ACETYLCHOLINESTERASE INHIBITORY ACTIVITY OF DOREMA AMMONIACUM GUM EXTRACTS AND MOLECULAR DOCKING STUDIES

ACETYLCHOLINESTERASE  INHIBITORY  ACTIVITY  OF  DOREMA AMMONIACUM  GUM  EXTRACTS  AND  MOLECULAR  DOCKING  STUDIES

M. Mazaheritehrani ^{* 1, 2}, R. Hosseinzadeh ¹, M. Mohadjerani ³, M. Tajbakhsh ¹ and S. N. Ebrahimi ⁴

Department of Organic Chemistry ¹, Faculty of Chemistry, Department of Molecular and Cell Biology ³, Faculty of Basic Science, University of Mazandaran, Babolsar, Iran.

Department of Chemistry ², Faculty of Science, Golestan University, Gorgan, Iran.

Department of Phytochemistry ⁴, Medicinal Plants and Drugs Research Institute, Shahid Beheshti University, G. C., Evin, Tehran, Iran.

ABSTRACT: Ammoniacum gum is traditionally used as an expectorant, stimulant, antispasmodic, catarrh, asthma, chronic bronchitis, and enlargement of liver and spleen in Medicine. The Soxhlet extraction of the oleo gum resin of D. ammoniacum was carried out with organic solvents including hexane, dichloromethane, chloroform, ethyl acetate, and methanol. The screening of the anti-alzheimer activity of the extracts was measured by acetylcholinesterase (AChE) inhibitory activity, and the hexane (IC₅₀ = 32.34 μg/ml) and chloroform (IC₅₀ = 43.5 μg/ml) extract performed highest activity. A profiling experiment of the chloroform extract conducted by LC-MS and literature resources suggested six potential biologically active compounds including doremone A (1), kopetdaghin E (2), dshamirone (3), kopetdaghin D (4), kopetdaghin C (5), and ammodoremine (6). To confirm the responsibility of these compounds for the observed AChE inhibitory activity, the molecular docking studies of these compounds were performed with AChE enzyme which indicated that these compounds show higher AChE inhibitory activity than galantamine as positive control. The molecular docking study was carried out using Glide.

Dorema ammoniacum, Acetylcholinesterase inhibition, LC–MS, Docking study

INTRODUCTION: Nature is a rich source of medicinal compounds, some of which are stored in plants and possess numerous biological effects. Medicinal plants are good sources of biologically active compounds showing antioxidant, anti-bacterial and anti-acetylcholinesterase activities ^1-4. One of the most intensively studied subjects in the field of phytochemistry (medicinal plants) is the investigation of plants with an anti-cholinesterase action ^{5, 6, 7}.

Alzheimer’s disease (AD) is the most common cause of senile dementia in later life ^{8, 9, 10}. A loss of acetylcholine (ACh) is considered to play a vital role in the learning and memory deterioration of AD patients ^{11, 12}. Dorema ammoniacum D. Don commonly known as Ushaq (local Persian names of Kandal, Vasha or Koma-kandal) is a monocarpic plant that is native to the arid and semi-arid regions of Iran such as Yazd, Isfahan and Semnan ^{13, 14}. In Unani System of Medicine, ammoniacum gum is an antispasmodic which is also used in treating enlargement of the liver, chronic bronchitis, and persistent coughing and asthma ^{15, 16}. It has been used in treatment of spastic pains, gastric disorders, intestinal parasitic infections, and skin inflammations and as analgesic, stimulant, expectorant and laxative ^{17, 18, 19}.

This gum is exudated from the pores of stems, leaves, and petioles of the flowering and fruiting plants of Dorema ammoniacum ^{20, 21}. The acetylcholinesterase (AChE) inhibitory activity of dichloromethane extract of the gum resin was also reported ^{22, 23}. In the present study, the anti-Alzheimer activity of methanol, chloroform, hexane and ethyl acetate extracts of oleo gum resin from Dorema ammoniacum was investigated using microplate colorimetric assay. Additionally, the major constituents of the chloroform extract were determined by LC-PDA-MS analysis and their activity against the cholinergic enzyme viz. AChE was analyzed by molecular docking methods.

