scholarly journals Methylated Flavonols from Amomum koenigii J.F.Gmel. and Their Antimicrobial and Antioxidant Activities

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Minh Giang Phan ◽  
Thi Viet Huong Do ◽  
Quoc Binh Nguyen
Keyword(s):  
Escherichia Coli ◽  
Antioxidant Activities ◽  
Biological Activities ◽  
Spectroscopic Techniques ◽  
Special Group ◽  
X Ray ◽  
Rp Hplc ◽  
Dpph Scavenging ◽  
First Time ◽  
Antimicrobial Assay

Methylated flavonols form a special group with modulating biological activities in comparison with kaempferol and quercetin. The present study isolated ten compounds including two kaempferol methyl ethers: 5-hydroxy-3,7,4′-trimethoxyflavone (1), 3-hydroxy-5,7,4′-trimethoxyflavone (6); four quercetin methyl ethers: retusin (5-hydroxy-3,7,3′,4′-tetramethoxyflavone) (4), 3,5-dihydroxy-7,3′,4′-trimethoxyflavone (5), 3,4′-dihydroxy-5,7,3′-trimethoxyflavone (7), and 3,5,7,3′,4′-pentamethoxyflavone (9); β-sitosterol (2); 5-hydroxy-1-(4′-hydroxyphenyl)eicosan-3-one (3); p-hydroquinone (8); and vanillic acid (10) from the rhizomes and fruit of Amomum koenigii J.F.Gmel. (Zingiberaceae). Their structures were determined by MS, NMR, and X-ray spectroscopic techniques. Among the methylated flavonols, 1, 4–7, and 9 were isolated for the first time from the rhizomes, while 1, 4, and 5 were isolated from the fruit. Compounds 2, 3, 7, 8, and 10 were reported for the first time from the species. Three main methylated flavonols 1, 4, and 5 were quantitatively analyzed in the rhizomes of A. koenigii by RP-HPLC-DAD; their contents were determined to be 1.81% (1), 1.38% (4), and 1.76% (5). The antimicrobial assay against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Aspergillus niger, Fusarium oxysporum, Candida albicans, and Saccharomyces cerevisiae and antioxidant DPPH scavenging test were performed for the isolated methylated flavonols.

Chemical Constituents Isolated from Rhododendron ungernii with Antioxidant Profile

2019 ◽  
Vol 9 (3) ◽  
pp. 238-243 ◽  
Author(s):  
Emine Dede ◽  
Nusret Genc ◽  
Mahfuz Elmastas ◽  
Huseyin Aksit ◽  
Ramazan Erenler
Keyword(s):  
Antioxidant Activities ◽  
Biological Activities ◽  
Chemical Constituents ◽  
Reducing Power ◽  
Scavenging Activity ◽  
Isolation And Identification ◽  
Reduced Pressure ◽  
Scavenging Effect ◽  
Pharmaceutical Industries ◽  
Dpph Scavenging

Background: Plant in Rhododendron genus that contains phenolic compounds has been used in traditional medicine and revealed considerable biological activities. Objective: Isolation and identification of antioxidant natural products from Rhododendron ungernii. Methods: Rhododendron ungernii Trautv. flowers were collected and dried in shade. The dried flowers were extracted with methanol for 3 days. The solvent was removed by reduced pressure to yield the extract which was subjected to column chromatography (Sephadex LH-20, C18 reversed phase column) to isolate catechin-7-O-glucoside (1), quercetin-3-O-β-galactoside (2), quercetin-3-O- β-xyloside (3), farrerol (4), myricetin (5), and quercetin (6). The structures of isolated compounds were elucidated by spectroscopic methods such as 1D-NMR, 2D-NMR, and LC-TOF/MS. DPPH scavenging effect, ABTS+ scavenging activity, and reducing power (FRAP) were performed for antioxidant assays of isolated natural compounds. Results: Isolated flavonoids displayed the outstanding antioxidant activities. Catechin-7-O-glucoside (1) and quercetin-3-O-β-galactoside (2) (IC50, 3.66 µg/mL) had the most DPPH• scavenging effect among the compounds. The highest ABTS•+ scavenging activity (IC50, 1.41 µg/mL) and reducing power effect (6.05 mmol TE/g comp) were observed for myricetin (5). Conclusion: R. ungernii extract and isolated compounds could be a promising antioxidant for food and pharmaceutical industries.

