Anti-acetylcholinesterase Activity Research Articles

Exploring the impact of novel thiazole-pyrazole fused benzo-coumarin derivatives on human serum albumin: Synthesis, photophysical properties, anti-cholinergic activity, and interaction studies

Derivatives of thiazole-pyrazole fused benzo-coumarin compounds were successfully synthesized and characterized, followed by a comprehensive spectroscopic investigation on various photophysical properties in different media. The multipronged approach using steady state and time resolved fluorescence spectroscopy pointed out the impact of substitution in the estimated spectroscopic and other physicochemical properties of the systems. Further, the evaluation of anti-acetylcholinesterase (anti-AChE) activity yielded significant insight into the therapeutic potential of the synthesized coumarinyl compounds for the treatment of Alzheimer's disease (AD). The findings revealed a non-competitive mode of inhibition mechanism, with an estimated IC50 value of 67.72 ± 2.00 nM observed for one of the investigated systems as AChE inhibitor. Notably, this value is even lower than that of an FDA-approved AD drug Donepezil (DON), indicating the enhanced potency of the coumarin derivatives in inhibiting AChE. Interestingly, significant diminution in inhibition was observed in presence of human serum albumin (HSA) as evidenced by the relative increase in IC50 value by 8 ∼ 39 % in different cases, which emphasized the role of albumin proteins to control therapeutic efficacies of potential medications. In-depth spectroscopic and in-silico analysis quantified the nature of interactions of the investigated systems with HSA and AChE. Overall, the outcomes of this study provide significant understanding into the biophysical characteristics of novel thiazole-pyrazole fused benzo-coumarin systems, which could aid in the development of new cholinergic agents for the treatment of AD and materials based on coumarin motifs.

Chemical profiling and biological assessment of trunk bark essential oil from Eucalyptus camaldulensis: In vitro study coupled with chemoinformatics calculations

The aim of this study was to identify the chemical composition of the essential oil of Eucalyptus camaldulensis trunk bark (ECEO) and to investigate its in vitro antioxidant, anti-5-lipoxygenase, anti-acetylcholinesterase, anti-butyrylcholinesterase and anti-α-amylase activities. The chemical composition of the essential oil extracted from trunk bark of E. camaldulensis was analyzed by GC-FID and GC/MS, twenty-one compounds were identified accounting for 96.3% of total oil. The phytochemical profile of this essential oil was distinguished by the dominance of oxygenated monoterpenes (58.4%) with Δ8,9-dehydro-4-hydroxythymoldimethyl ether (31.4%), thymohydroquinone methyl ether (21.9%), and modephen-8-β-ol (12.9%) as major compounds. Additionally, the ECEO was examined for its antioxidant activity using three in vitro tests (DPPH, ABTS•+ radicals and H2O2 assays). ECEO showed the highest effect in the hydrogen peroxide assay (IC50= 33.55 ± 2.10 µg/mL). Additionally, ECEO exhibited significant anti-α-amylase and anti-acetylcholinesterase activities (IC50= 10.02 ± 1.88 and 5.88 ± 0.81 μg/mL, respectively). In silico analysis was in agreement with the in vitro studies in which most potent components of ECEO showed strong interactions into the binding sites of the enzymes (PDBs: 4EY6 (acetylcholinesterase), and 7TAA (α-amylase)) and good ADMET properties. Our results might be due to the synergistic effect of constituents present in this essential oil or acting separately. The obtained results pave the way for the promising applications the essential oil obtained from E. camaldulensis trunk bark in food and the pharmaceutical fields.

2a-Alkylnorlitebamines and (7a,8)-didehydroisohomoaporphines: Synthesis and antiacetylcholinesterase activity verified via in silico molecular docking

