Synthesis, Bioactivities and In-silico Docking Studies of Azaleatin-A Quercetin Partial Methyl Ether: SAR Study

2019 ◽  
Vol 15 (1) ◽  
pp. 103-108 ◽  
Author(s):  
Nanjan Pandurangan ◽  
Chinchu Bose ◽  
Sreejith Meppoyilam ◽  
Veni C. Kalathil ◽  
Anjana Murali ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Dimethyl Ether ◽  
Methyl Ether ◽  
In Silico ◽  
Chemical Space ◽  
Radical Scavenging ◽  
In Vivo Studies ◽  
Scavenging Activity ◽  
In Silico Docking ◽  
Modelling Studies

Background: During last two decades, good progress has been made for the flavonoids in metabolic and infectious diseases. However, expectations have not been fulfilled when these compounds were extended to the in vivo studies, particularly in humans. This could due to low bioavailability and less absorption of flavonoids in the biological systems. A recent study revealed that methylation of flavonoids can bring about dramatic changes in pharmacokinetic and biochemical properties. Often, the partially methylated flavonoids show better activities by improving their metabolic stability, membrane transport capacity, facilitating absorption and for oral bio-availability. Though, partial methyl ethers occupy a large chemical space, their biological properties has not been well established. Azaleatin (quercetin-5-O-methyl ether) is one of such group of naturally occurring molecules. Methods: In the present study, we have utilized methoxymethyl (MOM) protecting groups for the preparation of azaleatin. Synthesized compounds and their derivatives were subjected for α-Amylase and DPPH activities. α-Amylase activity can be measured in vitro by hydrolysis of starch in presence of α-amylase enzyme. Antioxidant capacity was evaluated by measuring the scavenging activity of azaleatin and related compounds on the 2,2- diphenyl-l-1-picrylhydrazil (DPPH) radical. In order to identify the binding mode of the compound azaleatin, Auto Dock Tools (http://mgltools.scripps.edu) were used. Results: Quercetin, along with their derivatives, monomethyl ethers i.e. azaleatin, isorhamnetin, tamarixetin; dimethyl ether i.e. quercetin-3,7-dimethyl ether; quercetin-3,3',7-trimethyletherpachypodol; quercetin-3,3',4'7-tetramethyl ether and quercetin pentamethyl ether were taken for α- amylase inhibitory activity. The study showed that azaleatin was found to be comparable with the standard for the inhibition of α-amylase amongst the tested compounds. Since, azaleatin is a best for the inhibition of α-amylase, this compound was taken for the in-silico molecular modelling studies. Azaleatin, showed a good docking energy (-8.8 Kcalmol-1) with the α-amylase receptor. Similarly, other closely related derivatives were studied for their antioxidant capacity. It was found that amongst the compound tested quercetin was found to be best (EC50 of 30µg/mL) for their antioxidant capacity and second best compound was azaleatin; which showed EC50 of 36.1µg/mL. Conclusion: An efficient synthesis of azaleatin, a lesser known flavone has been achieved from quercetin. Amongst the compounds tested, azaleatin was found to inhibit α-amylase with the acceptable radical scavenging activity. Further, in-silico modelling studies indicated that azaleatin found to have very good affinity with the key residues i.e. Gln63, Asp197 and Arg195 of α-amylase receptor. Since, azaleatin has other free hydroxyls in their template, it can be effectively utilized for the activity improvement through further structural modifications.

