Gallic Acid Monohydrate Research Articles

Hydrogen bonding and Hirshfeld surface analysis of gallic acid and its monohydrate based on terahertz spectroscopy

The terahertz (THz) spectroscopy of gallic acid (GA) and gallic acid monohydrate (GAMD) in the frequency range of 0.2–3.0 THz were investigated using terahertz time-domain spectroscopy (THz-TDS) system. The THz absorption spectrum of GAMD exhibited a red-shift compared to that of GA. To resolve the absorption spectra of the two substances, density functional theory (DFT) was employed to calculate and simulate the theoretical spectra of the two substances in this frequency range, while the vibration mode automatic relevance determination (VMARD) method combined with GaussView and VMD software was utilized to determine the origin of each absorption peak. Additionally, Hirshfeld surface analysis and the Atoms-in-Molecules (AIM) topological analysis were conducted to explore the intermolecular interactions between GA and GAMD. The results revealed that the characteristic absorption peaks of both GA and GAMD are attributed to overall atomic and molecular motions, whereas those of GAMD are accompanied by water molecule translation. Furthermore, H…O/O…H hydrogen bonding was identified as the main contributor to the interaction between GA and GAMD. The addition of water molecules led to differentiation in the position and strength of intermolecular interactions; specifically, hydrogen bonding in GA primarily involved the carboxyl group with the hydroxyl group, while hydrogen bonding in GAMD occurred between the water molecule and the hydroxyl group of the central molecule.

Crystal engineering of the seventh polymorph of gallic acid monohydrate: a structural comparative study with previous polymorphs

Crystal engineering of the seventh polymorph of gallic acid monohydrate: a structural comparative study with previous polymorphs

Effective anti-inflammatory phenolic compounds from dandelion: identification and mechanistic insights using UHPLC-ESI-MS/MS, fluorescence quenching and anisotropy, molecular docking and dynamics simulation

This novel study identifies the effective anti-inflammatory phenolic compounds in dandelion and provides mechanistic insights into their interactions with receptor proteins (toll‐like receptor 4, TLR4; co‐receptor myeloid differentiation protein-2, MD-2) using UHPLC-ESI-MS/MS, lipopolysaccharide (LPS)-stimulated THP-1 cell line, fluorescence quenching and anisotropy, molecular docking (single ligand and multi-ligand docking) and molecular dynamics simulation. A 50 % aqueous methanol extract had a greater anti-inflammatory effect and higher chicoric acid content, compared with the 100 % water and 100 % methanol extracts. Chicoric acid, chlorogenic acid, methylophiopogonone A, caffeic acid, gallic acid monohydrate and 4'-O-demethylbroussonin A had relatively high binding energies and contents in all extracts. Chicoric acid competed with chlorogenic acid, 4'-O-demethylbroussonin A and quercetin for MD-2. Among dandelion’s phenolics, chicoric acid most effectively hindered TLR4-MD-2 complex formation, with a quenching constant of 0.62 × 106 L/mol for MD-2 or TLR4 at 320 K, and binding energies of –6.87 and –5.97 kcal/mol, respectively, for MD-2 and TLR4.

Six novel multicomponent systems of theobromine with carboxylic acids: crystallographic structures, solubility determination and DFT calculations

Cocrystals of theobromine with carboxylic acids prepared by ball milling and solution method: crystallographic structures and solubility determination.

Crystal engineering of a new pharmaceutical polymorph of gallic acid monohydrate: a structural comparative study and chemical computational quantum investigations

Exploiting new polymorphs of active pharmaceutical ingredients (APIs) has a significant role in the development of new processes for the pharmaceutical industry.

Addition of Gallic Acid Overcomes Resistance to Cisplatin in Ovarian Cancer Cell Lines.