As N-alkyl-norlitebamines have been demonstrated to possess antiacetylcholinesterase activity, this study aimed to prepare related analogs to verify their structure–activity relationship. The compounds with the chemical skeletons of 2a-alkylnorlitebamines (6b–6e) and (7a,8)-didehydroisohomoaporphines (8b–8e, 9a, and 10b–10e) were designed and synthesized. In silico molecular docking of the 13 compounds on the acetylcholinesterase template indicated that 8a and 10b showed the highest docking scores (ΔG) (−20.56 Kcal/mol and −19.76 Kcal/mol, respectively). The reaction of peracylsecolaurolitsines under the modified Bischler–Napieralski procedure and subsequent NaBH4 reduction yielded 7a-alkyl- B homoaurolitsines 8a−8e, possessing a new skeleton, besides the expected 2a-alkyl-norlitebamines 10b−10e. Among these compounds, the two with the highest docking scores [Δ7a (8)- B homoaurolitsine (8a) and 2a-methyl-norlitebamine (10b)] showed better inhibitory activities against acetylcholinesterase (eel) with IC50 value of 24.71 μM and 26.13 μM, respectively. Therefore, compounds 8a and 10b could serve as leads for exploring potential acetylcholinesterase inhibitors for the treatment of Alzheimer’s disease.

Bioassays guided isolation of berberine from Berberis lycium and its neuroprotective role in aluminium chloride induced rat model of Alzheimer's disease combined with insilico molecular docking.

Berberis lycium is an indigenous plant of Pakistan that is known for its medicinal properties. In the current study, we investigated the anti-Alzheimer's effect of berberine isolated from Berberis lycium. Root extract of B. lycium was subjected to acetylcholinesterase inhibition assay and column chromatography for bioassays guided isolation of a compound. The neuroprotective and memory improving effects of isolated compound were evaluated by aluminium chloride induced Alzheimer's disease rat model, elevated plus maze (EPM) and Morris water maze (MWM) tests., Levels of dopamine and serotonin in rats brains were determined using HPLC. Moreover, western blot and docking were performed to determine interaction between berberine and β-secretase. During fractionation, ethyl acetate and methanol (3:7) fraction was collected from solvent mixture of ethyl acetate and methanol. This fraction showed the highest anti-acetylcholinesterase activity and was alkaloid positive. The results of TLC and HPLC analysis indicated the presence of the isolated compound as berberine. Additionally, the confirmation of isolated compound as berberine was carried out using FTIR and NMR analysis. In vivo EPM and MWM tests showed improved memory patterns after berberine treatment in Alzheimer's disease model. The levels of dopamine, serotonin and activity of antioxidant enzymes were significantly (p<0.05) enhanced in brain tissue homogenates of berberine treated group. This was supported by decreased expression of β-secretase in berberine treated rat brain homogenates and good binding affinity of berberine with β-secretase in docking studies. Binding energies for interaction of β-secretase with berberine and drug Rivastigmine is -7.0 kcal/mol and -5.8 kcal/mol respectively representing the strong interactions. The results of docked complex of secretase with berberine and Rivastigmine was carried out using Gromacs which showed significant stability of complex in terms of RMSD and radius of gyration. Overall, the study presents berberine as a potential drug against Alzheimer's disease by providing evidence of its effects in improving memory, neurotransmitter levels and reducing β-secretase expression in the Alzheimer's disease model.

Citharexylum spinosum promotes antioxidant, anti-inflammatory, and anti-acetylcholinesterase activities

Citharexylum spinosum promotes antioxidant, anti-inflammatory, and anti-acetylcholinesterase activities

Assessment of the Chemical Profile and Potential Medical Effects of a Flavonoid-Rich Extract of Eclipta prostrata L. Collected in the Central Highlands of Vietnam.

Eclipta prostrata L. (EPL), a medicinal plant, is widely utilized in the central highlands of Vietnam. This study aims to assess the chemical profile and potential medical effects of an EPL extract rich in flavonoids. A total of 36 secondary metabolites were identified from the EPL extract through GC-MS and UHPLC-UV analysis. Among them, 15 volatile compounds and several phenolic and flavonoid chemicals, including salicylic acid, epicatechin gallate, isovitexin, and apigetrin, were reported in EPL extract for the first time. This herbal extract demonstrated moderate inhibition against α-amylase and α-glucosidase, and high anti-oxidant and anti-acetylcholinesterase activities (IC50 = 76.8 ± 0.8 μg/mL). These promising attributes can be likely attributed to the high levels of major compounds, including wedelolactone (1), chlorogenic acid (3), epicatechin gallate (6), salicylic acid (8), isovitexin (9), apigetrin (11), and myricetin (12). These findings align with the traditional use of EPL for enhancing memory and cognitive function, as well as its potential benefits in diabetes management. The results of the molecular docking study reveal that the major identified compounds (1, 6, 9, and 11) showed a more effective acetylcholinesterase inhibitory effect than berberine chloride, with good binding energy (DS values, -12.3 to -14.3 kcal/mol) and acceptable values of RMSD (1.02-1.67 Å). Additionally, almost all the identified major compounds exhibited good ADMET properties within the required limits.

