scholarly journals Antioxidant Silver-based Biogenic Systems Generated from Arctium lappa Leaves

2020 ◽  
Vol 71 (4) ◽  
pp. 111-118
Author(s):  
Marcela Elisabeta Barbinta-Patrascu ◽  
Daniela Besliu ◽  
Aurelia Meghea

This work aims at designing through a �green� bottom-up strategy, four types of bio-based systems containing artificial cell membranes (with or without vitamin C) and silver nanoparticles (AgNPs) phyto-generated from aqueous extract of Arctium lappa leaves. The �green� approaches for AgNP synthesis, by using the vast bioreducing potential of plants are low-cost and eco-friendly procedures.Exploiting vegetal wastes as precursors for phyto-metallic nanoparticles has received attention from scientific community in the last years due to its significant economic and environmental impacts. UV-Vis absorption spectra demonstrated the biosynthesis of metallic nanoparticles which exhibited a strong SPR peak located at 437 nm wavelengths. The formation of the biocomposites containing the �green� synthesized AgNPs has been demonstrated by UV-Vis absorption spectroscopy and Dynamic Light Scattering measurements. DLS results highlighted the nanoscale size of the prepared �green� AgNPs. The physical stability of the obtained silver-based systems was evaluated through zeta potential values, based on electrophoretic mobility. The systems loaded with vitamin C proved to be more stable and showed enhanced antioxidant activities (between 72.3% to 88% evaluated by chemiluminescence technique). Our results demonstrated that these developed silver-based biogenic systems generated from Arctium lappa leaves could be used as antioxidant agents in various biomedical applications.

2021 ◽  
Vol 43 (4) ◽  
pp. 475-475
Author(s):  
Abdul Manaf Abdul Manaf ◽  
Momin Khan Momin Khan ◽  
Khair Zaman Khair Zaman ◽  
Mahboob Ali Mahboob Ali ◽  
Faima Alam Faima Alam ◽  
...  

In this research work Semicarbazide, thiosemicarbazide derivatives 3 to 25 were synthesized by conventional methods with high percentage yield and reaction rate. 1H-NMR and EIMS spectroscopic techniques were used to elucidate the structure of the synthesized compounds. The effect of thiosemicarbazide and semicarbazide derivatives as an antioxidant agents were studied by DPPH free radical scavenging, ferric ion reducing, ferrous ion chelating assays. Higher DDPH radical scavenging activity exhibited by most of the compounds as compared to standard vitamin C. Excellent ferric ion reducing activity was indicated by compounds of theseriesas compared to standard vitamin C. However most of the compounds generally showed average ferrous ion chelating activity than standard EDTA.


2019 ◽  
Vol 16 (3) ◽  
pp. 249-255
Author(s):  
Momin Khan ◽  
Umar Ali ◽  
Anis Ur Rahman ◽  
Muhammad Ibrahim ◽  
Abdul Hameed ◽  
...  

Background: The role of small molecules as antioxidants to prevent the oxidation of other molecules and inhibit them from radical formation is the area of much interest to cure disease especially cancer. Moreover, the antioxidants play important role as stabilizers to prevent oxidation of fuels and lubricants. </P><P> Methods: In the present study, fifteen tetrakis-Schiff’s bases derivatives (1-15) were synthesized and screened for their antioxidant activities. Compounds 1-15 were synthesized by continuous stirring of reaction mixture of 1,4-bis (hydrazonomethyl)benzene (1 mmol) with various substituted aromatic aldehydes (2 mmol) in distilled water using acetic acid as catalyst at room temperature for 2-10 min. </P><P> Results: Our present study showed that all compounds are better ferrous ion-chelating agents except compound 1,4-bis((E)-((E)-(3,4-dimethoxybenzylidene)hydrazono)methyl)benzene (6) (IC50 = 329.26 &#177; 4.75 &#181;M) which has slightly low activity than the standard EDTA (IC50 = 318.40 &#177; 5.53 μM). In addition, DPPH radical scavenging activity of eleven compounds showed higher activity than the standard. However, remaining four compounds showed comparable radical scavenging activity to the standard DPPH (IC50 = 257.77 &#177; 4.60 &#181;M). </P><P> Conclusion: The series of fifteen Schiff’s bases (1-15) were synthesized and evaluated as antioxidants. From both assays, it has been demonstrated that most of the tetrakis-Schiff’s bases have potential to serve as leads for the development of antioxidant agents for future research.


2020 ◽  
Vol 10 (3) ◽  
pp. 312-321
Author(s):  
Idin Sahidin ◽  
Carla W. Sabandar ◽  
Wahyuni ◽  
Rini Hamsidi ◽  
Sandra Aulia Mardikasari ◽  
...  

