scholarly journals Lulworthinone, a New Dimeric Naphthopyrone From a Marine Fungus in the Family Lulworthiaceae With Antibacterial Activity Against Clinical Methicillin-Resistant Staphylococcus aureus Isolates

2021 ◽  
Vol 12 ◽  
Author(s):  
Marte Jenssen ◽  
Philip Rainsford ◽  
Eric Juskewitz ◽  
Jeanette H. Andersen ◽  
Espen H. Hansen ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Fibroblast Cell ◽  
2D Nmr ◽  
Marine Fungus ◽  
Bacterial Biofilm ◽  
Structural Isomer ◽  
Resistant Bacteria ◽  
Marine Microorganisms ◽  
The Family

The emergence of drug-resistant bacteria is increasing rapidly in all parts of the world, and the need for new antibiotics is urgent. In our continuous search for new antimicrobial molecules from under-investigated Arctic marine microorganisms, a marine fungus belonging to the family Lulworthiaceae (Lulworthiales, Sordariomycetes, and Ascomycota) was studied. The fungus was isolated from driftwood, cultivated in liquid medium, and studied for its potential for producing antibacterial compounds. Through bioactivity-guided isolation, a novel sulfated biarylic naphtho-α-pyrone dimer was isolated, and its structure was elucidated by spectroscopic methods, including 1D and 2D NMR and HRMS. The compound, named lulworthinone (1), showed antibacterial activity against reference strains of Staphylococcus aureus and Streptococcus agalactiae, as well as several clinical MRSA isolates with MICs in the 1.56–6.25 μg/ml range. The compound also had antiproliferative activity against human melanoma, hepatocellular carcinoma, and non-malignant lung fibroblast cell lines, with IC50 values of 15.5, 27, and 32 μg/ml, respectively. Inhibition of bacterial biofilm formation was observed, but no eradication of established biofilm could be detected. No antifungal activity was observed against Candida albicans. During the isolation of 1, the compound was observed to convert into a structural isomer, 2, under acidic conditions. As 1 and 2 have high structural similarity, NMR data acquired for 2 were used to aid in the structure elucidation of 1. To the best of our knowledge, lulworthinone (1) represents the first new bioactive secondary metabolite isolated from the marine fungal order Lulworthiales.

scholarly journals Phenolic Compounds Diminish Antibiotic Resistance of Staphylococcus Aureus Clinical Strains

2018 ◽  
Vol 15 (10) ◽  
pp. 2321 ◽  
Author(s):  
Maria Miklasińska-Majdanik ◽  
Małgorzata Kępa ◽  
Robert Wojtyczka ◽  
Danuta Idzik ◽  
Tomasz Wąsik
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Phenolic Compounds ◽  
Mechanisms Of Action ◽  
Bacterial Biofilm ◽  
Resistant Bacteria ◽  
Promising Alternative ◽  
Low Cytotoxicity

There is a growing body of evidence that flavonoids show antibacterial activity against both Gram-positive and Gram-negative bacteria. The mechanisms of action of phenolic compounds on bacterial cell have been partially attributed to damage to the bacterial membrane, inhibition of virulence factors such as enzymes and toxins, and suppression of bacterial biofilm formation. What is more, some natural polyphenols, aside from direct antibacterial activity, exert a synergistic effect when combined with common chemotherapeutics. Many studies have proved that in synergy with antibiotics plant flavonoids pose a promising alternative for therapeutic strategies against drug resistant bacteria. In this review most recent reports on antimicrobial action of polyphenols on Staphylococcus aureus strains are described, highlighting where proven, the mechanisms of action and the structure–activity relationships. Since many reports in this field are, to some extent, conflicting, a unified in vitro and in vivo susceptibility testing algorithms should be introduced to ensure the selection of effective antibacterial polyphenolic compounds with low cytotoxicity and minimal side effects.

scholarly journals Antimicrobial Mechanism of pBD2 against Staphylococcus aureus

Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3513 ◽  
Author(s):  
Kun Zhang ◽  
Heng Zhang ◽  
Chunyu Gao ◽  
Ruibo Chen ◽  
Chunli Li
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Morphological Changes ◽  
Bacterial Species ◽  
Resistant Bacteria ◽  
Quantitative Real Time Pcr ◽  
Bacterial Membranes ◽  
Qrt Pcr ◽  
High Antibacterial Activity ◽  
Therapeutic Substance

