Crude extract of ChE from the liver of Puntius javanicus was purified using procainamide-sepharyl 6B. S-Butyrylthiocholine iodide (BTC) was selected as the specific synthetic substrate for this assay with the highest maximal velocity and lowest biomolecular constant at 53.49 µmole/min/mg and 0.23 mM, respectively, with catalytic efficiency ratio of 0.23. The optimum parameter was obtained at pH 7.5 and optimal temperature in the range of 25 to 30°C. The effect of different storage condition was assessed where ChE activity was significantly decreased after 9 days of storage at room temperature. However, ChE activity showed no significant difference when stored at 4.0, 0, and -25°C for 15 days. Screening of heavy metals shows that chromium, copper, and mercury strongly inhibited P. javanicus ChE by lowering the activity below 50%, while several pairwise combination of metal ions exhibited synergistic inhibiting effects on the enzyme which is greater than single exposure especially chromium, copper, and mercury. The results showed that P. javanicus ChE has the potential to be used as a biosensor for the detection of metal ions.
A phytochemical investigation on the ethyl acetate soluble fraction of Lonicera quinquelocularis (whole plant) led to the first time isolation of one new phthalate; bis(7-acetoxy-2-ethyl-5-methylheptyl) phthalate (3) and two new benzoates; neopentyl-4-ethoxy-3, 5-bis (3-methyl-2-butenyl benzoate (4) and neopentyl-4-hydroxy-3, 5-bis (3-methyl-2-butenyl benzoate (5) along with two known compounds bis (2-ethylhexyl phthalate (1) and dioctyl phthalate (2). Their structures were established on the basis of spectroscopic analysis and by comparison with available data in the literature. All the compounds (1-5) were tested for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities in dose dependent manner. The IC50 (50% inhibitory effect) values of compounds 3 and 5 against AChE were 1.65 and 3.43 µM while the values obtained against BChE were 5.98 and 9.84 µM respectively. Compounds 2 and 4 showed weak inhibition profile.
Two series of novel acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors containing benzimidazole core structure were synthesized by a four-step reaction pathway starting from 4-fluoro-3-nitrobenzoic acid as the basic compound. The structure of the novel benzimidazoles was characterized and confirmed by the elemental and mass spectral analyses as well as (1)H NMR spectroscopic data. Of the 34 novel synthesized compounds, three benzimidazoles revealed AChE inhibition with IC50<10 μM. The highest inhibitory activity (IC50=5.12 μM for AChE and IC50=8.63 μM for BChE) corresponds to the compound 5IIc (ethyl 1-(3-(1H-imidazol-1-yl)propyl)-2-(4-nitrophenyl)-1H-benzo[d]imidazole-5-carboxylate). The relationship between lipophilicity and the chemical structures as well as their limited structure-activity relationship was discussed.
Series of hitherto unreported piperidone grafted pyridopyrimidines synthesized through ionic liquid mediated multi-component reaction. These compounds were evaluated for their inhibitory activities against AChE and BChE enzymes. All the compounds displayed considerable potency against AChE with IC50 values ranging from 0.92 to 9.11 μM, therein compounds 6a, 6h and 6i displayed superior enzyme inhibitory activities compared to standard drug with IC50 values of 0.92, 1.29 and 2.07 μM. Remarkably, all the compounds displayed higher BChE inhibitory activity compared to galantamine with IC50 values of 1.89-8.13 μM. Molecular modeling, performed for the most active compounds using three dimensional crystal structures of TcAChE and hBChE, disclosed binding template of these inhibitors into the active site of their respective enzymes.
The release of pollutants, especially heavy metals, into the aquatic environment is known to have detrimental effects on such an environment and on living organisms including humans when those pollutants are allowed to enter the food chain. The aim of this study is to analyse the damage to Clarias gariepinus' liver caused by exposure to different concentrations of copper. In the present study, samples of C. gariepinus were exposed to sub-lethal copper sulphate (CuSO4) concentrations (from 0.2 to 20.0 mg/L) for 96 h. Physiological and behavioural alterations were observed with respect to their swimming pattern, mucus secretion and skin colour. Mortality was also observed at high concentrations of copper. Histopathological alterations of the liver were analysed under light, transmission and scanning electron microscopies. The liver of the untreated group showed normal tissue structures, while histopathological abnormalities were observed in the treated fish under light and electron microscopes with increased copper concentrations. Histopathological abnormalities include necrosis, melanomacrophage, hepatic fibrosis and congested blood vessels. In addition, the enzyme activity of liver cholinesterase (ChE) was also found to be affected by copper sulphate, as 100% of cholinesterase activity was inhibited at 20.0 mg/L. Thus, liver enzyme activity and histopathological changes are proven to be alternative sources for biomarkers of metal toxicity.
Novel thiazolopyrimidine derivatives have been synthesized via microwave assisted, domino cascade methodology in ionic liquid and evaluated in vitro for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities. Among the newly synthesized compounds 6d, 6a, 6e and 6b displayed higher AChE inhibitory activity than standard drug, galanthamine, with IC50 values of 0.53, 1.47, 1.62 and 2.05μM, respectively. Interestingly, all the compounds except for 6m-r and 6x displayed higher BChE inhibitory potentials than galanthamine with IC50 values ranging from 1.09 to 18.56μM. Molecular docking simulations for 6d possessing the most potent AChE and BChE inhibitory activities, disclosed its binding interactions at the active site gorge of AChE and BChE enzymes.
