Anti-acetylcholinesterase Activity Research Articles

Phlegcarines A-C, three Lycopodium alkaloids from Phlegmariurus carinatus (Desv. ex Poir.) Ching

Three undescribed Lycopodium alkaloids, phlegcarines A-C, along with nine known alkaloids, were isolated from the aerial parts of a gardening clubmoss Phlegmariurus carinatus (Desv. ex Poir.) Ching. Phlegcarine A is an undescribed Lycopodium alkaloid possessing an unprecedented 5/9/6/6 fused-tetracyclic ring system consisting of an oxa-cyclononanone, a piperidine, a methylcyclohaxane and an oxazolidine. Phlegcarine B is the first N-chloromethyl piperidinium Lycopodium alkaloid of (+)-lycoflexine. The semi-synthesis of phlegcarine B was investigated from (+)-fawcettimine. Phlegcarine C, an undescribed epimer of 12-epilycodoline, is a rare lycopodine-type alkaloid with β-oriented H-4. Transformation of phlegcarine C and lycodoline to 12-epilycopodine N-oxide via keto-enol tautomerization was investigated using m-CPBA. The structural assignments were established through comprehensive spectroscopic techniques and chemical correlations. Phlegcarines A-C were assayed for their anti-acetylcholinesterase activity, but none of them exhibited biological activity more potent than that of huperzine A.

Antioxidant and enzyme inhibition activities of Spartium junceum with HPLC-DAD profiling

Spartium junceum L., a Fabaceae plant, is commonly known as Spanish broom and cultivated in the Mediterranean regions. This study aimed to investigate the chemical profiles and antioxidant and different enzyme inhibitory activities of methanol, ethanol and aqueous extracts obtained from flowers and stems of S. junceum. Also, their phenolic compositions were analyzed by high-performance liquid chromatography with a diode-array detector (HPLC-DAD). The aqueous extract of stems showed the highest phenolic content (63.94 mg gallic acid equivalents/g), while the aqueous extract of stems contained the highest flavonoid content (61.33 mg quercetin equivalents/g). The stem water extract demonstrated the highest 2,2′-diphenyl-1-picrylhydrazyl radical-scavenging activity (IC50: 2327 μg/ml), while the stem water extract exhibited a strong 2,2′-azino-di(3-ethylbenzothiazoline-6-sulfonic acid) radical-scavenging activity (IC50: 91.80 ± 0.90 μg/ml). The tested extracts differed greatly in terms of enzyme inhibition activity. The stem water extract showed the highest anti-acetylcholinesterase activity (IC50: 46.69 ± 1.66 μg/ml); however, the stem methanol extract exhibited a strong anti-butyrylcholinesterase activity (IC50: 76.39 ± 0.27 μg/ml). The flower methanol extract was the most active against the α-glucosidase enzyme (IC50: 296.7 ± 3.77 μg/ml). All extracts showed low activities against α-amylase and tyrosinase enzymes. The evaluation of the biological activity results provides evidence for bioactivity-guided isolation studies on the active extracts of this plant.

Identification of Antioxidants and Acetylcholinesterase Inhibitors from Hapaline benthamiana Schott. Using at Line LC-ESI-QTOF MS/MS