α-Glucosidase Inhibition, Antioxidant and Docking Studies of Hydroxycoumarins and their Mono and Bis O-alkylated/acetylated Analogs

2018 ◽  
Vol 15 (2) ◽  
pp. 127-135 ◽  
Author(s):  
Parvesh Singh ◽  
Nomandla Ngcoya ◽  
Ramgopal Mopuri ◽  
Nagaraju Kerru ◽  
Neha Manhas ◽  
...  
Keyword(s):  
In Silico ◽  
Biological Activities ◽  
Wide Spectrum ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Catalytic Site ◽  
Docking Simulations ◽  
In Silico Docking ◽  
Anti Oxidant

Background: Diabetes Mellitus (DM) is a complex metabolic disease illustrated by abnormally high levels of plasma glucose or hyperglycaemia. Accordingly, several α-glucosidase inhibitors have been developed for the treatment of diabetes and other degenerative disorders. While, a coumarin ring has the privilege to represent numerous natural and synthetic compounds with a wide spectrum of biological activities e.g. anti-cancer, anti-HIV, anti-viral, anti-malarial, anti-microbial, anti-convulsant, anti-hypertensive properties. Besides this, coumarins have also shown potential to inhibit α-glucosidase leading to a generation of new promising antidiabetic agents. However, the testing of O-substituted coumarins for α-glucosidase inhibition has evaded the attention of medicinal chemists. Methods: For O-alkylation/acetylation reactions, the hydroxyl coumarins (A-B) initially activated by K2CO3 in dry DMF were reacted with variedly substituted haloalkanes at room temperature under nitrogen. The synthesized compounds were tested for their α-glucosidase (from Saccharomyces cerevisiae) inhibitory activity and anti-oxidant activity using DPPH radical scavenging activity. In silico docking simulations were conducted using CDocker module in DS (Accelrys) to explore the binding modes of the representative compounds in the catalytic site of α-glucosidase. Results: All the coumarin analogues (A1, B1, A2-A10, B2-B8) including their precursors (A-B) were evaluated for their in vitro α-glucosidase inhibition using acarbose as a standard inhibitor. All the mono O-alkylated coumarins (except A1) showed significant (p <0.05) α-glucosidase inhibition relative to the hydroxyl coumarin (A) with IC50 values ranging between 11.084±0.117 to 145.24± 29.22 µg/mL. Compound 7-(benzyloxy)-4, 5-dimethyl-2H-chromen-2-one (A9) bearing a benzyl group (Ph-CH2-) at position 7 showed a remarkable (p <0.05) increase in the activity (IC50 = 11.084±0.117 µg/mL), almost four-fold more than acarbose (IC50 = 40.578±5.999 µg/mL). The introduction of –NO2 group dramatically improved the anti-oxidant activity of coumarin, while the O-alkylation/acetylation decreased the activity. Conclusion: The present study describes the synthesis of functionalized coumarins and their evaluation for α-glucosidase inhibition and antioxidant activity under in vitro conditions. Based on IC50 data, the mono O-alkylated coumarins were observed to be stronger inhibitors of α-glucosidase with respect to their bis O-alkylated analogues. Coumarin (A9) bearing O-benzyloxy group displayed the strongest α-glucosidase inhibition, even higher than the standard inhibitor acarbose. The coumarin (A10) bearing –NO2 group showed the highest anti-oxidant activity amongst the synthesized compounds, almost comparable to the ascorbic acid. Finally, in silico docking simulations revealed the role of hydrogen bonding and hydrophobic forces in locking the compounds in catalytic site of α-glucosidase.

scholarly journals OPTIMASI KAPASITAS ANTIOKSIDAN KECAMBAH KEDELAI VARIETAS WILIS

2021 ◽  
Vol 1 (2) ◽  
pp. 65-74
Author(s):  
Wenny Sinaga
Keyword(s):  
Antioxidant Capacity ◽  
Dimethyl Ether ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Acid Methyl Ester ◽  
Antioxidant Compounds ◽  
Hexadecanoic Acid ◽  
Acid Methyl ◽  
Germination Process ◽  
Water Ratio

