LC/MS/MS Phenolic Profile, Antioxidant Capacity, Angiotensin-Converting Enzyme (ACE) and Glutathione S Transferase (GST) Inhibitory Properties of Ultrasound-Assisted Propolis Extracts.

Resinous beehive product propolis has many biological activities. It contains various aromatic substances that have great differences in their chemical composition depending on the natural flora. Thus, chemical characterization and biological properties of propolis samples is an important subject for the pharmaceutical industry. In this study, the propolis samples collected from three cities in Turkey were prepared as methanol (MEP), ethanol (EEP), chloroform (ChlEP), hexane (HxEP), and ethyl acetate (EAEP) extracts using an ultrasonic assisted technique. The antioxidant capacities of the samples were evaluated by free radical scavenging activity (DPPH), cation radical scavenging activity (ABTS), and reducing activity (CUPRAC) and (FRAP). The strongest biological activities were detected in ethanol and methanol extracts. Enzyme inhibition of the propolis samples were determined against the human glutathione S-transferase (GST) and angiotensin converting enzyme (ACE). IC50 values of MEP1, MEP2, and MEP3 samples against the ACE were found as 13.9 µg/mL, 14.8 µg/mL, and 12.8 µg/mL, while against the GST IC50 values of MEP1, MEP2, and MEP3 samples were as 5.92 µg/mL, 9.49 µg/mL, and 5.72 µg/mL. To know the possible causes of the biological test results advanced LC/MS/MS method was applied. trans-ferulic acid, kaempferol, and chrysin were found as the most abundant phenolic compounds in each sample. The propolis extracts obtained using the proper solvent have a good potential to be used in pharmaceuticals to treat the diseases related to oxidative damage, hypertension, and inflammation. Finally, the interactions between chrysin, trans-ferulic acid and kaempferol molecules with ACE and GST receptors were analyzed using molecular docking study. Selected molecules interact with active residues by binding to the active site of the receptors.

Synthesis and acetylcholinesterase enzyme inhibitory effects of some novel 4,5-Dihydro-1H-1,2,4-triazol-5-one derivatives; an in vitro and in silico study.

In this study, a series of novel Schiff bases (4a-4h) containing 1,2,4-triazole structure were synthesized through a condensation reaction of 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones with 3-(4-methylbenzenesulfonyloxy)-benzaldehyde. The structures of 3-alkyl(aryl)-4-[3-(4-methylsulfonyloxy)-benzylidenamino]-4,5-dihydro-1H-1,2,4-triazol-5-ones (4a-h) were determined through a range of spectroscopic techniques (FT-IR, 1H NMR, 13C NMR, and elemental analysis). In addition, enzyme inhibitory properties of the newly synthesized Schiff bases were determined against acetylcholinesterase (AChE). Their Ki values were calculated in the range of 0.70 ± 0.07-8.65 ± 5.6 µM. Besides, their IC50 values were calculated in the range of 0.43-3.87 µM. Finally, in silico molecular docking interactions of the compounds with AChE target enzyme (PDB ID:4EY7) were evaluated using Chimera and AutoDock Vina softwares. The lowest binding energy levels (-12.0 kcal/mol) of the compounds 4e and 4g with AChE target enzyme were verified the best binding affinities and molecular interactions.Communicated by Ramaswamy H. Sarma.

Metal contained Phthalocyanines with 3,4-Dimethoxyphenethoxy substituents: their anticancer, antibacterial activities and their inhibitory effects on some metabolic enzymes with molecular docking studies.

