ABSTRACT
Sulfur compounds in fuel such as thiophene, benzothiophene and dibenzothiophene are the primary source of SO x emissions, leading to environmental pollution and acid rain. In this study, we synthesized a layered oxygen-doped graphitic carbon nitride (OCN) structure and integrated ZnO and TiO2 nanoparticles onto the OCN surface through a microwave-assisted sol-gel method. The X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) results confirmed a robust interaction between the ZnO and TiO2 nanoparticles and the oxygen-doped g-C3N4 (OCN) surface, as indicated by the formation of C-N-Ti and C-O-Ti bonds. This interaction notably improved the optoelectronic properties of the ZnO-TiO2/OCN composite, yielding increased visible light absorption, reduced charge recombination rate, and enhanced separation and transfer of photogenerated electron-hole pairs. The oxygen doping into the CN network could alter the band structure and expand the absorption range of visible light. The ZnO-TiO2/OCN photocatalyst demonstrated remarkable desulfurization capabilities, converting 99.19% of dibenzothiophene (DBT) to dibenzothiophene sulfone (DBT-O2) at 25 °C, and eliminating 92.13% of DBT from real-world fuel oil samples. We conducted in-depth analysis of the factors impacting the redox process of DBT, including the ZnO ratio, initial DBT concentration, catalyst dosage, stability, and O/S molar ratio. Radical trapping experiments established that ËO2 -, ËOH and h+ radicals significantly influence the reaction rate. The obtained results indicated that the ZnO-TiO2/OCN photocatalyst represents a promising tool for future fuel oil desulfurization applications.
ABSTRACT
Four undescribed spirostan glycosides, (25S)-5α-spirostan- 12-one-2α,3ß-diol-3-O-ß-D-glucopyranosyl-(1â4)-ß-D-galactopyranoside (1), (25S)-5α-spirostan-12-one-2α,3ß-diol-3-O-ß-D-galatopyranosyl-(1â2)-ß-D-glucopyranosyl- (1â4)-ß-D-galactopyranoside (2), (25S)-5α-spirostan-12-one-2α,3ß-diol-3-O-ß-D-glucopyranosyl-(1â2)-[ß-D-glucopyranosyl-(1â3)]-ß-D-glucopyranosyl-(1â4)-ß-D-galactopyranoside (3), and hecogenin 3-O-ß-D-glucopyranosyl-(1â3)-[ß-D-xylopyranosyl-(1â2)]-ß-D-glucopyranosyl-(1â4)-[α-L-rhamnopyranosyl-(1â2)]-ß-D-galactopyranoside (4), together with eleven known compounds (5-15) were isolated from the branches and leaves of Tribulus terrestris. Their chemical structures were established through spectroscopic methods, including HR-ESI-MS, 1D-, and 2D-NMR spectra. Preliminary biological evaluation on NO production inhibitory activity in LPS activated RAW 264.7â cells showed that compoundsâ 1-3, 5, and 6 had significant inhibitory effects with IC50 values ranging from 2.4 to 18.3â µM, compared to that of the positive control compound, dexamethazone (IC50 13.6â µM).