Bleispezies PbX und PbX2 als Brückenliganden in übergangsmetallorganisch geschützten Koordinationsverbindungen/ Leadspecies PbX and PbX2 as Bridging Ligands in Organometallic Protected Coordination Compounds

2002 ◽  
Vol 57 (1) ◽  
pp. 25-42 ◽  
Author(s):  
Peter Rutsch ◽  
Gottfried Huttner
Keyword(s):  
Coordination Compounds ◽  
Dynamic Behaviour ◽  
Disodium Salt ◽  
3D Nmr ◽  
Spectroscopic Techniques ◽  
The Novel ◽  
Bridging Ligands ◽  
X Ray ◽  
Nmr Data ◽  
First Time

The disodium salt Na2[{(CO)5Cr}2Pb(NO3)2], Na2·1, which contains a lead center in a (4+2) coordination mode, reacts with tetraphenylphosphonium halides [Ph4P]X to give the tetrahedral compounds [Ph4P]2[{(CO)5Cr}2PbX2] (X = Cl: 2a; X = Br: 2b; X = I: 2c). Substitution of the nitrate groups of Na2·1 by alcoxides leads to binuclear compounds of the type [{(CO)5Crg2Pb(μ2-OR)2Pb{Cr(CO)5}2]2- (R = Et: 3a; R = n -Pr: 3b; R = i-Pr: 3c; R = Allyl: 3d). NMR experiments show that these dimeric compounds are in equilibrium with the monomeric species [{(CO)5Cr}2PbR]- .Trialkylphosphanes react with Na2·1 to give the neutral phosphane complexes [{(CO)5Cr}2Pb(PR3)2] (R=Me: 4a; R=Et: 4b; R = n-Bu: 4c), which show dynamic behaviour in solution. All of the novel compounds have been characterized by X-ray analysis, as well as by the usual analytic and spectroscopic techniques. 207Pb-NMR data of Cr(CO)5- bound lead species are reported for the first time.

scholarly journals Bio-inspired silver selenide nano-chalcogens using aqueous extract of Melilotus officinalis with biological activities

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Seyedeh Zahra Mirzaei ◽  
Hamed Esmaeil Lashgarian ◽  
Maryam Karkhane ◽  
Kiana Shahzamani ◽  
Alaa Kamil Alhameedawi ◽  
...  
Keyword(s):  
Aqueous Extract ◽  
Biomedical Applications ◽  
Size Range ◽  
Biological Activities ◽  
Spherical Shape ◽  
Silver Selenide ◽  
Melilotus Officinalis ◽  
Uv Visible ◽  
Dpph Scavenging ◽  
First Time

AbstractFor the first time, an aqueous extract of Melilotus officinalis was used to synthesize bimetallic silver selenide chalcogenide nanostructures (Ag2Se-NCs). The formation of NCs was confirmed and characterized by UV–visible and FTIR spectroscopy, SEM and TEM imaging, XRD and EDX crystallography, zeta potential (ZP) and size distribution (DLS). The bioactivities of biosynthesized Ag2Se-NCs, such as antibacterial, antibiofilm, antioxidant and cytotoxicity potentials, were then examined. Bio-based Ag2Se-NCs were successfully synthesized with mostly spherical shape in the size range of 20–40 nm. Additionally, the MIC and MBC values of Ag2Se-NCs against β-lactam-resistant Pseudomonas aeruginosa (ATCC 27853) were 3.12 and 50 µg/ml, respectively. The DPPH scavenging potential of Ag2Se-NCs in terms of IC50 was estimated to be 58.52. Green-synthesized Ag2Se-NCs have been shown to have promising benefits and could be used for biomedical applications. Although the findings indicate promising bioactivity of Ag2Se-NCs synthesized by M. officinalis extract (MO), more studies are required to clarify the comprehensive mechanistic biological activities.

scholarly journals A New 3-Prenyl-2-flavene and Other Extractives from Baphia massaiensis and Their Antimicrobial Activities

2018 ◽  
Vol 13 (4) ◽  
pp. 1934578X1801300 ◽  
Author(s):  
Ngonye Keroletswe ◽  
Runner R. T. Majinda ◽  
Ishmael B. Masesane
Keyword(s):  
Escherichia Coli ◽  
2D Nmr ◽  
Antimicrobial Activities ◽  
Spectroscopic Techniques ◽  
Good Activity ◽  
Gram Negative ◽  
E Coli ◽  
Chromatographic Techniques ◽  
Inhibition Zones ◽  
First Time