The compounds (3-6) used in this study were re-synthesized in accordance with our previous study. The inhibitory effect of the complexes on some metabolic enzymes was examined and it was demonstrated that the enzymes inhibited by ligands and their complex molecules at micromolar level. The best Ki value for α-glycosidase enzyme was absorved 1.01±0.08 µM for compound 6. The biological activity of ligand and metal complexes against enzymes was compared with molecular docking method. The enzymes used against ligand and metal complexes respectively: Achethylcholinesterase for ID 4M0E (AChE), butyrylcholinesterase for ID 5NN0 (BChE), α-glycosidase for ID 1XSI (α-Gly). ADME analysis was performed to examine the drug properties of the compounds (3-6). Besides, the anticancer properties of the complexes were studied. The doses of all compounds caused significant reductions in MCF-7 cell viability. The 3 and 5 compounds administered to PC-3 cells exhibited a more pronounced cytotoxic effect than the other two compounds (4 and 6). Furthermore, antibacterial activities of these compounds against Escherichia coli and Staphylococcus aureus were examined.Communicated by Ramaswamy H. Sarma.

Some metal chelates with Schiff base ligand: synthesis, structure elucidation, thermal behavior, XRD evaluation, antioxidant activity, enzyme inhibition, and molecular docking studies.

Schiff bases are well-known compounds for having significant biological properties. In this study, a new Schiff base ligand and its metal complexes were synthesized, and their antioxidant and enzyme inhibitory activities were evaluated. The new Schiff base ligand was synthesized with the condensation reaction of 6-tert-butyl 3-ethyl 2-amino-4,5-dihydrothieno[2,3-c]pyridine-3,6(7H)-dicarboxylate and 2-hydroxybenzaldehyde compounds. Fe(II), Co(II), and Ni(II) metal complexes of the novel Schiff base ligand were synthesized and characterized. The purity and molecular formula of the synthesized compounds were identified with elemental analysis, infrared, ultraviolet-visible, mass spectrophotometry, powder XRD, magnetic and thermal measurements. The Schiff base acted as a three dentate chelate. The analytical and spectroscopic data suggested an octahedral geometry for the complexes. The in vitro antioxidant method studies elucidated a more effective antioxidant character of the Schiff base ligand than its metal complexes but a less effective antioxidant potential than the standard antioxidant compounds. The enzyme inhibition potentials of the synthesized compounds for AChE, BChE, and GST enzymes were determined by in vitro enzyme activity methods. The Schiff base ligand was discovered to be the best inhibitor for the AChE and BChE with the values of 7.13 ± 0.84 µM and 5.75 ± 1.03 µM Ki, respectively. Moreover, the Fe(II) complex displayed the best Ki value as 9.37 ± 1.06 µM for the GST enzyme. Finally, molecular docking studies were carried out to see the structural interactions of the compounds. The metal complexes demonstrated better binding affinities with the AChE, BChE, and GST enzymes than the Schiff base ligand. This study identified a potential Schiff base molecule against both AChE and BChE targets to further investigate for in vivo and safety evaluation.

The effects of Daucus carota extract against PC3, PNT1a prostate cells, acetylcholinesterase, glutathione S-transferase, and α-glycosidase; an in vitro-in silico study.

Daucus carota L. ssp. major (DCM) plant is widely used in traditional medicine to treat some types of cancer and various diseases. Therefore, we evaluated the biological activities of this plant to define its effects against prostate cancer (PCa), Alzheimer's disease (AD), oxidation, and diabetes mellitus (DM) as well as identified its phenolic composition. To determine the anti-cancer properties of the plant extract, we treated PCa cells with the extract at a concentration range of 0.25, 0.5, 1, 2, and 4 mg/ml. Significant results were obtained against the PC3 cells compared to normal PNT1a prostate epithelial cells. As a result of precise measurements at the millimolar level, it was observed that the plant extract showed an effective inhibition (IC50 ) against glutathione S-transferase (GST; 12.84 mM), acetyl cholinesterase (AChE; 15.07 mM), and α-Gly (11.75 mM) enzymes when compared with standard inhibitors. Antioxidant activities of DCM methanol extract were determined via two well-known in vitro techniques. The extracts showed antioxidant activities against the DPPH and ABTS+ . The LC-ESI-MS/MS was used to determine the phenolic compounds of methanol extract from DCM. Chlorogenic acid (2,089.096 µg/g), shikimic acid (193.14 µg/g), and coumarin (113.604 µg/g) were characterized as major phenolic compounds. In addition, the interactions of chlorogenic acid, chrysin, coumarin, and shikimic acid with the used three enzymes have been calculated using molecular docking simulation. PRACTICAL APPLICATIONS: Plant natural phenolic compounds have protective effects such as anti-inflammatory, antioxidant, anticarcinogen, and enzyme inhibitory. Therefore, it has an important place in the food and pharmaceutical industry. The present study aims to reveal the enzyme inhibitory, antioxidant, and anticarcinogenic properties of the Daucus carota ssp. Major (DCM) plant extract. Significant results were obtained against the PC3 cells compared to normal PNT1a prostate epithelial cells. DCM extract demonstrated considerable antioxidant activity and inhibitory potential on used metabolic enzymes. These biological effects are thought to have a relationship with rich chemical composition.

