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Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7219
Author(s):  
Tsvetomil Voyslavov ◽  
Elisaveta Mladenova ◽  
Ralitsa Balkanska

A new approach for the botanical origin determination of monofloral bee honey is developed. The methodology combines mineral content and physicochemical parameters determination with intelligent statistics such as self-organizing maps (SOMs). A total of 62 monofloral bee honey samples were analysed, including 31 linden, 14 rapeseed, 13 sunflower, and 4 acacia. All of them were harvested in 2018 and 2019 from trusted beekeepers, after confirming their botanical origin, using melissopalynological analysis. Nine physicochemical parameters were determined, including colour, water content, pH, electrical conductivity, hydroxymethylfurfural content, diastase activity, specific optical rotation, invertase activity, and proline. The content of thirty chemical elements (Ag, Al, As, B, Ba, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, In, K, Li, Mg, Mn, Na, Ni, P, Pb, Rb, S, Se, Sr, Te, V, and Zn) was measured using ICP-OES, ICP-MS, and FAAS as instrumental techniques. The visualisation of the SOMs shows an excellent separation of honey samples in five well-defined clusters—linden, rapeseed, acacia, sunflower, and polyfloral honey—using the following set of 16 descriptors: diastase activity, hydroxymethylfurfural content, invertase activity, pH, specific optical rotation, water content, Al, B, Cr, Cs, K, Na, Ni, Rb, V, and Zn.


Toxins ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 812
Author(s):  
Marco Masi ◽  
Samaneh Bashiri ◽  
Alessio Cimmino ◽  
Zeinab Bahmani ◽  
Jafar Abdollahzadeh ◽  
...  

Biscogniauxia rosacearum, recognized for the first time as a pathogen involved in grapevine trunk diseases in Paveh (west of Iran) vineyards, produced meso-2,3-butanediol (1) as the only phytotoxin. Nectriapyrone (2), (3R)-5-methylmellein (3), (3R)-5-methyl-6-methoxymellein (4), and tyrosol (5) were instead produced as phytotoxins from a strain of the same fungus isolated from oak trees in Zagros forests of Gilan-e Gharb, Kermanshah Province. They were identified comparing their 1H and 13C NMR, ESIMS, and specific optical rotation data with those already reported in the literature. The phytotoxicity of metabolites (1–5) was estimated by leaf puncture assay on Quercus ilex L. and Hedera helix L., and by leaf absorption assay on grapevine (Vitis vinifera L.) at a concentration of 5 × 10−3 and 10−3 M. Tested on grapevine, meso-2,3-butanediol (1) and (3R)-5-methyl-6-methoxymellein (4) resulted to be the most phytotoxic compounds. On Q. ilex, nectriapyrone (2) and tyrosol (5) showed severe necrosis at the highest concentration while none of the compounds (1–5) was active on H. helix. Furthermore, the phytotoxicity of compounds 3 and 4 was also compared with that of some related natural melleins to perform a structure-activity relationship (SAR) study. The results of this study were also discussed.


2021 ◽  
Vol 12 ◽  
Author(s):  
Xiaoyan Pang ◽  
Weihao Chen ◽  
Xin Wang ◽  
Xuefeng Zhou ◽  
Bin Yang ◽  
...  

Three new tetramic acid derivatives (1–3) and a new polyketide (4) along with eight known compounds (5–12) were isolated from cultures of the deep-sea-derived fungus Penicillium sp. SCSIO06868. Four new structures were elucidated by analysis of one-dimensional/two-dimensional nuclear magnetic resonance (NMR) data and high-resolution electrospray ionization mass spectrometry. Their absolute configurations were established by X-ray crystallography analysis and comparison of the experimental and reported electronic circular dichroism (ECD) values or specific optical rotation. Compound 3 exhibited potent, selective inhibitory activities against Staphylococcus aureus and methicillin-resistant S. aureus with minimum inhibitory concentration values of both 2.5 μg/ml. Also, compound 3 showed weak antiviral activity against severe acute respiratory syndrome coronavirus 2 main protease, which was responsible for the coronavirus disease 2019 pandemic.


2021 ◽  
Vol 10 (3) ◽  
pp. 88-94
Author(s):  
E. V. Ignateva ◽  
I. V. Yartseva ◽  
Z. S. Shprakh ◽  
A. P. Bud'ko ◽  
L. V. Ektova ◽  
...  