Cyanidin Ameliorates Bisphenol A-Induced Alzheimer's Disease Pathology by Restoring Wnt/β-Catenin Signaling Cascade: an In Vitro Study.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder causing memory loss and cognitive decline, linked to amyloid-beta (Aβ) plaques and hyperphosphorylated tau protein accumulation in the brain. Environmental pollutant bisphenol A (BPA) has been implicated in AD pathology due to its neurotoxic effects. This study aims to evaluate cyanidin from flower bracts of Musa acuminata Colla (red variety; AAA group) for its neuroprotective properties against BPA-induced AD pathology. The extraction of cyanidin was optimized using 70% ethanol in acidified water, showing promising anti-acetylcholinesterase activity. Cyanidin was effectively purified from the resultant extract and characterized using spectroscopic techniques. Two gradient doses of cyanidin (90 and 10µg/ml) were determined based on cell viability assay. The role of cyanidin in promoting nerve growth and differentiation was assessed in PC12 cells for up to 72h. A discernible and statistically significant difference was assessed in neurite extension at both doses at 72h, followed by pre-treatment with cyanidin. BPA stimulation significantly increased the p-tau expression compared to the control (p < 0.0001). Pre-treatment with cyanidin reduced the tau expression; however, a significant difference was observed compared to control cells (p = 0.0003). Cyanidin significantly enhanced the mRNA expression of Wnt3a (p < 0.0001), β-catenin (p = 0.0004), and NeuroD1 (p = 0.0289), and decreased the expression of WIF1(p = 0.0040) and DKK1 (p < 0.0001), which are Wnt antagonist when compared to cells stimulated with BPA. Conclusively, our finding suggests that cyanidin could agonize nerve growth factor and promote neuronal differentiation, reduce tau-hyperphosphorylation by restoring the Wnt/β-catenin signaling cascade, and thereby render its neuroprotective potential against BPA-induced AD pathology.

In vitro Anti-Oxidation and Anti-Cholinesterase Activities of Tuna and Chicken Hydrolysates and their Maillard Reaction Products

Objective: To evaluate the anti-oxidation and anticholinesterase activities and cell viability of chicken and tuna hydrolysates and their Maillard reaction products.Material and Methods: Maillard reaction products (MRPs) derived from chicken or tuna hydrolysates were prepared by heating the hydrolysate with glucose at 84°C for 90 minutes. Physical characteristics, ultraviolet (UV) absorbance, browning intensity, protein concentrations, molecular weight distribution, and amino acid profiles of the hydrolysates and MRPs were determined. The anti-oxidation properties of the hydrolysate and MRPs were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Anti-cholinesterase activities were evaluated using Ellman’s method. Cell viability of the samples was evaluated in RAW 264.7 cells.Results: The MRPs presented as brown to dark brown liquids with Brix values ranging from 61.33 to 64.17 °Brix. The pH value ranged from 5.31 to 6.20. The UV absorbance at 294 nm and browning intensity at 420 nm of the MRPs were less than the absorbance of the corresponding hydrolysates. The protein concentrations were 41-44% (hydrolysates) and 18-20% (MRPs). The major constituents of the hydrolysates and MRPs were small molecules (MW&lt;300 Da). The samples exhibited anti-oxidative activity (EC50 2.03 - 3.51 mg/mL) and anti-acetylcholinesterase activity (45-52% inhibition at 0.5 mg/mL). Both hydrolysates and MRPs showed no toxicity to RAW 264.7 cells at concentrations up to 1 mg/mL.Conclusion: Chicken and tuna hydrolysates and their MRPs exhibited mild anti-oxidative and moderate acetylcholinesterase inhibitory activities.

Acaricidal, larvacidal, and repellent activity of green synthesized silver nanoparticles against Hyalomma dromedarii.