Ovarian cancer is one of the leading causes of cancer-related mortality in women, and is often associated with drug resistance. Therefore, finding effective drugs, including naturally derived compounds, is urgently needed. Herein, we aimed to test the anti-cancer potential of gallic acid monohydrate (GA) and its congeners on cisplatin-sensitive (A2780S), and resistant (A2780CP) ovarian cancer and normal ovarian (HOSE6-3) cell lines. Cytotoxicity was assessed by AlamarBlue and CCK08 assays by exposing cells to different concentrations of cisplatin (0-21µg/mL), GA and its congeners (0-100µg/mL), and a combination of GA and cisplatin. Apoptosis was estimated by Hoechst stain and monitoring the relative RNA expression of the apoptotic effector caspase-3 using qRT-PCR. GA decreased cell viability in a concentration-dependent manner in all cell lines, with an IC50 of 19.39µg/mL (A2780S), 35.59 µg/mL (A2780CP), and 49.32µg/mL (HOSE6-3). GA displayed higher cytotoxicity than its congeners. An apoptotic rate estimation of approximately 20% and 30% was obtained in A2780S and A2780CP. While the cytotoxicity observed with cisplatin and GA was comparable, combining the two enhanced the cytotoxicity significantly, especially in the A2780CP cell line (p<0.05). These data suggest that GA may help overcome the resistance. Hence, the cytotoxic effects of GA, especially on chemo-resistant ovarian cancer cells merit further investigation.<br />.

Determination of some phenolic substances in six different populations of turkish hazel (Corylus colurna L.) leaves and comparison of phenolic fluctuation with water deficiency

Turkish hazel (Corylus colurna L.) is one of the naturally grown hazelnut species in Turkey. It can be easily separated from other hazel species with its thick single stem and tall appearance. It can be used in afforestation and erosion control studies due to low demand for habitat and strong root system. It contains substances with high medicinal value in its fruits and leaves. Hazel leaves have strong antioxidant activity due to their high phenolic content. Objective of the study was primarily to determine the individual phenolic constituents of six different population of Turkish Hazelnut and then to evaluate the effect of water deficiency stress generated by irrigation regime on phenolic constituents and photosystem II activity on these genotypes. Grafted plants were produced by taking scions from six different populations of Turkish Hazelnut (O&amp;#287;uzlar, Erenler, Merkeşler, Seben, Güney Felakettin and Pelitcik). The study was started when the grafted seedlings were 7 years old in greenhouse. During the experiment (June and July), two different levels of irrigation were applied (W1: the soil was fully irrigated to reach field capacity in each irrigation; W2: 50% reduction of W1 irrigation water). After the application of two different irrigation regimes, leaves were collected for each month, dried, extracted with methanol and then quantitatively analyzed and compared for individual phenolic constituents (gallic acid monohydrate, caffeic acid, rutin hydrate, luteolin-7-O-&amp;#946;-D glucoside, kaempferol, rosmarinic acid, myricetin, quercetin, coumarin and apigenin) by using high performance liquid chromatography (HPLC) coupled with a diode array detector (DAD). Generally, rutin, kaempferol and luteolin were dominant individual phenols in methanol extracts of Turkish hazelnut leaves. Pelitcik population was noticeable source of rutin and kaempferol in June, and the halved irrigation regime significantly increased the levels of both phenols in July. Similarly, the highest total phenolic content was observed in the Pelitcik population in June and the halved irrigation regime significantly increased the total phenolic content in both months in this population. It was also determined to what extent water deficiency physiologically affects the quantum efficiency (Fv/Fm) of photosystem II activity through chlorophyll fluorescence technique in hazelnut leaves. Generally, Fv/Fm value decreased with water deficiency. This study showed that water deficiency stress generally caused an increase in phenolic constituents in Turkish Hazel leaves and they may be proper natural sources of phenolic constituents with abiotic stress applications in pharmaceutical and food industry.

PARAFAC modeling of dandelion phenolic compound fluorescence relation to antioxidant properties

The phenolic compounds in dandelion were extracted using different ethanol percentage solutions, identified with HPLC-MS, and their scavenging capabilities of DPPH, ABTS and OH radicals were determined. Then the excitation-emission matrix fluorescence spectroscopy coupled with parallel factor analysis (PARAFAC) was conveyed to analyze the relationship between phenolics, components scores of PARAFAC model and antioxidant capacities, based on linear regression method. The results showed that the relative content of chicoric acid, esculetin, caffeic acid, gallic acid monohydrate, eupatilin, caffeic acid-3-glucoside, corchorifatty acid F, and luteolin was higher than 0.5%, and the extraction solutions with 100% and 75% water had a better scavenging capacity of DPPH, ABTS and OH radicals. Two components PARAFAC model was identified with the comparatively higher sum of squares, core consistency values, and lower interactions numbers, and the established equations indicated the component scores had a linear regression relationship with antioxidant capacities of DPPH, and ABTS. The paper was proposed for the first time that the component scores of PARAFAC model might be treated as a useful indication for antioxidant capacity evaluation.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11694-022-01389-z.