Synthesis, Spectroscopic Analysis, and in Vitro/in Silico Biological Studies of Novel Piperidine Derivatives Heterocyclic Schiff-Mannich Base Compounds.

In the present study, 3-substitued-4-(4-hydroxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (S1-8) were synthesized by treating 4-hydroxybenzaldehyde (B) with eight different 3-substitued-4-amino-4,5-dihydro-1H-1,2,4-triazole-5-ones (T1-8) in acetic acid medium, separately. The synthesized Schiff bases (S) were reacted with formaldehyde and secondary amine such as 4-piperidinecarboxyamide to afford novel heterocyclic bases. 3-Substitued-4-(4-hydroxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (T) were treated with 4-piperidinecarboxyamide in the presence of formaldehyde to synthesize eight new 1-(4-piperidinecarboxyamide-1-yl-methyl)-3-substitued-4-(4-hydroxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (M1-8). The structure characterization of compounds was carried out using 1 H-NMR, IR, HR-MS, and 13 C-NMR spectroscopic methods. The inhibitory properties of the newly synthesized compounds were calculated against the acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and glutathione S-transferase (GST) enzymes. Ki values were calculated in the range of 20.06±3.11-36.86±6.17 µM for GST, 17.87±2.91-30.53±4.25 µM for AChE, 9.08±0.69-20.02±2.88 µM for BChE, respectively, Besides, IC50 values were also calculated. Best binding scores of -inhibitors against used enzymes were calculated as -12.095 kcal/mol, -12.775 kcal/mol, and -9.336 kcal/mol, respectively. While 5-oxo-triazole piperidine-4-carboxamide moieties have a critical role in the inhibition of AChE and GST enzymes, hydroxy benzyl moiety is important for BChE enzyme inhibition.

Enzyme inhibitory function and phytochemical profile of Inula discoidea using in vitro and in silico methods.

Many plant species have a large diversity of secondary metabolites with different biological activities. This study aims to assess the phenolic constituent, enzyme inhibitory and antioxidant activities of the aqueous (water) and methanol extracts of Inula discoidea. The enzyme assays showed effective enzyme inhibition of the methanol extract against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), glutathione S-transferase (GST), and α-glycosidase (α-Gly) enzymes. The IC50 values for AChE, BChE, GST, and α-Gly were found as 38.5 mg/mL, 34.65 mg/mL, 77.0 mg/mL, and 40.76 mg/mL, respectively. Antioxidant properties of the aqueous and methanol extracts of I. discoidea were determined by four well-known in vitro techniques (ABTS, CUPRAC, DPPH, and FRAP methods). The antioxidant values of both water and methanol extracts were found to be better than the standard antioxidants (BHA, BHT, ascorbic acid, and α-tocopherol) in ABTS and CUPRAC methods. According to an updated LC-MS/MS technique analysis, quinic acid (21.08 mg/g), protocatechuic acid (4.49 mg/g), and gallic acid (0.48 mg/g) were found as major phenolic compounds of the plant extract. The binding interactions of major phenolic compounds of I. discoidea with the AChE, BChE, GST, and α-Gly enzymes were investigated by the molecular docking studies.

Transition metal complexes of a multidentate Schiff base ligand containing pyridine: synthesis, characterization, enzyme inhibitions, antioxidant properties, and molecular docking studies.