We aimed at determination of acaricidal, larvacidal, and repellent activities of green synthesized silver nanoparticles (SNP) against Hyalomma dromedarii as one of the most common ticks in camels. SNP were green synthesized by reducing Lupinus albus extract through the precipitation technique. The acaricidal, larvicidal, and repellent activity of SNP against H. dromedarii was studied through the adult immersion test (AIT), the larval packet test (LPT), the vertical movement behavior of tick's larvae method, anti-acetylcholinesterase (AChE) activity, and oxidative enzyme activity. The green synthesized SNP displayed a spherical form with a size ranging from 25-90 nm; whereas the most distribution of particles size was reported at 50-65 nm. SNP dose-dependently (p<0.001) increased the mortality rate of H. dromedarii adult; whereas at 16 and 32 µg/mL completely killed the adult females. Treatment of exposure of H. dromedarii adult to SNP markedly (p<0.001) declined the mean number, weight, and hatchability of eggs. Treatment of H. dromedarii larvae with SNP reduced the viability rate of larvae with the LC50 and LC90 values of 3.1 and 6.9 µg/mL, respectively. Exposure of H. dromedarii larvae to SNP, especially at ½ LC50 and LC50, markedly (p<0.001) increased the oxidative stress and declined the level of antioxidant enzymes in H. dromedarii larvae; whereas, markedly suppressed the AChE activity of the larvae stage of H. dromedarii in comparison to the control group. These results showed that SNP green synthesized by L. albus extract had promising acaricidal, larvicidal and repellent activity against H. dromedarii adults and larvae as a dose-dependent response. SNP also considrably decreased the level of acetylcholinesterase and antioxidant activity and also provokes oxidative stress in H. dromedarii larvae. However, more investigation must be designed to clear the accurate mechanisms and the efficacy of SNP in practical use.

Anti-adenosine deaminase, anti-neuraminidase, anti-xanthine oxidase, anti-acetylcholinesterase and antioxidant activities of parsley extract

IntroductionAlthough drugs are often used in the treatment of metabolic diseases, their bioavailability as well as resistance to diseases and decrease in effects pose serious challenges. For these reasons, the importance of plants in the treatment and prevention of diseases is increasing day by day, and herbal sources have been in use since ancient times. Parsley is an easy-to-produce herb that is used as food around the world. It continues to be used in scientific studies due to its high phenolic and nutritional content. Due to its antihyperglycemic, antihyperlipidemic, anticoagulant, antioxidant, antimicrobial, and laxative activities, it still remains popular among scientific researchers. Adenosine deaminase, xanthine oxidase, neuraminidase, and acetylcholinesterase are biomarkers of many metabolic diseases such as cancer, diabetes, Alzheimer's disease, and influenza. The aim of this study is to investigate the inhibitory activities of aqueous parsley extract on adenosine deaminase, xanthine oxidase, neuraminidase, acetylcholinesterase, as well as its antioxidant activities. MethodsStandard methods were used to determine the inhibitory effect of aqueous parsley extract on adenosine deaminase, xanthine oxidase, neuraminidase, and acetylcholinesterase. Also, total phenolic content, DPPH (1,1′-diphenyl-2-picrylhydrazyl) radical scavenging activity and reducing power of the extract were evaluated. ResultsAqueous parsley extract inhibited adenosine deaminase, xanthine oxidase, neuraminidase and acetylcholinesterase. The phenolic compounds of parsley are potentially responsible for both antioxidant activities and enzyme inhibition activities of the plant. ConclusionThe results showed that parsley extract has inhibitory effects on the enzymes studied and has a very good antioxidant activity.

Phytochemical composition, anti-amylase and anti-acetylcholinesterase activities of leaf extracts and herbal tea of Dolichandrone serrulata (DC.) seem

The number of elderly population is continually growing in Thailand. Major health problems mostly occurred in the elder are non-communicable diseases namely Alzheimer's disease and type 2 diabetes mellitus. In current study, phytochemical composition, anti-amylase and anti-acetylcholinesterase activities of leaf extracts and herbal tea from Dolichandrone serrulata (DC.) Seem were determined. The result showed that extracts and herbal tea samples of D. serrulata leaves had effective in inhibition of amylase (an effective concentration at half maximum (EC50) = 1.21 to 23.80 mg/ml) and acetylcholinesterase activities (EC50 = 2.63 to 49.55 mg/ml). The effect of infusion time on the inhibition of amylase indicated that the best infusion time for preparing herbal tea beverage was 3 min, while the inhibition of acetylcholinesterase was 5 min. The fourier transform infrared spectroscopy (FTIR) and gas chromatograph - mass spectrometer (GC–MS) data indicated the presence of phytochemicals in the extracts and herbal tea samples related to phenolic compounds and flavonoids. The principal component analysis (PCA) result from FTIR data could discriminate herbal tea samples from the ethanol and aqueous extracts better than the PCA biplot of anti-amylase activity and anti-acetylcholinesterase activity.