Evaluation of some traditional medicinal plants: phytochemical profile, antibacterial and antioxidant potentials

Bioassays provide an authentication of the traditional knowledge of medicinal plants. Antibacterial, antioxidant and phenolic content of nine medicinal plants (Achillea millefolium, Prunella vulgaris, P. laciniata, Lythrum salicaria, Epilobium angustifolium, E. hirsutum, Pedicularis comosa, Agrimonia eupatoria and Verbena officinalis) were investigated in connection with folkloric usages. Aerial parts of nine plant species were extracted with water and methanol (MeOH). Disc diffusion method was performed to evaluate the antibacterial activity of the extracts against ten pathogenic bacteria. Antioxidant activity was determined by using 2,2-diphenyl-1- picrylhydrazil (DPPH) radical photometric assay. Total phenolic and flavonoid content were investigated by using Folin-Ciocaltaeu and aluminum chloride (AlCl3) colorimetric method, respectively. Quantitative analysis of phenolic constituents of nine plants species were performed by high performance liquid chromatography-diode array detector (HPLC-DAD) via chosen ten phenolic standards (gallic acid monohydrate, caffeic acid, rutin hydrate, luteolin-7-O-β-D glucoside, kaempferol, rosmarinic acid, myricetin, quercetin, coumarin and apigenin). E. hirsutum showed the best antibacterial activity against gram-positive bacteria (S auerus, S. epidermidis and S. pyogenes). L. salicaria also demonstrated strong and broad spectrum antibacterial activity. P. laciniata, L. salicaria and E. angustifolium showed potent antioxidant activity. The highest phenolic and flavonoid content was observed with E. hirsutum and A. millefolium, respectively. L. salicaria also had very high amount of total phenol and flavonoid content. HPLC-DAD analysis displayed that P. laciniata and A. eupatoria were the best sources of rosmarinic acid. Furthermore, V. officinalis and P. vulgaris also had remarkable amount of rutin. This study revealed the scientific rationale behind the traditional knowledge of the tested plants. Consistent with traditional usages, the most prominent plants were L. salicaria, E. hirsutum and E. angustifolium in regard to strong antibacterial and antioxidant potentials. These plants may be proper natural sources with potential applications in pharmaceutical and food industry.

Insight into an Oxidative DNA-Cleaving DNAzyme: Multiple Cofactors, the Catalytic Core Map and a Highly Efficient Variant.

SummaryAn oxidative DNA-cleaving DNAzyme (PL) employs a double-cofactor model “X/Cu2+” for catalysis. Herein, we verified that reduced nicotinamide adenine dinucleotide (NADH), flavin mononucleotide, cysteine, dithiothreitol, catechol, resorcinol, hydroquinone, phloroglucinol, o-phenylenediamine, 3,3′,5,5'-tetramethylbenzidine, and hydroxylamine acted as cofactor X. According to their structural similarities or fluorescence property, we further confirmed that reduced nicotinamide adenine dinucleotide phosphate (NADPH), 2-mercaptoethanol, dopamine, chlorogenic acid, resveratrol, and 5-carboxyfluorescein also functioned as cofactor X. Superoxide anions might be the commonality behind these cofactors. We subsequently determined the conservative change of individual nucleotides in the catalytic core under four different cofactor X. The nucleotides A4 and C5 are highly conserved, whereas the conservative levels of other nucleotides are dependent on the types of cofactor X. Moreover, we observed that the minor change in the PL's secondary structure affects electrophoretic mobility. Finally, we characterized a highly efficient variant T3G and converted its double-cofactor NADH/Cu2+ to sole-cofactor NADH.