A series of Fe(II), Ni(II), and Pd(II) complexes were prepared with a novel Schiff base ligand containing pyridine moiety. The prepared compounds were characterized using FT-IR, 1H and 13 C NMR, UV-Vis, powder XRD, thermogravimetric analysis, mass spectra, magnetic susceptibility, and elemental analysis. The coordination geometry of Fe(II) and Ni(II) complexes were octahedral, where Fe(II) and Ni(II) metal ions were coordinated by an oxygen atom of the carbonyl group, a nitrogen atom of the azomethine moiety, and a phenolic oxygen atom. The Pd(II) complex had square planar geometry. All of the synthesized compounds were tested for their biochemical properties, including enzyme inhibition and antioxidant activities. According to the in vitro DPPH and FRAP antioxidant methods, the Schiff base ligand and its Fe(II)/Pd(II) complexes showed close antioxidant activities against the standards (BHA, BHT, ascorbic acid, and α-tocopherol). Enzyme inhibitions of the metal complexes were investigated against glutathione S-transferase (GST), acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzymes. The best inhibition value (Ki) was observed for the Ni(II) complex against GST (2.63 ± 0.04 µM). Also, the Pd(II) complex showed the best inhibition value (10.17 ± 1.88 µM) against AChE. Molecular docking specified significant interactions at the active pockets of respective target enzymes. The Ni(II) complex exhibited good binding affinity against both BChE (- 9.0 kcal/mol and 9.36 ± 2.03 µM) and GST (- 7.0 kcal/mol and 2.63 ± 0.04 µM) enzymes.

Synthesis of novel 1,2,3 triazole derivatives and assessment of their potential cholinesterases, glutathione S-transferase enzymes inhibitory properties: An in vitro and in silico study.

In this study, new 1,2,3-triazole derivatives containing chalcone core (1-7) were synthesized. Obtained compounds were characterized by IR, 1H NMR, 13C NMR, and mass studies. Characterized compounds (1-7) inhibitory effects were tested against the glutathione S-transferase (GST), acetylcholinesterase (AChE), and Butyrylcholinesterase (BChE). Their Ki values were in the range of 5.88-11.13 µM on AChE, 5.08-15.12 µM on BChE, and 9.82-13.22 µM on GST. Remarkable inhibitory effects were obtained against three tested metabolic enzymes. Also, binding scores of the best-inhibitors against AChE, BChE, and GST enzymes were detected as -9.969 kcal/mol, -10.672 kcal/mol, and -8.832 kcal/mol, respectively. Isoindoline-1,3-dione and benzothiophene moieties played a critical role in the inhibition of AChE and BChE enzymes, respectively. Phenylene and triazole moieties had the most important interactions for inhibition of the GST enzyme. Therefore, in vivo and in silico results indicated that these compounds can be considered in drug design processes for the treatment of some diseases including Alzheimer's disease (AD), leukemia, and some type of cancer.

Synthesis, design, and assessment of novel morpholine-derived Mannich bases as multifunctional agents for the potential enzyme inhibitory properties including docking study.

The synthesized Schiff Bases were reacted with formaldehyde and secondary amine such as 2,6-dimethylmorpholine to afford N-Mannich bases through the Mannich reaction. 3-Substitued-4-(4-hydroxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (4) were treated with 2,6-dimethylmorpholine in the presence of formaldehyde to synthesize eight new 1-(2,6-dimethylmorpholino-4-yl-methyl)-3-substitued-4-(4-hydroxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (4a-h). The structures of the synthesized eight new compounds were characterized using IR, 1H NMR, 13C NMR, and HR-MS spectroscopic methods. Synthesized compounds inhibitory activity determined against the acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and glutathione S-transferase (GST) enzymes with Ki values in the range 25.23-42.19 µM for AChE, 19.37-34.22 µM for BChE, and 21.84-41.14 µM for GST, respectively. Binding scores of most active inhibitors against AChE, BChE, and GST enzymes were detected as -10.294 kcal/mol, -9.562 kcal/mol, and -7.112 kcal/mol, respectively. The hydroxybenzylidene moiety of the most active inhibitors caused to inhibition of the enzymes through hydrophobic interaction and hydrogen bond.