Kedelai adalah produk pangan bernilai gizi tinggi yang banyak dikonsumsi oleh masyarakat Indonesia. Pada penelitian ini, kedelai dimodifikasi dengan cara perkecambahan. Komponen zat gizi akan berubah menjadi senyawa-senyawa yang lebih sederhana selama proses perkecambahan sehingga menjadi lebih mudah dicerna bagi tubuh manusia. Selain itu, perkecambahan juga dapat meningkatkan kapasitas antioksidan. Tujuan dari penelitian ini adalah menentukan kondisi perkecambahan untuk mengoptimalkan kapasitas antioksidan dari biji kedelai varietas Wilis. Hasil penelitian menunjukkan bahwa kondisi terbaik untuk mengoptimalkan kapasitas antioksidan adalah dengan cara perkecambahan pada suhu 25°C selama 15 jam dengan rasio biji kedelai dan air 1:3 tanpa adanya penambahan garam. Kapasitas antioksidan kecambah kedelai var. Wilis pada 100 ppm memiliki radical scavenging activity sebesar 9,69% dengan scavenging ternormalisasi 0,65% dengan total fenol 2,1 mg GAE/g pada biji dan 2,9 mg GAE/g pada kecambah. Dari hasil identifikasi GC-MS ditemukan senyawa-senyawa antioksidan yang terdapat pada biji kedelai dan kecambah kedelai berupa benzoic acid, 2-methoxy-4-vinylphenol, 2,5-dihydroxytoluene, pyrogallol 1,3-dimethyl ether, 2,5-dihydroxytoluene, pyrogallol 1,3-dimethyl ether, hexadecanoic acid methyl ester dan methyl oleate serta terdapat juga senyawa-senyawa antioksidan baru yang muncul setelah proses perkecambahan yaitu neophytadiene, campesterol, stigmasterol, delta-tocopherol dan gamma-tocopherol.  ABSTRACT: Soybean is a high nutrition food product that is largely consumed by Indonesians. In this research, the soybean will be modified by going through the germination process. Complex nutrition would be changed into substances that were more simple during the germination process. Therefore, it would be easier for human to digest it. Moreover, this process might also increase the antioxidant capacity of the soybean itself. The aim of this research is to find out the most suitable germination condition in order to acquire the optimum antioxidant capacity of Wilis variety soybean. The result shows that the best condition to optimize the antioxidant capacity is by performing the germination process at 25°C for 15 hours with soybean to water ratio being 1:3 without any salt addition. The antioxidant capacity of Wilis soybean at 100 ppm has 9,69% of radical scavenging activity, with 0,65% being normalized. The total phenolic compound found in the beans was 2,1 mg GAE/g, whereas 2,9 mg GAE/g were found in the sprout. Based on the GC-MS identification, the antioxidant compounds that are found in both the soybean and sprout are known to be benzoic acid, 2-methoxy-4-vinylphenol, 2,5-dihydroxytoluene, pyrogallol 1,3-dimethyl ether, 2,5-dihydroxytoluene, pyrogallol 1,3-dimethyl ether, hexadecanoic acid methyl ester, and methyl oleate. In addition, there are also several new antioxidant compounds that emerge after the germination process, which are neophytadiene, campesterol, stigmasterol, delta-tocopherol, and gamma-tocopherol. Keywords: Soybean var. Wilis, Sprout, Antioxidant, Water Ratio

scholarly journals 2,4-Furfurylidene-D-sorbitol and its tetra-methyl ether: synthesis, conformational studies, and radical scavenging activity

ARKIVOC ◽  
2016 ◽  
Vol 2016 (5) ◽  
pp. 50-68 ◽  
Author(s):  
Pierangela Ciuffreda ◽  
Andrea Brizzolari ◽  
Silvana Casati ◽  
Ivano Eberini ◽  
Luca Palazzolo ◽  
...  
Keyword(s):  
Methyl Ether ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Scavenging Activity ◽  
Conformational Studies ◽  
Ether Synthesis

In Vitro Synthesis, Structure elucidation and its antioxidant properties of Platinum(IV)-hydrazide complexes: Molecular modeling of free-hydrazides suggested as potent lipoxygenase inhibitor

