scholarly journals Bioactivity Study of Thiophene and Pyrazole Containing Heterocycles

2021 ◽  
Vol 37 (4) ◽  
pp. 891-899
Author(s):  
Nitin V Kale ◽  
Supriya P. Salve ◽  
Bhausaheb K. Karale ◽  
Sadhana D. Mhaske ◽  
Sushama B. Dare
Keyword(s):  
Antibacterial Activity ◽  
Inhibitory Activity ◽  
Pyrazole Derivatives ◽  
Weak Activity ◽  
Antifungal Action

Chalcones3a-fwere prepared by reacting thiophene containing pyrazolyl aldehyde (2) with different 2-hydroxy acetophenones 1a-f. The compounds3a-f were transformed into different Pyrazolines 4a-f. The formation of chromene derivatives 5a-f occurred from the cyclization of 3a-f, which were then transformed into pyrazole derivatives 6a-f. Newly synthesized compounds have promising antibacterial activity against S.typhii and S.aureus, while weak activity against B.subtilis and E.coli. Compounds 5d and 6d had significant antifungal action towardsA. niger, while most of the compounds were moderately active towards T.viride. Some of the synthesized compounds showed promising α-amylase inhibitory activity at 1 mg/mL concentration.

Microwave assisted synthesis of novel Pyrazole derivatives and their biological evaluation as anti-bacterial agents

2020 ◽  
Vol 23 ◽  
Author(s):  
Hadis Khodadad ◽  
Farhad Hatamjafari ◽  
Khalil Pourshamsian ◽  
Babak Sadeghi
Keyword(s):  
Antibacterial Activity ◽  
Aromatic Aldehydes ◽  
Catalytic Amount ◽  
Antibacterial Activities ◽  
Structural Features ◽  
Biological Evaluation ◽  
Aureus Strain ◽  
Microwave Assisted Synthesis ◽  
Pyrazole Derivatives ◽  
Microwave Assisted

Aim and Objective: Microwave-assisted condensation of acetophenone 1 and aromatic aldehydes 2 gave chalcone analogs 3, which were cyclized to pyrazole derivatives 6a-f via the reaction with hydrazine hydrate and oxalic acid in the presence of the catalytic amount of acetic acid in ethanol. Materials and Methods: The structural features of the synthesized compounds were characterized by melting point, FT-IR, 1H, 13C NMR and elemental analysis. Results: The antibacterial activities of the synthesized pyrazoles was evaluated against three gram-positive bacteria such as Enterococcus durans, Staphylococcus aureus, Bacillus subtilis and two gram-negative bacteria such as Escherichia coli and Salmonella typhimurium. Conclusion: All the synthesized pyrazoles showed relatively high antibacterial activity against S. aureus strain and none of them demonstrated antibacterial activity against E. coli.

Structure-Activity Relationship and Antimicrobial Evaluation of N-Phenylpyrazole Curcumin Derivatives

2020 ◽  
Vol 16 (4) ◽  
pp. 481-488
Author(s):  
Heli Sanghvi ◽  
Satyendra Mishra
Keyword(s):  
Antibacterial Activity ◽  
Gram Negative Bacteria ◽  
Pyrazole Derivatives ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Curcumin Derivatives ◽  
Structure Activity ◽  
Electron Donating Groups ◽  
Derivatives Of

Background: Curcumin, one of the most important pharmacologically significant natural products, has gained significant consideration among scientists for decades since its multipharmacological activities. 1, 3-Dicarbonyl moiety of curcumin was found to be accountable for the rapid degradation of curcumin molecule. The aim of present work is to replace 1, 3-dicarbonyl moiety of curcumin by pyrazole and phenylpyrazole derivatives with a view to improving its stability and to investigate the role of substitution in N-phenylpyrazole curcumin on its antibacterial activity against both Gram-positive as well as Gram-negative bacteria. Methods: Pyrazole derivatives of curcumin were prepared by heating curcumin with phenyhydrazine/ substituted phenyhydrazine derivatives in AcOH. The residue was purified by silica gel column chromatography. Structures of purified compounds were confirmed by 1H NMR and Mass spectroscopy. The synthesized compounds were evaluated for their antibacterial activity by the microdilution broth susceptibility test method against gram positive (S. aureus) and gram negative (E. coli). Results: Effects of substitution in N-phenylpyrazole curcumin derivatives against S. aureus and E. coli were studied. The most active N-(3-Nitrophenylpyrazole) curcumin (12) exhibits twenty-fold more potency against S. aureus (MIC: 10μg/mL)) and N-(2-Fluoroophenylpyrazole) curcumin (5) fivefold more potency against E. coli (MIC; 50 μg/mL) than N-phenylpyrazole curcumin (4). Whereas, a remarkable decline in anti-bacterial activity against S. aureus and E. coli was observed when electron donating groups were incorporated in N-phenylpyrazole curcumin (4). Comparative studies of synthesized compounds suggest the effects of electron withdrawing and electron donating groups on unsubstituted phenylpyrazole curcumin (4). Conclusion: The structure-activity relationship (SAR) results indicated that the electron withdrawing and electron donating at N-phenylpyrazole curcumin played key roles for their bacterial inhibitory effects. The results of the antibacterial evaluation showed that the synthesized pyrazole derivatives of curcumin displayed moderate to very high activity in S. aureus. In conclusion, the series of novel curcumin derivatives were designed, synthesized and tested for their antibacterial activities against S. aureus and E. coli. Among them, N-(3-Nitrophenylpyrazole curcumin; 12) was most active against S. aureus (Gram-positive) and N-(2-Fluoroophenylpyrazole) curcumin (5) against E. coli (Gram-negative) bacteria.