A novel aqueous gallic acid-based natural deep eutectic solvent for delignification of hybrid poplar and enhanced enzymatic hydrolysis of treated pulp

Natural deep eutectic solvent (NADES) emerged as a promising solvent used for lignocellulosic biomass dissolution and lignin separation. In this work, we prepared an aqueous NADES from choline chloride and a type of aromatic hydrogen bond donor, gallic acid-monohydrate, according to the possible solute-solvent interactions where phenyl-based NADES possessed favorite interactions with lignin aromatic compounds. Aqueous gallic acid-based NADES induced a high lignin removal (50.0%) of poplar and enhancement of enzymatic hydrolysis yield of treated pulp (69.1%). Presence of water aided in decreasing NADES viscosity and improving mass transfer. Various characterization approaches of extracted lignin were employed to investigate changes of molecular weights, types and amounts of hydroxyl groups and crucial linkages. The aqueous gallic acid-based NADES exploited in this work exhibited desirable delignification performance. Formation of considerable hydrogen bonds and hydrophobic interactions between the aromatic gallic acid-based NADES and lignin contributed to the reduced re-aggregation and condensation of separated lignin fragments.

Electrochemical performance enhancement of high mass loading H-RuO2NPs electrode and aqueous symmetrical supercapacitor in the neutral electrolyte

Abstract In this work, high water content hydrous ruthenium oxide nanoparticles (H-RuO2NPs) were synthesized using gallic acid monohydrate as a reducing agent. X-ray diffraction and transmission electron microscopy results confirmed the formation of irregular shape H-RuO2NPs with an average size of 5 nm. The thermogravimetric study showed that the synthesized H-RuO2NPs content more than 70 % of water which makes it specifically suitable for the electrochemical application. Moreover, it was observed that increasing the mass loading of synthesized H-RuO2NPs from 0.5 mg cm−2 to 8 mg cm−2, the specific capacitance decreased from 676 to 217 Fg −1 at a scan rate of 5 mVs−1 in 1 M Na2SO4 electrolyte. Furthermore, the aqueous symmetrical supercapacitor with a total mass loading of 16 mg cm−2 exhibited a specific capacitance of 62 Fg −1 at a scan rate of 1 mVs−1 and the specific capacitance retention rate of 91.4 % was observed after 5000 cycles at a current density of 5 Ag−1.

Room-temperature synthesis of tin oxide nanoparticles using gallic acid monohydrate for symmetrical supercapacitor application

Tin oxide (SnO2) nanoparticles were synthesized using gallic acid monohydrate as a reducing agent via precipitation method at room temperature. The synthesized SnO2 nanoparticles (S-SnO2NPs) were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Energy dispersive x-ray (EDX) and Field emission gun scanning electron microscope (FEG-SEM). The results showed the formation of a tetragonal rutile crystal of spherical shape SnO2 nanoparticles with an average size of 20.40 nm. XPS analysis confirmed the oxidation state of Sn4+ with an energy gap of 8.5 eV. The electrochemical properties of S-SnO2NPs were coated on the electrochemically treated carbon cloth (S-SnO2NPs@ETCC) electrode were compared with the commercial SnO2 nanoparticles (C-SnO2NPs@ETCC) electrode. The electrochemical measurement displayed maximum specific capacitance of 523 F/g and 482 F/g for S-SnO2NPs@ETCC and C-SnO2NPs@ETCC electrodes at a scan rate of 5 mV/s in 1 M H2SO4 electrolyte, respectively. Further, the assembled symmetrical supercapacitor (SS) exhibited a specific capacitance of 156 F/g at a scan rate of 5 mV/s and a capacitance retention rate of 94.7% after 5000 cycles at a current density of 20 A/g for total mass loading of 10 mg cm−2 in hydrogel polymer electrolyte (PVA-H2SO4).