2021 ◽  
Vol 17 ◽  
Author(s):  
Rooma Badar ◽  
Uzma Ashiq ◽  
Rifat Ara Jamal ◽  
Parveen Akhter ◽  
Mohammad Mahroof-Tahir ◽  
...  
Keyword(s):  
Enzyme Inhibition ◽  
In Silico ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Biologically Active ◽  
Central Metal ◽  
In Vitro Synthesis ◽  
In Silico Docking ◽  
In Silico Studies ◽  
Nitric Oxide Radical

Background: Combination of biologically active ligand and metal in one molecule may increase the activity and reduce the toxicity. Objectives: In this study synthesis and characterization of platinum(IV) complexes with bioactive hydrazide ligands is discussed. Method: Elemental analysis, conductivity measurements and spectroscopic studies were used to elucidate the structure of complexes. Results: Our study suggests that hydrazide ligands coordinate with Pt(IV) in bidenate fashion. The platinum(IV) complexes have octahedral geometry with metal to ligand ratio of 1:2. Hydrazide ligands coordinated with central metal platinum(IV) by oxygen of carbonyl group and nitrogen of primary amine. Synthesized complexes exhibited variable DPPH radical scavenging and lipoxygenase inhibition activity. Furthermore, it is also found that Pt(IV)-hydrazide complexes are more potent superoxide and nitric oxide radical scavengers than their uncoordinated hydrazide ligands while in case of lipoxygenase enzyme inhibition, some of the free hydrazide ligands are more active than their respective Pt(IV) complexes. In silico docking technique explores molecular interactions of synthesized ligands in the active site of lipoxygenase enzyme. Predicted docking energies are in good agreement with experimental data suggesting that in silico studies might be useful for discovery of therapeutic candidates. Conclusion: Structure function relationship demonstrates that the radical scavenging and enzyme inhibition activities of the Pt(IV) compounds are effected by nature of ligand, position of substituent, electronic and steric effects. However, electronic factor seem to play more important role than other factors.

scholarly journals Concentrating rosmarinic acid from Orthosiphon aristatus extract for high antioxidative candies

2021 ◽  
Vol 45 (1) ◽  
pp. 118-128
Author(s):  
Jin Ru Lim ◽  
Lee Suan Chua
Keyword(s):  
Health Promotion ◽  
Antioxidant Capacity ◽  
Rosmarinic Acid ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Scavenging Activity ◽  
Herbal Ingredient ◽  
Beneficial Property ◽  
Chromatographic Profiles ◽  
Good Agreement

Extraction and fractionation were carried out to concentrate the rosmarinic acid from Orthosiphon aristatus in order to increase the value of herbal candy formulated using polyphenolic rich extract. The herb was extracted and fractionated in column chromatography, and then analyzed by LC-MS/MS. The collected plant fractions with similar chromatographic profiles were combined and determined for antioxidant capacities expressed in radical scavenging activity. The results showed that the antioxidant capacity was in good agreement with the concentration of rosmarinic acid in the combined fractions. The combined fraction II showed the highest rosmarinic acid content, 3.8%w/w and the highest antioxidant capacity (IC50=14.922 ppm). The incorporation of rosmarinic acid rich extract into candy formulation did not statistically affect the antioxidant capacity. Hence, the rosmarinic acid rich extract could be another choice of ingredient to enhance the beneficial property of candies. Candy is another form of carrier to deliver herbal ingredient for health promotion.

scholarly journals Flavonoids and Triterpenoids from the Roots of Rosa laevigata

2017 ◽  
Vol 58 (4) ◽  
Author(s):  
Ning Li ◽  
Kaijin Wang ◽  
Shiping Li ◽  
Xiangyu Zhai ◽  
Tianming Wang ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Methyl Ether ◽  
Betulinic Acid ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Scavenging Activity ◽  
Dpph Assay ◽  
Isolation And Identification ◽  
Phytochemical Investigation ◽  
Rosa Laevigata