In this work, total phenolics, total flavonoids, antioxidant activity, and acetylcholinesterase inhibition potency of Hapaline benthamiana schott are reported. In addition, the investigation of antioxidant and anti-acetylcholinesterase compounds of this plant coupled to the at line-LC-ESI-QTOF-MS/MS technique is introduced for the first time. The results show that the methanolic extract contains the highest amount of total phenolics, total flavonoids, antioxidant activity, and acetylcholinesterase inhibition activity. The at line-LC-ESI-QTOF-MS/MS technique has provided information on the biological activity of each compound while mass spectrometry provided information on their molecular weights. Based on their mass spectra, 53 compounds were identified with most of them being phenolic, flavonoid, and glycolipid compounds. Seventeen compounds exhibited a strong antioxidant activity ranging between 51.52 - 63.58 % inhibition whereas one compound, namely septentriodine, showed a strong acetylcholinesterase inhibitory effect of more than 50 %. This study indicates that Hapaline benthamiana schott is a source of active compounds containing antioxidant and anti-acetylcholinesterase activities with health benefits. In addition, at line-LC-ESI-QTOF-MS/MS has been shown to be an effective technique for the rapid and simultaneous analyses of antioxidant and anti-acetylcholinesterase compounds in plant extracts. HIGHLIGHTS Investigation of antioxidants and acetylcholinesterase inhibitors from Hapaline benthamiana Schott coupled to at line-LC-ESI-QTOF-MS/MS technique is reported for the first time Fifty-three compounds from methanolic extract were successfully identified Eighteen compounds exhibited strong biological activity This technique is a rapid and valuable tool for the identification of lead compounds in complex extracts and for the investigation of their bioactivity GRAPHICAL ABSTRACT

Variation in essential oil composition within and among Tunisian Thymus algeriensis Boiss et Reut. (Lamiaceae) populations: Effect of ecological factors and incidence on antiacetylcholinesterase and antioxidant activities

The variation of the essential oil composition of fourteen Tunisian Thymus algeriensis populations and their antioxidant and antiacetylcholinesterase activities were assessed. At the species level, α-pinene, 1,8-cineole, camphor, caryophyllene oxide and carvacrol were the main compounds. Significant variation in the essential oil composition was observed between populations according to ecological factors. Six chemotypes were revealed (1,8-cineole-β-panasinsene/1,8-cineole/caryophyllene oxide/1,8-cineole-camphor-caryophyllene oxide/1,8-cineole-camphor-caryophyllene oxide-terpenyl acetate/carvacrol) with the distinction of upper arid populations (Ta 13 and Ta 14) with the dominance of carvacrol chemotype. The occurrence of the carvacrol was positively correlated to the evapotranspiration, summer drought stress and the temperature of the warmest months of the year.High chemical intrapopulation variability was also observed, revealing the presence of seven chemotypes (carvacrol/terpenyl acetate/caryophyllene oxide/linalool-linalyl acetate/1,8-cineole-β-panasinsene/1,8-cineole/1,8-cineole-camphor). The level of antioxidant and anti-acetylcholinesterase activity was linked to their chemical composition difference. The best activities were revealed for populations Ta 13 and Ta 14 from the most arid zones, characterized by their carvacrol richness.

In Vitro Screening for Anti-Acetylcholinesterase and Antioxidant Activities of Hottonia palustris L. Extracts and Their Unusual Flavonoids.

Hottonia palustris L. is from the genus Hottonia (Primulaceae), and the understanding of its phytochemical and pharmacological properties is limited. In this study, the use of chromatographic techniques led to the isolation of a further eleven compounds, including three new flavonoids: 2',5-dihydroxyflavone 2'-O-β-glucopyranoside, 5,6-dihydroxyflavone 6-O-(6"-O-glucopyranosyl)-β-glucopyranoside (hottonioside A), and 4',5,7-trihydroxyflavone 7-O-(2"-O-β-glucuronide)-β-glucopyranoside. Their structures were determined using extensive 1D and 2D NMR data and mass spectrometry (HRMS). The qualitative assessment of the chemical composition of the investigated extracts and fractions was performed using the LC-HRMS technique. Furthermore, the antioxidant potential of extracts, fractions, and compounds and their ability to inhibit acetylcholinesterase were also evaluated. Thus, we may conclude that the observed biological effects are the result of the presence of many biologically active compounds, of which dibenzoylmethane is the most active. Therefore, H. palustris is a source of substances with desirable properties in the prevention and treatment of neurodegenerative diseases.

Divulging the anti-acetylcholinesterase activity of Colletotrichum lentis strain KU1 extract as sustainable AChE active site inhibitors.

