scholarly journals Antimicrobial and Antibiofilm Activities of the Fungal Metabolites Isolated from the Marine Endophytes Epicoccum nigrum M13 and Alternaria alternata 13A

Marine Drugs ◽  
2021 ◽  
Vol 19 (4) ◽  
pp. 232
Author(s):  
M. Mallique Qader ◽  
Ahmed A. Hamed ◽  
Sylvia Soldatou ◽  
Mohamed Abdelraof ◽  
Mohamed E. Elawady ◽  
...  
Keyword(s):  
Alternaria Alternata ◽  
Antibacterial Effect ◽  
Saline Lake ◽  
2D Nmr ◽  
Fungal Metabolites ◽  
Gram Positive ◽  
Gram Negative ◽  
Epicoccum Nigrum ◽  
Wadi El Natrun ◽  
New Compounds

Epicotripeptin (1), a new cyclic tripeptide along with four known cyclic dipeptides (2–5) and one acetamide derivative (6) were isolated from seagrass-associated endophytic fungus Epicoccum nigrum M13 recovered from the Red Sea. Additionally, two new compounds, cyclodidepsipeptide phragamide A (7) and trioxobutanamide derivative phragamide B (8), together with eight known compounds (9–16), were isolated from plant-derived endophyte Alternaria alternata 13A collected from a saline lake of Wadi El Natrun depression in the Sahara Desert. The structures of the isolated compounds were determined based on the 1D and 2D NMR spectroscopic data, HRESIMS data, and a comparison with the reported literature. The absolute configurations of 1 and 7 were established by advanced Marfey’s and Mosher’s ester analyses. The antimicrobial screening indicated that seven of the tested compounds exhibited considerable (MIC range of 2.5–5 µg/mL) to moderate (10–20 µg/mL) antibacterial effect against the tested Gram-positive strains and moderate to weak (10–30 µg/mL) antibacterial effect against Gram-negative strains. Most of the compounds exhibited weak or no activity against the tested Gram-negative strains. On the other hand, four of the tested compounds showed considerable antibiofilm effects against biofilm forming Gram-positive and Gram-negative strains.

scholarly journals Anti-Microbial and Remineralizing Properties of Self-Adhesive Orthodontic Resin Containing Mesoporous Bioactive Glass

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3550
Author(s):  
Aerin Choi ◽  
Kyung-Hyeon Yoo ◽  
Seog-Young Yoon ◽  
Bong-Soo Park ◽  
In-Ryoung Kim ◽  
...  
Keyword(s):  
Bond Strength ◽  
Physical Properties ◽  
Bioactive Glass ◽  
Shear Bond Strength ◽  
Antibacterial Effect ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Significant Difference ◽  
Mesoporous Bioactive Glass

Self-adhesive resins (SARs) contain adhesives, which simplify the procedures of resin application, and primers, which provide sufficient bonding ability. In this study, mesoporous bioactive glass nanoparticles (MBN) were added to a SAR to easily improve the physical properties and remineralization ability. The experimental resins comprised 1%, 3%, and 5% MBN mixed in Ortho Connect Flow (GC Corp, Tokyo, Japan). As the MBN content in the SAR increased, the microhardness increased, and a statistically significant difference was observed between the cases of 1% and 5% MBN addition. Shear bond strength increased for 1% and 3% MBN samples and decreased for 5% MBN. The addition of MBN indicated a statistically significant antibacterial effect on both gram-negative and gram-positive bacteria. The anti-demineralization experiment showed that the remineralization length increased with the MBN content of the sample. Through the above results, we found that SAR containing MBN has antibacterial and remineralization effects. Thus, by adding MBN to the SAR, we investigated the possibility of orthodontic resin development, wherein the strength is enhanced and the drawbacks of the conventional SAR addressed.

scholarly journals Microbial Transformation of Deoxyandrographolide by Alternaria Alternata AS 3.4578