Subject(s)
Glycosides , Lipopolysaccharides , Nitric Oxide , Plant Leaves , Spirostans , Tribulus , Mice , Animals , RAW 264.7 Cells , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Tribulus/chemistry , Plant Leaves/chemistry , Glycosides/chemistry , Glycosides/pharmacology , Glycosides/isolation & purification , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/biosynthesis , Spirostans/chemistry , Spirostans/isolation & purification , Spirostans/pharmacology , Plant Stems/chemistry , Structure-Activity RelationshipABSTRACT
Phytochemical study on the methanol extract of the stem barks of Aphanamixis polystachya led to the isolation of four previously undescribed (1-4) and ten known compounds (5-14). Their chemical structures were elucidated to be 11-methoxysawaranospiroride C (1), 6α,9S,10,13-tetrahydroxymegastigmane-3-one (2), 11-hydroxyaphanamixin B (3), (2Z,6E,13E)-2,6,13-triene-11,15-dihydroxyphytanic acid (4), cinnacasside D (5), cinnacasside E (6), vilsonol F (7), (3S,5R,6S,7E,9R)-3,5,6,9-tetrahydroxy-7-en-megastigmane (8), (3S,5R,6R,7E,9R)-3,6,9,10-tetrahydroxy-7-en-megastigmane (9), citroside A (10), threo-1-(3,4,5-trimethoxyphenyl)-1,2,3-propanetriol (11), 3,4,5-trimethoxyphenyl-1-O-ß-D-glucopyranoside (12), p-coumaric acid (13), ferulic acid (14) by HR-ESI-MS, ECD, 1D-, and 2D-NMR spectra. Compounds 1, 3, 4, and 9 showed NO production inhibitory activity in LPS activated RAW 264.7 cells with IC50 values of 42.0, 67.9, 20.5, and 78.6â µM, respectively, while the remaining compounds were inactive with IC50 values over 100â µM.
Subject(s)
Lipopolysaccharides , Nitric Oxide , Plant Bark , Mice , RAW 264.7 Cells , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Animals , Plant Bark/chemistry , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/biosynthesis , Nitric Oxide/metabolism , Plant Stems/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Extracts/isolation & purification , Molecular Structure , Structure-Activity RelationshipABSTRACT
In this study, four undescribed bibenzyl derivatives (1-4), together with seven known compounds (5-11) were isolated from the aerial parts of Dendrobium officinale. Their chemical structures were determined to be (7'S,8'S) -9''-acetyldendrocandin U (1), (7'S,8'S) -4'-methoxydendrocandin T (2), (7'R,8'S) -dendrocandin B (3), (1S,2R) -5'''-methoxydendrofindlaphenol C (4) by analyzing of the spectroscopic data including HR-ESI-MS, 1D-, and 2D-NMR spectra. The absolute configurations of compounds 1-4 were determined by the electronic circular dichroism (ECD) spectra. Compounds 1-3, 5, 10 and 11 inhibited α-glucosidase with the IC50 values ranging from 56.3 to 165.3â µM, compounds 1-3, 5, 7-10 inhibited α-amylase with the IC50 values ranging from 65.2 to 177.6â µM.
Subject(s)
Dendrobium , Glycoside Hydrolase Inhibitors , Plant Components, Aerial , alpha-Amylases , alpha-Glucosidases , Dendrobium/chemistry , alpha-Amylases/antagonists & inhibitors , alpha-Amylases/metabolism , alpha-Glucosidases/metabolism , Glycoside Hydrolase Inhibitors/pharmacology , Glycoside Hydrolase Inhibitors/chemistry , Glycoside Hydrolase Inhibitors/isolation & purification , Plant Components, Aerial/chemistry , Stilbenes/chemistry , Stilbenes/pharmacology , Stilbenes/isolation & purification , Structure-Activity Relationship , Molecular Structure , Molecular ConformationABSTRACT
From the methanol extract of the Cryptolepis buchananii fruits, four undescribed pentacyclic triterpenene glycosides (1-4) and five known pentacyclic triterpenenes (5-9) were isolated. Their structures were determined to be uncargenin C 28-O-α-L-rhamnopyranosyl-(1â2)-ß-D-glucopyranosyl ester (1), 3-O-ß-D-glucopyranosyluncargenin C 28-O-α-L-rhamnopyranosyl-(1â2)-ß-D-glucopyranosyl ester (2), 3-O-ß-D-glucopyranosyl-(1â6)-ß-D-glucopyranosyl-6ß,23-dihydroxyursolic acid 28-O-α-L-rhamnopyranosyl-(1â2)-ß-D-glucopyranosyl ester (3), 3-O-ß-D-glucopyranosyl-(1â2)-ß-D-glucopyranosylasiatic acid 28-O-α-L-rhamnopyranosyl-(1â2)-ß-D-glucopyranosyl ester (4), asiatic acid (5), 2α,3ß,23-trihydroxyoleana-11,13(18)-dien-28-oic acid (6), arjunolic acid (7), 6ß-hydroxyarjunolic acid (8), and actinidic acid (9) based on analyses of their HR-ESI-MS, 1D and 2D NMR spectra. All the isolates showed significantly NO production inhibition in LPS-activated RAW264.7 cells with the IC50 values ranging from 18.79 to 37.57â µM, compared to that of the positive control compound, dexamethasone, which showed IC50 value of 14.05â µM.