One new 3-prenyl-2-flavene, named baphiflavene A, 1, and eleven known compounds, 2-12, were isolated and reported for the first time from Baphia massaiensis using several chromatographic techniques. Their structures were elucidated using different spectroscopic techniques; 1D and 2D-NMR, HRMS, GC-MS, UV/Vis, FTIR and by comparison with literature data. The isolates were tested against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli and Candida albicans to establish their preliminary antimicrobial activities. The results revealed that compound 1 had moderate activities against both Gram positive ( B. subtilis and S. aureus) and Gram negative ( E. coli and P. aeruginosa) bacteria, and good activity against C. albicans with inhibition zones of 10–23 mm (compared to 19 mm for chloramphenicol and miconazole standards). To the best of our knowledge, this is the first phytochemical work reported on Baphia massaiensis.

scholarly journals Phenolics Contents, Xanthine Oxidoreductase Inhibitory Potential, Antibacterial and Antioxidant Activities of Cachrys libanotis L. Root Extracts

2020 ◽  
Vol 10 (4-s) ◽  
pp. 71-79
Author(s):  
Sana AOUACHRIA ◽  
Sabah Boumerfeg ◽  
Abderrahim Benslama ◽  
Naouel Boussoualim ◽  
Hayat Trabsa ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Antioxidant Activities ◽  
Biological Activities ◽  
Bovine Milk ◽  
Iron Chelation ◽  
Reducing Power ◽  
Inhibitory Effect ◽  
Chloroform Extract ◽  
Xanthine Oxidoreductase ◽  
Dpph Scavenging

To date, no studies have investigated the phytochemical screening and biological activities of Cachrys libanotis L. traditionally used for the treatment of gout and rheumatism. Therefore, we aimed to investigate, for the first time, the phytochemical contents, the xanthine oxidoreductase inhibition, antibacterial, and antioxidant activities of extracts derived from the roots of C. libanotis L. Roots were submitted to extraction and fractionation using three different solvents sequentially, in the ascending order of polarity. Subsequently, XOR was purified from bovine milk and its inhibition was evaluated using xanthine/XOR system. The antioxidant activities were assessed employed superoxide scavenging, β- carotene bleaching, DPPH scavenging, ferrous iron chelation and FRAP assays). The antibacterial activity was tested by disc diffusion assay against 11 ATCC strains. Extraction and fractionation gave crude extract (CrE), hexane extract (HxE), chloroform extract (ChE), ethyle acetate extract (EAE) and aqueous extract (AqE).  EAE exhibited the highest XOR inhibitory effect. CrE exhibited the highest effect as DPPH scavenger. All fractions exhibited a good activity against linoleate oxidation. Both CrE and AqE had an excellent chelating activity. Extracts showed a medium reducing power with greatest value exhibited by EAE. The plant extracts exhibited moderate to good antibacterial activity where the HxE extract had the strongest antimicrobial activity. From the obtained results, C. libanotis roots might be helpful in preventing or slowing the progress of gout, and it could be used as an additive in the food industry providing good protection against oxidative damage. Keywords: Cachrys libanotis, polyphenols, oxidative stress, xanthine-oxidoreductase (XOR), antimicrobial.

scholarly journals In vitro antioxidant, 𝛼-amylase and 𝛼-glucosidase activities of methanol extracts from three Momordica species

2019 ◽  
Vol 11 (1) ◽  
Author(s):  
Olubunmi Adenike Akinwunmi
Keyword(s):  
Metal Ion ◽  
Antioxidant Activities ◽  
Biological Activities ◽  
Total Phenolic ◽  
Limited Information ◽  
Glucosidase Inhibitors ◽  
Dpph Scavenging ◽  
Oral Hypoglycemic Drugs ◽  
Metal Ion Chelation

<p>Antioxidant based drug preparations are used in the prevention and management of complex diseases which include atherosclerosis, stroke, diabetes, alzheimer’s disease and cancer. Diabetes mellitus is a metabolic disorder of glucose metabolism. The management of blood glucose level is the hallmark in the treatment of this ailment, which may be achieved through the use of oral hypoglycemic drugs such as biguanides, insulin secretagogues, and 𝛼-amylase and glucosidase inhibitors. Although several biological activities had been reported for  <em>Momordica</em> <em>foetida </em>and <em>Momordica</em> <em>charantia</em>; it appears there is limited information on the  biological activity of <em>Momordica</em> <em>cissoides</em>. The purpose of this study is to compare the antioxidant, 𝛼-amylase and 𝛼-glucosidase inhibitory activities of <em>Momordica</em> <em>charantia </em>(M1), <em>Momordica</em> <em>foetida </em>(M2)<em>, </em>and <em>Momordica</em> <em>cissoides</em>  (M3) to establish a chemotaxonomic relationship between them. The antioxidant activities measured by DPPH scavenging properties, metal ion chelation, hydrogen peroxide scavenging and ABTS revealed that <em>M. foetida</em> had the highest inhibition potential, followed by <em>M. charantia</em> and the least being <em>M. cissoides</em>. In contrast, the antioxidant activities measured by FRAP,  the total phenolic content , flavonoids and tannins revealed that <em>M. cissoides</em> had the best antioxidant potential, while <em>M. foetida</em> had the least activity. The comparative α-amylase and glucosidase inhibitory studies performed demonstrated that the extracts of <em>M.cissoides </em>had the highest inhibitory potentials. Thus, the plant can be used in the management of diabetes.</p>

