scholarly journals Bioactive Alkaloids from Genus Aspergillus: Mechanistic Interpretation of Their Antimicrobial and Potential SARS-CoV-2 Inhibitory Activity Using Molecular Modelling

2021 ◽  
Vol 22 (4) ◽  
pp. 1866
Author(s):  
Fadia S. Youssef ◽  
Elham Alshammari ◽  
Mohamed L. Ashour

Genus Aspergillus represents a widely spread genus of fungi that is highly popular for possessing potent medicinal potential comprising mainly antimicrobial, cytotoxic and antioxidant properties. They are highly attributed to its richness by alkaloids, terpenes, steroids and polyketons. This review aimed to comprehensively explore the diverse alkaloids isolated and identified from different species of genus Aspergillus that were found to be associated with different marine organisms regarding their chemistry and biology. Around 174 alkaloid metabolites were reported, 66 of which showed important biological activities with respect to the tested biological activities mainly comprising antiviral, antibacterial, antifungal, cytotoxic, antioxidant and antifouling activities. Besides, in silico studies on different microbial proteins comprising DNA-gyrase, topoisomerase IV, dihydrofolate reductase, transcriptional regulator TcaR (protein), and aminoglycoside nucleotidyl transferase were done for sixteen alkaloids that showed anti-infective potential for better mechanistic interpretation of their probable mode of action. The inhibitory potential of compounds vs. Angiotensin-Converting Enzyme 2 (ACE2) as an important therapeutic target combating COVID-19 infection and its complication was also examined using molecular docking. Fumigatoside E showed the best fitting within the active sites of all the examined proteins. Thus, Aspergillus species isolated from marine organisms could afford bioactive entities combating infectious diseases.

Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2351
Author(s):  
Sameh S. Elhady ◽  
Fadia S. Youssef ◽  
Abdulrahman M. Alahdal ◽  
Diena M. Almasri ◽  
Mohamed L. Ashour

Buddleia indica Lam. is an ornamental evergreen shrub with few reports concerning its phytoconstituents and biological activities. Herein, the antihyperglycaemic activity of B. indica leaves methanol extract (BIT) was evaluated for the first time using in vitro and in vivo studies. Molecular modelling was performed for its major phytoconstituents that were further subjected to ADME/TOPAKT (absorption, distribution, metabolism, excretion and toxicity) prediction. BIT revealed considerable reduction in glucose concentration by 9.93% at 50 μg/mL using 3T3-L1 adipocyte culture. It displayed substantial inhibition versus α-glucosidase and α-amylase with IC50 205.2 and 385.06 μg/mL, respectively. In vivo antihyperglycaemic activity of BIT and the ethyl acetate fraction (BIE) was performed using streptozotocin-induced diabetes in rat model. BIT and BIE effectively ameliorate oxidative stress markers in addition to reducing serum blood glucose by 56.08 and 54.00%, respectively, and are associated with a substantial increase in serum insulin by 4.1 and 12.7%, respectively. This can be attributed to its richness with polyphenolic compounds comprising flavonoids, phenolic acids, phenyl propanoids and iridoids. Molecular docking showed that verbascoside and kaempferol displayed the highest fitting within human α-amylase (HA) and human α-glucosidase (HG) active sites, respectively. They showed reasonable pharmacokinetic, pharmacodynamic and toxicity properties, as revealed by ADME/TOPKAT study.


Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3500 ◽  
Author(s):  
Agbo ◽  
Gildenhuys ◽  
Mphahlele

A series of 7-halogeno- (X = F, Cl, Br) and 7-methoxy-substituted acetylated 6-iodo-3-O-flavonol glycosides were prepared, and evaluated for inhibitory effect in vitro against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities. 7-Bromo-2-(4-chlorophenyl)-6-iodo-4H-chromen-4-one-3-O-2,3,4,6-O-tetraacetyl-β-d-glucopyranoside (2k) and 7-bromo-6-iodo-2-(4-methoxyphenyl)-4H-chromen-4-one-3-O-2,3,4,6-O-tetraacetyl-β-d-glucopyranoside (2l) exhibited significant inhibitory effect against AChE activity when compared to the activity of the reference standard, donepezil. Compound 2k was found to be selective against AChE and to exhibit reduced inhibitory effect against BChE activity. 6-Iodo-7-methoxy-2-(4-methoxyphenyl)-4H-chromen-4-one-3-O-2,3,4,6-O-tetraacetyl-β-d-glucopyranoside (2p) was found to exhibit increased activity against BChE, more so than the activity of donepezil. The most active compounds were also evaluated for inhibitory effect against β-secretase activity and for potential radical scavenging activities. The experimental data were complemented with molecular docking (in silico) studies of the most active compounds into the active sites of these enzymes.