scholarly journals In vitro activities of Acacia nilotica (L.) Delile bark fractions against Oral Bacteria, Glucosyltransferase and as antioxidant

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Ali Mahmoud Muddathir ◽  
Ebtihal Abdalla M. Mohieldin ◽  
Tohru Mitsunaga
Keyword(s):  
Antioxidant Activity ◽  
Antibacterial Activity ◽  
Gallic Acid ◽  
Crude Extract ◽  
Inhibitory Activity ◽  
Oral Bacteria ◽  
Acacia Nilotica ◽  
Assay Method ◽  
Medicinal Uses ◽  
Wide Range

Abstract Background Dental caries and periodontal disease are the most common chronic infectious oral diseases in the world. Acacia nilotica was commonly known in Sudan as Garad or Sunt has a wide range of medicinal uses. In the present study, antibacterial activity of oral bacteria (Streptococcus sobrinus and Porphyromonas gingivalis), inhibitory activity against glucosyltransferase (GTF) enzyme and antioxidant activity were assayed for methanolic crude extract of A. nilotica bark and its fractions. Methods Methanoilc crude extract of A. nilotica bark was applied to a Sephadex LH-20 column and eluted with methanol, aqueous methanol, and finally aqueous acetone to obtain four fractions (Fr1- Fr4). Furthermore, the crude extract and fractions were subjected to analytical high performance liquid chromatography (HPLC). The crude extract and its fractions were assayed for antibacterial activity against S. sobrinus and P. gingivalis using a microplate dilution assay method to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), as well as GTF inhibition and antioxidant activity using ABTS radical scavenging method. Results Fractions (Fr1 and Fr2) exhibited MIC values of 0.3 mg/ml against the P. gingivalis. Additionally, Fr2 displayed MBC value of 1 mg/ml against two types of bacteria. Fr4 showed an especially potent GTF inhibitory activity with IC50 value of 3.9 μg/ml. Fr1 displayed the best antioxidant activity with IC50 value of 1.8 μg/ml. The main compound in Fr1 was identified as gallic acid, and Fr2 was mostly a mixture of gallic acid and methyl gallate. Conclusions The results obtained in this study provide some scientific rationale and justify the use of this plant for the treatment of dental diseases in traditional medicine. A. nilotica bark, besides their antibacterial potentiality and GTF inhibitory activity, it may be used as adjuvant antioxidants in mouthwashes. Further studies in the future are required to identify the rest of the active compounds.

scholarly journals Antifungal and Antibacterial Metabolites from a French Poplar Type Propolis

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Séverine Boisard ◽  
Anne-Marie Le Ray ◽  
Anne Landreau ◽  
Marie Kempf ◽  
Viviane Cassisa ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Antifungal Activity ◽  
Antimicrobial Effect ◽  
Antibacterial Activities ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Gram Positive ◽  
Weak Activity ◽  
Agar Dilution

During this study, thein vitroantifungal and antibacterial activities of different extracts (aqueous and organic) obtained from a French propolis batch were evaluated. Antifungal activity was evaluated by broth microdilution on three pathogenic strains:Candida albicans, C. glabrata, andAspergillus fumigatus. Antibacterial activity was assayed using agar dilution method on 36 Gram-negative and Gram-positive strains includingStaphylococcus aureus. Organic extracts showed a significant antifungal activity againstC. albicansandC. glabrata(MIC80between 16 and 31 µg/mL) but only a weak activity towardsA. fumigatus(MIC80= 250 µg/mL). DCM based extracts exhibited a selective Gram-positive antibacterial activity, especially againstS. aureus(SA) and several of its methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) strains (MIC10030–97 µg/mL). A new and active derivative of catechin was also identified whereas a synergistic antimicrobial effect was noticed during this study.

