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71.
Shanoo Suroowan Eulogio Jose Llorent-Martínez Gokhan Zengin Stefano DallAcqua Stefania Sut Kalaivani Buskaran Sharida Fakurazi Mohamad Fawzi Mahomoodally 《Molecules (Basel, Switzerland)》2022,27(18)
Artemisia verlotiorum Lamotte is recognized medicinally given its long-standing ethnopharmacological uses in different parts of the world. Nonetheless, the pharmacological properties of the leaves of the plant have been poorly studied by the scientific community. Hence, this study aimed to decipher the phytochemicals; quantify through HPLC-ESI-MS analysis the plant’s biosynthesis; and evaluate the antioxidant, anti-tyrosinase, amylase, glucosidase, cholinesterase, and cytotoxicity potential on normal (NIH 3T3) and human liver and human colon cancer (HepG2 and HT 29) cell lines of this plant species. The aqueous extract contained the highest content of phenolics and phenolic acid, methanol extracted the most flavonoid, and the most flavonol was extracted by ethyl acetate. The one-way ANOVA results demonstrated that all results obtained were statistically significant at p < 0.05. A total of 25 phytoconstituents were identified from the different extracts, with phenolic acids and flavonoids being the main metabolites. The highest antioxidant potential was recorded for the aqueous extract. The best anti-tyrosinase extract was the methanolic extract. The ethyl acetate extract of A. verlotiorum had the highest flavonol content and hence was most active against the cholinesterase enzymes. The ethyl acetate extract was the best α-glucosidase and α-amylase inhibitor. The samples of Artemisia verlotiorum Lamotte in both aqueous and methanolic extracts were found to be non-toxic after 48 h against NIH 3T3 cells. In HepG2 cells, the methanolic extract was nontoxic up to 125 µg/mL, and an IC50 value of 722.39 µg/mL was recorded. The IC50 value exhibited in methanolic extraction of A. verlotiorum was 792.91 µg/mL in HT29 cells. Methanolic extraction is capable of inducing cell cytotoxicity in human hepatocellular carcinoma without damaging normal cells. Hence, A. verlotiorum can be recommended for further evaluation of its phytochemical and medicinal properties. 相似文献
72.
Aik Sian Tan Jaymeer Singh Nurul Syafiqah Rezali Musthahimah Muhamad Nik Nur Syazni Nik Mohamed Kamal Yvan Six Mohamad Nurul Azmi 《Molecules (Basel, Switzerland)》2022,27(17)
The Heck cross-coupling reaction is a well-established chemical tool for the synthesis of unsaturated compounds by formation of a new C-C bond. In this study, 1,3-diarylpropene derivatives, designed as structural analogues of stilbenoids and dihydrostilbenoids, were synthesised by the palladium-catalysed reactions of 2-amidoiodobenzene derivatives with either estragole or eugenol. The products were obtained with high (E) stereoselectivity but as two regioisomers. The ratios of isomers were found to be dependent on the nature of the allylbenzene partner and were rationalised by electronic effects exercising a determining influence in the β-hydride elimination step. In addition, the cytotoxic effects of all the Heck reaction products were evaluated against MCF-7 and MDA-MB-231 human breast cancer cells, with unpromising results. Among all, compound 7d exhibited weak cytotoxic activity towards MCF-7 cell lines with IC50 values of 47.92 µM in comparison with tamoxifen and was considered to have general toxicity (SI value < 2). 相似文献
73.
Toutounji M 《Physical chemistry chemical physics : PCCP》2012,14(2):626-636
This study employs mixed quantum-classical dynamics (MQCD) formalism to evaluate the linear electronic dipole moment time correlation function (DMTCF) in which a Morse oscillator serves to model the associated vibrations in a mixed quantum-classical (MQC) environment. While the main purpose of this work is to study the applicability of MQCD formalism to anharmonic systems in condensed phase, approximate schemes to physically evaluate the mathematically divergent integrals have been developed in order to deal with the essential singularities that arise while evaluating the Morse oscillator canonical partition function and the DMTCF in MQC systems in the classical limit. The motivation for numerically and analytically evaluating these divergent integrals is that a partition function of any system should lead to a finite value at any temperature and therefore this divergence is unphysical. Additionally, since a partition function is to signify the number of accessible states to the system at hand, divergent results are not physically acceptable. As such, straightforward approximate analytic expressions, at different levels of rigor, for both the classical Morse oscillator partition function and the DMTCF in MQC systems are derived, for the first time. Calculations of Morse oscillator partition function values using different approaches at various temperatures for CO, HCl, and I(2) molecules, showing good results, are presented to test the expressions derived herein. It is found that this divergence, due to singularity, diminishes upon lowering the temperature and only arises at high temperatures. The gradual diminishing of the singularity upon lowering the temperature is sensible since the Morse potential fits the parabolic potential at low temperatures. Model calculations and discussion of the DMTCF and linear absorption spectra in MQC systems using the molecular constants of CO molecule are provided. The linear absorption lineshape is derived by two methods, one of which is asymptotic expansion. 相似文献
74.