Enhancement of electrochemical properties of hydrous ruthenium oxide nanoparticles coated on chemically activated carbon cloth for solid-state symmetrical supercapacitor application

Electrochemical performance of bare carbon cloth (BCC) and chemically activated carbon cloth (CACC) as current collectors were studied for supercapacitor applications. The prepared hydrous ruthenium oxide nanoparticles (H–RuO2NPs) using gallic acid monohydrate coated on both BCC and CACC and employed as pseudocapacitive electrodes in aqueous neutral (1 M Na2SO4) electrolyte. The specific capacitance obtained for H–RuO2NPs coated on CACC (H–RuO2NPs@CACC) using constant current charge-discharge measurements was 837 F g−1 at a current density of 2 A g−1 which was 3.87 times higher than the H–RuO2NPs coated on BCC (H–RuO2NPs@BCC). Moreover, the capacitance retention rate for H–RuO2NPs@CACC and H–RuO2NPs@BCC was 97.54% and 95.8% after 5000 cycles at 20 Ag-1 respectively. Furthermore, the symmetrical supercapacitor (SS) fabricated using H–RuO2NPs@CACC electrodes delivers the capacitance up to 796 Fg- 1 at 2 mVs−1 with capacitance retention of 91.8% after 5000 cycles at 10 Ag-1 for total mass loading of 10 mg cm−2 in hydrogel polymer electrolyte (PVA- Na2SO4). The energy density of SS was 156 Wh kg−1 at a current density of 5 A g−1. The obtained results of SS suggest that the H–RuO2NPs@CACC electrode can be utilized for a high-performance energy storage device.

Investigation into structure and dehydration dynamic of gallic acid monohydrate: A Raman spectroscopic study

The dehydration process of gallic acid monohydrate was carried out by heating method and characterized using Raman spectroscopic technique. Density functional theory calculation with B3LYP function is applied to simulate optimized structures and vibrational frequencies of anhydrous gallic acid and its corresponding monohydrated form. Different vibrational modes are assigned by comparison between experimental and theoretical Raman spectra of above two polymorphs. Raman spectra show that vibrational modes of the monohydrate are distinctively different from those of anhydrous one. Meanwhile, the dynamic information about dehydration process of gallic acid monohydrate could also be observed and monitored directly with the help of Raman spectral analysis. The decay rate of the characteristic band from gallic acid monohydrate and the growth rate of anhydrous one are pretty consistent with each other. It indicates that there is no intermediate present during the dehydration process of gallic acid monohydrate. The results could offer us benchmark works for identifying both anhydrous and hydrated pharmaceutical compounds, characterizing their corresponding molecular conformation within various crystalline forms, and also providing useful information about the process of dehydration dynamic at the microscopic molecular level.

Comparative Pharmacokinetics of Gallic Acid After Oral Administration of Gallic Acid Monohydrate in Normal and Isoproterenol-Induced Myocardial Infarcted Rats.

Gallic acid (GA) is a polyphenolic natural product widely distributed in food, beverage, and traditional Chinese herbs with beneficial effects on the cardiovascular system. In this research, a comparative study was conducted to investigate the possible difference of pharmacokinetic process in normal and isoproterenol-induced myocardial infarcted rats after oral administration of GA monohydrate with the dose of 50 and 100 mg/kg, respectively. Quantification of GA in rat plasma was achieved by using a simple and rapid high-performance liquid chromatographic method. The results revealed that pharmacokinetics of GA were greatly different between normal and pathological state. GA exhibited slower absorption into the bloodstream, and yielded 1.7-fold (50 mg/kg GA) and 1.3-fold (100 mg/kg GA) less values of area under concentration–time curve as well as 2.5-fold lower of maximum blood concentration (Cmax) in MI rats than those in normal rats. In addition, significant prolonged T1/2 and MRT as well as decreased CL were also registered in MI rats. Our findings suggest that myocardial infarction could alter the pharmacokinetic process of GA, and thus the potential pharmacokinetic differences of herbal preparations (or dietary nutrition) containing GA between normal and pathological conditions should be brought to the forefront seriously in clinical practice.

Polyphenols-rich extract from Pleurotus eryngii with growth inhibitory of HCT116 colon cancer cells and anti-inflammatory function in RAW264.7 cells.