Chemical components and anti-acetylcholinesterase activity of Piper lolot leaves oil

Essential oil of Piper lolot leaves in Quang Nam-Da Nang do obtain via the steam distillation method with oil collection efficiency reaching 0.68%. The chemical components of the essential oil from Piper lolot leaves in Quang Nam-Da Nang are determined via the GC-MS method that includes 20 compositions (99.97%), among which the main compositions are myristicin (72.70%), asarone (5.16%), β-bisabolene (3.59%), γ-asarone (3.52%), caryophyllene (2.63%), and α-copaene (1.93%). The essential oil of Piper lolot leaves in Quang Nam-Da Nang also showed potent anti-acetylcholinesterase activity with IC50 (µg/mL) = 28.72±2.80 compared to galantamine (a positive control) and essential oils, extract from Piper species

A comparative study on chemical profiles and biological activities of different extracts of three Verbascum species from Turkey: In vitro, in silico and network pharmacological approaches

The present study aimed to evaluate the antioxidant and enzyme inhibition properties of aerial part of Verbascum cheiranthifolium Boiss. V. myriocarpum Boiss. & Heldr. and V. pyroliforme (Boiss. & Heldr.) Kuntze as well as their chemical profiles. Results showed that MeOH and hydromethanol recovered the highest total polyphenolic content with highest content obtained from V. cheiranthifolium (27.61and 27.69 mg GAE/g respectively) and V. myriocarpum (24.24 and 25.34 GAE/g respectively). The estimated content of verbascoside was quite higher in V. cheiranthifolium (987.05–6780.07 mg/100 g) and V. myriocarpum (1506.47–6433.73 mg/100 g) than V. pyroliforme (49.54–121.97 mg/100 g). All extracts of V. cheiranthifolium (274.17–713.79 mg/100 g) and polar ones of V. myriocarpum (185.67–304.51 mg/100 g) accumulated higher chlorogenic acid content than V. pyroliforme extracts (36.33–112.56 mg/100 g). The latter species was dominated by luteolin-7-O-glucoside and apigenin-7-O-glucoside with highest content recorded from the hydromethanolic extract (639.70 and 196.14 mg/100 g respectively). Extracts of V. cheiranthifolium (46.15–48.74 mg TE/g) and V. myriocarpum (46.05–48.50 mg TE/g) exerted significantly higher scavenging activity than those from V. pyroliforme (12.77–34.64 mg TE/g). Highest significant anti-acetylcholinesterase activity was obtained by MeOH extract of V. pyroliforme (2.65 mg GALAE/g) and V. myriocarpum (2.57 mg GALAE/g). In conclusion, extracts from the three investigated Verbascum spp. can be a potential source of bioactive metabolites with interesting antioxidant and enzyme inhibition properties.

Changes in the chemical profile and bioactive potentialities of Kombucha fermented Salvia aegyptiaca tea

Kombucha is a traditionally non-alcoholic drink prepared by fermenting sweet-flavored black tea with tea fungus. In the present study, Salvia aegyptiaca tea was used as alternative substrate for kombucha fermentation due to its bioactivity which could improve the functional characteristics of kombucha. The prepared infusions (unfermented controls, without and with sugar) and fermented aqueous extracts were subjected to liquid-liquid extraction with ethyl acetate (EtOAc) and n-butanol (n-BuOH), sequentially, then compared in terms of their total phenolic content (TPC), antioxidant, anti-acetylcholinesterase (AChE), anti-inflammatory (anti-15-lipoxygenase), anti-xanthine oxidase (XOD) and cytotoxic activities. The kombucha beverage was obtained after longer period (11 days). Results indicated that fermentation reduced TPC in all extracts compared to unfermented samples (without and with sugar). The antioxidant capacity of S. aegyptiaca was enhanced by fermentation of n-BuOH (89%) and EtOAc (85%) extracts and inversely reduced in aqueous fraction. Nineteen phenolic compounds were identified and quantified using HPLC (high-performance liquid chromatography), whereas different aromatic compounds were detected using GC-MS (gas chromatography-mass spectrometry). The AChE, XOD and 15-lipoxygenase inhibitory effects as well as cytotoxic activity of all extracts were reduced by fermentation. The obtained results suggested that S. aegyptiaca tea is probably not suitable as substrate for kombucha production, as it can not be used as the only nitrogen source for tea fungus culture due to the low content of nitrogen in the leaves of the used plant.