Aktivitas Antibakteri dari Ekstrak Etanol Ganoderma sp. Asal Pulau Lombok

2020 ◽  
Vol 6 (1) ◽  
pp. 22
Author(s):  
Adelina Oktaviani ◽  
Aida Muspiah ◽  
Faturrahman Faturrahman
Keyword(s):  
Antibacterial Activity ◽  
Inhibitory Activity ◽  
Large Diameter ◽  
Ethanolic Extract ◽  
Ethanol Extract ◽  
Positive Control ◽  
Negative Control ◽  
Gram Negative Bacteria ◽  
Activity Test

The use of antibiotics that are not according to the rules and antibiotics in the long term can cause resistance to bacteria. This study aims to determine the presence of antibacterial activity and the effect of increasing the concentration of ethanol extract of Ganoderma sp. against several test bacteria. Extract from Ganoderma sp. obtained by maceration method using ethanol 95% solvent. The extract concentrations used were 20%, 40%, 60% and 80%. This research was conducted using the wells method with ciprofloxacin as a positive control and 50% DMSO as a negative control. The parameter measured is the large diameter of the inhibition formed around the well. The results of the antibacterial activity test of ethanol extract Ganoderma sp. has greater inhibitory activity against gram-negative bacteria. The inhibitory activity of ethanolic extract of Ganoderma sp. on the growth of test bacteria increased with increasing concentration of the extract

Pegylated azelaic acid: Synthesis, tyrosinase inhibitory activity, antibacterial activity and cytotoxic studies

2021 ◽  
Vol 1224 ◽  
pp. 129234
Author(s):  
Zhijie Wang ◽  
Huijing Xiang ◽  
Pingli Dong ◽  
Tingting Zhang ◽  
Chichong Lu ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Azelaic Acid ◽  
Inhibitory Activity ◽  
Acid Synthesis ◽  
Tyrosinase Inhibitory Activity ◽  
Cytotoxic Studies

The synthesis and Angiotensin Converting Enzyme (ACE) inhibitory activity of chalcones and their pyrazole derivatives

2010 ◽  
Vol 20 (6) ◽  
pp. 1990-1993 ◽  
Author(s):  
Marco Bonesi ◽  
Monica R. Loizzo ◽  
Giancarlo A. Statti ◽  
Sylvie Michel ◽  
François Tillequin ◽  
...  
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Inhibitory Activity ◽  
Pyrazole Derivatives ◽  
Converting Enzyme ◽  
Ace Inhibitory Activity ◽  
Ace Inhibitory

Inhibition of Food-Related Pathogenic Bacteria by god-Transformed Penicillium nalgiovense Strains

1999 ◽  
Vol 62 (8) ◽  
pp. 940-943 ◽  
Author(s):  
ROLF GEISEN
Keyword(s):  
Antibacterial Activity ◽  
Inhibitory Activity ◽  
Type Strain ◽  
Salmonella Enteritidis ◽  
Pathogenic Bacteria ◽  
Wild Type Strain ◽  
Antibacterial Effect ◽  
Wild Type ◽  
Penicillium Nalgiovense ◽  
And Staphylococcus Aureus

Two strains of Penicillium nalgiovense, which carried the god gene of Aspergillus niger and had increased glucose oxidase (GOD) activity compared with the wild-type strain, were tested for their ability to suppress the growth of certain food-related pathogenic bacteria. In contrast to the wild type, which showed no antibacterial effect when grown in mixed culture with different bacteria, the two tranformed strains were highly antagonistic. The strain that expressed higher amounts of GOD in general had higher inhibitory activity. Both strains showed antibacterial activity against Listeria monocytogenes, Salmonella Enteritidis, and Staphylococcus aureus. The inhibitory activity was dependent on the glucose concentration in the medium. S. aureus was completely inhibited at 1% glucose in the presence of the higher GOD-producing transformant. In contrast, if arabinose was used as a carbon source, no inhibition occurred. If catalase was added to the medium, the inhibitory activity of the transformants was completely inactivated, indicating that the hydrogen peroxide produced was responsible for the antibacterial activity of the transformants.

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