Antimicrobial peptides (AMPs) show high antibacterial activity against pathogens, which makes them potential new therapeutics to prevent and cure diseases. Porcine beta defensin 2 (pBD2) is a newly discovered AMP and has shown antibacterial activity against different bacterial species including multi-resistant bacteria. In this study, the functional mechanism of pBD2 antibacterial activity against Staphylococcus aureus was investigated. After S. aureus cells were incubated with different concentrations of pBD2, the morphological changes in S. aureus and locations of pBD2 were detected by electron microscopy. The differentially expressed genes (DEGs) were also analyzed. The results showed that the bacterial membranes were broken, bulging, and perforated after treatment with pBD2; pBD2 was mainly located on the membranes, and some entered the cytoplasm. Furthermore, 31 DEGs were detected and confirmed by quantitative real-time PCR (qRT-PCR). The known functional DEGs were associated with transmembrane transport, transport of inheritable information, and other metabolic processes. Our data suggest that pBD2 might have multiple modes of action, and the main mechanism by which pBD2 kills S. aureus is the destruction of the membrane and interaction with DNA. The results imply that pBD2 is an effective bactericide for S. aureus, and deserves further study as a new therapeutic substance against S. aureus.

scholarly journals Ultrastructural changes in methicillin-resistant Staphylococcus aureus (MRSA) induced by metabolites of thermophilous fungi Acrophialophora levis

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258607
Author(s):  
Shivankar Agrawal ◽  
Jusna Nandeibam ◽  
Indira Sarangthem
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Ethyl Acetate ◽  
Ethyl Acetate Extract ◽  
Ultrastructural Changes ◽  
Total Phenolic ◽  
Resistant Bacteria ◽  
Significant Activity ◽  
Scanning Electron Micrographs ◽  
Methicillin Resistant

Staphylococcus aureus and Methicillin-resistant S. aureus (MRSA) remains one of the major concerns of healthcare associated and community-onset infections worldwide. The number of cases of treatment failure for infections associated with resistant bacteria is on the rise, due to the decreasing efficacy of current antibiotics. Notably, Acrophialophora levis, a thermophilous fungus species, showed antibacterial activity, namely against S. aureus and clinical MRSA strains. The ethyl acetate extract of culture filtrate was found to display significant activity against S. aureus and MRSA with a minimum inhibitory concentration (MIC) of 1 μg/mL and 4 μg/mL, respectively. Scanning electron micrographs demonstrated drastic changes in the cellular architecture of metabolite treated cells of S. aureus and an MRSA clinical isolate. Cell wall disruption, membrane lysis and probable leakage of cytoplasmic are hallmarks of the antibacterial effect of fungal metabolites against MRSA. The ethyl acetate extract also showed strong antioxidant activity using two different complementary free radicals scavenging methods, DPPH and ABTS with efficiency of 55% and 47% at 1 mg/mL, respectively. The total phenolic and flavonoid content was found to be 50 mg/GAE and 20 mg/CAE, respectively. More than ten metabolites from different classes were identified: phenolic acids, phenylpropanoids, sesquiterpenes, tannins, lignans and flavonoids. In conclusion, the significant antibacterial activity renders this fungal strain as a bioresource for natural compounds an interesting alternative against resistant bacteria.

scholarly journals Antibacterial activity of different extract of medicinal plant Antirrihnum Orontium.

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Himayat Ullah ◽  
Shehzad Saleem ◽  
Wisal Ahmad ◽  
Muhammad Hanif ◽  
Zahid Ali ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Water Extract ◽  
Flowering Plant ◽  
Diffusion Method ◽  
Water Extracts ◽  
The Family ◽  
Quaternary Base ◽  
And Staphylococcus Aureus

Antirrhinum Orontium is belonging to the family Plantaginacea commonly known as lesser snapdragon which is a flowering plant belong to genus Antirrhinum. It was traditionally used in treatment of Tumor, Eye inflammation and Ulcer. Antirrhinum Orontium is contain mostly tertiary alkaloids bases one of them is identified as 4-methyl-2, 6-naphthyridine and Choline is identified as quaternary base. The recent study is to investigate the antibacterial activity of Ethyl acetate, Dichloromethane, Hexane and Water extracts of Antirrhinum Orontium, against the pathogen like Escherichia coli and Staphylococcus aureus. Both the Soxhlet and Maceration water extract were found most active from the other extract against Escherichia coli and Staphylococcus aureus by using agar well diffusion method. The measured zone of inhibition for Soxhlet water extract is 21±0.05mm and Maceration water extract is 20±0.05mm against gram positive Staphylococcus aureus, while for gram negative Escherichia coli 23±0.05mm is measured for Soxlet and 21±0.05mm measured for Maceration water extracts

scholarly journals PROFIL KANDUNGAN KIMIA DAN AKTIVITAS ANTIBAKTERI EKSTRAK METANOL DAUN BAMBAN (Donax canniformis (G. Forst.) K. Schum.) TERHADAP Staphylococcus aureus