MATERIAL AND METHODS:

Chemicals: Acetylcholinesterase (AChE), acetylthiocholine iodide (ATCI), 5,5′‐dithio-bis‐(2‐nitrobenzoic acid) (DTNB), Tris‐HCl, bovine serum albumin (BSA), and all the chemicals used in the acetylcholinesterase inhibitory assays were purchased from Sigma-Aldrich Chemie GmbH, Germany. Two different buffer systems were used. Buffer A: 50 mm Tris‐HCl, pH 7.9 containing 0.1% BSA; Buffer B: 50 mm Tris‐HCl, pH 7.9 containing 0.1 M NaCl and 0.02 M MgCl₂.6H₂O.

Extraction: Oleo gum resin of the species Dorema ammoniacum was collected from the desert of Shahroud (35° 25' 32.01'' N, 55° 00' 32.46'' E) in Semnan province, Iran. A voucher specimen of the plant has been retained in the herbarium of Science Faculty, Golestan University, Gorgan, Iran (voucher number 6251). Extraction was done using Soxhlet extractor with organic solvents of different polarity including hexane, chloroform, ethyl acetate, and methanol. In each experiment, 250 ml of solvent and 25 g of sample were used. The total extraction process was completed within 4 - 8 h. After filtration and evaporation of the solvents under reduced pressure, 11.5, 9.1, 1.1 and 12.2 g of brown residues were obtained from ethyl acetate, methanol, hexane, and chloroform, respectively.

Acetylcholinesterase Activity: The AChE inhibitory activities of the ammoniacum gum extracts were measured by Ellman’s method with the aid of a quantitative colorimetric assay 24, 25. A mixture of ATCI (25 μl, 15 mm), DTNB (125 μl, 3 mm in buffer B), buffer A (50 μl) and sample (25 μl, 10 mg/ml in DMSO diluted with buffer A to a concentration of 1 mg/ml) was placed in a 96‐well plate.  The optical density was measured at 405 nm, five times every 15 s. Then AChE (25 μl, 0.22 U/ml in buffer A) was added followed by incubation at 25 °C for 10 min. Shortly following this, the absorbance was measured eight times every 15 s again. The hydrolysis of acetylthiocholine iodide was monitored as a result of the reaction of DTNB with thiocholines. Repetition of the assay was done three times for each concentration. The assay was validated by measurement of different concentrations of galantamine as a positive control and the percentage of inhibition was calculated by comparing the absorbance of the sample with a blank. The inhibition rate of the samples on acetylcholinesterase was calculated by the following formula:

% Inhibition = [(Absorbance control – Absorbance sample) / Absorbance control] × 100

The IC₅₀ values were calculated from inhibition curves (inhibitor concentration vs. percent of inhibition). The IC₅₀ value of galantamine was determined as 2.5 ± 0.20 μl. Tacrine, donepezil, rivastigmine, and galantamine are AChE inhibitors used as anti- Alzheimer’s disease (AD) drugs ^{26, 27}.

LC-PDA-MS: LC-PDA-MS analysis was carried out on a Shimadzu Prominence high-performance liquid chromatography (HPLC) system which comprised an LC-20 AD binary pump, CTO-20AC column thermostat, SDP-M20A PDA detector, CBM-20A system controller, and coupled to an LCMS-8030 triple quadrupole mass spectrometer equipped with an electrospray ionization source (ESI). Operating conditions were: capillary voltage, 4.5 V; desolvation line temperature, 250 °C; heat block temperature, 500 °C; drying gas (nitrogen) flow, 15 L min^-1; nebulizing gas (nitrogen) flow, 3 L min^-1. Full-scan (160 - 1500) was carried out with 6000 u/sec scan speed and 0.150 s per event time for data acquisition in both positive and negative ionization modes. LC separation was performed on a C18 Sun Fire column (3.5 μm, 3 × 150 mm i.d., Waters) equipped with a guard column (3 × 20 mm i.d.). HPLC solvents both contained formic acid (0.1%, v/v), and the flow rate was set to 0.4 ml min^-1. The following gradient was used: an isocratic step at 50% A for 5 min, the concentration of solvent B increased up to 100 % in 25 min. The mobile phase was kept at this concentration for 15 min, then decreased to 40% A for 5 min. Data acquisition was done with lab solutions software (Shimadzu). The mobile phase consisted of 10 µl water (A) and acetonitrile (B).

