scholarly journals Algae Polyphenolic Compounds and Modern Antibacterial Strategies: Current Achievements and Immediate Prospects

Biomedicines ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 342 ◽  
Author(s):  
Natalya N. Besednova ◽  
Boris G. Andryukov ◽  
Tatyana S. Zaporozhets ◽  
Sergey P. Kryzhanovsky ◽  
Tatyana A. Kuznetsova ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antimicrobial Agents ◽  
Biological Activities ◽  
Antibacterial Properties ◽  
Structural Diversity ◽  
Polyphenolic Compounds ◽  
High Antimicrobial Activity ◽  
Functional Relationships ◽  
Treatment And Prevention ◽  
Polyfunctional Compounds

The increasing drug resistance of pathogenic microorganisms raises concern worldwide and necessitates the search for new natural compounds with antibacterial properties. Marine algae are considered a natural and attractive biotechnological source of novel antibiotics. The high antimicrobial activity of their polyphenolic compounds is a promising basis for designing innovative pharmaceuticals. They can become both a serious alternative to traditional antimicrobial agents and an effective supplement to antibiotic therapy. The present review summarizes the results of numerous studies on polyphenols from algae and the range of biological activities that determine their biomedical significance. The main focus is put on a group of the polyphenolic metabolites referred to as phlorotannins and, particularly, on their structural diversity and mechanisms of antimicrobial effects. Brown algae are an almost inexhaustible resource with a high biotechnological potential for obtaining these polyfunctional compounds. An opinion is expressed that the effectiveness of the antibacterial activity of phlorotannins depends on the methods of their extraction aimed at preserving the phenolic structure. The use of modern analytical tools opens up a broad range of opportunities for studying the metabolic pathways of phlorotannins and identifying their structural and functional relationships. The high antimicrobial activity of phlorotannins against both Gram-positive and Gram-negative bacteria provides a promising framework for creating novel drugs to be used in the treatment and prevention of infectious diseases.

Design, Synthesis, Evaluation of Antimicrobial Activity and Docking Studies of New Thiazole-based Chalcones

2019 ◽  
Vol 19 (5) ◽  
pp. 356-375 ◽  
Author(s):  
Christophe Tratrat ◽  
Michelyne Haroun ◽  
Iakovos Xenikakis ◽  
Konstantinos Liaras ◽  
Evangelia Tsolaki ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Antimicrobial Agents ◽  
Biological Activities ◽  
Wide Spectrum ◽  
Bacterial Species ◽  
Antibacterial Properties ◽  
Docking Studies ◽  
In Vivo Evaluation ◽  
Better Than

Background:Thiazole derivates as well as chalcones, are very important scaffold for medicinal chemistry. Literature survey revealed that they possess wide spectrum of biological activities among which are anti-inflammatory and antimicrobial.Objectives:The current studies describe the synthesis and evaluation of antimicrobial activity of twenty eight novel thiazole-based chalcones.Methods:The designed compounds were synthesized using classical methods of organic synthesis. The in vivo evaluation of antimicrobial activity was performed by microdilution method.Results:All compounds have shown antibacterial properties better than that of ampicillin and in many cases better than streptomycin. As far as the antifungal activity is concerned, all compounds possess much higher activity than reference drugs bifonazole and ketoconazole. The most sensitive bacterial species was B. cereus (MIC 6.5-28.4 µmol × 10-2/mL and MBC 14.2-105.0 µmol × 10-2/mL) while the most resistant ones were L. monocytogenes (MIC 21.4-113.6 µmol × 10-2/mL) and E. coli (MIC 10.7- 113.6 µmol × 10-2/mL) and MBC at 42.7-358.6 µmol × 10-2/mL and 21.4-247.2 µmol × 10-2/mL, respectively. All the compounds exhibited antibacterial activity against the three resistant strains, MRSA, P. aeruginosa and E.coli. with MIC and MBC in the range of 0.65-11.00 µmol/mL × 10-2 and 1.30-16.50 µmol/mL × 10-2. Docking studies were performed.Conclusion:Twenty-eight novel thiazole-based chalcones were designed, synthesized and evaluated for antimicrobial activity. The results showed that these derivatives could be lead compounds in search of new potent antimicrobial agents. Docking studies indicated that DNA gyrase, GyrB and MurA inhibition may explain the antibacterial activity.