scholarly journals Identification of a Proanthocyanidin from Litchi Chinensis Sonn. Root with Anti-Tyrosinase and Antioxidant Activity

Biomolecules ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1347
Author(s):  
Matthew Saive ◽  
Manon Genva ◽  
Thibaut Istasse ◽  
Michel Frederich ◽  
Chloé Maes ◽  
...  
Keyword(s):  
Antioxidant Activities ◽  
Biological Activities ◽  
Chemical Characterization ◽  
2D Nmr ◽  
Ethnobotanical Study ◽  
Traditional Use ◽  
Litchi Chinensis ◽  
Isolated Compound ◽  
First Time

This work follows an ethnobotanical study that took place in the island of Mayotte (France), which pointed out the potential properties of Litchi chinensis Sonn. roots when used to enhance skin health and appearance. Through in vitro testing of a crude methanolic extract, high anti-tyrosinase (skin whitening effect) and antioxidant activities (skin soothing effect) could be measured. HPLC successive bio-guided fractionation steps allowed the purification of one of the compounds responsible for the biological activities. The isolated compound was characterized by UV, IR, MS and 2D-NMR, revealing, for the first time in Litchi chinensis Sonn. roots, an A-type proanthocyanidin and thus revealing a consensus among the traditional use shown by the ethnobotanical study, in vitro biological activities and chemical characterization.

scholarly journals Green Synthesis of Gold and Silver Nanoparticles Using Leaf Extract of Clerodendrum inerme; Characterization, Antimicrobial, and Antioxidant Activities

Biomolecules ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 835 ◽  
Author(s):  
Shakeel Ahmad Khan ◽  
Sammia Shahid ◽  
Chun-Sing Lee
Keyword(s):  
Antioxidant Activities ◽  
Biological Activities ◽  
Radical Scavenging ◽  
Ag Nps ◽  
Gold And Silver Nanoparticles ◽  
Biofilm Inhibition ◽  
E Coli ◽  
Biocompatibility Test ◽  
Pathogenic Microbes ◽  
Dpph Scavenging

Due to their versatile applications, gold (Au) and silver (Ag) nanoparticles (NPs) have been synthesized by many approaches, including green processes using plant extracts for reducing metal ions. In this work, we propose to use plant extract with active biomedical components for NPs synthesis, aiming to obtain NPs inheriting the biomedical functions of the plants. By using leaves extract of Clerodendrum inerme (C. inerme) as both a reducing agent and a capping agent, we have synthesized gold (CI-Au) and silver (CI-Ag) NPs covered with biomedically active functional groups from C. inerme. The synthesized NPs were evaluated for different biological activities such as antibacterial and antimycotic against different pathogenic microbes (B. subtilis, S. aureus, Klebsiella, and E. coli) and (A. niger, T. harzianum, and A. flavus), respectively, using agar well diffusion assays. The antimicrobial propensity of NPs further assessed by reactive oxygen species (ROS) glutathione (GSH) and FTIR analysis. Biofilm inhibition activity was also carried out using colorimetric assays. The antioxidant and cytotoxic potential of CI-Au and CI-Ag NPs was determined using DPPH free radical scavenging and MTT assay, respectively. The CI-Au and CI-Ag NPs were demonstrated to have much better antioxidant in terms of %DPPH scavenging (75.85% ± 0.67% and 78.87% ± 0.19%), respectively. They exhibited excellent antibacterial, antimycotic, biofilm inhibition and cytotoxic performance against pathogenic microbes and MCF-7 cells compared to commercial Au and Ag NPs functionalized with dodecanethiol and PVP, respectively. The biocompatibility test further corroborated that CI-Ag and CI-Au NPs are more biocompatible at the concentration level of 1–50 µM. Hence, this work opens a new environmentally-friendly path for synthesizing nanomaterials inherited with enhanced and/or additional biomedical functionalities inherited from their herbal sources.