Determination of anticancer properties and inhibitory effects of some metabolic enzymes including acetylcholinesterase, butyrylcholinesterase, alpha-glycosidase of some compounds with molecular docking study.

Inhibitory effect of the complexes on some metabolic enzyme demonstrated that the enzymes inhibited by ligand and it's complex molecules at the micromolar level. The best inhibition effect for α-glycosidase (α-Gly) enzyme against cobalt complex with Ki value of 3.77 ± 0.58 µM. For achethylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes against SM-Co complex, Ki values of 74.23 ± 5.02 µM and 101.21 ± 12.84 µM Ki were observed, respectively. Molecular docking studies were performed to compare the biological activities of ligands and ligand complexes against enzymes whose names are AChE for ID 4M0E, BChE for ID 5NN0, α-Gly for ID 1XSI respectively. Also, anticancer properties of the complexes studied. The doses of all compounds caused significant reductions in MCF-7 cell viability. Zr compound showed the best cytotoxic activity against the MCF-7 cell. SM ligand administered to PC-3 cells exhibited a more pronounced cytotoxic effect than the SM-Co and Zr compounds.Communicated by Ramaswamy H. Sarma.

Chemical constituent and radical scavenging antioxidant activity of Anthemis kotschyana Boiss.

Phenolic content and antioxidant activity of Anthemis kotschyana Boiss. var. discoidea (A. kotschyana) were reported in this study. The ethanol extract of Anthemis kotschyana (EEA) and the water extract of Anthemis kotschyana (WEA) were prepared and used for biochemical analyses. Radical scavenging antioxidant capacities of EEA and WEA were evaluated by DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging method. Another goal of the study was to evaluate the phenolic compositions of A. kotschyana by liquid chromatography and tandem mass spectrometry (LC-MS/MS). Rhamnetin (5.484 ± 0.020 ppm; µg/g extract) and quinic acid (2.251 ± 0.012 ppm; µg/g extract) were identified as major two compounds in the plant sample. This study will be a scientific base for further studies about A. kotschyana for plant biochemistry and plant-based pharmacological industry.

Synthesis, characterization, powder X-ray diffraction analysis, thermal stability, antioxidant properties and enzyme inhibitions of M(II)-Schiff base ligand complexes.

The Schiff base ligand ((E)-6-methyl-2-(2,3,4-trimethoxybenzylideneamino)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile) and its cobalt(II) and palladium(II) complexes were successfully prepared. The structure of the compounds was elucidated by various techniques (NMR, FT-IR, powder X-ray diffraction, microanalysis, TGA, magnetic susceptibility, mass spectrometry). The Pd(II) complex showed a square planar geometry and the Co(II) complex had an octahedral geometry. ABTS (2,2-azino-bis 3-ethylbenzothiazloine-6-sulphonic acid), DPPH (1,1-diphenyl-2-picrylhydrazyl), FRAP (ferric-reducing antioxidant power) and CUPRAC (cupric reducing antioxidant capacity) in vitro methods were applied to identify the antioxidant features of the synthesized compounds. In addition, glutathione S-transferase and acetyl/butyryl cholinesterase enzymes were examined for possible inhibition capacities of the complexes. According to the enzyme activity measurements, Ru(II) complex inhibited both GST and BChE enzymes, while Fe(II) complex inhibited only AChE enzyme. Furthermore, the antioxidant activities and enzyme inhibitions of the previously synthesized Fe(II) and Ru(II) complexes of the same ligand were examined to make a comparison of the metal complexes.Communicated by Ramaswamy H. Sarma.

ICP-MS and HPLC analyses, enzyme inhibition and antioxidant potential of Achillea schischkinii Sosn.