scholarly journals Diversity Focused Semisyntheses of Tetronate Polyether Ionophores

2019 ◽  
Author(s):  
Shaoquan Lin ◽  
Han Liu ◽  
Esben B. Svenningsen ◽  
Christine Pedersen ◽  
Peter Nørby ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Cancer Cells ◽  
Mammalian Cells ◽  
Biological Activities ◽  
Structural Diversity ◽  
Bacterial Activity ◽  
Cation Binding ◽  
Detailed Understanding ◽  
Structure Activity ◽  
Aggressive Cancer

The polyether ionophores are complex natural products capable of transporting cations across biological membranes. Many family members possess highly potent antimicrobial activity and a few selected compounds have ability to target particularly aggressive cancer cells. Despite these interesting perspectives, a detailed understanding of the cellular mode-of-action of polyether ionophores is generally lacking. In principle, broad mapping of structure-activity relationships across several biological activities could provide mechanistic insights as well as identification of lead structures but access to structural diversity within the overall class is synthetically very challenging. In this manuscript, we demonstrate that novel polyether ionophores can be constructed by recycling components of highly abundant polyethers. We provide the first examples of synthetically incorporating halogen-functionalized tetronic acids as cation-binding groups into polyether ionophores and we identify analogs with strong anti-bacterial activity and minimal effects on mammalian cells.

Antioxidant and Antimicrobial Activities of the Fresh aerial parts of Ammi visnaga L. from Algeria

2016 ◽  
Vol 6 (2) ◽  
pp. 70-76
Author(s):  
Soumia Keddari ◽  
Narimen Benaoum ◽  
Yasmina Mokhtaria Boufadi ◽  
Mansouria Belhocine ◽  
Ali Riazi
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Phenolic Compounds ◽  
Biological Activities ◽  
Antibacterial Properties ◽  
Ethanolic Extract ◽  
Diffusion Method ◽  
E Coli ◽  
Ammi Visnaga ◽  
Wide Range

Medicinal plants have been used for countries as cures for human diseases because they contain components of therapeutic value. Among these medi-cinal plants, Ammi visnage which have an immense reservoir of potential compounds attributed to the secondary metabolites which have the advan-tage of being of great diversity of chemical structure and have a very wide range of biological activities. The objectives of the present work were to stu-dy the antioxidant and antimicrobial activity of phenolic compounds ex-tracted from A. visnaga L. Its extraction is performed by two methods, etha-nol extraction and water extraction. The results showed that A. visnaga L.. ethanolic extract contains a mixture of phytochemical classes as polyphenol, flavonoids and revealed that this plant has high antioxidant activity (IC50 0.069 mg/ml). Regarding the antimicrobial activity results expressed by the diameter of the inhibition zones by diffusion method AWDT, the most signifi-cant inhibition was observed against to Staphylococcus aureus (12 mm) to the ethanol extract at concentration of 100mg / ml. Thus the aqueous ex-tract had a significant inhibitory activity against on the strains Staphylococ-cus aureus (8 mm), E. coli ATCC 10536 (8 mm) to a concentration of 100 mg / ml. The results for the antibacterial properties have shown that Gram-positive bacteria (Staphylococcus aureus, Listeria monocytogenes and M. luteus.) were more sensitive than gram-negative (Pseudomonas aeruginosa, E. coli ATCC 10536) against from the action of phenolic compounds of the Ammi visnaga ethanolic extract.

scholarly journals Synthesis, Antimicrobial Activity and Molecular Docking of Novel Thiourea Derivatives Tagged with Thiadiazole, Imidazole and Triazine Moieties as Potential DNA Gyrase and Topoisomerase IV Inhibitors

