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Introduction: Nymphaea rubra belongs to the Nymphaea family and is regarded as a vegetable used in traditional medicine to cure several ailments. These species are rich in phenolic acid, flavonoids, and hydrolysable tannin. Objective: This study aimed to assess the biological activities of Nymphaea rubra flowers (NRF) and leaves (NRL) by identifying and quantifying their polyphenolic compounds using ultra‐performance liquid chromatography coupled to quadrupole cyclic ion mobility time‐of‐flight mass spectrometry (UHPLC‐Q‐cIM‐TOF‐MS) and triple quadrupole mass spectrometry (UHPLC‐TQ‐MS). Methodology: NRF and NRL powder was extracted with methanol and fractionated using hexane, ethylacetate, and water. Antioxidant and α‐glucosidase, and tyrosinase enzyme inhibitory activities were evaluated. The polyphenolic components of NRF and NRL were identified and quantified using UHPLC‐Q‐cIM‐TOF‐MS and UHPLC‐TQ‐MS. The method was validated using linearity, precision, accuracy, limit of detection (LOD), and lower limit of quantification (LLOQ). Results: Bioactive substances and antioxidants were highest in the ethylacetate fraction of flowers and leaves. Principal component analysis showed how solvent and plant components affect N. rubra's bioactivity and bioactive compound extraction. A total of 67 compounds were identified, and among them 21 significant polyphenols were quantified. Each calibration curve had R2 > 0.998. The LOD and LLOQ varied from 0.007 to 0.09 μg/mL and from 0.01 to 0.1 μg/mL, respectively. NRF contained a significant amount of gallic acid (10.1 mg/g), while NRL contained abundant pentagalloylglucose (2.8 mg/g). Conclusion: The developed method is simple, rapid, and selective for the identification and quantification of bioactive molecules. These findings provide a scientific basis for N. rubra's well‐documented biological effects. This study presents a straightforward, expeditious, and highly discerning approach for the identification and quantification of bioactive molecules within Nymphaea rubra flower (NRF) and leaves (NRL). The findings reveal that NRF is particularly rich in gallic acid (GA), boasting a noteworthy concentration of 10.1 mg/g, whereas NRL exhibits abundance in pentagalloylglucose (PGG) at 2.8 mg/g. Furthermore, both NRF and NRL exhibit robust antioxidant, α‐glucosidase, and tyrosinase enzyme inhibition activities, attributed plausibly to the presence of GA and PGG. [ABSTRACT FROM AUTHOR]

Owing to the increasing environmental and climate changes globally, there is an increasing interest in the molecular‐level understanding of environmental organic compound mixtures, that is, the pursuit of complete and detailed knowledge of the chemical compositions and related chemical reactions. Environmental organic molecule mixtures, including those in air, soil, rivers, and oceans, have extremely complex and heterogeneous chemical compositions. For their analyses, ultrahigh‐resolution and sub‐ppb level mass accuracy, achievable using Fourier‐transform ion cyclotron resonance mass spectrometry (FT‐ICR MS), are important. FT‐ICR MS has been successfully used to analyze complex environmental organic molecule mixtures such as natural, soil, particulate, and dissolved organic matter. Despite its success, many limitations still need to be overcome. Sample preparation, ionization, structural identification, chromatographic separation, and data interpretation are some key areas that have been the focus of numerous studies. This review describes key developments in analytical techniques in these areas to aid researchers seeking to start or continue investigations for the molecular‐level understanding of environmental organic compound mixtures. [ABSTRACT FROM AUTHOR]

Mononuclear Co(II), Zn(II) and Cd(II) complexes derived from bidentate or tridentate N,N',N-bis((1H-pyrazol-1-yl)methyl)amines (Ln = LA, LB), where LA is N,N-bis((1H-pyrazol-1-yl)methyl)-3-methoxypropan-1-amine and LB is 3-methoxy-N,N-bis((3,5-dimethyl-1H-pyrazol-1-yl)methyl)propan-1-amine, have been synthesized and characterized. The geometry at Co(II) and Cd(II) for [LACoCl2], [LBCoCl2] and [LBCdBr2] with N,N',N-tridentate ligands (Ln = LA, LB) can be described as a distorted trigonal bipyramid achieved by coordinative interaction of Npyrazole, two halides and the nitrogen of amine moiety. However, the molecular structure of four-coordinate [LAZnCl2] can be best described as tetrahedral, resulting in an eight-membered chelate ring. [LACoCl2] polymerized methyl methacrylate in the presence of modified methylaluminoxane at 60 °C and resulted in poly(methylmethacrylate) (PMMA) with higher molecular weight and narrower polydispersity index compared to the other synthesized complexes. However, all the synthesized complexes yielded syndiospecific PMMA, characterized using 1H NMR spectroscopy, with ca. 0.70. [ABSTRACT FROM AUTHOR]