Subject(s)
Saponins , Triterpenes , Cryptolepis , Esters , Fruit , Glycosides/pharmacology , Glycosides/chemistry , Lipopolysaccharides/pharmacology , Pentacyclic Triterpenes/pharmacology , Saponins/chemistry , Triterpenes/pharmacology , Triterpenes/chemistryABSTRACT
Four undescribed phenolic glycosides including three stilbene derivatives (1 and 3) and sodium salt of 3 (2), and a chalcone glycoside (4), together with thirteen known compounds (5-17) were isolated from the leaves of Syzygium attopeuense (Gagnep.) Merr. & L.M.Perry. Their chemical structures were elucidated to be (Z)-gaylussacin (1), 6''-O-galloylgaylussacin sodium salt (2), 6''-O-galloylgaylussacin (3), 4'-O-[ß-D-glucopyranosyl-(1â6)-glucopyranosyl]oxy-2'-hydroxy-6'-methoxydihydrochalcone (4), gaylussacin (5), pinosilvin 3-O-ß-D-glucopyranoside (6), myricetin-3-O-(2''-O-galloyl)-α-L-rhamnopyranoside (7), myricetin-3-O-(3''-O-galloyl)-α-L-rhamnopyranoside (8), myricetin-3-O-α-L-rhamnopyranoside (9), quercitrin (10), myricetin-3-O-ß-D-glucopyranoside (11), myricetin-3-O-ß-D-galactopyranoside (12), quercetin 3-O-α-L-arabinopyranoside (13), myricetin-3-O-2''-O-galloyl)-α-L-arabinopyranoside (14), (+)-gallocatechin (15), (-)-epigallocatechin (16), and 3,3',4'-trimethoxyellagic acid 4-O-ß-D-glucopyranoside (17) by the analysis of HR-ESI-MS, 1D and 2D NMR spectra in comparison with the previously reported data. Compounds 1-3, 5, and 6 significant inhibition of NO production in LPS-activated RAW264.7 cells, with IC50 values ranging from 18.37±1.38 to 35.12±2.53â µM, compared to a positive control (dexamethasone) with an IC50 value of 15.37±1.42â µM.
Subject(s)
Glycosides , Syzygium , Glycosides/pharmacology , Glycosides/chemistry , Nitric Oxide , Phenols/pharmacology , Sodium , Molecular StructureABSTRACT
Phytochemical investigation on the aerial parts of Elsholtzia blanda Benth. afforded four new oleuropeic acid derivatives (1-4), named as elsholblanosides A-D, respectively, together with 11 known compounds (5-15). Their structures were determined based on extensive analyses of HR-ESI-MS, 1D and 2D NMR, and ECD spectra. Compounds 1-4 and 14 showed moderate NO production inhibition in LPS-activated RAW264.7 cells with their IC50 values ranging from 23.2 to 86.33â µM, compared to that of the positive control compound, dexamethasone, IC50 value of 16.9â µM.