2020 ◽  
Vol 16 (4) ◽  
pp. 498-513
Author(s):  
Mohamed E. I. Badawy ◽  
Saad R. El-Zemity

Background: 1,2,4-Triazoles are important five-membered heterocyclic scaffolds due to their extensive biological activities. These products have been an area of growing interest to many researchers around the world as of their diverse biological activities including antifungal and antibacterial activity against broad spectrum of microbial pathogens. Methods: A series of 2-((1H-1,2,4-triazol-1-yl)methyl) derivatives was designed, synthesized and evaluated as antifungal agents against five plant pathogenic fungi (Alternaria tennis, Botryodiplodia theobromae, Fusarium moniliforme, Fusarium oxysporum and Helminthosporium turcicum) to meet the urgent need of new antifungal agents with improved activity and broader spectrum. In silico studies including pharmacophore modeling, virtual screening, drug-likeness analysis and ADMET prediction were examined. In addition, the elucidation of the activity is based on the molecular docking to the active site of the Sterol 14α-Demethylase Cytochrome P450 (CYP51) was investigated. Results: The results of antifungal activity indicated that the compounds containing tert or sec-butyl as hydrophobic substituents on a phenyl ring significantly increased the activity (compounds 4, 5 and 6) with EC50 in the range of 8-84 mg/L of all tested fungi. The pharmacophore modeling produced an accurate projecting model (Hypo 1) from these derivatives. The superlative Hypo1 consists of three features counting two hydrogen bond acceptors (HBA) and one hydrophobic (HYD). The docking results showed approximately a similar binding degree at the active sites of the fungal enzyme (CYP51) as a standard fungicide penconazole. Conclusion: According to data obtained, some derivatives, especially those with tert or sec-butyl substituents on the phenyl ring, were more potent against phytopathogenic fungi. These compounds (e.g., 4, 5, and 6) should develop into new potential fungicides as a desirable activity.


2021 ◽  
Vol 12 ◽  
Author(s):  
Fadia S. Youssef ◽  
Ahmed E. Altyar ◽  
Abdelsattar M. Omar ◽  
Mohamed L. Ashour

Phytochemical investigation of Buddleja indica Lam. leaves methanol extract (BIT) resulted in the isolation of six known compounds for the first time from the plant, namely, p-hydroxybenzoic acid 1), caffeic acid 2), quercetin 3-O-β-D glucoside-7-O-α-L-rhamnoside 3), kaempferol 3-O-β-D glucoside-7-O-α-L-rhamnoside 4), quercetin 7-O-β-D glucoside 5) and kaempferol 6). BIT extract showed potent antibacterial activity with MIC values ranging between 0.48 and 1.95 μg/ml with Bacillus subtilis was the most susceptible to the BIT effect. It showed a notable antimycobacterial and anti-Helicobacter pylori activity with MIC values of 100 and 80 μg/ml, respectively. Vesicular stomatitis virus (VSV) was more sensitive to the antiviral activity of BIT comparable to herpes simplex virus type 1 (HSV-1), showing 48.38 and 41.85% inhibition of the viral replication at a dose of 50 μg/ml for VSV and HSV-1, respectively. In silico molecular docking of the isolated compounds revealed that caffeic acid 2) showed the highest fitting within the active sites of DNA-gyrase, topoisomerase IV, and SARS-CoV-2 MPro. Quercetin 7-O-β-D glucoside 5) revealed the best fitting in dihydrofolate reductase active site with ∆ G value equals −36.53 Kcal/mol. Kaempferol 6) exhibited the highest fitting towards β-lactamase, SARS-CoV-2PLpro, and SARS-CoV-2 3CLpro active sites. Thus, B. indica Lam. can be considered as a future source of cheap, substantially safe, and credible antibacterial, antifungal, and antiviral candidate of natural origin that could effectively participate in solving the problem of COVID-19 pandemic. These findings provide a scientific consolidation for the ethnomedicinal uses of Buddleja indica Lam. as a topical antiseptic.


Author(s):  
Junjian Li ◽  
Lianbao Ye ◽  
Yuanyuan Wang ◽  
Ying Liu ◽  
Xiaobao Jin ◽  
...  