Phenolic Compounds and Antioxidant and Anti-Enzymatic Activities of Selected Adaptogenic Plants from South America, Asia, and Africa.

Despite the fact that there are many studies related to the adaptogenic and pro-healthy activities of plant-based compounds, there are some adaptogenic plants whose activities are not fully known, especially those coming from the wild regions of Asia, Africa, and South America. The aim of these studies was to examine the contents of non-nutritional compounds, such as polyphenols, flavonoids, and phenolic acids in ten adaptogenic species (Astragalus membranaceus (AM), Uncaria rhynchophylla (UR), Polygonum multiflorum (PM), Angelica sinensis (AS), Andrographis paniculatea (AP), Tinospora cordifolia (TC), Uncaria tomentosa (UT), Pfaffia paniculate (PP), Sutherlandia frutescens (SF), and Rhaponticum carthamoides (RC)). Considering biological activity, their antioxidant (DPPH, ABTS, FRAP, and ferrous-ion-chelating ability assays), anti-acetylcholinesterase, anti-hyaluronidase, and anti-tyrosinase activities were evaluated. The richest in polyphenols, flavonoids, and phenolic acids was UR (327.78 mg GAE/g, 230.13 mg QE/g, and 81.03 mg CA/g, respectively). The highest inhibitions of acetylcholinesterase, hyaluronidase, and tyrosinase were observed for TC, UR, and PM, respectively. In the case of antioxidant properties, extract from PM appeared to most strongly reduce DPPH, extract from UR inhibited ABTS, and extract from SF showed the best chelating properties. It should be noted that a particularly interesting plant was Ulcaria rhynchophylla. The results mean that there were compounds in UR with broad biological activities, and this species should be explored in more detail. Additionally, our results justify the traditional use of these species in the nutripharmacological or ethnopharmacological care systems of different regions.

CHEMICAL COMPOSITION ANALYSIS AND EVALUATION OF ANTIOXIDANT, ANTIACETYLCHOLINESTERASE AND CYTOTOXICITY OF MURRAYA KOENIGII (L.) SPRENG FRUIT OIL

Plant derived essential oils are easily available source for healthcare purpose and it creates increased attention due to undesirable effects of chemically synthesized drugs. Murraya koenigii (L.) Spreng. raw fruit oil was extracted, and its chemical constituents was analyzed. Antioxidant and acetylcholinesterase inhibitory effect was tested under in vitro. MTT assay for evaluating cytotoxic effect on HeLa cells was done. β-phellandrene was identified as major compound in the extracted fruit oil. Scavenging of DPPH radical, inhibition of lipid peroxidation and protection of deoxyribose were found to be excellent. A dose dependent antiacetylcholinesterase activity of oil was observed with IC50 value as 448.12±0.02µg/mL. A significant growth inhibitory effect of oil on cervical cancer cells (HeLa) was measured with an IC50 value of 194.1±0.03µg/mL. Overall, the essential oil extracted from raw fruit of Murraya koenigii (L.) Spreng exhibited several biological properties, and it could be considered for plant-based medicine preparations.

Toxicity, repellency, and anti-cholinesterase activities of bioactive molecules from clove buds Syzygium aromaticum L. as an ecological alternative in the search for control Hyalomma scupense (Acari: Ixodidae)