2011 ◽  
Vol 6 (6) ◽  
pp. 1934578X1100600
Author(s):  
Xiu-Lan Xin ◽  
Sha Deng ◽  
Bao-Jing Zhang ◽  
Shan-shan Huang ◽  
Yan Tian ◽  
...  
Keyword(s):  
Spectral Methods ◽  
Alternaria Alternata ◽  
Microbial Transformation ◽  
2D Nmr ◽  
New Compounds

Biotransformation of deoxyandrographolide (1) by Alternaria alternata AS 3.4578 gave five derivatives identified by spectral methods including 2D NMR as the known dehydroandrographolide (2) and 9β-hydroxy-dehydroandrographolide (3) and the new compounds 9β-hydroxy-deoxyandrographolide (4), 3α,17,19-trihydroxy-8,13-ent-labdadien-15,16-olide (5) and 3-oxo-9β-hydroxy-deoxyandrographolide (6).

scholarly journals Characterization and Evaluation The Biological Activity of Prepared Nano-Gentamicin Nanoparticles

2021 ◽  
Vol 910 (1) ◽  
pp. 012078
Author(s):  
Rana A. Kamal ◽  
Quraish A. Kahdhum ◽  
Awatif I. Mohammed ◽  
Ahmed J. Essa ◽  
Maan A. Abd elhamid ◽  
...  
Keyword(s):  
Biological Activity ◽  
Antibacterial Effect ◽  
Sol Gel ◽  
Veterinary Drug ◽  
Homogeneous Distribution ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Force Microscopy ◽  
Average Size

Abstract Nanotechnology is a capable approach to enhance the activity of common antimicrobial agent mainly used in human and veterinary drug. Gentamycin is a broad-spectrum antibacterial against Gram-positive and Gram-negative bacteria. The study aims to determine the characterization and the biological activity of gentamicin in the Nano-form prepared by Sol-gel application using an ultrasound device by aqueous solution at temperature (80)0C. Nano gentamycin examined by Scanning electron microscopy (SEM), transmission (TEM), atomic force microscopy (AFM) and antibacterial effect of both Nano and stander gentamycin were analyzed. The results showed that the average size of gentamycin nanoparticles was 68.51 nanometers with homogeneous distribution. The EDX showed large number of elements present in the Nano solution. The antibacterial effect of Nano gentamycin took a wide inhibition range of Gram-positive and Gram-negative bacteria compared to the standard substance, where the inhibition diameter for E.coli was 29 mm, and for St. epidermidis was 27 mm. The MIC of gentamicin nanostructures was the concentration 0.00125 mg/ml.

scholarly journals Synthesis and Antimicrobial Evaluations of Sulfur Inserted Fluoro-Benzimidazoles

2021 ◽  
Vol 33 (7) ◽  
pp. 1525-1529
Author(s):  
Parmesh Kumar Dwivedi ◽  
Devdutt Chaturvedi
Keyword(s):  
Antimicrobial Agents ◽  
Bacterial Strains ◽  
Substituted Anilines ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
New Compounds ◽  
Derivatives Of ◽  
Multiple Step

A new series of fluorinated sulfur inserted benzimidazole analogues Za-i were synthesized and characterized. The new compounds were screened for their antimicrobial and antioxidant potential. The synthesized compounds were obtained by multiple step synthesis, initiating from the synthesis of 5-(difluoromethoxy)-1H-benzimidazole-2-thiol X. The compounds Ya-i prepared by reacting differently substituted anilines with chloroacetylchloride and triethylamine in DMF. Finally, the compound X was reacted with different derivatives of 2-chloro-N-phenylacetamide resulting in formation of titled compounds Za-i. The synthesized compounds (Za-Zi) were characterized by spectral analysis viz.1H & 13C NMR, mass spectra, elemental analysis and IR. The in vitro antimicrobial potential against Gram-positive (S. aureus and E. faecalis) and Gram-negative bacterial (E. coli and P.aeruginosa) strains as well as fungi (A. niger and C. albicans) was recorded for the obtained compounds. Some of the compounds exhibited encouraging results (in MIC) against Gram-positive and Gram-negative bacterial strains. These studies thus suggest that the designed sulfur inserted fluoro-benzimidazoles scaffold may serve as new promising template for further amplification as antimicrobial agents.