Alzheimer's disease (AD), also called senile dementia is a neurodegenerative disease seen commonly in the elderly and is characterised by the formation of β-amyloid plaques and neurofibrillary tangles (NFT). Though a complete understanding of the disease is lacking, recent studies showed the role of the enzyme acetylcholinesterase (AChE) in pathogenesis. Finding new lead compounds from natural sources has always been a quest for researchers. Endophytic fungi are a set of microbes that reside within plants without causing any harm. This study focuses on screening endophytes for the production of active acetylcholinesterase inhibitors. Five endophytic fungi were isolated from Catharanthus roseus and screened for AChE inhibitory activity. Three isolates were found to inhibit AChE inhibitory activity and were distinguished based on molecular and microscopic methods. The mycelial extract was taken for the bioassay-guided column chromatography and TLC was performed on the active fraction. The GC-MS and NMR analysis identified the active compounds in the extract as 9-hexadecen-1-ol and erucamide. Molecular docking studies revealed that the compounds are thermodynamically feasible and have significant glide scores. Computational studies revealed that the hydroxyl group of 9-hexadecen-1-ol forms a hydrogen bond with Ser 293 in the active site of AChE, whereas the active site interactions were predominantly hydrophobic in the case of erucamide and are reflected in AChE inhibition assays.

Structural Elucidation and Total Synthesis for the Pair of Unprecedented Polypyridines with Anti-AChE and HIV-1 Protease Activities from Alangium chinense.

Unlike reported pyridine hybrids, 2S (1a) and 2R-alanginenmine A (1b) from Alangium chinense featuring an unprecedented piperidine-bridged polypyridine skeleton represented a pair of alkaloid subtypes with a unique multiple pyridine scaffold. Enlightened by the rare structural characteristics and possible biosynthetic pathway, (±)-alanginenmine A (1) have been achieved in ideal yield by gram-class total synthesis with four steps. In addition, both compounds 1a and 1b exhibited anti-acetylcholinesterase (AChE) and HIV-1 protease activities in the biological activity evaluation. Further, molecular docking was investigated for the mechanism of action between the isolated compounds and HIV-1 protease. The stronger Coulomb interactions and van der Waals interaction, as well as the hydrogen bond interactions of 1a, might be the main cause for its better anti-HIV-1 protease activity than 1b. This work provided a comprehensive research including natural product discovery, bioactivity evaluation, and total synthesis for the new type of leading anti-HIV-1 protease.

Anticholinesterase activity of Areca Catechu: In Vitro and in silico green synthesis approach in search for therapeutic agents against Alzheimer's disease.

For many years, the primary focus has been on finding effective treatments for Alzheimer's disease (AD), which has led to the identification of promising therapeutic targets. The necessity for AD stage-dependent optimal settings necessitated a herbal therapy strategy. The plant species Areca Catechu L. (AC) was selected based on the traditional uses against CNS-related diseases. AC leaf extract were prepared using a Soxhlet extraction method and hydroxyapatite nanoparticles (HAp-NPs) were synthesized from the same (AC-HAp-NPs). Powder X-ray diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and fourier transform infrared spectroscopy (FTIR) were used to confirm the structure and morphology of the as-prepared AC-HAp-NPs. The crystalline character of the AC-HAp-NPs was visible in the XRD pattern. The synthesized material was found to be nanoflake, with an average diameter of 15-20nm, according to SEM analysis. The TEM and SAED pictures also revealed the form and size of AC-HAp-NPs. In vitro anti-acetylcholinesterase and butyrylcholinesterase (AChE and BChE) activities of hydroxyapatite nanoparticles produced from an AC leaf extract was tested in this study. When compared to control, AC-HAp-NPs had higher anti-AChE and BChE activity. The anti-acetylcholinesterase action of phytoconstituents generated from AC leaf extract was mediated by 4AQD and 4EY7, according to a mechanistic study conducted utilizing in silico research. The global and local descriptors, which are the underpinnings of Conceptual Density Functional Theory (CDFT), have been predicted through the MN12SX/Def2TZVP/H2O model chemistry to help in the comprehension of the chemical reactivity properties of the five ligands considered in this study. The CDFT experiments are supplemented by the calculation of several useful calculated pharmacokinetics indices, their expected biological targets connected to the bioavailability of the five ligands in order to further the goal of studying their bioactivity.