IntroductionThe goal of the current study is to evaluate the acaricidal and repellent properties of the ethanolic extract, essential oil, and primary component eugenol from Syzygium aromaticum against Hyalomma scupense cattle ticks. Their potential mechanisms of action were also examined, using an in vitro assay. MethodsClove essential oil was extracted using hydrodistillation technique. Gas chromatography-mass spectrometry (GC-MS) was performed to identify the chemical composition of clove. To evaluate the adulticidal, ovicidal, larvicidal and repellent proprieties of clove essential oil, eugenol and ethanolic extract on H. scupense, in vitro assays were performed using the adult immersion test (AIT), the ovicidal test, the larval packet test (LPT), the filter paper test and anti-acetylcholinesterase (AChE) activity. ResultsAfter treatment, eugenol, the primary phytoconstituent of clove oil, which accounts for 97.66% of the whole oil, had 99.22% acaricide activity and inhibited egg hatching at a concentration of 10 mg/mL. Eugenol and clove essential oil showed potent adulticidal effect at high concentrations (10 mg/mL), achieving 100 and 93.76% mortality, respectively. The ethanolic extract exhibited moderate activity. At high concentration, the larvicidal activity of S. aromaticum oil, eugenol, and ethanolic extract were 100, 100, and 77.18%, respectively. In filter paper experiments, when tested at the concentration 5 mg/mL; eugenol showed the longest repellent effect up to 6 h. We also found that eugenol was the most active AChE inhibitor (IC50 = 0.178 mg/mL). Nevertheless, additional investigations are required to confirm the accurate mechanism and the relevance of clove in practical application. ConclusionOverall, our research indicated that, because its effectiveness as acaricide, S. aromaticum essential oil and its phytoconstituent eugenol may offer an alternative source for the control of H. scupense cattle ticks.

Synthesis of aurone sulfonate derivatives: Evaluation of their cholinesterase inhibition, neuroprotective effects, and expression of oxidative stress-related genes

A set of novel aurone derivatives, designed as A0-A7 and B1-B4, were synthesized to serve as acetylcholinesterase inhibitors. The Ellman's colorimetric method was utilized to measure the anticholinesterase activity of the synthesized compounds. The derivatives were then tested on human SH-SY5Y cells under an oxidative stress model induced by hydrogen peroxide (H2O2). Effects on cell viability, ROS levels, protein carbonyl content, and gene expression of NRF2 and phase II anti-oxidative enzymes were measured after 24 h. The study revealed that a most compounds demonstrated anti-acetylcholinesterase (AChE) activity within the micromolar or submicromolar range. Compound A4 exhibited the highest activity level with an IC50 value of 0.04 µM, among the compounds tested. Additionally, compound A2 protected SH-SY5Y cells from oxidative stress by elevating NRF2 gene expression.

A novel skeleton alkaloid from Portulaca oleracea L. and its bioactivities

A novel skeleton alkaloid was obtained from Portulaca oleracea L., which was identified as 10,11-dihydroxybenzo[5′,6′] pentaleno[1′,2′:3,4]pyrrolo[2,1-b]oxazol-7(11bH)-one, named oleracone M, and its structure was determined using UHPLC-ESI-QTOF/MS, 1D NMR and 2D NMR spectroscopy, and circular dichroism. Then the bioactivities of the compound were investigated including the anti-inflammatory, anti-acetylcholinesterase and antioxidant activities. The results showed that the novel skeleton alkaloid exhibited the potent effect on inhibiting the secretion of IL-1β at 10 μM, anticholinesterase activity with IC50 value of 49.58 μM, and antioxidant activity with IC50 value of 66.43 μM.

Synthesis, in vitro and in silico evaluation of new flavonoids-trifluoroacetylated amino acid conjugates as anti-acetylcholinesterase and anti-proliferative agents

A series of halogenated 3-hydroxyflavones (3HFs) (3a-3f) and their conjugates with two trifluoroacetylated amino acids, namely glycine and L-alanine, were synthesized and characterized by 1H NMR, 13C NMR and ESI-HRMS. All the compounds were evaluated for their ability to inhibit the acetylcholinesterase enzyme and for their anti-proliferative effect against MCF-7, HCT-116 and OVCAR-3 cancer cell lines by standard MTT assay. Most of 3HFs-amino acids conjugates demonstrated promising cytotoxic activities, significantly higher than the corresponding 3HFs. Among them, compounds 8f and 9a showed the best cytotoxic activity against MCF-7 (IC50 = 5.5 and 5.3 µM, respectively), HCT-116 (IC50 = 6.2 and 5.5 µM, respectively) and OVCAR-3 (IC50 = 9.2 and 8.9 µM, respectively). The derivatives 9c and 9b exhibited the highest anti-acetylcholinesterase activity with IC50 values of 50.1 and 55.2 µM, respectively. The structure-activity relationship (SAR) is discussed based on molecular docking simulations.