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2766 ◽  
Author(s):  
Heba E. Hashem ◽  
Abd El-Galil E. Amr ◽  
Eman S. Nossier ◽  
Elsayed A. Elsayed ◽  
Eman M. Azmy
Keyword(s):  
Antimicrobial Activity ◽  
Molecular Docking ◽  
Antimicrobial Agents ◽  
Biological Activities ◽  
Topoisomerase Iv ◽  
Thiourea Derivatives ◽  
E Coli ◽  
Cytotoxicity Studies ◽  
Ic50 Values

To develop new antimicrobial agents, a series of novel thiourea derivatives incorporated with different moieties 2–13 was designed and synthesized and their biological activities were evaluated. Compounds 7a, 7b and 8 exhibited excellent antimicrobial activity against all Gram-positive and Gram-negative bacteria, and the fungal Aspergillus flavus with minimum inhibitory concentration (MIC) values ranged from 0.95 ± 0.22 to 3.25 ± 1.00 μg/mL. Furthermore, cytotoxicity studies against MCF-7 cells revealed that compounds 7a and 7b were the most potent with IC50 values of 10.17 ± 0.65 and 11.59 ± 0.59 μM, respectively. On the other hand, the tested compounds were less toxic against normal kidney epithelial cell lines (Vero cells). The in vitro enzyme inhibition assay of 8 displayed excellent inhibitory activity against Escherichia coli DNA B gyrase and moderate one against E. coli Topoisomerase IV (IC50 = 0.33 ± 1.25 and 19.72 ± 1.00 µM, respectively) in comparison with novobiocin (IC50 values 0.28 ± 1.45 and 10.65 ± 1.02 µM, respectively). Finally, the molecular docking was done to position compound 8 into the E. coli DNA B and Topoisomerase IV active pockets to explore the probable binding conformation. In summary, compound 8 may serve as a potential dual E. coli DNA B and Topoisomerase IV inhibitor.

scholarly journals DESIGN AND SYNTHESIS OF NOVEL 1-((DIMETHYLAMINO)METHYL)-3-(4-(3-(SUBSTITUTE DPHENYL)-4-OXOTHIAZOLIDIN-2-YL)PHENYLIMINO)-5-NITROINDOLIN-2-ONES AS POTENT ANTITUBERCULAR AGENTS

2019 ◽  
pp. 200-207
Author(s):  
KOSARAJU LAHARI ◽  
RAJA SUNDARARAJAN
Keyword(s):  
Antimicrobial Activity ◽  
Antimicrobial Agents ◽  
Biological Activities ◽  
Antimicrobial Activities ◽  
Mannich Bases ◽  
Proton Nuclear Magnetic Resonance ◽  
Design And Synthesis ◽  
Group Variation

Objective: Isatins have emerged as antimicrobial agents due to their broad spectrum of in vitro and in vivo antimicrobial activities. In addition, thiazolidinone also reported to possess various biological activities particularly antimicrobial activity. Due to the importance, we planned to synthesize compounds with isatin functionality coupled with thiazolidinone as possible antitubercular and antimicrobial agents which could furnish better therapeutic results. Methods: In vitro Mycobacterium tuberculosis method and agar streak dilution test are used to estimate antitubercular and antimicrobial potency of title analogs, respectively. Minimum inhibitory concentration of entire title compounds was determined against all tested microorganism such as M. tuberculosis, four Gram-positive, three Gram-negative bacteria, and two fungi. Results: A series of new thiazolidinone substituted Schiff and Mannich bases of 5-nitroisatins were designed and synthesized by a multistep synthesis from isatin. Structures of synthesized compounds are characterized using Fourier-transform infrared, proton nuclear magnetic resonance, mass spectroscopy, and bases of elemental analysis. Mild to good antitubercular and antimicrobial activity was showed by synthesized 5-nitroisatin analogs. The relationship between the biological activity and the functional group variation of the tested compounds was discussed. Conclusion: 3-(4-(3-(4-Aminophenyl)-4-oxothiazolidin-2-yl)phenylimino)-1-((dimethyl amino)methyl)-5-nitroindolin-2-one 6 and 3-(4-(3- (2-aminophenyl)-4-oxothiazolidin-2-yl)phenylimino)-1-((dimethylamino)methyl)-5-nitroindolin-2-one 13 were found to be the most potent compounds of this series which might be extended as a novel class of antimicrobial agents.

