scholarly journals Photoprotective Activity of Lichen Extracts and Isolated Compounds in Parmotrema Tinctorum

2021 ◽  
Vol 11 (5) ◽  
pp. 12653-12661

Lichens are an excellent source for the discovery and development of new photoprotective compounds. However, investigation on their bioactivities remains limited, especially in Vietnam. In this study, six lichen extracts (Parmotrema poolii, P. sancti-angelii, P. tinctorum, Usnea baileyi, U. pulvinulata, U. undulata) and five isolated compounds from commonly distributed species P. tinctorum (methyl β-orcinol carboxylate (1), atranorin (2), lecanorol (3), salazinic acid (4), 1β-acetoxyhopan-3β,22-diol (5)) have been screened in vitro for their photoprotective activity. The photoprotective potential was investigated by determination of their absolute (UV-PF, c, UVA-PF) and relative indexes (SUI, ISP). The structures of isolated compounds were elucidated by spectroscopic methods and confirmed by X-ray diffraction. The results showed that P. poolii, P. sancti-angelii, P. tinctorum, U. baileyi, U. undulata, and compounds of methyl β-orcinol carboxylate (1) and salazinic acid (4) acted as strict UVB filters, and their photoprotective activities are comparable to that of the commercial UVB filter (4-methylbenzylidene camphor). Meanwhile, U. pulvinulata acted as a UVA booster. Compound (3) presented characteristics of a UVA filter, (2) protected well from both UVA and UVB while (5) exhibited a weak photoprotective activity. For the first time, this work successfully extracted several highly potential solar photoprotective compounds from Vietnam's lichens.

2020 ◽  
Vol 17 (35) ◽  
pp. 303-314
Author(s):  
Marcelo Kehl; ; ; ; DE SOUZA ◽  
Marcos Antônio KLUNK ◽  
Soyane Juceli Siqueira XAVIER ◽  
Mohuli DAS ◽  
Sudipta DASGUPTA

One of the main contaminants of kaolinite, the iron, directly impacts quality in its commercial value. The spectroscopic monitoring, measured the depth of absorption of kaolinite, is compared with the literature in order to identify possible contaminants. The occurrence of kaolinite is due to the formation of primary minerals after the partial release of cations and silicon. This clay-mineral has a simple shape, with variable crystallographic imperfections, especially in the presence of iron, which replaces aluminum in the mineral chain, causing various structural disorganizations. The extraction of industrial minerals combined with geological studies, allows the development of new sources of energy, such as clay minerals, in particular kaolinite. Depending on the origin of the kaolinites, the presence of iron oxides in its structure, Fe2O3 and FeO(OH), are common. By comparing the results of spectroscopy (X-ray fluorescence, X-ray diffraction, RAMAN) and imaging using SEM-EDS, it was possible to identify kaolinite, with a higher determination coefficient, when the proportion of kaolinite reaches 60% or more in the mix. Kaolinite can be identified and quantified with a high correlation in the mixture from the sample absorption. Thus, the method has great potential to assist in quantifying and, consequently, in discriminating the quality of kaolinite.


2019 ◽  
Vol 43 (9-10) ◽  
pp. 437-442 ◽  
Author(s):  
Shou De Xu ◽  
Xiang Hua Wu

A series of bimetallic dppfM(II) (dppf = 1,1’-bis (diphenyphosphino) ferrocene; M = Pt and Pd) dithiocarbamate complexes is synthesized and characterized by spectroscopic methods and single-crystal X-ray diffraction. Their antitumor activities in vitro are investigated by MTT assays against four cancer cell lines. The anticancer studies indicate most of the complexes display good to excellent antitumor activity. Remarkably, the platinum complex with a pyrrolidinyl substituent (3b) was identified as the most promising candidate due to its high potency and broad spectrum of activity.


2019 ◽  
Vol 23 (10) ◽  
pp. 1158-1165
Author(s):  
Vladimir A. D'yakonov ◽  
Gulnara N. Kadikova ◽  
Guzel F. Gazizullina ◽  
Lilya U. Dzhemileva ◽  
Artur R. Tulyabaev ◽  
...  

Triepoxides were synthesized for the first time in high yields (80-85%) by oxidation of substituted bicyclo[4.2.2]deca-2,4,7,9-tetraenes, bicyclo[4.2.2]deca-2,4,7-trienes, and tricyclo[9.4.2.02,10]heptadeca-2,12,14,16-tetraene with an excess of m-chloroperbenzoic acid. The structures of the epoxy derivatives were reliably proved using modern spectral methods and X-ray diffraction analysis. A high antitumor activity in vitro was found for triepoxides against the Jurkat, K562, U937 tumor cell lines and normal fibroblasts.


2013 ◽  
Vol 8 (11) ◽  
pp. 1934578X1300801
Author(s):  
Tzu-Rong Su ◽  
Kai-Ju Liang ◽  
Michael Y. Chiang ◽  
Mei-Chin Lu ◽  
Yu-Jen Wu ◽  
...  

One new 5α,8α-epidioxysterol, 3-acetylaxinysterol (1), along with one known sterol, axinysterol (2), were isolated from a Formosan sponge, Axinyssa sp.. The structures of the compounds were determined by spectroscopic methods and the absolute configuration of 2 was further confirmed by single-crystal X-ray diffraction analysis for the first time. Compound 2 exhibited significant cytotoxicity against K562 and Molt 4 cancer cell lines.