Diverse guaiane-type sesquiterpenoids from the root of Daphne genkwa based on molecular networking

Eleven undescribed guaiane-type sesquiterpenoids, named daphnegenols A-K (1–11) and a known analog (12) were targeted for isolation from the root of Daphne genkwa by LC-MS/MS-based molecular networking. Their diverse structures were elucidated through extensive spectroscopic methods, quantum chemical calculation and X-ray single crystal diffraction, including 5/7 bicycle, 5/6/7 tricycles and 5/6/5 tricycles guaiane-type sesquiterpenoid. Daphnegenol A (1) possessed a rare six membered oxyheterocyclic ring which was constructed by oxidation and cyclization at C-1 and C-11. The anti-acetylcholinesterase and anti-neuroinflammatory activities of compounds 1–12 were measured.

Neuroprotective Effect of Artichoke-Based Nanoformulation in Sporadic Alzheimer's Disease Mouse Model: Focus on Antioxidant, Anti-Inflammatory, and Amyloidogenic Pathways.

The vast socio-economic impact of Alzheimer’s disease (AD) has prompted the search for new neuroprotective agents with good tolerability and safety profile. With its outstanding role as antioxidant and anti-inflammatory, alongside its anti-acetylcholinesterase activity, the artichoke can be implemented in a multi-targeted approach in AD therapy. Moreover, artichoke agricultural wastes can represent according to the current United Nations Sustainable Development goals an opportunity to produce medicinally valuable phenolic-rich extracts. In this context, the UPLC-ESI-MS/MS phytochemical characterization of artichoke bracts extract revealed the presence of mono- and di-caffeoylquinic acids and apigenin, luteolin, and kaempferol O-glycosides with remarkable total phenolics and flavonoids contents. A broad antioxidant spectrum was established in vitro. Artichoke-loaded, chitosan-coated, solid lipid nanoparticles (SLNs) were prepared and characterized for their size, zeta potential, morphology, entrapment efficiency, release, and ex vivo permeation and showed suitable colloidal characteristics, a controlled release profile, and promising ex vivo permeation, indicating possibly better physicochemical and biopharmaceutical parameters than free artichoke extract. The anti-Alzheimer potential of the extract and prepared SLNs was assessed in vivo in streptozotocin-induced sporadic Alzheimer mice. A great improvement in cognitive functions and spatial memory recovery, in addition to a marked reduction of the inflammatory biomarker TNF-α, β-amyloid, and tau protein levels, were observed. Significant neuroprotective efficacy in dentate Gyrus sub-regions was achieved in mice treated with free artichoke extract and to a significantly higher extent with artichoke-loaded SLNs. The results clarify the strong potential of artichoke bracts extract as a botanical anti-AD drug and will contribute to altering the future medicinal outlook of artichoke bracts previously regarded as agro-industrial waste.

Elsholtzia ciliata (Thunb.) Hyland: A Review of Phytochemistry and Pharmacology.

In this paper, the confusion of the sources of medicinal materials was briefly expounded, and the differences among the varieties were pointed out. At the same time, the chemical components and pharmacological properties of Elsholtzia ciliata (Thunb.) Hyland (E. ciliata) were reviewed. The structures of 352 compounds that have been identified are listed. These mainly include flavonoids, terpenoids, phenylpropanoids, alkaloids, and other chemical components. They have antioxidant, anti-inflammatory, antimicrobial, insecticidal, antiviral, hypolipidemic, hypoglycemic, analgesic, antiarrhythmic, antitumor, antiacetylcholinesterase, and immunoregulator activities. At present, there are many researches using essential oil and alcohol extract, and the researches on antioxidant, anti-inflammatory, anti-microbial, and other pharmacological activities are relatively mature. This paper aims to summarize the existing research, update the research progress regarding the phytochemicals and pharmacology of E. ciliate, and to provide convenience for subsequent research.