Faraji Hakim Saber-Tehrani Mohamad Mirzaie Afshin Waqif-Husain Syed 《平面色谱法杂志一现代薄层色谱法》2011,24(3):214-217
JPC – Journal of Planar Chromatography – Modern TLC - A novel liquid-phase microextraction method coupled with high-performance thin-layer chromatography (HPTLC) for preconcentration,... 相似文献
75.
In this paper, a new channel drop filter in two dimensional photonic crystals with mirror cavities is proposed. In the structure,
three cavities are used. One is used for a resonant tunneling-based channel drop filter. The others are used to realize reflection
feedback in the bus waveguide, which consists of a point defect micro-cavity side-coupled to a waveguide. The simulation results
by using the finite-difference time-domain method conclude 98% output efficiency. 相似文献
76.
77.
Laili Mahmoudian Jonas Melin Mohamad Reza Mohamadi Keiko Yamada Michio Ohta Noritada Kaji Manabu Tokeshi Mats Nilsson Yoshinobu Baba 《Analytical sciences》2008,24(3):327-332
We have developed a new method for a fast and precise analysis of circle-to-circle amplification (C2CA) product for specific gene detection by microchip electrophoresis. In this method, we have added a new enzymatic step to the C2CA reaction, which could be carried out isothermally at 37 degrees C. Compared to the original single-stranded DNA, the double-stranded DNA that is produced by this enzymatic reaction is more reliable for analysis by microchip electrophoresis. C2CA product was detected within 55 s with high reproducibility by this method which was successfully applied to the detection of 10-ng genomic DNA of the pathogenic bacteria Vibrio. cholerae within 110 s. Purification was found to be an indispensable step for the analysis of the C2CA product of genomic DNA samples. 相似文献
78.
Jacques Lalevée Mohamad El‐Roz Xavier Allonas Jean Pierre Fouassier 《Journal of polymer science. Part A, Polymer chemistry》2008,46(6):2008-2014
New systems for the visible‐light‐induced polymerization of cationic resins working through a free‐radical‐promoted process are presented. They are based on a photoinitiator (camphorquinone, isopropylthioxanthone, Eosin), a silane, and a diphenyl iodonium salt, the new compound being the silane. The overall efficiency is strongly affected by the silane structure. The rates of polymerization and final percent conversion are noticeably higher than those obtained in the presence of already studied reference systems. Moreover, contrary to previously investigated free‐radical‐promoted cationic polymerizations, oxygen does not inhibit the process and an unusual enhancement of the polymerization kinetics is found in aerated conditions: such an observation seems to have never been reported so far. The excited state processes and the role of oxygen as revealed by laser flash photolysis are discussed. The particular behavior of the silyl radicals is outlined. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2008–2014, 2008 相似文献
79.
We study the filling invariants at infinity div
k
for Hadamard manifolds defined by Brady and Farb [ Trans. Am. Math. Soc. 350(8) (1998), 3393–3405]. Among other results, we give a positive answer to the question they posed: whether these invariants
can be used to detect the rank of a symmetric space of noncompact type. 相似文献
80.
I.J Mohamad L.Zammit Mangion E.F Lambson G.A Saunders 《Journal of Physics and Chemistry of Solids》1982,43(8):749-759
Simultaneous visual observation and monitoring of the ultrasonic signals show that acoustic emission (AE) produced as Pb5Ge3O11c-plate crystals undergo the ferroelectric hysteresis cycle results from domain wall nucleation and collapse. AE activity takes place predominantly at applied electric fields large enough to bring a crystal substantially towards its saturation polarisation. A notable feature observed in Pb5Ge3O11 and Pb5?xBaxGe3O11 alloys is the existence of an abrupt threshold electric field, denoted by E∞ in the high gain limit, for production of AE: as the electric field is increased beyond the threshold value, the amount of AE observed increases by several orders of magnitude. E∞ depends linearly on the inverse of the c-plate sample thickness (1/d) and also upon sample temperature—falling to a minimum at about 70°C for Pb5Ge3O11 and then rising steeply as the Curie temperature (178°C) is approached. E∞ is also dependent on the rate of change of the applied electric field and as this is increased extrapolates to the high frequency limit of the coercive field. Measurements of crystal polarisation indicate a one-to-one correspondence between AE and the electrical Barkhausen pulses which occur during polarisation reversal—further evidence for domain nucleation and collapse as the source of AE. Optical and AE studies made simultaneously on gadolinium molybdate add confirmation that these particular processes are responsible for the AE produced by ferroelectric crystals. 相似文献