<p>Phytochemical investigation on the root of <em>R. laevigata</em> led the isolation and identification of two new flavonoids, (+)-catechin-8-acetic acid (<strong>1</strong>) and guibourtacacidine 4-methyl ether (<strong>2</strong>), one known flavonoid, guibourtacacidine (<strong>3</strong>), along with seven known triterpenoids, euscaphic acid (<strong>4</strong>), kajiichigoside F1 (<strong>5</strong>), nigaichigoside F2 (<strong>6</strong>), rubuside J (<strong>7</strong>), tomentic acid (<strong>8</strong>), rosamutin (<strong>9</strong>) and betulinic acid (<strong>10</strong>). Their structures were established on the basis of spectroscopic evidence and comparisons with literature data. Compounds <strong>1</strong>, <strong>2</strong> and <strong>3</strong> showed considerable radical scavenging activity in the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay.<strong></strong></p>

scholarly journals Evaluation of Bioactive Metabolites and Antioxidant-Rich Extracts of Amaranths with Possible Role in Pancreatic Lipase Interaction: In-Silico and In-Vitro Studies

Metabolites ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 676
Author(s):  
Swati Chaturvedi ◽  
Promila Gupta
Keyword(s):  
Pancreatic Lipase ◽  
In Silico ◽  
Daily Intake ◽  
Radical Scavenging ◽  
Pancreatic Injury ◽  
Bioactive Metabolites ◽  
In Silico Docking ◽  
Trolox Equivalent ◽  
Functional Components

Fat/carbohydrate-rich diet consumption or elevated secretion of pancreatic lipase (PL) in pancreatic injury results in increased fat digestion and storage. Several metabolites in plant-based diets can help achieve the requirements of nutrition and fitness together. Presently, nutritional metabolites from Amaranthus tricolor, A. viridis, and Achyranthes aspera were assessed and predicted for daily intake. The volatile-metabolite profiling of their extracts using GC-MS revealed various antioxidant and bioactive components. The implication of these specialized components and antioxidant-rich extracts (EC50 free radical scavenging: 34.1 ± 1.5 to 166.3 ± 14.2 µg/mL; FRAP values: 12.1 ± 1.0 to 34.0 ± 2.0 µg Trolox Equivalent/mg) in lipolysis regulation by means of interaction with PL was checked by in-silico docking (Betahistine and vitamins: ΔGbind −2.3 to −4.4 kcal/mol) and in-vitro fluorescence quenching. Out of the various compounds and extracts tested, Betahistine, ATRA and AVLA showed better quenching the PL fluorescence. The identification of potential extracts as source of functional components contributing to nutrition and fat regulation can be improved through such study.

scholarly journals Influence of Cooking Methods on Antioxidant Activities of Selected Leafy Vegetables Gymnema lactiferum, Wattakaka volubilis, and Argyreia populifolia in Sri Lanka

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Sathsara T. Deyalage ◽  
Indira Wickramasinghe ◽  
Nimesha Amarasinghe ◽  
Gayan Thilakarathna
Keyword(s):  
Antioxidant Capacity ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Leafy Vegetables ◽  
Total Phenolic ◽  
Thermal Treatments ◽  
Scavenging Activity ◽  
Antioxidant Power ◽  
Green Leafy Vegetables ◽  
Ferric Reducing Antioxidant Power