scholarly journals Synthesis and Antimicrobial Activity of Silver-Doped Hydroxyapatite Nanoparticles

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Carmen Steluta Ciobanu ◽  
Simona Liliana Iconaru ◽  
Mariana Carmen Chifiriuc ◽  
Adrian Costescu ◽  
Philippe Le Coustumer ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Pathogenic Bacteria ◽  
Antimicrobial Agents ◽  
Antibacterial Properties ◽  
Major Health Problem ◽  
Major Health ◽  
Wall Structures ◽  
Nanocrystalline Hydroxyapatite ◽  
Qualitative Assay ◽  
Antibacterial And Antifungal

The synthesis of nanosized particles of Ag-doped hydroxyapatite with antibacterial properties is of great interest for the development of new biomedical applications. The aim of this study was the evaluation ofCa10−xAgx(PO4)6(OH)2nanoparticles (Ag:HAp-NPs) for their antibacterial and antifungal activity. Resistance to antimicrobial agents by pathogenic bacteria has emerged in the recent years and became a major health problem. Here, we report a method for synthesizing Ag doped nanocrystalline hydroxyapatite. A silver-doped nanocrystalline hydroxyapatite was synthesized at 100°C in deionised water. Also, in this paper Ag:HAp-NPs are evaluated for their antimicrobial activity against Gram-positive and Gram-negative bacteria and fungal strains. The specific antimicrobial activity revealed by the qualitative assay is demonstrating that our compounds are interacting differently with the microbial targets, probably due to the differences in the microbial wall structures.

Synthesis of 2-acetylpyridine-N-substituted thiosemicarbazonates of copper(ii) with high antimicrobial activity against methicillin resistant S. aureus, K. pneumoniae 1 and C. albicans

2019 ◽  
Vol 43 (29) ◽  
pp. 11727-11742 ◽  
Author(s):  
Mani Kaushal ◽  
Tarlok S. Lobana ◽  
Lovedeep Nim ◽  
Ritu Bala ◽  
Daljit S. Arora ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antimicrobial Agents ◽  
High Antimicrobial Activity ◽  
Methicillin Resistant

The basic interest in the present study pertains to developing metal based antimicrobial agents, as several microorganisms have built resistance to the conventional drugs.

A Comprehensive Appraisal of Chalcones and Their Heterocyclic Analogs as Antimicrobial Agents

2020 ◽  
Vol 24 (23) ◽  
pp. 2755-2781
Author(s):  
Riddhi Salotra ◽  
Divya Utreja
Keyword(s):  
Antimicrobial Agents ◽  
Biological Activities ◽  
Structural Diversity ◽  
Natural Sources ◽  
Anti Cancer ◽  
Heterocyclic Derivatives ◽  
Synthetic Methodologies ◽  
Microbial Potential ◽  
High Degree ◽  
Therapeutic Profile

Owing to the growing demand for compelling antimicrobial agents, chalcones and their heterocyclic derivatives have engrossed prodigious attention of medicinal chemists as an effective clinical template for the synthesis of such agents on account of their structural diversity and molecular flexibility. Chalcones are considered as a fortunate scaffold in the field of both synthetic as well as natural product chemistry. They are reflected as a remarkable section of logically occurring pharmacophores that possess a comprehensive scale of biological activities, such as anti-cancer, anti-malarial, anti-viral and anti-inflammatory, rendering them with a high degree of assortment and noble therapeutic profile. They act as a crucial intermediate for the synthesis of novel heterocyclic skeletons holding biodynamic behavior. This review emphasizes on different aspects of chalcones including their natural sources, recent synthetic methodologies and evaluation of their anti-microbial potential. It is expected as a persuasive compilation on chalcones that may benefit the experts to design potent and less toxic chalcone referents as medicinal agents.