Molecular Docking: Since the drug discovery process of AD is laborious and expensive ^{28, 29} thus, structure-based drug discovery has gained importance ^{30 - 33}. In the present study the molecular docking study was used to investigate the binding affinity of identified compounds to the active site of AChE. For this purpose, docking study was carried out using Glide (Schrodinger package 2016-2). The AChE enzyme protein structure file (PDB ID: 1EVE) was taken from the PDB (Protein Data Bank) and edited using protein preparation on Maestro 10.6, where all cofactors, water molecules and co-crystallized ligands were removed from the protein structure before docking ^{34, 35}.

Partial atomic charges were assigned according to the Optimized Potentials for Liquid Simulations (OPLS3) force field. The Ramachandran diagram was used to clarify the applicability of the prepared protein for further docking analysis. The grid box was centered at particular residues of the protein and was generated with Grid generation application with coordinates x = -2.71, y = 28.02, z = 31.71. The dimensions of the active site box were set at 20 × 20 × 20 Å 36. Compounds were docked inside a sphere with a 15 Å radius centered at the largest cavity detected by the program.

RESULTS AND DISCUSSION:

Acetylcholinesterase Inhibitory Assay: In the present study, five extracts of ammoniacum gum were tested for acetylcholinesterase (AChE) inhibitory activity. The results are presented as percentage inhibition values in Table 1. As clearly shown the table, the hexane and chloroform extracts with 65.2% and 54.9% inhibition exhibited the highest AChE inhibitory activity while dichloromethane extract with 19.4% inhibition at 50 μg/ml concentration exhibited moderate AChE inhibitory activity in agreement with the previous report ²³. However, ethyl acetate and especially methanol extracts did not show significant activity. The IC₅₀ values for AChE inhibition were determined by spectrophotometric measurement of the effect of an increase in the concentrations of test compounds (plant extracts and positive controls) on AChE activity. The IC₅₀ values were then calculated from the dose-effect curves using linear regression. As evident in Table 2, hexane and chloroform extracts exhibited significantly higher AChE activity than dichloromethane and ethyl acetate extracts.

TABLE 1: THE AChE INHIBITORY ACTIVITY OF EXTRACTS (50 μg/ml)

TABLE 2: AChE INHIBITION OF EXTRACTS OF AMMONIACUM GUM AND THE POSITIVE CONTROL GALANTAMINE (N=3)

LC-MS Analysis: The phytochemical profiling of chloroform extract of ammoniacum gum was performed using HPLC-ESI-MS in both positive and negative and PDA analysis. The chromate-grams of LC-MS analysis and HPLC-UV (313 nm) are presented in Fig. 1.

FIG. 1: PHYTOCHEMICAL PROFILING OF A CHCl₃ EXTRACT OF AMMONIACUM GUM PERFORMED USING HPLC-PDA-(±)-ESIMS AND UV (313 nm) DETECTION

FIG. 2: THE CHEMICAL STRUCTURES OF MAJOR COMPOUNDS IN CHCl₃ EXTRACT OF AMMONIACUM GUM WHICH ARE IDENTIFIED BASED ON HPLC-PDA-MS ANALYSIS

TABLE 3: THE CHEMICAL COMPOSITION OF MAJOR COMPOUNDS IDENTIFIED IN CHCl₃ EXTRACT OF AMMONIACUM GUM

Six major compounds were detected based on data obtained from HPLC-PDA-MS. The compounds were identified by comparing with literature data of fragments of compounds and using Scifinder® and Dictionary of Natural Products 26.2 (Chapman and Hall/CRC). The compounds were identified to be doremone A (1), kopetdaghin E (2), dshamirone (3), kopetdaghin D (4), kopetdaghin C (5) and ammodoremine (6) Fig. 2.