Background: Marine sponges provided a great source of natural products with promising biological activity. This study was aimed to investigate the chemical constituents of methanol extracts of selected Indonesian marine sponges (Callyspongia sp., Clathria sp., Melophlus sarasinorum, and Xestospongia sp.), collected from the Saponda Islands, Southeast Sulawesi, Indonesia as well as to evaluate their antimicrobial and antioxidant activities. Methods: LCMS/MS analysis used to identify the compounds. Agar well diffusion and DPPH assays were used to evaluate the antimicrobial and antioxidant activities. Results: Chemical screening reported alkaloids, terpenoids, steroids, and saponins from all investigated sponges. The LC-MS/MS analysis identified various compounds which mainly contained steroids. Antimicrobial activity (against Bacillus subtilis, Escherichia coli, Salmonella enterica, and Candida albicans) was only shown by the Xestospongia sp. extract. Meanwhile, extracts of M. sarasinorum, Xestospongia sp., and Callyspongia sp. exhibited potent radical scavenging activity. Conclusion: The study concluded that the selected sponges could provide various groups of compounds. Methanol extracts of these sponges could be used as sources of antimicrobial and antioxidant agents.


Author(s):  
Geetanjali Singh ◽  
Pramod Kumar Sharma ◽  
Rishabha Malviya

Aim/Objective: The author writes the manuscript by reviewing the literatures related to the biomedical application of metallic nanoparticles. The term metal nanoparticles are used to describe the nanosized metals with the dimension within the size range of 1-100 nm. Methods: The preparation of metallic nanoparticles and their application is an influential area for research. Among various physical and chemical methods (viz. chemical reduction, thermal decomposition, etc.) for synthesizing silver nanoparticles, biological methods have been suggested as possible eco-friendly alternatives. The synthesis of metallic nanoparticles is having many problems inclusive of solvent toxicity, the formation of hazardous byproducts and consumption of energy. So it is important to design eco-friendly benign procedures for the synthesis of metallic nanoparticles. Results: From the literature survey, we concluded that metallic nanoparticles have applications in the treatment of different diseases. Metallic nanoparticles are having a great advantage in the detection of cancer, diagnosis, and therapy. And it can also have properties such as antifungal, antibacterial, anti-inflammatory, antiviral and anti-angiogenic. Conclusion: In this review, recent upcoming advancement of biomedical application of nanotechnology and their future challenges has been discussed.


Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1230
Author(s):  
Vega Lloveras ◽  
José Vidal-Gancedo

The search for new biomedical applications of dendrimers has promoted the synthesis of new radical-based molecules. Specifically, obtaining radical dendrimers has opened the door to their use in various fields such as magnetic resonance imaging, as anti-tumor or antioxidant agents, or the possibility of developing new types of devices based on the paramagnetic properties of organic radicals. Herein, we present a mini review of radical dendrimers based on polyphosphorhydrazone, a new type of macromolecule with which, thanks to their versatility, new metal-free contrast agents are being obtained, among other possible applications.


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4587
Author(s):  
Fanny d’Orlyé ◽  
Laura Trapiella-Alfonso ◽  
Camille Lescot ◽  
Marie Pinvidic ◽  
Bich-Thuy Doan ◽  
...  

There is a challenging need for the development of new alternative nanostructures that can allow the coupling and/or encapsulation of therapeutic/diagnostic molecules while reducing their toxicity and improving their circulation and in-vivo targeting. Among the new materials using natural building blocks, peptides have attracted significant interest because of their simple structure, relative chemical and physical stability, diversity of sequences and forms, their easy functionalization with (bio)molecules and the possibility of synthesizing them in large quantities. A number of them have the ability to self-assemble into nanotubes, -spheres, -vesicles or -rods under mild conditions, which opens up new applications in biology and nanomedicine due to their intrinsic biocompatibility and biodegradability as well as their surface chemical reactivity via amino- and carboxyl groups. In order to obtain nanostructures suitable for biomedical applications, the structure, size, shape and surface chemistry of these nanoplatforms must be optimized. These properties depend directly on the nature and sequence of the amino acids that constitute them. It is therefore essential to control the order in which the amino acids are introduced during the synthesis of short peptide chains and to evaluate their in-vitro and in-vivo physico-chemical properties before testing them for biomedical applications. This review therefore focuses on the synthesis, functionalization and characterization of peptide sequences that can self-assemble to form nanostructures. The synthesis in batch or with new continuous flow and microflow techniques will be described and compared in terms of amino acids sequence, purification processes, functionalization or encapsulation of targeting ligands, imaging probes as well as therapeutic molecules. Their chemical and biological characterization will be presented to evaluate their purity, toxicity, biocompatibility and biodistribution, and some therapeutic properties in vitro and in vivo. Finally, their main applications in the biomedical field will be presented so as to highlight their importance and advantages over classical nanostructures.


Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2091
Author(s):  
Angela Spoială ◽  
Cornelia-Ioana Ilie ◽  
Denisa Ficai ◽  
Anton Ficai ◽  
Ecaterina Andronescu

During the past few years, researchers have focused their attention on developing innovative nanocomposite polymeric membranes with applications in water purification. Natural and synthetic polymers were considered, and it was proven that chitosan-based materials presented important features. This review presents an overview regarding diverse materials used in developing innovative chitosan-based nanocomposite polymeric membranes for water purification. The first part of the review presents a detailed introduction about chitosan, highlighting the fact that is a biocompatible, biodegradable, low-cost, nontoxic biopolymer, having unique structure and interesting properties, and also antibacterial and antioxidant activities, reasons for using it in water treatment applications. To use chitosan-based materials for developing nanocomposite polymeric membranes for wastewater purification applications must enhance their performance by using different materials. In the second part of the review, the performance’s features will be presented as a consequence of adding different nanoparticles, also showing the effect that those nanoparticles could bring on other polymeric membranes. Among these features, pollutant’s retention and enhancing thermo-mechanical properties will be mentioned. The focus of the third section of the review will illustrate chitosan-based nanocomposite as polymeric membranes for water purification. Over the last few years, researchers have demonstrated that adsorbent nanocomposite polymeric membranes are powerful, important, and potential instruments in separation or removal of pollutants, such as heavy metals, dyes, and other toxic compounds presented in water systems. Lastly, we conclude this review with a summary of the most important applications of chitosan-based nanocomposite polymeric membranes and their perspectives in water purification.


2012 ◽  
Vol 95 (3) ◽  
pp. 773-777 ◽  
Author(s):  
Leonardo Luiz Okumura ◽  
Luis Octávio Regasini Regasini ◽  
Daniara Cristina Fernandes ◽  
Dulce Helena Siqueira da Silva ◽  
Maria Valnice Boldrin Zanoni ◽  
...  

Abstract A fast, low-cost, convenient, and especially sensitive voltammetric screening approach for the study of the antioxidant properties of isoquercitrin and pedalitin from Pterogyne nitens is suggested in this work. These flavonoids were investigated for their redox properties using cyclic voltammetry in nonaqueous media using N,N-dimethylformamide and tetrabutylammonium tetrafluorborate as the supporting electrolyte, a glassy carbon working electrode, Ag|AgCl reference electrode, and Pt bare wire counter electrode. The comparative analysis of the activity of rutin has also been carried out. Moreover, combining HPLC with an electrochemical detector allowed qualitative and quantitative detection of micromolecules (e.g., isoquercitrin and pedalitin) that showed antioxidant activities. These results were then correlated to the inhibition of β-carotene bleaching determined by TLC autographic assay and to structural features of the flavonoids.


Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 49
Author(s):  
Hélida Gomes de Oliveira Barud ◽  
Robson Rosa da Silva ◽  
Marco Antonio Costa Borges ◽  
Guillermo Raul Castro ◽  
Sidney José Lima Ribeiro ◽  
...  

Bacterial cellulose (BC) is a natural polymer that has fascinating attributes, such as biocompatibility, low cost, and ease of processing, being considered a very interesting biomaterial due to its options for moldability and combination. Thus, BC-based compounds (for example, BC/collagen, BC/gelatin, BC/fibroin, BC/chitosan, etc.) have improved properties and/or functionality, allowing for various biomedical applications, such as artificial blood vessels and microvessels, artificial skin, and wounds dressing among others. Despite the wide applicability in biomedicine and tissue engineering, there is a lack of updated scientific reports on applications related to dentistry, since BC has great potential for this. It has been used mainly in the regeneration of periodontal tissue, surgical dressings, intraoral wounds, and also in the regeneration of pulp tissue. This review describes the properties and advantages of some BC studies focused on dental and oral applications, including the design of implants, scaffolds, and wound-dressing materials, as well as carriers for drug delivery in dentistry. Aligned to the current trends and biotechnology evolutions, BC-based nanocomposites offer a great field to be explored and other novel features can be expected in relation to oral and bone tissue repair in the near future.


2001 ◽  
Vol 675 ◽  
Author(s):  
Jeong-Seo Park ◽  
Han-Chang Kang ◽  
Kurt E. Geckeler

ABSTRACTAs [60]fullerene is a very hydrophobic macromolecule, there have been a number of attempts to make it more hydrophilic for biomedical applications. By attaching hydrophilic moieties such as poly(oxyethylene)(POE) chains and cyclodextrin molecules to [60]fullerene, novel water-soluble and biocompatible materials have been successfully prepared [1,2].The synthesis of novel macrocyclic fullerene conjugates which are water-soluble is reported. The telechelic fullerene derivatives have been prepared via addition reaction of POE-based arms with covalently bonded β-cyclodextrin (CD) to [60]fullerene. To this end, a mono-tosylated CD derivative has been prepared in pyridine and then reacted with an amino-functional POE in the presence of triethylamine. The subsequent reaction of [60]fullerene with the hydrophilic POE-conjugated CD-derivative yielded the macrofullerene after separation and purification procedures.The macrocyclic [60]fullerene derivatives obtained were soluble in water and characterized by UV-VIS and FT-IR spectroscopy as well as light scattering measurements and thermogravimetric analysis.


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