Chemical Constituents and Biological Activities of Cirsium leucopsis, C. sipyleum, and C. eriophorum

2014 ◽  
Vol 69 (9-10) ◽  
pp. 381-390 ◽  
Author(s):  
Mehmet Boğa ◽  
Pelin Köseoğlu Yılmaz ◽  
Deniz Barıș Cebe ◽  
Mashhad Fatima ◽  
Bina S. Siddiqui ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Vanillic Acid ◽  
Antioxidant Activities ◽  
Biological Activities ◽  
Chemical Constituents ◽  
Cation Radicals ◽  
Main Fatty Acid ◽  
Butyrylcholinesterase Activity ◽  
First Time ◽  
Fatty Acid Compositions

Abstract Two endemic Cirsium species, C. leucopsis DC. and C. sipyleum O. Schwarz, and C. eriophorum (L.) Scop. growing in Turkey were investigated to establish their secondary metabolites, fatty acid compositions, and antioxidant and anticholinesterase potentials. Spectroscopic methods were used to elucidate the structures of thirteen known compounds (p-hydroxy-benzoic acid, vanillic acid, cisepoxyconiferyl alcohol, syringin, balanophonin, 1′-O-methyl-balanophonin, apigenin, kaempferol-3- O-β-D-glucopyranoside, kaempferol-3-O-α-L-rhamnopyranoside, taraxasterol, taraxasterol acetate, β-sitosterol, β-sitosterol-3-O-β-D-glucopyranoside). cis-Epoxyconiferyl alcohol and 1′-O-methylbalanophonin were isolated for the first time from Cirsium species. Palmitic acid (47:1%) was found to be the main fatty acid of C. leucopsis, linoleic acid in both C. sipyleum (42:1%) and C. eriophorum (37:8%). Assays of b-carotene bleaching, scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals, 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium (ABTS) cation radicals, and superoxide anion radicals, as well as cupric reducing antioxidant capacity (CUPRAC) were used to determine the antioxidant activities of the extracts and isolated compounds. Vanillic acid, balanophonin, and kaempferol-3-O-α-L-rhamnopyranoside exhibited strong antioxidant activity. Taraxasterol was a potent inhibitor of acetyl- and butyrylcholinesterase activity, respectively.

scholarly journals Characterization of (2E,6E)-3,7,11-Trimethyldodeca-2,6,10-Trien-1-Ol with Antioxidant and Antimicrobial Potentials from Euclea Crispa (Thunb.) Leaves

2020 ◽  
Vol 80 ◽  
pp. 51-63
Author(s):  
Chella Perumal Palanisamy ◽  
Bo Cui ◽  
Hong Xia Zhang ◽  
Thanh Trung Nguyen ◽  
Hoang Dung Tran ◽  
...  
Keyword(s):  
Biological Activities ◽  
Radical Scavenging ◽  
Reducing Power ◽  
Spectroscopic Techniques ◽  
Nitric Oxide Radical ◽  
Isolated Compound ◽  
First Time ◽  
Diffusion Assay

(2E,6E)-3,7,11-Trimethyldodeca-2,6,10-trien-1-ol or farnesol is a natural isoprenoid possessing a range of beneficial biological activities as anti-candidiasis, anti-tumor and anti-hyperglycaemia. The present study, for the first time, isolated and identified farnesol from Euclea crispa leaves’ extract, subsequently, validated its antioxidant and antimicrobial potentials. The isolated compound was confirmed by spectroscopic techniques including ultraviolet-visible (UV/Vis), fourier-transform infrared (FTIR), and 1H and 13C magnetic resonance (NMR) spectroscopies. By in vitro investigations, farnesol exhibited a considerable antioxidant activity with IC50 values of 113.79, 109.59, and 116.65 µg/mL for 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, and nitric oxide radical scavenging assays, respectively. Additionally, farnesol performed a potent reducing power capacity which was in line with ascorbic acid, an outstanding antioxidant. By the disc-diffusion assay, farnesol exposed the superior antimicrobial activity against various disease-causing microorganisms. Significantly, at the concentration of 50 µg/mL, the compound effectively inhibited the growth of Escherichia coli and Aspergillus niger with inhibition zones of 12 and 11 mm, respectively. Findings from this research suggest that E. crispa leaf is a potential source of farnesol, a powerful antioxidant and antimicrobial agent.

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