Subject(s)
Cyclohexanecarboxylic Acids , Lamiaceae , Animals , Mice , Lipopolysaccharides/pharmacology , Lamiaceae/chemistry , RAW 264.7 Cells , Molecular StructureABSTRACT
A new isopropyl chromone (1) and a new flavanone glucoside (2) together with eleven known compounds (3-13) were isolated from the leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry. Their structures were elucidated as 5,7-dihydroxy-2-isopropyl-6,8-dimethyl-4H-chromen-4-one (1), 5,7-dihydroxyflavanone 7-O-ß-D-(6''-O-galloylglucopyranoside) (2), strobopinin (3), demethoxymatteucinol (4), pinocembrin-7-O-ß-D-glucopyranoside (5), (2S)-hydroxynaringenin-7-O-ß-D-glucopyranoside (6), afzelin (7), quercetin (8), kaplanin (9), endoperoxide G3 (10), grasshopper (11), vomifoliol (12), litseagermacrane (13) by the analysis of HR-ESI-MS, NMR, and CD spectral data. Compounds 1, 2, 5, 6 and 10 inhibited NO production on LPS-activated RAW264.7 cells with IC50 values of 12.28±1.15, 8.52±1.62, 7.68±0.87, 9.67±0.57, and 6.69±0.34â µM, respectively, while the IC50 values of the other compounds ranging from 33.38±0.78 to 86.51±2.98â µM, compared to that of the positive control, NG -monomethyl-L-arginine acetate (L-NMMA) with an IC50 value of 32.50±1.00â µM.
Subject(s)
Flavanones , Syzygium , Chromones/pharmacology , Flavanones/pharmacology , Glucosides/pharmacology , Glucosides/chemistry , Molecular Structure , Nitric Oxide , Plant Extracts/pharmacology , Plant Extracts/chemistry , Syzygium/chemistryABSTRACT
Five new triterpenoid glycosides, named campetelosides A-E (1-5), together with three known compounds, chikusetsusaponin IVa (6), umbellatoside B (7), and silvioside E (8) were isolated from the leaves of Camellia petelotii (Merr.) Sealy. Their chemical structures were determined by interpretations of HR-ESI-MS and NMR spectra. In addition, compounds 1-8 were evaluated for their α-glucosidase inhibitory effects. Compounds 1-3 significantly showed α-glucosidase inhibitory activity with IC50 values of 166.7±6.0, 45.9±2.6, and 395.3±10.5â µM, respectively, compared to that of the positive control, acarbose, with an IC50 value of 200.4±10.5â µM.
Subject(s)
Camellia , Oleanolic Acid , Saponins , Triterpenes , Molecular Structure , alpha-Glucosidases , Triterpenes/pharmacology , Triterpenes/chemistry , Camellia/chemistry , Oleanolic Acid/pharmacology , Oleanolic Acid/chemistry , Saponins/pharmacology , Saponins/chemistryABSTRACT
In this paper, a novel bimetallic Fe-Cu metal-organic framework combined with 1,3,5-benzenetricarboxylic acid (Fe-Cu-BTC) are synthesized using hydrothermal reaction. The bimetallic Fe-Cu-BTC with high BET (1504 cm3 g-1) and high Langmuir surface area (1831 cm3 g-1) is composited by gold nanoparticles to improve the conductivity and to develop their synergistic effect. A novel bisphenol A (BPA) sensor was prepared by dropcasting Fe-Cu-BTC on glassy carbon electrodes (GCE) followed by AuNPs electrodeposition. The Fe-Cu-BTC framework were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy studies (TEM), FT-IR, BET measurements and EDX spectra. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were carried out for surveying the electrochemical properties of the sensors and for the quantification of BPA. Two linear ranges of BPA concentrations 0.1-1.0 µM and 1.0-18 µM with 18 nM limit of detection were obtained. The developed sensor was used to measure the concentration of BPA in samples extracted from rain coat with the recovery ranging from 85.70 to 103.23%.