Among them, compounds 1, 3, and 6 were reported from the dichloromethane extract of gum-resin of D. ammoniacum ²³. The ESI-MS data and UV-VIS peaks are represented in Table 3. For doremone A (1) the MS spectra are shown in Fig. 3, exploring data showed that m/z 427 corresponding to [M+H]⁺ in positive mode and m/z 425 correspondings to [M-H]- in negative mode, showing a molecular weight of 426

FIG. 3: THE ESI-MS SPECTRUM OF DOREMONE A (1), POSITIVE MODE M/Z 427 [M+H]+ AND M/Z 427 [M-H]-  NEGATIVE MODE

Docking Studies: Acetylcholinesterase and butyrylcholinesterase (BChE) are two cholinesterases known to be responsible for the regulation of cholinergic neurotransmission, whose inhibition causes AD. The function of BChE at cholinergic synapses has not been fully recognized while physiological function of AChE is well known 36, so acetylcholinesterase is known to be the main enzyme for AD and its inhibition can have an important role in occurrence of the disease.

Therefore the experimental and theoretical studies of the ammoniacum gum extracts were evaluated for anti-AD activity by this enzyme. Acetylcholinesterase inhibitory activities of the extracts of ammoniacum gum were investigated using Ellman’s method and the results are shown in Table 1. The major compounds of CHCl₃ extract of ammoniacum gum were identified based on data obtained from HPLC-PDA-MS Table 3 and comparing these data with those published in literature such as SciFinder and dictionary of natural products. The activity of compounds in Dorema gum investigated against the cholinergic enzyme viz. AChE using the molecular docking methods.

The compounds showed good affinity with the enzyme with docking score ranged from -10.89 to -8.62 kcal/mol and Gibbs Free Energy (ΔG) ranged from -49.06 to 90.53 kcal/mol Table 4. The dshamirone (3) and kopetdaghin C (5) were found to possess the highest binding scores with corresponding binding energy values of -10.89 and -10.27 kcal/mol, respectively Table 4 and Fig. 4, where galantamine as positive control showed binding energy of -5.92 kcal/mol. The top-ranked active compound 3 interacted through the formation of two backbone hydrogen bonds with the active site residues (Glh199 and Tyr130 with a hydroxyl group) and showed a hydrophobic interaction between phenol ring and Tyr116, Ile444 and Leu127 Fig. 5.

FIG. 4: DOCKING STUDY OF COMPOUNDS (1-6) IN AChE ASSAY

FIG. 5: THE 3D REPRESENTATION OF INTERACTION BETWEEN THE AChE ENZYME AND DSHAMIRONE (3)

The compound 1 showed an interaction through hydrophobic binding with amino acid residues at the catalytic site (Tyr121, Tyr334, Tyr70, Tyr130, Pro86, Trp279, Phe288, Phe290, Phe330, and Val71) and furthermore a hydrophobic interaction between phenol ring and Tyr116, Tyr84, Tyr121, Phe330, Phe331, and Leu127. The Compound 5 had a hydrophobic interaction with important amino acid residues at the catalytic residues (Trp114, Trp84, Tyr130, Tyr116, and Phe330) and π – π interaction of phenolic group with Hip440 in addition to backbone hydrogen bonding between carbonyl group of kopetdaghin C with Phe288 and Arg289. Compound 2 had two hydrogen-bond interaction between Trp84 with phenyl group and Tyr130 with methoxy group of kopetdaghin E, furthermore to hydrophobic interaction with residues of the protein (Tyr121, Tyr334, Tyr70, Trp279, Phe288, Phe290 and Ile287), hydrophobic interaction between aromatic ring with Tyr116, Ile444, Phe330, Phe331 and Leu127 and π – π interaction of aryl group with Trp84. Compound 4 depicted three hydrogen-bond interactions between Phe330 with carbonyl group, Glh199 with hydroxyl of phenolic group and Tyr130 with methoxy group of kopetdaghin D, in addition to hydrophobic interaction between side-chain substituent with the protein residues (Tyr334, Ile287, Leu282 and Phe290) and hydrophobic interaction between phenol ring and Tyr116, Tyr84, Tyr121, Phe330, Phe331 and Leu127. Compound 6 showed two backbone hydrogen-bond interactions between Tyr121 with carbonyl group and one side-chain hydrogen bond with Phe288, a hydrophobic interaction between side-chain with important amino acid residues at the catalytic residues (Ile287, Tyr334, Phe331, and Phe330) and hydrophobic interaction between aryl ring with Trp279, Leu358, Phe290, and Leu282 Fig. 4.

The results of molecular docking were in good agreement with in-vitro results confirming the inhibitory activity of six major compounds and the overall activity of chloroform extract of ammoniacum gum in inhibition of AChE enzyme.