New carbazol derivatives containing 1,2,4-triazole: Synthesis, characterization, DFT study, acetylcholinesterase activity and docking study

Carbazol derivatives, 4-(((9-ethyl-9H-carbazol-3-yl)methylene)amino)-5-methyl-2,4-dihydro-3H-1,2,4-triazole-3-one (3) and 5-benzyl-4-(((9-ethyl-9H-carbazol-3-yl) methylene) amino)-2,4-dihydro-3H-1,2,4-triazole-3-one (4), were synthesized. Compounds 3 and 4 were characterized by The Fourier transform infrared (FTIR), proton and carbon-13 nuclear magnetic resonance (1H- and 13C- NMR) spectroscopic methods. Density Functional Theory (DFT) calculations for compounds 3 and 4 were performed at B3LYP/6–311++G(d,p) level. Optimized geometry, IR and NMR parameters of compounds 3 and 4 were obtained. The in vitro anti-acetylcholinesterase activity of the compounds were examinated. In addition, Compounds 3 and 4 were tested to determine possible interactions against human acetylcholinesterase by in silico analysis.

Insight into Isolation and Characterization of Phenolic Compounds from Hawthorn (Crataegus pinnatifida Bge.) with Antioxidant, Anti-Acetylcholinesterase, and Neuroprotective Activities.

Recent epidemiologic studies have demonstrated a link between the consumption of daily functional fruits rich in phenols and the prevention of disease for neurodegenerative disorders. Hawthorn products are derived from the functional fruit hawthorn, which is rich in phenols and has been used around the world for centuries. In order to explore the phenolic components in hawthorn, the investigation of the ethanol extract led to the separation of five new phenol compounds (1a/1b, 2-4), including one pair of enantiomers (1a/1b), along with seven disclosed analogs (5-11). Their structures were elucidated based on extensive spectroscopic analyses and electronic circular dichroism (ECD). The compounds (1-11) were tested for antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonicacid) (ABTS), and ferric reducing antioxidant power (FRAP) methods. Apart from that, monomeric compounds 2, 4, and 6 exhibited more potent protective capabilities against H2O2 (hydrogen peroxide)-induced SH-SY5Y cells. Meanwhile, electronic analyses were performed using the highest occupied molecular orbital (HOMO), and the lowest unoccupied molecular orbital (LUMO) to analyze compounds 2, 4, and 6. Furthermore, compounds (1-11) measured acetylcholinesterase (AChE) inhibitory activities, and 2, 4, and 6 possessed greater AChE inhibitory activity than donepezil. At the same time, molecular docking was used to investigate the possible mechanism of the interaction between active compounds (2, 4, and 6) and AChE.

Novel 3-phenyl-1- (alkylphenyl)-9-oxa-4-azaphenanthren-10-ones as inhibitors of some enzymes: synthesis, characterization, biological evaluation and molecular docking studies

A series of novel 3-phenyl-1-(alkylphenyl)-9-oxa-4-azaphenanthren-10-ones and (E)-1-phenyl-3-(aryl)prop-2-en-1-ones were synthesized and characterized by IR, 1H NMR, 13C spectroscopy and elemental analysis. The synthesized Compounds 5a–f were subjected to molecular docking simulation with three proteins, namely, tyrosyl-tRNA synthetase, heme oxygenase 1 and acetylcholinesterase to evaluate the antibacterial, antioxidant and acetylcholinesterase inhibition, respectively. Moreover, the docked poses of all compounds inside the proteins were subjected to further dynamic simulation through the calculation of the binding free energy using MM-GBSA analysis. Compound 5d exhibits high potential inhibition against antibacterial, antioxidant and acetylcholinesterase activities. Compounds 3d, 3f, 5a and 5d recorded an important scavenging activity in DPPH and ABTS assays. Investigation of the anti-acetylcholinesterase activity of the synthesized compounds showed that Compounds 5a and 3d are the most potent inhibitors against AchE, with percent inhibition values of 38 and 30%, respectively. Communicated by Ramaswamy H. Sarma