ABSTRACT
A phytochemical investigation of Physalis minima led to the isolation of six withanolides, including withanolide E (1), withaperuvin C (2), 4ß-hydroxywithanolide E (3), 28-hydroxywithaperuvin C (4), physaperuvin G (5), and 4-deoxywithaperuvin (6). Their chemical structures were elucidated by 1 D-NMR and 2 D-NMR data, as well as comparison with the data reported in the literature. All isolated compounds were evaluated for their cytotoxic activity against HepG2, SK-LU-1, and MCF7 cancer cell lines. As the obtained results, compounds 1 and 3 displayed the strongest cytotoxicity against HepG2, SK-LU-1, and MCF7 cell lines with IC50 value ranging from 0.051 ± 0.004 to 0.86 ± 0.09 µg/mL.
Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Physalis/chemistry , Withanolides/chemistry , Cell Line, Tumor , Drug Screening Assays, Antitumor , Hep G2 Cells , Humans , MCF-7 Cells , Magnetic Resonance Spectroscopy , Molecular Structure , Plant Components, Aerial/chemistry , Plant Extracts/chemistry , Structure-Activity Relationship , Withanolides/pharmacologyABSTRACT
In the present work, we reported the fabrication of a novel electrochemical sensing platform to detect 2,4-dichlorophenol (2,4-DCP) by using a copper benzene-1,3,5-tricarboxylate-graphene oxide (Cu-BTC/GO) composite. The sensor was prepared by drop-casting Cu-BTC/GO suspension onto the electrode surface followed by electrochemical reduction, leading to the generation of an electrochemically reduced graphene oxide network (ErGO). By combining the large specific area of the Cu-BTC matrix with the electrical percolation from the graphene network, the number of accessible reaction sites was strongly increased, which consequently improved the detection performance. The electrochemical characteristics of the composite were revealed by cyclic voltammetry and electrochemical impedance spectroscopy. For the detection of 2,4-DCP, differential pulse voltammetry was used to emphasize the faradaic reaction related to the oxidation of the analyte. The results displayed a low detection limit (83 × 10-9 M) and a linear range from 1.5 × 10-6 M to 24 × 10-6 M alongside high reproducibility (RSD = 2.5% for eight independent sensors) and good stability. Importantly, the prepared sensors were sufficiently selective against interference from other pollutants in the same electrochemical window. Notably, the presented sensors have already proven their ability in detecting 2,4-DCP in real field samples with high accuracy (recovery range = 97.17-104.15%).
ABSTRACT
In the present work, we reported the simple way to fabricate an electrochemical sensing platform to detect Bisphenol A (BPA) using galvanostatic deposition of Au on a glassy carbon electrode covered by cetyltrimethylammonium bromide (CTAB). This material (CTAB) enhances the sensitivity of electrochemical sensors with respect to the detection of BPA. The electrochemical response of the modified GCE to BPA was investigated by cyclic voltammetry and differential pulse voltammetry. The results displayed a low detection limit (22 nm) and a linear range from 0.025 to 10 µm along side with high reproducibility (RSD = 4.9% for seven independent sensors). Importantly, the prepared sensors were selective enough against interferences with other pollutants in the same electrochemical window. Notably, the presented sensors have already proven their ability in detecting BPA in real plastic water drinking bottle samples with high accuracy (recovery range = 96.60%-102.82%) and it is in good agreement with fluorescence measurements.
ABSTRACT
Three new muurolane type sesquiterpene glycosides, named balanoindicosides A - C (1 - 3), were isolated from the whole plant of Balanophora fungosa subsp. indica using various chromatographic methods. Their structures were determined by extensive analysis of HR-ESI-MS and NMR spectroscopy. The stereochemistry of muurolane sesquiterpene backbone was demonstrated by NOESY analysis. Configuration of C-12 in compounds 2 and 3 could be distinguished by chemical shift value of C-14. Compounds 1-3 exhibited weak cytotoxic activity towards HepG-2, HL-60, LU-1, and MCF-7 cell lines.