Background: Spirocyclic indoline compounds widely exist in numerous natural products with good biological activities and some drug molecules in many aspects. In recent years, it has attracted extensive attention as potent anti-tumor agents in the fields of pharmacology and chemistry. Objective: In this study, we focused on designing and synthesizing a set of novel 1'-H-spiro[indole-3,4'-piperidine] derivatives, which were evaluated by preliminary bioactivity experiment in vitro and molecular docking. Method: The key intermediate 1'-methylspiro[indoline-3,4'-piperidine] (B4) reacted with benzenesulfonyl chloride with different substituents under alkaline condition to obtain its sulfonyl derivatives (B5-B10). We evaluated their antiproliferative activities against A549, BEL-7402 and HeLa cells by MTT assay. We performed the CDOCKER module in Discovery Studio 2.5.5 software for molecular modeling of compound B5, and investigated the binding of compound B5 with the target proteins from PDB database. Results: The results indicated that compounds B4-B10 exhibited good antiproliferative activities against the above three types of cells, in which compound B5 with chloride atom as electron-withdrawing substituent on a phenyl ring showed the highest potency against BEL-7402 cells (IC50=30.03±0.43 μg/mL). By binging of the prominent bioactive compound B5 to CDK, c-Met, EGFR protein crystals, The binding energy of B5 with these three types receptors are -44.3583 kcal/mol, - 38.3292 kcal/mol, -33.3653 kcal/mol respectively. Conclusion: Six 1'-methylspiro[indoline-3,4'-piperidine] derivatives were synthesized and evaluated against BEL-7402, A- 549, HeLa cell lines. Compound B5 showed significant inhibition on BEL-7402 cell lines. Molecular docking revealed that B5 showed good affinity by the good fitting between B5 and these three targets with amino acid residues in active sites which encourage us to conduct further evaluation such as the kinase experiment.


2020 ◽  
Vol 16 ◽  
Author(s):  
Mahboob Ali ◽  
Momin Khan ◽  
Khair Zaman ◽  
Abdul Wadood ◽  
Maryam Iqbal ◽  
...  

: Background: The inhibition of α-amylase enzyme is one of the best therapeutic approach for the management of type II diabetes mellitus. Chalcone possesses a wide range of biological activities. Objective: In the current study chalcone derivatives (1-17) were synthesized and evaluated their inhibitory potential against α-amylase enzyme. Method: For that purpose, a library of substituted (E)-1-(naphthalene-2-yl)-3-phenylprop-2-en-1-ones was synthesized by ClaisenSchmidt condensation reaction of 2-acetonaphthanone and substituted aryl benzaldehyde in the presence of base and characterized via different spectroscopic techniques such as EI-MS, HREI-MS, 1H-, and 13C-NMR. Results: Sixteen synthetic chalcones were evaluated for in vitro porcine pancreatic α-amylase inhibition. All the chalcones demonstrated good inhibitory activities in the range of IC50 = 1.25 ± 1.05 to 2.40 ± 0.09 μM as compared to the standard commercial drug acarbose (IC50 = 1.34 ± 0.3 μM). Conclusion: Chalcone derivatives (1-17) were synthesized, characterized, and evaluated for their α-amylase inhibition. SAR revealed that electron donating groups in the phenyl ring have more influence on enzyme inhibition. However, to insight the participation of different substituents in the chalcones on the binding interactions with the α-amylase enzyme, in silico (computer simulation) molecular modeling analyses were carried out.


2019 ◽  
Vol 16 (6) ◽  
pp. 696-710
Author(s):  
Mahmoud Balbaa ◽  
Doaa Awad ◽  
Ahmad Abd Elaal ◽  
Shimaa Mahsoub ◽  
Mayssaa Moharram ◽  
...  

Background: ,2,3-Triazoles and imidazoles are important five-membered heterocyclic scaffolds due to their extensive biological activities. These products have been an area of growing interest to many researchers around the world because of their enormous pharmaceutical scope. Methods: The in vivo and in vitro enzyme inhibition of some thioglycosides encompassing 1,2,4- triazole N1, N2, and N3 and/or imidazole moieties N4, N5, and N6. The effect on the antioxidant enzymes (superoxide dismutase, glutathione S-transferase, glutathione peroxidase and catalase) was investigated as well as their effect on α-glucosidase and β-glucuronidase. Molecular docking studies were carried out to investigate the mode of the binding interaction of the compounds with α- glucosidase and β -glucuronidase. In addition, quantitative structure-activity relationship (QSAR) investigation was applied to find out the correlation between toxicity and physicochemical properties. Results: The decrease of the antioxidant status was revealed by the in vivo effect of the tested compounds. Furthermore, the in vivo and in vitro inhibitory effects of the tested compounds were clearly pronounced on α-glucosidase, but not β-glucuronidase. The IC50 and Ki values revealed that the thioglycoside - based 1,2,4-triazole N3 possesses a high inhibitory action. In addition, the in vitro studies demonstrated that the whole tested 1,2,4-triazole are potent inhibitors with a Ki magnitude of 10-6 and exhibited a competitive type inhibition. On the other hand, the thioglycosides - based imidazole ring showed an antioxidant activity and exerted a slight in vivo stimulation of α-glucosidase and β- glucuronidase. Molecular docking proved that the compounds exhibited binding affinity with the active sites of α -glucosidase and β-glucuronidase (docking score ranged from -2.320 to -4.370 kcal/mol). Furthermore, QSAR study revealed that the HBD and RB were found to have an overall significant correlation with the toxicity. Conclusion: These data suggest that the inhibition of α-glucosidase is accompanied by an oxidative stress action.