Investigations of specialised metabolites of endophyte Diaporthe destruens hosted in Illigera orbiculata C. Y. Wu

A chemical investigation of the endophytic fungus Diaporthe destruens from the Hernandiaceae plant Illigera orbiculata C. Y. Wu collected from southern Yunnan Province, China, led to the isolation of six undescribed compounds, including two azaphilone analogs, which are a pair of epimers (13R-hydroxy-chermesinone A and 13S-hydroxy-chermesinone A); a pyrrole derivative (1-(4-(methoxymethyl)-1H-pyrrol-3-yl)ethan-1-one); an isoindolone derivative (4-hydroxy-6-methoxyisoindolin-1-one); a benzylbenzene derivative (destruensine A) and a conjectural fragment of polyketide ((2R,4R)-2-(methoxymethyl)pentane-1,4-diol) along with nine known compounds. Their structures were elucidated by spectroscopic methods and HRESIMS, and the absolute configurations were further confirmed by electronic circular dichroism (ECD) and chemical derivatization. The antimicrobial activities, anti-acetylcholinesterase activities, antiproliferation, and NO production inhibitory effects of compounds 1–15 were evaluated.

Two New Picoline-Derived Meroterpenoids with Anti-Acetylcholinesterase Activity from Ascidian-Derived Fungus Amphichorda felina.

Amphichoterpenoids D (1) and E (2), two new picoline-derived meroterpenoids with a rare 6/6/6 tricyclic pyrano[3,2-c]pyridinyl-γ-pyranone scaffold, were isolated from the ascidian-derived fungus Amphichorda felina SYSU-MS7908. Their structures, including the absolute configurations, were established by extensive spectroscopic methods (1D and 2D NMR and high-resolution mass spectrometry) and ECD calculations. Compounds 1 and 2 showed anti-acetylcholinesterase (anti-AChE) activities with IC50 values of 12.5 μM and 11.6 μM, respectively. The binding interactions between 1, 2, and AChE were investigated using molecular docking analyses.

Which Extraction Solvents and Methods Are More Effective in Terms of Chemical Composition and Biological Activity of Alceafasciculiflora from Turkey?

The bioactive content, antioxidant properties, and enzyme inhibition properties of extracts of Alcea fasciculiflora from Turkey prepared with different solvents (water, methanol, ethyl acetate) and extraction methods (maceration, soxhlet, homogenizer assisted extraction, and ultrasound assisted extraction) were examined in this study. UHPLC-HRMS analysis detected or annotated a total of 50 compounds in A. fasciculiflora extracts, including 18 hydroxybenzoic and hydroxycinnamic acids, 7 Hexaric acids, 7 Coumarins, 15 Flavonoids, and 3 hydroxycinnamic acid amides. The extracts had phenolic and flavonoid levels ranging from 14.25 to 24.87 mg GAE/g and 1.68 to 25.26 mg RE/g, respectively, in the analysis. Both DPPH and ABTS tests revealed radical scavenging capabilities (between 2.63 and 35.33 mg TE/g and between 13.46 and 76.27 mg TE/g, respectively). The extracts had reducing properties (CUPRAC: 40.38–78 TE/g and FRAP: 17.51–42.58 TE/g). The extracts showed metal chelating activity (18.28–46.71 mg EDTAE/g) as well as total antioxidant capacity (phosphomolybdenum test) (0.90–2.12 mmol TE/g). DPPH, ABTS, FRAP, and metal chelating tests indicated the water extracts to be the best antioxidants, while the ethyl acetate extracts had the highest overall antioxidant capacity regardless of the extraction technique. Furthermore, anti-acetylcholinesterase activity was identified in all extracts (0.17–2.80 mg GALAE/g). The water extracts and the ultrasound-assisted ethyl acetate extract were inert against butyrylcholinesterase, but the other extracts showed anti-butyrylcholinesterase activity (1.17–5.80 mg GALAE/g). Tyrosine inhibitory action was identified in all extracts (1.79–58.93 mg KAE/g), with the most effective methanolic extracts. Only the ethyl acetate and methanolic extracts produced by maceration and homogenizer aided extraction showed glucosidase inhibition (0.11–1.11 mmol ACAE/g). These findings showed the overall bioactivity of the different extracts of A. fasciculiflora and provided an overview of the combination of solvent type and extraction method that could yield bioactive profile and pharmacological properties of interest and hence, could be a useful reference for future studies on this species.