Achillea schischkinii Sosn. is an endemic plant species and it belongs to Asteraceae family. It is distributed widely in the Central and East Anatolia. This study was carried out for evaluation of the antioxidant activity, enzyme inhibition effect, elemental and phenolic content of A. schischkinii. Briefly, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-glycosidase (α-Gly), and glutathione S-transferase (GST) enzymes were strongly inhibited by A. schischkinii. IC50 values for AChE, BChE, α-Gly, and GST enzymes were found as 19.3 mg/mL, 15.4 mg/mL, 69.3 mg/mL, and 34.7 mg/mL respectively. The antioxidant activity of the sample was evaluated by four different in vitro bioanalytical methods. Besides, the concentrations of twelve elements in A. schischkinii were analyzed by ICP-MS technique. Zn (50.6 ppm), Mn (23.0 ppm), and Cu (12.7 ppm) were found as major elements. Furthermore, catechin (20.8 µg/mg extract), trans-ferulic acid (18.3 µg/mg extract), and gallic acid (11.2 µg/mg extract) were characterized as major phenolic compounds by using HPLC. PRACTICAL APPLICATIONS: Acetylcholinesterase, butyrylcholinesterase, α-glycosidase, and glutathione s-transferase enzymes have crucial functions on metabolism. Enzyme inhibition or activation mostly attributed to some health disorders such as Alzheimer's disease, Diabetes mellitus, cancer and hyperglycemia. Phenolic contents are responsible for effective biological activity. This study evaluated the phenolic content and antioxidant activity of Achillea schischkinii as well as the inhibition effect against four metabolic enzymes. The results would be beneficial for using the plant in the food industry and pharmacological process.

Phytochemical Content, Antidiabetic, Anticholinergic, and Antioxidant Activities of Endemic Lecokia cretica Extracts.

The aim of this work was to investigate the enzyme inhibition, antioxidant activity, and phenolic compounds of Lecokia cretica (Lam.) DC. Acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glycosidase enzymes were strongly inhibited by the L. cretica extracts. IC50 values for the three enzymes were found as 3.21 mg/mL, 2.1 mg/mL, and 2.07 mg/mL, respectively. Antioxidant activities were examined in both aqueous and ethanol (EtOH) extracts using CUPRAC, FRAP, and DPPH method. Also, the phenolic compounds of the endemic plant were identified and quantified by using HPLC/MS/MS. According to the results, the extracts have remarkable antioxidant activities. The most abundant phenolic acids of L. cretica in EtOH extract were determined as quinic acid (12.76 mg/kg of crude extract), chlorogenic acid (3.39 mg/kg), and malic acid (2.38 mg/kg).

Phytochemical content, antioxidant activity, and enzyme inhibition effect of Salvia eriophora Boiss. & Kotschy against acetylcholinesterase, α-amylase, butyrylcholinesterase, and α-glycosidase enzymes.

Many taxa of Salvia genus have been used in herbal beverages, food flavoring, cosmetics, and pharmaceutical industry. In this paper, chemical compounds of Salvia eriophora (S. eriophora) leaves were determined by LC-MS/MS (Liquid Chromatography tandem Mass Spectrometry). Salvigenin (158.64 ± 10.8 mg/kg), fumaric acid (123.09 ± 8.54 mg/kg), and quercetagetin-3.6-dimethylether (37.85 ± 7.09 mg/kg) were detected as major compounds in the ethanol extract, whereas fumaric acid (555.96 ± 38.56 mg/kg), caffeic acid (103.62 ± 20.51 mg/kg), and epicatechin (83.19 ± 8.43 mg/kg) were detected as major compounds in the water extract. Furthermore, enzyme inhibition of S. eriophora against acetylcholinesterase (AChE), α-amylase (AM), butyrylcholinesterase (BChE), and α-glycosidase (AG) enzymes were detected. AChE, BChE, AG, and AM enzymes were very strongly inhibited by S. eriophora water extract (WES) and S. eriophora methanol extract (MES). Additionally, antioxidant potential of S. eriophora was determined by in vitro analytical methods. IC50 values of WES and MES were performed for radicals. PRACTICAL APPLICATIONS: Metabolic enzymes have crucial functions on living systems due to inhibition or activation of them mainly attributed with some health disorders. AChE, BChE, AM, and AG enzymes have important roles on carbohydrate metabolism or cholinergic pathways. The relation between enzyme inhibition effect and phenolic compounds or antioxidant activity need to be confirmed. Thus, many studies tested to clarify this relation for pure samples or plant extracts. To the best of our knowledge, this is the first report about inhibition effects of Salvia eriophora extracts against AChE, BChE, AM, and AG enzymes as well as their phenolic contents and antioxidant activities.