Edible mushrooms are rich sources of bioactive components. In this study, a polyphenol-rich extract, designated as PPEP, was isolated from an edible mushroom, Pleurotus eryngii. Using ultra high performance liquid chromatograph combined with triple time-of-flight mass spectrometry (UPLC-TOF/MS/MS), gallic acid monohydrate, 3-(3,4-dihydroxyphenyl)-propionic acid, methyl gallate, syringic acid, ellagic acid and catechin were identified in PPEP. This phenolic-rich extract PPEP exhibited anti-inflammatory effect in lipopolysaccharide-stimulated RAW264.7 macrophages by inhibiting the overproduction of pro-inflammatory mediators including nitric oxide (NO) and reactive oxygen species (ROS). It was demonstrated that the anti-inflammatory effects of PPEP were associated with the inhibition of iNOS expression, suppression of p-IκB protein expression and inhibition of NF-κB and IκB mRNA expression. Next, the inhibitory effect of PPEP against human colon cancer cells was also determined. PPEP suppressed cell proliferation of human colon cancer HCT116 cells in a dose- and time-dependent fashion, while it showed no inhibitory effect on normal human colonic myofibroblasts CCD-18Co cells at the same tested concentrations (0-200 μg mL-1). Moreover, PPEP induced cell cycle arrest and led to extensive cellular apoptosis in human colon cancer cells, which was associated with the downregulation of cell cycle-related signaling protein, e.g. cyclin B and cyclin E, and the upregulation of apoptosis-related signaling protein caspase-3 and cleaved caspase-3. Overall, our results provided a basis for using PPEP as a promising preventive agent against inflammatory disease and colon cancer.

Synthesis, structure and characterization of a hybrid centrosymmetric material (4-dimethylaminopyridinium nitrate gallic acid monohydrate) well-designed for non-linear optics

Hybrid material: 4-Dimethylaminopyridinium nitrate gallic acid monohydrate abbreviated DNGA monohydrate has been successfully synthesized by slow evaporation method at room temperature. X-ray diffraction (XRD) on a single crystal showed that the latter was crystallized in P-1 space group. Likewise, thermal analyses demonstrated the stability of our crystal up to 80 °C. Besides, the analysis of the infrared spectrum (FTIR), allowed us to confirm the presence of the different groups present in the structure. Furthermore, by studying the UV–Visible spectrum, the transparency of our crystal was proven. Despite the fact that of having a centrosymmetric structure, the nonlinear optical properties of our single crystal, which was tested by Kurtz-Perry technique, proved that its second harmonic generation efficiency was 1.22 times more than that of KDP (potassium dihydrogen phosphate) single crystal. This nonlinear optical behavior of the studied compound was also determined through the calculations of polarizability and first hyperpolarizability values.

Terahertz spectroscopic investigation of gallic acid and its monohydrate

The low-frequency spectra of gallic acid (GA) and its monohydrate were investigated by terahertz time-domain spectroscopy (THz-TDS) in the range of 0.5 to 4.5THz. The dehydration process of GA monohydrate was monitored on-line. The kinetic mechanism of the dehydration process was analyzed depending on the THz spectral change at different temperatures. The results indicate that the diffusion of water molecule dominates the speed of the entire dehydration process. Solid-state density functional theory (DFT) calculations of the vibrational modes of both GA and its monohydrate were performed based on their crystalline structures for better interpreting the experimental THz spectra. The results demonstrate that the characterized features of GA mainly originate from the collective vibrations of molecules. And the interactions between GA and water molecules are responsible for THz fingerprint of GA monohydrate. Multi-techniques including differential scanning calorimetry and thermogravimetry (DSC-TG) and powder X-ray diffraction (PXRD) were also carried out to further investigate GA and its monohydrate.

A crystal structure prediction enigma solved: the gallic acid monohydrate system - surprises at 10 K.

The seemingly unpredictable structure of gallic acid monohydrate form IV has been investigated using accurate X-ray diffraction measurements at temperatures of 10 and 123 K. The measurements demonstrate that the structure is commensurately modulated at 10 K and disordered at higher temperatures. Aided by charge-density modeling and periodic DFT calculations we show that the disorder gives a substantial stabilization of the structure.