ACTIVITY OF PERICARP EXTRACT OF MANGOSTEEN AGAINST ORAL STREPTOCOCCI

2017 ◽  
Vol 20 (1) ◽  
pp. 41-46
Author(s):  
Dewi Nurul Mustaqimah ◽  
Josh Erry HW
Keyword(s):  
Antimicrobial Activity ◽  
Dental Caries ◽  
Streptococcus Mutans ◽  
Antimicrobial Agents ◽  
Biological Activities ◽  
World Health ◽  
Direct Result ◽  
Oral Streptococci ◽  
Oral Pathogens

The increasing prevalence of dental caries is still as a major world health problem. Caries is the direct result of acid production by cariogenic oral pathogens, especially Streptococcus mutans. New and better antimicrobial agents active against cariogenic bacteria with minimal side effects on the oral tissues are much needed, especially natural agents derived directly from plants. Phytochemical studies have shown that the extracts from various parts of mangosteen or Garciniamangostana Linn tree contain varieties of secondary metabolites such as prenylated and oxygenated xanthones, many of which have been found in vitro to have antimicrobial properties against oral pathogens. Several studies which examined the eficacy of herbal for human health have shown that xanthones from mangosteen have remarkable biological activities such as antioxidant, antimicrobial, anticancer etc, and had no cytotoxic effects on human gingival fibroblasts. Their results showed that among these xanthone derivatives obtain from pericarp extract of mangosteen, α-mangostin has the most potent antimicrobial activity against cariogenic Streptococcus mutans. It can be concluded that the strong antimicrobial activity of the pericarp extract of mangosteen is a good drug of choice that might be helpful in preventing the dental caries.

scholarly journals Preparation of Silver Nanoparticles Suitable for Textile Finishing Processes to Produce Textiles with Strong Antibacterial Properties against Different Bacteria Types

2011 ◽  
Vol 66 (9) ◽  
pp. 905-916 ◽  
Author(s):  
Boris Mahltig ◽  
Marianne Reibold ◽  
Emanuel Gutmann ◽  
Torsten Textor ◽  
Jochen Gutmann ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Antibacterial Properties ◽  
Preparation Technique ◽  
Silver Particles ◽  
High Antimicrobial Activity ◽  
Elemental Silver ◽  
Vis Spectroscopy ◽  
Potential Applications ◽  
Coating Agents

This study describes the development of a preparation technique for silver nanoparticles useable as antimicrobial material which is especially useful for textile treatment to realize antimicrobial fabrics. The silver particles need to be prepared by reduction of AgNO3 under moderate conditions and with a moderate and non-toxic reductive agent. Comparative investigations were carried out with silver particles prepared by a solvothermal process or with NaBH4 as reductive agent. Particularly, suitable silver solutions are obtained by stabilizing the silver particles with polyvinylpyrollidone PVP of high molecular weight (Mw ~ 360000 gmol−1) and the use of the non-toxic reductive agents ascorbic acid and fructose. Under these conditions the diameters of the silver particles are in the range of 10 to 30 nm as determined by HR-TEM. The formation of elemental silver has been verified by transmission electron microscopy (TEM), X-ray diffraction (XRD) and optical spectroscopy. The properties of silver particle-containing liquids were investigated by using UV/Vis spectroscopy and dynamic light scattering. Further information on particle size and size distribution was gained through SEM investigations. The prepared solutions of silver nanoparticles can be applied easily onto textiles as liquid coating agents. All prepared textile samples exhibited a high antimicrobial activity against Escherichia coli. However, only few solutions containing silver particles of smaller size exhibit high antimicrobial activity also against other types of bacteria such as Staphylococcus aureus and Streptococcus pneumoniae. Because of this high antimicrobial potential gained with silver solutions prepared in a simple process without usage of toxic components, the developed materials offer a broad range of potential applications.

Sign in / Sign up

Export Citation Format

Share Document