2020 ◽  
Vol 17 ◽  
Author(s):  
Lima Rodrigues ◽  
Supriya Tilvi ◽  
Michelle S. Fernandes ◽  
Sarvesh S. Harmalkar ◽  
Santosh G. Tilve ◽  
...  

: The extract of marine green algae Enteromorpha sp. was evaluated in vitro for inhibitory activity against mushroom tyrosinase enzyme. The principle active agents i.e. coumarin; 4-hydroxycoumarin (1) and two sterols; ergosta-5,7,22- trien-3β-ol (2) & ergosterol peroxide (3) were isolated for the first time, from a crude methanol extract of Enteromorpha sp. showing anti-tyrosinase activity. Their structures were elucidated by IR, extensive NMR spectroscopy, LC-ESI-MS, Single crystal X-ray diffraction techniques. Thus, Enteromorpha sp. can be an alternative edible anti-tyrosinase agent.


Nanomaterials ◽  
2018 ◽  
Vol 8 (7) ◽  
pp. 539 ◽  
Author(s):  
Fozia Shaheen ◽  
Muhammad Aziz ◽  
Mahvish Fatima ◽  
Muhammad Khan ◽  
Faisal Ahmed ◽  
...  

Graphene-based materials have attracted considerable interest owing to their distinctive characteristics, such as their biocompatibility in terms of both their physical and intrinsic chemical properties. The use of nanomaterials with graphene as a biocompatible agent has increased due to an uptick in dedication from biomedical investigators. Here, GO-ZnO was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), ultraviolet-visible (UV-Vis) spectroscopy, energy dispersive X-ray analysis (EDAX), and Raman spectroscopy for structural, morphological, and elemental analysis. The toxic extent of GO-ZnO was noted by a methyl-thiazole-tetrazolium (MTT), while cellular morphology was observed towards the MCF-7 cells using an inverted microscope at magnification 40×. The cytotoxic effect of GO-ZnO investigated the cell viability reduction in a dose-dependent manner, as well as prompted the cell demise/destruction in an apoptotic way. Moreover, statistical analysis was performed on the experimental outcomes, with p-values < 0.05 kept as significant to elucidate the results. The generation of reactive oxygen species (ROS) demonstrated the potential applicability of graphene in tumor treatment. These key results attest to the efficacy of GO-ZnO nanocomposites as a substantial candidate for breast malignancy treatment.


2021 ◽  
Vol 54 (1) ◽  
pp. 180-194
Author(s):  
Dmitry Roshchupkin ◽  
Luc Ortega ◽  
Olga Plotitcyna ◽  
Ivo Zizak ◽  
Simone Vadilonga ◽  
...  

The possibilities are presented of X-ray diffraction methods for studying the propagation of surface acoustic waves (SAWs) in solids, including diffraction under total external reflection conditions and Bragg diffraction, using acoustically modulated X-ray multilayer mirrors and crystals. SAW propagation was studied using both meridional and sagittal diffraction geometries where the SAW wavevectors and X-ray photons are collinear or perpendicular, respectively. SAW propagation in a crystal leads to sinusoidal modulation of the crystal lattice and the appearance of diffraction satellites on the rocking curve. The intensities and angular positions of these diffraction satellites are determined by the SAW wavelength, amplitude and attenuation. Therefore, diffraction methods allow the analysis of the SAW propagation process and determination of SAW parameters. The influence of X-ray energy on diffraction by acoustically modulated crystals is studied for the first time. It is shown that changes in the X-ray energy can change the angular region where diffraction satellites exist under conditions of total external reflection. By contrast, in the Bragg diffraction region changes in the X-ray photon energy lead to changes in the X-ray penetration depth into the crystal and redistribution of the diffracted intensity among diffraction satellites, but do not change the angular divergence between diffraction satellites on the rocking curve. It is also shown that, in X-ray diffraction on acoustically modulated crystals on a number of successive reflections, a decrease in interplanar spacing leads to an increase in the number of diffraction satellites and a redistribution of diffracted radiation between them.


2014 ◽  
Vol 577 ◽  
pp. 771-776
Author(s):  
Yuan Liu ◽  
Xin Wen Duan ◽  
Cheng Xi Hu ◽  
Hao Sun ◽  
Jian Rui Zhu

Comparison research for XRD patterns between Modulus Maximum denoising (marked MJ) and thresholding denoising (marked Thr) all based on wavelet analysis, and the Savitzky-Golay filter (marked SG), as well as variation of denoising effect with required parameters of SG method, was investigated for the first time. The results showed that the Thr method exhibited a good smoothing effect for mineral XRD patterns with sharp peaks, and the MJ method was more suitable for plant-based XRD patterns with broad dispersive peaks. Although the SG method with the optimized parameters possessed a higher denoising property for both the two kinds of patterns, the determination of optimized parameters was hard and needed to be specified by users.


Author(s):  
R. J. Narconis ◽  
G. L. Johnson

Analysis of the constituents of renal and biliary calculi may be of help in the management of patients with calculous disease. Several methods of analysis are available for identifying these constituents. Most common are chemical methods, optical crystallography, x-ray diffraction, and infrared spectroscopy. The application of a SEM with x-ray analysis capabilities should be considered as an additional alternative.A scanning electron microscope equipped with an x-ray “mapping” attachment offers an additional dimension in its ability to locate elemental constituents geographically, and thus, provide a clue in determination of possible metabolic etiology in calculus formation. The ability of this method to give an undisturbed view of adjacent layers of elements in their natural state is of advantage in determining the sequence of formation of subsequent layers of chemical constituents.


Sign in / Sign up

Export Citation Format

Share Document