TABLE 4:  DOCKING SCORES AND H-BOND INTERACTIONS OF THE ACETYLCHOLINESTERASE ACTIVE SITE WITH COMPOUNDS (1-6) AND GALANTAMINE AS POSITIVE CONTROL

According to the results in Table 4, dshamirone (3) exhibited high AChE inhibitory activity, which is probably responsible for the observed activity of the chloroform extract in the present study. The presence of phenolic compounds such as sesquiterpene coumarins/phenols could be associated with the appearance of noticeable antioxidant activity of the chloroform extract following the other reported data for different dorema species ⁴².

CONCLUSION: In conclusion, we have shown that the ammoniacum gum (collected from Shahroud, Iran) extracts exhibited significant acetylcholine esterase inhibitory activity (with the IC₅₀ (μg/ml) of 32.34 and 43.50 for hexane and chloroform extracts, respectively).

Six major compounds from this gum-resin were identified based on HPLC-PDA-MS analysis including doremone A (1), kopetdaghin E (2), dshamirone (3), kopetdaghin D (4), kopetdaghin C (5), and ammodoremine (6). The experimental results were also confirmed by docking analysis. These results may suggest that the ammoniacum gum extracts could be applied for medicinal purposes.

ACKNOWLEDGEMENT: Financial support of this work from the Research Council of the University of Mazandaran is gratefully acknowledged.

CONFLICTS OF INTEREST: Authors declare no conflicts of interest.

REFERENCES:

1. Bekir J, Mars M, Souchard JP and Bouajila J: Assessment of antioxidant, anti-inflammatory, anti-cholinesterase and cytotoxic activities of pomegranate (Punica granatum) leaves. Food and Chemical Toxicology 2013; 55: 470-75.
2. Udayashankar AC, Nandhini M, Rajini SB and Prakash HS: Pharmacological significance of medicinal herb Eclipta alba L - a review. International Journal of Pharmaceutical Sciences and Research 2019; 10: 3592-06.
3. Plazas EA, Avila MC, Delgado WA, Patino OJ and Cuca LE: In-vitro antioxidant and anti-cholinesterase activities of Colombian plants as potential neuroprotective agents. Research Journal of Medicinal Plants 2018; 12: 9-18.
4. Kamal U: Medicinal plants anti-cholinesterase activity and the potential for Alzheimer’s disease treatment. Journal of Diseases and Medicinal Plants 2017; 3: 68-82.
5. Sallam A, Mira A, Ashour A and Shimizu K: Acetylcholine esterase inhibitors and melanin synthesis inhibitors from Salvia officinalis. Phytomedicine 2016; 23: 1005-11.
6. Santos TC, Gomes TM, Pinto BA, Camara AL and Paes AMDA: Naturally occurring acetylcholinesterase inhibitors and their potential use for Alzheimer's disease therapy. Frontiers in Pharmacology 2018; 9: 1-14.
7. Khatami Z, Sarkheil P and Adhami HR: Isolation and characterization of acetylcholinesterase inhibitors from Piper longum Planta Medica 2016; 82: 866.
8. Weller J and Budson A: Current understanding of Alzheimer’s disease diagnosis and treatment. F1000 Research 2018; 7: 1-9.
9. Bhushan I, Kour M, Kour G, Gupta S, Sharma S and Yadav A: Alzheimer’s disease: causes and treatment - a review. Annals of Biotechnology 2018; 1: 1002.
10. Kumar A and Singh A: A review on Alzheimer's disease pathophysiology and its management: an update. Pharmacological Reports 2015; 67: 195-03.
11. Ali-Shtayeh MS, Jamous RM, Zaitoun SY and Qasem IB: In-vitro screening of acetylcholinesterase inhibitory activity of extracts from Palestinian indigenous flora in relation to the treatment of Alzheimer’s disease. Functional Foods in Health and Disease 2014; 4: 381-400.
12. Wang J, Yu JT, Wang HF, Meng XF, Wang C, Tan CC and Tan L: Pharmacological treatment of neuropsychiatric symptoms in Alzheimer's disease: a systematic review and meta-analysis. Journal of Neurology, Neurosurgery, and Psychiatry 2015; 86: 101-09.
13. Mozaffarian V: Umbelliferae. In Flora of Iran. Research Institute of Forests and Rangelands, Tehran 2007.
14. Zandpour F, Vahabi MR, Allafchian AR and Farhang HR: Phytochemical investigation of the essential oils from the leaf and stem of (Apiaceae) in central zagros, Iran. Journal of Herbal Drugs (An International Journal on Medicinal Herbs) 2016; 7: 109-16.
15. Mobeen A, Siddiqui MA, Quamri MA, Itrat M and Imran M: Therapeutic potential of Ushaq (Dorema ammoniacum Don): a unique drug of unani medicine. International Journal of Unani and Integrative Medicine 2018; 2: 11-16.
16. Ghasemi F, Tamadon H, Hosseinmardi N and Janahmadi M: Effects of Dorema ammoniacum gum on neuronal epileptiform activity-induced by pentylenetetrazole. Iranian J of Pharmaceutical Res 2018; 17: 735-42.
17. Zarshenas MM, Arabzadeh A, Tafti MA, Kordafshari G, Zargaran A and Mohagheghzadeh A: Application of herbal exudates in traditional persian medicine. Galen Medical Journal 2013; 1: 78-83.
18. Motevalian M, Mehrzadi S, Ahadi S and Shojaii A: Anti-convulsant activity of Dorema ammoniacum gum: evidence for the involvement of benzodiazepines and opioid receptors. Res in Pharm Sci 2017; 12: 53-59.
19. Pandpazir M, Kiani A, Fakhri S and Mousavi Z: Anti-inflammatory effect and skin toxicity of aqueous extract of Dorema ammoniacum gum in experimental animals. Research Journal of Pharmacognosy 2018; 5: 1-8.
20. Yousefzadi M, Mirjalili MH, Alnajar NA, Zeinali AM and Parsa M: Composition and in-vitro antimicrobial activity of the essential oil of Dorema ammoniacum Don. fruit from Iran. J of Serbian Chem Society 2011; 76: 857-63.
21. Sastry BN: The Wealth of India: Raw Materials, CSIR, Vol. III, New Delhi, 1952.
22. Adhami HR, Farsam H and Krenn L: Screening of medicinal plants from Iranian traditional medicine for acetylcholinesterase inhibition. Phytotherapy Research 2011; 25: 1148-52.
23. Adhami HR, Lutz J, Kählig H, Zehl M and Krenn L: Compounds from gum ammoniacum with acetylcholinesterase inhibitory activity. Scientia Pharmaceutica 2013; 81: 793-06.
24. Rhee IK, van de Meent M, Ingkaninan K and Verpoorte R: Screening for acetylcholinesterase inhibitors from Amaryllidaceae using silica gel thin-layer chromatography in combination with bioactivity staining. Journal of Chromatography A 2001; 915: 217-23.