Paddy (unmilled rice), milled rice and maize-bound 14C residues were prepared using 14C-succinate-labelled malathion at 10 and 152 ppm. After 3 months, the bound residues accounted for 12%, 6.5% and 17.7% of the applied dose in paddy, milled rice and maize respectively in the grains treated at 10 ppm. The corresponding values for the 152 ppm were 16.6%, 8.5% and 18.8%. Rats fed milled rice - bound 14C-residues eliminated 61% of the 14C in the faeces and 28% in the urine. The corresponding percentages for paddy and maize were 72%, 9% and 53%, 41% respectively; indicating that bound residues from milled rice and maize were moderately bioavailable. When rice-bound malathion residues (0.65 ppm in feed) were administered to rats in a 5 week feeding study, no signs of toxicity were observed. Plasma and RBC cholinesterase activities were slightly inhibited: blood urea nitrogen was significantly elevated in the test animals. Other parameters examined showed no or marginal changes.
Novel mono and bis spiropyrrolidine derivatives were synthesized via an efficient ionic liquid mediated, 1,3-dipolar cycloaddition methodology and evaluated in vitro for their AChE and BChE inhibitory activities in search for potent cholinesterase enzyme inhibitors. Most of the synthesized compounds displayed remarkable AChE inhibitory activities with IC50 values ranging from 1.68 to 21.85 μM, wherein compounds 8d and 8j were found to be most active inhibitors against AChE and BChE with IC50 values of 1.68 and 2.75 μM, respectively. Molecular modeling simulation on Torpedo californica AChE and human BChE receptors, showed good correlation between IC50 values and binding interaction template of the most active inhibitors docked into the active site of their relevant enzymes.
Extensive chromatographic separations performed on the basic (pH=8-10) chloroform soluble fraction of Aconitum heterophyllum resulted in the isolation of three new diterpenoid alkaloids, 6β-Methoxy, 9β-dihydroxylheteratisine (1), 1α,11,13β-trihydroxylhetisine (2), 6,15β-dihydroxylhetisine (3), and the known compounds iso-atisine (4), heteratisine (5), hetisinone (6), 19-epi-isoatisine (7), and atidine (8). Structures of the isolated compounds were established by means of mass and NMR spectroscopy as well as single crystal X-ray crystallography. Compounds 1-8 were screened for their antioxidant and enzyme inhibition activities followed by in silico studies to find out the possible inhibitory mechanism of the tested compounds. This work is the first report demonstrating significant antioxidant and anticholinesterase potentials of diterpenoid alkaloids isolated from a natural source.
A series of novel hybrid spiro heterocycles comprising pyrrolizine, spiroxindole and piperidine moieties was synthesized chemo-, regio- and stereoselectively in good yields from 1,3-dipolar cycloaddition reaction of a series of 1-acryloyl-3,5-bisarylmethylidenepiperidin-4-ones with azomethine ylides generated in situ from 5-choloroisatin and l-proline in methanol. These cycloadducts displayed significant cholinesterase inhibitory activity. Among the compounds screened, 8g and 8e, showed maximum inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinestrase (BChE) with IC50 values of 3.33 and 3.13μM, respectively.
Coriandrum sativum L., commonly known as coriander and belonging to the family Apiaceae (Umbelliferae), is cultivated throughout the world for its nutritional value. The present study was undertaken to investigate the effects of fresh Coriandrum sativum leaves (CSL) on cognitive functions, total serum cholesterol levels and brain cholinesterase activity in mice. In this study, CSL (5, 10 and 15% w/w of diet) was fed orally with a specially prepared diet for 45 days consecutively to experimental animals. Elevated plus-maze and passive avoidance apparatus served as the exteroceptive behavioral models for testing memory. Diazepam, scopolamine and ageing-induced amnesia served as the interoceptive behavioral models.
Extensive research on prenatal alcohol exposure has proven the potent teratogenicity of this substance of abuse. Children born to alcoholic mothers are often diagnosed with fetal alcohol syndrome (FAS). Those afflicted with FAS often have muscle weakness, muscle wasting, and atrophy. This study assessed the effects of prenatal alcohol exposure on the developing rat neuromuscular system.
The genus Silene is renowned in Turkey for its traditional use as food and medicine. Currently, there are 138 species of Silene in Turkey, amongst which have been several studies for possible pharmacological potential and application in food industry. However, there is currently a paucity of data on Silene salsuginea Hub.-Mor. This study endeavours to access its antioxidant, enzyme inhibitory, and anti-inflammatory properties. Besides, reversed-phase high-performance liquid chromatography-diode array detector (RP-HPLC-DAD) was used to detect phenolic compounds, and molecular docking was performed to provide new insights for tested enzymes and phenolics. High amounts of apigenin (534 μg/g extract), ferulic acid (452 μg/g extract), p-coumaric acid (408 μg/g extract), and quercetin (336 μg/g extract) were detected in the methanol extract while rutin (506 μg/g extract) was most abundant in the aqueous extract. As for their biological properties, the methanol extract exhibited the best antioxidant effect in the DPPH and CUPRAC assays, and also the highest inhibition against tyrosinase. The aqueous extract was the least active enzyme inhibitor but showed the highest antioxidant efficacy in the ABTS, FRAP, and metal chelating assays. At a concentration of 15.6 μg/mL, the methanol extract resulted in a moderate decrease (25.1%) of NO production in lipopolysaccharide-stimulated cells. Among the phenolic compounds, epicatechin, (+)-catechin, and kaempferol showed the highest binding affinity towards the studied enzymes in silico. It can be concluded that extracts of S. salsuginea are a potential source of functional food ingredients but need further analytical experiments to explore its complexity of chemical compounds and pharmacological properties as well as using in vivo toxicity models to establish its maximum tolerated dose.