The structural refinement of SnO2 thin film prepared by PECVD was performed by the Rietveld method using X-ray diffraction data. The agreement between calculated and observed patterns was not satisfactory, which was attributed to the preferred orientation effect. The effect of preferred orientation was corrected by three kinds of approaches: a March–Dollase function, a pole density distribution using an inverse pole figure and a generalized spherical harmonic function. Of these methods, the approach using the generalized spherical harmonic function was the most effective than the other two approaches. The final residual weighted R-factor, Rwp, was converged 7.92%. The lattice parameters were a=b=4.7357(2) and c=3.1937(2). Other structural parameters were well in accordance with those of SnO2 powder. [Copyright &y& Elsevier]

The phosphor, BaMgAl10O17:Eu2+, showing a blue emission band at about 450 nm was prepared by a normal solid-state reaction using BaCO3, Al2O3, MgO and Eu2O3 as starting materials with AlF3 as a flux. The study of combined Rietveld refinement and photoluminescence spectra was carried out to determine the structural parameters, such as lattice constants, the valence state of Eu, the site preference of Mg and site fractions of Mg and Eu. The occupancies of Eu and Mg were 0.022 and 0.526, respectively. The valence state of Eu was the divalent state because there was only one broad line at about 450 nm in the photoluminescence spectrum. The site preference of Mg atoms was the tetrahedral site of Al atoms surrounded by oxygen atoms in the spinel block. Lattice parameters decreased due to the difference of two ionic radii, Eu2+(1.09 A˚) and Ba2+(1.34 A˚), compared with those of BaMgAl10O17. [Copyright &y& Elsevier]

Abstract: The binding mode of Δ- and Λ-[Ru(1,10-phenanthroline)2dipyrido[3,2-a:2′,3′-c]phenazine]2+ ([Ru(phen)2DPPZ]2+) to DNA in the presence of 4′,6-diamidino-2-phenylindole (DAPI) at a low and high [DAPI]/[DNA base] ratio (0.02 and 0.20, respectively) was investigated using electric absorption and circular dichroism spectroscopy. The spectral properties of both the Δ- and Λ-[Ru(phen)2DPPZ]2+ were not altered in the presence of DAPI disregarding the [DAPI]/[DNA] ratio, suggesting that the presence of DAPI in the minor groove of DNA does not affect the binding mode of the [Ru(phen)2DPPZ]2+ complex to DNA. The transferring excited energy of DAPI to both Δ- and Λ-[Ru(phen)2DPPZ]2+ occurs through Förster type resonance when they both spontaneously bound to DNA. At a high [DAPI]/[DNA] ratios, an upward bending curve in the Stern–Volmer plot, and a shortening the DAPI fluorescence decay time with increasing [Ru(phen)2DPPZ]2+ concentration were found. These results indicate that the quenching of the DAPI''s fluorescence occurs through both the static and dynamic mechanisms. In contrast, the quenching mechanism at a low [DAPI]/[DNA] ratios was found to be purely static. The static quenching constant decreased linearly with respect to the [DAPI]/[DNA] ratio. Decrease in quenching efficiency can be explained by the association constant of [Ru(phen)2DPPZ]2+ to DNA while being within a quenchable distance from a DAPI molecule. [Copyright &y& Elsevier]

The time-dependent binding mode of a porphyrin dimer to poly[d(G-C)2] and poly[d(A-T)2] was investigated by spectroscopic methods including absorption and circular and linear dichroism (CD and LD) spectroscopy. Immediately after mixing with poly[d(G-C)2], the porphyrin dimer exhibited red-shift and hypochromism in the absorption spectrum and negative CD and LD spectra. With further red-shift in absorption, the CD and LD magnitude in the Soret region became increasingly negative over time. After it was stabilized, the magnitude of the reduced LD (LDr) in the Soret region was larger than that in the DNA absorption region, indicating that the second porphyrin was also intercalated. Following the rapid intercalation of the first porphyrin, the very slow intercalation of the second followed with first-order kinetics. In the poly[d(A-T)2] case, a bisignate CD spectrum was observed in the Soret region suggesting stacking of the porphyrins. The small alteration in the CD spectrum and increased absorbance, which followed the initial rapid spectral change, was of the second order. This alteration in the spectral properties was attributed to the conformational change of poly[d(A-T)2] near the binding site because the overall shape of the CD spectrum was conserved in spite of the changes in the absorption spectrum.