25. Adhami HR, Linder T, Kaehlig H, Schuster D, Zehl M and Krenn L: Catechol alkenyls from Semecarpus anacardium: acetylcholinesterase inhibition and binding mode predictions. J of Ethnopharmacology 2012; 139: 142-48.
26. Mehta SH, Sudarshi D, Srikrishnan AK, Celentano DD, Vasudevan CK, Anand S, Kumar MS, Latkin C, Solomon S and Solomon SS: Factors associated with injection cessation, relapse and initiation in a community‐based cohort of injection drug users in Chennai, India. Addiction 2012; 107: 349-58.
27. Gauthier S, Emre M, Farlow MR, Bullock R, Grossberg GT and Potkin SG: Strategies for continued successful treatment of Alzheimer's disease: switching cholinesterase inhibitors. Curr Med Res and Opinion 2003; 19: 707-14.
28. Rajmohamed MA, Natarajan S, Palanisamy P, Abdulkader AM and Govindaraju A: Antioxidant and cholinesterase inhibitory activities of ethyl acetate extract of Terminalia chebula: cell-free In-vitro and In-silico Pharmacognosy Magazine 2017; 13: 437.
29. Alzheimer’s A: 2015 Alzheimer's disease facts and figures. Alzheimer's & Dementia: The Journal of the Alzheimer's Association 2015; 11: 332.
30. Rosenberry T, Brazzolotto X, Macdonald I, Wandhammer M, Trovaslet-Leroy M, Darvesh S and Nachon F: Comparison of the binding of reversible inhibitors to human butyrylcholinesterase and acetylcholinesterase: a crystallographic, kinetic and calorimetric study. Molecules 2017; 22: 2098-19.
31. Mladenović M, Arsić B, Stanković N, Mihović N, Ragno R, Regan A, Milićević J, Trtić-Petrović T and Micić R: The targeted pesticides as acetylcholinesterase inhibitors: comprehensive cross-organism molecular modelling studies performed to anticipate the pharmacology of harmfulness to humans in-vitro. Molecules 2018; 23: 2192-29.
32. Chen Y, Lin H, Yang H, Tan R, Bian Y, Fu T, Li W, Wu L, Pei Y and Sun H: Discovery of new acetylcholinesterase and butyrylcholinesterase inhibitors through structure-based virtual screening. RSC Advances 2017; 7: 3429-38.
33. Dighe SN, Deora GS, De la Mora E, Nachon F, Chan S, Parat MO, Brazzolotto X and Ross BP: Discovery and structure–activity relationships of a highly selective butyrylcholinesterase inhibitor by structure-based virtual screening. J of Medicinal Chemistry 2016; 59: 7683-92.
34. Hai-Bang T and Shimizu K: Potent angiotensin-converting enzyme inhibitory tripeptides identified by a computer-based approach. Journal of Molecular Graphics and Modelling 2014; 53: 206-11.
35. Jang C, Yadav DK, Subedi L, Venkatesan R, Venkanna A, Afzal S, Lee E, Yoo J, Ji E, Kim SY and Kim MH: Identification of novel acetylcholinesterase inhibitors designed by pharmacophore-based virtual screening, molecular docking and bioassay. Scientific Reports 2018; 8: 1-21.
36. Mohammadi‐Khanaposhtani M, Mahdavi M, Saeedi M, Sabourian R, Safavi M, Khanavi M, Foroumadi A, Shafiee A and Akbarzadeh T: Design, synthesis, biological evaluation, and docking Study of acetylcholinesterase inhibitors: new acridone‐1, 2, 4‐oxadiazole‐1, 2, 3‐triazole hybrids. Chemical Bio & Drug Design 2015; 86: 1425-32.
37. Arnone A, Nasini G, de Pava OV and Camarda L: Isolation and structure elucidation of doremone, a new spiro-sesquiterpenoidic chroman-2, 4-dione from ammoniac gum resin ChemInform 1992; 23: 248-48.
38. Iranshahi M, Shaki F, Mashlab A, Porzel A and Wessjohann LA: Kopetdaghins a− E, sesquiterpene derivatives from the aerial parts and the roots of Dorema kopetdaghense. Jof Natural Products 2007; 70: 1240-43.
39. Choudhary MI, Baig I, Nur‐e‐Alam M, Shahzad‐ul‐Hussan S, Öndognii P, Bunderya M and Oyun Z: New α‐glucosidase inhibitors from the mongolian medicinal plant Ferula mongolica. Helvetica Chimica Acta 2001; 84: 2409-16.
40. Su BN, Takaishi Y, Honda G, Itoh M, Takeda Y, Kodzhimatov OK and Ashurmetov O: Sesquiterpene phenylpropanoid and sesquiterpene chromone derivatives from Ferula pallida. Journal of Natural Products 2000; 63: 520-22.
41. Appendino G, Nano GM, Viterbo D, De Munno G, Cisero M, Palmisano G and Aragno M: Ammodoremin, an epimeric mixture of prenylated chromandiones from ammoniacum. Helvetica Chimica Acta 1991; 74: 495-500.
42. Wollenweber E, Dörr M and Rustiyan A: Dorema aucheri, the first umbelliferous plant found to produce exudate flavonoids. Phytochemistry 1995; 38: 1417.
    

    ---

    How to cite this article:

    Mazaheritehrani M, Hosseinzadeh R, Mohadjerani M, Tajbakhsh M and Ebrahimi SN: Acetylcholinesterase  inhibitory  activity  of  Dorema ammoniacum  gum  extracts  and  molecular  docking  studies. Int J Pharm Sci & Res 2020; 11(2): 637-44. doi: 10.13040/IJPSR. 0975-8232.11(2).637-44.

    ---

    All © 2013 are reserved by International Journal of Pharmaceutical Sciences and Research. This Journal licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.

    ---