Spectroscopic and Structural Characterization, Enzyme Inhibitions, and Antioxidant Effects of New Ru(II) and Ni(II) Complexes of Schiff Base.

The new complex compounds [RuLCl(p-cymene)] ⋅ 3H2 O and [NiL2 (H2 O)2 ] ⋅ 3H2 O (L: 1-{4-[(2-hydroxy-3-methoxybenzylidene)amino]phenyl}ethanone) were prepared and characterized using FT-IR, 1 H- and 13 C-NMR, mass spectroscopy, TGA, elemental analysis, X-ray powder diffraction and magnetic moment techniques. Octahedral geometry for new Ni(II) and Ru(II) complexes was proposed. Thermal decomposition confirmed the existence of lattice and coordinated water molecule in the complexes. To determine the antioxidant properties of Schiff base ligand and its Ni(II), Ru(II) metal complexes, FRAP, CUPRAC, ABTS and DPPH methods of antioxidant assays were used. Moreover, enzyme inhibition of complexes was evaluated against carbonic anhydrase I and II isoenzymes (CA I and CA II) and acetylcholinesterase (AChE). For CA I and CA II, the best inhibition enzymes, was the Ni(II) complex with 62.98±18.41, 86.17±23.62 Ki values, whereas this inhibition effect showed ligand with 24.53±2.66 Ki value for the AChE enzyme.

Evaluation of antioxidant capacity of endemic plant Marrubium astracanicum subsp. macrodon: Identification of its phenolic contents by using HPLC-MS/MS.

Antioxidant properties of Marrubium astracanicum subsp. macrodon solvent extracts were measured by both cupric ion reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP) methods. According to the results, ethanol extract of the plant has high potential of reducing antioxidant activity on CUPRAC method. However, water extract of the plant has lower antioxidant potential. Furthermore, both water and ethanol extracts showed lower reducing antioxidant activity compare to standards on FRAP method. Moreover, the composition and content of plant leaves were detected by UHPLC-ESI-MS/MS. High concentrations of quinic acid, p-coumaric acid and malic acid were determined.

Assessment of Antimicrobial and Antioxidant Activities of Nepeta trachonitica: Analysis of Its Phenolic Compounds Using HPLC-MS/MS.

Continuing our work on the sources of natural bioactive compounds, we evaluated the antimicrobial and antioxidant activities of Nepeta trachonitica as well as its major phenolic content using the high-performance liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS) technique. For antioxidant activity, ferric reducing antioxidant power (FRAP) and cupric ion reducing antioxidant capacity (CUPRAC) methods were performed to measure the reducing power and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was employed to evaluate the radical scavenging activity of the sample. For antimicrobial activity, three Gram-positive and four Gram-negative microbial species as well as three fungi species were tested. N. trachonitica appeared to have reasonable antioxidant activity and decent antimicrobial activity as indicated by the inhibition of the organisms' growth. The most susceptible species were Bacillus subtilis ATCC 6633 and Escherichia coli ATCC 11229 among the organisms tested. Ethanol extract of the plant has the highest effect on Saccharomyces cerevisiae but no effect on Yarrowia lipolytica. The HPLC-MS/MS analysis showed that at least 11 major phenolic compounds of N. trachonitica exist, the major ones being rosmarinic acid, chlorogenic acid and quinic acid. The obtained results suggest that N. trachonitica could be a promising source for food and nutraceutical industries because of its antimicrobial and antioxidant properties and phenolic compounds.