2015 ◽  
Vol 1 (2) ◽  
pp. 141-148
Author(s):  
Hidayatullah Hidayatullah ◽  
Syariful Anam ◽  
Muhamad Rinaldhi Tandah
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Phenolic Compounds ◽  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Methanol Extract ◽  
Minimum Bactericidal Concentration ◽  
Dilution Method ◽  
The Family

Bamban (Donax canniformis (G. Forst.) K. Schum.) is one of the family Marantaceae plant that has many uses such as traditional medicine. Methanol extract of bamban leaves contains phenolic, tannins and saponins compounds. The purpose of this research is to determine the class of compounds that has antibacterial activity against Staphylococcus aureus and determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methanol extract of bamban leaves. This extract was prepared using maceration method with methanol solvent. Determination the class of compounds was initiated by bioautografi test in order to determine spots which has have antibacterial activity. Subsequently, the spot were identified the class of compound using reagent spray FeCl3 and H2SO4 10%. The determination of MIC and MBC using dilution method. Research showed there are three compounds that had antibacterial activity. These compounds were predicted as spot I and spot II which were phenolic compounds and spot III as a saponin compound. MIC and MBC value of the methanol extract of leaves bamban leaves 8% and 13%, respectively.

scholarly journals New Iridoid from Aerial Parts of Mussaenda Roxburghii

2012 ◽  
Vol 7 (1) ◽  
pp. 1934578X1200700 ◽  
Author(s):  
Utpal Chandra De ◽  
Ranjit Ghosh ◽  
Sanjib Chowdhury ◽  
Biswanath Dinda
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
2D Nmr ◽  
Dilution Method ◽  
Chemical Methods ◽  
Aerial Parts ◽  
Broth Dilution

A new iridoid, shanzhiol (1), was isolated from the aerial parts of Mussaenda roxburghii. The structure was established by spectroscopic (including 2D NMR) and chemical methods. Shanzhiol (1) showed mild antibacterial activity against both Staphylococcus aureus and Escherichia coli with a MIC of 100 μg/mL by the broth dilution method.

scholarly journals Synthesis of Mixed Ligand Ruthenium (II/III) Complexes and Their Antibacterial Evaluation on Drug-Resistant Bacterial Organisms

2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
James T. P. Matshwele ◽  
Florence Nareetsile ◽  
Daphne Mapolelo ◽  
Pearl Matshameko ◽  
Melvin Leteane ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Magnetic Susceptibility ◽  
Klebsiella Pneumoniae ◽  
Bacterial Species ◽  
Mixed Ligand ◽  
Resistant Bacteria ◽  
Drug Resistant ◽  
Bacterial Dna ◽  
Polypyridyl Ligand

The potential antimicrobial properties of a tridentate polypyridyl ligand 4-butoxy-N,N-bis(pyridin-2-ylmethyl)aniline (BUT) 1 and its corresponding mixed ligand ruthenium complexes were investigated on drug-resistant and non-drug-resistant bacterial species. The ligand and its complexes were synthesized and successfully characterized by 1H NMR, UV/Vis, and FTIR spectra; ESI-MS; and magnetic susceptibility. Electronic spectra and magnetic susceptibility of these Ru(II)/(III) complexes suggest that they are of a low spin crystal field split, where the Ru(III) is a d5 and Ru(II) d6 low spin. These compounds were tested for antibacterial activity on two bacterial species: Staphylococcus aureus (S. aureus) and Klebsiella pneumoniae (K. pneumoniae), as well as their drug-resistant strains methicillin-resistant Staphylococcus aureus (MRSA) and multidrug resistant Klebsiella pneumoniae (MDR K. pneumoniae). All the compounds inhibited growth of the two non-drug-resistant bacteria and only one drug-resistant strain MRSA. However, only the ligands BUT and 2,2-dipyridylamine showed activity against MRSA, while all complexes did not show any antibacterial activity on MRSA. We observed large zones of inhibition for the Gram-positive S. aureus and MRSA bacteria, compared to the Gram-negative K. pneumoniae bacteria. DNA cleavage studies with gel electrophoresis showed denatured bacterial DNA on the gel from all the complexes, with the exception of the ligand, suggesting DNA nuclease activity of the complexes in the bacterial DNA.