Introduction. Indolocarbazole derivatives are of increasing scientific interest for practical oncology. A number of N-glycosides, indolo[2,3-a] carbazole under the laboratory code LCS, were synthesized in the laboratory of chemical synthesis of the National Medical Center of Oncology named after N.N. Blokhin. Currently, one of the most promising compounds in this class is LCS-1208, a representative of the arabinoside class of indolo [2,3-a]pyrrolo[3,4-c]carbazole-5,7-dione. According to the mechanism of biological action, LCS-1208 is a protein kinase C inhibitor and is of great interest for the treatment of malignant neoplasms.Aim. chemical and pharmaceutical standardization of the pharmaceutical substance LCS-1208.Materials and methods. Laboratory samples of pharmaceutical substance LCS-1208. Methods of investigation: gravimetry, spectrophotometry, polarimetry, high-performance liquid chromatography (HPLC), high-resolution nuclear magnetic resonance (NMR) spectroscopy and infrared (IR) spectroscopy.Results and discussion. The quality assessment of LCS-1208 was carried out according to the indicators adopted in the XIV edition of the State Pharmacopoeia of the Russian Federation for quality control of pharmaceutical substances. LCS-1208 - orange amorphous powder, odorless; soluble in dimethylsulfoxide (DMSO) and dimethylformamide (DMF); very slightly soluble in 95 % ethyl alcohol and practically insoluble in water. The authenticity of the substance is confirmed by NMR and IR spectra, as well as electronic absorption spectra. The values of the specific optical rotation of LCS-1208 (1 % solution in DMF) are placed in the range from +58° to +61°. All the studied samples of the substance were free of inorganic impurities, sulphate ash, heavy metals and contained no more than 1.0 % water, determined by the K. Fischer titration method. The content of possible related impurities in the substance LCS-1208 and the content of the main active substance were determined by HPLC. The studied laboratory series of the pharmaceutical substance LCS-1208 contained no more than 1.0 % of any single and no more than 3 % of the total unidentified impurities. The content of the main active substance was more than 97 %.Conclusion. As a result of the work carried out, quality criteria and parameters were selected and methods for their determination were developed, which allow to adequately assess the quality and standardness of the pharmaceutical substance LCS-1208.


Author(s):  
Yi-Jie Zhai ◽  
Jian-Nan Li ◽  
Yu-Qi Gao ◽  
Lin-Lin Gao ◽  
Da-Cheng Wang ◽  
...  

AbstractTwo new sterpurane sesquiterpenoids named sterpurol D (1) and sterpurol E (2), and one skeletally new sesquiterpene, cryptomaraone (3), bearing a 5,6-fused bicyclic ring system, along with five known ones, sterpurol A (4), sterpurol B (5), paneolilludinic Acid (6), murolane-2α, 9β-diol-3-ene (7) and (–)-10,11-dihydroxyfarnesol (8) were isolated from an endolichenic fungus Cryptomarasmius aucubae. The structures of the new compounds were elucidated by analysis of NMR spectroscopic spectra and HRESIMS data. The absolute configurations of 1 and 2 were established by spectroscopic data analysis and comparison of specific optical rotation, as well as the biosynthetic consideration. Additionally, compounds 1, 2, 4–6, and 8 showed significant nitric oxide (NO) production inhibition in Lipopolysaccharide (LPS)-induced BV-2 microglial cells with the IC50 values ranging from 9.06 to 14.81 μM. Graphic Abstract


Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 740
Author(s):  
Jociani Ascari ◽  
Marcos Felipe Maciel Pereira ◽  
Vinicius Monteiro Schaffka ◽  
Domingos Sávio Nunes ◽  
Cássia Gonçalves Magalhães ◽  
...  

The sesquiterpenes selina-1,3,7(11)-trien-8-one and oxidoselina-1,3,7(11)-trien-8-one were isolated from the essential oil of Eugenia uniflora L. leaves. The structures were elucidated using spectrometric methods (UV, GC–MS, NMR, and specific optical rotation). The relationship between antioxidant activity, as determined by DPPH assay, and the cytotoxic effect was evaluated using tumor cells, namely lung adenocarcinoma epithelial cells (A549) and human hepatoma carcinoma cells (HepG2), as well as a model of normal human lung fibroblast cells (IMR90). Both compounds did not show prominent free-radical scavenging activity according to DPPH assay, and did not inhibit lipid peroxidation in Wistar rat brain homogenate. The isolated compounds showed pro-oxidative effects and cytotoxicity in relation to the IMR90 cell line.