Identification of potential anti‐Alzheimer agents from Pistacia atlantica Desf. galls using UPLC fingerprinting, chemometrics, and molecular docking analyses

The purpose of this study was to test extracts from P. atlantica Desf. galls (PAG) for anti-acetylcholinesterase (AChE) and anti-butyrylcholinesterase (BuChE) activity, and investigate the influence of harvesting time, plant gender, and growing location on such activity. The IC50 values of PAG extracts ranged from 56.42-68.94 μg/ml to 82.43-95.81 μg/ml, respectively. Our findings revealed that the anti-AChE/BuChE activity of PAG extracts was relatively more influenced by the time of harvest than by plant gender and growing location. A combination of UPLC fingerprinting and chemometrics using partial least squares regression analysis identified the presence of two phenolic compounds, namely methyl gallate and digalloylquinic, as responsible for the anti-AChE/BuChE activity of PAG extracts. A molecular docking study further confirmed that both compounds were able to bind to AChE and BuChE and interact with key residues of the active sites of these enzymes. Practical applications Pistacia atlantica Desf. is an important medicinal plant whose galls are traditionally used in many Mediterranean countries for the treatment of Alzheimer’s disease. The combination of fingerprint technology with chemometrical approaches in this study enabled the putative identification of metabolites in P. atlantica gall extracts responsible for anticholinesterase activity. This investigation highlights the potential of P. atlantica galls as a promising source for the discovery and development of new anti-Alzheimer agents.

Access to new phosphonate- and imidazolidine-benzopyrimidinone derivatives as antityrosinase and anti-acetylcholinesterase agents: Design, synthesis and molecular docking

To discover new acetylcholinesterase and tyrosinase inhibitors, a series of dialkyl phosphonate-benzopyrimidinones 4a-b was prepared via Michaelis-Arbuzov rearrangement (Arbusov reaction) of benzopyrimidinone chloride 2 with trialkyl phosphate, as well as a series of imidazolidine-benzopyrimidinone derivatives 5a-g synthesized by Mannich reaction of 2-((arylamino)methyl) benzopyrimidin-4(3H)-one 3 with formaldehyde. The structures of the new target compounds were investigated by 1H NMR, 13C NMR and ESI-HRMS. All synthesized compounds were evaluated for their anti-acetylcholinesterase and antityrosinase activities. Compounds 5f, 3g and 4b showed the highest tyrosinase inhibition and compounds 3g, 3d and 5g were found to be the most anti-acetylcholinesterase agents. Moreover, structure activity relationship (SAR) was discussed for all synthesized compounds and the interaction modes of the most potent inhibitors were confirmed through molecular docking studies.

Laurel essential oil: biological activities and application for semolina preservation against the red flour beetle Tribolium castaneum (Tenebrionidae)

ABSTRACT The phytochemical composition of Laurus nobilis essential oil and their anticholinesterase, antioxidant, and insecticidal potential were studied. Also, the oil volatile fraction was compared in semolina at the beginning and after storage periods. For that, a headspace solid-phase-microextraction analysis (HS-SPME) coupled with gas chromatography and mass spectrometry was undertaken. Significant quantitative and qualitative differences of the oil volatile fraction were detected according to storage periods and occupation space ratios. Additionally, anti-acetylcholinesterase activity of L. nobilis oil against T. castaneum adults was evaluated. Results revealed that insecticide activity varied according to storage duration and occupation space. Besides, the oil acts on acetylcholine hydrolysis by inhibiting the activity of acetylcholinesterase. These results highlighted that L. nobilis essential oil may be recommended as an eco-friendly alternative for preserving semolina during storage.