scholarly journals A New Monoterpenoid and a New Flavonoid Glycoside from the Peels of Clausena lansium

2016 ◽  
Vol 11 (5) ◽  
pp. 1934578X1601100 ◽  
Author(s):  
Hui-Dong Deng ◽  
Cai-Hong Cai ◽  
Shuai Liu ◽  
Yan-Bo Zeng ◽  
Wen-Li Mei ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Carboxylic Acid ◽  
Inhibitory Activity ◽  
2D Nmr ◽  
Flavonoid Glycoside ◽  
Esi Ms ◽  
Inhibition Zones

One new monoterpenoid, nerol oxide-8-carboxylic acid (1), and one new flavonoid glycoside, claulansoside A (2), together with six known compounds, clausenamide (3), quercetin (4), isorhamnetin (5), dihydromyric (6), 2′',3′'-dihydroxyanisolactone (7) and ( E,E)-8-(7-hydroxy-3,7-dimethylocta-2,5-dienyloxy)psoralen (8), have been isolated from the peels of Clausena lansium (Lour.) Skeels. Their structures were determined using a combination of 1D, and 2D NMR (HMQC, HMBC, COSY and NOESY) techniques, and HR-ESI-MS analyses. Compounds 1 and 7 exhibited antibacterial activity against Staphylococcus aureus with the diameter of inhibition zones of 11.5 mm and 14.2 mm. Compounds 3 and 6 showed α-glucosidase inhibitory activity in vitro.

Synthesis Ruthenium complexes Functionalized with Benzothiophene and their Antibacterial activity against Staphylococcus aureus

2021 ◽  
Author(s):  
Xiangwen Liao ◽  
lianghong liu ◽  
yanhui Tan ◽  
guijuan jiang ◽  
haihong fang ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Mode Of Action ◽  
Antimicrobial Agents ◽  
Ruthenium Complexes ◽  
Resistant Bacteria ◽  
Drug Resistant ◽  
Drug Resistant Bacteria

New effective antimicrobial agents with novel mode of action are urgently need due to the continued emergence of drug-resistant bacteria. Here, three ruthenium complexes functionalized with benzothiophene: [Ru(phen)2(BTPIP)](ClO4)2 (Ru(II)-1), [Ru(dmp)2(BTPIP)](ClO4)2...

scholarly journals Antibacterial Activity of Different Extract of Medicinal Plant Antirrihnum Orontium.

2020 ◽  
Vol 5 (2) ◽  
pp. 51-56
Author(s):  
Himayat Ullah ◽  
Shehzad Saleem ◽  
Wisal Ahmad ◽  
Muhammad Hanif ◽  
Zahid Ali ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Water Extract ◽  
Flowering Plant ◽  
Diffusion Method ◽  
Water Extracts ◽  
The Family ◽  
Quaternary Base ◽  
And Staphylococcus Aureus

Antirrhinum Orontium is belonging to the family Plantaginacea commonly known as lesser snapdragon which is a flowering plant belong to genus Antirrhinum. It was traditionally used in treatment of Tumor, Eye inflammation and Ulcer. Antirrhinum Orontium is contain mostly tertiary alkaloids bases one of them is identified as 4-methyl-2, 6-naphthyridine and Choline is identified as quaternary base. The recent study is to investigate the antibacterial activity of Ethyl acetate, Dichloromethane, Hexane and Water extracts of Antirrhinum Orontium, against the pathogen like Escherichia coli and Staphylococcus aureus. Both the Soxhlet and Maceration water extract were found most active from the other extract against Escherichia coli and Staphylococcus aureus by using agar well diffusion method. The measured zone of inhibition for Soxhlet water extract is 21±0.05mm and Maceration water extract is 20±0.05mm against gram positive Staphylococcus aureus, while for gram negative Escherichia coli 23±0.05mm is measured for Soxlet and 21±0.05mm measured for Maceration water extracts

Sign in / Sign up

Export Citation Format

Share Document