Green leafy vegetables (GLVs) are abundant in bioactive compounds and constitute a crucial part of a balanced diet. Sri Lankan green leafy vegetables which are edible and available for consumption have not been thoroughly investigated, whilst their consumption can deflate the risk of arising several degenerative diseases, such as cancer and cardiovascular diseases. The present study was aimed at evaluating the antioxidant capacities of the leafy vegetables, Gymnema lactiferum (Kurignan), Wattakaka volubilis (Aguna), and Argyreia populifolia (Girithilla), with different thermal treatments (70°C, 120°C, and 170°C) which are used in domestic cooking processes. Heat treatments significantly affect the antioxidant capacity and polyphenolic content of most vegetables analyzed, either increasing or decreasing the concentration of these compounds. In the presence of thermal treatments, Gymnema lactiferum (14.52-20.28 mg GAE/g DW) and Wattakaka volubilis (19.75-27.13 mg GAE/g DW) showed a significantly higher ( p < 0.05 ) total phenolic content. The temperature treatment did not alter the ABTS radical scavenging activity in Gymnema lactiferum. In contrast, an increment of ferric reducing antioxidant power (41.26-54.85 mg TE/g DW) and DPPH radical scavenging activity (0.11-0.26 mg TE/g DW) was observed. Wattakaka volubilis treated at 170°C appeared to have a significantly higher amount ( 104.93 ± 1.41   mg TE/g DW) of ferric reducing antioxidant power compared to its raw form. All cooking processes with their corresponding thermal treatments caused a significantly lower ( p < 0 ) amount of antioxidant capacity in Argyreia populifolia.

scholarly journals Antioxidant Capacities of Jujube Fruit Seeds and Peel Pulp

2020 ◽  
Vol 10 (17) ◽  
pp. 6007 ◽  
Author(s):  
Yung-Sheng Lin ◽  
Wen-Shin Lin ◽  
Jing-Wen Tung ◽  
Ya-Chih Cheng ◽  
Min-Yun Chang ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Radical Scavenging Activity ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Reducing Power ◽  
Dry Weight ◽  
Total Phenolic ◽  
Scavenging Activity ◽  
Jujube Fruit

In this study, the effects of different fruit parts and extraction conditions on the antioxidant properties of jujube (Ziziphus jujuba Mill.) fruit were investigated. Five in vitro antioxidant models and statistical analyses were performed. The results revealed that jujube peel with pulp (peel pulp) exhibited better antioxidant capacity than did seeds. Overall, jujube peel pulp extracted using 50% ethanol at 60 °C exhibited the best antioxidant capacity in terms of 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (0.3 ± 0 mg/mL), 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity (0.5 ± 0 mg/mL), total phenolic content (38.3 ± 0.4 mg gallic acid equivalent per gram dry weight), total flavonoid content (43.8 ± 0.2 mg quercetin equivalent per gram dry weight), and reducing power (41.9 ± 2.2 mg ascorbic acid equivalent per gram dry weight). The results indicated that jujube peel pulp is a more potential natural antioxidant than seeds.

scholarly journals Comparative study of in vitro, ex vitro and in vivo grown plants of Arnica montana – polyphenols and free radical scavenging activity

2013 ◽  
Vol 72 (1) ◽  
pp. 13-22 ◽  
Author(s):  
Milena Nikolova ◽  
Mariya Petrova ◽  
Ely Zayova
Keyword(s):  
Free Radical ◽  
Methyl Ether ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Scavenging Activity ◽  
Ex Vitro ◽  
Polyphenolic Content

Abstract Arnica montana L. is an endangered species rich in sesquiterpene lactones, phenolic acids and flavonoids with high pharmaceutical value. The polyphenolic content and free radical scavenging activity of plants that had passed all stages of cultivation: micropropagation and rooting (in vitro), adaptation in greenhouse (ex vitro) and mountain conditions (in vivo) were evaluated. Four surface flavonoid aglycones [scutellarein 6-methyl ether (hispidulin), scutellarein 6,4’-dimethyl ether (pectolinarigenin), 6-OH luteolin 6-methyl ether and kempferol-6-methyl ether] were detected in the acetone exudates of the studied samples bymeans of thin layer chromatography.No differences in the accumulation of surface flavonoids were found among the tested leaf extracts of in vitro, ex vitro and in vivo samples. However, the extracts from the flowers were richer in surface flavonoids than extracts from the leaves. The methanol extracts of the samples from ex vitro and in vivo grown A. montana plants had significantly higher radical scavenging activity and polyphenolic content than the extracts of in vitro samples. The observed differences in the contents of these biologically active compounds were related to different growth conditions and stages of plant development. The biotechnological method of A. montana established holds promise for the future production of antioxidants.

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