2020 ◽  
Vol 16 (9) ◽  
pp. 1421-1430
Author(s):  
Zidane Djelloul ◽  
Sid-Ahmed Benaoula ◽  
Abdeldjalil Daioui ◽  
Mohammed Z.E. El Mahi ◽  
Boumedien Meddah ◽  
...  

Background: Consumers have become aware that the industrial methods of honey production have greatly affected the environment and product quality. Today, they want a reorientation of these production modes to obtain healthy and natural organic products. Objective: This study is conducted to evaluate, for the first time in Algeria, the physicochemical composition of organic honey’s harvest in the organic- North West Algerian area. Methods: Twenty-four samples of organic honey were harvested according to the organic beekeeping rules, by selected volunteer beekeepers in organic regions and hives, and then, they were extracted by the traditional method. Physicochemical parameters, such as pH, free acidity, density, electrical conductivity, diastase activity, carbohydrates, hydroxyl methyl furfural (HMF), water content, ash, color intensity and specific optical rotation were evaluated. Results: Mean values obtained for physicochemical parameters were: pH as 3-4.8, electrical conductivity as 0.123-1.180 mS/cm, free acid as 8-30 mEq/kg, diastase activity as 8.02-40.54 (Shade units), carbohydrates as 60.21-77.07%, sucrose as 1.04-8.97%, HMF quality as 4.67-27.63 mg/kg, water content as 14.2-19.0%, ash as 0.09-0.86%, color intensity ABS450 as 288-1467 mAU, color intensity (Pfund scale) as 0.30-137.34 mm and specific optical rotation at (-16.1)-(-3.8). The analysis indicated that organic honey samples grown in selected sites of our local area are of good quality. All of the obtained values were within the limits imposed by the present legislation (Codex Alimentarius). Conclusion: Analyzed honey samples are characterized as biological products of excellent quality with interesting nutritional properties.


2020 ◽  
Vol 53 (5) ◽  
pp. 1257-1265
Author(s):  
Mykola Shopa ◽  
Yaroslav Shopa ◽  
Michael Shribak ◽  
Elena Kostenyukova ◽  
Igor Pritula ◽  
...  

Conoscopic interference patterns, channelled spectra and polarimetric techniques have been used for the characterization of pure and doped (with L-arginine amino acid) potassium dihydrogen phosphate (KDP) single crystals. Experimental polarimetric data have been obtained for the frequently used wavelength of 633 nm and for two close wavelengths of 532 and 543 nm in a high-accuracy dual-wavelength polarimeter. The measurement of eigenwave ellipticity in the [100] and [010] directions and between 295 and 340 K shows small differences in the absolute values of the specific optical rotations of KDP crystals doped with L-arginine in the range of 0.7–3.8 wt%. It is found that the gyration tensor component g 11, specific optical rotation and eigenwave ellipticity show different dispersion in the visible spectral region.


2020 ◽  
Author(s):  
Yi Zhang ◽  
Evgenia Glukhov ◽  
Haobin Yu ◽  
Lena Gerwick ◽  
Pieter Dorrestein ◽  
...  

<p>LC-MS<sup>2</sup>-based molecular networking using the Global Natural Products Social (GNPS) tool revealed a rich assortment of brominated compounds present in the antioxidant fraction of a red algal extract (<i>Ceramium</i> sp.) Further chemical investigation led to discovery of one monomeric bromophenol (lanosol isopropyl ether, <b>1</b>) and seven dimeric ones (bromourceolatols A-G, <b>2</b>-<b>8</b>), all of which are previously undescribed. Their structures were elucidated by extensive analysis of their spectroscopic data. Compounds <b>2</b>-<b>8 </b>were determined to be racemic trans-type isomers by NOESY, specific optical rotation, and ECD. Compounds <b>1</b> and <b>3</b> displayed antioxidant activity with their EC<sub>50</sub> of 44.4 and 47.0 μM, respectively, for scavenging DPPH free radicals while compounds <b>2</b> and <b>4</b> had approximate EC<sub>50</sub> values of ~ 64 μM. Furthermore, compounds <b>2</b>, <b>3</b>, and <b>7</b> exhibited relatively potent anti-inflammatory activity at 32 μM by quenching 97%, 47%, and 73% of nitric oxide induced by bacterial lipopolysaccharide in macrophage RAW264.7 cells, respectively.</p>


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