Author(s):  
Dnyaneshwar Baswar ◽  
Abha Sharma ◽  
Awanish Mishra

Background: Alzheimer’s disease (AD), an irreversible complex neurodegenerative disorder, is most common type of dementia, with progressive loss of cholinergic neurons. Based on the multi- factorial etiology of Alzheimer’s disease, novel ligands strategy appears as up-coming approach for the development of newer molecules against AD. This study is envisaged to investigate anti-Alzheimer’s potential of 10 synthesized compounds. The screening of compounds (1-10) was carried out using in silico techniques. Methods: For in silico screening of physicochemical properties of compounds molinspiration property engine v.2018.03, Swiss ADME online web-server and pkCSM ADME were used. For pharmacodynamic prediction PASS software while toxicity profile of compounds were analyzed through ProTox-II online software. Simultaneously, molecular docking analysis was performed on mouse AChE enzyme (PDB ID:2JGE, obtained from RSCB PDB) using Auto Dock Tools 1.5.6. Results: Based on in silico studies, compound 9 and 10 have been found to have better drug likeness, LD50 value, and better anti-Alzheimer’s, nootropic activities. However, these compounds had poor blood brain barrier (BBB) permeability. Compound 4 and 9 were predicted with better docking score for AChE enzyme. Conclusion: The outcome of in silico studies have suggested, out of various substitutions at different positions of pyridoxine-carbamate, compound 9 have shown promising drug likeness, with better safety and efficacy profile for anti-Alzheimer’s activity. However, BBB permeability appears as one the major limitation of all these compounds. Further studies are required to confirm its biological activities.


Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 330
Author(s):  
Timofey V. Malyarenko ◽  
Alla A. Kicha ◽  
Valentin A. Stonik ◽  
Natalia V. Ivanchina

Sphingolipids are complex lipids widespread in nature as structural components of biomembranes. Commonly, the sphingolipids of marine organisms differ from those of terrestrial animals and plants. The gangliosides are the most complex sphingolipids characteristic of vertebrates that have been found in only the Echinodermata (echinoderms) phylum of invertebrates. Sphingolipids of the representatives of the Asteroidea and Holothuroidea classes are the most studied among all echinoderms. In this review, we have summarized the data on sphingolipids of these two classes of marine invertebrates over the past two decades. Recently established structures, properties, and peculiarities of biogenesis of ceramides, cerebrosides, and gangliosides from starfishes and holothurians are discussed. The purpose of this review is to provide the most complete information on the chemical structures, structural features, and biological activities of sphingolipids of the Asteroidea and Holothuroidea classes.


Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 751
Author(s):  
Marwa Reda Bakkar ◽  
Ahmed Hassan Ibrahim Faraag ◽  
Elham R. S. Soliman ◽  
Manar S. Fouda ◽  
Amir Mahfouz Mokhtar Sarguos ◽  
...  

COVID-19 is a pandemic disease caused by the SARS-CoV-2, which continues to cause global health and economic problems since emerging in China in late 2019. Until now, there are no standard antiviral treatments. Thus, several strategies were adopted to minimize virus transmission, such as social distancing, face covering protection and hand hygiene. Rhamnolipids are glycolipids produced formally by Pseudomonas aeruginosa and as biosurfactants, they were shown to have broad antimicrobial activity. In this study, we investigated the antimicrobial activity of rhamnolipids against selected multidrug resistant bacteria and SARS-CoV-2. Rhamnolipids were produced by growing Pseudomonas aeruginosa strain LeS3 in a new medium formulated from chicken carcass soup. The isolated rhamnolipids were characterized for their molecular composition, formulated into nano-micelles, and the antibacterial activity of the nano-micelles was demonstrated in vitro against both Gram-negative and Gram-positive drug resistant bacteria. In silico studies docking rhamnolipids to structural and non-structural proteins of SARS-CoV-2 was also performed. We demonstrated the efficient and specific interaction of rhamnolipids with the active sites of these proteins. Additionally, the computational studies suggested that rhamnolipids have membrane permeability activity. Thus, the obtained results indicate that SARS-CoV-2 could be another target of rhamnolipids and could find utility in the fight against COVID-19, a future perspective to be considered.


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