scholarly journals Synthesis and Antimicrobial Assessment of Some New 2-(Thiazol-5-yl)-1,3,4-oxadiazoles

2019 ◽  
Vol 70 (6) ◽  
pp. 1996-1999
Author(s):  
Catalin Araniciu ◽  
Smaranda Dafina Oniga ◽  
Cristina Ioana Stoica ◽  
Mariana Carmen Chifiriuc ◽  
Marcela Popa ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
1H Nmr ◽  
Elemental Analysis ◽  
Physicochemical Characterization ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
Fungal Strains ◽  
New Compounds

Considering the promising antimicrobial activity of compounds bearing the thiazole or the oxadiazole rings in their structures, we set out to obtain new antimicrobial molecules bearing the 2-(thiazol-5-yl)-1,3,4-oxadiazole schaffold. The structures of the 8 new compounds obtained was confirmed by physicochemical characterization including: 1H-NMR, MS and elemental analysis. Antimicrobial activity was investigated against 5 Gram-positive bacterial strains, 2 Gram-negative bacterial strains and 2 fungal strains. The newly synthesized compounds showed modest antimicrobial activity.

scholarly journals A Xenorhabdus budapestensis entomopatogén baktérium sejtmentes fermentlevének és tisztítottfehérje-frakciójának antimikrobiális hatása néhány zoonoticus baktériumra

2015 ◽  
Vol 156 (44) ◽  
pp. 1782-1786 ◽  
Author(s):  
Erzsébet Burgettiné Böszörményi ◽  
István Barcs ◽  
Gyula Domján ◽  
Katalin Bélafiné Bakó ◽  
András Fodor ◽  
...  
Keyword(s):  
Pasteurella Multocida ◽  
Antibacterial Effect ◽  
Conditioned Media ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Salmonella Gallinarum ◽  
Gram Positive Bacteria ◽  
Agar Diffusion Test

Introduction: Many multi-resistant patogens appear continuously resulting in a permanent need for the development of novel antibiotics. A large number of antibiotics introduced in clinical and veterinary practices are not effective. Antibacterial peptides with unusual mode of action may represent a promising option against multi-resistant pathogens. The entomopathogenic Xenorhabdus budapestensis bacteria produce several different antimicrobial peptides compounds such as bicornutin-A and fabclavin. Aim: The aim of the authors was to evaluate the in vitro antibacterial effect of Xenorhabdus budapestensis using zoonotic patogen bacteria. Method: Cell-free conditioned media and purified peptide fractions of Xenorhabdus budapestensis were tested on Gram-positive (Rhodococcus equi, Erysipelothrix rhusiopathia, Staphylococcus aureus, Streptococcus equi, Corynebacterium pseudotuberculosis, Listeria monocytagenes) and Gram-negative bacteria (Salmonella gallinarum, Salmonella derbi, Bordatella bronchoseptica, Escherichia coli, Pasteurella multocida, Aeromonas hydrophila) using agar diffusion test on blood agar plates. Results: It was found that Xenorhabdus budapestensis bacteria produced compounds with strong and dose-dependent effects on the tested organisms. Purified peptid fraction exerted a more marked effect than cell free conditioned media. Gram-positive bacteria were more sensitive to this antibacterial effect than Gram-negative bacteria. Conclusions: Antibacterial peptide compound from Xenorhabdus budapestensis exert marked antibacterial effect on zoonotic patogen bacteria and they should be further evaluated in future for their potential use in the control or prevention of zoonoses. Orv. Hetil., 2015, 156(44), 1782–1786.

Sign in / Sign up

Export Citation Format

Share Document