mitigate neurobehavioral changes associated with neurodegeneration. 相似文献
175.
Mohammed A. Al-Nuri Nidal A. Za'tar Maher A. Abu-Eid Mohammad A. Hannoun Waheed J. Al-Jondi Ahmad I. Hussein 《光谱学快报》2013,46(8):1539-1543
A new method for isolation and specrophotometric determination of emodin is presented. Emodin was isolated by thin layer chromatography (tlc) and column chromatography (cc) techniques, as an orange long crystalline substance. Emodin exhibits two absorption maxima, at 420 and 520 nm. Stability of the color and the effect of pH were studied. Beer's law is obeyed in the range 2–30 ppm. The method is applied to the determination of emodin in roots, stems, and leaves of Rumex cyprius plant. 相似文献
176.
D. Kamińska A. Gajos E. Czerwiński D. Alfs T. Bednarski P. Białas C. Curceanu K. Dulski B. Głowacz N. Gupta-Sharma M. Gorgol B. C. Hiesmayr B. Jasińska G. Korcyl P. Kowalski W. Krzemień N. Krawczyk E. Kubicz M. Mohammed Sz. Niedźwiecki M. Pawlik-Niedźwiecka L. Raczyński Z. Rudy M. Silarski A. Wieczorek W. Wiślicki B. Zgardzińska M. Zieliński P. Moskal 《The European Physical Journal C - Particles and Fields》2016,76(8):445
177.
178.
This paper provides simulation comparisons among the performance of 11 possible prediction intervals for the geometric.mean of a Pareto distribution with parameters (αB, ). Six different procedures were used to obtain these intervals , namely; true inter -val , pivotal interval , maximum likelihood estimation interval, centrallimit teorem interval, variance stabilizing interval and a mixture of the above intervals . Some of these intervals are valid if the observed sample size m,are large , others are valid if both, n and the future sample size m, are large. Some of these intervals require a knowledge of α or B, while others do not. The simulation validation and efficiency study shows that intervals depending on the MLE's are the best. The second best intervalsare those obtained through pivotal methods or variance stabilization transformation. The third group of intervals is that which depends on the central limit theorem when λ is known. There are two intervals which proved to be unacceptable under any criterion. 相似文献
179.
This paper presents a novel geometric non-linear finite element formulation for the analysis of shear deformable two-layer beams with interlayer slips. We adopt the co-rotational approach where the motion of the element is decomposed into two parts: a rigid body motion which defines a local coordinate system and a small deformational motion of the element relative to this local coordinate system. The main advantage of this approach is that the transformation matrices relating local and global quantities are independent to the choice of the geometrical linear local element. The effect of transverse shear deformation of the layers is taken into account by assuming that each layer behaves as a Timoshenko beam element. The layers are assumed to be continuously connected and partial interaction is considered by considering a continuous relationship between the interface shear flow and the corresponding slip. In order to avoid curvature and shear locking phenomena, the local linear element is formulated using “exact” displacement shape functions derived from the closed-form solution of the governing equations of a two-layer beam element. Finally, three numerical applications are presented in order to assess the performance of the proposed formulation. 相似文献
180.